Correlative Neurosciences: Clinical Studies

PROGRESS I N BRAIN RESEARCH V O L U M E 21B C O R R E L A T I V E N E UR 0 s CI E N C E S P A R T B: C L I N I C A L S T U D I E S

PROGRESS I N BRAIN RESEARCH

ADVISORY BOARD

W. Bargmann

Shanghai

H. T. Chang E. Dc Robertis

Los Angeles

J. D. French

G oteborg

H. Hyden 3. Ariens Kappers S. A. Sarkisov

Amsterdam Moscow Amsterdam

J. P. SchadC F. 0. Schmitt

Brookline (Mass.) Tokyo

T. Tokizane

J. Z. Young

Buenos Aires Canberra

J. C. Eccles

H. Waelsch

Kiel

-t

New York London

P R O G R E S S I N BRAIN RESEARCH V O L U M E 21B

CORRELATIVE NEUROSCIENCES P A R T B:

CLINICAL STUDIES EDITED BY T. T O K I Z A N E Institute of Brain Research, University of Tokyo, Tokyo (Japan) AND

J. P. S C H A D E Netherlands Central Institute for Brain Research, Amsterdam (The Netherlands)

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List of Contributors

H. AKIMOTO,Department of Psychiatry, Faculty of Medicine, University of Tokyo, Tokyo (Japan). M. ETO, Department of Anatomy, Nippon Medical School, Tokyo (Japan). S. HIKAJ,Department of Geriatrics, Faculty of Medicine, University of Tokyo, Tokyo (Japan). S. IHIIA, School of Health Care and Nursing, University of Tokyo, Tokyo (Japan). E. INOUYE, Institute of Brain Research, Faculty of Medicine, University of Tokyo, Tokyo (Japan). T. ISHIKAWA, Department of Pharmacology, School of Medicine, Chiba University, Chiba (Japan). J. ISHJYAMA, Department of Pharmacology, School of Medicine, Chiba University, Chiba (Japan). K. IWAMA, Department of Neurophysiology, Institute for Higher Nervous Activity, Osaka University Medical School, Osaka (Japan). S. IZAWA,Department of Child Study, Japan Women’s University School of Home Economics, Tokyo (Japan). M. KADA,Institute of Brain Research, Faculty of Medicine, University of Tokyo, Tokyo (Japan). H. KAMIDE, School of Health Care and Nursing, University of Tokyo, Tokyo (Japan). S. KATSUKI, Department of Internal Medicine and Neurological Institute, Faculty of Medicine, Kyushu University, Fukuoka (Japan). S. KATSUTA, Department of Pharmacology, School of Medicine, Chiba University, Chiba (Japan). M. KAWAKAMI, Department of Physiology, Yokohama University School of Medicine, Yokohama (Japan). T. KAWAMOTO, Department of Neurophysiology, Institute for Higher Nervous Activity, Osaka University Medical School, Osaka (Japan). R. KIDO, Department of Neuropharmacology, Shionogi Research Laboratory, Shionogi & Co., Ltd., Osaka (Japan). T. KOBAYASHJ, Department of Pharmacology, School of Medicine, Chiba University Chiba (Japan). K. KUBOTA,Department of Neurophysiology, Lnstitute of Brain Research, Faculty of Medicine, University of Tokyo, Tokyo (Japan).

VI

LIST OF C O N T R I B U T O R S

Y . KUROIWA,Neurological Institute, Faculty of Medicine, Kyushu University, Fukuoka (Japan). T. MASAKI,Research Institute of Physical Culture, Nippon College of Physical Education, Tokyo (Japan). A. MATSUSHITA, Department of Neuropharmacology, Shionogi Research Laboratory, Shionogi & Co., Ltd., Osaka (Japan). M. MINAKAWA, Moro Mental Hospital, Moro, Saitama (Japan). H. MORISHITA, Rissho Women’s Junior College, Tokyo (Japan). T. MOZAI,Department of Geriatrics, Faculty of Medicine, University of Tokyo, Tokyo (Japan). H. NARABAYASHI, Department of Neurology, Juntendo Medical School, Tokyo (Japan). M. OKAMOTO, Department of Anatomy, Faculty of Medicine, Kyoto University, Kyoto (Japan). S . OKINAKA, Toranomon Hospital, Tokyo (Japan). T. OKUMA,Department of Psychiatry, Faculty of Medicine, University of Tokyo, Tokyo (Japan). Y. SADANAGA, Department of Pharmacology, School of Medicine, Chiba University, Chiba (Japan). K. SANO,Department of Neurosurgery, Faculty of Medicine, University of Tokyo, Tokyo (Japan). H. SHIKAKI, Department of Neuropathology, lnstitute of Brain Research, Faculty of Medicine, University of Tokyo, Tokyo (Japan). T. TAKUMA, Department of Psychology, Gakushuin University, Tokyo (Japan). T. TOKIZANE, Department of Neurophysiology, Institute of Brain Research, Faculty of Medicine, University of Tokyo, Tokyo (Japan). K . UEKI,Department of Neurosurgery, Brain Research Institute, Niigata University School of Medicine, Niigata (Japan). M. UMEGAKI, lnstitute of Brain Research, Faculty of Medicine, University of Tokyo, Tokyo (Japan). H. UTENA,Department of Neuropsychiatry, Gunma University School of Medicine, Maebashi (Japan). K. YAMAMOTO, Departnient of Neuropharmacology, Shionogi Research Laboratory, Shionogi & Co., Ltd., Osaka (Japan). N. YANAGISAWA,Department of Neuropathology, lnstitute of Brain Research, Faculty of Medicine, University of Tokyo, Tokyo (Japan). M. YOSHIKAWA, Department of Geriatrics, Faculty of Medicine, University of Tokyo, Tokyo (Japan).

VII

Other volumes in this series:

Volume 1 : Brain Mechanisms Specific and Unspecific Mechanisms of Sensory Motor Integration Edited by G. Moruzzi, A. Fessard and H. H. Jasper

Volume 2: Nerve, Brain and Memory Models Edited by Norbert Wiener? and J. P. Schade

Volume 3 : The Rhinencephalon and Related Structures Edited by W. Bargmann and J. P. Schade

Volume 4 : Growth and Maturation of the Brain Edited by D. P. Purpura and J. P. Schade

Volume 5 : Lectures on the Diencephalon Edited by W. Bargmann and J. P. Schade

Volume 6 : Topics in Basic Neurology Edited by W . Bargmann and J. P. Schad6

Volume 7 : Slow Electrical Processes in the Brain by N . A. Aladjalova

Volume 8 : Riogenic Amines Edited by Harold E. Himwich and Williamina A. Himwich

Volume 9: The Developing Brain Edited by Williamina A. Himwich and Harold E. Himwich

Volume 10: The Structure and Function of the Epiphysis Cerebri Edited by J . Ariens Kappers and J. P. Schade

Volume 11 : Organization of the Spinal Cord Edited hy J . C. Eccles and J. P. Schade

Volume 12: PhysioloRy of Spinal Neurons Edited by J . C. Eccles and J. P. Schad6

Volume I3 : Mechanisms of Neural Regeneration Edited by M . Singer and J. P. Schadh

Vlll

Volume 14: Degeneration Patterns in the Nervous System Edited by M. Singer and J. P. Schade

Volume 15 : Biology of Neuroglia Edited by E. D. P. De Robertis and R. Carrea

Volume 1 6: Horizons in Neuropsychopharriiacology Edited by Williamina A. Himwich and J. P. Schadt

Volume 17: Cybernetics of the Nervorrs System Edited by Norbert Wiener? and J. P. SchadC

Volume 18: Sleep Mechanisms Edited by K. Akert, Ch. Bally and J. P. Schadt

Volume 19: Experimental Epilepsy by A. Kreindler

Volume 20 : Pharmacology and Physiology of the Reticular Forriiafion Edited by A. V. Valdman

Volume 21 A : Correlative Neurosciences Part A : Fundamental Mechanisms Edited by T. Tokizane and J. P. Schade

Volume 22: Brain Reflexes Edited by E. A. Asratyan

Volume 23: Sensory Mechanisms Edited by Y . Zotterman Volume 24: Carbon Monoxide Poisoning Edited by H. Bour and I. McA. Ledingham Volume 25: The Cerebellum Edited by C . A. Fox and R. S. Snider

Volume 26: Developmentul Neurology Edited by C. G. Bernhard

Volume 21: Structure and Function of the Limbic System Edited by W. Ross Adey and T. Tokizane

IX

Preface

Medical and biological sciences in Japan have a long history. As far back as 562 A D medical books were introduced from China, initiating a long period of fruitful medical education and practice. An important era of scientific interest in the structure and function of the nervous system began in 1911 with the publication by Prof. Shiro Tashiro on the carbon dioxide production of nerve fibers. Prof. Genichi Kato announced in 1920 his famous theory of non-decremental nerve conduction and presented all the evidence at the International Physiological Conference in 1926. His iesearch was a major breakthrough in the physiology of single nerve fibers. He had a profound influence on the development of physiology in Japan and directing interest toward neurophysiology. From that time on the majority of Japanese scientists have been engaged in research in the brain sciences. The present volume is the second of a set of two, containing reviews and surveys of brain research in the major Japanese institutes and neurological clinics. It particularly reflects the progress of Japanese research in the clinical neurological sciences. A wide range of topics has been discussed such as: the action of psychotropic drugs, clinicopathological studies on cerebral vascular diseases, clinical studies on sleep mechanisms afid basic and clinical neurosurgical techniques and research. It is a rare occasion that one acquires an overall view of the research activities of a large country in such an important field of the medical sciences. We trust this volume will provide a means of evaluating the level of brain research in Japan. The Editors

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XI

Contents

List of contributors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . V Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . IX Effect of bovine brain hydrate on mentally retarded children: A multidisciplinary clinical experiment using co-twin control E. Inouye, H. Kamide, S. Ihda, S. Tzawa, T. Takuma, T. Masaki, H. Morishita, M. Eto, 1 M. Umegaki and M. Kada (Tokyo, Japan) . . . . . . . . . . . . . . . . . . . . . . Hippocampal after-discharge and the mode of action of psychotropic drugs T. Ishikawa, Y. Sadanaga, S. Katsuta, J. Ishiyama and T. Kobayashi (Chiba, Japan) . . . . 40 Responsiveness of cat motor cortex to electrical stimulation in sleep and wakefulness K. Iwama and T. Kawamoto (Osaka, Japan) . . . . . . . . . . . . . . . . . . . . . 54 Epidemiological and clinicopathological study on cerebrovascular disease in Japan S. Katsuki (Fukuoka, Japan) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 Facilitatory and inhibitory effects of hypothalamic-hypophyseal activity upon spontaneous paradoxical sleep (EEG after-reaction) M. Kawakami (Yokohama, Japan) . . . . . . . . . . . . . . . . . . . . . . . . . 90 Behavioural and electrophysiological study of drugs affecting brain and motor system in animal experiments R. Kido, K. Yamamoto and A. Matsushita (Osaka, Japan) . . . . . . . . . . . . . . . 113 Studies on the human triangular tract of Helweg M. Okamoto (Kyoto, Japan) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150 Multiple sclerosis and allied diseases in Japan : Epidemiological and clinical aspects S . Okinaka and Y. Kuroiwa (Tokyo and Fukuoka, Japan) . . . . . . . . . . . . . . . 183 Behavioral aberrations in methamphetamine-intoxicated animals and chemical correlates in the brain H. Utena (Maebashi, Japan) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192 Fundamental and clinical studies on the neural mechanism of sleep T. Okuma and H. Akimoto (Tokyo, Japan) . . . . . . . . . . . . . . . . . . . . . 208 Studies on the paradoxical phase of sleep in the cat T. Tokizane (Tokyo, Japan) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230 Clinical and epidemiological studies on hepatocerebral disease in Japan M. Yoshikawa, T. Mozai and S. Hirai (Tokyo, Japan). . . . . . . . . . . . . . . . . . 269 Hemispherectomy in the human with special reference to the preservation of function K. Ueki (Niigata, Japan). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285 Reconsideration of ventrolateral thalamotomy for hyperkinesis H. Narabayashi and K. Kubota (Tokyo, Japan) . . . . . . . . . . . . . . . . . . . . 339 Sedative stereoencephalotomy : Fornicotomy, upper mesencephalic reticulotomy and posteromedial hypothalamotomy 350 K. Sano (Tokyo, Japan) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Clinico-pathological and histochemical studies of Hallervorden-Spatz disease with torsion dystonia with special reference to diagnostic criteria of the disease from the clinico-pathological viewpoint N. Yanagisawa, H. Shiraki, M. Minakawa and H. Narabayashi (Tokyo, Japan). . . . . . . 373 426 Author Index. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 432 Subject Index. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Effect of Bovine Brain Hydrate on Mentally Retarded Children : A Multidisciplinary Clinical Experiment Using Co-Twin Control E I J I INOUYE’, H I R O Y U K I KAMIDE’, S H I N I H D A S , S H U J I IZAWA3, T A K E T O S H I TAKUMA4, T A K E 0 MASAKI5, H A R U M I MORISHITA6, M O R I H A R U ~ ~ 0 M7 A. R I U M E G A K T I A N D M I C H I K O K A D A ~ Institute of Brain Research, University of Tokyo School of Medicine’; School of Health Care and Nursing, University of Tokyo2; Department of Child Study, Japan Women’s University School of Home Economics3; Department of Psychology, Gakushuin University4; Research Institute of Physical Culture, Nippon College of Physical Education5; Rissho Women’s Junior College6; Department of Anatomy, Nippon Medical School7

INTRODUCTION

The biological effect of the administration of brain and spinal cord tissues has been extensively investigated since the pioneer work of Choroschko (1912), and these studies have contributed considerably to the progress of research on demyelinating diseases. On the other hand, extracts of these tissues or related amino acids were also used in clinical experiments on improvement of mental functioning or on the treatment of diseases and functional disorders of the central nervous system, since Price el al. (1943) gave DL-glutamic acid hydrochloride to patients with petit ma1 and psychomotor seizures. Readers may refer to Zimmerman et al. (1946), Mayer-Gross and Walker (1947), Hetzel (1954), Harrer (1954) and Wada et al. (1961). The present experiment used a carefully selected methodology which was considered to be important in evaluating the functioning of the central nervous system and behavior in man. The subjects were 6 pairs of monozygotic twins; one twin of a pair was given Ceremon*, while the other twin was given a placebo, by the double blind method. After one year’s administration all twins were given the placebo for an additional year. During 2 years of experiment various tests were periodically repeated, and the result of each test was independently evaluated by a member of the research team consisting of the present authors. The integration of the findings was made by the senior author after searching discussions held among the research team members.

* Each tablet of Ceremon contained 125 mg bovine brain hydrate, 20 mg chondroitin sulphate, 20 nig L-glutaniic acid, and vitamins BI, Bz, Bfi and C. The bovine brain hydrate, prepared from fresh bovine brains hydrolyzed by activated pancreas homogenate, contained 51 % of amino acids and 49% of lipids. More detailed information on this substance may be obtained from Kaken Yakukako K. K., 3-1, Nihonbashi Honcho, Cyuo-ku, Tokyo, Japan. References p. 39

2

E. I N O U Y E

et al.

SUBJECTS

In 1958 a registration of I948 pairs of twins was filed at the Institute of Brain Research of the University of Tokyo. The twins were children attending public primary schools in the Tokyo Metropolitan area with a total number of pupils around 640,000. Samesexed twins reported to be similar-looking and to be below a certain level of intelligence were selected. The level of intelligence was 1Q 60 or standard deviation 30 in one twin and IQ 70 or standard deviation 35 in the other. Twenty-five pairs fell within these limits, and they were invited to receive a drug, possibly effective in improving their behavior. At first 13 pairs responded, but during 2 years of experiment five pairs discontinued. Complete records of 8 pairs of twins were thus obtained. Zygosity diagnosis of the 8 same-sexed twin pairs was made by the method of lnouye (1962), which entails testing of ABO blood group, MN type, salivary excretion type, ear wax type, presence or absence of mid-digital-hair, taste ability to phenylthiocarbamide and finger-prints. The results showed that 6 pairs were monozygotic (MZ) with the probability being MZ over 0.968, and 2 pairs were dizygotic (DZ) with the probabilities 0.854 and 0.100. The two DZ pairs were discarded. In the remaining 6 MZ pairs the numbers of both sexes were the same, and the ages were between 8 years 10 months and 12 years 1 month at the beginning of the experiment. Before administration of the drug was started, detailed inquiries into family and personal histories as well as interviews of available family members were made. Records of school achievements and physical examinations at schools were also checked. Medical, neurological and psychiatric examinations were made at this time. First periodical tests were conducted before starting the administration of drug or placebo. Summaries of information, test results and the diagnoses of the subjects are shown in Tables 1 and 11. Since the subjects were selected from among the children attending school classes for average children, severe mental deficiency is not included. As seen in Tables I and 11, the diagnostic category o f 2 members was the same in every pair. There were 3 pairs with total personality retardation, 2 pairs with subcultural mental deficiency and one pair of subclinical epilepsy. The subjects of this experiment are thus to be called mentally retarded children. METHODS

The experiment started in December 1960, and finished in January 1963. As to the method of administering the drug, one twin in every pair was given 12 tablets of the drug orally per day, and the other twin was given the same number of placebo tablets, for one year by the double blind method”. In the following chapters the 6 MZ twin subjects receiving the drug will be called ‘C’,and the 6 control MZ twin subjects ‘P’. The actual intake doses of the drug were between 7 and 12 tablets per day. After 3

* Pairs of the drug and placebo were prepared by the first investigator in random order. The drug and placebo were given to a pair of twins by the second investigator, so the twin subjects rcceiving the drug were randomly chosen.

BOVINE BRAIN HYDRATE IN MENTAL RETARDATION

3

months of administration the senior author knew which were C subjects for the purpose of reporting the preliminary results (Inouye, 1963). He then withdrew from contacting the subjects. After one year of the administration of drug or placebo all research members were told which were C subjects. The next year was the control period, in which all C and P subjects were given placebo. During the two years’ course of the experiment various tests were performed periodically (Table 111). In the following chapters the time of the periodical tests will be called ‘0 month’, ‘3 months’ and so on, corresponding to Table 111. Detailed methods of the tests will appear in the chapter of results. All measurements and indices of the test results were statistically examined in 3 ways. The first was the test of difference of average vectors* between C and P groups by the F-test, for the purpose of testing a difference between 2 groups of the sequences of test results extending over 3 times of examination. The second was the test of a difference between 2 groups of the gains of test results on two occasions of examination by t-test. The third was the comparison of the gain in a C subject to the rejection limits of the gains in the P group. RESULTS

A survey of the results of clinical observations on behavioral and physical changes is shown in Tables IV and V, together with the summaries of information given by families. The results will be reviewed later. Pathological findings in blood and urine tests are also shown in Tables IV and V. Slight anemia was seen in 2 C and 2 P subjects, and urine protein was seen in 2 P subjects during the course of the experiments. Results of statistical tests on erythrocyte count, hemoglobin content, hemoglobin index and leucocyte count are shown in Tables VI and VII. Among the results in Table V1 changes of hemoglobin index during 0-12 months were significantly different between the C and P groups. In this period the average change in the C group was -4.16, and it was +15.83 in the P group, indicating a decrease in hemoglobin index in the C group. The results shown in Table VII will be reviewed later. Observation on the ossification in carpal bones was made on roentgenograms, compared with the atlas of Greulich and Pyle (1959). This atlas is a standard, but Eto, one of the authors, examined the ossification in scaphoid bones, trapezium bones, trapezoid bones, distal end of ulna, pisiform bones and sesamoid bones in the tendon of the adductor pollicis in Japanese children, and found the appearance of the epiphysis ossification center in pisiform and sesamoid bones was delayed as compared with the standard. The result before the administration of the drug is shown in Table V111: the bone age in all C and P subjects had not been delayed, and there was no intra-pair difference of the bone age at 0 month. The development of the bone age during the 2 years’ course was also not delayed in all subjects, and there was no intrapair difference of the development between the C and P subjects of a pair.

*

Statistical Tables I, ed. Tokei Kagaku Kenkyukai (1943) (pp. 133 and 158).

Rrfrrenres p . 39

P

TABLE I SURVEY OF THE SUBJECTS ( M A L E )

Case

Y.N.(C)* K.N.(P)** Born Feb. 10, I949 (1)

S.K . I C )

A. Y .(C) M. Y.(P) Born March 4 , 1950 (3)

K .K . ( P ) Born March 13, I951 12)

Family history

First cousin marriage of parents Father: epileptic personality, IQ 75 Paternal uncle: general paresis?

Father: heavy drinker, IQ 69 Mother: mentally retarded, stand. devn. 11 Maternal uncle: mental deficiency?

Father: heavy drinker, tends to pathological intoxication Mother: below moron, stand. devn. 5

Past history

P: first born, birth weight 3000 g C : born 5 min later, birth weight 3000 g C,P: delayed speech development C,P: age 3 measles; age 4 pertussis; age 5 appendicitis C: age 5 left otitis media; age 6 appendectomy

Severe edema and hyperemesis of mother Premature birth (32-36 weeks) P: first born, birth weight 1425 g, weak at birth, retentio testis C: birth weight 1500 g P: age 2 a convulsion C,P: age 6 mumps and measles C : since age 7 otitis media chr. C, P: neglected by parents

C: first born, birth weight 2250 g P: born 5 min later, birth weight 2250 g C,P: age 1 pertussis; age 6 measles C: cyanosis after crying twice P: age 4 polio? recovered after 1 week

I lbits

C,P: somnambulisnl once a week, decreased in frequency

C,P: nycturia; squeamish on foo

C,P: nycturia

School achievement*** C,P: mostly 1 or 2 , few 3 (Pis better)

C,P: mostly 1, few 2

C,P: mostly 1, few 2

Present status (a) Physicaldevelopment5 C,P: well developed in body weight, chest girth, biacromial breadth, max. head breadth and biacromial breadthjstature Difference between C and P : 0.74

C,P: delayed in chest girth, chest girthhtature and max. head length C,P: ratios of trunk length and upper limb length to stature are great C : delayed in body weight

C,P: delayed in max. head length; well developed in biacromial breadth/ stature P: well developed in biacromial breadth C: ratio of upper limb length/stature

P. d ~ l a v ~ rinl

may

head hrrnrlth

i c vrpnt

I, F _I

3

2

P

(c) Neurological and psychiatric symptoms C,P: spike-waves under photic stimulation C,P: reticent, slow in action

(d) IQ@

c:91-97 P: 9 4 1 0 7

Diagnosis

C,P: subclinical epilepsy, epileptic personality, normal or borderline intelligence

* **

C,P: irregular EEG C: exotropia; dysarthria P: paresis of right cranial nerves IX and XII? C,P: hyperactive, distracted attention, hypersensitive, increased suggestibility, lack of inhibition

C,P: irregular EEG C,P: hyperactive, distracted attention C : slow in action, depressed-irritable

C: 82-111 P: 66-113

C: 61-75 P: 60-74

C,P: exogenous total personality retardation, borderline intelligence

C,P: subcultural mental deficiency, moron

The twin receiving the drug. The twin receiving placebo. *** Grades of school achievements: grade 1 designates the poorest achievement. 5 Each anthropometric item in each subject was compared with the standard reported by Tofukuji (1957). Items showing greater relative deviations than 1.O in head measurements and than 2.0 in other measurements and indices are indicated. The difference between C and P is average percentage deviation of 20 anthropometric items. 19 Maximum and minimum of 3 kinds of intelligence tests: Suzuki-Binet, WISC and Shin-Tanaka B. The last test was performed after the administration of the drug.

+

+

T A B L E I1 SURVEY OF THE SUBJECTS (FEMALE)

Case

Family history

Y.M.( C ) E.M . ( P ) Born Dec. 20,1950 (4)

Mother: sickly Maternal uncle: mental deficiency?

T.F. (C) S.F. (P) Born Jan. I , 1950 (5)

K . Y.(C) H . Y.(P) Born Jan. 24, 1952 (6)

Father : heavy drinker Maternal grandmother: below imbecility

rn 3

z

0 C

< Pregnancy toxemia of mother; early rupture of membrane, severe bleeding at delivery C : first born, birth weight 2325 g P : born 10 min later, birth weight 1800 g C,P: asphyxia neonatorum, icterus gravis neonatorum C,P: delayed walk and speech development C,P: age 4 pertussis; age 6 measles P: age 2 m. pneumonia; age 5 nephritis; age 8 otitis externa

P: first born, birth weight 1575 g Severe edema of mother C: born 10 min later, birth weight Premature birth at 8 months 1540 g, weak at birth C: first born, birth weight 1425 g, C,P: slightly delayed speech development right luxatio coxae cong. C,P: age 3 measles P: born 5-10 min later, birth weight 1500 g C,P: delayed walk and speech development P: age 3 malnutrition C,P: age 7 measles C: age 9 operation of luxatio coxae cong.

Habits

C,P: nycturia, car sickness

C: squeamish on food

C,P: squeamish on food

School achievement

C,P: mostly 2 or 3

C,P: mostly 1 or 2

C,P: all 1 or 2

Past history

m

b a

I

Present status (a) Physical development C,P: delayed in max. head length C: well developed in max. head breadth Difference between C and P: 1.45 (C was better)

C,P: delayed in max. head length C: well developed in upper limb length, upper limb length/stature and upper limb length/lower limb length P: delayed in max. head breadth and chest girth/stature Difference between C and P: 1.94 (P was better)

C,P: delayed in lower limb length, max. head breadth and lower limb length/ stature C,P: ratio of trunk lengthlstature was great C: delayed in max. head length P: delayed in stature Difference between C and P: 0.88

C: shortened left leg, limping; slight anemia

C,P: clinodactyly of little fingers of both sides P: positive urine protein and urobilinogen

C,P: normal EEG C,P: reticent, slightly poor understanding C : slightly more active than P P: insensible. lack of volition

C,P: normal EEG (P: irregular slow waves) C,P: reticent, shy, sensitive, immature, good understanding

m PJ 3.

(b) Physical symptoms C,P: myopia C: slight anemia (c) Neurological and psychiatric symptoms C,P: unstable autonomic functions C,P: parietal dominant slow EEG C,P: inactive, insensible, immature, dependent, good understanding

3

m

z

( 4 IQ

C : 95-1 24 P: 106-125

C: 70-98 P: 66-85

C: 60-74 P: 61-75

Diagnosis

C,P: exogenous total personality retardation, normal intelligence

C,P: subcultural mental deficiency, upper limit of moron

C,P: exogenous total personality retardation, borderline intelligence or upper limit of moron

0

z

TABLE I11 T E S T I T E M S A N D T H E T I M E O F TESTS ( M O N T H S )

0 Before adininistration

Test items

Clinical observation Blood and urine tests Observation on ossification in carpal bones EEG Anthropometry Motor ability test Intelligence tests Social adaptability test

+

+

3

3

+

6

9

6 9 after administration started

+ +

T

12

I5

I2

3

-

18

24

6 9 after adniinistration ceased

+

A

+

+

+

-

21

12

+ +

+

t

?

c

+ + +

i

+

H

z

+

0

C 4

m

TABLE IV C O U R S E O F B E H A V I O R A L A N D P H Y S I C A L C H A N G E (MALE)*

Case

IC

3 months Dominates P (no change; better appetite than P)

IP

(No change)

2 c

2P

(Good appetite; (Good appetite) sometimes otorrhea)

3c (Sometimes gets angry; stealing)

3P (Calmed down)

6 months (No change; entered (More active than C ; (Good appetite; junior high school) entered junior high grew stronger; school) became a little active in studies)

9 months (No change)

More active than C

Marked physical development (normal appetite; grew stronger)

Slightly depressedirritable (calmed down)

(Normal appetite; (No change in school (Improved in school improved in school achievement) achievement more achievement) than P)

Attention easily distracted; slight anemia (calmed down) (Improved in school achievement)

12 months More reticent, less sensible than P (no change in school achievement)

More sensitive, more (Became active in active than C studies; improved (improved a little in school in school achievement) achievement)

Less active than C (not active in studies)

Became more active than before (improved a little in school achievement)

More active than C (improved a little in school achievement)

15 months More reticent, less sensible than P (no change)

More sensitive, active, beloved by mother than C (no change)

(No change)

(No change)

More active than C (no change)

A little hypochon-

More active than P; (Entered junior high slight anemia school; no change; (entered junior high better school school; no change; achievement than C ) sometimes becomes angry)

More talkative, restless than P (had food intoxication)

A little hypochonMore free in 18 months A little hypersensitive; frustrated behavior; less driac; dominates (irritable, quarrelfrustrated (improved over P some) a little in school achievement; active in club activities)

driac; more restless, insensible than C; attention easily distracted

W

0

sz m W

%

st

5

rn

z 1 >

tP n 1

21 months (A little improved in (No change in school achieveschool achievement; right otitis ment) media) 24 months (No change)

(No change)

Reticent; insensible, (No change) became similar to C

Information in parentheses was obtained from families.

(No change)

More active than P (a little improved in school achievement)

( N o change)

More stable feelings than C (no change)

More active than P (No change)

(No change)

TABLE V C O U R S E O F B E H A V I O R A L A N D P H Y S I C A L C H A N G E (FEMALE)

Case

4 c

4P

5 c

5P

(Became a little More insensible active in studies ; than C squeamish on food) (became a little active in studies; better appetite than C)

6C

(Better appetite than P)

6P

3 months Good stature development (caught cold, had fever; good appetite; gained color)

Tends to be dependent (gained color)

(Unstable appetite)

6 months Smiling, more active than P (no change)

More inactive, (Became possible depressed-irritable to study) than C; positive urine protein (no change)

(Good appetite)

(Became a little fat; (Same as C) no change in vol tion t o studies)

9 months (Better appetite than P)

More depressed(No change) irritable, shyer than C (no change, mure open-minded than C)

(No change)

More active than P

(Grew taller)

12 months More conscious of being dominant (good appetite; helps well in housework)

Follows C; slight anemia (interested in studies)

More organized (Improved a little in response behavior in school than P; slight achievement; a anemia (improved little irritable) in school achievement)

More active, matured (Grew stronger; bethan P came a little fat; im(became a little fat; proved in gymimproved in nastics achievement) Japanese achievement)

15 months Gained better color than P mlpa well in

(No change)

More active than P (no change)

(No change)

More insensible than C 6xwiYaihlaodirrg)

(No change)

s2 wP %

18 months More active, mature than P

(More active than C; active in studies)

(Entered junior (Entered junior More inactive than P Became more active than before; positive high school; less high school; gingival (improved a little in school achieveurine protein appetite; helps bleeding; more ment) (improved a little in well in housework) stubborn, idler than C) school achievement)

21 months (No change)

(Appendectomy ; improved a little in school achievement)

More active than P; dominates P (improved a little in school achievement)

(No change)

24 months (No change)

(No change)

(Good school achievement)

More stubborn, More inhibited more exaggerated than P (no change) ego-feelings than C

P

2

(Otitis externa)

(Became a little fat; otitis externa)

W

Positive urine protein (no change)

0

2 2

T A B L E VI STATISTICAL EVALUATION OF HEMATOLOGICAL E X A M I N A T I O N S : DIFFERENCE BETWEEN

c AND

P

GROUPS

2

F-values

Period in months: 0 4 - 1 2

6-12-18

m

t-values

12-18-24

0-12-24

0 4

6-12

0-12

12-18

12-24

0-24

~

1. Erythrocyte count

1.416

0.711

0.023

0.402

0.758

0.070

0.986

0.704

0.944

0.178

2. Hb content

0.389

0.388

1.183

0.474

0.239

-

0.083

-

0.364

-

3. Hb index

2.210

1.563

0.417

1.124

0.869

0.998

2.3939

1.333

2.202

0.986

4. Leucocyte count

3.108+

0.240

0.951

0.040+

0.882+

0.920

0.510+

0.628

0.587

-+

* Significant at 0 5 % and $8 0.1 % level. ** - Variances of 2 groups are significantly different. *** + Five subjects in each group.

i

+

12

E. I N O U Y E

t?t

d.

T A B L E VII STATISTICAL EVALUATION

OF

HEMATOLOGICAL

EXAMINATIONS:

SUBJECTS TO REJECTION LIMITS I N

P

COMPARISON

OF

c

GROUP

Numerals in parentheses indicate the period in months in which the significant excess was seen.

C subjects

-

_.

1 1. Erythrocyte count 2. Hb content

-(6-12)*

3. Hb index 4. Leucocyte count

-t(12-24)**

*

**

2

4

3

5

6

__

(6-12)* ++(12-18)**

Significantly exceeding the lower limit at -5 % and - -1 % level. Significantly exceeding the upper limit at +5 % and t 1 % level.

+

T A B L E VIII B O N E A G E BEFORE A D M I N I S T R A T I O N OF T H E D R U G

____

___

~~

Bone age Caye

1

Chronological age

C

1 1 y,

10m

9y,

9m

IOy,

9m

IOy,

Om

P 2

C

P 3

C

P 4

5

C P C

IOy, 1 1 m

P 6

C

8y,

IOm

P .

~.

(years) 13 13 9 9 10 10 10 10 12 12 10 10

Ossification in Pisifovm bones Appeared

Sesamoid bones

Appeared slightly

Absent Absent Appeared slightly Appeared

Appeared slightly

Appeared slightly .

The EEG was recorded by routine frontal, temporal, parietal and occipital monopolar leads of both sides at rest, under hyperventilation and under photic stimulations with frequencies of 3-2O/s. A frequency analyzer of the Hirao type was also used if necessary. Tables IX and X are a survey of the changes in the EEG, and Figs. 1-6 show the basic patterns during 2 years’ course. As seen in Tables IX and X, at 0 month most subjects showed within-normal or borderline-abnormal EEG, and one subject showed slight abnormality. Various dissimilarities between 2 twin subjects of a pair were also seen. The changes in EEG were compared between C and P subjects of a pair, and the evaluation of the effect of the drug was possible in the following 3 cases. Case 4. At 0 month relatively regular and continuous occipital-dominant awaves of 10.5 c/s and moderate amplitude were seen in both twins at rest. Sporadic and continuous 5-6 c/s irregular slow waves at parietal and frontal leads were also

BOVINE BRAIN HYDRATE IN MENTAL RETARDATION

13

indicated in both twins. Build-up by hyperventilation was not marked, and abnormalities such as asymmetry or paroxysmal dysrhythmia were not seen in both twins. Although they were borderline-abnormal, the abnormality in the P subject was slightly more marked in irregularity of continuous occipital a-waves and in the amount of slow waves than in the C subject. After one year an improvement of continuity and regularity of occipital a-waves and a decrease in the amount of slow waves were seen in both twins. In the P subject, however, parietal slow waves were still marked, and the pattern was more irregular by coexistence of 14-15 c/s waves than in the C subject, in whom only few sporadic parietal slow waves remained, and the increase of slow waves by hyperventilation was nearly negative. The C subject thus showed a remarkable improvement, leading to a within-normal EEG at this time. In the following course a similar intra-pair difference was seen. Case 6. At 0 month dissimilarities between C and P subjects were seen in the continuity and regularity of 9-9.5 cjs a-waves, amount of slow waves and dysrhythmia. The EEG of the C subject was within-normal at this time, while that of the P subject was borderline-abnormal. During the first year, a definite change of EEG could not be seen in both twins, except minute changes such as increase in cycle and decrease in amplitude of a-waves. However, at 18 and 24 months continuous occipital a-waves and few slow waves were recorded in C subject, and a remarkable improvement was seen which resulted in a normal EEG corresponding to the age of the subject. In this case an after-effect of the drug was thus suggested. Case 5. At 0 month in both twins 10-11 cjs sharp high amplitude a-waves were present at all leads, and a small amount of slow waves was seen. l n P subject sharp waves and 3 cis slow waves localized at the parietal lead were seen. During the course of the experiment improvements in P subject were indicated: at 6 months a decrease in slow waves activated by hyperventilation, and at 12 months improvement in continuity and regularity of 10-1 0.5 c/s occipital a-waves. These improvements resulted in a less abnormal EEG in P subject after one year of experiment. No improvement of EEG by the drug was seen. Anthropometry was made according to Martin and Saller (1957), and 12 measurements and 8 indices were obtained in each subject. Tables XI and XI1 show the results of statistical tests on these measurements and indices. The sequences of the development in C and P groups (Table XI) are different at the 5 or 0.1 % levels of significance in all length developments except trunk length. Differences were also found in body weight, biacromial breadth and the ratio of body weight to stature at the 5 % level of significance. There is no such significant difference in the measurements ofthe head. On the other hand the results by t-test show no significant difference between 2 groups. Therefore, it is still unknown which group was better i n development, particularly in the length development, The results shown in Table XI1 will be reviewed later. Kano’s Motor Ability Development Test was used. This test is standardized in Japan, and consists of 4 subtests: ( A ) test of equilibrium, ( B ) test of coordination of the whole body, (C) test of coordination of fingers and (D)test of imitation and side differentiation. Total score and scores of the subtests were statistically examined Refercnces p . 39

14

E. I N O U Y E

et al. TABLE C H A N G E S IN

Case

Time of examination

0 Month

C

Diffuse, sharp 10 c/s alpha, moderate amplitude and continuity Sporadic, continuous 4-5 c/s (Fr. Par.) HV: 5 cis bursts (Fr. Par.) Flicker (15 cjs): irregular sp-w (3 C I S ) (borderline)

Increased irregularity of amplitude Sinusoidal 7 c/s (Fr.) HV: build-up (Fr.) Flicker (11-14 c/s): sp-w Others unchanged (markedly aggravated)

Similar pattern to C. Also 3-4 cis (Fr.), 20 c/s HV: sharp waves (Par.) Flicker (1 5 cis) : same as C (borderline)

Slightly decreased amplitude of alpha (Occ.) HV: without change Flicker (11-14 c/s): sp-w (markedly improved)

C

Diffuse, irregular 10 c/s (Occ.), 8 c/s (Par.) alpha, high amplitude Moderate amount of 4 c/s (Par.); 4, 7 c/s bursts (Par. Fr.) HV: build-up after 2 min (borderline)

Decreased amplitude, increased continuity of alpha, developed (OCC.) HV: sharp waves (improved)

P

0cc.-dominant, irregular alpha, high amplitude, smaller amount of 8 c/s waves than C Larger amount of 5-6 c/s, 18-20 c/s than C HV: less marked build-up than C More differentiated than C (borderline)

Almost unchanged Slightly decreased amplitude of alpha (Occ.) (no change)

More irregular sharp alpha, higher amplitude, smaller amount and poorer continuity than P Larger amount of 4-5 c/s than P HV: marked build-up (slightly abnormal)

No build-up by HV Large amount of slow and fast waves at rest, irregular EEG (no change)

Irregular 8-10 c/s alpha (Occ. Par.) Large amount of 4-5 c/s HV: theta bursts after 2 min (Fr.) c(border1ine)

Almost unchanged Slightly developed alpha (Occ. in particular) (improved)

1

P

2

C 3

P

6 Months

alpha

BOVINE BRAIN HYDRATE I N MENTAL RETARDATION

15

IX EEG

(MALE)

12 Months

18 Months

24 Months

Slightly decreased amplitude of alpha HV: same as before Flicker (6, 10.5 cis): sp-w (no change)

More decreased amplitude of alpha Flicker (10 cis): sp-w (no change)

Increased amount and continuity of alpha, marked 9 c/s (Fr.), Fr.dominant Slightly decreased amount of sloa waves Flicker (11.5 cis): sp-w (improved)

Almost same as C Poorer regularity and continuity of alpha than C Sp-w at rest (4-5 cis) (markedly aggravated)

Smaller amount of slow waves than C Diffuse and regular alpha Flicker (10.5, 11.5, 12 cis): sp-w (markedly improved)

Almost same as C Larger amount of slow waves thanC Less marked build-up by HV than C Flicker (10.5, 11.5 c/s): irregular appearance of sp-w (uggruvated)

Irregular 9-10 cis alpha, high amplitude, slowing at Fr. (9 cis) Large amount of diffuse 4-8 cis HV: 3.5 CIS bursts and sharp waves (Par.) (markedly aggravated)

Decreased amplitude of alpha Decreased amount of slow waves Fr.-dominant 8 c/s, slowing at Fr. Better than 6 months (markedly improved)

Increased amplitude of alpha and slow waves Increased amount of slow waves (aggvuvuted)

More regular pattern than C Smaller amount of slow waves than C Still irregular, high amplitude (markedly improved)

Almost unchanged Decreased amplitude of alpha (no change)

Drowsy EEG)

Almost same as P More marked slow waves, fast waves, dysrhythmia than P HV: slowiog (no change)

10 cis alpha, slightly continuous Slow waves, fast waves, dysrhythmia (no change)

References D.

39

(no change)

Increased amount of slow waves, spreading to Occ. HV: sharp and wave complex Flicker (8-8.5 cis): theta bursts (Fr.) (markedly aggravated)

Almost same as P (no change)

No sharp and wave complex by HV Others unchanged (no change)

16

E. I N O U Y E

et al. TABLE C H A N G E S IN

Time Case

of

0 Month

6 Months

examination

0cc.-dominant, regular 10.5 c/s alpha, moderate amplitude Relatively large amount of 5-6 c/s (Par.) Occasional theta bursts HV: slight slowing centering at Par. (borderline)

(Drowsy EEG)

Almost same as C Poorer continuity of alpha than C Larger amount of slow waves than C (borderline)

(Drowsy EEG)

C

Diffuse, sharp 10-11 cis alpha, high amplitude, continuous Small amount of slow waves (Par. OCC.) (normal)

Decreased amplitude of Occ. alpha HV: slightly marked build-up, sharp waves (no change)

P

Almost same as C Lower amplitude of alpha than C Sharp waves (Par.) 3 c/s burst (Par.) (normal)

Almost same as C HV: less marked build-up than C (improved)

C

0cc.-dominant irregular, sharp alpha, continuous Small amount of sporadic 4-5 C/S (Par.) Marked 3-4 c/s, high amplitude (OCC.) HV: theta bursts after 2 min (Fr. Par.) (normal)

P

Diffuse or 0cc.-dominant, irregular 9-9.5 c/s alpha, moderate amplitude, poor continuity Marked 4-5 c/s and dysrhythmia (Par.) Irregular EEG with slowing (borderline)

C

4 P

5

6

(no change)

Increased cycle and continuity of Occ. alpha Others unchanged (improved)

BOVINE BRAIN HYDRATE I N MENTAL RETARDATION

17

X EEG

(FEMALE)

I 2 Months

Occ. regular 10-11 cis alpha, moderate amplitude, continuous Few slow waves HV: small amount of slow waves (markedly improved)

0cc.-dominant 11 c/s alpha, slightly more irregular than C Large amount of 4-5 c/s (Par.) and 14-15 cis, less marked than 0 month HV: increase of slow waves, theta bursts (Fr.) (improved) (no change)

Increased continuity of Occ. 10-10.5 c/s alpha, better continuity than C Sharp waves (Par.) (improved)

Decreased amplitude and increased continuity of alpha Slightly transformed to diffuse alpha (improved)

Occ. irregular 9-9.5 cis alpha, continuous Small amount of sporadic 4-5 cis (Par.) (improved)

18 Months

(no change)

24 Months

Increased regularity of 0cc.dominant 10 c/s alpha Small amount of sporadic slow waves (Par.), less marked than P (no change)

HV: no theta bursts Others unchanged (no change)

Large amount of slightly irregular 11-1 1.5 c/s alpha, increased amplitude Large amount of slow waves as before HV: low amplitude spikes (Par.) (no change)

No sharp waves Others unchanged (no change)

Better continuity of alpha than P Others unchanged (no change)

(no change)

Occasional theta bursts (Fr.) (markedly improved)

(no change)

Increased irregularity of 10 c/s alpha Small amount of slow waves, theta bursts (Fr.) HV: sharp waves (Par.), marked slow waves (Occ.) (aggravated)

9 cis sharp alpha, continuous Well developed EEG (improved)

Large amount of irregular 9 cjs alpha Diffuse 4 c/s theta bursts at rest, high amplitude Others unchanged (no change)

E. I N O U Y E et al.

18

C

Fig. 1 . Development of basic EEG waves (Case 1). F, left frontal; P, left parietal; 0, left occipital lead. Calibrations indicate 1 sec and 50 pV.

c

Fig. 2. Development of basic EEG waves (Case 2).

B O V I N E B R A I N H Y D R A T E I N MENTAL RETARDATION

Fig. 3 . Development of basic EEG waves (Case 3).

P

C

2

Fig. 4. Development of basic EEG waves (Case 4).

19

E. I N O U Y E et al.

20

C

C

--I

Fig. 6. Development of basic EEG waves (Case 6).

21

BOVINE BRAIN HYDRATE I N MENTAL RETARDATION

T A B L E XI STATISTICAL EVALUATION OF ANTHROPOME'IKY

DIFFERENCE BETWEEN

c AND P GROUPS

~~~~

i-values Period in months:

0-12-24

0-12

12-24

0-24

16.76384 1.692 25.0445 0 28.508 $8 4.8880

0.702 0.830 0.728 0.810 0.938

0.024 0.214 1.182 1.310 0.444

0.384 0.836 0.699 0.784 1.294

5.5988 2.379 4.5009:

0.339 0.800 0.231

0.113 1.202 -

0.299 0.646 0.280

0.332

0 0.578 0.852 0.973 0.251

-

Stature Trunk length Height of Sp. 11. Ant. Sup. Lower limb length Upper limb length

1. 2. 3. 4. 5.

6. Weight 7. Chest girth 8. Biacromial breadth 9. 10. 11. 12. 13.

Max. head length Max. head breadth Ear height of head Head girth Sum of 9, 10, 1 I

1.246 1.848 0.313 1.252 1.019

0.325 1.862 0.758 0.601 0.150

14. 15. 16. 17. 18. 19. 20.

211 411 511 514 611 711 811

0.058 0.292 1.091 1.585 6.1805 0.008 0.161

0.461 1.276 0.705 1.354 0.347 0.179 0.684

See:

* and ** in Table VI, p.

-

0.128 0.3 13 0.295 1.247 1.412 0.772 0.059

0.912 0.145 1.310 1.130 0.225

-

-

0.208

0.179

II

(Tables XI11 and XTV). Table XI11 shows that there was no significant difference between C and P groups with respect to the sequences and gains in these scores. The results shown in Table XIV will be reviewed later. Two kinds of intelligence test, Suzuki-Binet and WISC, were periodically performed. Tables XV and XVZ show the results of statistical tests of the IQs. It is seen in Table XV that the sequences of IQ change in the Suzuki-Binet test in the 0-6-12 months' period are different between C and P groups at the 5 % level of significance. The result by t-test shows there is a difference between 2 groups with respect to the gains of the IQ during 6 and 12 months at the 0.1 % level of significance. The average gain in Suzuki-Binet IQ in this period was $2.83 in C group and -1.66 in P group, indicating better IQ development in drug-administered C subjects. The results shown in Table XVI will be reviewed later. Miki's Social Ability Test was used for testing social adaptability. This test consists of various inquiries about working abilities, autonomy and other abilities in everyday life. The total score is converted into Social Ability Age and then into Social Ability Quotient as in intelligence tests. The family members were asked to fill the inquiry form. Tables XVlI and XVIII show the results of statistical tests of Social Ability Quotient. The results were, however, to some extent unreliable, because there were family members who were mentally retarded, and because different family members References p . 39

TABLE XI1 STATISTICAL EVALUATION OP A N T H R O P O M E T R Y : COMPARISON O F

h, h,

c

S U B J E C T S T O R E J E C T I O N LIMITS I N

P

GROUP

-

C Subjects ~

2

I

3

4 ~~

I . Stature

8. Biacromial breadth

6

~

+( 12-24) *

2. Trunk length 3. Height of Sp. 11. Ant. Sup. 4. Lower limb length 5. Upper limb length 6. Weight 7. Chest girth

~~

5

+

-1 (12-24)

*

-( 12-24)*

*

-( 12-24)

**

9. Max. head length 10. Max. head breadth 11. Ear height of head

$- +(12-24)**

+(12-24)*

+t(0-12)* (0-24) *

+

12. Head girth

+@12)*

13. Sum of 9, 10, 11 14. 15. 16. 17.

2/1 4/1 511 5/4

18. 6/1 19. 711 20. 811

See notes in Table VII, p. 12

+ +(12-24)* -( 12-24)

** -( 12-24)

+(12-24) *

-(O-12)**

**

$(O-12)

21

8

TABLE XI11

Ic

c

S T A T I S T I C A L E V A L U A T I O N O F MOTOR A B I L I T Y T E S T : D I F F E R E N C E S B E T W E E N

m

AND

P

GROUPS

P (rr

F-values

I0

Period in months: 04-12

1 . Total score 2. Score, subtest A 3. Score, subtest B 4.Score, subtest C 5. Score, subtest D

See

* and ** in Table VI,

6-12-18

3.236 3.700 2.406 0.813 0.518 p.

3.895 0.019 2.023 1.663 1.825

t-values

12-18-24

1.269 0.019 0.117 0.537 0.284

0-12-24

0 4

1.859

1.990 1.333 0.125

2.945 2.433

0.705

0.067 0.09.5

-

6-12

0-12

12-18

12-24

0-24

0.767 1.668 1.249 0.317 0.126

0.043 0.319 -

0.093 0.105 1.283

1.775 0.078 1.320 1.383 0.597

0.073 0.529 0,064 0.396 0.836

1.071

11

TABLE XIV S T A T I S T I C A L E V A L U A T I O N OF M O T O R A B I L I T Y T E S T : C O M P A R I S O N OF

C

S U B J E C T S TO R E J E C T I O N L I M I T S I N

P

GROUP

C subjects I

1. Total score 2. Score, subtest A 3. Score, subtest B 4. Score, subtest C 5. Score, subtest D See notes in Table VII, p. 12

+(1 2-24)

2

3

4

5

6

-(O-6)

-40-6)

+(6-12) -1- (1 2-24)

-(O-24)

h)

P

T A B L E XV STATISTICAL E V A L U A T I O N OF INTELLIGENCE TESTS: DIFFERENCES BETWEEN

F-values Period in inonfhs: 0 4 - 1 2

6-12-18

c

AND

P

GROUPS

t-values

12-18-24

0-12-24

0 4

6-12

0-12

12-18

12-24

1 . Suzuki-Binet IQ 2. WISC IQ total 3. WISC IQ verbal 4. WISC IQ performance

See

7.3735 1.554 0.201 1.249

* and * * in Table VI, p.

0.099 5.5785

0.181 1.325

0.348 2.208 1.456 1.641

0.098 1.743 1.053 0.963

3.88355

0.404 0.344 0.132 0.269

-

0.357 1.662

1.334 0.804 0.422 0.503

0.383 1.190 0.322 0.869

0-24 -

~

0.049 1.042 0.518 0.517

1.206 1.042 0.712 0.827

11

T A B L E XVI STATISTICAL E V A L U A T I O N OF INTELLIGENCE TESTS: COMPARISON OF

c

Q SUBJECTS T O REJECTION LIMITS I N

P

GROUP

C subjecis 1

1 . Suzuki-Binet IQ 2. WISC IQ total 3. WISC IQ verbal 4. WISC IQ performance

See notes in Table VII, p. 12

2

3

4

++(@I21 i (6-1 2)

5

6

‘c

25

BOVINE BRAIN HYDRATE I N MENTAL RETARDATION

answered the subsequent inquiries. Among the results those at 6 and 12 months are relatively reliable, since the same family members answered at these times. The gains of the Quotient during 6 and 12 months (Table XVII) were significantly different between C and P groups by t-test. The average gains were $8.00 in C group and +2.33 in P group in this period, indicating a possible improvement of social adaptability in C subjects. Besides periodically conducted tests, every subject was evaluated by school teachers in changes of school achievements and behavior at school. The evaluation was made at 15 months, which corresponded t o the end of a semester, after asking class teachers to compare one year’s achievement of a subject with that of a precedingyear. The routine evaluation of school achievements is made in 5 grades, and the distribution to a grade is required to meet the normal distribution. The evaluation of behavioral changes at school was made by asking class teachers at the end of drug administration T A B L E XVII STATISTICAL EVALUATION OF SOCIAL ADAPTABILITY TEST: DIFFERENCE BETWEEN

c

AND

P

GROUPS

t-vafues

F-values

See

Periodin months: 0-6-12

0-12-24

0-6

2.613

1.245

0.271

* and * * in Table VI,

6-12

0-12

2.3745

1.255

12-24

--

0-24 0.575

p. I I

to compare several items of behavior of a subject with those at one year before. Each item of behavior was evaluated in 5 grades from +2, a marked increase, to -2, a marked decrease. Needless to say, the teachers were unaware of which twin received the drug. The changes in school achievements are shown in Table XIX. The total gain in C subjects was +15, and it was 0 in P subjects, but the difference is not significant ( t = 2.08, n = 10). When the change in each school subject was tested in the same way, there was a significant difference between C and P groups in the achievement of science ( t = 2.23, n = lo). The comparison of a change in a C subject to rejection limits in P group is also shown in Table XIX, which will be reviewed later. The results of evaluation of behavioral changes at school are shown in Table XX, which cannot be statistically tested. The total gains were +21 in C subjects and +I0 in P subjects. These items of behavior can be grouped in the following order according to the difference in gains between 2 groups: (I) patience, (2) volition toward studies, interest in studies, general school achievement, number of friends, (3) gentleness, talkativeness, and (4) cheerfulness, activity of motion. Comparison of behavioral changes between 2 members of a pair will be reviewed later. DISCUSSION

The above results and the following discussion are limited to the present experiment, References p.:39

h,

m

T A B L E XVIII S T A T I S T I C A L E V A L U A T I O N O F S O C I A L A D A P T A B I L I T Y T E S T : C O M P A R I S O N OF

C subjects

3

2

1

c

P

SUBJECTS TO REJECTION LIMITS I N

GROUP

*

4

5

6

+(0-6) + +(O-12)

+(6-12)

+(0-24)

See notes in Table VII, p. 12

TABLE XIX

P c (

z 0 c

CHANGES I N SCHOOL ACHIEVEMENT*

.e

Case Schoo I subject

1 C

Japanese Social studies Arithmetic Science Music Drawing-constructing Gymnastics

-1 +1 0 +I -1

Total

-1

*

-1

P -1

0

C

0 +l

+1g 0 -1 +1 +1 +2§§ 0

-1

+4

0 0 +1 -2

P 0 0 0 0

C

P

-1

0 +1

0 0 0 0 +1 0 0

+1

+l

-1

0

rn

4

3

2

0

0 0 0 0 0

C +I§ -1 0 0 +2 0 0 +2

5

P 0 -1

0 -1 +I 0 0

-1

C

6

P

+I§ i-18 +18 +1 +1 0

C

+1

-1

+1Q 0 0 +1 0 i l 0

+6§

-1

$3

0

0 0

0 0 0

The gain in each C subject significantly exceeds the upper rejection limit in P group, !j at the 5 % and $9 at the 1 % level.

z

Total

P 0 0

C +3 0

-1

-1

0 +1 +1 1 2

+3

+4 +5 +4

0 +15

P -1 -1 -1 -1

0 +1 +3

0

e

W

T A B L E XX

0

BEHAVIORAL C H A N G E EVALUATED AT SCHOOL

2

(0-1 2 months)

Case ~

Item of evaluation

2

I* C

P

C

Volition to studies Interest to studies General achievement Gentleness Number of friends Cheerfulness Talkativeness Activity of motion Patience Calmness

$1 +1 0

Total

+3

*

No information.

0 0 0 +I 0 0 0

3

P 0 0 0 0 0 +1

+I 0 -1

0

+I

C

0 0 0

P

+1

0 0 0 0 0 0 0 0 0 0

+3

0

+1

0 0 +1

0 0

C

0 0 +l 0 +1

0 0 0 0 0 +2

_

~

5

4

6

_

P

C

P

C

P

C

0 0 0 0 +I

+l

0 +I 0 0 0 0

0 +I 0 +I

0 0 0 +1 0 0

$2

0

+3 +2 +2 +3

+1 0 +1 +1 +2 +2 +3 -1

+1 +l

+1 0 +1 0 0

0 0 0 +1 +I +I 0

+3

+6

+1 +1 0

0 +3

+2

0 0 0

_

Total

0

+2 +l

+1

+3 +I +3 +2

+7

+3

+21

0 +1

0

P

+1

+ 10

_

_

~

28

E. I N O U Y E et

al.

the present subjects, and the method employed. There is no proof indicating that the results are not due to chance, and that the changes seen after drug administration are to be seen to the same extent in the general population of mentally retarded children. According to the results of clinical observation, the most marked change i n bchavior was seen i n activity. The term activity means the activeness of behavior, the amount of movement or talk. spontaneity and volition, and the term excludes the concept of restlessness or psychomotor excitation due t o lack of inhibition. In the period of 0-12 months of drug or placebo administration, a marked increase in activity was observed in C subjects of Cases 2, 4 and 6, and a less marked increase in Case 5, compared with the respective P subjects. On the contrary, P subjects became more active than the respective C subjects in Cases 1 and 3 in this period. Among C subjects showing increased activity those of Cases 2 , 4 and 5 still showed the same tendency after the administration of the drug was discontinued, though contradictory information was occasionally given by families. In this period C subjects of Cases I and 3 showed an increase in activity compared with the respective P subjects. Tt is thus seen that the administration of the drug brought a favorable effect in 4 and an unfavorable effect in 2 subjects out of 6 . In C subjects of Cases 4, 5 and 6 (all female) maturation of personality accompanied by ego development and by improved sociability was observed. There were 4 C subjects (Cases I , 2 , 4 and 6) with better appetite than the respective P subjects, and one P (Case 5 ) better than C in the initial stage of drug administration, suggesting an improvement in appetite induced by the drug. The above discussion on the effects of the drug is based upon the hypothesis that the development of two members of a MZ pair should be similar and synchronous. If there is a difference in the development within a pair unrelated to the administration of the drug, the comparison of 2 members of a pair at a time may not evaluate the effect of the drug. However, even if the difference is present, the twin individuals with a better development than their co-twins should be distributed at random to C and P groups, since placebo was given at random to a twin. Therefore, if a tendency in behavioral change is disclosed in certain subjects, the effect of the drug can be estimated, even if the difference in the development within a pair remains unknown. This consideration is also applied to other examinations such as EEG, in which the comparison of the twins of a pair had to be used for evaluating the drug effect. A significant decrease in hemoglobin index in C group during the administration of the drug is possibly due to its decrease in C subjects of Cases 1 and 5 during the latter half of drug administration (Table VTT). These 2 individuals are the subjects with no or less marked improvement in behavior. A significant increase in leucocyte count was seen in C subject of Case 1 (Table VT1) after the administration was discontinued. The reason for this increase is not known, and the count was within the normal range (under 7400/ml), and there was no evidence of infection. These findings indicate that there is no stimulating effect of the drug on hematopoietic organs. The findings in the observation on the ossification in carpal bones indicate the lack of accelerating or inhibiting effect of the drug on the ossification.

BOVINE BRAIN HYDRATE I N MENTAL RETARDATION

29

There was little marked abnormality in EEG in the present subjects. This finding may be due to the fact that EEG retardation and dysrhythmia, both of which are seen in mental retardation (Kasamatsu and Tzawa, 19601, tend to be less marked in advanced age. In the present subjects development of EEG during the 2 years’ course and the presence of dysrhythmia resulted in complicated aspects of the records as seen in Tables IX and X and Figs. 1-6, and these complicated aspectsin turn prevented the evaluation of the effect of the drug on EEG in 3 cases. Generally speaking, the drug did not bring more favorable than unfavorable effects in the present experiment. It remains unknown, in several items of anthropometry, what is indicated by significant differences in the sequences of the development between C and P groups. Fig. 7 shows the averages in 2 groups of each of 7 items with a significant difference in the developmental sequences between 2 groups. In 5 out of 7 items nearly or exactly the same pattern of average development is seen, and the average of P subjects equals or dominates that of C subjects at the end of drug administration. This tendency was maintained after the administration of the drug was discontinued. Other 2 items are lower limb length and height of spina iliaca anterior superior, both of which are related to the length of legs. In both measurements the average of C subjects having been lower than that of P subjects caught up with that of P subjects at 12 months, but again fell behind that of P subjects at 24 months. This observation seemingly indicates that the development of legs was temporally accelerated by the drug. However, the development shows no parallelism with stature and upper limb length, which showed a difference in developmental sequences between 2 groups and which are the indices of length development of the whole body. Fig. 7 also shows that C subjects made a poor development in body weight, biacromial breadth and the ratio of body weight to stature, which are the indices of breadth development of the whole body. Fig. 8 shows the average percentage deviation* of the above-mentioned 7 items in each pair. Instead of absolute values of the differences between 2 members of a pair, the value C-P was used for the calculation. The increase in the average percentage deviation thus indicates a more superior development in C subject than P subject, whereas a decrease indicates a more inferior development in C than P. It is seen in Fig. 8 that C subjects of Cases 2 and 4 clearly showed an inferior development than the respective P subjects during the administration of the drug. In other C subjects a superior or an equal development was shown compared with the respective P subjects in this period. The 2 C subjects with inferior bodily development are, together with C subject of Case 6 , those who showed more or less clear improvement in behavior in other examinations. According to Table XTT, C subjects significantly exceeded the rejection limits of the P group in the measurements of the head as well as in those of the whole body. A-B

. 100, when A and B are the values of a measurement in 2 memA+B bers of a twin pair (A :, B). Average percentage deviation is the average of percentage deviations of more than 2 measurements in-a pair of twins. *

Percentage deviation is

References p.!39

30

E. I N O U Y E et

al.

3 , Height of Sp. 11.

4 . Lower I.imh

A n t . SUP.

Length

5 . Upper Limb Length

I

(Months1 iManthal (Months1

0

I2 *Months'

24

8 . Biacromial Breadth

6 , Weight

lE.M'eight/S tature

I

C Suhjrcls

I' S u h j e c l s

, Monl h i

I

Fig. 7. Averages in C and P groups of 7 anthropometric items significantly different between 2 groups.

During drug administration ear height of the head (Case 2) and head girth (Case 4) in C subjects increased. The measurement of ear height of the head is not easy and not always reliable. However, it is interesting that these 2 C subjects are among those who showed delayed development of the head (head length in particular) compared with the standard (Tables I and I]), and among those who showed a more or less clear improvement of behavior in other examinations. The increase in ear height of the head in C subject of Case 2 is still significant, if the period of 0-24 months is taken (Table XU), and this seems to indicate that the increase is not a temporary one limited to the period of drug administration. Two kinds of statistical test on motor ability scores showed no difference between C and P groups in any period (Table XTIT), and no effect of the drug was indicated. According to Table XIV all significant excesses of the gains in motor ability scores in C subjects were below the rejection limits of P group, if a period starting from 0 month is taken. In the period of 6-12 months, however, C subject of Case 6 showed a

BOVINE BRAIN HYDRATE IN MENTAL RETARDATION

31

+3.0

+2.0

+1.0

0

-1.0

-2.0

-3.0 I

I

I

0

12

24

(Manlhsl

Fig. 8. Average percentage deviations of 7 anthropometric items significantly different between 2 groups. Numerals in parentheses indicate case number.

greater gain in Subtest B (test of coordination of whole body) than P group. In addition C subject of Case I showed, in the period of 12-24 months, greater gains in total score and in score of Subtest D (imitation and side differentiation) than P group, indicating a parallelism with the finding in clinical observation on behavioral changes. These findings indicate that the effect of the drug, if any, occurred after 6-months' administration, and in some cases a favorable effect occurred after the administration was discontinued. The significant difference in the sequences of Suzuki-Binet IQ between 2 groups in the period of 0-6-12 months is well explained by the highly significant difference in the gains in the IQ between 2 groups in 6-12 months' period indicated by t-test (Table XV). This finding agrees with the findings that sequences of total WISC IQ were significantly different between 2 groups in the period of 6-12-18 months, and that in C subjects the average of the gains during 6-12 months in total WISC IQ, verbal TQ and performance IQ were +7.83, $-4.83 and +8.50 respectively, while in P subjects they were f3.50, $1.50 and +5.50 respectively. These findings indicate that marked improvement of IQ in C subjects was obtained during the latter half of one year's drug administration. There is no indication, however, that the improvement in IQ was sustained after the administration was discontinued. Longer administration may be necessary, if a long lasting effect of the drug is desired. References p . 39

32

E. I N O U Y E

er al.

According to Table XVI significant excesses of Suzuki-Binet 1Q gains over the rejection limits of P group are seen in C subjects of Cases 4 and 6. The excesses occurred in both periods of 0-12 and 6-12 months in Case 4, and in both of them the gains were superior to those in P group. In Case 6 a significantly greater gain was observed in the period of 6-12 months, while the gain was negative in the period of 0-6 months. These findings again indicate that the effect of the drug on IQ development is present, if at all, only after 6-months’ administration. Moreover, the significant differences in sequences or gains of TQ between 2 groups by F- and t-tests are mainly due to the marked increase in 2 C subjects. Among the results of the social adaptability test, the changes in the quotient in the period of 6-1 2 months were relatively reliable. There were significantly greater gains in C group than P group in this period. Thus it might be possible to expect an improvement in social adaptability by the administration of the drug, were it continued beyond 6 months. C subject of Case 2 (Table XVIII) showed an improvement in the test quotient significantly exceeding the rejection limit of P group, and this may contribute to the above-stated difference between 2 groups. The finding in Case 6 in Table XVIII is unreliable, since a different family member answered the inquiries at 0 month. The reason for the significant improvement in the school achievement in science in C group is not known. There were C subjects who showed significant improvement in achievements in Japanese, social studies, arithmetic, drawing and constructing or total achievement, when compared with the rejection limits of P group. There was no single C subject who showed a significant decrease in school achievements. Although it is not significant, the improvement in the achievement in gymnastics was more marked in P than C subjects, and it is suggested that, together with the results of motor ability test, the drug does not improve the skill in gymnastics, and that the drug has no marked stimulating effect on the motor functions. According to the evaluation of behavior by school teachers, C subjects were reported to have gained particularly in patience, and P subjects in cheerfulness and activity of motion. This result suggests that in C subjects hyperactivity was inhibited and will power was developed. This interpretation is in agreement with the above possibility of the drug having no marked stimulating effect on motor functions, and also with the findings in clinical observation, leading to the conclusion that the drug possibly has an accelerating effect on the development of the superstructure of personality, which inhibits the basic and primitive personality functions such as drive and emotion. In the following paragraph the findings will be summarized, and the effect of the drug will be discussed in each diagnostic category. Case 1. According to the results of clinical observation of behavioral change, P subject became more active than C subject during the administration of the drug. After it was discontinued, C became more active than P. Corresponding to this change, the total score and the score of a subtest of the motor ability test increased in C after the administration was discontinued. There was no clear gain by C subject in the intelligence test, social adaptability test or school achievements. Also the intra-

BOVINE BRAIN HYDRATE I N MENTAL RETARDATION

33

pair difference in EEG changes was not clear, and this case showed least clear changes in behavior and functions of the central nervous system. In accord with this finding, there was no clear change in physical examination except decrease in hemoglobin content during the drug administration, and there was no anthropometric item with significant excess over the rejection limits of P group. At the beginning of the experiment the developmental difference between two members was little (Table I), and it is suggested that the twins were less susceptible to environmental influences. Both twins of this case were diagnosed as subclinical epilepsy, and their physical developments were normal or better than normal. They had poor school achievements possibly due to their epileptic personality. The drug is seen to be ineffective in this kind of mental retardation. Case 2. C subject of this case showed more marked increase in activity than P subject during entire course of the experiment, and the increase in activity was accompanied by an improvement in Social Ability Quotient during the latter half of the drug administration period. School achievements in Japanese, and drawingconstructing were improved, and he was reported to have improved in volition and interest in studies, but reported unchanged in patience and cheerfulness; while P subject showed no change in the former 2 items and a decrease and an increase in the two latter items respectively. The most remarkable physical change in C subject was the increase in ear height of the head significantly exceeding the rejection limit of P group during the drug administration as well as during the entire course of the experiment. Breadth development of body in C subject during the administration might have been delayed, because, after it was discontinued, an increase in biacromial breadth was indicated as well as in the ratio of that to stature. Although improvements in EEG, motor ability and IQ were not seen in C subject, the above improvements suggest the possibility of a more accelerated personality maturation in C subject than P subject. These improvements ran parallel with a n increase in ear height of the head, although there was no indication of an improvement in physical development during the drug administration. At the beginning of the experiment a great intra-pair difference in physical developments was indicated (Table I), suggesting a susceptibility of the twins to environmental influences. Both twins had been delayed in physical development and personality maturation, and their school achievements were poor possibly due to prenatal retardation of development and due to unfavorable family environment through the neglect by parents. The drug seems to be effective, to some extent, in improving the behavior of this kind of mental retardation. Case 3. C subject became less active during the drug administration, and more active after the drug administration was discontinued than P subject. According to the evaluation of behavioral change at school, C was reported to have become gentler, more talkative and calmer than before. However, there was no significant excess of gains in intelligence tests, motor ability test, social adaptability test or school achievements in C subject over the rejection limits of P group. There was also no clear intrapair difference in EEG change. C subject was one of the cases with least physical change, except minute changes such as slight anemia and significant decrease in References p . 39

34

E. I N O U Y E et (11.

biacromial breadth after the administration was discontinued. This pair had shown no great difference in physical developments at the beginning of the experiment (Table I), and this may indicate the possibility of the twins not being susceptible to environmental influences. The twins were both morons of the category of subcultural mental deficiency. The drug seems to be ineffective in this kind of mental retardation. Case 4 . C subject became more active than P subject after 6 months’ drug administration, and she improved in sociability based upon ego development and maturation of personality. The difference between the twins was still observed after the drug administration was discontinued. Running parallel to these changes, SuzukiBinet IQ showed a marked increase in the period of 0-12 months, exceeding the rejection limit of the control P group. When the period was divided, the increase in IQ was seen in the latter half of the period, 6-12months. After one year of drug administration a marked decrease in slow waves of EEG in C subject was seen, and the improvement of EEG persisted after the administration was discontinued. In addition C subject showed significant improvement in school achievement in Japanese, and it was reported by her school teacher that she was unchanged in cheerfulness and activity of motion, while her co-twin increased in these behavioral items. The most marked change in physical examination was the increase of head girth during the drug administration. She also showed a decrease in the ratio of biacromial breadth to stature during the drug administration and a marked increase in maximum head breadth after the administration was discontinued. On the other hand there was no significant excess of gains over the rejection limits of P group in WISC, motor ability scores and hematological tests in C subject of this case. The report by the school teacher was contradictory t o the result of clinical observation on behavioral change with respect to activity. A family member also reported that P subject became more active than C at 18 months. This contradictory information suggests the possibility, that in C subject hyperkinesis was more inhibited and the development of will-power was more accelerated compared with those in her co-twin. This possibility is also indicated in the record at school, in which C improved in the volition toward studies at around the end of drug administration. It is thus possible to summarize the findings and information on behavioral changes as follows: in C subject the drug appeared t o accelerate the development of the superstructure of personality, which resulted in an inhibition of psychomotor functions and in a more organized behavior. The improvement of behavior in C subject ran parallel with the improvement in EEG and with the increase in head girth. With respect to EEG, there was no dysrhythmia, and many slow waves were seen at parietal leads while a-waves at occipital leads were well developed before the administration of the drug. This indicates that there was at first a localized primary retardation of EEG development. During drug administration the parietal a-waves improved markedly. This indicates that slow waves related to the localized retardation of brain maturation were markedly improved. Although the above 3 results, improvements in behavior, EEG and development of head, were obtained independently, the possibility of these changes being merely

BOVINE B R A I N H Y D R A T E IN MENTAL R E T A R D A T I O N

35

due to chance cannot be denied. Nevertheless, the changes in EEG were clearest among 6 pairs of subjects, and the head girth is one of the most unchangeable items of anthropometry at these ages. The above findings and discussion suggest that the drug, at least as far as the present case is concerned, had the effect of improving the retardation of brain maturation. This case had shown a great intra-pair difference in physical development at the beginning of the experiment (Table I I), and it is suggested that the susceptibility to environmental influences may be one of the reasons for improvement in behavior and brain functions. The twins both had normal intelligence, and physical and personality retardation were caused by birth disorders, physical weakness at birth and other factors. This kind of mental retardation was improved by administration of the drug. Case 5. In C subject improvement in school achievements was most remarkable among all subjects. Total school achievement and achievements in Japanese, social studies and arithmetic were shown to have improved over the rejection limits of P group. The result of clinical observation showed that C subject became more active and more matured in personality than P subject during the administration of the drug. However, the difference in behavioral changes between two subjects was not marked, and the difference had already been seen at the beginning of the experiment (Table 11). The school teacher reported that C improved in volition toward studies and became more patient. There was no significant excess of gains over the rejection limits of P group in intelligence tests and the social adaptability test. Negative gains were indicated in the total score (0-6 months) and in the score of a subtest (0-24 months) of the motor ability test. Inferior development in basic EEG waves was also indicated in C subject. Physical changes were: decrease (6-12 months) and increase (12-18 months) in hemoglobin content; increases in trunk length, the ratio of that to stature and maximum head breadth; and decreases in biacromial breadth and the ratio of upper limb length to stature (12-24 months). Despite the most marked improvement in school achievements and slight improvement in clinically observed behavior and behavior at school, the improvements were not so clear as in Case 4, and the results of other examinations do not run parallel with these improvements. The C subject had had a physical handicap due to congenital dislocation of the hip joint, which possibly affected the evaluation of behavior and physical examination. Consequently clear-cut interpretation of test results is difficult, and the evaluation of the effect of the drug remains undetermined. There is also a possibility that the drug is ineffective in improving behavior and brain functions in subcultural mental deficiency, which is the diagnostic category of this case. Case 6. C subject became more active than P subject during one year’s drug administration. The tendency of personality maturation was also seen in C subject in this period, but the changes in behavior became obscure after the administration was discontinued. A decrease of Suzuki-Binet IQ was indicated in C subject during the first half, but its increase was indicated during latter half of drug administration. Running parallel to the TQ change, the total score of the motor ability test showed a decrease during the first half of the period, and a subtest of the motor ability test Referrncrs p . 39

36

E. I N O U Y E

et al.

showed an increase during the latter half of the administration. The class teacher reported that C subject showed increases in interest toward studies, number of friends and patience, but activity of motion was unchanged while her co-twin showed an increase in this item. Among school achievements only Japanese showed improvement. After the administration was discontinued, the development of basic EEG waves and a decrease of slow waves were observed. Among anthropometric items the ratio of biacromial breadth to stature increased during the drug administration. There was no significant change in blood tests, and the results in social adaptability test in this case were ufireliable. Despite temporary falls in IQ and motor ability score, both were improved in the latter half of drug administration, and if the entire year is taken, improvements were seen in clinically observed behavior, behavior at school and school achievements. The improvement in EEG was seen later still. The relative decrease in activity of motion reported by the class teacher is, as in Case 4, possibly due to the better development of the superstructure of personality in C subject than her co-twin. The twins had shown no great difference in physical developments at the beginning of the experiment (Table ll), and they are possibly not susceptible to environmental influences. Both twins represented exogenous personality retardation mainly due to prenatal retardation of development, and intelligence was moron or borderline. The drug was effective to some extent in this type of mental retardation. In reviewing the above summaries and discussions, no or hardly any effect of the drug was observed in subclinical epilepsy (Case I) and in subcultural mental deficiency (Case 3). Case 5 is also a subcultural mental deficiency, but the evaluation of the drug effect was impossible because of a physical handicap in a twin. The clearest effect of the drug was seen in Case 4, and a less clear effect in Cases 2 and 6 . All these subjects had exogenous mental retardation with an intelligence better than moron or than borderline, and they showed retardation of personality maturation accompanied by retardation of physical development, in particular retardation of the development of the head. The drug seems to be effective in improving behavior and brain functions in this particular category of mental retardation. A question arises whether the primary effect of the drug is to improve the general physical retardation, whereas the improvements in behavior and brain functions are a secondary effect. It was shown, however, that the drug had at least no marked stimulating or accelerating effect on anthropometry of the whole body, motor ability, psychomotor functions and hematopoietic organs, but it had rather an inhibiting effect on these functions or morphological traits. This seems to indicate a difference between the action of the drug and that of glutamic acid alone. The mechanism of action of the drug, though still unknown, may bear a relationship to a more natural spectrum of the substances in brain tissue in the present drug. In 2 of these 3 cases improvement in EEG and increase in head measurement were seen in each examination. It might be possible to postulate that bovine brain hydrate has a selective effect of improving the retardation of brain development or maturation. The authors are aware that this postulation is improbable if the present results were due to chance.

BOVINE BRAIN HYDRATE I N MENTAL RETARDATION

37

Among the present subjects there were only 2 pairs of subcultural mental deficiency, the most common type of mental retardation. The question arises whether the present series of subjects includes a greater proportion of exogenous personality retardation than occurs among the general population of mental retardation. Also there is the question whether the present results would similarly be obtained in the general population. The first question cannot be answered precisely, since there are no reliable data on the frequency of exogenous personality retardation among single-born mentally retarded children. However, there are positive findings as to the inferior early development of intelligence in twin individuals (e.g. Berg and Kirman, 1960). Also pregnancy and birth disorders often accompany twinship, and pre- and postnatal physical development is often delayed in twin individuals. Therefore, twin individuals may tend to be inferior in mental and physical early development, and the present series may include more exogenous personality retardations than among single-born mentally retarded children. On the other hand, since no qualitative difference between twin and non-twin individuals has been indicated, the same effect of the drug may be expected to be obtained in the same type of mental retardation in the general population, though it may be impossible to expect the same extent of the effect, 3 out of 6, even were a similar experiment conducted among the general population of mentally retarded children. SUMMARY

A non-selected series of same-sexed twins, who were attending classes for average children at primary schools in the Tokyo Metropolitan area, and who were below a certain level of intelligence at schools, was invited to volunteer in an experiment. One twin in each of 6 monozygotic pairs (the ages were between 8 years 10 months and 12 years 1 month at the beginning of the experiment) was orally given Ceremon, which mainly consists of bovine brain hydrate, and the other twin was given placebo, for one year by the double blind method. The dose of the drug was between 7 and 12 tablets per day. For an additional year both twins were given placebo, and during 2 years various tests were periodically conducted. All measurements and indices were statistically examined in 3 ways. The diagnostic categories were the same in both twins of every pair: one pair of subclinical epilepsy with epileptic personality (normalborderline intelligence), 3 pairs of exogenous personality retardation (all above moron) and 2 pairs of subcultural mental deficiency (all moron). Comparison of the group of 6 drug-administered subjects to that of 6 control subjects, and the comparison of a drug-administered subject to its control co twin or to the control group were made, and the following results were obtained. Clinical observations on behavioral and physical changes showed that in 4 drugadministered subjects activity was increased over that in their co-twins. Three subjects still showed the same tendency after the administration was discontinued. Also in 3 of them an improvement of sociability and development of superstructure of personality were indicated. In the remaining 2 pairs control subjects showed a more favorable change as to activity than their drug-administered partners. Suzuki-Binet References p . 39

38

E. I N O U Y E

et al.

IQ in the drug-administered group increased during the latter half of the administration at a high significance level. This finding agrees with that in WISC IQs, but the IQ increase did not last after the administration was discontinued. Social Ability Quotient, though somewhat unreliable, showed a significant increase in the drugadministered group during the latter half of the administration. School teachers reported that the most marked changes were the increase in patience in drug-administered subjects, and increases in cheerfulness and activity of motion in control subjects. It was concluded that in drug-administered subjects the development of the superstructure of personality inhibiting hyperkinesis was accelerated. The drugadministered group also showed a significant increase in achievement in science, and the improvements in various school subjects were significantly greater in a number of drug-administered subjects than in the control group. In no school subject was there a decrease in achievement in the drug-administered subjects. With respect to motor ability, 2 drug-administered subjects showed significantly poor gains during the first half of the drug administration. After the administration was discontinued, one subject showed a significantly better gain compared with the control group. There was no significant difference between 2 groups in the motor ability test. Improvement in EEG was seen in 2 drug-administered and in one control subjects during the administration or after it was discontinued. There were significant differences in sequences of the development in several anthropometric items except those of the head measurements. All but two of the items related to leg development showed better development in the control group than in the drug-administered group. This difference took place during the drug administration, and it is suggested that bovine brain hydrate has an inhibiting effect on the development of the whole body except that of the head. During the administration of the drug a significant decrease in the hemoglobin index was indicated in the drug-administered group compared with the control group, and bovine brain hydrate had an inhibiting effect on hematopoietic organs. Ossification in carpal bones showed no difference between two members of a pair, and no marked pathological finding in blood and urine tests was indicated, except occasional urine protein or mild anemia in 2 drug-administered and 3 control subjects. The effect of the drug was evaluated in each pair of twins, and the following findings were obtained. Among 6 drug-administered subjects 3 exogenous mental retardations due to pre- or para- or post-natal agencies were shown by various tests to have improved in behavior. Among them the change was most marked in one subject with personality retardation and normal intelligence. An acceleration of the development in the superstructure of personality was suggested in these 3 subjects. An improvement in EEG retardation was indicated in 2 of the 3 subjects. Significant increases over the rejection limits in the control group of head measurements were also indicated in 2 of the 3 subjects. It is suggested that bovine brain hydrate may have a selective effect in improving the retardation of brain maturation or development, and that this effect may be one of the reasons for the improvement in behavior in these subjects. On the other hand, no improvement in behavior or brain functioning was seen in a subject with subclinical epilepsy and with poor school achievements due to epileptic person-

BOVINE BRAIN HYDRATE I N MENTAL RETARDATION

39

ality, and in a subject with subcultural mental deficiency. In another subcultural mental deficient the effect of the drug remained undetermined because a physical handicap affected the evaluation of test results. There is no proof that the above results are not due to chance. It is possible that a similar effect would be obtained in single-born subjects of the same diagnostic category in which a clear effect of the drug was seen in the present experiments. Susceptibility of individuals to environmental influences is also discussed. ACKNOWLEDGEMENT

The authors are greatly indebted to Kaken Yakukako K. K. for courteously offering the samples of the drug. The actual data of the experiment, not appearing i n this article, may be obtained by writing to that company. REFERENCES BERG,J. J., AND KIRMAN, B. H., (1960); The mentally defective twin. Brit. med. J . , 1 , 1911-1917. CHOROSCHKO, W. K., (1912); Die Reaktionen des Tierorganismus auf Einverleibung von Nervengewebe. Moskau. Cited by G. Harrer. Dtsch. med. Wschr., 79 (24), 983-985. GREULICH, W. W., AND PYLE,S. I., (1959); Radiographic Atlas of Skeletal Development of the Hand and Wrist.2nd Ed., Stanford, Calif., Stanford University Press. HARRER,G., (1954); uber die biologischenWirksamkeit von Gehirnhydrolysaten. DtJch. med. Wschr., 79 (U),983-985. HETZEL,H., (1954); Die Wirksamkeit von Gehirnhydrolysaten beim hypoglykamischen Koma. Munch. med. Wschr., 47, 1389-1391. INOUYE, E., (1962); Zygosity diagnosis of Japanese twins by Essen-Moller's formula (11). Soseiji No Kenkyu (Studies on Twins) III.T. Fujita, Editor. Tokyo, Nihon Gakujutsu Shinkokai (pp. 1-1 3) (in Japanese). INOUYE, E., (1963); Effect of cerebrohydrate on mentally retarded children. A co-twin control. Proc. 2nd Intern. Congr. Mental Retardation, Part II. 0. Stur, Editor. New York and Basel, Karger (pp. 147-148). KASAMATSU, A., A N D IZAWA,S., (1960); Intelligence, Mental Deficiency and EEG. Seishin Zgaku Saikin No Shimpo (Recent Advances in Psychiatry) I ] . Y . Uchimura et al., Editor. Tokyo, lshiyaku Shuppan (pp. 281-296) (in Japanese). MARTIN,R., AND SALLER, K., (1957); Lehrbuch der Anrhropologie. Stuttgart, G . Fisher Verlag. W., AND WALKER, J. W., (1947); Effect of L(+)glutamic acid in hypoglycaemia. MAYER-GROSS, Nature, 160, 334. PRICE,J. C., WAELSCH, H., AND PUTNAM, T. J., (1943); oL-Glutamic acid hydrochloride in treatment of petit ma1 and psychomotor seizures. J. Amer. med. Ass., 122 (17), 1153-1 156. TOFUKUJI, C., (1957); On the physical development in pupils and students at Tamagawa Gaguen. Tokyo Jikeikai Ikadaigaku Kaibogaku Kyoshitsu Gyosekishu X VI (in Japanese). Y., AND TATEYAMA, K., (1961); GABOB (y-amino-p-hydroxyWADA,T., GOTO,A,, FUKUSHIMA, butyric acid) treatment in epilepsy. Foliapsychiat. neurol.jap., 15 (4), 327-335. ZIMMERMAN, F. T., BURGEMEISTER, B. B., AND PUTNAM, T. J., (1946); Effect of glutamic acid on mental functioning in children and in adolescents. Arch. Neurol. Psychiat. (Chic.),56(5), 489-506

40

Hippocampal After-Discharge and the Mode of Action of Psychotropic Drugs * TOSHIO I S H l K A W A , Y O S H l H I S A S A D A N A G A , S A D A O K A T S U T A , JUN-ICHI TSHlYAMA A N D T A T S U O KOBAYASHI Department of Pharniacology, School of Medicine, Chiba University, Chiba (Japan)

INTRODUCTION

As a result of many studies on the effects of psychotropic drugs, it is now recognized that these drugs have both facilitatory and inhibitory effects on the central nervous system, and also that they have some effects on the limbic system. Though the hippocampus had been considered the center of smell by many investigators, recent works have shown that olfactory discrimination and olfactory conditioned reflexes were not affected by ablation of the hippocampus (Swam, 1934; Allen, 1941). Although details of the functional role of the hippocampus are not yet evident, it has been reported that this structure probably is concerned in emotion. Moreover, the hippocampus produces repetitive discharges (so called hippocampal after-discharge) on low boltage electrical stimuli (1-2 V) (Gibbs and Gibbs, 1936; Morin and Green, 1953; Liberson and Akert, 1955; Feldberg and Fleischhauer, 1963); the animals are objectively in arrest of motion without showing convulsions during these discharges. Consequently, our study was undertaken to observe the details of hippocampal after-discharge and to analyse the mode of action of psychotropic drugs during these discharges. In addition, a pharmacological analysis of hippocampal after-discharge was also made. METHOD

Experiments were performed on 70 adult albino rabbits of either sex, weighing from 2.5 to 3.2 kg, in acute preparations. The animals were immobilized with flaxedil under artificial respiration and fixed to the stereotaxic instrument. Cortical activity of the brain was recorded bipolarly via stainless steel electrodes screwed into the parieto-temporal area of the skull. Bipolar subcortical electrodes of insulated copper wire (0.4 mm in diameter) were arranged in two parallel rows.

* Part of this study was presented at the IV. Meeting of the Collegium Internationale Neurnpsychopharmacologicuni (Birmingham, England) on August 3 I -September 3, 1964.

A N A L Y S I S OF H I P P O C A M P A L A F T E R - D I S C H A R G E

41

Bipolar stimulating electrodes also consisted of insulated copper wire (0.2 mm in diameter), and were encased in stainless steel syringe needles except for their tips. These electrodes were positioned subcortically according to Sawyer’s coordinates (Sawyer et al., 1954). Square wave shocks of 1 msec duration and at a rate of 50 c/s for 10 sec were derived from a Nihon Kohden stimulator. Voltage ranged from 1-10 V according to the sensitivity of each individual rabbit. The positions of all subcortical electrodes were ascertained histologically. The recording instrument used was a sixchannel San’ei electroencephalograph. Electrolytic lesions in the amygdaloid nuclei were induced with a high-frequency (500 kc) coagulating current.

CONTROL

PRIMARY DISCHARGE

a f t , 60min

-

SECONDARY DISCHARGE

Fig. 1, Effect of reserpine on hippocampal after-discharge. Typical ‘primary discharge’ and ‘secondary discharge’ are shown. A = Control (before injection); B and C = 60 min after injection of reserpine 1 mg/kg i. v. C continues to B. Right half of C indicates the response after 200 sec of electrical stimulation. The ‘secondary discharge’ occurs following the ‘primary discharge’. The stimulating electrodes are inserted into the right dorsal hippocampus 3 mm from the recording electrodes. Cortex = neocortex (parieto-temporal region); R F = midbrain reticular formation; L. and R.Arnyg = left and right amygdaloid nuclei; L. and R.HPC = left and right dorsal hippocampus. ES 4v: electrical stimulation of 4 V (0.1 msec, 50 c/s for 10 sec). Rifcrences p . 52/53

42

T. I S H I K A W A et al.

All drugs except acetylcholine were administered intravenously. Acetylcholine was iiijected via a polyethylene tube inserted into the lateral ventricle. BASIC PHENOMENA

At first, in these pharmacological experiments, we undertook to analyse the phenomenon of the hippocampal after-discharge physiologically.

I. Characteristics of hippocampal after-discharge High amplitude and polymorphic types of after-discharge were generally produced by electrical stimulation of the hippocampus. The threshold is usually very low. Stimuli of 1 msec duration, 50/sec, from 1 to 4 V for 10 sec, produced the after-discharge for varying durations, from a few seconds to 10 min or more; but, in the same individual, after-discharge was elicited constantly by the same electrical shock. Continuous spike discharges or spikes and wave? were most frequently seen, and in many cases these phases alternated. In a few cases, however, only a phase of spikes and waves was observed. The discharge usually propagated to the opposite hippocampus and many cortical and subcortical structures. Propagation to the neocortex was more readily found in the parieto-temporal and occipital areas. Propagation of after-discharge was also recorded from some subcortical structures such as fornix, mammillary body, anterior thalamic nuclei and hypothalamus. In the amygdala, however, no active seizure discharge was observed. The above described series of seizure patterns are designated as ‘primary discharge’ (Fig. IA). Doses of 0.5-5 mg/kg of reserpine or 1 mg/kg of chlorpromazine given intravenously produced another late active seizure discharge from the amygdala, following the above mentioned ‘primary discharge’. Small spikes recorded from the amygdala during ‘primary discharge’, gradually increased their frequency and amplitude, then propagated to the septa1 nuclei and the midbrain reticular formation. In the following stage, this high amplitude seizure discharge was recorded from all areas of the cerebrum including areas from which ‘primary discharge’ was observed. In this paper, the series of these patterns which are accelerated by reserpine or chlorpromazine are called ‘secondary discharge’ (Fig. 1B and C). Furthermore, salivation, defecation and other autonomic responses were frequently seen during this phase.

II. Relation between hippocampus and amygdaloid nuclei The threshold for eliciting the after-discharge is lower in the hippocampus than in the amygdala, the hippocampal discharge in the form of spike firing usually started immediately after electrical stimulation. In contrast, the amygdaloid seizure discharge appeared gradually and later on reached the maximal amplitude. At this stage, some responses of the autonomic nervous system were observed, as in the ‘secondary discharge’ of the hippocampal seizure.

ANALYSIS OF HIPPOCAMPAL AFTER-DISCHARGE

43

Both reserpine, at a dose of 0.5-5 mg/kg, and chlorpromazine, at a dose of 1 mg/kg, accelerated the amygdaloid seizure and decreased its threshold voltage (Figs. 2 and 3). Other psychotropic drugs and doses higher than 1 mg/kg of chlorpromazine, however, had no effect on amygdaloid seizure. On the other hand, thiopental sodium depressed amygdaloid seizure completely. Reserpine (0.5-5 mg/kg), or chlorpromazine (1 mg/kg) induced no ‘secondary discharge’ in subchronic and chronic preparations in which the amygdaloid nuclei were electrically coagulated bilaterally, I0 days or more prior to administration of the drugs. These observations suggest that the ‘secondary discharge’ presumably originates from the amygdala. III. Relation between hippocampal after-discharge and the reticular activating system

When the reticular formation was stimulated electrically (enough to produce the arousal response electroencephalographically) immediately before, after and during stimulation of the hippocampus, no change in hippocampal after-discharge was observed. These results suggest that there is no relation between the hippocampal afterdischarge and the reticular activating system. IV. Conditions of electrical stimulation ,for obtaining hippocampal after-discharge

Various durations and frequencies of stimulation under conditions which included a time of 10 sec and voltages of 1-5 V were studied. The results are as follows: (a) Frequency. A stimulation of 50/sec was the most effective of various stimuli ranging from 10 to 200/sec. (b) Duration. Stimulation with a duration of less than 0.5 msec did not produce an after-discharge. (c) Stimulation of 1 msec duration elicited a long sustained hippocampal afterdischarge; the duration of the seizure discharge was, however, shortened by stimulation of more than 2 msec. Accordingly then, 1 msec was used as the duration of choice for stimulation in our experiments. (d) Interval. Intervals between electrical stimulations were 15 min or more. (e) Stability of the hippocampal after-discharge. Under the conditions employed in our experiments, the parameters mentioned above (threshold, duration and pattern of the after-discharge) are surprisingly stable. RESULTS

( I ) Thiopental sodium. Doses of 5-20 mg/kg of thiopental sodium completely depressed the hippocampal after-discharge on electrical stimulation at the threshold voltage (Fig. 4). ( 2 ) Chlorpromazine. Chlorpromazine 1 mg/kg prolonged the duration of the afterdischarge and elicited the ‘secondary discharge’, but had no effect on the threshold. Rcferencrs p . 52/53

Fig. 2. Effect of chlorpromazine on amygdaloid after-discharge. (control recording of Fig. 3). A and 13 Immediatcly aftcr elcctrical stimulation. C m n id D = 240 and 800 sec after electrical stimulation. SP = septum.

a f t ,120mi n

FORTE x

ES 4 V

-v-Tb-w$w\w DF

-RF SP

Fig. 3. Effect of chlorproinazine on amygdalnid after-discharge (120 min after injection of chlorprornazine 1 mgjkg i.v.). A and B : Immediaiely after electrical stirnularion; C and D : 180 and 600 sec after electrical stimulation. Thrcshold voltagc decreased from 6 to 4 V.

46

T. I S H I K A W A et al.

Fig. 4. Effect of thiopental sodium on hippocampal after-discharge. A = Control (before injection); B 20 min after injection of thiopental sodium 10 mg/kg i.v. no after-discharge is observed even a t 10 V of electrical stimulation ( 5 times control threshold); C = 40 min after injection, complete recovery is shown.

Even when more chlorpromazine was administered, neither a change in duration was observed nor a 'secondary discharge' elicited, but threshold voltage increased (Fig. 5). ( 3 ) Reserpine. Though reserpine, at a dose less than 0.1 mg/kg, had no effect on hippocampal after-discharge., a dose of 0.1 mg/kg of this drug did slightly increase the duration. Doses of 0.5-5 mg/kg of reserpine remarkably increased the duration of after-discharge, and subsequently produced the 'secondary discharge' (Fig. 1). ( 4 ) Chlordiuzepo.de. Doses of chlordiazepoxide, ranging from 1-1 0 mg/kg produced a slight prolongation in duration of the after-discharge, however, no 'secondary discharge' was observed and threshold remained unchanged. ( 5 ) Meprobumare. Administration of meprobamate in doses ranging from 5-50 mg/kg did not produce any change at all. (6) Imipramine. Imipramine, at a dose of 1 mg/kg, produced no change. On the other hand, doses of from 5-10 mg/kg of this drug increased duration and threshold. (7) LSD-25. LSD-25 (0.01-0.1 mg/kg), scarcely had any influence on duration of

ANALYSIS OF HIPPOCAMPAL AFTER-DISCHARGE

47

srt.6omin

w -

CORTEX

ES1V

wwm

L.AMYG

L AMYG

w -- .

C

R AMYG

rL1L_L1--.-_L*-lll\.I%%

--

CORTEX

W

W

R RF

l

W

L AMYG w

w

W

W

W

!

~

Pw

*

R AMYG

Fig. 5. Effect of chlorpromazine on hippocampal after-discharge. A = Control (before injection). Only the ‘primary discharge’ is observed; B-E = 60 min after injection of chlorpromazine 1 mg/ kg i.v. The ‘secondary discharge’ is shown following the ‘primary discharge’; C , D and E are 80, 100 and 220 sec after electrical stimulation respectively.

the hippocampal after-discharge. (8) Atropine. Atropine ranging from 0.5-2 mg/kg considerably increased duration (Fig. 6). (9) Scopolamine. Scopolamine had unstabilizing effects on hippocampal after-discharge, according to the doses of this drug (from 0.1-1.0 mg/kg); duration was remarkably decreased and increased. These phenomena appeared alternately during the course of time after the injection (Fig. 7). (10) Physostignzine. A dose of 0.1 mg/kg of physostigmine had scarcely any influence on the hippocampal after-discharge. After an administration of 0.5-1 .O mg/kg of this drug, the hippocampal arousal pattern was observed, and the duration of the after-discharge was remarkably prolonged. ( I I ) Acetylcholine. Acetylcholine was administered into the lateral ventricle by the References p . 52/53

48

c

T. I S H I K A W A et

al.

AM

--.

L AMYG

-

R AMYG

.

--.

.. . . -.

.,--

.

.

.

-.-

I

Fig. 6 . Effect of atropine on hippocampal after-discharge. A = control (bcfore injection); B = 45 min after injection of atropine 0.5 mg/kg i.v. Duration of after-discharge is remarkably prolonged. C - 93 min after injection. Complete recovery from the erect of atropine is observed.

previously mentioned method. At doses of from 0.25-0.5 pg/kg, duration of the hippocampal after-discharge was markedly increased (Fig. 8). CONCLUSION A N D SUMMARY

I. Hippocampal after-discharge consists of two phases: a 'primary discharge' and a 'secondary discharge'. In the 'primary discharge', the seizure discharge propagates to the opposite hippocampus, the fornix, the mammillary body, the anterior thalamic nuclei, the hypothalamic nuclei and the parieto-temporal and occipital regions of the neocortex. I n the 'secondary discharge', the seizure discharge propagates to the opposite hippocampus, the fornix, the maminillary body, the anterior thalamic and hypothalamic nuclei, the amygdala, the septum, the midbrain reticular formation and the diffuse areas of the neocortex (Gloor, 1955, 1957; Von Creutzfeldt, 1956; Green and Adey, 1956; Nauta, 1958), and is accompanied with some responses of the autonomic nervous system. These discharges are classified into 4 types as shown in Figs, 9 and 10.

ANALYSIS OF HIPPOCAMPAL AFTER-DISCHARGE

49

control

RF AM

A

-------

‘4

LAMYG

__u

R AMYG

- ---

-.. . l - - L ^ . P - - > &

RF

,-

Fig. 7. Effect of scopolamine on hippocampal after-discharge. A = control (before injection); B = 20 rnin after injection of scopolamine 0.1 rng/kg i.v. Duration of seizure discharge is shortened; 40 min after injection. Duration of seizure discharge is remarkably prolonged. C

11. The reticular activating system is not closely related to the hippocampal afterdischarge. ZII. The mode of action of psychotropic drugs is characterized by the absence of a depressing action on the hippocampal after-discharge. From this point of view, this mode of action is quite different from that of barbiturates (Table I) which produce marked depressing effects (Hirnwich, 1962). ZV.Chlorpromazine is an active adrenolytic and anti-serotonic agent. Reserpine is a catecholamine releaser. The concentration of acetylcholine in the brain increases by the administration of reserpine (Malhotra and Pundlik, 1959; Giarman and Pepeu, 1962; Malhotra and Das, 1962). It is probable that the cholinergic mechanism is closely related to the hippocampal after-discharge, as acetylcholine, chlorpromazine and reserpine facilitate the hippocampal after-discharge. It is assumed that the mechanism of this after-discharge is not simple, because both atropine and scopolamine can not depress it. No effect is shown on the hippocampal after-discharge by the administration of dopa or 5-hydroxytryptophan (Ishikawa, 1964); therefore, it is probable that the References p . 52/53

50

T. I S H I K A W A

et al.

CONTROL

aft 5 m i n

1 scc

CO$Ti7X+E2,L5!' RF__ B

- ...

AM. l4MYG

r AMYG

af t . 2 0 m i n

* -

-Il 0 O N lSCC

Fig. 8. Effect of acetylcholine on hippocampal after-discharge. A - Control (before injection); B = 5 min after injection of acetylcholine 0.25 pg/kg intraventricularly. Duration of after-discharge is markedly prolonged and a seizure pattern resembling the 'secondary discharge' is observed; C - 20 min after injection. The seizure discharge is completely recovered.

ANALYSIS OF HIPPOCAMPAL AFTER-DISCHARGE

51

change in catecholamine and serotonin in the brain is hardly related to the hippocampal after-discharge.

Fig. 9. Classification of hippocampal after-discharge associated with seizure patterns in amygdala, respectively. Height: amplitude of seizure. Length: duration of seizure. The first small line shows electrical stimulation. Narrow bar in Amyg shows slight changes in firing, but not active seizure discharge. Wide bar indicates remarkable seizure discharge.

Normal EEG rattern

E

-l=l

Cortex

-

Fig. 10. Scheme of hippocampal after-discharge. HPC = dorsal hippocampus; Amyg = amygdaloid nuclei (basolateral nuclei of amygdala); FX = fornix; MM = mammillary body; AM = anterior nuclei of thalamus; VPL = nucleus ventralis posterolateralis; SP = septum; RF = midbrain reticular formation; Cortex = neo-cortex (parieto-temporal area). Height of black square means magnitude of seizure discharge. References p. 52/53

r. I S H I K A W A et al.

52

TABLE 1 EFFECTS OF PSYCHOTROPIC D R U G S O N D U R A T I O N

OF H I P P O C A M P A L A F T E R - D I S C H A R G E ___.

~~

~

Hippocampal aferdischarge (control) ( )

'ose

Zlk)

Thiopcntal sodium Chiorpromazine

5-30 0.5-1 2-10 0.1 0.5-5 1-10 5-10 50 1

Reserpine Chlordiazepoxide Meprobamate Imipramine

5 10 ~_______ 0.01-0.1 0.5-2 ___-0.1-1 -or

LSD-25 Atropine Scopolamine

~

~

Physostygmine

0.1 __ 0.5-1 0.25-0.5

Acetylcholine

/"lb intravcntricular

* After-discharge is completely depressed. * * Secondary discharge is observed. REFERENCES ALLEN, N. F., (1941); Effect of ablating the pyriform-amygdaloid areas and hippocampi on positive and negative olfactory conditioned reflexes and on conditioned olfactory differentiation. Ainer. J . Physiol., 132, 81-92. FELDBERG, W., AND FLEISCHHAUER, K., (1963); The hippocampus as the site of origin of the seizure discharge produced by tubocurarine acting from the cerebral ventricles. J. Physiol., 168,435442, N. J., AND PEPEU, G., (1962); Drug-induced changes in brain acetylcholine. Brit. J . GIARMAN, Pharniacol., 19, 226-234. GIHHS,F. A,, AND GIBBS,E. L., (1936); The convulsion threshold of various parts of the cat's brain. Arch. Neurol. Psychiat., 35, 109-1 16. GLOOR,P., (1955); Electrophysiological studies on thc connections of the amygdaloid nucleus in the cat. Electroenceph. clin. Neurophysiol., I, 223-264. GLOOR,P., (1957); The pattern of conduction of amygdaloid seizure discharge. Arch. Neurol. Psychiat., 77,247-258. GREEN,J. D., AND ADEY,W. R., (1956); Electrophysiological studies of hippocampal connections and excitability. Electroenceph. elin. Neurophysiol., 8, 245-262. HIMWICH, H. E., ( I 962); Cited from special issue Tranquilizers, Barbiturates and the Brain, Galesburg, Galesburg State Hospital, Ill. ISHIKAWA, T., (1964); Unpublished data. W. T., AND AKERT,K., ( I 955); Hippocampal seizure states in guinea pig. Electroenceph. LIBERSON, elin. Neurophysiol., I, 21 1-222.

ANALYSIS OF HIPPOCAMPAL AFTER-DISCHARGE

53

MALHOTRA, C. L., AND DAS,P. K., (1962); Effect of reserpine on the acetylcholine content of the heart, the ileum and the hypothalamus of the dog. Brit. J. Pharmacol., 18, 190-193. MALHOTRA, C. L., AND PUNDLIK, P. G., (1959); The effect of reserpine on the acetylcholine content of different areas of the central nervous system of the dog. Brit. J . Pharmacol., 14,46-47. MORIN,F., AND GREEN, J. D., (1953); Diffuse after-discharges following stimulation of the fimbria hippocampi. Amer. J . Physiol., 175, 251-257. NAUTA,W. J. H., (1958); Hippocampal projections and related neural pathways to the mid-brain in the cat. Brain, 81, 319-340. SAWYER, C. H., EVERETT, J. W., AND GREEN, J. D., (1954); The rabbit diencephalon in stereotaxic coordinates. J . comp. Neurol., 101, 801-824. SWANN,H. G., (1934); The function of the brain in olfaction. J . comp. Neurol., 59, 175-201. VON CREUTZFELDT, O., (1 956); Die Krampfausbreitung im Temporallappen der Katze. Schweiz. Arch. Neurol. Psychiut., 77, 163-194.

54

Responsiveness of Cat Motor Cortex to Electrical Stimulation in Sleep and Wakefulness KITSUYA IWAMA

AND

TAKESHL KAWAMOTO

Departnient of Neurophysiology, Inytitute for Higher Nervoirs Activity, Osaka University Medical School, Osaka (Japan)

The purpose of this paper is to report on the responsiveness of the motor cortex to electrical stimulation in freely behaving cats. In various states of sleep and wakefulness observations were made of the following kinds of evoked activity, both central and peripheral : direct cortical response, cortical rhythmic after-discharges, pyramidal tract response and cortically-induced activity of the peripheral muscles. METHODS

Experiments were carried out on cats weighing 2.5 to 3.5 kg. According to the type of electrical activity to be studied, we implanted one or two of the following types of electrode into each animal: (I) For studies on direct cortical response and cortical rhythmic after-discharges, the tips of recording electrodes were put on the motor cortical surface about 5 mm apart. Stimulation was made with a pair of bipolar electrodes, the tips of which were implanted very close to one of the recording electrodes. (2) For studies on the pyramidal tract response, recording electrodes were of the bipolar type with tips about 1.5 mm apart. They were implanted stereotaxically with one of the tips in the pyramidal tract of the cerebral peduncle at the level of Frontal 5-7 of the Horsley-Clarke coordinates. To activate the corticospinal neurones at the cortical level, two electrodes, 3-5 mm apart, were implanted in the leg area of the motor cortex ipsilateral to the recording. (3) For studies on cortically-induced activity of the peripheral muscles, stimulating electrodes were similar to those for eliciting the pyramidal tract response. The recording was made from appropriate muscles of the hind legs with needle electrodes. These electrodes were inserted into the muscles as required. Besides the above-mentioned electrodes, all animals had permanent electrodes in the motor cortex and the dorsal hippocampus. These were used for monitoring spontaneous electrical activities. Since the motor cortex of one side was used for studying responsiveness to electrical stimulation, spontaneous electrical activity was monitored on the opposite side. Recording of the tonic activity of the neck muscles was useful for judging the depth of sleep, so this was done using needle electrodes nserted intramuscularly.

MOTOR CORTICAL RESPONSIVENESS I N SLEEP A N D W A K E F U L N E S S

55

The motor cortex was stimulated with an electronic stimulator having an independent control of the stimulus parameters. Except for activation of the peripheral muscles, the applied stimulus was a rectangular pulse of 0.05-0.5 msec duration and of variable intensity. Usually the stimulation was made every 1-2 sec. For inducing muscular activity, 3-5 brief pulses at 100/sec were applied to the motor cortex at a frequency of about 0.2/sec. All electrical activities were ampIified through C-R-coupled amplifiers and recorded with a cathode ray oscillograph or a pen-writer. In all experiments the sleep-wakefulness cycle was followed after putting the animal in an observation box (40 x 60 x 30 cm) with a glass window. A sound-proof room was not used. RESULTS

In the present experiment we distinguished three different states of sleep and wakefulness from behavioral and electrographic viewpoints. These were arousal, light sleep and deep sleep (Parmeggiani and Zanocco, 1963). The state of arousal is characterized by low voltage fast waves in the motor cortex, hypersynchronized slow waves (0-waves) in the dorsal hippocampus and high-amplitude, continuous discharges in the neck muscles. But the state which we refer to as arousal means that the cat is awake but shows no marked attentive attitudes towards his surroundings. During the state of light sleep the cat is sleeping and has high voltage slow waves and spindle discharges in the motor cortex, irregular waves in the dorsal hippocampus and maintained but reduced activity in the neck muscles. When sleep becomes deeper, the state of deep sleep develops in which the cat shows a central electrographic pattern similar to that seen in the state of arousal. As generally noted, however, no tonic activity can be recorded from the neck muscles in deep sleep. The electrographic characteristics of the three different states of sleep and wakefulness are seen in the pen-writer records in Figs. 2 and 3 . (1) Direct cortical response

The direct cortical response is a local electrical response of the cortex to direct surface stimulation. It is a surface-negative wave of long duration and is recordable only from the vicinity of the site of stimulation. Some authors consider that it originates from the apical dendrite of the cortex which is activated either directly or via synapses (Chang, 1951 ; Purpura and Grundfest, 1956). When following this type of evoked cortical activity during the sleep-wakefulness cycle, we noted that the cortical responsiveness was lower in arousal than in light sleep. A similar finding has been obtained by Purpura (1956) who showed that the direct cortical response in unanesthetized cats was greatly reduced when the EEG arousal reaction was evoked by stimulation of the brain stem. In addition, we found that the two types of sleep were distinguishable from each other by the magintudes of their responses to stimulation of a given intensity. These features are shown in Fig. 1. References p . 63

56

K . I W A M A A N D T. K A W A M O T O

10 msec

500,uV

Fig. I . Direct cortical responses in arousal (left), light sleep (middlc) and deep sleep (right). Continuous recording in each state. In all records thc initial triphasic deflections were shock-artifacts. In this and all subsequent records, the negativity of the picking-up electrode was recorded upwards.

In this experiment the applied stimulus was so weak that it did not elicit a discrete response when the cat was awake (left column). However, when light sleep developed, the previously ineffective stimulus became effective (middle column). A negative wave with a peak amplitude of more than 200 pV lasting for 30-50 msec resulted from each stimulus. This negative wave could be identified in all respects as a direct cortical response. The records in the right column of Fig. 1 were obtained when the cat was in the state of deep sleep. In this state it was possible to elicit a response as in light sleep, but its magnitude, either in amplitude or in duration, was smaller than in light sleep. The above results indicate that so far as the direct cortical response i s concerned, the responsiveness of the motor cortex is minimal in arousal, maximal in light sleep and intermediate in deep sleep. ( 2 ) Cortical rhythmic after-discharges

When the cortic.tl surface is stimulated with a rather strong shock, rhythmic afterdischarges usuallj follow the direct cortical response after an interval of several tens of msec. Such rhythmic after-discharges consist of surface-negative waves and closely resemble spontanec 11s spindle discharges and also the sensory after-discharges de-

MOTOR C O R T I C A L R E S P O N S I V E N E S S I N S L E E P A N D W A K E F U L N E S S

57

-

1 sec

Fig. 2. Ink-writer tracings of motor cortical EEG, hippocampal EEG and neck muscle EMG, shown from above downwards. Cortical surface stimulation was made to evoke rhythmic after-discharges every 2 sec. Left, arousal. Middle, light sleep. Right, deep sleep.

scribed by Chang (1950). It is known that both spontaneous spindle discharges and induced rhythmic after-discharges are well developed if the animal is lightly anesthetized with barbiuate. When the rhythmic after-discharges were examined in cats behaving freely, it was found that these could easily be produced while the cat was sleeping and they showed slow waves and spontaneous spindle discharges in the background EEG. This is shown in the middle record of Fig. 2. Upon precipitation of deep sleep. the cortical responsiveness for the rhythmic after-discharges was found to alter, as can be seen in the right records. In response to the same stimulus as in light sleep, the rhythmic afterdischarges appeared with reduced amplitudes and shorter durations. This may correspond to the fact that spontaneous spindle discharges are eliminated from the background EEG in deep sleep. In the other direction of sleep-wakefulness-transition it was seen that suppression of the rhythmic after-discharges became greater when the cat was wakeful (left record). In this condition the rhythmic after-discharges contained only a few waves with much smaller amplitudes than those shown in deep sleep. The afore-mentioned finding is obviously consistent with the result obtained by recording the direct cortical response: between the three states of sleep and wakefulness there is a gradation in the cortical responsiveness for producing the rhythmic after-discharges and the order of the responsiveness in the three states is exactly the same as for the direct cortical response. References p . 63

58

K. I W A M A A N D T. K A W A M O T O

( 3 ) Pyramidal tract response Thus far we have discussed the cortical responsiveness evaluated on the indices of direct cortical response and rhythmic after-discharges which are electrical activities recordable from the cortical surface. The index of cortical responsiveness, however, may also be sought in the efferent discharges of the cortical neurones. This is realized with the motor cortex by recording the evoked response from the pyramidal tract. The wave form of the pyramidal tract response to single shock stimulation of the motor wtex was first described by Patton and Amassian (1954) who recorded the response from the medullary p4ramid. We recorded the pyramidal tract response from the cerebral peduncle and found that its wave form was virtually the same as that described by the above authors. Our recording shows that the peduncular pyramidal tract response appears with a latency of 0.2-0.3 msec and has 3-4 consecutive waves of positive polarity.

-

1 sec

200pv

Irnsec

1OOpV

Fig. 3. Pyramidal tract responses in arousal (A), light sleep (B) and deep sleep (C). Motor cortical EEG, hippocampal EEG and neck muscle EMG were shown from above downwards. Dots above the motor cortical EEG record are marks of cortical stimulation to cvoke the pyramidal tract responses which were superimposed and gave the record on the right.

MOTOR C O R T I C A L R E S P O N S I V E N E S S I N S L E E P A N D W A K E F U L N E S S

59

Sample records of the pyramidal tract response during the sleep-wakefulness cycle are shown in Fig. 3. Records A, B and C were obtained in arousal, light sleep and deep sleep, respectively. On the right of the figure the pyramidal tract responses are reproduced which were obtained by superimposing 10 faint traces during the corresponding ink-writer records. The differences in the potential pattern of the three pyramidal tract responses are quite distinct: only two waves were evoked in arousal, whereas the record in light sleep contained one or two additional waves. The response in deep sleep had three waves unlike that in arousal, but the third of these was maller than the corresponding one in light sleep. There is another notable finding. In the pyramidal record in light sleep, superposition of many faint traces resulted in displaying the response with a rather thick line, suggesting that there was some fluctuation in the responsiveness of the impulse origin. This fluctuation in the responsiveness was reduced in deep sleep and was minimal in arousal. Zanchetti and Brookhart (1958) have proposed that the area of the pyramidal tract response (volts x time) can be taken as an index of the corticospinal responsiveness. If this is accepted, our records show that the corticospinal responsiveness is modified during the sleep-wakefulness cycle in about the same way as the electrical responses of the cortical surface.

10 rnsec

1 mV

Fig. 4. Cortically-induced activity of the flexor muscles of the hind leg in arousal (left), light sleep (middle) and deep sleep (right). Recording was continuous in each state. Dots below each sweep are marks of the cortical stimulus, References p.163

60

K. I W A M A A N D T. K A W A M O T O

( 4 ) Cortically induced activity of the peripheral muscles

Tn the experiment of Fig. 4 recordings were made from the flexor muscles of the hind leg using 3 pulses at 100/sec for cortical stimulation. The stimulus was made as strong as possible insofar as it did not wake the sleeping cat. While the cat was awake, the muscles responded to the cortical stimulus with large potentials of short duration without showing long-sustained tonic discharges. This is seen in the records of the left column. This response pattern was maintained when the cat entered light sleep, though there was a tendency for the muscular potential to increase slightly (middle column). On the other hand, the situation in deep sleep was entirely different from those in arousal and light sleep (right column). Thus it was seen that a cortical stimulus which was effective in arousal and light sleep ceased to elicit a muscular response as soon as deep sleep precipitated, though sizable responses appeared very occasionally. That the peripheral muscular response is virtually absent in deep sleep could be ascertained by using a long train of pulses, for example, 50/sec pulses lasting 2 sec, for the cortical stimulation. We have shown that there is a difference in the cortical responsiveness in the two types of sleep so far as the cortical surface responses and the pyramidal tract response are concerned. This difference is definite, as we have demonstrated, but it is very slight. Therefore, it seems unlikely that the distinct difference in the peripheral muscular response in the two types of sleep could be explained as due entirely to the difference in the responsiveness at the cortical level. It must be supposed that some neural structures, lying in the downstream of the motor cortex and contributing to the cortical induction of the peripheral muscular response, change drastically in function when sleep changes from one type to another.

DISCUSSION

First, the pyramidal tract response and the cortically induced activity of the peripheral muscles, and then the implication of the present observation on the cortical surface responses will be discussed. Using cats with a mesencephalic coagulation, Zanchetti and Brookhart ( I 958) attempted to correlate the corticospinal responsiveness with the background EEG activity of the motor cortex. They reported that the corticospinal responsiveness fluctuated when spontaneous spindle discharges were occurring in the background EEG, and the fluctuation was reduced during lulls of spindle discharges or when low voltage fast waves were induced by activating stimulation applied either centrally or peripherally. They pointed out, however, that in the central tendency of the responsiveness no significant differences could be found between the three conditions of the background EEG. Our experiments on the pyramidal tract response are essentially the same as those performed by the above authors, except that we used freely behaving cats. In agreement with these authors we found that fluctuation of the corticospinal responsiveness was considerable when the cat was sleeping and showing spontaneous spindle dis-

MOTOR C O R T I C A L R E S P O N S I V E N E S S I N S L E E P A N D W A K E F U L N E S S

61

charges in the motor cortex and that the fluctuation was reduced when low voltage fast waves appeared as a result of spontaneous awakening or precipitation of deep sleep. We noted, however, that the pyramidal tract response during light sleep was greater than that when low voltage fast waves were present, irrespective of whether the latter were associated with arousal or deep sleep. This is inconsistent with the findings ofzanchetti and Brookhart. This discrepancy may be due to the difference in the condition of the experimental animals. Arduini and his coworkers (1963) recorded the activity of the pyramidal tract in freely behaving cats in various states of sleep and wakefulness. However, these authors concentrated their attention on spontaneous activity, whereas we were concerned with evoked activity. They reported that the spontaneous pyramidal tract activity which was steady during arousal was decreased in light sleep, and that upon precipitation of deep sleep it increased to or exceeded the value in arousal. These results are inconsistent with our findings that the evoked pyramidal tract activity was greatest in light sleep, least in arousal and intermediate in deep sleep. It might be said that the responsiveness to stimulation is not directly comparable with the tendency to show the spontaneous activity. Virtually complete absence of tonic activity in the peripheral muscles has been reported as one of the characteristics of deep sleep (Dement, 1958; Jouvet, 1961; Rossi et al., 1961 ; Parmeggiani and Zanocco, 1963). Moreover, recent studies have shown that the spinal reflex activity of the muscles is abolished or greatly reduced in deep sleep (Giaquinto el a!., 1964a, b). In addition, we have found that abolition of muscular activity in deep sleep is also observed on activation by motor cortical stimulation. It seems most probable that there may be a common neural mechanism involved in these phenomena. One of the most interesting findings in the present experiments is that the functional state of the motor cortex in deep sleep cannot be considered to be the same as that in arousal, though the spontaneous EEG activities in both states are equally characterized by low voltage fast waves. Comparing the cortical surface responses and the pyramidal tract activity of the three different states of sleep and wakefulness, we have established that the functional state of the motor cortex in deep sleep is intermediate between those in arousal and light sleep. Since it is generally accepted that the two states, arousal and light sleep, are distinguished from each other by the strength of activation, it is suggested that deep sleep has an intermediate position between arousal and light sleep with regard to the strength of activation. In other words, deep sleep which has been referred to as ‘activated sleep’ is a less activated state than arousal. The above-mentioned view led us to suppose that on close examination the patterns of the spontaneous EEG of the motor cortex in arousal and deep sleep might be found to differ, reflecting the difference in thc strength of activation. In collaboration with us, Dr. S. Kiyono approached this problem by the method of frequency analysis of the EEG. He sampled the continuous EEG records of more than 1 min and analyzed them with an automatic frequency analyzer. This analyzer was provided with 23 band-pass filters to cover the frequency range from 1 to 60 cjsec. The output References p.-63

62

K. I W A M A A N D T. K A W A M O T O

from each filter, integrated for every 10 sec, was measured in arbitrary units, and the average and standard deviation were calculated. An example of the results is illustrated in Fig. 5. The spectral difference in the EEG in arousal and light sleep is seen to be most marked at frequencies below 16 cjsec. This is interpreted as showing that activation, which brings the cat from light sleep to arousal, results in reduction of the EEG components in this frequency range. From the same point of view the activation operating in deep sleep can be said to be less strong than that in arousal, because the EEG spectrum in deep sleep is displaced from that in arousal towards the level in light sleep, although the two spectra are very similar to each other. The EEG spectral difference between arousal and deep sleep is most marked at frequencies below 16 cjsec. I

- - - - -.. Light

sleep

-D e e p s l e e p Arousal

Fig. 5. EEG spectra of the motor cortex in arousal, light sleep and deep sleep. Ordinates, average amplitudes in arbitrary units. The average was taken over 10 consecutive blocks of the 10-sec intcgration epoch. Abscissae, frequencies in c/sec with divisions according to the width of the tuning frequencies of filters. The spectra of deep sleep and arousal were plotted with slight shifts on the abscissa1 axis from their correct positions.

The direct cortical response has been believed to originate in the structure responsible for spontaneous slow wave activity of the EEG such as spindle discharges (Tasaki et al., 1954; Clare and Bishop, 1955; Purpura and Grundfest, 1956). It is also reasonably supposed that the cortical rhythmic after-discharges and spontaneous spindle discharges have a common generating mechanism, because the two types of activity behave in much the same way under various physiological conditions. With regard to these cortical surface responses, we have shown that the responsiveness of the motor cortex is higher in deep sleep than in arousal. This is in good accord with the view that the mechanism for generating slow wave activity of the EEG is more active in deep sleep than in arousal, as suggested by the frequency analysis. SUMMARY

(1) The responsiveness of the motor cortex to electrical stimulation was studied during the sleep-wakefulness cycle of freely behaving cats carrying permanently im-

MOTOR CORTICAL RESPONSIVENESS I N SLEEP A N D W A K E F U L N E S S

63

planted electrodes. From behavioral and electrographic viewpoints, three states, namely arousal, light and deep sleep, were distinguished. (2) The direct cortical response, produced by stimulation of the cortical surface and recorded from the vicinity of the site of stimulation, appeared in light sleep with a higher amplitude and a longer duration than in deep sleep, and was difficult to obtain in arousal. (3) The cortical rhythmic after-discharges were observed by applying a strong stimulus to the cortical surface. The response was greatest in light sleep and took on a configuration similar to that of spontaneous spindle discharges. It was reduced in deep sleep and was smallest in arousal. (4)The efferent discharges of the corticospinal neurones, elicited by single shock stimulation of the motor cortex and recorded from the pyramidal tract of the cerebral peduncle, were largest in light sleep, least in arousal and intermediate in deep sleep. (5) Whereas motor cortical stimulation could activate the peripheral muscles in arousal and light sleep, it failed to do so in deep sleep. (6) It was concluded that activation operating in deep sleep is intermediate in strength between those during arousal and light sleep. This view was supported by frequency analysis of the spontaneous EEG activity of the motor cortex. REFERENCES ARDUINI, A,, BERLUCCHI, G., AND STRATA. P., (1963); Pyramidal activity during sleep and wakefulness. Arch. ital. Biol., 101, 530-544. CHANG,H.-T., (1950); The repetitive discharges of corticothalamic reverberating circuit. J . Neurophysiol., 13, 235-257. CHANG, H.-T., (1951); Dendritic potentials of cortical neurones produced by direct electrical stimulation of the cerebral cortex. J . Neurophysiol., 14, 1-21. M. H., AND BISHOP,G. H., (1955); Properties of dendrites: apical dendrites of the cat cortex. CLARE, Electroenceph. elin. Neurophysiol., 7, 85-98. DEMENT, W., (1958); The occurrence of low voltage, fast, electroencephalogram patterns during behavioral sleep in the cat. Electroenceph. clin. Neurophysiol., 10, 291-296. S., POMPEIANO, O., AND SOMOGYI, I., (1964a); Supraspinal modulation of heteronymous GIAQUINTO, monosynaptic and of polysynaptic reflexes during sleep and wakefulness. Arch. ital. Biol., 102, 245-28 1. GIAQUINTO, S., POMPEIANO, O., AND SOMOGYI, I., (1964b); Descending inhibitory influences on spinal reflexes during natural sleep. Arch. iful. Biol., 102, 282-307. JOUVET,M., (1961); Telencephalic and rhombencephalic sleep in the cat. Ciba Synip. Nature of Sleep. G. E. W. Wolstenholme and M. O'Connor, Editors. London, Churchill (p. 188). PARMEGGIANI, P. L., AND ZANOCCO, G., (1963); A study on the bioelectrical rhythms of cortical and subcortical structures during activated sleep. Arch. iful. Biof., 101, 385-41 2. V. E., (1954); Single- and multi-unit analysis of cortical stage of PATTON,H. D., AND AMASSIAN, pyramidal tract activation. J. Neurophysiol., 17, 345-363. PURPURA, D. P., (1956); Observation on the cortical mechanism of EEG activation accompanying behavioral arousal. Science, 123, 804. D. P., AND GRUNDFEST, H., (1956); Nature of dendritic potentials and synaptic mechaPURPURA, nisms in cerebral cortex of cat. J . Neurophysiol., 19, 573-595. E., HARA,T., GIUSSANI, A., AND Succo, G., (1961); Researches on the nervous R o w , G. F., FAVALE, mechanism underlying deep sleep in the cat. Arch. ital. Biol., 99, 270-292. I., POLLEY, E. H., AND ORREGO, F., (1954); Action potentials from individual elements in TASAKI, cat geniculate and striate cortex. J . Neurophysiol., 17, 454474. J.'M., (1958); Cortico-spinal responsiveness during EEG arousal ZANCHETTI, A., AND BROOKHART, in the cat. Amer. J . Physiol., 195,262-266.

64

Epidemiological and Clinicopathological Study on Cerebrovascular Disease in Japan SHIBANOSU K E K ATSUKI Department of Internal Medicine and Neurological Institute, Facnlty of Medicine, Kyushu University, Fukuoka (Japan)

I. EPIDEMIOLOGICAL ASPECTS

It has been generally assumed that in western countries the incidence of death attributable to heart diseases (H D) is higher than that to cerebrovascular diseases (CVD). Statistical data in Japan, however, have been shown to suggest the reverse. If it be true, this will be an intereqting subject of study requiring intensive investigation because atherosclerotic changes are known to be much less advanced in the Japanese population. Our clinicopathological studies confirm that a mean severity of cerebral atherosclerosis of the Japanese population is lower than that of the American living on the mainland. Imai et al. (1960) and Tamari (1962) clearly demonstrated that the degree of atherosclerotic changes in the aorta as well as in the coronary artery was over 20 years more advanced in the American than that in the Japanese of West Japan. These studies were carried out according to the criteria proposed by Gore and Tejada (1957). The findings may support the well-known clinical evidence of more frequent coronary heart disease in the United States. Moreover, our co-workers, Okabe et al., confirm the same trend with cerebral atherosclerosis. Goldberg and Kurland (1962) reported that death due to CVD in Japan was the highest among those in 33 countries, and it was mainly due to an exceedingly high incidence of cerebral hemorrhage. The annual death rate from cerebral hemorrhage was about 180 in Japan, about 65 in the United States, and about 20 in Mexico per 100,000 of population. However, these statistics were mainly based upon death certificates, and the cause of death was not necessarily confirmed by post-mortem examinations. Most of the studies conducted not only in Japan but also in the other countries were based on hospital records or death certificates. However, hospital records may not represed an actual incidence of the disease, since admissions to hospitals are selected by the nature of diseases and also by socioeconomic conditions. Furthermore, reliability of death certificates in determining the cause of death is not certain unless post-mortem examinations are performed, particularly in those cases which terminate in a relatively short period after the initiating diseases such as CVD or HD. According to the Japanese vital statistics in 1960, death from CVD was 20.7%

65

C E R E B R O V A S C U L A R DISEASE I N J A P A N

20.: "lo

C.V.D.

Malignancy Heart disease Seni11ty Pneumonia Accident Tuberculosis Gastroenter itis Suicide Neonatal disease

Fig. 1 . Main causes of death among Japanese (Japanese Vital Statistics, 1960).

which was the highest, malignancies 13.2% and HD ranked third, which was 9.1 % of the total deaths (Fig. 1). When the death rate due to CVD was considered in relation to age, the death ratio of CVD to all the deaths was 15 % in the 5th decade which gradually increased with age up to 31 % in the 7th decade and then slightly decreased. However, the annual death rate of CVD per 100,000 of population always increased, from 64 in the 5th decade to 3419 in the group aged over 80 (Fig. 2). Furthermore, Annual death

No of death Age

due to C V D

Death ratio

of C V D

rate per 100,COO

Fig. 2. Deaths from CVD in Japan (Japanese Vital Statistics, 1960). References p . 88/89

66

S. K A T S U K I

total deaths and the death rate of CVD have been increasing since the Second World War. The death rate due to CVD was about 24% in 1963 which almost doubled that of about 12% in 1950. This may be partly because of the current increase in the elderly, and shows that CVD has become more important in the management of our health problem in Japan. With regard to the population survey on CVD in Japan, the previous investigators showed that the prevalence of CVD ranged from 275 to 910 per 100,000 population and was higher in the northern part of Japan. However, the backgrounds of these studies were not standardized and may not be suitable for comparative analysis. We have recently assembled a research team on CVD sponsored by the Ministry of Education of Japan, in which 14 main university hospitals participate. The study has been in progress in order to elucidate the incidence of CVD. The subjects aged over 40 numbered 21,800, among which 443 died during the first year from August 1962 to July 1963. Deaths due to CVD were 163, which was 34.5% of all the deaths. Among the death cases diagnosis was made by autopsy in 21, examination by members of the team in 29, and by information either from local physicians or from families in 393. In the following, our own study will be described, because it is most advanced (Kabuki, Hirota ei al., 1964a). We chose Hisayama-town located near Fukuoka City in Kyushu Island. The geographical characteristics of this town are shown in Fig. 3. The whole population

FUKUOKA

PACIFIC

Population 6521 ( 1960 census) 1841 (over the age of 4 0 ) 27.6 ' l o Whole Japan 28.0% .Occupation Farming 5 4 % Mining 2 2 "lo 0

Fig. 3. Location and population of Hisayama.

CEREBROVASCULAR DISEASE IN J A P A N

67

was 6521 according to the census in 1960. The study was started in the spring of 1961. The reasons we chose this community were that this town is close to our institution, about 10 miles from the University Hospitals, the size of the population was considered to be adequate for our detailed prospective study, the annual variation of the whole population had been shown to be small and the representatives and three medical practitioners of the town were co-operative for the study. This small town is also typical of rural areas in Japan. For the first part of the study, cross-sectional examinations were performed on the residents of both sexes aged over 40, collected by the original resident registration list of the town. The examinations were completed in 1658 out of a total of 1841 subjects (90.1 %). They were on the following items: body height, body weight, urinalysis, electrocardiogram, ocular fundi, serum total cholesterol and physical examinations. Besides these, present complaints, past medical history, family history and socioeconomic status of each subject were recorded at the time of registration. Neurological examinations revealed 25 cases with CVD with manifestations of hemiplegia and other symptoms. Therefore, the prevalence rate of CVD in this community was roughly estimated 383 per 100,000 population, since, CVD rarely occurred in those under 40. There were 5 cases with old myocardial infarction, and the prevalence of this disease was 77 per 100,000 population. The results were as follows: 430 out of 1658 (29.6%) had elevated blood pressure, systolic over 160 mm Hg and/or diastolic over 95 mm Hg according to WHO criteria (1959); 21.3% were in borderline hypertension; retinopathy as graded KW I1 or more was found in 22.8 %; abnormal ECG findings according to Minnesota Code in 56.4%; proteinuria in 6.5 %; glycosuria in 4.9%; and hypercholesterolemia (over 186 mg/100 ml) in 31.1 %. The prospective study has been followed since November 1961 when the first examinations were completed. The number of subjects in this study was 1621 which was slightly less than that at the time of the cross-sectional study, because the following were excluded: 4 died, 8 moved out of the town during the time of cross-sectional study and 25 already had manifestations of CVD as described previously. During the period of two years until October 1963 CVD developed in 28 cases. Therefore, the annual incidence rate of CVD was approx. 2 15 per 100,000population in this community, which is believed to be the first value based on a pcpulation survey in Japan. As previously mentioned, in order to determine the efficacy of this kind of study, it was essential to study in detail the entire population and to follow it as completely as possible. With this in mind, at the beginning of this study, most of our efforts were directed towards obtaining co-operation of the three medical practitioners and of all the residents in this town. The members of our own research group visited the town at least twice a week in order to keep contacts with the practitioners and with representatives of the two central town offices. Whenever acute illness or any accidents occurred among the subjects, one of us on duty was asked to join in the consultation, so that practically all the cases described in this report were examined by ourselves or their case histories carefully reviewed. Some of them were brought to our University Hospitals by ambulance for treatment and further examination. Since the main purpose of this study at the beginning was to establish an actual death ratio of CVD to Refcrcnces p 88/89

68

S. K A T S U K I

HD in this population, much effort was made to determine the cause of death by post-mortem examinations. Although the autopsy cases were few at the beginning of this study, they gradually increased, and over 80 % of all the death cases underwent autopsy during the period from January to October 1963. The most noteworthy finding was considered to be the cause of death in autopsied as well as in non-autopsied cases. There were 58 deaths in the two years. Of these the cause of death was verified by post-mortem examination in 22 cases (37.9 %) and in the rest it was determined on a clinical basis. Cause of death thus determined was as follows: CVD 15, among which cerebral hemorrhage 7, cerebral thrombosis 2, cerebral embolism 1, subarachnoid hemorrhage 2 and type undetermined 3; heart disease 10; malignancies 9; miscellaneous such as liver disease and pneumonia etc. 20; and unclassified 4 (Table 1). TABLE I CAUSE OF DEATH

Hisayama, Subjects: 1621 (over the age of 40), Nov. 1961-Oct. 1963. Cause of death

No.

Autopsied

CVD Cerebral hemorrhage Cerebral thrombosis Cerebral embolism Subarachnoid hemorrh. Hemorrhage? Infarction?

15 7 2

8

Heart disease Malignancy Miscellaneous CVD? Heart? Others?

10

1

2 3

4

1 1 2 0

9 20

1 5 8

4

0

-

Total

58

22 37.9 %

As for the age effect, CVD was more common in the old age group: for instance, it

occurred in 8 out of 1037 (0.8 %) below the age of 60 and in 20 out of 584 (3.4 %) over the age of 60 (Table 11). This was particularly true in cerebral infarction, but cerebral hemorrhage more commonly occurred below the age of 60. Regarding high blood pressure as a risk of developing CVD, from the group of normal blood pressure, cerebral infarction occurred in 2 cases but none in cerebral hemorrhage. From the group of borderline hypertension, cerebral infarction developed in 3 cases including one with embolism, but none in hemorrhage. From the group of hypertension, there were 9 cases with cerebral hemorrhage and 6 with cerebral infarction. The subjects with elevated blood pressure were more prone to the development of CVD and this was particularly true with cerebral hemorrhage (Table 111). The precipitating factors of CVD were analyzed in these 28 cases, although they are not conclusive as yet. The following appeared to be significant: age over 60,

69

CEREBROVASCULAR DISEASE I N JAPAN

T A B L E I1 Two

C V D A C C O R D I N G TO Hisayarna, Nov. 1961-Oct. 1963.

YEAR INCIDENCE OF

c VD

No. of subjects

40-49 50-59

564 473

60-69 70-79 80-89 90

364 I68 47 5

Total

I621

*P

:<

A G E AT E N T R Y

%

No.

10 7

[

0.8*

1

3.4*

3 f

0 28

~

1.7

0.001 T A B L E 111

HYPERTENSION A N D CVD Hisayama, Nov. 1961-Oct. 1963.

Blood pressure ( W H O criteria)

Hypertension*** * Borderline hypertension* * Normotension*

Hemorrhage

410

9

6

1

3

344 867

0 0

3 2

1 0

I 2 6

1621

Infarction

Subarach. Hemorrhage? ? hemorrhage

-

~

Total

C VD

__

No. of subjects

9

11

2

Total

19*.** 5** 4* 28

* P < 0.001 ** P = 0.021 heredity of CVD, neurological signs such as headache, dizziness and numbness of the extremities, abnormal ECG such as high amplitude R in the left leads or ST depression and retinopathy more than KW 1. Other factors such as sex, occupation, alcohol intake, smoking habit, body weight, serum total cholesterol level, urinary findings for protein and sugar did not seem much to affect the evolution of the disease (Table IV). Incidence of CVD according to serum total cholesterol level at entry is shown in Table V. In summary, an outline of the recent studies on epidemiological aspects of CVD in Japan has been briefly reviewed. My feeling from these studies is that frequency of CVD exceeds that of HD as far as death from these diseases is concerned, and cerebral hemorrhage seems more common than cerebral infarction. Since our study of Hisayama References p . 88/89

70

S. K A T S U K I

T A B L E IV P R E C I P I T A T I N G FAC’TOKS I N C V D From prospective study in Hisayama, Nov. 1961-Oct. 1963.

Precipitating fuctor

I. 2. 3. 4. 5. 6.

Over the age of 60 Family history of CVD Complaints (headache, dizziness, numbness) Hypertension (WHO criteria) EKG (high amplitude R in left, ST depression) Retinopathy (KWT4V)

Sex, occupation, alcohol intake, smoking, weight, cholesterol, proteinuria, glycosuria

1 \

P P P

0.001 0.017 0.004 P -: 0.001 P < 0.001

P

c .

= ~

=

0.015

not signiticant

TABLE V I N C I D E N C F OF

CVD

A C C O R D I N G T O SERUM TOTAL CHOLESTEKOL I F V L L AT ENTRY

Hisayanla, Nov. 1961LApr. 1964. -

Cholerterol level* (rwgllO0 nil)

over 300 250-299 200-249 150-199 100-149 50-99 Unexarnined Total :::

C‘ VD

No. of Jubjects

No.

2 30 I50 652 668 68 51

0 0 6 17 8 I 2

__

-

1621

34

o/

/o

4.0** 2.6** 1.2** 1.4** 3.9 2.1

Zak-Henly method P < 0.20

* * 0.10

is still in progress and the autopsy rate has curreittly greatly increased, more detailed analysis could be made in the near future. Meteorological observations, such as those of temperature, humidity and atmospheric pressure, have been started this year because of the impression that cerebral vascular accidents more frequently occurred in winter in this working population of Hisayama. A nutritional survey is also to be added. 11. P R E D I S P O S I N G F A C T O R S I N

CVD

(FOCAL V U L N E R A B I L I T Y OF THE B R A I N

TISSUE I N D E V E L O P M E N T OF CEREBROVASCULAR DISEASE)

It is well established that hemorrhagic lesions as well as cerebral infarction are most frequently seen in particular areas of the brain. According to our study utilizing 50

71

C E R E B R O V A S C U L A R DISEASE I N J A P A N

cases with hypertensive cerebral hemorrhage and 49 cases with encephalomalacia, both the lesions were most frequently seen in the cerebrum, the region of the basal ganglia, particularly of the putamen being most frequently affected. In the pons, the areas of the paramedian arteries were predisposed to the lesions (Akazome, 1964). These findings cannot be simply attributed to atherosclerotic changes. Other factors such as those relating to hemodynamics and to metabolic vulnerability of the particular areas of the brain tissue must be involved in the development of these lesions.

( I ) Cerebral atherosclerosis and C VD The degree of atherosclerotic changes in the arteries at the base of the brain was evaluated according to the criteria of Gore and Tejada (Table VI). These criteria are based 011 the nature of degenerating changes of the arterial wall and the extent of the lesions. In 157 autopsy cases aged over 40, the atherosclerotic changes were far more advanced in cerebral hemorrhage and infarction. N o marked difference in Broca’s index was found between CVD and the other diseases. The degree of cardiac hyperT A B L E VI A T H E R O S C L E R O T I C CHANGES AT THE BASE O F THE B R A I N I N V A R I O U S DISEASES

Total of I57 cases, age over 40.

Cerebral hemorrhage Cerebral infarction Stomach cancer Lung cancer Other malignancies Pu1m onary tuberculosis Others

No. of cases

Age, average

Broca index*

Cardiac hypertrophy

Atherosclerotic index

12

58.6

0.83

2.86

63.7

5

70.4

0.77

2.78

76.8

22 9 61 6

57.4 57.0 56.4 55.0

0.70 0.76 0.73 0.63

1.46 1.69 1.64 1.54

8.2 2.2 17.5 6.5

42

56.6

0.77

2.00

15.7 -

*

Broca’s index

=

body weight in kg (body length in cm

-

100).

trophy indicative of pre-existent hypertension was significantly increased in both cerebral hemorrhage and infarction. These results indicated that CVD was closely related to atherosclerosis at the base of the brain and to cardiac hypertrophy, but could not explain the view that certain areas of the brain tissue are predisposed to CVD. When the atherosclerotic index was compared among arteries at the base of the brain, it was much higher in cases with CVD than in those without CVD. This was true with the internal carotid artery, the anterior, middle and posterior cerebral artery, and the basilar and vertebral artery. With the exception of the anterior artery, in which the index was lowest, no marked difference in the indices was found among the arteries above mentioned in cases with cerebral hemorrhage. In cerebral infarction, Reference3 p . 88/89

72

S. K A T S U K I

Cerebral hemorrtege 12 cases Cerebral infarction

D m

5 cases

m 10.

u

m

Fig. 4. Atherosclerotic index (Gore and Tejada).

the average index was exceedingly high in the middle cerebral artery, because the study included the two cases with complete occlusion; however, the same trend was also noted otherwise (Fig. 4). When the degree of atherosclerotic changes in the middle cerebral artery was considered in relation to the site of the lesions, there was no marked difference between the affected and non-affected sides in cases with hemorrhage in the region of the basal ganglia; however, it was more marked on the affected side than on the opposite in cases with cerebral infarction in the same region. No difference in the index in the two hemispheres was found in cases without CVD. These results indicate that the development of cerebral infarction in the region of the T A B L E VI1 ATHEROSCLEROTIC l N D l C E S Ob THE MIDDLE CEREBRAL ARTERY

Hemorrhage in the region of the basal ganglia Infarction in the same region Non-CVD

No. of cases

Affected side

Non-affected side

19

1.9

1.6

13

14.8

1.3

185

1 .o

1 .o

C E R E B R O V A S C U L A R D I S E A S E IN J A P A N

73

basal ganglia is closely related to the atherosclerotic changes in the middle cerebral artery (Table VIl). An atherosclerotic plaque was also frequently noted in the extracerebral portion of the striate arteries on the affected side of cerebral infarction

Fig. 5. Plaque in the striate artery.

(Fig. 5), but it was much less frequent in the non-affected side of the infarction, and in cases with cerebral hemorrhage. This finding suggests that the atherosclerotic changes in the extra-cerebral portion of the striate arteries are also related to pathogenesis of cerebral infarction. ( 2 ) Aizqioarchitectural aspects As previously stated, the most important artery to perfuse the area of the basal ganglia is the striate artery which branches off the middle cerebral artery. The lateral branchings of these arteries irrigate the putamen, the external capsule, the body of the caudate nucleus and the upper part of the internal capsule, one of which has been called ‘Arthre de l’hemorrhagie cCrCbrale’ by Charcot. The medial branchings of these arteries perfuse the globus pallidus and a part of the internal capsule. The recurrent arterv of Heubner branching from the anterior cerebral artery is responsible for the perfusion of the head of the caudate nucleus and the putamen, the anterior portion of the globus pallidus, the anterior half and the knee of the internal capsule. The thalamus is perfused by the thalamo-perforating arteries, branches of the posterior cerebral artery. The medial portion of the brain stem is nourished by the References p . 88189

74

S. K A T S U K I

paramedian arteries branching from the basilar artery and the outer portions by Aa. circumferentes breves and longes. During several years we have made observations in detail on the angioarchitecture of the brain arteries, particularly of those above mentioned, by making cast models (Katsuki et al., 1963a). The cerebral vascular cast is made by injecting special acrylic material into the cerebral vessels and dissolving the brain substance proper with sodium hydroxide. Fig. 6 illustrates the medial view of a cast in normal cerebral

Fig. 6. Medial view of the normal cerebral arteries.

arteries. A close-up view of the striate arteries is shown in Fig. 7. As shown in the schematic illustration, blood flow through the middle cerebral artery is towards the right as indicated by an arrow, and the flow in the striate arteries is in the opposite direction. The recurrent artery of Heubner also branches in this fashion from the anterior cerebral artery and this type of ramification is occasionally seen in the thalamoperforating artery (Tomonaga, 196 I). As regards the basilar artery, the anterior cerebellar artery often ramifies at right angles from the basilar artery, and the anterior inferior cerebellar artery ramifies sometimes in retrograde fashion, although there are many variations in the latter. The paramedian arteries and the Aa. circumferentes breves often branch in retrograde fashion from the caudal portion of the basilar artery, but less frequently from the oral portion of the artery. Frequencies of this type of ramification in various cerebral arteries are summarized in Fig. 8. Retrograde ramification was common in the striate arteries (96 %), in the recurrent artery of Heubner (88%) and in the orbital arteries (77%). The paramedian arteries at the caudal portion of the brain stem were found to be branching off in this fashionin 59 %.

75

CEREBROVASCULAR DISEASE I N J A P A N

Striate crteries

I

Middle cerebral artery Fig. 7. Retrograde ramification of the middle cerebral artery.

/a

0

C>.-trarr

i arwr es

r r c - r i cnl

ar':er es

str a c

40

20

60

w t c - cs

80

100

96

I naiarnoperfor31 ale:- es Ant

cncruc. J K C ' (J',

Perforating branches post. cornrn. arteries Pararnedian a r t e r i e s ( lrom oral ) Pararnedian arteries (caudal

c

25

Fig. 8. Frequency of retrograde ramification.

The retrograde ramification was not common in the other arteries such as those of the thalamo-perforating, the anterior choroidal, the perforating branches of the posterior communicating arteries and the paramedian arteries at the oral portion of Rrferrnces p 88/89

76

S. K A T S U K I

the brain stem. It is interesting to note that this type of ramification is often found in the areas predisposed to vascular lesions. Although the significance of the angioarchitectural characteristic in the pathogenesis of CVD still remains for further investigation, the vulnerability of these particular areas of the brain is thought to be related to this structural characteristic, particularly in elderly atherosclerotic or hypertensive individuals. Retrograde ramification of the striate arteries was first described by Shellshear (1921). Kristenson (1947) considered that this type of ramification is an embryonic product because of the strong development of the hemispheres laterally, whereas the central ganglia remain in their original places. Through this development the origin of the vessels will be displaced laterally opposite to the blood stream. This type of ramification is usually seen at the places where the small arteries branch off directly from the large stems; this can be considered to be a physiological device to protect these branches against an acute rise in blood pressure. However, it is probable that this type of structure can accentuate the circulatory disturbances

Fig. 9. Node formations in the small cerebral arteries.

CEREBROVASCULAR DISEASE IN J A P A N

77

in pathological states. The absence of collateral anastomosis of these branches may also contribute to the development of the lesions. With regard to the abnormalities of the circle of Willis in the development of CVD, it was reported (Kameyama, 1961), that the incidence of cerebral hemorrhage and cerebral infarction was higher in cases with marked difference in size between the two sides of the anterior cerebral and the vertebral artery. We also found more frequent abnormality in the circle of Willis in CVD than in the others, particularly in cerebral hemorrhage. The striate arteries are usually composed of the recurrent artery of Heubner branching from the anterior cerebral artery and the Aa. corporis striati from the middle cerebral artery, and they go together into the brain substance. However, it is occasionally found that a relatively large branching from the anterior cerebral artery constitutes the striate arteries besides the recurrent artery, or the Aa. corporis striati do not ramify directly from the middle cerebral artery but from the anterior temporal artery, a branch of the former. When these types of ramification were considered to be abnormal, abnormal constitution of the striate arteries was somewhat more frequently found in CVD than in the others. During our observations of acrylic resin casts of cerebral ar:eries, we noted node formations in the small cerebral artsries. These nodes were round or oval with diameters of 0.5 to 2.0 mm (Fig. 9). They were most frequently seen in the striate and Heubner’s recurrent arteries (approximately 75 %) and rarely in the cortical branches

40t

Fig. 10. Total number of node formations of arterial gutta percha casts in dog brains (20 cases).

References p . SSjX9

78

S. K A T S l J K l

where a vast amount of vascularization exists. They were much more common in elderly subjects than in younger ones, and the number of nodes was also larger in the elderly. For example, over the age of 40, all 8 cases had these nodes, the average number of nodes per brain being about 60, whereas under the age of 30, only half of the 4 cases had such a node and the average number was only 7. These node formations were also seen in the resin cast of the dog brain, and almost half the nodes were in the area of the striate arteries. In order to discover whether these nodes exist naturally or whether they were formed artificially when the material was injected, gutta percha was injected into bothcommon carotid and vertebral arteries. Nodes were found i n the same area (Fig. lo), so that it was considered that the nodes i n both casts of resin and gutta percha were of the same nature. Histological examination revealed that the nodes were formed by extravasation of gutta percha due to rupture of the arterial wall. The age of the dogs was not known and the relation of these nodes to the development of CVD is problematical in the dog. The formation of the nodes is presumably a n artifact. However, the age selectivity in human subjects and some relation to C V D may suggest that they are manifestations of some vascular pathology, in other words, locus minoris resistentiae. We are now working o n this problem by injecting gutta percha in human materials to make further analysis in CVD, especially in cerebral hemorrhage. 111. C L I N I C A L A S P E C T S

The patients with CVD admitted o r treated a s outpatients in 14 main hospitals in Japan for three years between the beginning of 1960 and the end of 1962 are sumT A B L E VTll T O I A L C A S t S W l r H C V D I N T H E 14 M A I N H O S P I T A L S OF J A P A N Jan. 1960-Dec. 1962; cases with initial attack; total number of all the patients: 339,491 ~

~

~~~

~

Cerebral infarction Cerebral thrombosis with attack Cerebral thrombosis without attack Cerebral embolism Cerebral infarction (thrombosis or embolism)

I049 25 1

I300 139 74

lntracranial hemorrhage Cerebral hemorrhage Subarachnoid hemorrhage

620 204

Cerebral infarction or intracranial hemorrhage

283

Transient cerebral ischemic attack Focal cerebral ischemic attack Transient cerebral ischemia with systeinic hypotension

166 83

Hypertensive encephalopathy Attack with unknown cause Others

127 75 23

Total cases with CVD

79

CEREBROVASCULAR DISEASE I N J A P A N

msrized in Table VIII (Reports on researches by Grantees, 1963). Out of 339,491 patients-3094 (0.9 %) were suffering from CVD, among whom cerebral thrombosis was over twice as frequnt as cerebral hemorrhage. The number of cases with cerebral embolism (139) was about one ninth of that of cerebral thrombosis (1300), and the number of subarachnoid hemorrhage (204) was about one third of cerebral hemorrhage (620). The number of patients with transient cerebral ischemic attack without infarction, including focal cerebral ischemic attacks and transient cerebral ischemia with systemic hypotension, was 249, the former 166 and the latter 83, respectively. The number of cases in which a definite classification could not be made was also listed. Although the ratio of cerebral hemorrhage to cerebral infarction in the Japanese population is considered to be higher than that shown by these figures, the patients with cerebral hemorrhage deteriorate more rapidly before they come to hospital. The total number of the admitted cases with CVD i n our own clinic in two recent years was 91, between March 1962 and March 1964 (Table IX). The type of lesion and its distribution was as follows: 53 cases with cerebral thrombosis, 18 with cerebral hemorrhage, 5 with the type undetermined whether thrombosis or hemorrhage, 2 with cerebral embolism or thromboembolism, one with cerebral infarction associated with polycythemia Vera, I2 with subarachnoid hemorrhage. Eleven died during admission, among which 10 were examined post-mortem in order to confirm our clinical diagnosis. Recurrent attacks were more frequently seen in cerebral thrombosis, in 17 out of 53 cases (32.1 %), and in subarachnoid hemorrhage in 4 out of 12 (33.3 We have been conducting detailed and systematic examinations in these cases, including those of cardiovascular status, blood coagulation, lipids profile, neurophysiology such as those of electroencephalography and cerebral circulation, cerebral angiography for the visualizaticn of intracranial as well as of neck arteries. Besides

x).

T A B L E IX

CVD

CASES A D M I I I E D TO O U K MEDICAL DEPARTMENT

From March 1962-March 1964. No. of cases

I. Cerebral thrombosis 11. Cerebral hemorrhage

53 18

ITT. Unclassified thrombosis or hemorrhage

5

IV. Cerebral embolism (or thromboembolism)

L

V. Cerebral infarction with

I

No. of deaths

Recurrent attacks

3 (3)* 5 (5)

17 1

1

polycythemia Vera

VI. Subarachnoid hemorrhage Total *( ) Indicate no. of autopsies. Refprmces p . 88/89

12

__

91

3

(2)

I 1 (10)

4 23

80

S. K A T S U K I

those, the aphasia test and psychometric evaluation have been performed in selected cases. We also found an abnormal metabolism of catechol bodies in CVD. ( 1 ) Cardiovascular status

Blood pressure, ocular fundi, and abnormal findings in ECG indicative of left ventricular hypertrophy or myocardial damage are summarized in Table X. Hypertxsion was most frequently associated with cerebral hemorrhage (94.4 %), and next with cerebral thrombosis (62.3 %). In subarachnoid hemorrhage it was in one fourth of the cases (25%). I n ocular fundi, severe changes such as those of KW 111 and IV were generally more frequent in cerebral hemorrhage than in cerebral thrombosis. Electrocardiographic abnormalities were found in 53.8 %, 53.9 %, and 41.7% of cases with cerebral thrombosis, hemorrhage and subarachnoid hemorrhage, respectively. Some of these findings were naturally reflected by the brain injury. Regarding ophthalmodynamometry, 60 cases were examined by the use of the Bailliart dynamometer. An increase in systolic and diastolic retinal arterial pressure was frequently found in cases with cerebral hemorrhage and infarction, and also in essential hypertension. The relation of retinal arterial pressure to occlusive lesions found in cerebral angiography was as follows. In one out of the two cases with complete occlusion of the right internal carotid artery, 15 % reduction in systolic retinal arterial pressure was found on the affected side, but no difference was found in the other case. There was no significant difference between the two sides in a case with incomplete occlusion of the r. middle cerebral artery and in cases with 70 % and 100 occlusion of the 1. middle cerebral artery and in cases with 40% occlusion of the r. posterior cerebral artery. TABLE X CARDIOVASCULAR

Ocular firnrii

Hypertension*

-

0

I. Thrombosis 11. Hemorrhage

1

111. Unclassified

2

1V. Embolism

2

V. Infarction with polycythemia Vl. Subarachnoid hemorrhage

Total

* systolic 2 140 and/or diastolic 2 90

srArus -

-.

I

I1

III

IV

?

card. damage)

10

20

5

0

15

5

4

4

2

2

1

4

28/52 (53.8%) 9/17 (53.9 %) 215 (40.0 %) 212 fibrill. (100 %) Oi 1 (0 X ) 5/12 (41.7 %)

3

1 4

54/91 (59.3 %)

12

ECG f L V H or myo-

16

2

1

29

10

3

21

46/89 (51.7%)

C E R E B R O V A S C U L A R DISEASE IN J A P A N

81

Whether an elevation of retinal arterial pressure in CVD is merely a manifestation of systemic hypertension, or is reflected to some extent by an increased vascular resistance in this particular portion of the arterial system requires further study. ( 2 ) Blood coagulation study

Determinations of bleeding time, whole blood clotting time, thromboplastin generation test (TGT), thrombotest, prothrombin activity, plasma fibrinogen content and fibrinolysis were performed in 75 cases with CVD, among which all of these tests were completed in 40 cases. Over 75 % of the cases were examined within three months following the onset. There was a trend that bleeding time (Duke’s method) somewhat shortened in the earlier stage of cerebral infarction and hemorrhage. Whole blood clotting time determined by Lee and White’s method was not substantially changed. The TGT was performed in plasma, because that in serum and platelets was unstable. An increased activity was demonstrated in I9 out of 33 cases (57.6 %) with the thrombosis, 8 out of 16 cases (50%) with the hemorrhage, and in 3 out of 9 cases (33.3 %) with subarachnoid hemorrhage. It was also noted that the increase was more marked in the 10 days following the onset. I n the thrombotest by the method of Owren, average values did not significantly differ according to the type of lesion, but in the hemorrhage, it was 30.8% within three months following the onset, and 104% thereafter, which may indicate that the activity increases with time. Prothrombin activity determined by the one stage method revealed a somewhat greater activity in cerebral thrombosis than in cerebral hemorrhage, but no conclusion was reached because of the wide variations. A significant increase in plasma fibrinogen content determined by a microkjeldahl method was more marked in the hemorrhage than in the infarction. Fibrinolysis was determined by the method of Fukutake, in which no significant difference was found among all types of lesion. Besides the tests above mentioned, no consistent findings were obtained in recalcification time, plasma thrombin time or platelet count, although the number of cases on which these tests were performed was too small to permit conclusions to be drawn. ( 3 ) 1-ipid study

Total lipids, total cholesterol, phospholipids and triglycerides were determined. Serum total cholesterol was determined by Zak-Henly’s method modified by Yoshikawa. Lipids were extracted by Bloor’s method. Phosphorus in the extract was determined by the procedure of Fiske-Subbarow, from which the value for phospholipids was calculated by converting the value for phosphorus into lecithin. Triglycerides were determined by the method of Carlson-Wadstrom, but adsorption of phospholipids was performed by column chromatography using Florisil (100-50 mesh) and Hyflo-super-cel according to Suehiro, iiistead of silicic acid as originally described. Details of the procedure and the preliminary results were described elsewhere (Katsuki et al., 1964b). The rcsults obtained in 55 cases with CVD and 57 age-adjusted controls are shown Refiwni

PS

p 88\89

S. K A T S U K I TABLE XI LIPID PROFILE

Subarachnoid Iieriiorrhage

Cerebral lietiiorrliage

Cerebral throtirhosi.r

Control

32 58.7 656 (543-790) 204 ( I 62-256) 193 ( I 59-234) 1 20 (93-1 55) 1.60 (1 .3 1-1.94)

97 54.0 607 (490-743) 190 (153-235) I79 ( 147-21 7) 87.2 (65.6-1 16) 1.88 (1.48-2.56)

..~

No. of cases Age, average Total lipids Total cholesterol

7 40.1

192* ( 168-220)

Phospholipids

172 (‘1 5 I 194) -

Triglyccridcs PLITG

103 (92-1 16) 1.69 (1.48- I .93)

I6 52.5 573 (483-7 13) 209 ( I 74-248) 212 ( 165-273) 90.5 (68-1 19) 2.51 ( I .89-3.50) ~

* Mean value, numbers in brackets

show the range of mean 1- S.D.

in Table XI. Among the cases with CVD, there were 7 with subarachnoid hemorrhage, I6 with cerebral hemorrhage and 32 with cerebral thrombosis. Total lipids were not much different between CVD and the controls. Total cholesterol in the ssrum also did not show much difference among the groups. In phospholipids, it was significantly elevated in the hemorrhage compared to that in the control, but not in the thrombosis and subarachnoid hemorrhage. In triglycerides, a marked elevation was noted in the thrombosis. The difference was statistically significant. The phospholipid to triglyceride ratio (PL/TG) was also significantly increased in hemorrhage but diminished in thrombosis. The explanation of these findings has not been readily obtained, but the elevation of phospholipids in the hemorrhage might be due to a release of these substances into the blood stream from the damaged brain tissue containing them in large amount. An increase in triglyceride level was reported by other investigators in coronary heart disease and also in cerebral infarction (Feldman and Albrink, 1964), and our results were well in accord with these reports. As for the time factor in lipid metabolism, the earlier the disease, the greater the elevation of phospholipids and the PLjTG ratio found in the hemorrhage, but triglycerides were more elevated as time elapsed, and accordingly the PL/TG decreased. Determinations of the a- and /Hipoprotein ratio and a- and @-lipoproteincholesterol have also been recently added to the study, and more detailed analysis will be made in the near future. ( 4 ) Neurophysiological stirdies

( a ) Elecfroeiire~~holo~raphy (EEG) A total of 140 EEG recordings on 69 cases was obtained, 42 cases being cerebral thrombosis, 14 cerebral hemorrhage, 8 subarachnoid hemorrhage, and 5 unclassified.

83

CEREBROVASCULAR DISEASE IN J A P A N

Most of the EEGs were recorded utilizing a 10/20 electrode system with an 8 or 12 channel electroencephalograph. The recording included photic stimulation (3-22 cis), hyperventilation (for 3 min), carotid compression test, carotid sinus massage, nitrogen inhalation and 10% carbon dioxide inhalation. A higher incidence of severely abnormal EEG was observed in the hemorrhage than in the thrombosis. Positive responses to the carotid compression and carotid sinus massage were more frequently observed in the CVD group than in the control, but no significant difference was found between the thrombosis and the hemorrhage. Ischemic response to carotid compression was elicited more frequently in cases with occlusive lesions shown in carotid and vertebral angiography. During nitrogen inhalation, slow wave responses were more common in CVD, especially in patients with abnormal EEG, and in the hemorrhage a slightly higher incidence of the positive response was observed than in the thrombosis. The carotid compression test was considered to be more useful than the nitrogen or carbon dioxide inhalation tests for the detection of abnormalities. ( 6 ) Cerebral circulation study Cerebral hemodynamics was studied by using the external counting method of intravenously injected radioisotope. Details of the procedure and the preliminary findings have been reported elsewhere (Katsuki et al., 1964~). Head circulation was diminished or retarded in a considerable number of cases with CVD, compared with 13 age-adjusted controls with essential hypertension (Table XI I). When these findings were considered in relation to occlusive vascular lesions demonstrated by cerebral angiography and to EEG findings, the latter two abnormalities were frequently seen in cases with reduced head circulation. It appeared to be more affected in the early stage of the hemorrhage, although such a trend was not demonstrated in the thrombosis. Among the parameters for head circulation, CBF (cranial blood flow) and TT (mean transit time) as described by Oldendorf appeared to be most sensitive for detecting abnormalities as shown in the table. T A B L E XI1 CEREBRAL CIRCULATION ~

No. of cases

Cerebral thrombosis

18

Cerebral hemorrhage

11

Subarachnoid hemorrhage Essential hypertension

5 13

Control

13

_

*

Mean

Rrferencrs p. 88/89

_

* S.D.

~

~

58 (41-73) 51 (3 1-72) 42 (33-52) 52 (3 1-73) 54 (34-76)

CBF (ml/min)

ism)

1 IY3*24*

10.4+2.1

TT

12481542

10.812.6

1314h-342

9.7I-tl.7

1521 k322

9.21t2.0

16001287

8.9 i 1.3

84

S. K A T S U K I

( 5 ) Cerebral angiography Cerebral angiography was performed in 46 cases by subclavian approach: 26 with cerebral thrombosis, 10 with hemorrhage, 9 subarachnoid hemorrhage, and one unclassified. The ages of the patients ranged from 21 to 79. Narrowing of the arteries by over 25% in diameter in any portion of the neck arteries as well as in cerebral arteries was considered to denote stenotic lesions. Out of 26 cases with thrombosis, 12 had positive stenosis (46.2%), in which the narrowing was found at 22 places, 8 extracranially and 14 intracranially. And more than half of the intracranial occlusive lesions were in the territories of the middle cerebral artery. In 5 out of 10 cases with hemorrhage, the anterior cerebral artery was shifted towards the unaffected side. T A B L E XI11 ANGIOGRAPHIC FINDINGS

Diagnosis

Thrombosis Hemorrhage Subarachnoid hemorrhage Unclassified

)

Arterial

cases

Sfenosis

shifi

26 (9)* 10 (7) 9 (1)

12 2 1

0 5 0

1 (1) 4h( 18)

Total

*(

No. of

0

Aneurysm or ma@rmation

0 0 5

0

0

-

__

-

15

5

5

Show complete angiogram of 4 neck arteries

In 5 out of 9 cases with subarachnoid hemorrhage, aneurysm or vascular malformation was found, probably related to the genesis of the hemorrhage (Table XIII). In the thrombosis, occlusive lesions of the arteries were considered to be somehow related to the pathogenesis of the disease. The incidence of occlusive lesions in our series was higher than that previously reported in Japan. The reason for this difference might be explained by the fact that the observations made by previous workers in Japan did not attain the complete angiogram of the 4 neck arteries. ( 6 ) Aphasia test

CVD is one of the most common diseases which often cause serious disturbances in language function. There has been increasing attention directed to the rehabilitation of aphasia, because speech disturbance may seriously affect social adaptation. To study the aphasia problems, there are four approaches : neurological, physiological, logopedical, and philosophical. These four aspects of aphasia mutually irteract. Our aphasia study was started by modifying ‘short examination of aphasia (Minnesota) (Schuell, 1957)’, with some consideration being given to the effects of physiological, neurological, and logopedical factors. The approach has been described in

CEREBROVASCULAR D I S E A S E IN JAPAN

85

detail elsewhere (Katsuki et a/., 1963b). Differences in letters of Japanese from those of English are as follows: (1) there is KANA (syllabary) and KANJI (ideograph) in Japanese, (2) there are neither alphabet nor spelling comparable to those of English. Therefore selected yKANJl were used for the ‘oral spelling test’. Among the 77 consecutive CVD cases, 22 (28%) were aphasics. Of these 22 cases 19 were studied with the Japanese version of the Minnesota test. In cerebral thrombosis, 24% (42 cases) were aphasics, and in hemorrhage 53% were so. In both of these, types I11 and V were in the majority, 84 % of the total. Education, occupation and other social factors did not interfere in the classification. Prognosis of type I was excellent (two cases were only transitory), and that of types 111 and V was poor, the latter especially showing no recovery even after 6 months or more. ( 7 ) Psychometric tests Tests for motion analysis and psychometric evaluation were done on selected cases according to the procedures developed in the University of Minnesota (Meier and French, 1960; Meier and Ayers, 1961 ; Meier, 1961). As for motion analysis, ballistic tapping, finger tapping, handwriting, and gait were tested in 27 cases. These tests were valuable for the detection and the objective evaluation of the defects. The tests were also found to be in good or excellent correlation with the laterality of the lesions; and sometimes even in the clinically non-affected limbs, the ability of these tappings was decreased. Psychometries with Japanese versions of the Minnesota Multiphasic Personality Inventory (MMPI) (Hathaway et al., 1963) and Wechsler Adult Intelligence Scale (WAJS) (Kodama et al., 1958) were applied to the consecutive CVD cases (37 cases). Out of these, 17 were unable to be tested due to severe mental or physical disabilities. The numbers of cases tested were 18 for WAIS and 13 for MMPI. In the 13 cases with cerebral thrombosis, IQs were mostly within the normal range : one borderline, one dull normal, 5 normal, 4 bright normal, and 2 superior. The MMPI test showed that 6 cases out of 13 were normal in personality, 3 abnormal and 4 unreliable. Although these tests are somewhat time-consuming and require good co-operation of the patients, valuable information may be obtained, when they are performed on testable cases, for the evaluation of psychic dysfunction in CVD. (8) Catecholamine metabolism

Urinary excretion of several catechol metabolites was determined in 55 cases with CVD and 21 controls. They were noradrenaline (NA), adrenaline (A), 3,4-dihydroxyphenylpyruvic acid (DPPA) and 3,4-dihydroxy-phenylaceticacid (DPAA). DPPA and DPAA were determined together as acid catechol (AC). An increase in AC excretion was found in 34 cases (61.8 %) but no increase in controls. This finding was particularly evident in the early stage of the disease, within 20 days following the onset, and also it was more marked in the hypertensives than in the normotensives. The increase was less frequent in subarachnoid hemorrhage. The increased AC excretion also appeared References p . 88/89

86

S. KATSUKI

to be associated with poor prognosis, repeated episodes, and with advanced fundoscopic findings. Age and sex did not affect the results. N A and A excretions were found to be lower in cases with increased excretion of AC. These results may indicate that abnormal metabolism of catechol bodies exists in CVD. ( 9 ) Rehubilitation

Medical and social rehabilitation of the patienis is also important. A special rehabilitation program for CVD patients has been set up since December 1961, and it has been applied to a total of 60 cases. Functional recovery was evaluated by testing muscle strength and activity of daily life (ADL). The latter is more valuable than the former, and the method of the Georgia Warmspring Foundation (G.W.S.F.)modified by Hattori was used for ADL evaluation (Table XIV). Motion analysis as previously described was also informative for the evaluation of the recovery. The scheme of the rehabilitation program is shown in Table XV. T A B L E XIV E V A L U A T I O N OF

ADL

Modified by Hattori of G.W.S.F.

I . Active daily life N (normal) G IG (good) G-

almost normal slightly restricted possible but restricted

2 . Inaciive daily l$e F (fair) P (poor) 0 (zero)

movement possible but not practicable movement partially possible movement impossible

T A B L E XV REHABILITATION

PROGRAM

1. Placing extremities in good alignment

11. Passive movement, forced muscle re-education 111. Exercise on bed

JV. Passive movement by patient himself Resistance movement V. Upper extremities: exercise for daily life Lower extremities: (a) exercise on bed (b) standing and walking i. on parallel bars ii. with crutches iii. gait without support (c) exercise for daily life

87

CERERROVASCULAR DISEASE I N JAPAN

T A B L E XVI R E C O V E R Y A N D T H E TIME O F S T A R T I N G O F T R A I N I N G .~

Within 3 months

___

3-6

month5

Over 6 months

~

To'a' ~~

Recovery of over 2 steps Recovery o f one step No recovery

14

4

2

20

4

0

2

6

1 -

Total

19

2 ~

6

2

5

-

-

6

31

Among the 60 cases, ADL was over G in 17 cases, which were excluded from further analysis. I n the remaining 43 cases with ADL below F, the recovery was much better in those without mental disturbance than in those with it. Mental disturbances were divided into two groups: one with a marked decrease in mental activity and unable to understand oral conversations (severe), and members of the other were able to understand each other, but with limitations (mild). No recovery was found in either of the two cases in the severe group, in 9 out of 10 cases in the mild group, and in 5 out of 31 casts (16 %) without mental signs. In these 31 cases, a recobery of over two steps was found in 20, and one step in 6, and it was more marked when the training started earlier. As illustrated in Table XVI, 18 out of 19 cases whose training started within three months improved, among which 14 cases (74%) showed a recovery of over two steps. In 6 cases whose training started over 6 months after the onset, 4 improved. Poor prognostic signs were a reduction in mental activity, a poor aptitude for training, and contractures of muscle or joints. The recovery of lower extremities was better than that of upper extremities. SUMMARY

Epidemiological and clinicopathological studies on cerebrovascular disease (CVD) in Japan, mainly based upon our own observations, are reviewed. For the epidemiological aspect, 1621 subjects in a selected community of Hisayamatown in Kyushu Island were completely followed for two years in order to determine the incidence of the vascular accidents. The annual incidence rate of CVD was roughly estimated 215 per 100,000 of the population. Out of 58 deaths, 22 cases (37.9 %) were autopsied: 15 died of CVD and 10 of heart diseases including coronary and congestive heart failure. As for precipitating factors of CVD, although not conclusive as yet, the following appeared to be significant: age over 60, heredity, neurological signs such as headache, dizziness and numbness of the extremities, abnormal ECG such as high amplitude R in the left leads or ST depression and retinopathy more than KW I. Serum total cholesterol level did not affect the evolution of the disease. References p. 88189

88

S. K A T S U K I

The focal vulnerability of the brain tissue for the development of CVD was discussed from the angioarchitectural point of view. A retrograde ramification was frequently seen in the arteries supplying the areas predisposed to vascular lesions. The significance of this arterial branching remains to be elucidated, but it may accentuate a circulatory disturbance in certain conditions. In our cast models of cerbral arteries, nodes were found in the small arteries more frequently in the areas of striate and Heubner’s recurrent arteries, which may be a reflection of the fragility of arterial walls. From the clinical aspect, various approaches for the understanding of this disease were described; cardiovascular status, lipids and blood coagulation studies, brain circulation study by radioisotope technique, EEG, cerebral angiography, psychometric evaluation, motion analysis, aphasia test and rehabilitation problems etc. The significance of these tests was discussed. These studies are still in progress, REFERENCES AKAZOME, T., (1964); Morphological studies on the localization of site of cerebral vascular lesions. Fukuoka Acta med., 55, 859-879. FELDMAN, R. G., AND ALBRINK, M. J., (1964); Serum lipids and cerebrovascular disease. Arch. Neurol., 10, 105-114. GOLDBERG, I. D., AND KURLAND, L. T., (1962); Mortalities in 33 countries from diseases of the central nervous system. WId Neurol., 3, 444-465. GORE,I., AND TEJADA, C.,(1957); The quantitative appraisal of atherosclerosis. A n w . J. Puthol., 33, 875-885. HATHAWAY, S. R., MCKINLEY, J. C., ABE,M., SUMITA, K., AND KURODA, M., (1963); Japanese Version of Minnesota Multiphasic Personality Inventory, Sankyodo (Kyoto). HATTOR[, I., (1963); Personal communication. ~ M A I T., , OTSUKA, H., HORIE,A., TAMARI, K., A N D MATAKE, H., (1960); Aortic atherosclerosis in West Japan. Fukuoka Acta rned., 51, 171-177. KAMEYAMA, M., (1961); A clinicopathological study on variations of the basal cerebral arteries Shinkei-shinipo, 5 , 758-767. KATSUKI, S.. HIROTA, Y . , AKAZOME, T., TAKEYA, S., OMAE,T., AND TAKANO, S.,(1964a);Epidemiological studies on cerebrovascular diseases in Hisayama, Kyushu Island, Japan. Part I : with particular reference to cardiovascular status. Jup. Heart J., 5 , 12-36. KATSUKI,S., MOTOZATO, Y . , AND TOMONAGA, H., (1963a);Visualization of the cerebral vascular tree by methacrylate injections. Kyushu J. med. Sci., 14, 301-304. KATSUKI, S., NACAE, K., OMAE, T., AND KUROIWA, Y.,(1963b); Minnesota short examination for aphasia modified for the Japanese, preliminary report with C.V.A. cases. Kyushu J. med. Sci., 14, 257-270. KATSUKI, S . , UZAWA, H., FUJIMI, S., SHIRATSUCHI, K., AND TTO, Y.,(1964b);Studies on blood lipids in cases with cerebrovascular diseases, a preliminary report. Jap. Heart J., 5 , 101-107. KATSUKI,S., UZAWA,H., TANAKA, K., FUKIYAMA, K., FUJISHIMA, M., AND OMAE,T., (1964~); Brain circulation studies by external counting of intravenously injected RTSA, a preliminary report. Jap. Heart J., 5 , 127-139. KODAMA, H., SHINAGAWA, F., AND INDO,T., (1958); Japanese Edition Wechsler Adult Intelligence Scale ( W A I S ) , with the permission of D. Wechsler and Psychological Corporation. Nihonbunka-kagakusha (Tokyo). KRISTENSON, A., (1947); On the question of the pathogenesis of the cerebral insults. Acta med. seand., 128, 200-2 1 I. MEIER,M. J., (1961); Interactions among personality variables, kinesthetic figural aftereffect, and reminiscence in motor learning. J. abnorm. soc. Psycho/., 63, 87-94. MEIER, M . J., AND AYERS, F. W., (1961);Quantitative effects of basal ganglia surgery on handwriting and gait. /.-Lancet (Minn.), 81, 70-73.

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MEIER,M. J., AND FRENCH,L. A., (1960); Quantitative assessment of handwriting and gait in Parkinson’s disease. Univ. Minnesota med. Bull., 31, 61 1-622. J . L., (1921); The basal arteries of the forebrain and their functional significance. SHELLSHEAR, J . Anat., 55, 27-35. SCHUELL, H., (1957); A short examination of aphasia. Neurofogy, 7 , 625-634. TAMARI, K . , (1962); Coronary atherosclerosis in West Japan; a statistic study based upon 627 autopsy cases, Igaku-kenkyu, 32, 23-33, TOMONAGA, H.,(1 961); Angioarchitectural studies on the cerebral arteries : in special reference to the arterial branching of the brain stem. Fukuoka Acta med., 52, 228-245. WHO (1959); Arterial hypertension and ischemic heart disease, preventive aspects. Technical report series, No. 231 (1962). (pp. 3-16). Reports on Researches by Grantees, Ministry of Education, Medicine (1 963), Nippon-GakujutsuShinkokai (Tokyo): Pathogenesis of cerebrovascular disease, in particular reference to the specificity of this disease in the Japanese (in Japanese), 469487.

90

Facilitatory and Inhibitory Effects of Hypothalamic-Hypophyseal Activity upon Spontaneous Paradoxical Sleep (EEG After-Reaction) MASAZUMT K A W A K A M I lkparttiirrri

of Pltysiology, Yokolianru UniverAity School of Medicine, Yokohama [Jupan)

INTRODUCTION

It has recently been demonstrated that when a rabbit is exposed to the proper conditions and stimuli (coitus, vaginal stimulation), it assumes a posture characteristie of sleep but its EEG pattern resembles one of arousal except in such areas as thc olfactory bulb and tract; part of the ‘sleep-like’ EEG pattern which immediately precedes it has been called the ‘EEG after-reaction’ by Kawakami and Sawyer (1958). Previous work on this EEG after-reaction has revealed that the thresholds for EEGarousal (evoked by stimulating the brain stem reticular formation) and EEG afterreaction (evoked by coitus or low frequency electrical stimulation of the hypothalamus or rhinencephalic centers, or a neutral pure tone o f 500 c/s) are sensitive to changes in sex hormone levels and in the citric acid cycle. Progesterone exerts biphasic effects on these thresholds, which can be correlated with estrous behavior and the facility with which the pituitary gland releases gonadotropic hormone (Kawakami and Sawyer, 1959; Everett, 1948; Sawyer and Everett, 1959; Kawakami and Sawyer, 1964). On the other hand, this EA phenomenon is blocked by adrenocorticotropic hormone, insulin or such inhibitory substances to the tricarboxylic acid cycle as fluoroacetate or malonic acid (Kawakami and Yoshida, 1964; Kawakami et al., 1964). The present investigation was pursued as to whether the distribution of spontaneous paradoxical sleep (EA) episodes might be influenced by the interactions of the hypothalamo-pituitary-gonadal axis. Furthermore, inasmuch as it had not been ascertained in detail which parts of the brain are responsible for generating, transmitting and controlling the EEG afterreaction, an attempt was made to investigate whether the basal hypothalamus and the adenohypophysis are essential to evoke the EEG after-reaction and its characteristic biphasic response pattern under the influence of sex hormones. M E T H 0D S

For this study ovariectomized and non-ovariectomized New Zealand White rabbits (2.5-3.5 kg) were used with permanently implanted concentric bipolar electrodes of

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stainless steel for EEG recording; both the 26 gauge tubing and core were insulated with Formvar except at their tips. These electrodes were fixed in position by dental cement attached to the calvarium and to screws embedded in the skull. Silver ball electrodes resting on the dura were used for cortical recording. The leads were soldered to a 14-hole Winchester receptacle anchored to the skull with the wires completely buried in dental cement. For recording, a 14-prong Winchester element with long wire leads was plugged into the receptacle. During the EEG recording sessions the rabbit was free to move around on a table in the shielded, soundproof recording chamber, to eat, drink, explore, and even to copulate with a buck introduced for the occasion. Thus the acute stress factors (Kawakami et a/., 1964), which usually disturb the EEG after-reaction pattern in short term experiments, were excluded. EEG recordings were taken continuously from about 36 h before the first injection of estrogen to 60-72 h after the second injection of estrogen, with a nine-channel EEG amplifier and inkwriter (Type EG-900, Sanei Co.). A two-channel EEG analyzer (Type EA-201, Sanei Co.) was used to analyze frequency components contained in the EEG, and transcribe them directly on the EEG record. Localized lesions in certain regions of the brain were made with a high frequency electrolytic lesion-maker using the coordinates from the stereotaxic atlas prepared by Sawyer et al. (1954). The lesioning electrode was of stainless steel wire insulated to within 1 mm of its tip. Estradiol benzoate was employed as the estrogen, and it was dissolved in sesame oil at a concentration of 1 mg/ml. It was administered as two subcutaneous injections of 0.1 mg each 24 h apart. Routinely, progesterone propionate in oil was injected subcutaneously at a dosage of 2 mg, 24 h after the second injection of estrogen. Following these treatments, the rabbit was usually highly estrous. For direct stimulation of the sex hormone ‘receptors’ in the brain to elicit the EEG after-reaction, chronic stereotaxic implants of 26 gauge stainless steel tubes with a minute amount of solid estradiol benzoate (0.1 mg) or progesterone propionate (0.1 mg) at their tips were made into various parts of the brain according to Sawyer’s method (1964). At autopsy the brains were fixed by perfusion with 10% formalin and the precise location of the electrode tips was determined histologically.

RESULTS

A . The spontaneous EEG after-reaction EEG patterns recorded during the period from arousal through the EEG afterreaction and correlated with the rabbits’ posture and behavior were investigated with the use of the frequency analyzer.

( I ) Characteristic EEG changes in paradoxical sleep pattern In 1959 Sawyer and Kawakami described the paradoxical sleep pattern under another name, the ‘phase of hippocampal hyperactivity’ in the EEG after-reaction to Rrfeerenccs p. 111/112

------------.--------*-POST. PS Fig. 1. EEG records from several regions of the rabbit brain, illustrating the appearance of the EEG after-reaction. EEG patterns of the alert stage are Seen in A (left half) and paradoxical sleep patterns in B and C. EEG patterns with spindle bursts in the frontal cortex, correlated with behavioral sleep, are seen in the latter half of C. The horizontal line indicates the phase of paradoxical sleep (PS). The dotted horizontal line indicates the precursory (PRE.PS) and the post paradoxical sleep phases (POST.PS).FC: Frontal cortex; LC: Limbic cortex; AMYG: Amygdala; DHPC: Dorsal hippocampus.

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coitus in the female rabbit. The EEG after-reaction in the rabbit includes episodes of ‘activated’ or ‘paradoxical’ sleep as well as periods of ordinary or spindle-burst sleep (Sawyer and Kawakami, 1959). During the transition from EEG spindle phase sleep to paradoxical sleep (EA) the rabbit behaved as follows: At first, its ears relaxed abruptly and hung down; then its head lowered gradually, and at the same time its pupils became greatly constricted; its eyeballs were fixed as though gazing absorbedly at some point, sometimes looking upward or undergoing horizontal nystagmoid movements. On rare occasions it was noted that the pupils were extraordinarily dilated for a moment, one or two seconds before becoming most constricted. During the time these pupillarv changes were occurring, the rabbit’s eyelids were almost closed and its head was hanging gradually lower until its jaw rested on the table. There occurred sporadic muscle twitches about the eyelids, the ears and the mouth, followed by similar muscular twitching along the limbs. The respiratory rate slowed to about one-half to one-third that of the sleep spindle stage and in one exceptional case a reduction from 63 to 18 per min was observed. The mean arterial pressure of the rabbit at rest was of the order of 90-120 mm Hg, and usually no appreciable changes in blood pressure were observed when the first spindle bursts appeared at the beginning of EEG spindle sleep pattern. However, during the episodes of paradoxical sleep a drop in arterial pressure of 20 to 30 mm Hg did occur. A similar finding has been reported for the cat during paradoxical sleep (Candia et al., 1962). The EEG changes were as follows: In the frontal cortex extremely low voltage fast waves of 25-30 cis continued to appear, and superimposed upon them were low voltage, 7-9 CIS waves. In the limbic cortex and the dorso-medial thalamus high amplitude ‘fast’ 0-waves of about 7.5-9 CISwere observed, analogous to hippocampal arousal waves, and in the hippocampus itself remarkably sustained &waves of this high amplitude and higher frequency kind were seen - 7.5-9 CISas compared with the more common 4-6 CIShippocampal arousal pattern. As the tonus of the ear and neck muscles decreased, the frequency of these regular 8-waves increased from 5.5-7 c/s to a maximum of 9-10 c/s. During this period the rabbit allowed its head to fall to one side. Concurrently, the high amplitude 0-waves, which had been quite regular, increased still further in frequency but decreased in amplitude to less than is regular for &waves. For more intensive study of both behavior and EEG during paradoxical sleep, this stage was divided into ‘Precursory’, ‘Proper’ and ‘Post’ substages. In the transition period from sleep spindle phase to paradoxical sleep, about 10-20 sec before the EEG changes occur the rabbit’s ears are slightly relaxed and gradually beginning to droop, and its eyes are either fixed as if gazing at a point or areslowly rotating in a horizontal plane. This is succeeded by the appearance of the following changes which shall be referred to as the Precursory Type and last about 3 to 20 sec: In the neocortex the spindle bursts which had occurred frequently are markedly depressed and a tendency toward arousal patterns begins to show; at the same time, in the hippocampus successive rhythmic slow waves (5-6.5 c/s) of high frequency begin to appear (an Rrferences p . 111/112

94

M. K A W A K A M I

example of this EEG pattern is indicated by the dotted line marked Per. PS below the records of Fig. IB). The EEG of this period, which exceeds 10 sec, often develops into the Proper Type (PS), as shown in Fig. 1 . The ‘Precursory’ and ‘Proper’ substages can not usually be observed without the prior display of sleep patterns. Conversely, in an abrupt transition from PS to EEG sleep spindle phase arousal patterns are usually seen briefly, and the ‘Post’ paradoxical sleep pattern which is about similar to the ‘Precursory’ one can be observed in some cases. The duration of this transition is variable, but under certain circumstances it lasts 5-20 sec. For example, even when the rabbit awakes from a paradoxical sleep state and stands suddenly, it sometimes remains standing entirely motionless, with fixed gaze, for 5-20 sec before pressing a pellet of feces from its anus, which is the normal behavioral act following a period of paradoxical sleep. The E E C during this peculiar prolonged arousal behavior is considered to be of the Precursory PS type. The onset of the characteristic EEG changes of paradoxical sleep is observed in sequence as follows; first in the reticular fomation and central gray at the level of the midbrain and the pons; second in the septum, hippocampus, and the posterior hypothalamus; third in the dorsomedial and centre median thalamus, dorsomedial and ventromedial hypothalamus, lateral hypothalamus and the mammillary body; last in the frontal and limbic cortices and the caudate nucleus. At the end of paradoxical sleep all the characteristic EEG patterns are suddenly and almost simultaneously replaced by POST. PS, sleep spindle or normal arousal EEG patterns without marked regional differences in recorded EEG. Furthermore, it usually takes more than 10 min from the time the rabbit assumes a sitting or lying position to the onset of the spontaneous EEG after-reaction. During the course of the after-reaction, if the rabbit is made to awaken and stand up (through presentation of such an arousal stimulus as a noise), it will stand motionless (as a statue) for 30 sec, sometimes as long as a minute, and then sit (or lie) down again, while the EEG after-reaction reappears with short latency, in most cases within 3 to 5 min. In case this phenomenon is not interrupted during its course and comes to a natural ending, the rabbit awakens, immediately presses fecal pellets from its anus, or instead, goes directly to the food bowl and eats ravenously. It may be said that this behavior is a common and characteristic sequel to the terminal stage of the EEG after-reaction. ( 2 ) On EEG,frequency components of parfsof the brain in fhe EEG nffer-reaction ( E A ) As regards the threshold of behavioral arousal, which was measured by high frequency electrical stimulation of the midbrain reticular formation, it took twice as great a stimulus to ‘wake’ the rabbit from the depths of the EA as it did from sleep or the sleep spindle stage of EEG pattern as previously reported (Kawakami and Sawyer, 1959). Such alterations in the threshold are shown as a schematic example in Fig. 2. EEG pattern analysis, however, confirmed that the EA pattern showed striking similarities to the EEG arousal patterns in several parts of the brain, as opposed to the relaxed behavior reported previously (Kawakarni and Sawyer, 1958; Sawyer and

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Kawakami, 1959). Consequently, the following questions presented themselves; what parts of the brain will show an activity level intermediate between the waking and sleeping states or reach even higher levels of activity than during arousal; or what other parts of the brain will show activity similar to the sleeping states defined above, or drop to il lower level of activity? To answer these questions, a frequency analysis of EEG records taken from various parts of the brain was made during the three previously described conditions. The EEG waves ranging in frequency from 2 to 30 cjs were divided into the following 5 bands: 2-4 cis, 4-8 cis, 8-13 cis, 13-20 c/s and 20-30 cjs. Representative records of the integrated values of these 5 bands over a 10-sec period are shown in Fig. 3. In the frontal cortex, while the rabbit lays on its side or prone in asleep-likestate, high amplitude slow waves with sleep spindle bursts were found to be predominant components of the EEG patterns. During the arousal period, fast wave components of 20-30 c/s increased. During the period of EA, fast wave components with frequencies of 13-30 cjs increased far more than during the arousal period, while the slow waves were decreasing as illustrated in Fig. 4A 'Frontal cortex'. The general trend of the height of EA histograms is followed in parallel with that of arousal, while the exact converse is the case with sleep spindle phase; that is, an opposite relation is found t o exist between the upward trend of EA and the downward trend of sleep spindle phase along the abscissa in the histogram. The tendency revealed in the frontal cortex is, in this respect, markedly different from that observed in the other areas of the brain. From these observations it may be inferred that the activity of the frontal cortex during EA is at the same level or higher than during the arousal period. This inference has been confirmed by fluctuations in evoked potential induced in the frontal cortex by electrical stimulation of the midbrain reticular formation (Sawyer and Khazan, I963 ; Kawakami, 1964). Tn the limbic cortex and the caudate nucleus, the histograms of arousal (the inteReferences p. 111/112

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grated band values of the EEG frequency components at the arousal period) parallel those of EEG sleep spindle phase. The EA histograms show fluctuations intermediate between arousal and sleep, though there are some areas where, in the frequency ranges of 2-8 cis, the EA pattern decreased in amplitude as compared with the other two states. In addition, some areas were found where the EA histogram though lying between the arousal and sleeping levels in the low frequency ranges surpasses them in the higher frequencies, as can be seen in the ventromedial hypothalamic nucleus and dorsomedial thalamic nucleus in Fig. 4A. These changes are very different from what was described above in the frontal cortex. On the other hand, in the midbrain and pontine reticular formation, centre median nucleus, and medial forebrain bundle a marked predominance of the EA is noted in the frequency ranges of 4-30 c/s, that is, in the wave components other than the &waves. In the hippocampus, posterior hypothalamus and the central gray (at the level of the midbrain), the integrated value of 8-13 c/s is the dominant one during EA. During alert behavior, or strong EEG arousal while lying down, the predominant frequency is 4-8 cjs. The frequencies of 4-13 c/s are, therefore, prevailing during arousal and EA. These frequencies are also commonly encountered in the medial forebrain bundle, centre median nucleus, and midbrain reticular formation during EA or arousal. On the other hand, in the medial preoptic area, anterior hypothalamus, median eminence, septum and the amygdala, the histogram of 2-8 c/s frequency components reveals the lowest values during EA and the highest during sleep stage. Further, these are found to be the areas where the EA histogram lies between the arousal and the sleeping levels in the 8-20 c/s frequency ranges (Fig. 4B). In the olfactory bulb, a noticeable feature is the occurrence of extrinsic high amplitude spindle bursts on the EEG, related to respiration. They are common during the beginning of rest, and they vanish during the EA period, as reported in 1958. Frequency analysis of the olfactory bulb, lateral preoptic area and anteromedial thalamus records revealed little change in frequency components as the animal passed from one state to another but all the values were at a minimum during EA. During the period of EA the activity levels in the frontal and limbic cortices are intermediate between those of arousal and sleeping, whereas, in general, it may be said that the brain stem reticular activating system, the hippocampus, and the medial forebrain bundle are essentially at peak levels of activity during the EA period. Almost no difference in height of the EA histograms through the 2-30 c/s frequency ranges is observed in the anterior thalamus and the subthalamus as compared with those of arousal and sleeping stages. This forms a category apart from the above described classification. With the frontal cortex, hippocampus, olfactory bulb, medial preoptic region, ventromedial hypothalamus and dorsomedial thalamus as examples there are at least 6 different histogram patterns mirroring changes in activity during sleep, wakefulness and EA in the various parts of the brain. References p. 1111112

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B. Distribution of episodes oJ’ spontarreous EEG after-reaction (paradoxical sleep)

In the anestrous or castrated female rabbit brought into estrus with estrogen and progesterone, the EEG after-reaction was induced, with a latency of 0.5 to 1 min, by electrical stimulation. Rectangular pulses of 5-6 c/s and 0.5 msec duration were applied to such regions as the septum, ventromedial hypothalamus and the aniygdala for 30 to 50 sec. The following facts are known about the threshold for induction of the after-reaction: (1) the estrogen priming, which consists of subcutaneous injections of estradiol benzoate at 0.1 mg in oil, daily for 2 days, usually does not lower the threshold appreciably nor does it bring the rabbits in heat; (2) progesterone (2 mg s.c., jn oil) on the third day (following 2 days of estrogen treatment) exerts a biphasic effect upon the threshold. During the first 5-7 h after a single injection of progesterone the threshold is lowered; and then, at 24 h after progesterone treatment, it is elevated above the initial level. The following experiment, therefore, was conducted to determine whether a similar biphasic change would be seen in the frequency of occurrence of the spontaneous EEG after-reaction during the animal’s progression into estrus, in comparison with the electrically-induced EEG after-reaction described above.

(I) Ovulation and distribution of episodes of spontaneous EEG after-reaction Even during anestrus paradoxical sleep patterns were observed. Continuous records made over a 24-h period from a large sound-proof chamber showed about 8 to 12 h of spindle sleep almost evenly distributed, and about 25 to 78 min of paradoxical sleep consisting of 20-30 episodes ranging from 5 sec to 7.5 min in duration (average 1.8 min). Four out of 65 ovariectomized rabbits showed only 2 paradoxical sleep episodes, as was expected, ranging from 20 sec to 1.5 min. No clear diurnal rhythm in the sleep patterns was observed in the anestrous rabbits as shown in Table 1. The difference between each value shown in the Table is statistically insignificant at 5 % level. The EEG changes and the accompanyjng behavior were followed from the anestrous stage through 72-96 h after injection of progesterone. As estrus progresses there is an increase in excitability of both the olfactory system

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and the diffuse activating system from midbrain to cerebral cortex, and the rabbit's movements become more sudden and faster (Kawakami and Sawyer, 1959; Kawakami, 1960). Such a disturbed, restless state occurs more frequently in rabbits with low thresholds to external stimuli. However, in the estrogen-primed animals the EA episodes with longest durations tended to be encountered in most cases during the first 5 h after injection of progesterone. Changes in the total amount of ordinary sleep and EA episodes during the course of

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Fig. 5. Bar graphs showing the total amounts of waking (open), EEG sleep spindle (stippled) and EA (black) stages for every 12 h of continuous recording, before (upper) and after (below) brain lesion in estrogen-primed rabbits. Bilateral lesions were localized in the MPO (A), the posterior ME (B), the VMH and its adjacent regions (C) or the caudal pontine reticular formation (D). Ordinates: Time in min. Abscissae: Time in h. Black bars: Amount of E A episodes during 12 h. Stippled bars: Sleep spindle phase. Open bars: Behavioral and EEG arousal phases. EEP: Subcutaneous injection of progesterone following estrogen treatment. MPO: Medial preoptic region. ME: Median eminence. VMH: Ventromedial hypothalamus. RF (P = 12): Caudal pontine reticular formation. Referencm p . 111~112

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estrus are illustrated in Fig. 5, where the total amount of EA episodes (except for the precursory EA stage) is compared with the total amount of spindle sleep stages for 24 to 48 h (during anestrus, after estrogen treatment, and following progesterone administration, respectively) and expressed as a ratio as described later. In 40 out of 52 cases there could be observed an increased total amount of EA episodes, in some with an increase but in others with a decrease of sleep spindle phase. An example is shown in Fig. 5A and C (upper part). Twelve of the animals seemed to increase in alertness as they became more estrous but the relative amount:of paradoxical sleep (as compared with the total amount of spindle sleep phase) actually seemed to have increased as seen in the histogram B of Fig. 5 (upper part). The curves represented in Fig. 8A show the variation of these ratios over at least a 72-h period. In the untreated ovariectomized rabbit during 'anestrus' the ratio of the duration of sleep spindle pattern (abbreviated SL) to that of paradoxical sleep (EA) was 7 : I to 14 : 1. For the 12 h following the injection of estrogen which included the peak of estrus, the ratio was 4 : 1 to 6 : 1 in 47 of 52 cases, i.e. the EA phase was lengthened relative to SL. Afterwards, with the disappearance of estrus, SL tended to increase relative to EA until the ratio SL/EA became 9 : 1-13 : 1. Furthermore, the effect of copulation on the distribution of EEG after-reaction episodes was investigated. MIN 10

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In 15 sexually mature female rabbits routine, subcutaneous injections of estrogen in oil at a dosage of 0.1 mg were made around 9 a.m. on days one and two, and they could mate the male. The frequency and duration of EA episodes and ordinary sleep were then analyzed for 48 h thereafter in 10 of these rabbits in which ovulation could be checked within 42 to 45 h following copulation. The following results were obtained. The total amount of episodes of the EA showed the largest increase for 2 to 6 h after copulation, that is the distribution of EA episodes reached its maximum within 2 to 4 h following copulation and was maintained at higher levels for about 12 h after copulation compared to the pre-copulation level. In Fig. 6 a representative example is schematically shown. The total amount of the EA episodes for 6 h after copulation was 1.5-4.3 (average 2.5) times as large as that (10'04")for the same hours before copulation. On the other hand, in 5 rabbits in which copulation did not induce ovulation the total amount of the EA episodes for 6 h following copulation reached 1.1-1.3 (average 1.2) times that of pre-copulation.

(2) Distribution of episodes of the EEG after-reaction in rabbits with crystalline estrogen or progesterone implanted in the brain The effects of minute amounts of crystalline estradiol benzoate or progesterone propionate implanted uni- or bilaterally in several parts of the brain - bilaterally in the midbrain reticular formation, unilaterally in the other parts - upon the distribution of EA episodes in the adult ovariectomized female rabbit have been studied. The minute quantities of these implanted hormones were too small to be effective systemically. Effects of subcutaneous injections of progesterone or estrogen in oil were investigated 10 to 21 days after the implantation of solid estrogen or progesterone in the brain. The experiments yielded the following results. In the ovariectomized rabbit without implanted estrogen a diminution of 27-35 % of the total amount of EA episodes as compared with pre-injection level was observed for 24 h following subcutaneous injection of 2 mg of progesterone. (a) Rabbit with minute amount of solid estrogen implanted. There was an appreciable difference in the distribution of episodes of EA for 24 h between the ovariectomized rabbit with estrogen implanted in the posterior median eminence and the ovariectomized one without estrogen, as illustrated in Fig. 7A. The amount of EA episodes after progesterone injection, however, was found to increase by 35-52 % for the first 12 h and to decrease by 4-25 % for the second 12 h against the control level in the rabbit with crystalline estrogen in the posterior median eminence; consequently the total amount of EA episodes for 24 h showed only an increase of 10-25 % as is shown in Fig. 7B. In the rabbit with crystalline estrogen implanted in the mammillary body or the posterior hypothalamus there was a tendency to a decrease in the amount of EA episodes during the 24 h after the injection of progesterone. That is, the change in the amount of EA showed the opposite of the alteration revealed in the rabbit with estrogen implanted in the medial preoptic region or the posterior median eminence. Refrrenresp. 111/112

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Fig. 7. Graphic presentation of distribution of EA episodes in rabbits with solid estrogen implant in the hypothalamus - medial preoptic region (MPO), N. periventricularis arcuatus (ARC), mammillary body (MM) - or midbrain reticular formation (RF) before and after subcutaneous injection of progesterone in oil. In Fig. 7A, the bars show the total amount of EA episodes for 24-h periods before (open) and after (stippled) estrogen implant in the posterior median eminence, medial preoptic area, mammillary body and the midbrain reticular formation. In Fig. 7B the bars show mean values (min) for the total amounts of EA episodes in each of 2 rabbits with estrogen implants in the same region during 24 h before (stippled) and after (stippled and hatched) subcutaneous injection of progesterone. Transverse section of hypothalamus showing site and size of the estrogen implant in the posterior median eminence and adjacent areas of the rabbit used for an example in Fig. 7.

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In the rabbit with crystalline estrogen in the midbrain reticular formation, during the first 24 h following injection of progesterone the total amount of EA episodes increased to some 1 .O-1.2 times pre-injection level. Unilateral implants of estrogen in the mammillary body as well as in the posterior median eminence elicited positive estrous behavior 4 or 5 days after these implants. ( 6 ) Rabbit with progesterone implanted. In the ovariectomized rabbit without any crystalline sex hormones implant, the total amount of EA episodes for 24 h following 2 subcutaneous injections of 0.08 mg estradiol benzoate in oil on consecutive days was found to be 1.2-1.4 times (average 1.3 times) higher than that of the pre-injection period, whereas in the ovariectomized rabbit with crystalline progesterone in the medial preoptic region the total amount of EEG after-reaction episodes could be found about 1.1-1.2 times that of pre-injection after subcutaneous injection of estrogen. Unappreciable influence of the administration of estrogen on the distribution of EEG after-reaction episodes was observed in the ovariectomized rabbit with progesterone implanted in the median eminence. After estrogen injection, the total amount of EA episodes was about 1.1 times the pre-injection amount in the ovariectomized rabbit with progesterone implanted in the mammillary body. In rabbits with progesterone implanted in the midbrain reticular formation the total amount of EA episodes after estrogen injection did not reveal so marked an increase as in the reverse case (progesterone injection after estrogen implantation). The above mentioned results may indicate that solid progesterone implanted in the brain exerts an unappreciable effect upon the spontaneous EA. A histogram showing the interrelationship between the increase or decrease of EA distribution and the location of solid estrogen or progesterone implantation in the brain is elucidated in Fig. 7. C. Determination of the cerebral structures responsible for paradoxical sleep under the influence qf sex hormones

In order to establish some correlation between the fluctuations in paradoxical sleep and pituitary activation, localized lesions were made in the following areas of the brain : medial preoptic region, ventromedial hypothalamus, posterior and lateral hypothalamus, posterior tuberal region, centre median of the thalamus, dorsomedial and ventromedial thalamus, midbrain reticular formation and central gray matter, pontine reticular formation and trapezoid body. On the basis of results three groups were defined. The first consisted of those rabbits which had received lesions in the preoptic region, dorsomedial hypothalamus, lateral hypothalamus, midbrain reticular formation or central gray substance, i.e., areas which have a close relationship to the autonomic nervous system and are connected with the limbic system. In these animals the total time spent in paradoxical sleep during the first 6-12 h after injection of progesterone tended to be greater than that during the remainder of estrus or anestrus. The SL/EA ratio was markedly decreased in each instance, reaching a minimum References p . 111/112

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Fig. 8A Fig. 8B Fig. 8C Fig. 8. Graphs showing the change of the ratio of duration of the sleep spindle pattern to duration of the paradoxical sleep in the course of estrus. (A) Control ovariectomized rabbits without brain lesion. (Bj After lesioning the medial preoptic region, central gray, and midbrain, midpontine and caudal pontine reticular formations. (Cj After lesioning the ventromedial hypothalamus, premammillary area and ventromedial hypothalamus, periventricular arcuate, posterior median eminence and periventricular arcuate, or the pituitary gland. E, EE First and second injection of 0.084.1 mg estrogen. P: Injection of 2 mg progesterone. RF: Reticular formation. ME: Median eminence. Abbreviations : MPO : Medial preoptic area. PMA: Premammillary area. ARC: N. periventricularis arcuatus. C G : Central gray. VMH: Ventromedial hypothalamus PIT: Pituitary gland.

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Fig. 9. Localized lesions in the diencephalon, midbrain and the caudal pons. (A, B, C and D) Transverse and sagittal sections through the hypothalamus showing lesioned areas (blackened). (E and F) Transverse and sagittal sections through the midbrain or the caudal pontine reticular formation showing bilaterally lesioned areas (blackened). Note that the lesions which were shown in B, C and D block the characteristic changes in duration of the paradoxical sleep in progress of estrus.

value during the first 12 h after progesterone administration. Several such cases are illustrated in Fig. 8B. When this ratio was followed through estrus, its course was found to be almost the same as before the lesion. The second group consisted of rabbits in which the lesions were located in the posterior hypothalamus, pontine reticular formation or the trapezoid body (see Fig. 9 for representative examples of site and size of lesions). In this group paradoxical sleep patterns seldom appeared before estrogen-progesterone treatment, as an example in histogram D of Fig. 5 shows. Following treatment with estrogen and progesterone the paradoxical sleep patterns which appeared were very similar to those of the unlesioned estrous rabbit, and the SL/EA ratio showed a biphasic course typical of the normal rabbit. References p. I I I j l t Z

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Rec::itly it has been reported that in the cat paradoxical sleep patterns disappeared entirci, after lesioning of the trapezoid bodies or the pontine reticular formation (Jouvet, 1962). in the present experiments, however, such a lesion (at the border between pons and medulla, illustrated in Fig. 9F) did not block the appearance of paradoxical sleep, especially after estrogen-progesterone treatment. The curves showing variations in the ratio of these two groups are presented in Fig. 8B. The last group included the animals prepared by bilateral destruction of the posterior tuberal region, the ventromedial hypothalamus (Fig. 9C), the pituitary gland (Fig. 9B), or the pre-mammillary area (Fig. 9D). The first two of these nuclear areas are well recognized as control ‘centers’ for the gonadotropic activities of the adenohypophysis - enhancing or preventing secretion ; the last region is involved in regulating sexual behavior. Following estrogen-progesterone treatment these rabbits failed to exhibit any clear-cut alterations either in the duration of the phases of paradoxical sleep or in the SL/EA ratio during the course of estrus, Their features, however, were presented in a fashion more typical of anestrus. Several representative cases are illustrated in Fig. 5B and C (lower figures) and Fig. 8C. A similar situation (i.e. no noticeable response to the estrogen-progesterone treatment) was observed in the rabbits in which the lesions involved the adenohypophysis itself. DISCUSSION

The paradoxical sleep pattern, which is a part of the EEG after-reaction, differs from the EEG pattern accompanying ordinary sleep. This difference was especially noticeable in the neocortex where, during the period of paradoxical sleep, there was a marked decline in the 2-4 c/s component of the wave patterns. In the midbrain reticular formation which is recognized as exerting a strong activating influence upon the EEG of the neocortex (Magoun, 1963), certain frequency components showed a slight tendency to increase during paradoxical sleep; these were in the ranges of 4-8 cis, 8-13 cis and 20-30 c/s, as described previously. Also, in the medial forebrain bundle, the hippocampus and the midbrain central gray, which have a close relationship with autonomic nervous function and emotional reactions, the 4-1 3 c/s wave components underwent changes similar to those of the midbrain and poiitine reticular fomations. In the hippocampus especially, a so-called hyperarousal wave of high amplitude and 7-10 c/s appeared to dominate, and here, at the same time, the fast wave components of 20-30 c/s showed a more dominant tendency during paradoxical sleep than during the arousal period. Thus, according to the accepted classifications of EEG patterns (Hess et al., 1953; Walter et al., 1946; Gibbs and Gibbs, 1950), it is concluded that during the period of paradoxical sleep most parts of the diencephalon, and subcortical regions as well, are activated. Recently, Okuma and Sekiguchi (1962), Yamamoto and Kido (1962), Sawyer and Khazan (1963) and Kawakami (1964) found that neocortical potentials evoked by stimulation of the midbrain reticular formation of the rabbit during the period of paradoxical sleep were almost the same as evoked potentials in the alert animal. Winters (1963) also reported that the evoked response to an auditory stimulus was

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reduced in amplitude or absent in the midbrain reticular formation and reduced in the medial geniculate body both during paradoxical sleep and in the alert, distracted cat. These facts suggest that the activity of the reticular formation in projecting to the neocortex in paradoxical sleep is similar to that during the arousal stage. Furthermore, it has been reported that in the phases of paradoxical sleep the occurrence of several types of eye movements in light sleep or during dreaming was observed (Aserinsky and Kleitman, 1955; Dement and Kleitman, 1957). On the other hand, our experiments have also shown that with the appearance of the EEG after-reaction including the paradoxical sleep phase the following situation is noticed: (1) the thresholds of EEG and behavioral arousal t o stimulation of the midbrain reticular formation are elevated; (2) blood pressure is depressed; (3) during the EA phase the EEG patterns in the olfactory bulb, lateral preoptic and anterior medial thalamic areas are somewhat similar to those of the sleep stage; (4) the respiratory rate is markedly decreased; and (5) if a rabbit is kept in an arousal state for 12 successive hours and observed immediately afterwards, the amount of paradoxical sleep is increased relative to general sleep spindle bursts. All these data lead t o the conclusion that the EEG after-reaction is a kind of sleep, but rather different from both light and deep sleep. A humoral mechanism in the control of nervous functions resulting in paradoxical sleep i s inferred from the long latency with which sleep spindles appear in the EEG record as an indispensable precursor of paradoxical sleep. Once started PS is difficult to interrupt and if interrupted by afferent impulses it may recur in less than 4 min. In the estrous rabbit the total amount of EA episodes during 6 h after copulation with ensuing ovulation increased to average 2.5 times the amount observed during 6 h before copulation, and subsequently decreased. Furthermore, this phenomenon was induced by injection of the appropriate dosage of luteinizing hormone, human chorionic gonadotropin, oxytocin and some pituitary principles as well as the precursors and members of the tricarboxylic acid cycle, and it was blocked by the administration of a large amount of progesterone, antifertility agents, atropine, morphine, or various hypnotic-soporific agents (Kawakami and Sawyer, 1961; Kawakami et al., 1963; Sawyer, 1962; Sawyer et al., 1964; Yanagida et al., 1964). On the other hand, it is well known that within an hour post-coitus sufficient ovulating hormone has been released to induce ovulation (Fee and Parkes, 1930; Westman and Jacobson, 1936; Everett, 1961). Another fact is that coitus or the injection of ovulatory dosages of pituitary or placental gonadotropins cause marked elevations in progestin output from the rabbit’s ovaries (Hilliard et al., 1963). Furthermore, the EEG after-reaction threshold to direct electrical stimulation of certain areas of the brain is lowered in correlation with estrus. From these various data it is supposed that the central mechanism which induces the fluctuations of these phenomena during the course of estrus is adjusted and triggered in those regions of the brain which are closely related to hypophyseal hormone release. In the electrolytic lesion experiments on the olfactory bulbs, septum, fornix, medial thalamus and brain stem it was revealed that the posterior tuberal region, pre-mammillary region or the adenohypophysis are essential for the evocation of the biphasic References p . ~ l l I I I12

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response of spontaneous paradoxical sleep in the estrous rabbit. It seems that both the facilitatory and the inhibitory influences of the sex steroids upon the occurrence of paradoxical sleep are attributable to, or mediated by, their actions on the above-named regions, above all on the posterior median eminence as the ‘final common path’ of the hypophyseal stalk. In other words, this kind of sleep seems to be markedly affected, ultimately, by adenohypophyseal activity. This is supported by the observation (Davidson and Sawyer, 1961) that it is the posterior tuberal region that is involved in the negative feedback control mechanism of adenohypophyseal hormone release when estrogen is increased in this region. A minute amount of crystalline estrogen implanted in the medial preoptic region, median eminence of the posterior tuberal region, pre-mammillary region or the midbrain reticular formation has a considerable influence upon the distribution of EA episodes as well as on the characteristic patterns of the sexual behavior as reported in the present experiments. In these regions there may well be numerous receptor elements which are directly sensitive to estrogen and are also influenced in a coordinated manner by endogenous and exogenous hormones, acting as mechanisms controlling synthesis and release of gonadotropic hormones in the brain. The present influencing experiments point out sex steroids as crucial elements of the internal environment influencing stages of sleep and wakefulness.

SUM MARY

Variations i n the frequency and duration of the spontaneous EEG after-reaction were studied continuously over a period of 72-96 h, from anestrus to estrus, in ovariectomized rabbits primed with estrogen and progesterone. The records were made from electrodes permanently implanted in cortical and deep regions of the brain, and the following sequences of EEG and behavioral changes have been observed: (1) Study of the EEG patterns and their frequency analysis revealed striking differences between the patterns of normal sleep and those of the EEG after-reaction, the latter being rather similar to the arousal pattern except that of the olfactory bulb. The lowest integrated value of EEG frequency components of 2-30 c/s for the period of EA out of those for EEG arousal, sleep spindle and EEG after-reaction stages was observed in the olfactory bulb, anterior medial thalamus and lateral preoptic region; the highest in the hippocampus, medial forebrain bundle, midbrain and pontine reticular formation. On the other hand, in the other regions the integrated value for the period of alertness lies between those for EEG after-reaction and normal deep sleep. (2) No clear diurnal rhythm of the EEG after-reaction existed in the non-treated, ovariectomized rabbit and the normal adult male. (3) In the estrous rabbit the total amount of EA episodes during 6 h after coitus with ensuing ovulation increased to about 2.5 times the amount observed during the 6 h before copulation. (4) In the ovariectomized female rabbit without implantation of solid estrogen, the

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11 1

total amount of EA episodes after the subcutaneous injection of 2 mg progesterone in oil showed a tendency to decrease, compared to pre-treatment level. The total amount of EA episodes increased to 1.2-1.5 times that of the pre-injection period during the 24 h following the subcutaneous injection of 2 mg progesterone in oil in the ovariectomized female rabbit with a minute amount of solid estrogen implanted in the medial preoptic region or posterior median eminence whereas in the ovariectomized rabbit with crystalline estrogen implanted in the midbrain reticular formation and mammillary region there could not be observed so remarkable an increase in the total amount of EA episodes. ( 5 ) The ratio of the total number of hours of spindle burst sleep to that of paradoxical sleep decreased with the onset of estrus. This ratio was lowest during the first 12 h after injection of progesterone in the ovariectomized, estrogen-primed rabbit; i.e. there were relatively more paradoxical sleep phases during estrus. (6) Localized lesions in the posterior tuberal region, the ventromedial hypothalamus or the pre-mammillary region blocked the biphasic fluctuation of this ratio. Lesions of the septum, dorsomedial thalamus, posterior and lateral hypothalamus, midbrain reticular formation and central gray substance, pontine reticular formation or the trapezoid body did not block this biphasic effect of progesterone in estrogenprimed ovariectomized rabbits. It may be inferred from these data that the influence of estrogen and progesterone upon the mechanism which results in the induction of the EEG after-reaction i s localized in the basal hypothalamic regions and the midbrain reticular formation.

ACKNOWLEDGEMENTS

The authors wish to express their appreciation to Professors C . H. Sawyer, J. W. Everett and T. Tokizane for their interest, to Drs. E. Terasawa, H. Negoro and S. Ishida for their kind technical assistance and to Dr. C . K. Haun for help in English grammar and expression. This work was supported by a grant from the National Institutes of Health, U.S. Public Health Service (NB-03860-2). REFERENCES N., (1955); Two types of ocular motility occurring in sleep. J . appl. ASERINSKY, E., AND KLEITMAN, Physiol., 8, 1-6. CANDIA, O., FAVALE, E., GIUSSANI, A., AND ROSSI,G. F., (1962); Blood pressure during natural sleep and during sleep induced by electrical stimulation of the brain stem reticular formation. Arch. ital, Biol., 100, 216-233. DAVIDSON, J. M., AND SAWYER, C. H., (1961); Effects of localized intracerebral implantation of oestrogen on reproductive function in the female rabbit. Acta endocr., 37, 385-393. DEMENT, W., AND KLEITMAN, N., (1957); Cyclic variations of electroencephalogram during sleep and their relation to eye movements, body motility and dreaming. Electroenceph. clin. Neurophy.~iol.,9, 673-690. EVERETT, J. W., (1948); Progesterone and estrogen in the experimental control of ovulation time and other features of the estrous cycle in the rat. Endocrinology, 43, 389-405.

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EVERETT, J. W., ( I 961); The mammalian female reproductive cycle and its controlling mechanisms. Sex and Internal Secretions. W. C. Young, Editor. Baltimorc, Williams and Wilkins (pp. 495-555). FEE,A . R . , A N D PARKES, A. S., (1930); Studies on ovulation. J . Physiol. (Lond), 67, 383-388. GIBBS,F. A., AND Glees, E. L., (1950); Atlas of Electroencephalography. Vol. 1. Cambridge, AddisonWesley Press. HESS,R., KOELLA, W. P., A N D AKERT,K., (1953); Cortical and subcortical recordings in natural and artificially induced sleep in cats. Electroenceph. clin. Neurophysiol., 5, 75-90. HILLIARD, J., ARCHIBALD, D., AND SAWYER, C. H., (1963); Gonadotropic activation of preovulatory synthesis and release of progestin in the rabbit. Endocrinology, 72, 56-66. JOUVET,M., (1962); Recherches sur les structures nerveuses et les mkcanismes responsables des differentes phases du sommeil physiologique. Arch. ital. Biol., 100, 125-206. KAWAKAMI, M., (1960); Sex Hormones and Brain. Tokyo, Kyodo-isho (in Japanese). KAWAKAMI, M., (1964); The humoral influences upon the distribution of the paradoxical sleep episodes in the rabbit. Brain Nerve, 1, 828-835 (in Japanese). E., (1964); Influence of immobilization stress upon KAWAKAMI, M., NEGORO,H., AND TERASAWA, the paradoxical sleep (EEG afterreaction) in the rabbit Submitted to Jup. J . Physiol. KAWAKAMI, M., AND SAWYER, C. H., (1958); Some effects of hormones on electrical activity and thresholds in the brain. Program 40th Meetin2 Endocr. Soc. (p.39). KAWAKAMI, M., A N D SAWYER, C. H., (1959); Neuroendocrine correlates of changes in brain activity thresholds by sex steroids and pituitary hormones. Endocrinology, 65, 652-668. KAWAKAMI, M., A N D SAWYER, C. H., (1961); Effects of steroid antifertility agents on brain function in rabbit. Science, 134, 1430. KAWAKAMI, M., A N D SAWYER, C. H., (1964); Conditioned induction of paradoxical sleep in the rabbit. Exp. Neurol., 9, 470-482. KAWAKAMI, M., TERASAWA, E., AND NEGORO,H., (1963); Blocking effects of anesthetics, hypnotics and sedatives on paradoxical sleep. Proc. 2151 Meeting, Nihon No-Jhinkei-geka Gakkai (p. 65). (Abstract in Japanese.) KAWAKAMI, M., AND YOSHIDA,K., (1964); Influences of the related substances of the tricarboxylic acid cycle upon the paradoxical sleep. Submitted to Jap. J. Physiol. MAGOUN, H. W., (1963); The Waking Brain. Springfield, Thomas. T., AND SEKIGUCHI, A., (1962); Neurophysiology of sleep. 1.Seishinigaku, 4, 19-818 (in OKUMA, Japanese). C. H., (1964); Induction of estrous behavior in the ovariectomized rabbit PALKA, Y. S., AND SAWYER, by estrogen implants in the hypothalamus. Amer. Zoo]., 4, 289. SAWYER, C. H., (1962); Mechanisms by which drugs and hormones activate and block release of pituitary gonadotrophins. Proceedings of the First International Pharmacological Meeting. B. Uvnas, Editor. Oxford, Pergamon Press (pp. 27-46). SAWYER, C. H., AND EVERETT, J. W., (1959); Stimulatory and inhibitory effects of progesterone on the release of pituitary ovulating hormone in the rabbit. Endocrinology, 65,644-651. SAWYER, C. H., EVERETT,J. W., AND GREEN,J. D., (1954); The rabbit diencephalon in stereotaxic coordinates. J. comp. Neurol., 101, 801-824. SAWYER, C. H., AND KAWAKAMI, M., (1959); Characteristics of behavioral and electroenccphalographic after-reactions to copulation and vaginal stimulation in the female rabbit. EndocrinoloRy, 65,622-630. SAWYER, C. H., KAWAKAMI, M., AND KANEMATSU, S., (1964); Neuroendocrine aspects of reproduction. J . quant. Biol., In the press. SAWYER, C. H., A N D KHAZAN, N., (1963); From private communication. W. G., MILD, D., COBB,W. A., WHITTERIDGE, D., GREVILLE, G . D., AND HEPPENSTALL, WALTER, M. E., (1946); Electroencephalography. New York, MacMillan. D., (1936); Uber Ovarialveranderungen beim Kaninchen nach HypoWFSTMAN, A., AND JACOBSON, physektomie. Acta ohstet. gynec. scend., 16, 483-508. WINTERS,W. D., ( I 963); Click responses in cortical and subcortical structures during various stages of wakefulness and sleep. Pharmacologist, 5 , 266. YAMAMOTO, K., AND KIDO,R., (1962); Neurophysiological studies on the nature of sleep. J. Sei.7hinigaku, 4, 821-830 (in Japanese). T., MANO,H., A N D NAKAMURA, Y., (1964); Effects of short chain fatty acids upon YANAGIDA, paradoxical sleep. Proc. 13th Meeting, Jap. Electroenceph. Soc. (p. 2). (Abstract in Japanese.)

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Behavioural and Electrophysiological Study of Drugs Affecting Brain and Motor System in Animal Experiments RYONOSUKE KIDO, KEN-ICHI YAMAMOTO

AND

AKIRA MATSUSHITA

Department of Neuropharmacology, Shionogi Research Laboratory, Shionogi and Co., Lid., Osaka (Japan)

In our laboratory, electrophysiological and behavioural analyses of drug effects on the brain and motor system have been carried out during the past 5 years. A series of our investigations is introduced in the following three parts. P A R T I . S T U D Y O F THE N O R M A L

EEG

OF THE CAT

Introduction

Numerous studies of the normal EEG of the cat have been carried out and many postulations have been advanced by many workers, but not a single one has been generally accepted owing to differences in experimental methods. Nakajima (1955) and Tokizane (1958b) investigated the normal EEG from restrained cats in acute experiments, but were troubled by the invasion of operation effects and the remaining effect of narcotics. Rheinberger and Jasper (1937), Koella et al. (1951), Bradley and Elkes (1953) recorded the normal EEG of unanaesthetized and unrestrained cats in chronic experiments using the implanted electrode technique, but in these experiments also implantment techniques were very difficult and the relations between behaviour and EEG were not observed minutely. Kobayashi et al. (1958) devised a simple technique of electrode implantation and clarified the relationship between electrocorticogram and behaviour in cats. The experimental conditions of EEG were divided into two methods, that is the ‘acute’ and ‘chronic’ cat, but in both cases comparisons of EEG and level of consciousness were very rare. The purpose of the present study is to compare the normal EEG patterns in ‘acute cats’ -the EEGjust after operation from cats restrained on the stereotaxic instrument -with those in ‘chronic cats’ -the chronic experiment using the implanted electrode technique. Materials and methods Experimental animals: 80 adult cats of both sexes weighing about 3 kg were used for the experiments. In order to tame the animals and to prepare them for the operation, the cats were given nutritious food for 2 weeks. References p . 147-149

1 I4

R . K I D O , K . Y A M A M O T O A N D A. M A T S U S H I T A

TABLE 1 I N S E R T I O N SITES OF D E P T H

S T E R E O T A X I C ATLAS)

ELECTRODES (JASPER’S

(From Yamamoto, 1959) No. of channel

I 11 111

IV V VI VII VITT

Combination of electrodes Left frontal 1 Left occipital Anterior sigmoid gyrus (Ant. sig.) Caudate nucleus Thalamus Hippocampus Amygdala Reticular formation

Points of depth electrodes

Indifferent electrode Right occipital Indifferent electrode (C)

(T) (HI (A) (RF)

Frontal 16.0 7.0 2.0 13.0 2.0

Lateral 4.0 3.0 8.0 9.0 3.0

Horizontal 1-4.0 0.0 +7.0

-6.0 -3.0

Electrodes: In consideration of the influence to the cortex and the difficulty of electrode insertion, stainless steel screws were used for cortical and skull electrodes. The concentric stainless steel electrode used for recording electrical activity of subcortical nuclei in acute cats consisted of an outer stainless steel syringe needle (diameter 0.8 mm) with a thin stainless steel wire (diameter 0.25 mm) inside. The surfaces of the inner and outer needles were coated with Kashu, a kind of varnish. Bipolar ;tainless steel electrodes (diameter 0.2 mm, distance between electrodes 0.5 mm) insulated with Kashu except for tips were used for recording subcortical electrical activity in the chronic cats. The electrical insulation of each electrode was checked before and after the experiments. Application points of electrodes: Skull electrodes were applied on the frontal, parietal and occipital areas. The indifferent electrode was placed on the nasal bone. The insertion points of the subcortical electrodes are described in Table 1. EEG recording: For surgery in the acute cat, light inhalation anaesthesia with ether and N2O was used. The EEG was recorded 2-3 h after operation in order to avoid the influence of anesthesia. In the chronic cat, cortical and subcortical electrical activity was recorded 7-10 days after operation. Acute and chronic cats used for experiments were placed in a sound-proofed and shielded room. The operator outside of this room observed the behaviour through a one-way window and recorded the EEG. Confirmation of electrode point ylacep?ient: After finishing the series of experiments all cats were sacrificed and in each acute and chronic cat the position of the inserted electrode points was checked histologically. Results ( I ) Normal EEG from skull electrodes of the acute cat The EEG patterns were classified into 4 stages (A, B, C and D) according to frequency and wave form as follows. Stage A: 30-80 p V , 20-30 cjs waves were observed. When the acute cat was stimulated by external stimuli, such waves could immediately be observed in all leads. At this

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stage, the mean average of the respiratory rate was 29 per min, which is the most frequent rate throughout all stages. Stage B: 30-150 p V , 10-13 c/s waves were seen that somewhat resembled the awaves in the human EEG. These waves could occasionally or repetitively be seen in the low voltage fast waves, and showed a tendency to appear dominantly in the EEG from the frontal and parietal areas. Stage C: 150-250 p V , 5-8 c/s fast waves were observed especially in the occipital area when the amplitude of the EEG of all leads increased. The respiratory rate at both B and C stages averaged 26 per min. Stage D : Irregular slow waves with high amplitude, occasionally accompanied with sharp waves of 200-400 pV. Moreover, spindle burst of 150-350 p V , 1 1 cjs appeared mainly in the EEG from the frontal and parietal areas. The mean average of the respiratory rate at stage D is 24 per min. The EEG pattern of stage A caused by external stimuli was not always transferred into that of stage D along the above-described course. Although the EEG patterns of each stage could be clearly classified, they were easily affected by the kind or intensity of the stimuli, and even by changes in the experimental conditions. The results are summarized in Table 11. In general, no right-left differences were observed. ( 2 ) Normal EEG from the cortical and subcortical electrodes of the acute cat The characteristics of the EEGs from cortical and subcortical leads were investigated such as those from the anterior sigmoid gyrus, caudate nucleus, thalamus, hippocampus, amygdala and midbrain reticular formation, corresponding to each of the above 4 stages. Stage A : The hippocampal &waves which consist of regular rhythmical waves of 150 p V , 2-4 c/s were usually observed. Also, the 2-4 c/s frequency band in the spectrum analysis of the hippocampal EEG increased markedly. However, the traces from all other leads showed 20-80 p V , 20-30 cis waves, similar to those i n the EEG from the skull electrode. Stage B: The hippocampal 0-waves simultaneously changed to somewhat iriegular and superimposed 10-25 c/s waves. On the other hand, 50 p V , 8 c/s bursts were observed in the EEG from the thalamic lead. At the same stage, 10-13 c/s waves were always observed in the EEG from the skull electrode, but not always in the EEG from cortical leads. It was difficult to find the difference between stages B and A in the spectrum analysis of the hippocampal EEG, since the 2-4 c/s frequency band was similarly increased at both stages. Stage C: The rhythmical wave of 100-250 p V , 6 c/s, the spindle bursts of 70 p V , 11-12 c/s and the bursts of 20 p V , 6-10 c/s appeared in the EEGs from neocortex, caudatus, thalamus and reticular formation. Simultaneously, the hippocampal &waves disappeared gradually ; therefore, the 2-4 c/s frequency band and the fast wave components in the spectrum analysis of the EEG markedly decreased. On the other hand, on the irregular slow waves in the EEG from the amygdala fast waves of 100 p V , 20-30 cjs became superimposed by degrees. References p 147-149

T A B L E I1 ANALYSIS

OFEEGP A T T E R N S

S T A G E S A , BC, A N D D (From Yamamoto, 1959)

F R O M D E P T H E L E C T R O D E S C O R R E S P O N D I N G TO

EEG stage

Application points of electrodes

Frontal skull

I

1 \

20-3oc/s (30-80 p V )

Anterior sigmoid gyrus Caudate nucleus

25-30 (50-80) Irreg. F.W. 20-40 (50) 12 (50) 2- 5 (200) 25-30 (100) Irreg. F.W. (50)

+

Thalamus Hippocampus Amygdala Reticular formation

Level of consciousness =

Irregular; F.W.

=

C

B

A

Occipital skull

Irreg.

O F THE S K U L L L E A D I N T H E ACUTE CAT

10-13C/S (30-150 pV)

5 - 8 ~ 1B.~ (150-250 pV)

\

I

(1 00-250)

8 B. 20 (50 i 10) Irreg. S.W. F. W. (1 50-200) 20-30

6 (100- 150) 11 S. 6-7 (70 30) Irreg. S.W. 8-10 (100-150) 20-30

(100)

(loo)

Irreg. F.W. (1 0-20)

6-10 B. (20)

(50)

+

+

+

+

Rest =

+

6

20-25 (50-100) Irreg. S.W.

Awake Fast wave; S.W.

1

D

Slow wave; B.

=

Burst; s. = Spindle burst.

+

3-6 cis Irreg. S.W. (20&400 p V )

5-8 (1 50) 6 8 (80) 6-10 (100)

3-5 T F.W. (30- 100)

+

6-8 F.W. (100-200) 8-10 (80)

1

\

11-12c/ss. (150-350 pv) 6-8 B. (150-350) 11 s. (200-300) 11 B. (200-300) 1 1 s. (200) Irreg. S.W. 10-15

+

(150)

Irreg. S.W. - 20-30 (100) 11 s. (100-1 50)

Drowsy to light sleep

?

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117

Stage D: The high amplitude spindle bursts of 11-12cjssynchronously appeared in the EEGs from each structure except the amygdala and hippocampus, and 10-15 c/s waves became superimposed on the irregular slow waves in the EEG of the hippocampus. At the same stage, the 8-13 cjs frequency band in the spectrum analysis of the EEG of the thalamus increased markedly. These results are summarized in Table 11. ( 3 ) Relationship between EEG and activity of the nictitating membrane in the acute cat ( a ) Relationship between neocorticaf EEG and activity of the nictitaiing membrane. In general, it is difficult to judge the level of consciousness from the general condition in the acute cat and therefore the relationship between the level of consciousness and the neocortical EEG pattern is yet to be definitely settled. However, as the respiratory rate corresponded with the neocortical EEG pattern, this rate was considered as an indicator of the above relationship (Yamamoto, 1959). Further, contraction of the nictitating membrane was observed during the appearance of the neocortical arousal pattern: on the other hand, relaxation was observed in the drowsy state. For example, the intravenous administration of nikethamide 30 mg/kg usually induced contraction of the nictitating membrane associated with increase of respiratory rate and appearance of neocortical low voltage fast waves, but tactile stimuli failed to induce membrane contraction in 18 % of experiments, in spite oftheappearance ofaneocortical arousal pattern. Spontaneous changes in the neocortical EEG pattern and the nictitating membrane were simultaneously recorded in acute cats. Table 111 shows the relationship between their responses. Contraction of the nictitating membrane accompanying TABLE 111 RELATIONSHIP

BETWEEN

SPONTANEOUS

CHANGE

IN

ELECTRICAL

ACTIVITY O F T H E NEOCORTEX A N D ACTIVITY OF THE N I C T I T A T I N G MEMBRANE I N A C U T E C A T S

(From Yamamoto and Kido, 1961) Chanae in nictitatina membrane (79

CandD (Drowsy) 513

A

(Alert)

A (Alert) C and D + (Drowsy)

67.6

32.3

9.6

90.2

-+

spontaneous appearance of the neocortical arousal pattern was observed in 67.6 % of experimental animals, but not observed in 32.3 %. Correlation of appearance of the neocortical arousal pattern and contraction of the nictitating membrane was recognized in certain cases, but in some cases no changes of the nictitating membrane were observed in spite of the appearance of a neocortical arousal pattern. Therefore, further analysis is required to demonstrate the significance of the nictitating membrane References p . 147-149

118

K. K I D O , K. Y A M A M O T O A N D A. M A T S U S H I T A

as an index of cortical activity. The nictitating membrane is a peripheral effector organ of the sympathetic nervous system, whereas the neocortical EEG reveals the level of consciousness of animals. It is difficult to correlate these two phenomena. At the present time it ha5 not been possible to draw a conclusion about the significance of the nictitating membrane as an index of the level of consciousness. (b) Relationship between changes in neo-, paleo- and archicortical EEGs and the nictitating membrane. Contraction of the nictitating membrane and the hippocampal and neocortical EEG were recorded simultaneously. Hippocampal 8- and neocortical desynchronization were observed when spontaneous contraction of the nictitating membrane occurred. Contraction was not observed when the hippocampal 0-waves were absent, even though the neocortical arousal pattern continued. The nictitating membrane continued to contract when both arousal patterns were present, and it began to dilate as soon as the regularity of the hippocampal EEG was eliminated (Table IV). These facts suggest that contraction of the nictitating memTABLE 1V RELATIONSHIP BETWEEN

EEG

CHANGE A N D ACTIVITY OF T H E

NICTITATlNG MEMBRANE I N A C U T E CATS

(From Yamamoto and Kido, 1961) Stiinululion

Activation Neorortex

Hippacanipus

Change in nictitating nrenibrane

-t

-

-

~

~

Spontaneous EEG change

+ ~ +l + +

Touch Sciatic nerve Posterior hypothalamus Reticular formation

-

-

- 4+

Nikethamide Adrenalin

+ + + +

1 Activation of EEG; - - Unchanged EEG; - = Unchanged nictitating membrane. 1

t

-

t

-

-

i-

f

-t

f

-

+

-1-

Hippocampus

+ - 5 +

I.

Seizure discharge

-

.T

N

+ 4+

=

t _

N

t

?

Contraction of nictitating membrane;

brane is more closely related to appearance of the hippocampal &waves than to that of the neocortical desynchronization pattern. Correlation between nictitating membrane and amygdaloid pattern was not recognized. ( c ) Relationship between electrical stimulation of neo-, paleo- and archicortical activating system and activity of the nictitating membrane. The hippocampal 0-waves

119

B E H A V I O U R A L A N D ELECTROPHYSIOLOGICAL STUDY OF DRUGS R e t i c u l a r f o r m a t i o n lOOc/s 1 m s e t

L AMY

~~~.~~~~

*

L HIP

w+

- -w L A N T SIG

I

A

L ECTSYL

m

m

ECG

l

l

l 10

v

* J

m 1 s e c 50pv

NlCT MEMB

L AMY

LHlP

B

--

I

L ECT SYL

I

ECG

11v

L

1 sec

50pv

NlCT M E M B I -

Fig. 1 . Relationship between EEG activation and contraction of the nictitating membrane elicited by reticular stimulation in the acute cat. (A) The nictitating membrane did not show contraction when only the neocortex was activated by threshold stimulation of thereticular formation. (B) The nictitating membrane markedly contracted when the hippocampal U-waves were induced by higher voltage stimulation of the same structure. (From Yamamoto and Kido, 1961.)

and the responses of the nictitating membrane induced by high frequency stimulation of the midbrain reticular formation were investigated to confirm the relationship between the hippocampal 9-waves and spontaneous contraction of the nictitating membrane. The results are shown i n Fig. 1. The low voltage, fast wave appeared in the neocortical lead immediately after stimulation of the midbrain reticular formation at an intensity of 1 V. However, both the hippocampal EEG and the nictitating membrane were not affected. When stimulating intensity was increased to 1.1 V, contraction of the nictitating membrane accompanied with mydriasis occurred soon after appearance of the hippocampal &waves. The same relationship between the hippocampal &waves and contraction References p .

147-149

TA B L E V ANALYSIS OF

EEG

P A T T E R N S F R O M DEPTH ELECTRODES I N T H E C H R O N I C CAT C O R R E S P O N D I N G TO

6

STATES OF CONSCIOUSNESS

(From Yamamoto, 1959) Application poinls

Level of consciousness

of electrodes

Awake

Excited ~

Frontal skull

4 0 4 5 cis (100 PV) Occipital skull 2040 (50-80) Anterior sigmoid gyrus 40-45 ( 100)

Caudate nucleus Thalamus

20-25 (50-80) 3 4 - F.W. C50)

2&30 CIS (80 PV) 20 (30-50) 20-30 (30-50) 6-8 20 (50) 6 8 20 (50)

+ +

4-6 - F.W. (100)

Hippocampus

4

Amygdala

20-45 (100-150)

8-10

20-30 (20-30)

6-10

Reticular formation

F.W. (200)

-

+ 30

-

Rest

10-13 C I S (30-100 ,uV) 10-14 (30-80) 10-20 (50) 3 4

-

Drowsy to light sleep

--

11-12 c/s. (150-300 PV) 11-12 s. (300) 11-12 s. (100-1 50) 11-12 s. (100-1 50) 11-13 (50-1 00)

5-8 cis (150-200 p V )

(50)

8-12 (30)

6-8 (200) 4-8 ( 150) 12-18 (70) 6-8 - 12 (20)

Irreg. Irreg. Irreg. - F.W. s,w, F.W. s.w, + F . W . S.W. (100-1 50) (100) (30-70) 20-30 4-6 6-8 F.W.

20

+

+

8-12 (20)

8-1 2 (10-20)

8-10 (50)

4-5

11-13

+ F.W.

(1 50) 4-5 - 12

10 B. + 2-4 Irreg. S.W.

(50) Irreg.

=

Irregular; F.W.

=

Fast wave; S.W.

=

Slow wave; B.

=

Burst; s.

=

Spindle burst.

Deep sleep

Activated sleep

F.W. (20-50 pV) 6-8 - F.W. (50) 8-10 F.W. (50) 4-6 (15)

+

4-6 10-12

2-4

3

-

Spike (400)

+ F.W.

-

4-6 20 (80)

+ Sharp W. 12-15 + F.W 1 4 - 10 (300)

+

4-6 F.W. (100-1 50)

B E H A V I O U R A L A N D E L E C T R O P H Y S I O L O G I C A L S T U D Y OF D R U G S

DEEP SLEEP

121

ACTIVATED SLEEP

Fig. 2. The excited state is induced by photic or visual stimulation, or by showing a mouse. The behavioural attention reaction is characteristic in this state. The respiratory rate is 30 per min on average. In the awake state, the behavioural attention reaction is not seen. The cat is only awake and movements of the eyes are feeble. The respiratory rate is 26 per min. In the resting state the cat takes a sitting or ventral posture and its eyes are half closed. The respiratory rate decreases to 22 per min. In the drowsy to light sleep states differentiation is very difficult in the cat. High voltage slow waves and spindle bursts are seen in a mixed form. The respiratory rate is about the same as in the resting state. In the deep sleep state the cat is lying on its side, perfectly relaxed. Respiration is regular and deep and the respiratory rate is 18 per min on average. The behaviour of the cat in the activated sleep state is about the same as in the deep sleep state, except for slight twitches in legs, ears and vibrissae. Sometimes quick eye movements occur. The respiratory rate is irregularly increased. (From Yamamoto, 1959.) Rrferences p . 147-149

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K. K l D O , K . Y A M A M O T O A N D A. M A T S U S H I T A

of the nictitating membrane was observed more markedly with high frequency stimulation of the posterior hypothalamus. The nictitating membrane also slightly contracted at hippocampal stimulation. On the contrary, there was no close relationship between electrical stimulation of the amygdaloid nuclei of the anterior hypothalamus, blocking the hippocampal 0-waves, and contraction of the nictitating membrane. ( d ) Relationship between electrical stimulation of peripheral nerves and artivity of the nictitating membrane. A similar relationship to that mentioned above between the hippocampal EEG pattern and activity of the nictitating membrane was observed when the sciatic and cervical sympathetic nerves were electrically stimulated. The administration of adrenaline (5-10 pg/kg i.v.) also induced contraction of the nictitating membrane accompanied by the appearance of the hippocampal @-waves.

B

A LF

u-\A'w---'-

LF

LORO

L OR0 LGCR

w

LNC

p

w

L G CR L NC

UI,

- LAHTL

I

i HIP

L HIP LAM" LRF

L AMY ~

p Sop v

L RF

2 -

2 sec

Excited

C

LGCR L NC

L T

-

e -

LHlP

LAM"

L F

-__w_.

H

4

L

L

--

D

L THAL

p

L HIP

L4MI

L RF

2 sec Rest

GCR

- v w

L N -C- -+- - -

8-

-

5Op v

Awake

L F L OR0

2 sec

50pv

L RF

2 sec

50,~ii

Drowsy t o light sleep

F

Deep sleep

Activated sleep

Fig. 3. Typical cortical and subcortical EEG patterns in 6 levels of consciousness in the chronic cat. LF - Left frontal skull; L.ORO = Left occipital skull; I..G.CR = Left anterior sigmoid gyrus; I,. N C = Left caudate nucleus; L. THAL = Left thalamus; L. HIP = Left hippocampus; L. AMY = Left amygdala; L. RF = Left reticular formation. (From Yamamoto, 1959.)

BEHAVIOURAL AND ELECTROPHYSIOLOGICALSTUDY OF DRUGS

123

( 4 ) Normal EEG of the chronic cat On the 3rd to 4th day after surgery the cats began to show spontaneous motor activity, and in the EEG the specific wave form of the anaesthetized animal began to disappear. From 7 to 10 days after operation both behaviour and EEG of all operated cats could not be distinguished from those of normal ones. In comparing the behaviour with EEG patterns in the chronic cat, the level of consciousness was divided into 6 stages, i.e. excited, awake, rest, drowsy to light sleep, deep sleep and ‘activated sleep’ (Dement, 1958). Furthermore, we analysed the frequency of characteristic EEG patterns which corresponded to each level of consciousness. The results are shown in Table V and Figs. 2 and 3. The correlation between EEG patterns and level of consciousness is not clear in the acute cat, for we can hardly diagnose the general condition ofthese animals. From the results of our chronic experiment, however, it may be pointed out that in chronic cats the awake, the rest and the drowsy to light sleep states correspond to stages A, B or C and D, respectively. In the acute experiments we could obtain no EEG pattern corresponding with that of the stage of deep sleep in the chronic cat, so that we could not but conclude that the acute cat never attains the level of consciousness corresponding with the period of deep sleep in chronic cats. At the stage of activated sleep in the chronic cat, apparently the EEG patterns led from skull electrodes resembled those of the awake state. Thus it would be impossible to distinguish between the awake and the activated sleep states when leading the EEG only from the skull electrodes. In the EEG led from the hippocampal electrode, however, the 0-waves were markedly seen at the stage of activated sleep while the hippocampal &waves were not clearly seen in the awake state (Fig. 3). Comparing the frequency spectra of the activated sleep and awake states, it may be pointed out that no difference could be discerned in all EEGs except that from the hippocampus, in which the frequency band of 2-4 c/s predominates in the former but that of 4-8 c/s in the latter stage. These results would suggest that the activity of the hippocampus was different in these two stages. In the case of the acute cat, however, the hippocampal &waves significantly appeared at stage A which is considered to be the awake stage so that it is quite impossible to identify this. Although the stage of deep sleep very much resembles the stage of activated sleep as to the behavioural patterns, the respiratory rates are 18 and 33 per min, respectively. This difference seemed to be of use as an index of the level of consciousness. Moreover, twitching of whiskers, ears and limbs seemed to be a characteristic behaviour during the stage of activated sleep. ( 5 ) Neural mechanisms related to activated sleep

‘Activated sleep’ (Dement, 1958) has also been called the ‘paradoxical phase of sleep’ (Jouvet and Michel, 1960), the ‘null stage’ (Blake et al., 1939) or the ‘early morning sleep’ (Gibbs and Gibbs, 1950). This sleeping state usually appears periodically, every 30 to 90 min, throughout the normal sleeping process of man and animals and continues for 1 to 10 min. References p . 147-149

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R . K I D O , K . Y A M A M O T O A N D A. M A T S U S H I T A

Notwithstanding neocortical low voltage fast activity, and particularly hippocampal &waves much clearer than those of any other EEG levels, the animals showed a completely relaxed posture similar to that of the stage of deep sleep. On the other hand, some peripheral phenomena such as disappearance of the EMG of the posterior neck muscles, irregular acceleration of heart rate and respiratory movements, rapid eye movements, facial spasms and twitching movements of the legs, ears and vibrissae were observed corresponding to the EEG and relaxed behaviour in this state. Comparing the behavioural arousal thresholds to noise or direct brain stimulations in activated sleep with those in the state of deep sleep, it was found that the threshold to noise and midbrain reticular stimulation was markedly elevated, whereas, on the contrary, the threshold to posterior hypothalamic stimulation remained unchanged (Yamamoto and Kido, 1962a). Activated sleep was easily induced by administration of drugs lightly inhibiting the reticular formation, such as a small dose of barbiturate, chlorpromazine or meprobamate, or by weak electrical stimulation of the posterior part of the hypothalamus (Yamamoto, 1962). The periodic occurrence and the characteristic EEG pattern of activated sleep were not affected by lesions of the centre median nucleus of the thalamus, the mesencephalic central grey matter or the midbrain reticular formation. However, all EEG characteristics of this state completely disappeared after a localized lesion was made in the posterior part of the hypothalamus, but the periodic occurrence of the phase of EMG-disappearance was unaffected even after this lesion. Furthermore, the characteristic EEG of activated sleep disappeared after mesencephalic transection (chronic ‘cervcau isol6’ preparation). Summarizing the above results, EEG activation in this state seems to be induced via a pathway from the caudal part of the midbrain t o the posterior hypothalamus, but the depth of sleep and the origin ofthe somato-autonomicchanges in this state were not clarified. Appendix I Comparison of normal EEG in cats and dogs The EEGs are roughly similar both in the cat and the dog; however, there are certain differences as follows : (a) Hippocampal injury discharges are significantly generated in cats. On the contrary, these discharges are seldom seen in dogs, especially in the barbiturate anaesthetized condition. Such differences can not be found in the case of injury of the amygdala. (b) In general, the hippocampal &waves in the awake state are more complicated than those in activated sleep (Shimazono et al., 1960; Yamamoto, 1959). This complication is marked in the dog owing to the low amplitude and the superimposition of the fast waves, except in the EEGs led from such specific regions as R:9-10, T: 10-11, V:23-25 in Lim’s atlas. On the other hand, this pattern can be observed from most parts of the cat’s hippocampus. It means that the hippocampal @waves in the dog can only be obtained from a restricted area.

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125

(c) When the dog is i n the excited state, a rather low amplitude but rhythmic hippocampal 0-waves (3-5 cis) are observed for a long time, and sometimes low amplitude, high frequency EEG patterns are introduced in specific areas, as already described. In the cat, this desynchronization of the hippocampal EEG is never seen. Moreover, the high frequency fast waves of the hippocampal &waves in the awaking dog usually disappear and change into rhythmic wave patterns when the dog is in the stage of activated sleep. (d) When the sleeping cat is stimulated by a weak noise, neocortical spindle bursts or high amplitude slow waves change into a desynchronization pattern of low voltage and high frequency, while simultaneously the hippocampal &waves appear. I n the hippocampus of the auditorily stimulated dog, however, the rhythmic &waves have a tendency to appear after 1-2 sec of desynchronization. (e) Neocortical and thalamic levels generate spindle bursts of 12 c/s in the resting cat, whereas in the dog the EEG tends to be irregular. In the cat high amplitude waves of 20 cjs appeared in the neocortical EEG 1-2 sec later than the hippocampal change, and are then transformed into low voltage high frequency waves. (f) Rhythmic waves of 12-14 c/s seen in the resting cat on the neocortical and thalamic level are difficult to observe in the dog under the same conditions, and even if observed the pattern is not so sharp and its duration is short. (g) The voltage of the subcortical and neocortical EEG of the dog in the stage of deep sleep is higher than that of the cat in spite of the fact that the same electrodes are used. Appendix 2

Normal EEG of monkeys Although monkey chairs are generally used for recording the EEG of monkeys, a clear plastic column cage used in recording the EEG of cats and dogs was preferred in our experiments to record the spontaneous EEG and observe the behaviour of monkeys. Some monkeys seemed to fall into a stable sleep lying on the side, but in many monkeys sleep was observed only in the sitting posture and for a short duration. Normal EEGs of monkeys were classified in 7 stages corresponding to the animals’ behaviour. This classification was somewhat different from that of cats and dogs. For example, (a) in monkeys, the hippocampal 0-waves corresponding to desynchronization of the neocortical EEG was seldom observed at the stages of awaking and activated sleep; (b) at the stage of drowsiness, high voltage and irregular slow waves of 50 to 60 p V , 5-6 cjs w g e recorded in the neocortical thalamic leads and also i n the hippocampal leads; (c) at the stage of light sleep the amplitude in all leads was slightly decreased in comparison to that of the drowsy stage, and a spindle burst appeared in the neocortical EEG led from the frontal and temporal areas. The amplitude and duration of these spindle bursts in monkeys were much feebler than those in cats and dogs. Discussion On the normal EEG of the acute cat: The relationship between 4 stages (A, B, C and References p . 147-149

I26

R. K I D O . K . Y A M A M O T O A N D A. M A T S U S H I T A

D) of the cortical EEG led from skull electrodes in the acute cat, classified according to frequency and wave form, and the level of consciousness is inferred from behavioura1 observation and the EEG of the chronic cat as follows: Stage A : Low voltage and fast waves with frequencies of 20-30 c/s: awake state. Stages B and C : 10-13 c/s waves and 5-8 c/s bursts: stage of rest. Stage D: 11-12 c/s spindle bursts: stage of drowsiness to light sleep. It must be mentioned that these 4 stages of the EEG are not always clearly observed in all cases. Especially the appearance of the waves corresponding to stages B or C is relatively unstable. Nakajima (1955) has reported that the cortical and thalamic EEGs obtained from the acute cat with rigidly fixed extremities and a freely movable head shows 20 pVand 15-25 c/s waves in the excited state, 100 pV and 8-1 5 c/s waves in the resting state and 200 pLv and 5-7 cjs waves in a dark environment. These waves correspond to the patterns in stages A, B and C , respectively. Tokizane et al. (1958) reported that in the investigation of the EEG of the neo-, archi- and paleocortex of the curarized cat, neocortical low voltage 20-30 c/s waves appeared in the awake state and an irregular slow wave with a frequency of 2-3 c/s and spindle bursts were seen in light sleep. The neocortical slow waves with frequencies of 2-3 c/s and spindle bursts reported by Tokizane eta!. (1960) might correspond to the pattern in stage D. It has been shown by Derbyshire et ul. (1936) in the EEG study of the acute cat with a freely movable head that a wave form resembling the a-wave i n man is seen. This wave might correspond to the pattern i n stage B. It is a quite noteworthy fact that the 10-13 cjs waves in stage B and the spindle bursts with a frequency of 11-12 c/s in stage D have a tendency to appear predominantly i n the frontal or parietal areas, and the bursts of 5-8 cjs waves in stage C are apt to be localized in the occipital area. Similar results were obtained by Clark and Ward (1945). As there is a possibility that these differences in the cortical EEGs from the various recording areas may cause disagreement on the concept of the normal cortical EEG, sufficient attention must be paid to selecting the recording area of the cortical EEG. The relaxation or contraction of the nictitating membrane and the change in the respiratory rate were employed as the objective indicators to analyse more precisely the relation of the cortical EEG of the acute cat to the level of consciousness. On the normal EEG of the rhronic cat: The correlation between the EEG and 6 levels of consciousness, i.e. excited, awake, rest, drowsy to light sleep, deepsleep and activated sleep, could be obtained by using chronic cats. The frequency of the EEG patterns corresponding with each level of consciousness was analysed. The characteristic wave form during the excited stage was a rhythmic fast wave with frequencies of 40-45 c/s superimposed on the low voltage fast wave, which was recorded only from the monopolar skull and the amygdaloid leads. This pattern seemed to be a particular EEG led from the rhinencephalon. Other investigators (Tokizane, 1958a) have obtained the same results. On the other hand, this pattern was never obtained in the immobilized cat. It may be pointed out that there were 4 specific EEG patterns in the stages of rest and drowsiness to light sleep. As Yokota (1958) and others have stated, the wave of 10-1 3 c/s derived from skull electrodes corresponded with the stage ofrest, and the

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127

spindle bursts of 12-1 3 cis were characteristic during the stage of drowsiness to light sleep. However, it is hard to conclude to which stage the transition period belonged in which bursts with frequencies of 5-8 c/s changed into irregular high voltage slow waves with sharp waves. These bursts were apt to appear mostly in the stage of rest. Hess et al. (1953) have named this burst the peculiar rest rhythm during the stage of rest. These authors also defined that this pattern was the characteristic EEG of the stage of rest. We considered that the irregular high voltage slow wave following the above-mentioned 5-8 c/s burst belonged to the stage of drowsiness to light sleep, since this wave sometimes accompanied the 11-12 c/s spindle burst and the behavioural pattern was that of drowsiness to light sleep. The high voltage wave with a slow frequency of 0.5-2 c/s, resembling the hill wave in the human EEG, was frequently observed in the chronic cat but not in the acute cat even when the experiment was performed over 24 h. There is no other report of which the authors know that describes this hill wave-like pattern observed in the stage of deep sleep. The spike discharge superimposed on the irregular slow wave was seen in the hippocampus and the sharp wave or spike discharges in the amygdala. As these waves are quite similar to the EEG in thiopental-Na anaesthesia it seems reasonable to consider that these patterns represent the lowest level of consciousness. The spike discharge in the amygdala may be explained as the result of synchronization of many afferent impulses from various structures. It has been pointed out that the EEG of the amygdala also shows a pattern that is dissociated from the cortical EEG as in the hippocampus (Kaada and Bruland, 1960), and after administration of nikethamide the transient appearance of the regular slow wave of about 12 c/s is localized in the amygdala. Considering also the observation that the injury discharge a t electrode insertion appeared only in the amygdala and not in the area which has a close anatomical connection to this structure, it may be concluded that the electrophysiological properties of the amygdala are very characteristic. Comparison between EEG patterns of the acute and chronic cat: Comparative analysis of EEG patterns and levels of consciousness in the acute and chronic cat revealed no differences of the essential EEG patterns. In general, however, the voltage of the EEG is higher in the acute than in the chronic cat. In the acute cat, the 10-13 c/s wave and 5-8 cjs burst in the stage of rest and the 11-12 CISspindle burst in the stage of light sleep, particularly the hippocampal 8-waves, appear more sharply and frequently. On the contrary, the 40-45 c/s wave in the stage of excitement and the0.5-3 c/s wave in the stage of deep sleep in the chronic cat were not observed in the acute cat. Also, in the chronic cat the differences between the activated sleep and awake states are easily discerned by observing the behaviour and the EEG patterns. On the other hand, these differences are very difficult to define in the acute cat. The results are summarized in Table VI. The reason why the voltage of the EEG of the acute cat is higher than that of the chronic cat was examined. The construction of recording electrodes was checked on differences in both the acute and chronic cat, but no difference could be discerned. Obviously, the difference of voltage originated in different experimental conditions in the acute and chronic cats. At inspection of histological changes at the site of electrode insertion acute sympReferences p . 147-149

128

R. K I D O , K. Y A M A M O T O A N D A. M A T S U S H I T A

TABLE VI COMPARISON BETWEEN

EEG

PATTERNS OF T H E ‘ACUTF’ A N D T H L ‘CHRONIC‘ CAT

(From Yaniamoto, 1959) ~~

EEG

Acute cat

Clivonic cat

High

High

it

I

-

I 1

?

-1

Hippocampal 0-waves caused by photic stimulation

+

&

Hippocampal @waves caused by tactile stimulation

+i

-I

~

~~

Relative differences in voltage of EEG 10-13 cis waves and 5-8 cis bursts seen in ‘resting’ state Trregular high voltage waves, sharp waves, and 11-12 cis spindle bursts in ‘drowsy to light sleep’ state

0 5-3 c/s waves in ‘deep sleep’ state Difference? between ‘awake’ state and ‘activatcd slcep’ state in EEG

I-+

-

Markedly;

+

-

Moderately; k

=

I \

Slightly; - - None

toms such as appearance of inflammatory cells, edema, necrosis of cells etc. were seen in the acute cat. On the other hand, defence reactions such as encapsulation by fibroblasts and fibrocytes, pseudoneuronophagia, degeneration of ganglia cells with satellitosis and marked neurogliosis were observed in the chronic cat. There were great differences between both conditions. There is yet some risk to conclude that the difference of voltage in the acute and chronic cat is due to the differences of the histological changes. However, a constant and stable normal EEG can be obtained 1 week after operation (Yamamoto, 1959; Yokota, 1958). Fischer et al. (1957) also reported that histological damage caused by electrode implantation was repaired by neuroglia 1 week after operation. In considering these results, it is reasonable to assume that the difference of voltage between the acute and chronic cat depends upon different histological changes. The reason why external stimuli cause marked hippocampal &waves in the acute cat may be found in the fact that hippocampus and amygdala are sensitive to mechanical stimuli and seizure discharges are easily seen (Tokizane, 1958a) in the leads from these structures. The same tendency is not only seen in the hippocampus but also in the EEG from all other derivations; this fact is related to the potent flow of afferent impulses from the pain receptor (Tokizane, 1958b). In our experiments, the voltage was lower after injection of D-tubocurarine and therefore the authors support Tokizane’s theory. Summary 1 . EEG patterns in acute cats were classified into stages A, B, C and D according to characteristic frequencies and wave forms. Typical EEG patterns during stage A consisted of 30-80 p V , 20-30 c/s waves and hippocampal &waves of 200 p V ,

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129

2-5 cjs. In stage B 30-150 p V , 10-13 c/s waves appeared in the frontal and parietal leads, but hippocampal arousal disappeared. In stage C 150-250 ,uV, 5-8 c/s bursts appeared predominantly in the occipital lead. In stage D 200-400 ,uV irregular high voltage waves and furthermore 150-350 pV, 11-12 c/s spindle bursts appeared in all leads except those from the hippocampus and amygdala. 2. In order to judge the level of consciousness in the acute cat, the relationship between EEG and contraction of the nictitating membrane was examined. The results suggest that the contraction of the nictitating membrane is more closely correlated to the appearance of the hippocampal &waves than to that of the neocoitical desynchronization pattern. 3. According to EEG and behaviour, the levels of consciousness of chronic cats were classified into 6 states, that is: excited, awake, rest, drowsy to light sleep, deep sleep and ‘activated sleep’. In the excited state, rhythmical waves of 50-100 p V , 40-50 c/s appeared in all monopolar skull and amygdala leads, furthermore the hippocampal &waves of 200 p V , 4-5 cjs were marked. Patterns of the awake state were the same as those of stage A in the acute cat, but hippocampal @waves were not so marked. The patterns of the state of rest were the same as those of stages B and C and the patterns of the state of drowsiness to light sleep were the same as those of stage D in the acute cat. In the state of deep sleep irregular slow waves of 200-400 p V , 0.5-2 c/s appeared in the skull, cortical and subcortical leads, spikes in the hippocampus and sharp waves in the amygdala. In the state of activated sleep, the behaviour of the cat was about the same as in the state of deep sleep except for slight twitches in legs, ears and vibrissae, but EEG patterns resembledthose of the awake state, the hippocampal 8-waves being particularly marked. 4. No essential difference between the EEG patterns of acute and chronic cats was observed, but there were some interesting findings. The voltage of the EEG was generally higher in acute than in chronic cats. Further, in acute cats a more marked appearance was observed of 5-8 c/s bursts in the state of rest and 11-12 c/s spindle bursts in the state of drowsiness to light sleep, particularly hippocampal &waves caused by external stimulation. In fixed cats, deep sleep patterns were not found even in overnight experiments. 5. Normal EEGs obtained in various states of consciousness in the chronic dog and monkey were compared with those of the chronic cat. P A R T 11. B E H A V I O U R A L A N D

ELECTROENCEPHALOGRAPHIC ANALYSIS OF

C E N T R A L N E R V O U S SYSTEM D E P R E S S A N T S I N A N I M A L E X P E R I M E N T S

On the basis of the observation of the normal EEG of the cat, CNS depressants were analysed behaviourally and electroencephalographically in the cat with permanently implanted electrodes. Furthermore, a comparative analysis of the effects of CNS depressants in cats, dogs and monkeys was made.

References p . 147-149

130

R . K I D O , K . Y A M A M O T O A N D A. M A T S U S H I T A

A . Analysis of’ centrd nervous system depressants in cafs with pernianently implanted electrodes Introduction The purpose of the present study was the comparison of central nervous system depressants such as chlorpromazine, reserpine, meprobamate, chlordiazepoxide and barbiturates, both electroencephalographically and behaviourally, using cats with permanently implanted electrodes. TABLE VII CNS D E P R E S S A N T (mg/kg (From Yamamoto and Kido, 1962b)

D O S A G E L E V ~ L SO F E A C H

Chlorpromazine

Small dose Middlc dose Large dose

0.2 1-5 15

Reserpine 0.03 0.1-0.3

I .5

I.V)

Meprobamate

PhenobarDital-Na

Pentoharbital-Na

6 30-60 I20

6 30-60 120

3 9-18 30

Morphine 1 3 10

Melhods Experiments were performed using 20 chronic cats with a cross-over design in Latin square form of 3 weeks’ interval. The implantment technique and sites of electrode insertion in the chronic cat have already been described. The dosage of each intravenously administered drug was classified into three levels according to behavioural effects as shown in Table VIL. In order to analyse the site of action of the drugs, their effects were examined on the EEG arousal reaction and the behavioural attention reaction following various external stimulations and also on behavioural changes elicited by electrical stimulation of various areas of the brain such as anterior and posterior part of the hypothalamus, the midbrain reticular formation and the amygdala.

Results ( 1 ) Chlorpromazine After intravenous injection of chlorpromazine (0.2, 1-5, 15 mg/kg), the cat took a drowsy to light-sleeping posture. Characteristic EEG patterns were irregular slow waves in the neocortex and low voltage, fast waves in the amygdala (Fig. 4A). On the other hand, in spite of the arousal waves that were seen in the neocortex, hippocampal 0-waves were completely blocked (Fig. 4B). That is, a ‘dissociation’ of EEG patterns was induced (Tokizane et al., 1960) between the neocortex and the hippocampus. Narcosis was never seen even with large doses of clilorpromazine, and the prevailing level of consciousness was a slate of drowsiness or light sleep. However, the EEG arousal reaction and the behavioural attention reaction almost disappeared.

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131

After the injection of chlorpromazine (1-5 mg/kg), cats which had assumed a sleeping posture suddenly jumped up and scratched the cage or bit the lead wire. This abnormal behaviour, which was called ‘rage-like behaviour’ (Kido and Yamamoto, 1962) and resembled the complex behaviour of ‘sham rage’ and ‘chewing response’. was repeatedly seen in almost all cats treated with chlorpromazine within about 6 h after the injection. In order to analyse this behaviour, stimulation experiments were performed in which the threshold elevations were compared. As shown in Table VIII, the thresholds of behavioural changes caused by anterior hypothalamic and reticular stimulation were elevated after injection of chlorpromazine. On the contrary, the thresholds of ‘sham rage’ caused by posterior hypothalamic stimulation and ‘chewing response’ caused by amygdaloid stimulation were not affected. This unevenness of the threshold elevation could be one of the mechanisms of the ‘rage-like behaviour’ caused by administration of chlorpromazine. ( 2 ) Reserpine Reserpine (0.03,O.l-0.3, 1.5 mg/kg) caused rigidity of the skeletal muscles, increased respiration rate, ptosis, myosis and diarrhoea. The ataxia reached a peak within 24-48 h and continued for 100 h. Rhythmical slow waves of about 12 c/s were continuously seen in the neocortex and the thalamus, while the amygdala and the hippocampus showed an arousal pattern. Within 24-48 h after administration of reserpine, in spite of the arousal pattern in the neocortex, the limbic system, especially the amygdala, showed a deep sleep-like pattern and the animal exhibited a sedate behaviour. At this time, the normal EEG arousal reaction of the neocortex and the ‘arousal pattern in lower level’ (Tokizane, 1958b) of the amygdala were observed, but the behavioural attention reaction disappeared.

( 3 ) Meprobamate Meprobamate (6, 30-60, 120 mg/kg) caused the appearance of rhythmical 14 to 20 cjs waves in the neocortex and the thalamus. At a higher dose of meprobamate spike discharges were seen in the amygdala and characteristic 25 c/s high voltage waves in the hippocampus; the behaviour showed drowsiness to deep sleep. The behavioural attention reaction remained normal even with larger doses of meprobamate. ( 4 ) Chlordiazepoxide Within 60 to 120 mill after oral administration of chlordiazepoxide, cats continuously maintained an awake posture. At this time, characteristic rhythmic waves in neocortical and thalamic leads were seen and later a drowsy-like pattern was observed in the neocortex corresponding to hippocampal fast waves and behavioural sleep. Narcosis was never seen at large doses of the drug (50-60 mg/kg, per 0s).

( 5 ) Phenobarbital-Na Phenobarbital-Na (6, 30-60, 120 mg/kg) caused sedation, sleep and narcosis. High voltage slow waves were observed in the neocortex and the thalamus, multiple spikes References p . 147-149

L CM

ALERT I

w

P 3

LAMY

v -

L HIP

h -

L ANT SIG P

L ECT SY L

x

0 “0

L LAT u

-

?

;

B

e

280 rnin

0

2 I

I

I

Fig. 4. EEG patterns of a chronic cat before and after administration of chlorpromazine. The upper two pictures show normal alert and drowsy patterns. (A) 64 min after administration of 5 mg/kg of chlorpromazine the cat took a relaxed posture; irregular slow waves appeared in the sensory areas of the neocortex and in the centre median nucleus of the thalamus and a desynchronized pattern in the amygdala. (B) 280 min after drug administration, the cat still maintained the same posture; although the arousal pattern was seen in the neocortex, the thalamus and the amygdala, blocking of the hippocampal &waves were observed. L. CM = Left centre median nucleus of the thalamus: L. AMY = Amygdala; L. HIP = Hippocampus; L. ANT. SIG = Anterior sigmoid gyrus; L. ECT. SYL = Ectosylvian gyrus; L. LAT = Lateral gyrus. (From Kid0 and Yamamoto, 1962b.)

W

m

?

r

s

T A B L E VIII EFFECT OF

CHLORPROMAZINE,

MEPROBAMATE AND

PHENOBARBITAL-Na

O N V A R I O U S BEHAVIOURAL C H A N G E S ELICITED BY

RETICULAR,

0

d

HYPOTHALAMIC A N D A M Y G D A L O I D STIMULATION I N C H R O N I C CATS

(From Kido and Yamamoto, 1962) Parameters

Behaviour

Chlorpromazine 3-5 mglkg i.v. (%)

Meprobamate 30 mglkg i.v. (%)

Phenobarbital-Na 30 rngikg i.v. (%)

+ 80

+ 50

67

Anterior hypothalamus

100 CIS 1 msec 2.5-7.0 V

M ydriasis Olfactory response Searching response

Posterior hypothalamus

100 cis 1 msec

Searching response

- 6

+ 46

+ 41

2.0-7.0 V

Sham rage

- 4

65

+ 60

100 cis 1 msec 2.0-3.5 V

Mydriasis Piloerection Somatic movement

+ 38

t 32

+ 75

40 CIS 3 msec 1.0-5.0 V

Olfactory response Chewing response Salivation

- 1

i30

+ 63

Reticular formation

Amygdala

- _- 0-25 %, insignificant elevation of stimulation threshold

+ = over 26%. significant elevation of stimulation threshold

m r m 0

134

R . K I D O . K. Y A M A M O T O A N D A. M A T S U S H I T A

in the amygdala and low voltage fast waves in the hippocampus. Disappearance of the EEG arousal reaction usually progressed in parallel with that of the behavioural attention reactions, and the ‘arousal pattern in lower level’ was sometimes observed in the neocortex and the thalamus.

Discussion Tokizane et a/. (1960) clarified the influence of the ‘hypothalamic activating systems’ on the paleo- and archicortex. From this point of view, the results obtained with chlorpromazine and reserpine seem to suggest that each drug influenced both activating systems. Kawamura ef al. (1961) demonstrated electroencephalographically that in acute cats chlorpromazine depressed the hypothalamic activating system more than the reticular activating system. Yokota (1959, in chronic cats) and Monnier (1957, in rabbits) also showed the depressive effect of chlorpromazine on the reticular activating system. On the other hand, since desynchronization of the amygdaloid lead and blocking of the hippocampal &waves were usually obtained as a result of activation of the preoptic region (Tokizane et al., 1960) or the septum, one of the effects of chlorpromazine might be activation of the inhibitory area on the hippocampal 0-waves, as described by Preston (1956). Also, the unevenness in the elevation of the stimulation thresholds in the central nervous system by chlorpromazine administration was presumed to be a possible mechanism of ‘rage-like behaviour’. Kaada and Bruland (1960) observed that the stimulation threshold of the posterior hypothalamus was not affected by chlorpromazine in the cat. The neocortical and thalamic slow waves caused by reserpine might suggest an effect of the drug on the neocortical system as described by Monnier (1957). On the other hand, behavioural sedateness and electroencephalographical deep sleep-like patterns in the amygdala, dissociated from the neocortical arousal pattern later, seem to suggest that the limbic system is one of the sites of action of the drug. Kikuchi (1961) concluded from electroencephalographical observations that in reserpine treated rabbits the site of action was in areas other than the neocortical system. After administration of meprobamate a characteristic EEG pattern appeared in all leads. However, a specific effect of the drug on the thalamus, as shown by Hendley et al. (1957), was not noticed. The EEG change in the limbic system, the results described in Table VIII and Randall’s description ( I 961) might suggest that the site of action of meprobamate is not only to be found in the neocortex but also in the limbic system. Evident EEG changes caused by phenobarbital-Na were seen in the neocortical and thalamic leads. Behaviourai (Randall, 1961; also as shown in Table VIII) and electrographical confirmation was obtained that these changes are due to decreased functioning of the reticular activating system. As mentioned above, marked differences between tranquilizers and barbiturates were recognized and meprobamate seems to occupy an intermediate position between chlorpromazine and phenobarbital-Na.

B E H A V I O U R A L A N D E L E C T R O P H Y S I O L O G I C A LS T U D Y O F D R U G S

135

Summary

Experiments were performed to analyse the characteristic effects of tranquilizers and barbiturates both electroencephalographically and behaviourally, using cats with permanently implanted electrodes. In cats treated with chlorpromazine and reserpine, such characteristics of EEG and behaviour were observed as a moderate fall in neocortical and thalamic activity, a marked fall in amygdaloid and hippocampal activity and dissociation of the latter from the neocortical activity, postural unconcernedness to the circumstances, changes in various autonomic functions and nonhypnotic action by a large dose of the drug. The ‘rage-like behaviour’ caused by chlorpromazine was also analysed. Jn phenobarbitalNa treatment, on the contrary, the characteristic EEG changes observed were mostly a fall in neocortical and thalamic activities with anesthetization. Meprobamate seems to have an effect intermediate between those of chlorpromazine and phenobarbital-Na. R. A comparative analysis of behavioural and Plectraencephalographic changes caused by C N S depressants in animal experiments

The purpose of the present investigation is to compare functional states induced by CNS depressants with definite electroencephalographic patterns and behaviour in the cat, dog and monkey. Our stereotaxic technique for stimulating and deriving the electroencephalograms of cortical or subcortical structures in the unanaesthetized (chronic) or immobilized (acute) cat, dog and monkey has already been described. In order to analyse the mode of action of the drugs, the effects were examined on the electroencephalographic and behavioural changes elicited by electrical stimulation of various areas of the brain such as anterior and posterior part of the hypothalamus, midbrain reticular formation, central grey matter, septum, amygdala, etc. Stimuli of various frequencies, durations and voltages were applied according to the structure. (1) Differences in electroencephalographic patterns of the acute and chronic cat: After the administration of reserpine, meprobamate or barbiturate, no differences in electroencephalographic patterns between acute and chronic cats were observed. However, after chlordiazepoxide or morphine administration the differences were obvious. In chronic cats, from 20-40 min following the oral administration of chlordiazepoxide 20 mg/kg, symptoms of excitation such as grooming, trying to escape from the cage and increase of friendly behaviour were observed. At this stage 10-14 cjs rhythmic waves were recorded in the neocortical and thalamic leads and 4-5 c/s rhythmic waves i n the hippocampal leads (hippocampal &waves). From 150-200 min after drug administration the cat became sedated but a continuous deep sleep posture was never seen. At this time, characteristic 20-30 c/s high voltage waves appeared in the hippocampal lead. However, judged by EEG patterns the level of consciousness remained that of the stage of light sleep (Fig. 5A). After oral administration of chlordiazepoxide, the EEG patterns in acute cats resembled those of the chronic cat from 30-100 min, but after this stage the patterns changed to that of the stage of deep sleep (Fig. 5B). References p . 147-149

136

R. K I D O , K. Y A M A M O T O A N D BEFORE LCM

ALERT

A. M A T S U S H I T A

DROWSY

-

A f t e r chlordiazepoxide 20 mg/kg p e r 05 81 min 197 min

Fig. 5 . Comparison of EEG patterns in the acute (A) and chronic (B) cat before and after oral administration of chlordiazepoxide 20 mg/kg. (From Yamamoto and Kido, 1964.)

After morphine administration, these differences were more evident, when slow waves and spindle bursts were continuously seen in the neocortical leads of the acute cat, whereas in chronic cats desynchronization patterns corresponding with behavioural alertness were consistently seen in neocortical leads (Yamamoto ct al., 1961). EEG recording of the acute animals was carried out under hard conditions of electrodeinsertionwithout anaesthesia, immobilization by muscle relaxant and artificial respiration. The experiments on cats treated with chlordiazepoxide or morphine need not be carried out under these hard conditions, because chlordiazepoxide inhibits the EEG arousal reaction induced by stimulation of the central grey matter which is a part of the pathway of visceral afferent impulses, and morphine is a powerful analgesic. Accordingly, slow waves and spindle bursts might be continuously seen in the acute cat, while desynchronization patterns are lasting in the chronic cat. These findings

BEHAVIOURAL AND ELECTKOPHYSIOLOGICAL STUDY OF DRUGS

137

show the danger of misjudging the levels of consciousness if only the EEG patterns of the acute cat are used as the criteria. (2) Difesences in EEG and hehaviousal sespcnseAs due to species specificity. No differences in EEG and behaviour between cats, dogs and monkeys were observed after reserpine, meprobamate or barbiturate administration. A

B

Fig. 6. Species specificity in behaviour after intravenous injection of morphine. A After morphine 5 mg/kg i.v. (From Yamamoto and Kido, .1964.) References p . 147-149

=

control; B =

138

R. K I D O , K . Y A M A M O T O A N D A . M A T S U S H I T A 6'0

0

Narcosis Activated sleep Deepsleep Light sleep

-

-

110

CAT

nnnnT n n n n

-

Awake

160

240(din)

JMorphine 5 m g / k g I.V.

a

J

DOG

nn [

MONKEY

nnn

I

F l M o r p h i n e 5 r n g / k g 1.V

Fig. 7. Species behavioural and EEG changes induced by intravenous injection of morphine. The cat shows a continuously excited state. In the dog narcosis is seen. In the monkey narcosis is not observed but aggressive behaviour is strongly inhibited. (From Yamarnoto and Kido, 1964.)

However, chlorpromazine caused continuous sleeping behaviour in dogs and cats, and in the latter animals sometimes a paroxysmal excitation behaviour, that is a 'ragelike behaviour'. On the other hand, a far smaller dose of the drug (1-2 mg/kg) was sufficient to cause continuous deep sleep in monkeys. This species specificity of the drug effects was also clearly observed in the EEG. In cats, notwithstanding the neocortical desynchronization, chlorpromazine caused a repetition of drowsy and arousal patterns and blocking of hippocampal 8-waves. In dogs, sometimes the deep sleep pattern was observed; furthermore, the hippocainpal &waves clearly appear to be dissociated from the neocortical slow activity. On the contrary, in monkeys high voltage slow activities were repeatedly seen after injection of chlorpromazine. After administration of morphine cats show acontinuous state of arousal, dogs show narcosis and monkeys show responses intermediate between those of cats and dogs, in both the EEG and behaviour (Figs. 6 and 7). Electroencephalographic and behavioura1 seizure discharge caused by larger dose of morphine (over 10 mg/kg i.v.) was sometimes observed in cats, on the contrary, it was never seen in dogs and monkeys. Species specific effects of morphine in cats and dogs were analysed by comparing the threshold changes of the arousal reaction on stimulation of the neo-, paleo- and archicortical activation systems. The threshold of the activating system from midbrain reticular formation to neocortex was not changed in the cat, but in the dog the threshold was markedly elevated (Table IX). This difference could be one of the reasons why species specific effects were seen. (3) Association and dissociation between EEC and behavieur: After lesions of the mesencephalic reticular formation or the posterior hypothalamus, the same tendency

139

B E H A V I O U R A L A N D ELECTROPHYSIOLOGICAL STUDY OF DRUGS

T A B L E IX COMPARISON O F T H R E S H O L D C H A N G E S I N THE NEO-, PALEO- A N D ARCHICORTICAL ACTIVATI N G SYSTEM I N T H E A C U T E C A T A N D D O G AFTER I N J E C T I O N O F M O R P H I N E

(From Yamamoto and Kido, 1962b)

Parameters

Car (5-6 mglkg i.v.)

Stimulation-response

Dog (3-6 mglkg i.v.) ( %I

( %)

Hypothalamic activating system

Ant. hypothalamus-amygdala Ant. hypothalamus-hippocampus Post. hypothalamus-hippocampus Post. hypothalamus-ant. sig. gyrus Centre median nucleus-ant. sig. gyms Reticular formation-ant. sig. gyrus Centre median nucleus-ant. sig. gyrus Sciatic nerve-ant. sig. gyrus Splanchnic nerve-hippocampus ant. sig. gyrus

Reticular activating system Recruiting response Peripheral nerve

-

+ t + + + +

++

125 187 139 139 134 122 128 169 205

- 124 160 137 134 188 173

+ + + + + + 160 + 175

- = 95-125%, no change in threshold; 4-= 126-200%, moderate elevation in threshold; > 200%, marked elevation in threshold.

++ =

is seen. Tokizane et al. (1960) reported on an activating system from the posterior hypothalamus to the neocortex. After lesions of the posterior hypothalamus the cat showed coma, hypothermia and respiratory inhibition. At the same time spike and slow waves are seen in neocortical, hippocampal and amygdaloid leads. After pinching the paw, the lower level arousal pattern was seen in all leads. This lower level arousal pattern appearing after pinching the paw could never be induced in cats in whom the mesencephalic reticular formation had been destroyed. However, in these cats with lesions in the mesencephalic reticular formation or the posterior hypothalamus, EEG patterns were associated with behaviour. After administration of reserpine or morphine the EEG corresponds with behaviour. TABLE X EFFECTS OF

CNS

DEPRESSANTS O N

EEG

AROUSAL REACTION I N T H E NEO-, PALEO- A N D

A R C H I C O R T I C A L SYSTEM A N D S E I Z U R E D I S C H A R G E S I N C H R O N I C C A T S

(From Yarnamoto and Kido, 1964) Morphine

mglkg

(i.v.) ( %)

Anterior hypothalamus Posterior hypothalamus Reticular formation Central grey matter Septum Am ygdala -_

~

Amygdala - 125 Hippocampus 139 Neocortex - 122 Hippocampus 135 Seizure discharge - 100 Seizure discharge - 110

3

-+ -+ -+ -+ -+

90-125%, no change in threshold;

References p. 147-149

+ +

+

=

Chlorpro-

Meprobamate 3 mglkg (i.v.) 30 mg/kg ( %)

+ 160 -1- 185 + 141 + 133 - 98 - 99

(i.v.) ( %>

Clordiazepoxide 20 mglkg (per os) ( %)

- 113 - 112 137 144 - 100 140

- 98 - 112 - 114 141 - 112 - 100

+ + +

126-200%, moderate elevation in threshold.

+

140

R. K I D O , K. Y A M A M O T O A N D

A. M A T S U S H I T A

TABLE XI EFFECTS O F

CNS

DEPKESSANTS O N REHAVIOUR C H A N G E S ELICITED B Y STIMULATION OF VARIOUS BRAIN STRUCTURES I N CHRONIC CATS

(From Yamamoto and Kido, 1962)

?

i180

-t 150

+ 146

+ 143*

99

- 106 - 104

-t 146

- 106

- 115

+ 138

+ 132

+ 100

+ -+ 205*

- 117

- 101 - 108

- 108

+ 183

- 100 I 159

- 100

- 105

- 105

- 112

Anterior hypothalamus

Mydriasis, Sniffing, Searching response Posterior ( Searching hypothalamus response Rage Reticular formation Piloerection, Mydriasis9 Somatic movement Central grey Mydriasis, matter Piloerection, Head-turning Hissing Sniffing, Septum Salivation, Searching response, Feeding response Amygdala

I I

-

+ 165

+ 135

Ii i

i I

Feeding response

+ 130 90-125 z, no change in threshold; +

- 120

- 107

* Escape (running and jumping) elevation of threshold; = over 200%, marked elevation of threshold.

++

- 110

126-200%, moderate

On the other hand, the cat with pretrigeminal midpontine tiansection showed a behavioural coma but the desynchronization pattern was dominant in neocortical leads and slow waves remained in the stage of resting to light sleep. Both in normal activated sleep and in cats with reticular lesions in the caudal brain stem, the animals show a sleep-like posture, while the EEG shows activation-like patterns. This kind of dissociation between EEG and behaviour is also observed after administration of some CNS depressants. For example, under deep ether anaesthesia, neocortical activities showed the desynchronization pattern and hippocampal lead showed evident @waves. Chlorpromazine markedly elevated the stimulation threshold of the posterior hypothalamus and the central grey matter to the hippocampus electroencephalographically. On the contrary, thresholds of sham rage caused by posterior hypothalamus and hissing caused by central grey matter stimulation are not changed by the same dose of drugs (Tables X and XI). Chlordiazepoxide and meprobamate

BEHAVIOURAL AND ELECTROPHYSIOLOGICAL STUDY OF DRUGS

141

also do not influence the threshold of EEG arousal reaction induced by hypothalamic stimulation; these drugs only elevate the stimulation threshold of the reticular activating system while sham rage and olfactory response are inhibited. Summary

In animals with needle electrodes implanted into the CNS the following comparative effects of various drugs were observed. 1. Differences between electroencephalographic patterns of the unanaesthetized (chronic) and immobilized (acute) cat, No differences were observed after administration of reserpine, meprobamate or barbiturate. With chlordiazepoxide, deep sleep patterns were seen in the acute cat, but never in the chronic cat. With morphine these differences were still more evident. 2. Species differences in electroencephalographic and behavioural responses were observed in animals treated with chlorpromazine and morphine. 3. Discrepancies between EEG and behaviour were observed in cats with destruction of the pontine reticular formation. This kind of discrepancies between EEG and behaviour is also observed in cats treated with ether, morphine, chlorpromazine, chlordiazepoxide, or meprobamate. P A R T 111. P H A R M A C O L O G I C A L A N A L Y S I S O F A T A X I A

Introduction

Behavioural observation, the first procedure to be undertaken in pharmacological studies of a new drug is the simplest and yet the most important method because much significant information is obtained and many suggestions present themselves that are useful for determining the direction of the analysis to follow. The observer’s attention is mainly directed to the changes in motor function and level of consciousness; an interesting finding in the latter is often analyzed further by an electroencephalographic method in the ensuing experiment, but in most cases a significant syndrome in the former is only dealt with by a description in customary words, such as ataxia, tremor, convulsion, rigidity, etc. During the last decade, introduction of the concept of a y-motor regulation (Granit, 1955), discovery of the functional differentiation of the a-motoneurone (Granit et al., 1956) and establishment of spinal synaptic mechanisms (Eccles, 1964)have been added to our knowledge relating to the motor function. Therefore, if these electrophysiological findings are applied to pharmacological study to clarify a drug action bringing about a serious motor syndrome in the animal, it may become possible to obtain data which elucidate a mechanism not clearly explained up to the present, and to develop a new conception about the pharmacological property. The purpose of the present report is to show an example which proves the possibility described above. In this laboratory, the observation was made that 2-(3-dimethylaminopropyl)1, 3, 3a, 4, 9, 9a-hexahydro-4,9-o-benzeno-2H-benz[f]isoindole dimethiodide (MI65-S) does not only have a relatively potent ganglionic blocking action, but also References p. 147-149

I42

K. K I D O , K . Y A M A M O T O A N D A. M A T S U S H I T A

brings about a long-lasting ataxic behaviour in mammals (Matsushita, 1964). Moreover, this compound produces a marked decrease in the frequency of muscle spindle discharges, and its potent depressant effect on muscle spindle activity may be the main mechanism of ataxic behaviour. The de-efferented muscle spindle is attacked by this compound, so that the site of action is peripheral (Matsushita, 1964; Matsushita et al., 1965). It may be concluded that MI-65-S is a drug belonging to a new category of muscle relaxants.

Methods Mainly cats and dogs were used as experimental animals. Cats were tracheotomized under ether inhalation, fixed on a stereotaxic instrument and decerebrated intercollicularly by suction. Laminectomy was performed at lower lumbar and upper sacral levels. To record the afferent impulses from the anti-gravity extensor muscles in the hind limbs and the cutaneous touch receptor, the ventral and dorsal roots on both sides were cut and the dorsal filaments of L7 or S1 were split into a functional single fibre and placed on the silver wire electrodes. For studying drug effects on the spinal reflex activities, a square wave stimulation was applied on the tibial nerve and the spinal reflex discharges were recorded from L7 or S1 ventral roots. In order to study the action on the neuromuscular junction, electrical stimulation was applied to the peripheral end of the tibial nerve and the contraction of the gastrocnemius muscle was recorded by a mechanical device or by an electromyographic method. Whether the muscle stiffness produced by decerebration was reduced by MI-65-S was studied on two types of rigidity, a- and y-rigidity. When the ataxic behaviour reached its maximum in the cat, intercollicular decerebration with additional anterior lobectomy of the cerebellum, or anemic decerebration by ligation of both carotid arteries and the basilar artery were performed. The rigidity appearing in the m. triceps brachii was measured by an electromyographic method. Sequential discharges of single neuromuscular units were recorded from the plantar muscle of the dog in the standing posture with two thin steel electrodes insulated except at the very tip. According to Tokizane’s method (Tokizane, 1955), the mean value (7) and the standard deviation (s) of spike-to-spike intervals were calculated on the sequence of more than 50 impulses of a single unit, the standard deviation of each unit was plotted against the mean value on a graph and the distribution of t - s points was examined.

Results The motor syndrome developing in the cat after intravenous administration of M1-654 3 to 5 mg/kg is as follows: It usually took about 30-60 min for the first sign of locomotor disturbance to appear, that is walking with tottering steps. After 90-120 min, reduction of the muscle tone became so marked in the anti-gravity muscles that the animal could no longer support its body with its extremities and crawled on the floor. In this state, however, mechanical stimulation applied to the skin caused the flexion reflex to occur in almost normal pattern and voluntary muscle contraction

BEHAVIOURAL A N D ELECTROPHYSIOLOGICAL STUDY OF DRUGS

143

was frequently observed. In higher doses, transient and weak ataxia, which disappeared completely within 10-30 min, preceded the strong and long-lasting ataxia. This dual pattern of ataxia is conspicuous in rodents. The hypothesis that a blocking action on the neuromuscular junction might be the cause of ataxia was first neglected (Matsushita, 1964). No significant changes in neuromuscular transmission were observed when the dosage of 3 mg/kg, sufficient to produce ataxia, was injected. However, a remarkable blocking effect was observed at 10 to 20 mg/kg and complete blocking was seen with the dosage of 30 mg/kg. Recovery occurred within 15-30 min. Granting that the first phase of the dual pattern of ataxia might be related to this curare-like action, the following strong ataxia could not be explained by it. Another known type of muscle relaxant is the series represented by myanesin. The site of action is said to be the central nervous system and drugs of this series selectively reduce the polysynaptic activities (Taverner, 1952). However, MI-65-S Failed to act on the spinal reflex discharges, even at the dosage of 10 mg/kg (Matsushita, 1964). Since possible alternative explanations applicable to the mode of action of muscle relaxants could not be accepted in this case, it seemed reasonable to consider that MI-65-S may have a hitherto unknown pharmacological action. Our attention was then turned to the y-system, which plays a very important role in the maintenance of

L

I SEC

D

I

1

-

1

-

c _

lSEC

J

3 SEC

Fig. 8. Effect of MI-65-S on the muscle spindle and cutaneous afferent discharges. A-D show the decrease in muscle spindle discharges of the m. gastrocnemius of the cat when constantly stretched. A = control response; B, C, and D = responses a t 20, 36 and 46 min respectively after intravenous administration of 3 mg/kg of MI-653. E-J indicate that the static phase, produced by applying a periodic stretch for 3 sec on the de-efferented gastrocnemius muscle, is more susceptible to the action of MI-65-S than the dynamic phase. E = control response. F-J = records obtained 5,3 I , 62, 180 and 31 5 min after intravenous administration of 3 mg/kg of MI-65-S. K-M show that the cutaneous touch receptor was not affected by MI-656. The muscle spindle discharges from the constantly stretched gastrocnemius muscle and the impulses from the cutaneous touch receptors in the skin of the hind limbs are simultaneously recorded on a pen-writing oscillograph through a pulse-modulator. Initiation of the impulses from the touch receptor is indicated by the horizontal lines. K = control response. L and M = 35 and 60 min after drug administration. (E-J from Matsushita, 1964.) References p . 147-149

144

R . K I D O , K . Y A M A M O T O A N D A. M A T S U S H I ' I ' A

TABLE XI1 T H F U t P K E S S I V k EFFECT OF M I - 6 5 - S O N T H E M U S C L E S P I N D L E D I S C H A R G E S The muscle was de-efferented and continuously stretched at a constant length. (From Matsushita, 1964)

Dose (i.v.) (wlg/kg)

1.o 3.0

5.0

-

Frequency of muscle spindle discharges (cis)

-~ Control

I0

30

60

90

120

150

20 17 10 22 38 20 15 18 24 39

16

17 7 15 32 20 6 6 12 35

13 10 0 4

20 8 0 2 10 12 0 0 5 8

20 8 0 0

9 0 2

13

12 0 0 7 3

12 0 0 5 0

20 15 2 4

5 12

.-

.~

180

210

240

3

5

5

5

12 0

15 0 0 7

16

18

0 5

8

skeletal muscle tone. A series of impulses of the de-efferented muscle spindle was elicited with a fine regularity by applying a continuous and constant stretch to the muscle studied. As shown in Fig. 8A-D, reduction of the muscle spindle discharges was initiated within 30 min by a dosage of 3 mg/kg. When the initial frequency was only about 10 c/s, the muscle receptor often ceased to fire. These results are summarized in Table XII. Fig. 8E--J indicates that the static phase, produced by applying a periodic stretch to the usually relaxed muscle, is more susceptible to the action of MI-65-S than the dynamic phase. The cutaneous touch receptor was not affected (Fig. 8K-M). The muscle spindle previously treated with MI-65-S could no longer respond to succinylcholine (Matsushita, 1964) and decamethonium (Matsushita et al., 19651, which are known to produce a remarkable increase in the frequency of the muscle spindle discharges (Granit et al., 1953). From these results it may be concluded that reduction of muscle spindle discharges by MI-65-S is produced by direct action on the muscle spindle. Owing to the blocking action on the autonomic ganglion, intravenous administration of MI-65-S lowers the blood pressure significantly. However, a possible influence of the fall of blood pressure on the muscle spindleldischargescan be eliminated by the experiment on the spinal cat, where the decrease in frequency of muscle spindle discharges also occurred although no changes in the blood pressure could be detected (Matsushita, 1964). To make sure that the depression of muscle spindle discharges is closely connected with the ataxic behaviour, the following two experiments were undertaken. Firstly, a t the time when MI-6.54 caused severe ataxia in the animal, two types of decerebration, intercollicular and anemic decerebration, were performed. No extensor rigidity, which is known to be caused by abnormal accentuation of the y-activity was observed in the cat decerebrated intercollicularly (Fig. 9A). In this animal, additional removal of the anterior lobe of the cerebellum resulted in marked development of extensor rigidity (Fig. 9B). In the cat decerebrated by ligation of the carotid and basilar

B E H A V I O U R A L A N D ELECTROPHYSIOLOGICAL STUDY OF DRUGS

-

A

145

*'''*-

ImV

I 1 sec

Fig. 9. Effect of MI-65-S on decerebrate rigidity. The muscle stiffness is measured by electromyography of the In. triceps brachii of the cat. (A) Intercollicular decerebration was performed on the ataxic cat. (B) The anterior cerebellar lobe of the cat used in experiment A was removed. (C) The ataxic cat was decerebrated by the method of Pollock and Davis. At the time indicated by the horizontal line below the EMG records, dorsiflexion of the head was performed. (From Matsushita et a/., 1965.)

arteries, highly developed extensor rigidity was observed (Fig. 9C). Thus, MI-65-S reduced y-rigidity but not a-rigidity. The second method consisted of mathematical analysis of sequential discharges of single neuromuscular units recorded from the plantar muscle of the dog in standing posture. As shown in Fig. 10A and B, irregular fluctuation of discharge intervals was more marked in the ataxic state than in the normal state in spite of the mean interval being almost the same. In Fig. IOC, the relation between the mean and the standard deviation of discharge intervals of a number of neuromuscular units is shown. Open circles obtained from the normal state distributed along a curve, while the distribution of most points in the ataxic state, shown by filled circles, shifted to the left and upwards.

Discussion The most striking behavioural syndrome produced by MI-65-S is the long-lasting ataxic state. On the other hand, this compound showed a remarkable depressive action not on the neuromuscular junction and the interneuronal activity of the spinal cord, but on the muscle spindle. Needless to say, the y-system, in which the muscle spindle occupies a very important part, plays a significant role in the maintenance of skeletal muscle tone. Therefore, it seems quite reasonable to consider that the cause of ataxia may depend upon depression of the muscle spindle. It was proved by two Rcqerences p . 147-149

146

R . K I D O , K . Y A M A M O T O A N D A. M A T S U S H I T A

,-. U 2

-E

g U 0

A 50

-

‘ 40

-

0

0

C 30

.

;2 0

t

ul

10

I

50

I

100

I

150 rnsec

71

Fig. 10. Effect of MI-65-S on the discharge pattern of the neuromuscular unit (NMU). (A and B) The interval diagram showing the change in discharge intervals of different NMU’s before (A) and after (B) MI-65-S injection. (C) Standard deviation (s) of intervals was plotted against mean discharge interval (7) on graph. Open circles obtained in control preparation distribute along a curve, but filled circles obtained in ataxic state shift leftwards. (From Matsushita et al., 1965.)

different experiments that the severe ataxia by MI-65-S was certainly accompanied with depression of the muscle spindle. In the first place, the effect of the compound on two types of rigidity was tested. Eldred et al. (1953) showed that decerebrate rigidity by intercollicular section was caused mainly by the high accentuation of y-activity and decreased by section of the dorsal roots. Another type of rigidity, produced by removal of the anterior lobe of the cerebellum or by the anemic method, was independent of the y-system and remained even when the influx of afferent impulses into the spinal cord was decreased or abolished (Granit et al., 1955). According to the present experiment, y-rigidity was depressed by MI-65-S injection, while a-rigidity was not affected by this compound. These results are well explained by the direct blocking action of MI-65-S on the muscle spindle activity.

BEHAVIOURAL A N D ELECTROPHYSlOLOGICAL S T U D Y O F D R U G S

147

The second proof is the leftward shift of 7-s distribution. To estimate the y-activity during ataxia, we analysed mathematically the discharge patterns of a single neuromuscular unit according to Tokizane’s method (Tokizane, 1955). Utilizing the fact that procaine blocks the y-efferents more selectively than the a-motor fibres, Kubota and Oshima (1959) showed that the fluctuation of discharge intervals increased and the 7-s curve shifted leftwards after infiltrating procaine into the muscle nerve of man. In animal experiments, it was reported that in dogs sectioning of the dorsal roots led to marked increase of irregular fluctuation of neuromuscular unit discharge intervals and to severe ataxia (Nomura, 1958). In the present investigation, we observed the same tendency in the discharge pattern of a single neuromuscular unit of the dog as obtained in the de-efferented preparation. Therefore, the leftward shift of 7-s points by MI-65-S may be explained as the result of muscle spindle depression. Many anatomical and physiological investigations into the muscle spindle have been performed by several groups in recent years (cf. Barker, 1962), but there are relatively few pharmacological studies. Especially, reports on a depressive agent that acts directly on the muscle spindle are very scarce and the only one known by the authors is a report on a triazine derivative by Bein and Fehr (1962). As this compound exerts depressive action on y-efferent activity and perhaps spinal synaptic pathways, it may be supposed that its mode of action on the muscle spindle is different from that of MI-65-S. Summary

In the present report, the pharmacological action of a new asymmetrical bisquaternary ammonium salt on the motor system is described. The motive to investigate exactly the motor system is derived from the pharmacological property of this drug to produce a long-lasting ataxia in animals, in spite of its having no considerableeffect on the neuromuscular junction or spinal synaptic mechanisms. MI-65-S depresses the muscle spindle activity, and the stimulating action of succinylcholine or decamethonium on the muscle spindle is antagonized by this compound. In ataxia elicited by MI-65-S, the cat failed to show y-rigidity, while the a-type of rigidity by anemic decerebration or removal of the anterior lobe of the cerebellum was easily developed. I n the ataxic state a leftward shift of 7-s distribution obtained from the dog’s plantar muscle was observed. From these results it may be concluded that MI-65-S brings about a long-lasting ataxia in the mammal by acting directly on the muscle spindle, producing a decrease in frequency of its discharges, which may be followed by a serious depression in the function of the y-system. REFERENCES

BARKER,D., Editor, (1962); Symposium on Muscle Receptors. Hong Kong University Press. BEIN,H. J., AND FEHR, H. U., (1962); Depression of muscle spindle activity. A new type of pharmacological action? Brit. J . Pharmaco6., 19, 375-384. BLAKE, H., GERARD, R. W., AND KLEITMAN, N., (1939); Factors influencing brain potentials during sleep. J . Neurophysiol., 2, 48-60.

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BRADLEY, P. B., AND ELKES,J., (1Y53); A technique for recording the electrical activity of the brain in the conscious animal. Electrornceph. clin. Neurophysiol., 5, 451-456. CLARK, S. L., AND WARD,J. W., (1945); Electroencephalogram of different cortical regions of normal and anaesthetized cats. J. Neurophysiol., 8, 99-1 12. DEMENT,W., (1 958); The occurrence of low voltage, fast electroencephalogram patterns during behavioural sleep in the cat. Electroenceph. clin. Neurophysiol., 10, 291-296. DERBYSHIRE, A. J., REMPEL, B., FORBES, T., AND LAMBERT, E. F., (1936); Effects of anesthetics on action potentials in the cerebral cortex of the cat. Amer. J. Physiol., 116, 557-596. ECCLES,J. C., (1964); The Physiology of Synapses. Berlin, Springer-Verlag. ELDRED, E., GRANIT,R., AND MERTON,P. A., (1Y53); Supraspinal control of the muscle spindle and its significance. J. Physiol., 122, 498-532. FISCHLR, G., SAYER,G. P., AND BICKFORD, R. G., (1957); Histologic changes in the cat’s brain after introduction of metallic and plastic coated wire used in electroencephalography. Proc. Stafl Meetings Mayo Clinic, 32, 14-22. GIBBS,F. A,, AND GIBBS,E. L., (1950); Atlas of Electroencephalography, 1, Cambridge, AddisonWesley Press. GRANIT,R., (1955); Receptor and Sensory Perception. New Haven, Conn., Yale University Press. GRANIT,R., HENATSCH, H. -D., AND STEG,G., (1956); Tonic and phasic ventral horn cells differentiated by post-tetanic potentiation in cat extensors. Acfa physiol. scand., 37, 114-126. GRANIT,R., HOLMGREN, B., AND MERTON,P. A., (1955); The two routes for excitation of muscle and their subserviency to the cerebellum. J. Physiol., 130, 213-224. GRANIT,R., SKOGLUND, S., AND THESLEFF, S., (1953); Activation of muscle spindle by succinylcholine and decamethonium. The effect of curare. Acta physiol. scand., 28, 134-151. HENDLEY, C. D., LYNES,T. E., AND BERGER,F. M., (1957); Effect of meprobamate on electrical activity of thalamus and other subcortical areas. Tranquilizing Drugs. Publ. No. 46, Anier. Ass. Advanc. Sci., Washington, D. C. (p. 35). HESS,R., JR., KOELLA, W. P., AND AKERT,K., (1953); Cortical and subcortical recordings in natural and artificially induced sleep in cats. Electroenceph. d i n . Neurophysiol., 5. 75-90. JOUVET, M., A N D MICHEL, F., (1960); Sur les voies nerveuses responsables de l’activite rapide corticale au cours du sonimeil physiologique chez le chat (phase paradoxale). C . R. SOC.Biol. (Paris), 154, 995-998.

KAADA,B. R., (1951); Somato-motor, autonomic and electrocorticographic responses to electrical stimulation of “rhinencephalic” and other structures in primates, cat and dog. Actaphysiol. scand., 24,SUPPI.83, 1-285. KAADA, B. R., AND BRULAND, H., (1960); Effects of chlorpromazine on the “attention” (orienting), fight and anger responses elicited by cerebral stimulation. Acta physiol. scand., 50, Suppl. 175, p. 81. KAWAMURA, H., NAKAMURA, Y., AND TOKIZANE, T., (1961); Effect of acute brain stem lesions on the electrical activities of the limbic system and neocortex. Jap. J. Physiol., 11, 564-575. KIDO,R., AND YAMAMOTO, K., (1962); An analysis of tranquilizers in chronically electrode implanted cat. Int. J. Neuropharmacol., 1, 49-53. KIKUCHI, T., (1961); Electroencephalographic studies on the action of reserpine in the rabbit and combined action of reserpine and methamphetamine. Folia pharmacol. jap., 57, 173-192 (in Japanese). KOBAYASHI, T., MURAYAMA, S., YOKOTA,S., A N D SASAKI, S., (1958); Pharmacological studies on the electrical activity of the central nervous system with the implanted electrode technique. Folia pharmacol. jap., 54, 12g (in Japanese). KOELLA, W., HESS,R., JR., AND AKERT,K., (1951); Zur Technik der Registrierung hirnelektrischer Erscheinungen im Rahmen des subcorticalen Reizversuches bei der Katze. Helv. physiol. pharmacol. Acta, 9,316-325. KUBOTA, K., AND OSHIMA,T., (1959); Effects of gamma blocking on muscular activity and their relation to myasthenic state. Neurol. med.-chir., 1, 171-179. LIM, R. K. S., CHAN-NAO LIU AND MOFFITT, R. L., (1960); A Stereotaxic Atlas of the Dog’s Brain. Springfield, Thomas. MATSUSHITA, A,, ( I 964); Pharmacological properties of a bis-quaternary ammonium salt of the dibenzobicyclo(2.2.2)octane series, especially its depressant effect on the muscle spindle. Jap. J. Pharmacol., 14, 434-447. MATSUSHITA. A., YANAGISAWA, N., AND SHIMAZU, H., (1965); A study of muscle spindle depression and ataxia caused by a new unsymmetrlcal bis-methonium compound in mammals. J. Pharmacol. exp. Ther., 147, 343-349.

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MONNIER, M., (1957); Topic action of psychotropic drugs on the electrical activity of cortex, rhinencephalon and>nesodiencephalon. Psychorropic Drugs. S. Gardttini and V. Ghetti, Editors. Amsterdam, Elsevier (pp. 217-234). NAKAJIMA, I., (1955); EEG changes induced by intravenous anesthesia. J . physiol. SOC.Jap., 17, 607-618 (in Japanese). NOMURA, S., (1958); Eleclromyographic studies on the function of the skeletal muscles. VI. Characters of the discharge-interval-time series of a single NMU. Part 4. The t-s curve of the dog. Jap. J . vet. Sci., 20, 223-229. PRESTON, J.-B.,-(1956); Effect of chlorpromazine-on the central nervous system of the cat; a possible neural basis for action. J . Pharmacol. exp. Ther., 118, 100-115. RANDALL, L. D., (1961); Pharmacology of chlordiazepoxide (Librium). Dis. nerv. Syst., 22, 7-15. RHEINBERGER, M. B.,-ANDJASPER, H. H., (1937); Electrical activity of the cerebral cortex in the unanesthetized cat. Amer. J. Physiol., 119, 186-196. SHIMAZONO, Y., HORIE,T., YANAGISAWA, Y., HORI,N., CHIKAZAWA, S., AND SHOZUKA, H., (1960); The correlation of the rhythmic waves of the hippocampus with the behaviors of dogs. Neuroi. med. chir., 2, 82-88. TAVERNER, D., (1952); The action of u, P-dihydroxy-y-(2-methylphenoxy)-propane (Myanesin) on the spinal cord of the cat. Brit. J . Pharmacol., 7, 655-664. TOKIZANE, T., (1955); Functional differentiation of human skeletal muscles. Kagaku, 25, 229-233, 29 1-297 (in Japanese). TOKIZANE, T., (1958a); Physiology of corpus amygdaloideum. Recent Adv. Res. n e w . Syst., 2,493-541 (in Japanese). TOKIZANE, T., (1958b); Electrical activity of the limbic system. Proc. VlIth Ann. Meet. Jap. EEG SOC., Tokyo, 138-140. TOKIZANE, T., KAWAMURA, H., AND IMAMURA, G., (1960); Hypothalamic activation upon electrical activities of paleo- and archicortex. Neuroi. med.-chir., 2, 63-76. TOKIZANE, T., KAWAMURA, H., IMAMURA, G., KUMAGAI, H., A N D FUKUHARA, T., (1958); Effects of various anesthetics on the electrical activities of neo-, paleo- and archicortex of the cat. Folia pharmacoi. jap., 51, 125 (in Japanese). YAMAMOTO, K., ( I 959); Studies on the normal EEG of the cat. Comparison bctween the EEG of fixed cats and unfixed cats seen from the skull and subcortical leads in various consciousness levels and the corresponding behaviour. A . R. Shionogi Res. Lab., 9, 1125-1164 (in Japanese). YAMAMOTO, K., (1962); Neurophysiological studies on the nature of sleep. Suppl. Xlth Ann. Meet. JUP.EEC SOC.,pp. 12-16. YAMAMOTO, K., AND KIDO,R . , (1961); Hippocampal arousal wave as an indicator of electrical activities of the brain. Brain Nerve, 13, 887-894 (in Japanese). YAMAMOTO, K., AND KIDO,R., (1 Y62a); Neurophysiological studies on the nature of sleep. Neural mechanisms related to ‘activated sleep’. Clin. Psychiat., 4, 821-830 (in Japanese). YAMAMOTO, K., AND KIDO,R., (196213); Comparative studies on theeffectsof tranquilizers, barbiturates and morphine with implanted electrodes in cats and dogs. Brain Nerve, 14,591-608 (in Japanese). YAMAMOTO, K., AND KIDO,R., (1964); An analysis of central acting drugs using animal experiments. Association and dissociation between EEG and behaviour. Brain Nerve, 16, 44-56 (in Japanese). YAMAMOTO, K., YOSHIOKA, M., NAKAMURA, Y., AND KAWAMURA, H., (1961); Electrophysiological study of effects of morphine on the central nervous system. Brain Nerve, 13, 327-350 (in Japanese). YOKOTA, S., (1958); Physiological and pharmacological studies on the electrical activity of the brain in the conscious cat by the implanted electrode method. Folia pharmacol. jap., 54, 963-973 (in Japanese). YOKOTA, S., (1959); The effect of chlorpromazine on the electrical activity of the brain in the conscious cat by the implanted electrode method. Folia pharmacol. jap., 55, 966-980 (in Japanese).

150

Studies on the Human Triangular Tract of Helweg MICHIO OKAMOTO Departtnenf of Anatomy, racrrlty of‘ Medicine, Kyoto University, Kyoto (Japan)

The triangular tract was first described minutely by Helweg in 1888 as a fiber bundle which specifically existed in the spinal cord of psychopathic patients having emotional defects. In accord with the shape of its cross section at the level of the upper cervical spinal cord, the tracthas been called the ‘Dreikantige Bahn’ of Helweg. Since then, it has been intensively studied by many neurologists and neuroanatomists. Nevertheless, it still remains one of the most ambiguous tracts in the central nervous system. The following two reasons may account for the uncertainty in understanding the tract. One is the extreme fineness of the fibers which constitute the major portion of the tract. In injury of these fibers by a tumor or hemorrhage, theextraordinary thinness of the fibers has made it difficult to prove the degeneration of this tract with certainty. The second reason is that no animal has ever been definitely known to have any tract homologous to the triangular tract of the human spinal cord. Even for primates, opinions are divided as to whether some of them have the homologous tract or not. Therefore, no definite conclusion has been obtained, which could usually be expected from animal experiments. The major problems which have been the objects of intense discussion about this tract are as follows.

( I ) Direction of the tract (descending or ascending) Whether Helweg’s tract is centrifugal or centripetal has been a point of dispute. It has been impossible to use animals to determine the direction of this tract experimentally. Therefore, the main source which could provide some knowledge about the direction of this tract has been the human spinal cord having lesions of any nature, and these have been studied as to the second degeneration using the Marchi or the Weigert method. The results, however, have not produced agreement as to its direction, as Obersteiner (1901) admitted. Some investigators observed ascending degeneration of the tract after lesions ofthe spinal cord, and others found descending degeneration after lesions at a higher level of the brain stem. The major investigators in the past and their opinions about the direction of the triangular tract of the human spinal cord are listed in Table I. The Table shows that von Bechterew(l885,1901) changed his opinion in the course of his study. Kattwinkel andNeumaier ( I 907) thought that fine fibers of the tract might be descending, and the larger fibers might be ascending, according to their findings in a case with a lesion i n

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TABLE I INVESTIGATORS O N T H E H U M A N TRIANGULAR T R A C T OF HELWEG A N D THEIR O P I N I O N A B O U T ITS DIRECTION

Date Descending: 1882 I888 1897 1901 1901 1902 1910 1913 1914

Author

1916 1935 1937

Meyer Helweg Reinhold Von Bechterew Obersteiner Ransohoff Thalbitzer Ziehen Antone and Zingerle Schwartz Pollak Weisscheidel

Ascending : 1894 1903

Von Bechterew Von Dydinski

1910

Goldstein

1911 1916

Edinger Kaplan

Lesion

Staining method

Hemorrhage in pons Psychopathic patient Hemorrhage in pons Normal spinal cord Tumor in olive Cysts in pons Normal spinal cord Normal spinal cord Atrophy of olive

Weigert Carmine Weigert Weigert Marchi Weigert Weigert Weigert Weigert

Normal spinal cord Normal spinal cord Normal spinal cord

Weigert Weigert Weigert

Normal spinal cord Myelitis in the thoracic segment Tumor at lumbar intuniescence Normal spinal cord Normal spinal cord

Weigert Marchi Marchi Weigert Weigert

the cerebral pedunculus. Some investigators in Table I used the Weigert staining technique to show the degeneration. But the stainability of the extremely fine fibers which constitute the major constituent of the tract is weak and the tract appears pale even in the normal spinal cord when stained as usual. It is therefore necessary to use the Marchi method in order to prove definitely the degeneration (Ziehen, 1913). The Marchi method, however, is always capricious and, in addition, these extremely fine fibers lose their osmium granules in the short time of 9-10 days after lesions. Therefore it is indispensable to use adequate material in terms of the time span after the lesion (Obersteiner, 1901). ( 2 ) Upper limit of the tract (relation with the olivary nucieus) When Helweg described the details of this tract, the emphasis was placed on the disappearance of this tract at the level of the caudal third of the olivary complex in connection with the upper termination of this tract. However, he drew no definite conclusion as to whether the tract originated or terminated in the olivary nucleus. Nor did Von Bechterew (1894), who first called the tract the ‘Olivenbundel’ because the tract disappeared abruptly after the appearance of the olivary nucleus. Later, he adopted the name of ‘fasciculus periolivaris’ in order to avoid the misunderstanding References p . 1811182

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about the origin of the tract and to imply that the tract passed by the olivary nucleus. Many other investigators have claimed the origin of the triangular tract to be in the olivary nucleus (Pick, 1898; Thalbitzer, 1910; Antone and Zingerle, 1914), as will be discussed later. It is, however, surprising that no one has ever proved a definite connection between the olivary nucleus and the tract. Besides the above investigators, those who found descending degenerations of the triangular tract after lesions in the brain at the higher level than the olivary,nucleus, presumed the origin of the tract to be in the pons, the thalamus, the striatum or the cerebral cortex (Marinesco and Moeli, 1892; Russell, 1898; Reinhold, 1897; Spiller, 1898; Ransohoff, 1902; Kattwinkel and Neumaier, 1907). ( 3 ) Lower limit o f t h e tract The lower limit of the tract has usually been reported to reach the C5 spinal segment, and in rare cases as far down as C8, although some previous observers reported a lower termination of the tract such as thoracic and lumbal segments. For instance, Goldstein (1910) recognized the degeneration of the tract down to lumbar segments after the lesion of the spinal cord by a tumor a t the cervical segment. Mott and Tredgold (1900) reported the degenerated tract of Helweg down to the lumbar intumescence after thrombosis of the middle cerebral artery. Kattwinkel and Neumaier ( I 907) reported that it could be traced down to the Th2. Concerning the fate of the fibers of the tract at the lower termination, Helweg presumed the possibility of their entering the anterior horn or the anterior root. Thalbitzer (1910) observed that the fibers joined the anterior roots. Schwartz (1916) could not find any evidence to favor this conclusion and assumed the possibility of their entering the anterior gray matter on the ground of the medial and dorsal deviation of the fibers composing Helweg’s tract at the level of their termination. Thus, opinions are divided as to the level of the termination and the further fate of the fiber bundle of Helweg’s tract.

(4) Fibers composing the tract The major constituents of the tract of Helweg are extremely fine fibers measuring around 1 p in diameter. Among these fine fibers there are larger fibers measuring from 3 p to 17 p scattered over the area of the tract. The origins of these two kinds of fibers are considered to be quite different according to the results obtained from myelogenetic studies. As for the origin of the larger fibers, it is possible that the fibers composing the adjacent tracts have come astray into the area of the triangular tract. Adjacent tracts which have been considered include the spinotectal tract, the spinothalamic tract (Von Bechterew, I901), the anterior spinocerebellar tract (Obersteiner, 1901) and the ventrolateral pyramidal tract of Barnes (Yamakawa, 1914). ( 5 ) Functional signi$cance of the tract Helweg, and later Reinhold (1 897), thought that this fiber tract was specifically

present in the spinal cord of psychopathic patients affected in their emotional aspect and might be concerned with vasomotor function. Ziehen (1913) was inclined to

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believe that this tract might be concerned with bodily equilibrium. Schwartz (1916) attributed the delicate innervation of neck muscles and elevation of the head to the functions of this tract from the findings that this tract was limited only in the upper level of the cervical spinal cord, absent in animals, and poorly developed in the newborn child. Kaplan’s opinion (1916) was that the tract gave the fine control to the movement 9f the upper extremities, especially fingers, by means of connections with the cerebellum through the spino-olivo-cerebellar tract.

(6) Comparative anatomy Helweg did not find the homologous tract in the calf and the sheep. According to Ziehen (1913) existence of this tract in rodents was doubtful. KapIan(1916)disproved its existence in rodents, but he recognized a structure similar to the ‘diffuse formation’ in the anterior and lateral funicles of the rodent spinal cords. According to his study, the chimpanzee, the gorilla, and the orang-utan have a tract homologous to that of the human Helweg’s tract. Schwartz (1916) did not recognize the tract of Helweg in the spinal cord of the gorilla and the orang-utan. Ogawa(1943) reported that an analogous tract was found in the cat, the rabbit and the muntjak. Thus, there are many ambiguities about this tract. Because the presence of the tract has been confirmed with certainty only in the human spinal cord, and animal experiments cannot be carried out, elaborate and accurate observations of the normal human spinal cord are still important. In this paper, Part I will give a detailed description of the normal triangular tract, Part I1 will deal with the myelogenetic details about this tract obtained from human embryos stained with the Weigert technique, and Part I11 will give conclusive information about this tract on a brain whose olivary nucleus was almost completely atrophied. P A R T I. D E T A I L S O N T H E H U M A N T R I A N G U L A R T R A C T

Details of the triangular tract of Helweg were studied in serial sections of the spinal cord and the medulla oblongata of 18 patients, stained by the Weigert technique. Materials and methods

Materials were obtained from bodies ranging from 14 to 78 years of age, who have not been proved to have had any mental or nervous diseases in their past life histories: Case No.

Age

1 2 3 4 5 6

14 20 23 27 29 36

7

40 44

8 9

50

References p. 181/182

Cause of death

Heart failure Encephalitis Poisoned by sleeping drug Unknown Heart failure Death penalty Stomach cancer Heart failure Acute pancreatitis

Case No.

Age

10 11 12 13

52 55 78 Unknown

14

15 16 17 18

Cause of death

Lung tuberculosis Caxer Intestine occlusion Unknown 9,

,,

,, ,,

1,

,, 7,

154

M. O K A M O T O

The spinal cords were taken out together with the medulla oblongata, because the transition region from the spinal cord to the medulla oblongata is the most important portion of this tract. Serial transverse sections of 30 y thickness were stained by the Weigert-Pal method. Sagittal serial sections of 40 y thickness were obtained from one case at the level from the upper border of the pons to the C4 segment. Results The general features of the triangular tract of Helweg will be given first, and the special findings will be referred to in the appropriate places. Detailed description of the tract will be properly begun at the level of the CI segment, where the tract usually has its typical triangular shape in cross-section, thereby deserving the name of the triangular tract. Jt is located at the transition region between the anterior funicle and the lateral funicle at the superficial part of the spinal cord, thus making a flat triangle with its centrally directed tip and the base along the anterolateral surface of the spinal cord. The dorsal borders are not always clear as they are intermingled with the fibers from those tracts that surround the tract of Helweg. The fibers composing the tract can be classified into 5 types according to their caliber. The major constituents of the tract are extremely fine fibers measuring less than 1 y in diameter. Some of them are well stained by the Weigert technique, but the majority remain unstained at the usual grade of differentiation ofthe staining technique. They look yellowish, making the granular ground substance or background on which other types of fibers are diffusely scattered. It is due to these unstained extremely fine fibers that the tract of Helwegis easy to belocalized in the spinal cord. The third component comprises fine fibers measuring around 1 y in diameter, well stained by the Weigert technique and provided with a distinct central lumina. The fourth constituent comprises medium sized fibers, and the fifth large fibers measuring from 10 p to 17 y in diameter. The analysis of the fiber caliber of the tract at the various levels is shown in Table IT and Fig. 1. As Table I1 shows, 80 to 90% of the fibers of the tract are composed of the fine fibers measuring less than 3 y i n diameter, approximately 60 % of which are the extremely fine fibers measuring less than 1 p in diameter. Below the level of the C2 spinal segment, the extremely fine fibers tend to concentrate towards the surface of the spinal cord. The larger fibers are more predominant in the deeper layer than in the superficial layer. Here, it would be appropriate to refer to the structure called the ‘diffuse formation’, which has been discussed in relation to the tract of Helweg. Since Helweg first described the tract, it has been observed that extremely fine fibers like those in the tract are intermingled in groups among fibers composing part of the anterior and lateral funicles. They are found in the lateral portion of the anterior funicle and the anterior two-thirds of the lateral funicle at the level of C1. At the higher level, where the tract of Helweg is located at the lateral aspect of the pyramis medullae oblongatae, the ‘diffuse formation’ seems to join the triangular tract. This might be the reason why the tract of Helweg appears to reach its maximum volume at this level.

155

H U M A N TRIANGULAR TRACT OF HELWEG

T A B L E I1 A N A L Y S I S O F T H E F I B E R C A L I B E R O F THE T R I A N G U L A R T R A C T O F H E L W E G

AT V A R I O U S L E V E L S

Parts

No. offibers measured

Total No. of jibers

Medulla oblongata c1 c3 c5

5276

ca. 47,500

4427 1733 222

ca. 39,800 ca. 16,000 222

Less than

Upto17p

Upto3p ( %)

uplolop ( %)

52.0

34.6

13.0

0.3

53.2 52.8 46.8

35.5 35.2 21.8

10.6 11.0 21.4

0.4 0.8 2.3

1P ( %)

( %)

%

-Medulla Oblongata

60-

c1 _.___ - --. .-.c 3

;1

_ _ _ - - - -c5 -

--.. ----_...._---___ i i

3

4

5

6

7

€3

9 lO1lp

Fig. 1. Analysis of the fiber caliber of the triangular tract of Helweg at levels ofthemedulla oblongata C I , C3, and C5.

In the lower segments, the extremely fine fibers of the ‘diffuse formation’ seem to decrease in number leaving mainly fine fibers. At the level of the C8 segment, which was the lowest level of the serial sections available, they still existed in abundance. In the caudal direction the tract of Helweg gradually decreases in size from the mediodorsal side and becomes flatter like a narrow band attached to the anterolateral surface of the spinal cord, being penetrated by anterior rootlets. It is always difficult definitely to delineate the caudal termination of the tract of Helweg when the ‘diffuse formation’ is taken into consideration. As far as the extremely fine fibers forming the triangle at the level of the C1 segment are concerned, the tract of Helweg usually terminates at levels between spinal segments C4 and C7. In the 36 sides of the 18 cases, it ended at C4 in 5, at C5 in 13, at C6 in 11, and at C7 in 7 Referencts p . l S l / l S 2

156

M. O K A M O T O

sides. So it would be reasonable to conclude that it terminates at the levels between thc spinal segments of C4 and C7, and usually at the levels of C5 and C6. No conspicuous difference in the levels of their termination on both sides could be recognized. As for the behaviour of the fibers in their termination, they were neither observed to deviate dorsally or medially and then to terminate in the anterior horn, nor could they be traced into the anterior roots. When the tract was followed cranially, it seemed to increase in volume and made a little larger triangle with an obtuse angle directed ventrally at the level of the pyramidal crossing. It was located-directly lateral to the growing pyramis medullae oblongatae. At these levels larger fibers tended to invade from the deeper layer, and the fine fibers along the superficial margin of the spinal cord moved dorsally as a whole. At the level of the appearance of the medial accessory olivary nucleus, the tract filled the space surrounded ventrally by the pyramis; medially by the lateral tip of the accessory olivary nucleus and the lateral border of the reticular formation; dorsally by the ascending fiber tracts situated at the lateral periphery of the medulla. It occupied the largest area at this level. Here at this level it was almost impossible to distinguish fibers of the triangular tract from those of the ‘diffuse formation’. Though both were continuous with each other, fibers were not so extremely fine in the dorsomedial portion, which was considered to belong to the ‘diffuse formation’. An abundance of fine fibers was seen along the lateral aspect of the reticular formation at this level. Some of these fine fibers were found to deviate from mediocaudal to laterocranial and then to run vertically. At a little higher level, the fibers of the triangular tract were divided into many layers by the anterior external arcuate fibers running along the lateral surface of the medulla. In accord with the appearance of the lower pole of the main olivary nucleus, they seemed to be pressed laterally towards the periphery of the medulla oblongata. At the same time, they seemed abruptly to change their direction from vertical to obliquely dorsolateral, as if they were trying to avoid the main olivary nucleus. At the level of the caudal third of the main olivary nucleus they were observed as obliquely running ’fibers divided into several layers by the anterior external arcuate fibers. At the middle level of the main olivary nucleus, where it reaches full development, the fibers among these layers seemed to regain the longitudinal direction. These fibers, however, were found to be .larger than the extremely fine fibers of Helweg’s tract at the lower level. They might already be the fibers of the central tegmental tract approaching the olivary nucleus. It was impossible to decide the exact termination of these fibers under these conditions. During their course along the lateral periphery of the olivary nucleus, no fibers seemed to deviate and enter the olivary nuclear complex. Also on the longitudinal serial section, they deviated laterally with the growth of the main olivary nucleus, and no fibers were seen to join the olivary nucleus. Tn other words, the fibers of the tract and the olivary nuclear complex were always apart from each other, and no direct fiber connection was observed with certainty. No marked differences were observed between the features of the tracts on both sides. Even in case No. 5, where Helweg’s tract was deformed by the ventrolateral pyramidal

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157

tract of Barnes, the change occurred in the same way on both sides. In case No. 3, the medial movement of the tract was less on the right side than on the left, and it was found that this was due to the pyramidal fibers above that level. The most frequent aberrant tract in the proximity of the tract of Helweg is the ventrolsteral pyramidal tract of Barnes. In case No. 5 the ventrolateral pyramidal tract of Barnes was located in the ventrolateral part of the left triangular tract along the surface of the spinal cord, and the triangular tract took a comma figure. In cases Nos. 16, 17 and 18, the ventrolateral pyramidal tract of Barnes was located in the place where the triangulat tract was usually expected. Discussion ( I ) Existence and the extent of the tract l n all cases examined here, the tract of Helweg was always recognized. The density and the size of the area were subject to variation. There were some cases in which the tract was deeply stained and did not appear so conspicuous as the usual triangular area with the pale color. Even in these cases, recognition of the extremely fine fibers under the higher magnification revealed the presence of the tracts in the usual place. There was no case of psychosis in the patients from whom the materials were obtained. Though Helweg thought that this tract was characteristic of psychopathic patients, it is disproved here. There are generally no conspicuous differences in the features of the triangular tracts between both sides, unless any anomaly is present in other fiber tracts surrounding the tract of Helweg on either side at the higher level. The tract which most frequently affects the triangular tract is the ventrolateral pyramidal tract of Barnes (1 901). As this fact is important in connection with the problem of the lower termination of the triangular tract, it will be discussed later. The lower limit is usually between the levels of C4 and C7. The most frequent levels are C5 and C6, as has been generally recognized by Helweg (I 888), Thalbitzer (1910) and others. As for the reports in which the tract of Helweg was traced down to the level of the lower thoracic and lumbar segments, it was always doubtful whether it was really the tract of Helweg. There was always a possibility that other fibers which were intermingled in the triangular tract were mistaken for a part of thetract. Themost frequent and probable fiber bundle being located in the area of the triangular tract and mistaken for a part of the triangular tract is the ventrolateral pyramidal tract of Barnes (Russell, 1898; Spiller, 1902; Mott and Tredgold, 1900; Kattwinkel and Neumaier, 1907; Yamakawa, 1914). In this report, 3 cases of the tract of Barnes were found to be located in the midst of the area of the triangular tract. Masuda (1963) reported 4 cases ofthe pyramidal tract of Barnes out of 35 cases which’were examined with special reference to the triangular tract of Helweg (0.8 %). Such a close topographical relation between the triangular and pyramidal tracts, together with the concomitant degeneration of both which was sometimes observed in the pathological materials, made one think of the possible connection of both References p .

1811182

158

M. O K A M O ' I ' O

tracts in terms of the origin. The myelogenetic study, however, does not favor this assumption as will be discussed later. The triangular tract decreases in the area gradually at the lower levels where it is composed predominantly of the extremely fine fibers and appears pale. It is, however, not clear whether this is due to a decrease in number of the extremely fine fibers in the triangular tract or to the invasion of the larger fibers from the fiber tracts dorsal to the triangular tract. As to the fate of the fibers of the triangular tract, special attention was paid to the behavior of the extremely fine fibers at the level of their termination. And no extremely fine fibers have been observed to deviate dorsally or medially and enter the anterior horn (Helweg, 1888; Schwartz, 1916) or join the anterior roots (Thalbitzer, 1910). Even in the longitudinal serial sections, it was impossible to trace such a course of the extremely fine fibers of the triangular tract, as the latter is located so far ventrally from the gray matter. Many fine fibers, however, were observed to run transversely at the border region between the anterior horn and the ventrolateral funicle. These fibers were also recognized by Helweg and offered as possible evidence that the fibers of the 'diffuse formation' might originate in the spinal gray matter. Considering the close similarity in fiber composition between the triangular tract and the 'diffuse formation', the possible connection between the anterior horn and the triangular tract cannot be rejected, even though the connection has not yet actually been proved. (2) Property of'the fibers composiPtg the tract There are two categories of fibers according to their origin : first, the extremely fine fibers, stained and unstained, measuring around or less than I ,u in diameter; second, the fine, medium sized and large fibers ranging from 3 ,u to 17 ,u in diameter. The first category is the major component and gives the characteristic appearance to the tract. The stainability of these extremely fine fibers depends upon the grade of differentiation in the process of the Weigert staining technique. Some of them are stained, and the rest remains unstained at the usual differentiation of the staining procedure, making the yellow granular background for the other fiber components. These extremely fine fibers belong to the finest fibers in the central nervous system. They are sometimes finer than fibers of the dorsal longitudinal fascicle, and similar i n appearance to the fibers constituting Lissauer's terminal zone a s far as the fiber caliber is concerned. According to the estimate by Helweg (1 888) the number of fibers composing the triangular tract amounted to 160,000. As Table TI shows, the number of fibers of the triangular tract is now roughly estimated at 40,000 at the level of C1. This discrepancy in number is considered to depend upon a difference in staining technique (Helweg: carmine). The larger fibers intermingled in the area of the tract of Helweg have usually been considered to havecome astray from other fiber tracts. The different behavior between the extremely fine fibers and the larger fibers at the different levels of the spinal cord

HUMAN TRIANGULAR TRACT OF HELWEG

159

and the medulla oblongata favor this assumption. Thus the larger fibers are more numerous at the lower levels of the spinal cord than at the higher levels. At the lower level of the medulla oblongata, where the pyramis and the caudal pole of the medial accessory olivary nucleus are found, the area of the extremely fine fibers can be completely devoid of the larger fibers. The fiber tracts which have been considered in this connection were the anterior spinocerebellar tract, the spinotectal tract, the spinoreticular tract and the anterolateral pyramidal tract of Barnes. The ventrolateral pyramidal tract of Barnes may be omitted from the possible origin of the larger fibers intermingled in the tract of Helweg, because the former tract is always located as a discrete fiber bundle, and not diffusely distributed in the area of the latter tract. From the topographical point of view, the spinothalamic tract, the reticulospinal tract, the tectospinal tiact and the vestibulospinal tract should also be considered as possible origins of these larger fibers.

( 3 ) Relation between the tract and the olivary nucleus As cited above, the olivary nucleus has been the object of intense discussion in terms of the origin or the terminal of the tract of Helweg. However, so far no convincing evidence has been obtained which definitely proves this assumption. For instance, Thalbitzer (1910), the most recent and detailed observer of the triangular tract, paid special attention to the findings of the ‘Vlies’ of the olivary nucleus. He insisted that he could recognize the fibers belonging to the triangular tract, to the ‘diffuse formation’ and to the central tegmental tract separately in the ‘Vlies’. Using not only horizontal serial sections but also vertical ones, he suggested that the triangular tract would be connected with the lowest portion of the olivary nucleus, the ‘diffuse formation’ with the middle level of the anterior lamella of the olivary nucleus, and the central tegmental tract with the upper portion of the olivary nucleus. Considering this in connection with his finding that the fibers of the triangular tract and the ‘diffuse formation’ left the spinal cord through the anterior roots, he further concluded that the triangular tract and the ‘diffuse formation’ originated in the olivary nucleus and went down to the anterior roots of the spinal cord. However, the fibers of the triangular tract and the ‘diffuse formation’ are subject to severe disturbance of direction immediately below the lower pole of the principal olivary nucleus, as was stated minutely in the results. It is almost impossible to follow the fibers continuously to the olivary nucleus, as Thalbitzer himself admitted that “Der Weg der einzelnen Fasern durch das Vlies der Olive aber kann man in der Regel nicht verfolgen”. This would be all that one can expect from the normal preparation stained by the Weigert method. Of course there is a possibility that the fibers of the triangular tract and the ‘diffuse formation’ might have a connection with other nuclei that exist in the proximity of the olivary nucleus such as the nucleus conterminalis, nucleus conterminalis accessorius and the reticular formation of the lower medulla. In fact the fine fibers are abundant along the lateral aspect of the reticular formation of the lower medulla, and some of them are observed to deviate from the transverse to the vertical direction. These Rrfriences p . 1811182

I60

M . OKAMOTO

fibers indicate a possibility of their either coming from or going to the reticular formation. Either possibility is important in terms of the origin or the termination of the fine fibers composing the ‘diffuse formation’. Nevertheless it would be natural to think that the majority of the fibers of both the triangular tract and the ‘diffuse formation’ have a connection with the olivary ducleus, considering the amount of the fibers of both, the volume of the olivary nucleus and their topographical interrelation. Summary

Details of the triahgular tract of Helweg were studied in serial sections of 18 cases of the human spinal cord and medulla oblongata stained by the Weigert method. From the general features of the tract the following findings were obtained: ( I ) The triangular tract of Helweg always exists in the medulla oblongata and the upper cervical spinal cord usually down to C5 or C6. Rostrally followed, it terminates at the level approximately of the caudal third of the olivary complex. (2) The major and characteristic component of the tract is the extremely fine fibers less than and around 1 p in diameter. They belong to the finest fibers in the central nervous system. (3) Though no definite evidence could be obtained for the origin or termination of the tract in the olivary nucleus, it seems most likely that the triangular tract is closely related with the olivary nucleus, judging from the behavior of the fibers of the tract in the proximity of the nucleus. (4) No clear evidence was obtained to prove that the triangular tract actually entered the anterior horn or joined the anterior roots. (5) Some of the fibers of the ‘diffuse formation’ were observed to have come from or gone to the spinal gray matter and the reticular formation of the lower medulla. (6) The ventrolateral pyramidal tract of Barnes was the most frequent tract which was located in the area of the tract of Helweg. P A R T 11. M Y E L O G E N E T I C S T U D Y O F T H E T R I A N G U L A R T R A C T O F H E L W E G

As stated above, it has been almost impossible to draw any definite conclusion about the entity of the triangular tract of Helweg from normal preparations stained by the Weigert technique. The myelogenetic study was undertaken to obtain information which might further clarify its entity. As for the myelogenetic behavior of Helweg’s tract, a few reports are available. According to Von Bechterew ( I 899) the fine fibers which make the major constituents of the tract become myelinated in about one month after birth, later than the pyramidal tract. The larger fibers intermingled in the tract are myelinated earlier than the fine fibers. Obersteiner (1901) was in accord with Von Bechterew i n the view that myelination of the tract of Helweg was later than that of the pyramidal tract. Schwartz (1916) did not recognize any myelination of the tract in’the * fetus of 10 months. It was rare i n the newborn and usually began at 1-5 years after birth,

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to reach the completion only after 10 years. In the report of Schwartz it is not always clear whether he is concerned with characteristic fine fibers of the tract of Helweg or the tract as a whole including both fine fibers and larger fibers.

Materials and methods The materials used in this study were as follows: fetuses of 6, 8 , 9 and 10 months old, a newborn, a 2-year-old girl, a 14-year-old boy and a 54-year-old man. The materials were cut into blocks 3-5 mm long and kept in Miiller’s fluid for 3 weeks. They were then embedded in celloidin, and the materials from the 2-year-old girl, the 14-year-old boy and the 54-year-old man were cut into serial sections of 25 p. Materials from fetuses and the newborn were cut into serial sections of 30 p. They were stained by the Weigert-Pal technique. The nervous tracts were customarily identified and studied myelogenetically. Results The grades of myelination in the fetal and postnatal periods are listed in Table 111. The detailed description of the myelogenetic findings will be limited to the tract of Helweg, and the other fiber tracts will only be referred to when necessary in connection with the tract of Helweg. In the 6-month-old fetus, a pale area was already discerned where the tract of I-Ielweg was expected to be located in the spinal cord and the medulla oblongata of the adult. Thus, the triangular or bandlike pale area was surrounded by those fiber tracts that were already myelinated at the periphery of the transition region between the anterior funicle and the lateral funicle of the spinal cord. The fiber tracts surrounding the pale area are considered to imply the reticulospinal, the vestibulospinal, the tectospinal and spinothalamic pathways. This pale area was followed cranially to the lateral part of the pyramis medullae oblongatae. The fibers of the anterior spinocerebellar tract were a little later in myelination than the fiber tracts mentioned above. This also applied to the fibertracts that were located in the area medial to the transition between the anterior and posterior spinocerebellar tracts and customarily considered to include the lateral spinothalamic tract, the spiiiotectal tract and the spinoreticular tract. Fine slightly stained myelinated fibers and medium sized myelinated fibers were observed with the rich background of unstained extremely fine fibers in this pale area. Both types of fibers were found all over the fiber tracts surrounding this pale area. Under higher magnification, it was seen that the caliber of the fine fibers was not so small as that of the extremely fine fibers which make the characteristic constituents of the tract of Helweg in the adult. These fibers are duly considered to develop into medium sized or larger fibers in the tract of Helweg in the adult (Figs. 2 and 3). I n the 7-, 8- and 9-month-old fetuses the tract of Helweg was always found, as it was in the 6-month-old fetus. The fine and medium sized myelinated fibers seemed to increaseinnumber in the area ofthe tract of Helweg, but the fine myelinated fibers were References p . I8ljI82

T A B L E 111 M Y E L O G E N E S I S OF T H E TRACTS I N THE S P I N A L CORD A N D

e o\

M E D U L L A O B L O N G A T A A T V A R I O U S S T A G E S OF H U M A N D E V E L O P M E N T * ~~

Tracts Goll’s fascicle Burdach’s fascicle Fasciculus posterior proprius Tr. spinocerebellaris posterior Tr. spinocerebellaris anterior Tr. spinothalamicus lateralis* * I Tr. spinotectalis** \ Tr. spinoreticularis* * Tr. pyramidalis lateralis Tr. rubrospinalis*** Tr. reticulospinalis*** lateralis I Tr. tectospinalis lateralis*** Fasciculus lateralis -~ urourius Larger fibers Fine fibers Tr. vestibulospinaliss Tr. spinothalamicus anterior5 I Tr. reticulospinalis anterior$ \ Tr. tectospinalis medialis Fasciculus longitudinalis medialis Fasciculus anterior proprius Tr. pyramidalis anterior Radix dorsalis Radix ventralis Radices spinales n. accessorii

6 Months

8 Months

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Newborn

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+-- +++ +++ -+ + -+++- +++

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14 years

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2 years

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* To describe the grade of myelination, the following scales were used: No myelin stained (-); Myelination just begun, but still very poor (&) : Generally faintly stained but well developed (+); With well developed myelin sheath, the thick myelin sheath with deep color (+ -); Just as in the adult (+++). * * The small area medial to the Tr. spinocerebel!aris anterior and the anterior portion of the Tr. sl:inocerebellaris posterior is considered to contain these tracts, but it is not possible to localize them individually. *** The more medial part to the previous area is considered to include these three tracts in this order from dorsal to ventral. 3 These tracts are considered to be localized in the anterior funicle medial and dorsal to the triangular tracts of Helweg.

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Fig. 2. C1 segment of the spinal cord of a 6-month-old fetus. Arrow indicates the triangular tract of Helweg. Weigert staining.

not so fine as the extremely fine fibers i n the matured tract of Helweg. The pale area of the tract of Helweg seemed to increase in size according to the growth of the spinal cord, and its dorsal boundary became more and more distinct as the myelination proceeded in the fiber tracts surrounding the pale area. At 10 months a small number of extremely fine fibers, which were stained slightly, appeared in the area of the triangular tract. At the same time a small number of large fibers was observed, fibers that were almost of the same caliber as large fibers in the triangular tract of the adult. The ‘diffuse formation’ was not yet distinct in the region comprising the anterior portion of the lateral funicle and the lateral portion of the anterior funicle. The extremely fine unstained fibers, which appeared yellowish and formed the background for the stained fibers, formed the characteristic component of the triangular tract of Helweg. Now 5 types of fibers, which were observed in the Helweg’s tract of the adult, could be identified in the area of the triangular tract: stained and unstained References p . IXljl82

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extremely fine fibers, fine, medium arid large fibers. The latter three types of fiber were observed scattered all over the tracts surrounding the triangular tract. The unstained extremely fine fibers were so abundant that the area of the tract of Helweg appeared conspicuous against the surrounding well stained tracts. The findings in the newborn were almost the same as in the previous stage (Figs. 4, 5, 6 and 7). At the stage of 2 years of age the extremely fine fibers that were stained increased i n number. They were, however, far less in number than in the adult tract. The pyra-

Fig. 3. Higher magnification of the triangular tract of Helweg in Fig. 2 (10 x 40).

midal tract was later in beginning myelination than the fiber tracts surrounding the tract of Helweg; the myelination began just before birth and reached its completion within one year thereafter (Figs. 8 and 9). In the spinal cord of a 14-year-old boy, the tract of Helweg had already the same appearance as that of the adult,

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Discussion It was reported in the results of Part I that the tract of Helweg is composed of 5 types of fibers; the unstained extremely fine fibers which make the ground substance of the tract, extremely fine stained fibers, fine, medium and large fibers.

Fig. 4. CI segment of the spinal cord of a 9-10-month-old fetus.

At the stages of from 6 to 9 months of age, Helweg’s tract is composed of unstained extremely fine fibers and fine and medium sized myelinated fibers. The extremely fine stained fibers were not yet observed at these stages. The stained fine fibers were not extremely fine like the extremely fine stained fibers in the triangular tract of the adult. They were also observed among the fibers surrounding the area of the triangular tract; hence they are considered to be in progress of development. The extremely fine fibers which appeared at the stage of 10 months were actually stained, and usually so fine that they had no lumina. They were very few in number at this stage, and gradually increased with age. At the newborn stage, the tract of Helweg was composed of a few extremely fine References p. Ibrl/I82

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Fig. 5. Higher magnification of the triangular tract of Helweg in Fig. 4 (10 x 40).

fibers, fine fibers, medium sized fibers and larger fibers, which were all well stained, being provided with a background of unstained extremely fine fibers. At the age of two years, the stained extremely fine fibers were not so abundant as they were in the adult. At the age of 14 years, they were found i n the same abundance as in the adult. Since the extremely fine fibers, unstained and stained, can be considered to be the principal component of the triangular tract, it is concluded that the myelination of the tract begins towards the end of fetal life and is completed in more than 2 years after birth. No other fiber tract is similar to the tract of Helweg in terms of the time of myelination; the fiber tracts surrounding the tract of Helweg are earlier and the pyramidal tract is later in myelination. As for the origin of fine, medium sized and large fibers intermingled in the tract of Helweg, fibers from those tracts which surround the area of the tiact have been considered. The area suriounding tbe tract of Helweg is already slightly myelinated at the stage of 6 months and is believed to include the spinothalamic tract, the reticulospinal tract, the tectospinal tract and the vestibulospinal tract. These tracts are composed ot those fine fibers and medium sized fibers which are found diffusely scattered in the area of the tract of Helweg at the stage of 6 months. Fibers from these tracts are

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Fig. 6. C1 segment of the spinal cord of a newborn.

considered to be the most probable origin of the larger fibers intermingled in the tract of Helweg. The fiber tracts which are located in the area medial to the transition region between the anterior and posterior spinocerebellar tracts are customarily believed to include the spinothalamic tract, the spinotectal tract and the spinoreticular tract, and they are a little later in myelination. So the spinothalamic tract could be exempted from the tracts which surround the triangular tract and could send fibers to the triangular tract. The anterior spinocerebellar tract was considered by Obersteiner (1901) as a possible origin of the larger fibers of Helweg’s tract. It is, however, a little later in myelination than the fiber tracts that surround the tiiangular tract. The medial tectospinal tract is one of the earliest tracts in myelination and situated too far away to be intermingled in the triangular tract. The lateral tectospinal tract may be one of the origins of larger fibers intermingled in Helweg’s tract. as Von Bechterew suggested. Summary The myelination of the spinal cord and the medulla oblongata was examined with speReferences p. 181/182

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Fig. 7. Higher magnification of the triangular tract of Helweg in Fig. 6 (I0 x 40).

cia1 reference to the histogenesis of Helweg’s tract on the fetuses of 6, 7, 8, 9 and 10 months, newborn, 2-year-old and 14-year-old patients. The following findings were obtained : ( I ) The extremely fine fibers of the tract of Helweg began to be myelinated at the age of 10 months, and the completion appeared to be later than 2 years after birth. (2) As far as myelination is concerned, the tract of Helweg is unique and has no analogous tract among other tracts in the spinal cord and the medulla oblongata. (3) From the coincidence of the time of myelination, the larger fibers intermingled in the tract of Helweg are presumed to have come astray from the adjacent descending fiber tracts, such as the reticulospinal tract, the lateral tectospinal tract and the vestibulospinal tract. P A R T 111. F I N D I N G S O F T H E T R I A N G U L A R T R A C T O F H E L W E G IN T H E P A T H O L O G I C A L M A T E R I A L

The case upon which the following study is based is that of a male patient aged 53, who died in February 1963 from a penis cancer in Tsu National Hospital. As the body of this patient was found accidentally among the cadavers stored for the dis-

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Fig. 8. CI segment of the spinal cord of a 2-year-old girl.

section of medical students at Mie Prefectural Medical School, the clinical history is not clear, except that he had difficulty in walking since the age of 16 years or so. There are numerous discrepancies in the findings on the degenerated tract of Helweg resulting from lesions of any kind in the brain stem or the lower level of the spinal cord. The reasons why the results are so diverse, are chiefly the following: ( 1 ) It is always difficult to obtain suitable materials which have localized lesions in the central nervous system. (2) As pointed out previously, the area of Helweg’s tract appears pale even in the normal spinal cord; this appearance has been misinterpreted as a degenerative change in the study of the tract in the past. (3) Besides larger fibers as the normal constituent of Helweg’s tract, other fiber tracts are sometimes located in the area of the tract. The degeneration of these fiber tracts could be misinterpreted as that of the triangular tract. The most frequent of these fiber tracts is the ventrolateral pyramidal tract of Barnes (Yamakawa, 1914). When the pyramidal tract is interrupted at the higher level of the brain stem, part of the degenerated pyramidal tract, which is situated in the area of Helweg’s tract as the ventrolateral pyramidal tract of Barnes, has been mistaken for the degeneration of References p. 181/182

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Fig. 9. Higher magnification of the triangular tract of Helweg in Fig. 8 (10 x 40). Weigert staining.

Helweg’s tract. The estimation of the lower limit of Helweg’s tract was always subject to this kind of misunderstanding. In spite of these difficulties, the findings on human pathological materials have always been the most valuable source of study featuring the tract of Helweg, since this tract has not been found with certainty in animals.

Materials and Mefhods The whole brain, including the pons, cerebellum, medulla oblongata and the spinal cord, was obtained for examination. Sections of 30 p thickness were stained by the Nissl and Weigert methods alternatively. The brain weighed 1190 g as a whole and the cerebellum alone weighed 90 g. Results

The study is still in progress, so only the major findings which are expected to have

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Fig. 10. The olivary niicleus of the normal brain. Nissl staining (10 x 5 ) .

some close relation with the triangular tract of Helweg will be discussed. The appearance of the olivary nucleus in the section stained by the Weigert method had no peculiarity. The most striking finding in this material was the disappearance of neurons in the olivary nucleus in the sections stained by the Nissl method. Besides a small number of normal looking neurons in the medial portion of the anterior lamella of the main olivary nucleus and small shrunken neurons scattered sparsely all over the nucleus, no normal neurons, which were usually found abundantly in the olivary nucleus, were recognized in the whole olivary nuclear complex, and only the glial elements were found packed in the area of the nucleus. The Purkinje cells in the cerebellar cortex were subject to high degeneration losing their normal contour. Their References p . I S l j l 8 Z

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Fig. 11. The olivary nucleus in a brain with olivo-cerebellar atrophy. Nissl staining (I0 x 5 ) .

characteristic arrangement in a row at the superficial zone of the granular layer was lost (Figs. 10 and 1 I). The tract of Helweg appeared to be quite normal under the lower magnification. It was a pale triangle with its angle directed centrally, and its base along the anterolateral surface of the spinal cord at the levels of CI and C2. The caudal limit could not be determined as the lower cervical cord was not available. At the higher level, the triangle was located along the lateral aspect of the pyramis and occupied the space surrounded by the pyramis, lateral tip of the medial accessory olivary nucleus, Gowers’ bundle and the surface of the spinal cord as in the normal spinal cord. It

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Fig. 12. Higher magnification of the triangular tract of Helweg in the normal brain (10 x 40). Weigert staining.

Fig. 13. Higher magnification of the triangular tract of Helweg in a brain with olivo-cerebellar atrophy (10 x 40). References p . 181/182

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Fig. 14. CI segment of the spinal cord of the olivo-cerebellar atrophy. Arrow indicates the triangular tract of Helweg. Weigert Staining.

disappeared at the level of the caudal third of the olivary nuclear complex. The fiber composition of the tract of Helweg showed no abnormality; the unstained extremely fine fibers were abundant and gave a clear figure of the tract being surrounded by the deeply stained adjacent fiber tracts (Figs. 14, 15 and 16). The extremely fine, fine, medium, and larger fibers, all well stained, were present in apparently similar proportions to those in the normal tract of Helweg. In addition, the ‘diffuse formation’ was very conspicuous in the area comprising the anterolateral aspect of the anterior horn, containing a great amount of unstained and stained extremely fine fibers (Figs. 12 and 13). The internal arcuate fibers from the olivary nucleus were less abundant than in the normal brain and faintly stained. Accordingly, the inferior cerebellar pedunculus was less in size than the normal. The central tegmental tract seemed to be less developed than usual, but this was not so conspicuous, considering that the brain as a whole was less developed than the normal. Neurons in the red nucleus were less in number than in the normal brain, and some of them seemed to be degenerated.

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Fig. 15. Medulla oblongata at the level of the pyramidal decussation in the same brain as in Fig. 14.

The atrophy of the pontine nuclei was not obvious. The motoneurons in the lower brain stem and the spinal cord were normal. The posterior funiculus, pyramidal tracts and the spinocerebellar tracts did not show any conspicuous abnormalities.

Discussion Thecase seems to belong to the olivo-cerebellar degeneration of Holmes ( I 907). Thus References p. 181/182

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Fig. 16. Medulla oblongata at the level of the caudal third of the principal olivary nucleus in the same brain as in Fig. 14.

the obvious atrophy was limited to the olivary nucleus and the cerebellum, while the pontine nuclei remained almost intact. It is surprising to see the typical tract of Helweg in the spinal cord and the medulla oblongata, whose olivary nuclear complex is highly degenerated, considering the traditional idea of the close relation between the oiivary nucleus and the triangular tract in terms of the origin or termination of the latter.

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Many investigators have claimed that the origin of the triangular tract is in the olivary nucleus. Careful studies of these past papers, however, reveal that no convincing evidence has been given for the notion that the tract originates from the olivary nucleus, as mentioned in the discussion of Part I of this paper. For instance, Von Bechterew (1901) presumed that the tract made one system together with the central tegmental tract having a relay station in the olivary nucleus. His opinion was baced upon the findings of Meyer ( I 882) that the tegmental tract, olivary nucleus and the triangular tract were found degenerated at the same time after a hemorrhage in the pontine tegmentum. This report of Meyer, however, was issued 5 years before the detailed description of the triangular tract by Helweg (1888), and it is not certain whether it dealt with the true triangular tract. Ransohoff (1902) reported the simultaneous degeneration of the triangular tract, the central tegmental tract, the pyramidal tract and the olivary nucleus after a malacia in the pontine tegmentum. Because the ventrolateral pyramidal tract of Barnes is the tract most frequently located in the area of the triangular tract, there is a possibility that the degeneration of the former was mistaken for that of the triangular tract. Antone and Zingerle (1914) suggested the close relation between the olivary nucleus and the triangular tract from the concomitant atrophy of both in an infant. The triangular tract was small in volume in this case, but it contained fibers that might have come, according to their opinion, from the higher level of the brain stem or that might be the ascending fibers. There are some reports of olivo-ponto-cerebellar atrophy where the triangular tract was found atrophied (Guillain et al., 1933; Noica et nl., 1936). These cases showed the concomitant degeneration of both the olivary nucleus and the triangular tract of Helweg. In these reports the triangular tract was only briefly referred to; and it is impossible to ascertain details about it. Because of the difficulty of proving the true degeneration of the triangular tract, these reports may be of little account. There are also some reports which did not prove any marked degeneration of the triangular tract, in spite of the occurrence of marked atrophy of the olivary nucleus. Obersteiner (1901) mentioned one case of cerebellar sclerosis where the olivary nucleus was highly degenerated and the triangular tract was intact. In his report a case of Jacobson Jamane was cited, which showed an intact triangular tract in spite of a degenerated olivary nucleus. The details, however, are not available in these reports. Therefore, the present report is significant in demonstrating definitely the normal triangular tract in the brain with atrophied olivary nucleus. The most important problem is the criterion on which the triangular tract is considered as normal. As stated in the previous part, the major and principal constituent of the tract is the group of extremely fine fibers, stained and unstained. The other larger fibers are considered to have come astray from the adjacent fiber tracts and they are not essential components of the tract. Special attention, therefore, was paid to the extremely fine fibers in the area of the triangular tract in this case and no obvious anomaly was found in their appearance. Tn view of the integrity of the triangular tract regardless of the highly atrophied olivary nucleus, it is permissible to conclude at least that the triangulartract of Helweg does not originate in the olivary nucleus. References p . I 8 l j I 8 2

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Summary The spinal cord and the medulla oblongata of a patient, who died from the olivocerebellar atrophy of Holmes, were examined with special reference to the tract of Helweg, and the following findings were obtained: (1) The olivary nuclear complex showed marked atrophy without any intact neurons, except in its small area comprising the medial tip of the ventral lamella of the left principal olivary nucleus. (2) The triangular tract of Helweg was found to be quite normal, as far as the fiber composition, position and the size of the area occupied by the tract in the upper cervical cord are concerned. (3) Accordingly, it was concluded that the triangular tract of Helweg did not originate in the olivary nucleus to descend the spinal cord. GENERAL DISCUSSION

As described in Part 1, the only certainty for the relation between the triangular tract and the olivary nucleus which can be observed in the normal preparation of Weigert staining is that the fibers of the triangular tract cannot be followed higher than the caudal third level of the main olivary nucleus. For the disappearance of the fibers of the tract at this level, two possibilities are considered. If the tract were the descending one, its fibers might have originated in the olivary nucleus or might have come down to the level of the olivary nucleus in the diffuse distribution from a higher level to be collected to descend in the spinal cord as the triangular tract. l n the latter case they should be collaterals of the tracts that originated at the higher level, considering the extraordinary thinness of the fibers of the triangular tract. The possibility that the tract originates in the olivary nucleus are disproved by the findings of Part 111. As the descending tracts which might have originated in the higher brain stem and could be followed down to the triangular tract, the central tegmental tract, the pyramidal tract, and those descending tracts surrounding the triangular tract is to be considered. The central tegmental tract which may continue to the triangular tract with or without the olivary nucleus as the relay station was presumed first by Helweg (1888). Later Von Bechterew ( I 901) mentioned this possibility citing the cases of Meyer (1 882). Observations of Moeli and Marinesco (1 892) and Ransohoff (1902) have been cited as evidence of the possible close relation between the central tegmental tract and the olivary nucleus. On the other hand Collier and Buzzard (1901) could not find any degeneration ofthe triangular tract, while the central tegmental tract was highly destroyed in their two cases of tumor in the region of the cerebral pedunculus. The poor central tegmental tract which coexist with the well developed triangular tract in this case does not seem to favor this assumption too. The frequent occurrence of degeneration in both the pyramidal tract and the tri-

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angular tract (Russell, 1898; Spiller, 1898; Mott and Tredgold, 1900; Collier and Buzzard, 1901 ; Kattwinkel and Neumaier, 1907) makes one think of the possible close relation between both. The degeneration in these cases, however, was not always certain, and is considered to be that of the ventrolateral pyramidal tract of Barnes, which is frequently located in the area of the triangular tract of Helweg (Yamakawa, 1914). Although the collaterals from the reticulospinal tract, the vesti bulospinal tract, the tectospinal tract and the spinothalamic tract can also be considered in this connection, there is no evidence for these. Obviously then, the evidence in the past which seemed to favor the descending direction of the tract is not convincing. The alternative is that the tract might be an ascending one. Investigators have claimed the ascending direction of the triangular tract from the study of their patholog. ical materials. Von Dydinski (1903) traced the degenerated fiber bundles in the anterior funicle of the spinal cord with the myelitis at the level of the thoracic spinal segn-ent. These fiber bundles were found scattered around the anterior roots in thoracic and lower cervical spinal segments and located laterally to the anterior roots. At the transition level from the spinal cord to the medulla oblongata, they moved dorsally to disappear at the level of the olivary nucleus. Goldstein (1910) reported two cases of tumors at the level of the C2 segment and the lumbar intumescence. He observed degenerated ascending fibers entering the olivary nucleus. As stated in Part 1, the triangular tract cannot be found at the lumbar segment and so the degenerated fibers would be those belonging to the ‘diffuse formation’ which is considered to be homologous to the triangular tract of Helweg. As for the origin of the ‘gesamte Formation’ (triangular tract plus ‘diffuse formation’) he presumed it to be in the anterior horn in agreement with Schwartz who actually observed fibers leaving the anterior horn and joining the triangular tract of Helweg. This opinion is in good accord with the findings that the triangular tract and the ‘diffuse formation’ are abundant in the area surrounding the anterior horn of the spinal cord. Now it seems most likely that the fibers of the triangular tract of Helweg originate in the anterior horn or elsewhere close to it, ascend the cervical cord up to the level of the olivary nucleus and then disappear there. Kaplan thought these fibers would originate in the small cells among large motoneurons in the anterior horn; some of them would terminate in the olivary nucleus and some would go into the cerebellum. By means of this connection the anterior horn would be connected with the cerebellum with or without the relay station in the olivary nucleus. Though clear evidence for the termination of the triangular tract of Helweg in the olivary nucleus was not obtained, it would be reasonable to consider that the majority of the fibers of the triangular tract enter the olivary nucleus, considering the amount of the fibers and the volume of the nucleus. The larger fibers intermingled in the triangular tract are considered, from the myelogenetic study, to have come astray from the fiber tracts surrounding the triangular tracts from the dorsal and medial borders. These fiber tracts are customarily believed to include the reticulospinal tract, the vestibulospinal tract, the tectospinal tract and the spinothalamic tract. As the spinothalamic tract can be excluded from the Refrrences p . 1811182

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possible origin of the larger fibers judging from the myelogenetic behavior, the larger fibers intermingled in the area of the triangular tract are considered to have come astray from the descending tracts surrounding the triangular tract from the dorsomedial border, such as the reticulospinal, the tectospinal and the vestibulospinal tracts. Therefore the triangular tract is considered to consist of two categories of fibers: ascending extremely fine fibers, stained and unstained, forming the principal component of the tract, and the descending larger fibers which are considered to have other origins. This concept is in good accord /with author’s observation (1955) that the larger fibers were observed degenerated and the fine fibers were intact in the spinal cord with a tumor in the pons and medulla oblongata. Kattwinkel and Neumaier (1907) had a different opinion for the direction of the fine fibers and larger fibers from the findings of the degenerated fibers in the spinal cord after a lesion in the cerebral peduncle: the descending fine fibers and ascending larger fibers. As pointed out previously, it is doubtful whether these fine fibers, which they observed to be degenerated, really belong to the triangular tract of Helweg. SUMMARY

Details of the triangular tract of Helweg were observed on the spinal cords and medulla oblongata of I8 patients. The myelogenesis of the spinal cord and the medulla oblongata was studied with special reference to the triangular tract of Helweg. One case of olivo-cerebellar atrophy was studied, and the survival of the normal triangular tract was observed regardless of the marked atrophy of the olivary nucleus. From these observations the following conclusions were obtained: (1) The triangular tract of Helweg was usually observed between the Ievels of the caudal third of the olivary nucleus and the C5 or C6 of the spinal cord. (2) The stained extremely fine fibers, which constitute the essential component of the triangular tract of Helweg, start their myelination just before birth and complete it later than 2 years after birth. (3) From the myelogenetic standpoint, the larger fibers intermingled in the area of the triangular tract are considered to have come astray from the adjacent descending tracts such as the reticulospinal tract, the tectospinal tract and the vestibulospinal tract. (4) Considering the well preserved triangular tract of Helweg in the spinal cord and the medulla oblongata with highly atrophied olivary nucleus in the case of the olivo-cerebellar atrophy, the triangular tract cannot be considered to originate in the olivary nucleus and descend to the spinal cord. (5) It seems most likely that the triangular tract originates in the anterior horn or its proximity and ascends to the level of the olivary nucleus to terminate there or elsewhere adjacent to it. A C K N 0 W L E D G E M E N TS

Grateful acknowledgement is due to Dr. T. Kanaseki, Professor of Anatomy at Mie Prefectural Medical College, for his generosity in permitting me to use his specimens of olivo-cerebellar atrophy which constitutes the major part of this paper, and to Dr. N. Mizuno in our laboratory for his kind help in preparing the photomicrographs.

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REFERENCES

G., AND ZINGERLF, H., (1914); Genaue Beschreibung eines Falls von beiderseitigem KleinANTONE, hirnmangel. Arch. Psychiat. Nervenkr., 54, 8-75. BARNES, S., (1901); Degenerations in heniiplegia : with special reference to a ventrolateral pyramidal tract, the-accessory fillet and Pick’s bundle. Brain, 24, 463-501. COLLLER, J.,-ANDBUZZARD, F., (1901); Descending mesencephalic tracts in cat, monkey and -man; Monakow’s-bundle; the dorsal longitudinal bundle; the ventral longitudinal bund1e;the pontospinal tractslatera1 and ventral; the vestibulo-spinal tract; the central tegmental tract (Zentrale Haubenbahn); descending fibres of the fillet. Brain, 24, 177-221. EDINGER, L., (1911); Vorlesungen iiber den Bart der nerviisen Zentraiorgane des Menschen und cler Tiere. Bd. 1 . Leipzig und Wien, Deuticke. GOLDSTUN, K., (1910); Ueber die aufsteigende Degeneration nach Querschnittsunterbrechung des Ruckenmarks (Tractus spinocerebellaris posterior, Tractus spinothalaniicus). Neurol. Zentralbl., 29,898-911. GUILLAIN, M. G., BERTRAND, I., ET~THUREL,-R., (1933);-Etude anatomoclinique d’un cas d’atrophie olivo-ponto-cerebelleuse-avec symptbmes pseudo-bulbaires. Rev. neurol., 11, 138-154. HELWEG, H., (1888); Studien iiber den centralen Verlauf der vasomotorischen Nervenbahnen. Arch. Psychiat.-Nervenkr., 19, 104-183. HOLMES, G., (1907); A form of familiar degeneration of the cerebellum. Brain, 30, 466-489. KAPLAN,M., (1916); Ueber die Beziehung der Ursprungskerne der motorischen Nerven zu den supraponierten Zentren. Arbeiten aus dem Neurologischen Innstitut an der Wiener Universitat, 21, 383-422. W., AND NEUMAIER, C. L., (1907); Ueber den Verlauf der sog. Helwegschen DreiKATTWINKEL, kantenbahn oder Bechterews Olivenbundel (Fasciculus parolivaris). Dtsch. Z . Nervenheilk., 33, 229-231. MASUDA, S . , (1963); On the Helweg’s triangular tract and the Barnes fasciculus in the human brain. Jap. . I . Anat., 38, 52 (in Japanese). MEYER, P., (1882); Ueber einen Fall von Ponshamorrhagie mit secundarer Degeneration der Schleife. Arch. Psychiat. Nervenkr., 13, 63-98. MOELI,P., U N D MARINESCO, C., (1892); Erkrankung in der Haube der Brucke mit Bemerkungen uber den Verlauf der Bahnen der Hautsensibilitat. Arch. Psychiat. Nervenkr., 24, 655-692. A. F., (1900); Hemiatrophy of the brain and its results on the cereMOTT,F. W., AND TREDGOLD, bellum, medulla and spinal cord. Brain, 23,239-263. J., ET BANU,E., (1936); Contribution a l’etude de I’atrophie olivo-pontoNOICA,D., NICOLESCO, cerebelleuse. Rev. neurol., 66, 285-306. OBERSTEINER, H., (1901); Ueber das Helweg’sches Bundel. Neurol. Zentralbl., 20, 546-549. OGAWA,T., (1943); Does the Helweg’s triangular fasciculus exist in animals except man? Med. Biol., 4, 562-566 (in Japanese). OKAMOTO, M., KUSAKA, H., KATAYAMA, Y . ,AND HATTORI, I., (1955); Supplemental findings on the human Helweg’s triangular tract. Arbeiten aus dern Anatomischen Institiit der Mie Universitat, 3, 1-10 (in Japanese). PICK,A., (1898); Ueber ein w n i g beachtetes Fasersystem (von Bechterew’s ‘Olivenbiindel’, Helweg’s ‘Dreikantenbahn’). Beitrage zur Pathologie und pathologischen Anatomie des Centralnervensystems. Berlin, Karger. POLLAK,F., (1935); Anatomie des Ruckenmarks, der Medulla oblongata und der Brucke (Pons). Handb. Neurol., 1, 265-424, Berlin. RANSOHOFF,A., (1902); Ueber einen Fall von Erweichung im dorsalen Teil der Briicke. Arch. Psychiat. Nervenkr., 35,403429. REINHOLD, G . ,(1897); Beitrag zur Kenntnis der Lage des vasomotorischen Centrums in der Medulla oblongata des Menschen. Dtsch. 2. Nervenheilk., 10,67-142. RUSSELL, R., (1898); Contribution to the study of some of the afferent and efferent Lracts in the spinal cord. Brain, 21, 145-179. SCHWARTZ, L., (1916’); Untersuchungen uber die HelwePsche Dreikantenbahn. Arbeifen aus den2 Neurologischen Institut an cler Wiener Universitat, 21, 325-332. SPILLER, W. C., (1898); A contribution to the study of secondary degeneration following cerebral lesions. J . nerv. ment. Dis., 25, 1-19. SPILLER,W. C., (I 902); Ueber den directen ventrolateral Pyramidenstrang. Neurol. Zentralbl., 21, 534-536.

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THALBITZER, S., (1910); Helweg’s Dreikantenbahn in der Medulla oblongata. Arch. Psychiat. Nervenkr., 47, 163-195. VONBECHTEREW, W., (1894); Ueber das Olivenbundel des cervicalen Theiles vom Ruckenmark. Neurol. Zbl., 13, 433437. W., (1895); Ueber ein besonders im vorderen Teil des Seitenstrangs des RuckenVONBECHTEREW, marks verlaufendes Biindels langer Fasern. Neurol. Zentralbl., 4, 155-1 56. W., (1899); Die Leitungsbahnen im Gehirn und Ruckenmark. Leipzig, UniversitatsVONBECHTEREW, Verlag, p. 397. VONBECHTEREW, W., (1901); Ueber ein wenig bekanntes Fasersystem an der Peripherie des anterolateralen Abschnittes des Halsmarkes. Neurol. Zentralbl., 20, 194-1 97. VON DYDINSKI, L., (1903:; Ein Beitrag zum Studium des Verlaufs einiger Ruckenmarksstrange. Neurol. Zentralbl., 22, 898-910. E., (1937); Die zentrale Haubenbahn als ableitende Bahn des extrapyramidalmotoriWEISSCHEIDEL, schen Systems. Z. ge5. Neurol. Psychiat., 158, 264272. S., (1914); Zur Kenntnis der ventrolateralen Pyramidenbahn Barnes’ und der DreiYAMAKAWA, kantenbahn Helwegs. Bemerkungen zur Frage der Leitungsbahn im lateralen Markfeld der Olive und in der anterolateralen Ruckenmarksperipherie. Mitteilunqen aus der Medizinixhen Fakultiit der Kaiserlichen Universitat zu Tokvo, 11, 1-55. ZIFHEN, TH., (1913); Anaromie des Cenrralnervensystems. Jena, Fischer.

183

Multiple Sclerosis and Allied Diseases in Japan: Epidemiological and Clinical Aspects SHIGEO O K I N A K A

AND

YOSHIGORO K U R O I W A

Toronomon Hospifal, Tokyo (Jopon) and Neurological Institute, Faculty of Medicine, Kyushu University, Fukuoka (Japan)

INTRODUCTION

Demyelinating encephalomyelitis, especially multiple sclerosis and allied disorders, are known to show characteristic geographical distributions and are most prevalent in the temperate zones of the world, and have low rates in the tropical and subtropical areas (Kurland, 1964). There are various speculations on the etiology suggesting geographical climatic factors (Kurland, 1964) or racial predisposition or auto-immune hypotheses. In Japan, it has been postulated that multiple sclerosis is almostnon-existent(Miura, 1911; Shimazono, 1931, 1932), and neuro-pathologists also insist that there are no typical autopsied cases compatible with multiple sclerosis. Our previous investigations on the collection of cases from major hospitaIs throughout Japan (Okinaka, Tsubaki, Kuroiwa, Tokyokura, Imamura and Yoshikawa, 1958) revealed the following results: among 270 cases of demyelinating diseases 66 cases were compatible with multiple sclerosis clinically and 175 were neuromyelitis optica or optic spinal type of multiple sclerosis. Although this material did not represent the whole population of the Japanese, and possibly had statistical biases, the high frequency of optic spinal vulnerability was notable. Two autopsy cases were included in this report: one case was an intermediate form between multiple sclerosis and neuromyelitis optica. However, both cases showed severe necrotic changes in the optic chiasma and spinal cords with minor lesions in the other neuraxis. The pathological pictures were more compatible with severe demyelinating encephalomyelitis than typical multiple sclerosis. As to the pathological studies ofdemyelinating diseases of the Japanese, Shiraki (1961) has made a summarized report including these two cases. HOSPITAL STATISTICS

In England, northern Europe and northern United States, the ratios of multiple sclerosis among neurological admissions were about 10% or less; and Woods (1929) reported a percentage of 1.5 in China. Our surveys (Okinaka et a/., 1958) in Tokyo and Kyushu Universities showed about 0.7-0.9 "/o among the organic neurologic admissions. These figures may indicate that (1) there are less multiple sclerosis cases References p . 191

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among the Japanese, and (2) the relative frequency of the disease in the total neurological disorders is lower than those of the northern United States and Europe. P O P U L A T I O N S U R V E Y S I N S E L E C T E D CITIES

Since the above-mentioned data do not show the absolute frequencies of the disease, an epidemiological survey of selected populations in Japan was planned (Okinaka et al., 1960) with the assistance of the National Institute of Neurological Diseases and Blindness", with the aim of determining the prevalence and incidence of the disease, and obtaining the clinical features of demyelinating diseases of the Japanese. It was also planned to study the effects of climatic and geographical factors since Japan extends a long way from north to south. S E L E C T I O N O F P O P U L A T I O N FOR T H E S U R V E Y

In order to obtain comparable data, cities with similar size and medical facilities were selected for the epidemiological survey. Each has at least one medical school serving as the local medical center, which was available to the survey center. Sapporo city in Hokkaido island (latitude 43" N), Niigata on the mainland (38" N), and Fukuoka and Kumamoto in Kyushu island (33" N) were chosen for such purposes (Table I, Fig. 1). TABLE I CHARACTERISTICS OF CITIES SURVEYED

Kurnamoto

Fukuoka

Niigata

Sapporo

-~

Latitude 33"N 33"N 38"N 43% Population 332,000 608,000 230,000 426,000 Mean temperature (January 45.1 (7.3) 42.0 (5.6) 36.1 (2.3) 22.1 (-5.5) /July 77.3 (25.2) 82.0 (27.8) 74.7 (23.7) 59.9 (15.5) Number of practitioners 108 74 84 82 (per 100,000)

PROCEDURES OF THE SURVEY

The survey included co-operation by 5 universities of Japan: Tokyo University (Prof. Okinaka, as the chairman of the survey), Kyushu University in Fukuoka (regional director, Prof. Katsuki), Kumamoto University (Prof. Miyagawa), Hokkaido University in Sapporo (Prof. Suwa) and Niigata University (Prof. Ueki). These regional directors arranged the case collection. Drs. Kurland and Kuroiwa planned the project and the co-ordination of these groups. As neurologists, Drs. D.

* Chief of Epidemiology Branch, L.T. Kurland.

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185

McAlpine (Kumamoto and Sapporo survey), H. H. Reese (Fukuoka survey), and S. Araki (all surveys) were appointed to make the final diagnoses. Survey procedures similar to those employed in other countries were adopted in the hope of achieving results which could be compared statistically. Efforts were made to locate and examine all patients who were bona fide residents and had been observed or treated during the last 5-year period: from 1953-1959 inclusive for Kumamoto and Sapporo, from

JAPAN

Fig. 1. Location of selected cities in this survey.

1954-1958 for Fukuoka, and 1955-1960 for Niigata. For the preliminary case finding the following groups of diagnoses were included ; multiple sclerosis, neuromyelitis optica, retrobulbar neuritis, acute disseminated encephalomyelitis, spastic paraplegia, spinal syphilis, spinocerebellar degeneration, motor neuron disease, polyneuritis, and ocular palsy of undetermined origin. Method of collecting cases Collection of the cases was done from the hospital records of the major hospitals (departments of internal medicine, neuropsychiatry, orthopedics, pediatrics, ophthalmology). Senior medical students or staff of the regional directors helped in reviewing the hospital records. Inquiries to practitioners in the city were sent from the regional directors explaining the purpose of the project and asking whether they had observed any cases with the diseases listed. The responses from these inquiries were excellent (97 %-lo0 %). The records of suspected cases were reviewed by the neurologists assigned who examined as many cases as possible. Cases with unknown addresses or non-residents were excluded from the provisional cases (Table 11), and most of the residual cases were examined by the neurologists. Epidemiological analysis was made of the examined cases, and the prevalence rates were calculated at the end of the 5 year period as mentioned. References p . 191

186

S. O K I N A K A A N D Y. K U R O I W A

T A B L E I1 DISPOSITION OF C A S E F I N D I N G S -~

~

~~

Fukiroka

Niigata

500,000 5500 341

300,000 6000 386

112 76

192 149

287

75

133

265

3

1

8

8

8

19

Kumamoto Sapporo

Hospital records reviewed Neurologic records collected Provisional cases Discarded (non-resident, not located, etc.) Residual cases Examined Conclusive history of demyelinating diseases Demyelinating diseases confirmed by examination

117 61

56 53

~

99

12

RESULTS

The classification of provisional cases is shown in Table 11. In Fukuoka city, for example, about 500,000 hospital records were reviewed and 5500 neurological disorders were extracted as the first step. Out of these, after reviewing, 341 cases were selected as provisional. Out of these, 192 had unknown addresses, were dead, or for other reasons were discarded. Residual cases were 149, and 133 were examined neurologically. Classification of cases of multiple sclerosis

Due to lack of specific diagnostic tests for multiple sclerosis, the clinical diagnostic criteria were divided into three categories. Early probable: cases in which the history strongly suggested a diagnosis of multiple sclerosis but in which there was as yet little or no disability and few neurological signs. Probable: cases in which there seemed little doubt about the diagnosis. Possible: cases in which there were physical signs compatible with multiple sclerosis, but some doubt existed on the diagnosis.

Diagno.rtic categories of deniyelinating diseases

In Table 111, diagnostic categories of the cases at the final step are shown. In total there were 32 cases with multiple sclerosis, 4 with neuromyelitis optica and 23 with acute disseminated encephalomyelitis. The ratio of multiple sclerosis to neuromyelitis optica was 8 : I , which suggested a slightly higher ratio than in western countries, where neuromyelitis optica is usually 1 % or less of the multiple sclerosis group of diseases.

_

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MULTIPLE SCLEROSIS A N D ALL1 E D DISEASES

TABLE I11 D I A G N O S T I C C A T E G O R I E S OF DEMYELINATING

DISEASE

Multiple sclerosis probable Probable

Fukuoka Niigata Kumamoto Sapporo Total

1 6 2 1

10

Possible

6* 2 2* 0 10

4 1

Total

Neuromyelitis optica

All

A.D.E.M.

CasCs

3 4

1 0 1 2

15 3 3 2

27

9 7 5

12

32

4

23

59

11

12 11

9

* One of them was verified by autopsy. Age of onset

Age of onset for multiple sclerosis is shown in Fig. 2, indicating a peak in the twenties. The age of onset for retrobulbar neuritis showed a similar curve but the peak was in the teens. Prevalence and annual incidence rates

The prevalence rates for multiple sclerosis (neuromyelitis optica included) in these cities were about 2-4 per 100,000 population (Table IV), which are evidently lower

-

Multiple sclerosis Aetrobulbar neuritls *---

in years

Fig. 2. Age of onset of multiple sclerosis.

than those in the United States and Canada or northern Europe. The annual incidence rates were about 0.3-0.4 per 100,000population in these cities. There was no difference between the northern and southern cities. Clinical features

( I ) Initial symptoms Blurred vision (29 %), weakness in limbs (23 %), numbness or paresthesia (23 %) References p . 191

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S. O K I N A K A A N D Y . K U R O I W A

TABLE IV M U L T I P L E S C L ER O S I s ( I N c L U D I N G

N Eu R O M Y E L I T I s O P T I c A ) P R E v A L E N c E A N D INCIDENCE RATES

Number of cases Prevalence per ,for prevalence IOO,OOO popitlation Incidence

Fukuoka Niigata

Kumamoto Sapporo

608,000 230,000 332,000 426,000

lo 9 6

I

1.6* 3.9** 2.45 1.65

0.3 0.4 0.3 0.3

* 1 Jan. 1959 * * 1 Jan. 1960 8 1 Jan. 1958

were major symptoms at onset. Following these, gait difficulty (17 %), pain (14%), sensory loss (9 %), and facial palsy (4 %) were noted at onset.

(2) Symptoms seen during the course Blurred vision (68 %) was first, followed by numbness (60 %), gait disturbance (51 %), weakness of the lower limbs (48%), of the upper limbs (29%), sensory loss (26 %), dysphagia (26 %), speech disturbance (23 %), double vision (2073, headache (20%) and neuralgic pain in trunk (14%). Mental symptoms were only 3 %. ( 3 ) Signs seen during the course As shown in Table V, pyramidal sign (7473, visual loss and disturbance in gait were the major signs. Optic atrophy was seen in about one third of the cases. Cerebellar signs were not common. These symptoms and signs indicated lesions of the spinal cord in 60% and of the optic nerves in 57%. Brain stem signs such as ocular palsies, or bulbar signs were seen in 37%. Cerebral or cerebellar signs were less frequently seen (6% each). A sensory positive sign, Lhermitte’s sign, was seen in only one case in this series.

( 4 ) Clinical types Cases which showed affectation of both predominantly optic nerves and spinal cord were most common (optic spinal): these included 4 cases of Devic’s disease and 7 cases of multiple sclerosis. Following this, optic brain stem or predominantly spinal types were common. Optic brain stem--spinal type is similar to optic spinal. There was no case of predominantly cerebral t j pe:(Table VI). Thus there were 13 cases with optic spinal lesions (optic brain stem spinal inclusive): optic nerve signs were mostly bilateral (except 2 cases) and spinal cord signs were marked transverse myelitis in the majority of the cases (10 out of 13). In 4 cases transverse myelitis and bilateral optic neuritis occurred simultaneously or in succession within a few weeks. In others the courses were with remissions and relapses. The latter should be diagnosed as optic spinal type of multiple sclerosis.

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189

TABLE V SIGNS OBSERVED D U R I N G THE COURSE OF DISEASE

Total

%

26 20 17 13 12 3 12 10 7 9 6 5 4 4 2 1

14 57 48 37 34 9 33 29 20 17 17 14 12 12 6 3 3

Pyramidal sign Visual loss Gait disturbance Sensory loss Optic atrophy Papilla swelling Sphincter disturbance Paraplegia Speech disturbance Ataxia Nystagmus Quadriplegia Abducens palsy Facial palsy Ocular palsy (111, IV) Mental sign Lhermitte’s sign

I

( 5 ) Course of the disease

63 % of the cases took courses with remissions and exacerbations and 17 %showed remission, 9 % progressive, 9 % stationary, and 3 acutely progressive. DISCUSSION A N D CONCLUSION

There have been epidemiological surveys on multiple sclerosis in various parts of TABLE V I CLASSIFICATION OF MULTIPLE SCLEROSIS A N D ALLIED DISEASES

Optic spinal Optic brain stem Spinal (mainly) Cerebro-optic Optic brain stem-spinal Brain stem-spinal Optic (mainly) Mixed Brain stem-cerebellar Brain stem- cerebello-spinal Brain stem Unknown Cerebral References p . 191

11 6 5 2 2 2 2 2 1 1

I 1 0

31

17 14 6 6 6 6 6 3 3 3 3 0

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the world, revealing that the disease is more prevalent in the temperate zones. The prevalence rates in the northern United States were about 50 per 100,000 population, and higher than those in the southern cities (Kurland, 1964). In Asian districts our survey is the first systematic epidemiological study revealing the prevalence rates of about 2-4 per 100,000 population (Okinaka et al., 1960). Although these figures are minimal values, still the prevalence in Japan is indicated to be very low compared with the northern United States or Europe. There was no difference between northern and southern cities in Japan. These did not confirm other surveys in the western countries showing differences between temperate and subtropical areas. The explanation needs future study. A second feature was the relatively high ratio of optic spinal vulnerability. There was a gradual transition from Devic's disease to multiple sclerosis. Some of the autopsied cases showed necrotic optic chiasma and necrosis in the spinal cord, which were clinically more compatible with multiple sclerosis than with Devic's disease. This may indicate that the Japanese cases were different from classical multiple sclerosis or there may be some constitutional factors which modify the demyelinating processes of the Japanese. Kurland postulated that these differences were rather associated with climatic and geographical than with racial or national origin. Barlow found a good correlation between geomagnetic latitude and rate of multiple sclerosis. The geomagnetic theory (Barlow, 1960) fits the low rate in Japan better than the simple geographic latitude theory. The low rate in Japan suggests other factors than merely geographical ones. Georgi and Hall made a comment on their Swiss survey that it is not climatic factors alone that are responsible for the relative prevalence of the disease in individual districts. They suggested a search for geological factors such as trace elements. SUMMARY

( I ) Four cities (populations about 230,000-600,000) in various latitudes (43" N to 33" N) were surveyed as to the morbidity of multiple sclerosis and allied diseases. ( 2 ) The prevalence rates were about 2-4 per 100,000 population in each city, and no difference was found between northern and southern cities. Thus the prevalence of multiple sclerosis is very low in Japan. (3) The clinical assessment showed that the optic spinal type was most common, with marked vulnerability of the optic nerve and spinal cord among the Japanese cases. (4) Devic's disease appeared to be more prevalent among the multiple sclerosis group of diseases in Japan. ACKNOWLEDGEMENTS

The authors wish to thank the staffs of the 5 universities, especially the regional directors Professors Katsuki, Miyagawa, Ueki and Suwa (in alphabetical order), and neurologists Drs. D. McAlpine, H. H. Reese and S. Araki, for their excellent collabo-

MULTIPLE SCLEROSIS A N D ALLIED DISEASES

191

ration. We are very much indebted to Dr. L. T. Kurland for his kind suggestions and interest in the Project. This study was supported by the U.S.P.H.S. Grant No. B. 2386. REFERENCES BARLOW, J., (1960); Correlation of the geographic distribution of the multiple sclerosis with cosmicray intensities. Acta psychiat. scand., 35, Suppl. 147. GEORGI, F., HALL,P., AND MULLER, H. R., (1961); Zur Problematik der mulriplen Sklerohe. Basel and New York, Karger, pp. 111-116. KURLAND, L. T., (1964); Geographic and climatic aspects of multiple sclerosis. Anier. J . pub. Hth, 50,588-597. MIURA, K., (1911); Discussion to M. Nonne and W. Holzmann, Serologischeszur multiplen Sklerose; speziell iiber die Cobra-reaktion bei multiplen Sklerose, D t x h . Z . Nervenheilk., 41, 123-146. s.,TSUBAKI, T.,KUROIWA, Y . , TOYOKURA, Y . ,IMAMURA,Y.,AND YOSHIKAWA, M., (1958); OKINAKA, Multiple sclerosis and allied diseases in Japan; clinical characteristics, Neurology, 8, 756-763. S., MCALPINE, D., MIYAGAWA, K., SUWA,N., KUROIWA, Y., SHIRAKI, H., ARAKI,S., OKINAKA, AND KURLAND, L. T., (1960): Multiple sclerosis in Northern and Southern Japan. Wld Neurol., 1, 22-42. J., (1931); B-Avitaminose und Beriberi U.S.W. Ergebn. inn. Med. Kinderheilk., 39, 1-68. SHIMAZONO, J., (1932); Discussion on multiple sclerosis. J.jup. SOC.int. Med., 20, 797-798. SHIMAZONO, SHIRAKI, H., (I 961); The present status of demyelinating encephalomyelitides of unknown origin from the pathoanatomical viewpoint in Japan. Clin. Neurol., 1(2), 107-1 28. Woons, A. H., (1929); The nervous diseases of the Chinese. Acrapsychiar. scand., 21, 542-570.

192

Behavioral Aberrations in Methamphetamine-intoxicated Animals and Chemical Correlates in the Brain HIROSHI UTENA Department of Neiiropsycliiutr.v, Cunrnn Universit.v School o.f Medicine, Maebashi (Japan)

Long-lasting behavioral change without apparent structural change in the brain presents a challenging problem to workers in neurobiology. Schizophrenia, a representative functional psychosis, is the core of the problem. The main difficulties of the biological approach to schizophrenia are to be found i n the complexity of clinical pictures, the lack of definition in behavioral terms, and the impossibility of experimentation on animals. It has long been known that behavioral changes of various duration can be produced by some kinds of drugs, which thus provide valuable tools for elucidating the mechanism of development of behavioral changes. In this respect, the significance of amphetamine or methamphetamine psychosis as a special type of model psychosis has been recognized by several authors (Utena et al., 1955; Tatetsu et al., 1956; Connell, 1958). Psychosis associated with methamphetamine usage was seen on a large scale in Japan and created a serious social problem during the post-war period culminating in 1953. Stimulated by this experience, systematic studies on chronic methamphetamine intoxication have been undertaken, especially in the laboratories of the Matsuzawa Mental Hospital in Tokyo and in the Department of Neuropsychiatry, Gunma University School of Medicine. At the beginning of the investigation, the blood level and the excretion into the urine of methamphetamine after the drug had been taken were determined in addicts and in normal volunteers. The tissue distribution of methamphetamine was also examined in acute and chronic experiments on guinea-pigs (Utena et a]., 1955). Then, metabolic studies were made of brain tissues of guinea-pigs, and it was found that the aerobic and anaerobic glycolytic activity in vitro decreased significantly after the longterm administration of methamphetamine. These findings were compatible with those observed in biopsy specimens taken from methamphetamine psychotics at the time of lobotomy operations (Utena and Ezoe, 1951). However, the functional meaning of these findings continued to be obscure, so that detailed studies both of the behavioral aberrations induced by the intoxication and of the chemical changes in the brain in in vivo conditions were needed. This report describes the results of studies on the following subjects: ( I ) the peculiarities in the clinical features of methamphetamine psychosis, (2) the behavioral

STUDIES O N METHAMPHETAMINE INTOXICATION

193

aberration of animals induced by the long-term administration of methamphetamine, and (3) the neurochemical correlates of behavioral changes. P E C U L I A R I T I E S IN T H E C L I N I C A L F E A T U R E S O F METHAMPHETAMINE PSYCHOSIS

As is well known, amphetamine or methamphetamine in a single therapeutic dose has a stimulative effect, while the drug in a chronic usage can produce a psychotic state. The clinical picture of amphetamine or methamphetamine psychosis is primarily a paranoid psychosis with ideas of reference, delusions of persecution, and auditory hallucinations, in a setting of clear consciousness. The mental picture may be indistinguishable from acute or chronic schizophrenia. There are marked differences between the methamphetamine psychosis and other types of drug psychoses, such as those induced by LSD-25 and mescaline. The pathological experiences produced by LSD-25 or mescaline are similar to those in dreams or delirium, with visual hallucinations, all of which occur only rarely in methamphetamine psychosis.The latter develops only in the chronic stage of intoxication and not in the acute stage, as do other model psychoses. Moreover, some behavioral symptoms of methamphetamine psychosis frequently remain long after a patient stops taking the drug. In most of our cases, the apparent psychotic symptoms subsided in a week or a month, whereas a loss of initiative and an emotional flattening or apathy persisted much longer, for several months or even over a year. This residual syndrome seems to be different from the so-called withdrawal syndrome, which is rather weak in this type of addiction, occurring only in a form of somnolence and adynamia of short duration (Table I) (Tatetsu et al., 1956). Another peculiarity in the residual state is a tendency for earlier symptoms to recur, which are usually induced by some kind of stress, either physical or psychological. Such tendency to relapse was found in one fourth of residual cases who were admitted to the Matsuzawa Mental Hospital. Compared with other kinds of intoxication psychoses, this is really an unusual phenomenon, since the causative agent no longer exists and an enhanced vulnerability alone remains. In a small proportion of patients the disorder took a deleterious course and eventually developed into a protracted schizophrenia-like state. Of all the cases in the Matsuzawa Mental Hospital, about 5 % belonged to this group. It seems too simple an explanation to say that these protracted psychotic cases should be diagnosed as having been schizophrenic from the beginning. According to Goto (1960) and Ariyasu (1964), this condition can be differentiated from typical schizophrenia by better rapport and emotional response in the former. This view was questioned by other investigators. There is no means to solve the diagnostic controversy at present. Considering the fact that the methamphetamine psychosis shows schizophrenia-like pictures at the onset of the illness, frequently has residual states and a peculiar tendency to relapse, it is highly probable that the intoxication may play some causative role in producing the long-lasting schizophrenia-like symptoms. References p . 2061207

194

H. U T E N A

TABLE I P S Y C H I C A N D B E H A V I O R A L S Y M P T O M S OF M E T H A M P H E T A M I N E PSYCHOTICS

The numbers express percentages of symptoms observed in 74 patients in the Matsuzawa Mental Hospital (Tatetsu er al., 1956). Symptoms

At the time admissior

One month after admission

Volitional disturbances: dull, idle inactive, stuporous restless, hyperactive

68 45 38

73 45 22

Emotional disturbances: elated depressed shallow, apathetic irritable anxious

24 15 51 51 43

45 14 75 24

Hallucinations and delusions Thought disorders

68 24

12 9

of ___

~.

These clinical considerations led the author to study the effect of the long-term administration of methamphetamine on the behavior of animals and to investigate a possible change in the metabolism and function of the brain of the intoxicated animals. THE BEHAVIORAL ABERRATION OF ANIMALS I N D U C E D B Y THE LONG-TERM ADMINISTRATION OF METHAMPHETAMINE

Experiments on guinea-pigs The first observation of behavior was made with guinea-pigs. The animals, which were injected subcutaneously with methamphetamine HC1 in a daily amount of 6 mg/kg for 20 to 70 days, showed a marked change in behavior. They became less active, lost the timidity which characterizes the behavior of this species, and became passive to handling (Utena et al., 1959). Experiments on mice A more quantitative study of behavior was carried out with mice. By the use of the revolving activity wheel, one revolution of which corresponds to a half meter run, the spontaneous running activity of male adult mice of the dd-strain was measured (Utena and Takano, 1960). Methamphetamine HCl i n a dose of 2.8 mg/kg caused a marked motor excitement which lasted for about 4 hours after the injection. The total activity on the day of treat-

STUDIES ON METHAMPHETAMINE INTOXICATION

195

ment was found to have increased significantly when compared with that under nontreated conditions, but for a few days subsequent to the day of injection the motor activity was much reduced. This effect of after-depression appears to be peculiar to methamphetamine, since no comparable effects could be obtained with other excitants such as methylphenidate, pipradrol and caffeine. In the chronic experiment, 1.4 mg/kg of methamphetamine HCI was given daily for 3 to 4 weeks. The animal was kept in a revolving wheel throughout the experiment, and measurements were made before, during and after the period of drug injection. The daily amount of the running activity increased slightly at the early stage of the injection period, but later decreased markedly. The reduction in motor activity persisted long after the cessation of the drug injection, and it required about 10 weeks for complete recovery. This reduction in the motor activity cannot be ascribed to ataxia or exhaustion, since the mean running velocity, which was measured also by the wheel, remained almost unchanged throughout the course of the experiment. The ratio of night to daytime activity of the intoxicated mice was found to have decreased from the normal value of 4 to less than 1. This shows that the animals lost their nocturnal habits, or the diurnal cycle of normal activity was seriously impaired (Utena and Takano, 1960) (Fig. I). No. o f

-Methornphetamine

rev.

1.4 rng/kg Veioci ty per rnin

1o.oc:~ . 5000

.i -.:I0 -20 -10

0

10

20

30

40

50

60

days

Methamphetamine 1.4 rng/ kg Chforpmrnazinc 6.0 mgfkg

-

Velocity

Fig. I . Reduction in motor activity of mouse induced by methamphetamine intoxication and counteractive effect of chlorpromazine. In the upper Fig., each bar expresses a daily amount of running activity, and the solid line a mean running velocity. The period of drug administration is indicated above. In the lower Fig. is shown a depressant effect of chlorpromazine on activity of normal mouse, and in the middle Fig. a counteractive effect of chlorpromazine on motor depression of methamphetamine-intoxicated mouse. References p. 306/207

196

H. UTENA

The intoxicated mice seemed to behave dully and sluggishly, but under certain conditions they even showed an exaggerated activity. A mouse which was intoxicated in an ordinary home cage responded to an unaccustomed wheel with an increased running activity for the first 2 or 3 days, and then gradually became dull. Contrary to this, a normal mouse responded to the wheel with less activity at the start, and it required a few days to reach a steady full activity (Shimizu, 1961). In attempts to obtain effective drugs for counteracting the motor depression induced by the chronic methamphetamine intoxication, it was found that chlorpromazine relieved this type of motor depression, although it had a depressant effect on the normal mouse. In contrast to chlorpromazine, psychic stimulants, such a s methamphetamine itself, methylphenidate and pipradrol, had no restorative effect on the motor depression or the effect was only transitory (Utena, 1961) (Fig. I). Experiments on rats

Yagi (1963) made an activity study similar to the above experiments on rats and confirmed that long-lasting reduction in revolving activity was produced by chronic methamphetamine administration. However, he noted that the intoxicated rats showed a normal or increased exploratory activity when examined by the open-field method. Moriguchi (1 963) studied avoidance learning in methamphetamine-intoxicated rats, and found that the acquisition as well as the extinction of learning required more time in these animals than in the controls. The prolongation of these processes was observed even one month after the cessation of the drug administration. This finding was interpreted as showing that chronically intoxicated rats are in a constant state of fear. The ‘cloister’ method The observations up to this point indicate that the responsive activity and the adaptive mechanism in behavior were changed somehow in the intoxicated animals. So, a more elaborate technique was needed for the study of behavior particularly in this respect. The ‘cloister’, which was designed by Hirao (Utena and Hirao, 1964; Hirao and Utena, 1965), was used for this purpose. The ‘cloister’ is a circular runway with a circumference of two meters, 6 cm wide and 6 cm high, and consists of 20 sectors of equal length. A mouse can be kept for weeks in the ‘cloister’ without any intervention from the observer. The behavior of the mouse was measured by three kinds of variables: position, movement and duration of stay. The number of passages through each sector (Cl) and the duration of stay in each sector (CZ)were counted and recorded automatically with an electronic measuring device using the principle of capacity detection (Fig. 2). Visual stimuli and/ or those of other modalities were applied at specified sectors. The visual stimulus mainly used was a presentation of another mouse to the one in the cloister through its transparent wall. The amount of movement, arrest of movement by stimuli, mean and maximum velocity were calculated from the measurements and used respectively as indices of

197

S T U D I E S O N METHAMPHETAMINE I N T O X I C A T I O N

Fig. 2. Schematic diagram of the cloister. FW = sector of food and water; Sm = sector of the olfactory stimulus; Sp = sector of the acoustic stimulus; Mo = sector of visual stimulus; L = light.

motor activity, responsiveness and agility of the mouse. Behavior trait could thus be formulated in terms of these measurements. The decrease in activity of the methamphetamine-intoxicated mouse was also demonstrated by this method. The intoxicated mouse ran with slower speed and in a

u 2000 2500

Fig. 3. Motor activity of mouse. On the abscissa, motor activity in the cloister is plotted by the count of movement (XI) for an hour; and on the ordinate, its frequency is indicated. Solid line = dd-strain mouse; broken line = methamphetamine-intoxicated mouse. References p . 2061207

198

H. U T E N A

narrower range of variation of velocity than normal controls, in other words, its movement was dull, sluggish and monotonous (Figs. 3 and 4). When the amount of movement per hour (CI) and the length of stay per hour (C2) at each sector are plotted on 20 radial scales, figurative patterns of behavior can

dd

05

1.0 1.5 2.0 2.5 3 0 3.5 4.0 4.5 50 5.5 6 0 6.5 7 0 7 5 (C,/C,)

80

rnax. 1 h

Methamphetamine

05

10 15

2 0 2 5 30 3 5 4 D 4 5 5.0 5 5 60 6.5 7 0 7 5 80 (C,/C*)

rnax 1 h

Fig. 4. The maximum velocity of dd and methamphetamine-intoxicated mouse. Frequency distribution of the maximum velocity, (C1/Cz)ma,. The maximum velocity is obtained from the mean velocity, (CI/CZ),counted for an hour, 240 times over 10 days. The abscissa indicates the number of passages through the sector (one sector = 10 cm) per sec.

be drawn as shown in Fig. 5. This mode of expression was named ameboid expression, because of its similarity to the shape of the ameba. Fig. 6 presents various patterns of behavior of the normal mouse, which can be arranged on diagonal axes. Figures on axis B indicate the patterns of behavior in various degrees of activity from rest to random excitement, while those on axis A include an arrest of movement in front of stimulus (S) and an activity oriented to S. The former patterns might be called a ‘non-specific or protopathic’ type, the latter a ‘differential or epicritic’ type of activity (Figs. 5 and 6). In contrast to normal patterns, the repertory of behavior patterns of the methamphetamine-intoxicated mouse is remarkably poor, because it is virtually devoid of the ‘differential’ patterns of activity. This animal is only capable of such behavior as loitering or eating and sleeping, and cannot relate itself in the ordinary way to its mate. Although it showed an increased random activity when put into an unaccustomed runway, it soon fell into an inactive state and toward the stimulus mouse it

199

STUDIES ON METHAMPHETAMINE INTOXICATION

7

5

-

I

4

/

,

3

2 ‘(50 1

Fig. 5. Ameboid expression of behavior. Distribution of CI and CZas the pole coordinate in the cloister. The numbers on the pole coordinate are plotted linearly for CI, the amount of movement per hour at each sector, and logarithmically for CZ,the length of stay per hour at each sector. The sector number is indicated outside. The prqjection of ameboid figure means the response to stimuli.

o Amphetamine

dd

B

A

7 1oc

1c

1

%.

100

1000

zc1

Fig. 6. Relation between the patterns of the ameboid expression and movements. amph. phetamine-intoxicated mouse. dd = dd-strain mouse. ( ) sector number. References p . 2061207

=

metham-

200

H. U T E N A

could not show a sensitive reactiveness such as seen in the normal mouse (Utena and Hirao, 1964; Hirao and Utena, 1965). The term 'autistic' seems suitable for describing this type of behavior, since the withdrawal tendency, monotonous sluggishness and disorganized excitement observed i n the intoxicated mouse, are all commonly found in the autistic behavior of schizophrenic patients. It is surprising that characteristics of behavioral aberration can be found in common in such widely differing species as humans and mice. On the other hand, individual differences i n susceptibility to the aberration were fairly great. In the intoxicated mice, typical motor depression could be observed in only two-thirds of the individuals, when measured by the revolving wheel (32 out of 50 experiments). However, mice without any sign of motor depression showed some traits of responsive abnormality. Experiments on cats Cats were also treated with a single or a long-term administration of methamphetamine HCl in a daily dosc of 3 mg/kg. The dosage in the chronic experiment was determined empirically for each species so as to obtain a sufficient effect and to avoid physical exhaustion. Behavioral changes in cats were rated by the scoring method of Norton (1957), which was modified slightly for the present purpose. Thirty items of elementary Scores Sociability

Anti-soclabllity

Contentment

n

m

i

m

Exci tem ent

I Defensive hostility

i

m

A ggresscvc hostility

i r

.

-

15

N

mama

CP

MAY".

CP

CP

Fig. 7. Behavioral changes induced by methamphetamine and/or chlorpromazine. N - untreated; ma methamphetamine HCI 5 mg/kg s.c., observed for 1 h after the injection. ma CP == added chlorpromazine 3 mg/kg s.c., 30 min after methamphetamine HC1 5 mg/kg and observed for I h after the last injection. MA = long-term administration of methamphetamine HCI 3 mg/kg s.c., daily for 30-50 days, observed for 1 h, 48 h after the last injection. MA I-CP = long-term administration of methamphetamine HCI 3 mg/kg S.C.daily for 30-50 days. Added chlorpromazine 3 mg/ kg s.c., 48 h after the last methamphetamine injection and observed for 1 h after the chlorproniazine injection. CP =: chlorpromazine 3 mg/kg s.c., observed for 1 h after the injection. ~

+

STUDIES O N METHAMPHETAMINE INTOXICATION

20 1

behavior, such as mewing, coming nearer, purring etc., were organized into several patterns, which were called anthropomorphically: sociability, anti-sociability, contentment, excitement, defensive hostility and aggressive hostility. Fig. 7 summarizes the changes in behavior induced by the drug. The changes in behavior produced by a single dose of methamphetamine were characterized by increased scores in excitement and defensive hostility. On the contrary, the main features of behavioral changes produced by a long-term administration of methamphetamine were an increase in anti-sociability as well as a decrease in excitement and hostility. Thus, an autistic behavior was also recognized in cats as in mice and humans. As Fig. 7 also indicates, these methamphetamine-induced changes in behavior were alleviated markedly by an additional administration of chlorpromazine (Funatogawa, 1964). NEUROCHEMICAL CORRELATES O F BEHAVIORAL CHANGES I N

M ET H A M P H E T A M I N E - I N T O X I C A T E D A N I M A I. S

In view of the long-lasting but reversible behavioral aberration induced by the methamphetamine-intoxication, it was assumed that the aberration might be due to some kind of biochemical changes i n the brain. Brain constituenfs of animals in the vesting state The contents of labile constituents in the brain of normal and methamphetamineintoxicated mice measured so far are listed in Table 11. The animals in a resting state were dropped in toto into liquid oxygen, and chemical determinations were made in the extracts from the frozen brain. As shown in the Table, it was found that brain ammonia in the intoxicated mice decreased, while acetylcholine increased significantly. These results are similar to those found in the brain of animals in a sedated T A B L E 11 L A B I L E C O N S T I T U E N T S I N T H E B R A I N OF MICE

ATP ADP AMP CrP Inorganic P Lactic acid Ammonia, NH3 Glutamine Acetylcholine

* 0.05 .;:

P

:,

PMlg / W g

PMlg /Wg P M/g PMlg pM/g N / g nipM/g

2.83 0.24 (7) 0.75 0.03 (7) 0.32 0.07 (7) 3.51 0.46 (12) 4.69 & 0.79 (12) 1.90 0.24 (10) 0.25 & 0.03 (18) 5.07 & 0.4 (6) 9.2 0.7 (9)

+

0.1, significant difference.

** 0.001 < P < 0.01, significant difference. References p . 2061207

2.47 k 0.41 (14)* 0.73 & 0.09 (14) 0.40 i 0.09 (14)* 3.36 4. 0.45 (13) 4.71 5 0.46 (13) 1.90 & 0.22 (8) 0.15 f 0.04 (9)** 5.54 & 0.41 (5) 11.0 & 0.8 (lo)**

202

H. U T E N A

state. Slight decrease in ATP and creatine phosphate was also noticed (Shimizu, 1961 ; Shimizu et al., 1962; Osuga et al., 1964). Significant increase in chloride space in the brain was reported by Hirano and Shimizu (1962). The functional significance of the changed levels of brain constituents is difficult to determine, for these levels indicate only a dynamic balance between chemical processes. In order to obtain more information, these levels were made to change by stimulation and were compared with concomitant changes in behavior. Chemical response in the bruin to stimuli The changes in brain ammonia in mice were estimated after 4 kinds of stimulative procedures, namely, methamphetamine injection, electroshock applied to the feet, transfer from a home cage to a revolving wheel and successive tosses for 20 sec. I n this experiment the revolving wheel was used as a kind of stimulative living condition. As shown in Fig. 8, responsive increase in brain ammonia of the intoxicated mice occurred in the same degree and indiscriminately to all the stimuli, whereas that of normal mice occurred in a differential manner depending on the stimulus (Shimizu et al., 1962).

0.2

-

j

Home cage

j

b----k

-I

j

ES

4

b

Toss

t

----

Wheel

+

----+

t - - - - -- Normal c o n t r o l inice

Fig. 8. Changes in ammonia level in brain produced by stimulative procedures. Stimulative procedures: (1) Resting state in home cage; (2) methamphetamine HCI 2.8 mg/kg s.c., 60 min after injection; ( 3 ) electroshock applied to the feet, 40V, 5 sec; (4) tosses, 30 times/20 sec, 15 min afterwards; (5) transfer from home cage to revolving wheel, 60 min afterwards.

The time-course of changes in levels of brain ammonia, ATP and creatine phosphate was measured under mild stimulation in a revolving wheel. When a mouse was kept in a revolving wheel, the levels of brain constituents of the intoxicated mouse changed in a plateau-shaped course with the peak value much retarded compared with that of the normal one (Osuga et al., 1964) (Fig. 9). The loss of differential response and the prolonged time-course of change are distinctive features of the chemical processes in the brain of the methamphetamineintoxicated mice. They seem to substantiate the similar behavioral characteristics i n these animals, i.e. the non-differential type of response and the tendency to retention

S T U D I E S O N METHAMPHETAMINE INTOXICATION

b c a q e revolving+% w ---I eel ---. OiOrnln

6Ornin

203

--:i--7 days

‘4da~

Fig. 9. Time-course of changes in brain ammonia, ATP, and creatine phosphate induced by transfer from home cage to revolving wheel.

of behavior patterns. However, whether or not there is a causal relationship between the chemical and behavioral processes cannot be answered solely from such parallelism of phenomena. In view of the finding that an elevated level of ammonia in the brain is usually accompanied by neuronal activity, the plateau-shaped course of ammonia seems to suggest a persistence of an activated state of brain function. This interpretation is not easily compatible with the concurrent changes in ATP and creatine phosphate. Further studies are needed on phosphate turnover and on enzymatic activity relevant to the chemical processes. R E D I S T R I B U T I O N O F B R A I N S E R O T O N I N I N R E L A T I O N TO BEHAVIOR O F CATS

Functional implications of chemical processes have to be considered in terms of neurophysiology. Average amounts of substances in the whole brain, such as those described above, are not open to any interpretation as to detailed functions. It is well documented that some constituents of functional importance are peculiar in their topographical distribution in the brain. Serotonin is one of these substances. Funatogawa (1964) attempted to study a correlation of the changes in serotonin levels in different structures of the cat brain with changes in behavior. Cats were guillotined without anesthesia, and the following parts of the brain were sectioned out in the cold : cerebral cortex, hypothalamus, thalamus, caudate nucleus, hippocampus, midbrain reticular formation and cerebellum. Serotonin was extracted from the homogenized tissues into butanol, and determined fluorometrically by the method of Udenfriend (1962), using the Hitachi Spectrofluorophotometer. Topographical distribution of serotonin in the brain of unanesthetized cats was nearly the same as that in anesthetized cats, as reported by Bogdanski et al. (1957). The References p . 2061207

204

H. UTENA

highest value was found in the amygdala, the next in the reticular formation and the hypothalamus, and the lowest in the cerebellum. After a single administration of methamphetamine HCI (5 mg/kg s.c.) serotonin decreased in the cerebral cortex and the hypothalamus, and increased in the amygdala, the reticular formation and the cerebellum. With a long-term administration of methamphetamine HCI (3 mg/kg s.c., daily for 30 to 50 days), serotonin increased in most parts, but decreased in the caudate nucleus. Additional administration of chlorpromazine HCl (3 mg/kg s.c.) had a normalizing effect on serotonin levels, which had been changed by methamphetamine, with the exception that in the amygdala the increased level of serotonin remained unchanged (Fig. 10).

uyLm* pg!lh*&, 1

Cerebral cortex

Hippocarnpus

Q

2 1

1

HYPcthalamus

Amygdala

2

I

2

I

1

1

Thal miu 5

Reticular formation

0

Control

’

Methamphetamine Longterrn

a

Chlarpromazine (CP) MA+CP

dFA’ &LIo n g t e r m

MAtCP

Fig. 10. Effects of methamphetamine and/or chlorpromazine on topographical distribution of brain serotonin in cats. See Fig. 7.

When the patterns of the distribution of brain serotonin induced by the drugs were compared with the patterns of behavioral changes in the respective conditions, some striking similarities were observed. The levels of serotonin in the cerebral cortex and the hypothalamus were conversely changed between a single and a long-term administration, and the concomitant changes in the patterns of behavior were also opposite in the two conditions. It seems to be of special importance that the methamphetamine-induced changes in serotonin distribution, which can be normalized partially by chlorpromazinereappeared after the chlorpromazine effect had disappeared. This finding substan, tiates a persistence of some mechanism which works by sustaining the abnormal

STUDIES O N METHAMPHETAMINE INTOXICATION

205

state in the brain. In this connection the chlorpromazine-resistant amygdala may play some important role in producing a long-lasting change in brain function (Table 111). T A B L E 111 EFFECTS OF C H L O R P R O M A Z I N E ON B R A I N S E R O T O N I N IN M E T H A M P H E T A M I N E - I N T O X I C A T E D CATS

Untreated

Cerebral cortex Hypothalamus Thalamus Caudate nucleus Hippocampus Amygdala Reticular formation Cerebellar cortex

0.29 f 0.04 (517 0.91 & 0.09 (5) 0.74 & 0.09 ( 5 ) 0.74 0.09 ( 5 ) 0.12 & 0.03 ( 5 ) 1.16 f 0.09 ( 5 ) 0.83 & 0.13 ( 5 ) 0.13 0.02 ( 5 )

+

(Pdd

Long-term MAa

Long-term M A b ( 1 h)-CP

Long-term MAC (24 h)-CP

0.36 0.03 (4)* 1.28 & 0.04 (4)* 1.16 f 0.09 (4)* 0.57 f 0.09 (4)* 0.14 rt 0.03 (4) 1.52 & 0.17 (4)* 1.52 f 0.1 7 (4)' 0.28 f 0.10 (4)*

0.42 & 0.09 {3) 1.26 f 0.35 (3) 0.78 & 0.22 (3) 0.96 & 0.13 (3)* 0.22 f 0.10 (31 1.57 f 0.30 (3)* 0.67 mean (2) 0.23 0.06 (3)*

0.47 & 0.14 (4)* 2.06 f 0.39 (4)* 1.03 rt 0.19 (4)* 1.04 rt 0.15 (4)* 0.41 & 0.09 (4)* 2.74 rt 0.12 (4)* 1.90 & 0.24 (4)* 0.47 f 0.20 (4>*

aLong-term MA: long-term administration of methamphetamine HCI, s.c., 3 mp/kg daily for 30-50 days. Killed 48 h after the last injection. bLong-term MA(1h)-CP: long term administration of methamphetamine HCI, s.c., 3 mg/kg daily for 3@SO days. Additional administration of chlorpromazine 3 mg/kg, 48 h after the last methamphetamine injection. Killed 1 h after the chlorpromazine injection. Long-term MA(24h)-CP: long-term administration of methamphetamine HCI, s.c., 3 mg/kg daily for 30-50 days. Additional administration of chlorpromazine 3 mg/kg, 48 h after the last methamphetamine injection. Killed 24 h after the chlorpromazine injection. t Mean & SD. ( ) Number of expts. * Significant (P = 0.05).

According to the work of McLean and McCartney (1961) the treatment of rats with amphetamine lowered brain noradrenaline and slightly elevated brain serotonin. Tn methamphetamine-intoxicated cats, noradrenaline in the brain was assumed to have fallen. Redistribution of brain noradrenaline with concomitant changes in behavior is now under investigation in the author's laboratory. Neurophysiological studies The neurophysiological studies on methamphetamine-intoxicated animals are still insufficient. Ishikawa (1963) examined the EEG patterns of rabbits chronically intoxicated by methamphetamine. The changes in an EEG with scalp electrodes were characterized by a tendency to persistence of arousal pattern and a diminished response to auditory stimulus. The changes lasted for 3-weeks after the administration was discontinued. Fujita'and Sasaki (1965) made electrophysiological studies in deep brain structures of intoxicated cats, and demonstrated that spike activity was induced in the amygdala by methamphetamine stimulation after 3 weeks of daily administration of the drug. This finding suggests an alteration in function of this structure. References p . 206/207

206

H. U T E N A

Histopathological studies As to the histopathological examinations, Yokoi and Akiyama (1958) reported that no definite change was found in the brain of methamphetamine-intoxicated guinea-pigs, except small hemorrhages and minor changes of non-specific character i n nerve cells. Numabe (1965) also confirmed that no change was found in nerve and glial cells in the brain of methamphetamine-intoxicated cats. The negative findings in these works again suggest the functional nature of this condition which may be sustained by some kind of biochemical disturbances. SUMMARY

Studies on chronic methamphetamine intoxication are presented. Schizophrenia-like features, residual states of long duration and a tendency to relapse were peculiar to this type of intoxication psychosis. Behavioral aberrations were produced by a longterm administration of methamphetamine in various kinds of animals, such as guinea-pigs, mice, rats and cats. Behavioral traits common to all the intoxicated animals were a reduced motor activity, a loss of differential responsiveness, and a tendency to retention of behavior patterns. The analysis and formulation of behavior i n animals were made by the use of several measuring methods, including the ‘cloister’ method. Brain constituents of mice were determined in in vivo conditions. Levels ofammonia. acetylcholine, ATP, and creatine phosphate in brain of the intoxicated mice were found to be different from those of normal controls. Behavioral and chemical aspects were both correlated with each other with special regard to responsive change and its time-course. Administration of methamphetamine to cats induced a rearrangement of distribution of serotonin in brain, the functional significance of which has been discussed in relation to the behavioral changes. REFERENCES ARIYASU, T., (1964); A follow-up study on the prolonged cases of addiction due to p-phenylisopropylmethylamine. Collected Papers in Commemoration of Honorary Professor Kora. Tokyo Jikei-kai Medical School (p. 343-368). BOGDANSKI, D. F., WEISSBACH, H., AND UDENFRIEND, S., (1957); The distribution of serotonin, 5-hydroxytryptophan decarboxylase and monoamine oxidase in brain. J . Neurochem., 1, 272-278. CONNELL, P. H., (I 9 5 8 ) ; Amphetamine Psychosis. London, The Institute of Psychiatry. FUJITA, H., AND SASAKI, H., (1965); Electrophysiological studies on methamphetamine-intoxicated cats. To be published. FUNATOGAWA, S., (1965); Methamphetamine-induced changes in behavior of caLs and in topographical distribution of brain serotonin. Psychiat. Neurol. jap., 66, 743-754. GOTO,T.. (1960’; Clinical pictures shown by long hospitalized cases of chronic methamphetamine psychosis; a comparative study with schizophrenia. Psychiat. Neurol. jup., 62, 163-176. HIRANO, S., A N D SHIMIZU, T., (1962); EIectrolyte distribution in brain tissue of convulsive ep and chronic methamphetamine-intoxicated mouse. Advanc. neurol. Sci., 6, 651-653. HIRAO, T., AND UTENA, H., (1965); Analysis of behavioral space. Psychiat. Neurol. jup., in the press. ISHIKAWA, M., (1963); On addiction and tolerance; electroencephalographic studies in animals with special regard to effects of long-term administration of morphine and methamphetamine. Nippon Yakurigaku ZasJhi (Jap. J. Pharmacol.), 59, 187-205.

STUDIES ON METHAMPHETAMINE INTOXICATION

207

MCLEAN,J. R., AND MCCARTNEY, M., (1961); Effect of D-amphetamine on rat brain noradrenaline and serotonin. Proc. Soc. exp. Biol. ( N . Y . ) ,107,77-79. MORIGUCHI, N.,(1963); Avoidance learning under the condition of abulia, induced by chronic administration of methamphetamine hydrochloride. Ann. Animal Psychol., 13, 49-55. NORTON,S., (1957); Behavioral patterns as a technique for studying psychotropic drugs. Psychotropic Drugs. s. Garattini and V. Ghetti, Editors. Amsterdam, Elsevier (p. 73). NUMABE, T., (196.5); Histopathological studies on methamphetamine-intoxicated cats. To be published. T., SHIMIZU, T., AND UTENA,H., (1964); Changes in creatine phosphate and adenine nucleoOSUGA, tides in brain of methamphetamine-intoxicated mice. Neurochemistry, 3, supplement, 73-76. SHIMIZU,T., (1961); Ammonia content in the brain and the motor depression in mice. Pswhiut. Neurol. jap., 63,941-951. SHIMIZU,T., YUASA,S., AND FUNATOGAWA, S., (1962); Behavioral characteristics of mice with reduced activity and changes in level of brain constituents to various stimuli. Advunc. neurol. Sci., 6, 646-650. TATETSU, S., GOTO,A,, AND FUJIWARA, T., (1956); The Awakening Drug Intoxication. Tokyo, Igakushoin. S., (1962); Fluorescence Assay in Biology and Medicine. New York and London, UDENFRIEND, Academic Press. UTENA,H., (1961); A special type of model psychosis; a chronic methamphetamine intoxication in man and animal. Bruin Nerve, 13, 687-692. UTENA, H., AND EZOE.T., (1951); Studies on the carbohydrate metabolism in brain tissues of schizophrenic patients. Psychiat. Neurol. jap., 52, 204228. UTENA,H., EZOE,T., AND KATO,N., (1955); Biochemical studies on addiction due to P-phenyIisopropylmethylamine. (1) Tissue distribution and secretion of the amine. (2) Effect on glucose metabolism in brain tissue. Psychiat. Nercrol. jap., 57, 1 15-1 30. UTENA, H., EZOE,T., KATO,N., AND HADA,H., (1959;; Effects of chronic administration of methamphetamine in enzymic patterns in brain tissue. J. Neurochem., 4 , 161-169. UTENA,H., A N D HIRAO,T., (1964); Formulation of normal and aberrant behavior chains. Brain Nerve, 16,31-39. UTENA, H.,AND TAKANO, S., (1960); Reduction of spontaneous activity of mice induced by drugs. Folia psychiat. neurol. jap., Supplement 6, 38-47. YAGI,M.,(1963); Factors influencing the general activity in rats. (2) Effect of methamphetamine. Ann. Animal Psychol., 13,3747. YOKOI,S., AND AKIYAMA, Y., (1958); Histopathological studies on intoxication due to methamphetamine. Kitakanto Igaku, 8,296-303.

208

Fundamental and Clinical Studies on the Neural Mechanism of Sleep T E R U O OKUMA

AND

H A R U O AKIMOTO

Department of Psychiatry, Faculty of Medicine, University of Tokyo andLahoratory of Neurophysiology, Neuropsychiatric Research Institute, Tokyo (Japan)

The study of the neural mechanism of natural sleep has a long history, but the recent revival of the study o f this problem is thought to be stimulated by the observation o f Dement and Kleitman (1957) and Dement (1958) that the low voltage fast neocortical pattern which had been considered to be characteristic o f the waking state, could be recorded also during a fairly deep stage of sleep called ‘activated sleep’. The importance o f this discovery lies not only in the paradoxical dissociation between the behavioral sleep with dreaming and the electrographic arousal pattern, but also i n its contribution to the electrographic identification of the sleep cycle. That is, the activated sleep stage was found to be a convenient signal which marked the end point o f each sleep cycle. Since the early study on the experimental induction o f sleep by repetitive stimulation of the non-specific thalamic nuclei on dogs (Akirnoto et al., 1956), the authors and their collaborators have investigated various problems on natural sleep by using both fundamental and clinical approaches. These studies will be described in outline under several headings in the present paper.

(I) The spontaneous electric activity of the brain during sleep By using adult cats with chronically implanted cortical and subcortical electrodes, the electric activity o f various structures of the brain was recorded together with the eye movements, EMG of the posterior neck muscles and ECG (Okuma et al., 1961, 1962, 1963). Physiological sleep of the cat was divided into 4 stages: A (arousal) stage with low voltage fast neocortical activity, S-1 stage with a 6 to 14 c/s spindle burst in the neocortical electrogram, S-2 stage with spindle and high voltage slow activity in the neocorticogram, and S-A stage with electrographic features similar to those of the arousal stage and accompanied by abolition of neck muscle tone-and occurrence of rapid eye movements (REM). It was also observed that there was some fluctuation in the activity level o f the brain even during the S. A stage. That is, during the typical S-A stage with low voltage fast neocortical and rhythmic hippocampal activity, disappearance o f neck muscle tone and occurrence of rapid eye movements, periods accompanied by 10 to 14 c/s rhythmic

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activity and sometimes 6 to 10 cjs spindle bursts in the neocorticogram were inserted transiently. In such periods, the hippocampal rhythmic activity decreased its rhythmicity, and the incidence of the rapid eye movements became lower but the state of the abolition of the muscle tone persisted. The period of the S-A stage with the rhythmic neocortical activity was called the S-A-2 stage, and the typical S-A stage was called the S A-1 stage. The typical S-A-I stage was also divided into the period with rapid eye movement and that without eye movement. It seems to be important to pay attention to these three different periods during the S-A stage (S-A-1 with REM, S-A-1 without REM and S-A-2), because the electric activity of the brain as well as the peripheral somatic and autonomic activities might show considerable differences in these three stages as will be mentioned later (Okuma et al., 1961; Okuma, 1962, 1963; Okuma and Fujimori, 1963). The low voltage fast neocortical patterns during arousal and the S-A stage were very similar, but when analyzed by using the automatic frequency analyzer, the neocortical activity during the S-A stage contained more &activity compared with that of the arousal stage when the REMs were appearing. However, the electrogram in the period of the S-A stage without REMs showed no significant difference from that of the arousal stage in the amount of the integrated value of each frequency band (Fig. la). The hippocampal rhythmic activity was of higher frequency during the S-A stage than in the arousal stage. The frequency of the activity, which was 3 to 5 cis SMCx

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Fig. 1. Automatic frequency analysis of the neocortical and hippocampal electrograms during different stages of sleep in the cat. The abscissa shows 10 frequency bands of the analyzer and the ordinate indicates an arbitrary unit showing integrated activity of each frequency band. The means of the values of ten 10 second epoques belonging to the same sleep stage are shown. The S-A (activated sleep) stage was divjded into two periods. EM(-), period without rapid eye movements; E M ( + ) , period in which rapid eye movements occurred. In (a) (the sensorimotor cortex) the activity of the 0-band was higher during the S-A-EM(-I-) period than in the arousal stage whereas the &activity was almost the same between the S-A-EM(-) and arousal stages. In (b) the shift of the peak frequency of the hippocampal rhythmic activity to the higher side was evident during the S-A stage. Ruf(>rencrs p . 2281229

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during the waking stage, increased definitely and became 4 to 7 c/s during the S-A stage (Fig. Ib). The frequency became particularly high during the period of the rapid eye movement as shown in Fig. 2 (Okuma, 1962; Okuma and Fujimori, 1963). It is well known that the electrocortical pattern during sleep shows considerable difference between the cat and man. The drowsy pattern which consisted of low voltage flat, mixed with low voltage 0 and fast, activity (stage of suppression) and which lasted for at least a few minutes at the onset of human sleep could scarcely be observed in the cat. The hump stage and the &stage without spindle burst were also almost lacking in the feline sleep electrogram. In order to clarify these differences from the standpoint of the phylogenetic development of the brain, the electric activity of the cerebral cortex and other subcortical structures was recorded together with eye movements, EMG of the neck muscle and other polygraphic items during natural sleep in 4 crab-eating monkeys (Macaca irus), and compared with those of the cat and man (Okuma and Sasaki, 1964). The depth of sleep of the monkey was divided into the following 6 stages according to the characteristics of the electrocortical activity (Fig. 3); (1) A-1 stage (arousal and alert) with low voltage fast neocortical activity, (2) A-2 stage (relaxed arousal) with 10 to I3 c/s synchronized a-like activity in the temporo-parieto-occipital regions, (3) S-1 stage (drowsy) with a short period of a flat pattern followed by a stage of irregular 4-6 c/s activity, (4) S-2 stage (light sleep) with vertex sharp waves (hump) followed by spindle bursts of around 13 and 18 c/s, (5) S-3 stage (moderately deep sleep) with spindle burst of around 14 c/s and 1-3 c/s high voltage slow activity, and (6) S-A stage (activated sleep) with low voltage fast neocortical activity accompanied by rhythmic hippocampal activity, rapid eye movements and disappearance of neck muscle tone. During the S-A stage, sustained bursts of rhythmic fast activity of around 20 c/s

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and 50 pV appeared intermittently in the temporo-parieto-occipital cortices (Fig. 3 S-A). The fast activity was not so marked in the other stages of sleep, and it seemed to be possible to identify the S-A stage by the occurrence of the rhythmic fast activity. The hippocampal rhythmic activity in the S-A stage was far less prominent in the monkey compared with that of the cat. The moderately deep sleep in the monkey tended to appear in the evening and in the early morning, that is, the monkey has approximately two sleep phases during R<~.jrrmccs p. 2281229

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Fig. 4. The sleep cycle and phase patterns of a cat (a) and a monkey (b). The continuous plotting of the electrographic pattern for 24 h showing stages of sleep and wakefulness is indicated on the ordinates. The S-A (activated sleep) stages are shown by black columns. (a) Cat: during 24 h 7 sleep phases which lasted for 2 to 3 h and consisted of 2 to 6 sleep cycles were observed. In this diagram the top and the second lines are continuous, each representing 12 h. (b) Monkeys sleep chiefly during the night. Each line represents 24 h. The first and the second lines are continuous sleep diagrams for two days in a monkey. The third and the fourth lines are sleep diagrams of another monkey on two different nights. Two sleep phases could be discerned during a night.

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the night and is mostly awake during the daytime (Fig. 4b). The depth of sleep was fairly shallow at midnight. Each sleep phase usually consisted of about 3 to 4 sleep cycles. This sleep phase and cycle pattern of the monkey lies between the polyphasic feline and monophasic human sleep pattern. The electrocortical sleep pattern also showed intermediate characteristics. The appearance in the monkey of a suppressed flat pattern in the drowsy state, vertex sharp waves in S-2, and high voltage &pattern in the S-3, stages showed a close resemblance to the pattern of human sleep EEG, whereas the occurrence of a low voltage fast neocortical pattern during the S-A stage seems to be comparable to that of the S-A stage of the cat. The polygraphic study on the human nocturnal sleep had been made by simultaneously recording EEG, ECG, respiration rhythm, eye movements, GSR, finger plethysmogram, body movements and skin temperature on 72 healthy adults (age 18-31; 69 males and 3 females) in 90 undisturbed nights of sleep and 19 nights with various kinds of stimulation (Koga, 1960, 1963). The nocturnal sleep of the human subject was divided into 4 stages: the hypnagogic stage, moderately deep sleep stage, deep sleep stage and paradoxical phase (S-A stage). The EEG pattern during the S-A stage in the human subject consisted of amorphous low voltage (below 50 p V ) activity of 6-, 8-, a-, and P-bands. Frequency analysis made with an automatic frequency analyzer showed that the slower component was more pronounced during the S-A stage than during the hypnagogic stage. In order to determine the depth of sleep in each stage, the reaction time was measured as the time from the beginning of a continuous 1000 cjs pure-tone stimulation to the response of the subject (a voluntary flexion of the right thumb which was recorded by a high sensitivity vibration transducer). The reaction time became longer as sleep deepened, and in the moderately deep, deep and S-A stages it was almost identical. The EEG pattern in the hypnagogic and S-A stages was similar but the reaction time was found to be very much shorter in the former than in the latter, The reaction time tended to become longer, even in the same EEG stage of sleep, in the second or third sleep cycle in the night compared with those of the first and last cycles of sleep. The change in galvanic skin response (GSR) was also investigated in detail during human nocturnal sleep (Koga, 1960). In the waking state, the frequency and amplitude of spontaneous and evoked GSR were more predominant in the palm than in the back of the hand and the forearm. During sleep, however, the relationship reversed and the GSR in the back of the arm tended to become predominant. The incidence of spontaneous GSR during sleep increased as the depth of sleep advanced, and an almost parallel relationship was found between the incidence of GSR and depth of sleep except for that during the activated sleep, in which the incidence of spontaneous GSR decreased markedly. It was also found that GSR evoked by repetitive click stimulation (every 15 sec) showed marked adaptation in the waking state, whereas it showed a tendency towards de-adaptation during sleep. The GSR in the palm was considered to be due to psychic perspiration and controlled by the cerebral cortex, whereas the GSR in the back of the hand was due to thermal perspiration and conRiyewnces p . 2281229

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Fig. 5. (a) Typical EEG pattern of the 6 sleep stages of children. Calibrations, I sec and 50 p V . (b) Diagrammatic representation of sleep cycle pattern of children. The abscissa shows the chronological time. The different patterns of columns represent the stage of sleep shown in (a). To the left of the diagrams are shown the age of the subject (1 : 5 1 year and 5 months), Note the consistent appearance of the diffuse rhythmic 0-stages. 7

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trolled by subcortical centers. Thus the predominance of the former in the waking state was explained by the predominance of the cortical activity during wakefulness and the enhancement of the latter during sleep by the release of the subcortical activity. The sleep EEG pattern of children was found to have several characteristics different from those of the adult (Takano et a/., 1963; Uchinuma et a/., 1963) (Fig. 5). All-night polygraphic recording of EEG, ECG, respiration and body and eye movements were carried out on 30 healthy children whose ages ranged from two days to 15 years. The sleep of children was classified electrographically into 6 stages: awake, drowsy, spindle, 6, diffuse rhythmic 0 and slow rhythmic wave (rapid eye movement (REM) ) stages. Two types of rhythmic waves were observed during the nocturnal sleep of children. They were named ( I ) diffuse rhythmic 6-waves and (2) slow rhythmic waves. The diffuse rhythmic 0-waves (Fig. 6a) were diffuse in distribution, approximately 6 cis, and of 40 to 150 pV appearing predominantly in the central region. They were continuous or paroxysmal and often mixed with 12 to 14 c/s spindles. This pattern appeared more marked in the early portion of nocturnal sleep and gradually decreased towards the morning. The stage of diffuse rhythmic waves continued for 15 to 50 min, and during this stage the respiration was regular, the pulse rates low and no REM seen. This pattern seemed to form one of the sleep stages of young children from 1 year to 6-year-old. Trains of slow rhythmic waves were found in the records of REM period (Fig. 6b). They appeared predominantly in the REM period in the later portion of nocturnal sleep, and typical slow rhythmic waves appeared in the last part of REM period when REM rarely occurred. The slow rhythmic waves were more strictly localized in the central region, being 3-5 cis, 30 to 150 pV and resembling the steady slow activities of drowsiness (Gibbs and Gibbs, 1950). Newborn children were found to show a rapid eye movement (REM) period at the beginning of sleep, though the REM period usually occurred only after passing through the spindle and slow activity stages in normal adults. In young children, the REM period sometimes occurred following a prolonged wakefulness in the course of nocturnal sleep. The younger children showed more regular and frequent REM periods and a higher percentage of REM periods in their total sleep time than was observed in adults.

(2) Changes of evoked potentials during sleep in the cat I n order to analyze the functional state of the brain during sleep, various kinds of

evoked potential in the cerebral cortex, thalamus and brain stem structures induced by stimulation of the peripheral and central nervous structures (Okuma ef al., 1961, 1963, 1964a-d; Okuma, 1962, 1963; Okuma and Fujimori, 1963) were recorded in different stages of physiological sleep. The amplitude changes of components of the evoked potentials with different latencies were measured and analyzed in relation to the background electrographic pattern and other polygraphic signs. Rcfcrrnrcs p . 2281229

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Evoked potentials in the specific sensory systems induced by direct electrical stimulation of the brain, such as potential in the visual cortex evoked by single shock to the optic tract, had short latency positive components and following negative components. The early positive components decreased in amplitude during the S-1 and S-2 stages with slow background activity, and showed the amplitudes equal to or (a)

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higher than the arousal level during the S-A stage (Fig. 3.Almost identical changes in amplitude were observed in response to both weak and strong stimulations (Okuma et al., 1964a-d). The amplitude of the negative components, however, showed rather inconsistent responses during the S-2 stage, that is, reduction in one stimulus intensity and enhancement to others, whereas a consistent marked enhancement was observed during the S-A stage. The enhancement of the ekoved potential in the specific system during the S-A. stage appeared more marked when low freqency (around 6 c/s) repetitive stimulation

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of the optic tract at 5-sec intervals. The ordinate of each graph shows percentage of control (arousal) amplitude of each component of the evoked potential, and the abscissa shows stages of sleep. The circles (threshold intensity of stimulation) and dots (maximal stimulation) show mean values of each component and bars show standard deviations. Note the enhancement of all the components during the S-A stage. No significant difference was found between the threshold and maximal stimulation. See text for further explanation. References p . 2281229

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was used. The amplitude of the evoked potential during the S-A stage became particularly large coincident with the rapid eye movement. The evoked potentials in the non-specific thalamocortical system such as the recruiting response, however, were enhanced in the S-1 and S-2 stages and suppressed during the S-A stage. The alteration in the evoked potential induced by sensory stimulation was also investigated during sleep in the cat. The amplitude of early positive and negative components of the click response in the auditory cortex showed an increase in ampli-

Fig. 8. Comparison of the change of somatosensory and auditory evoked potentials during sleep in the cat. (a) Evoked potentials in the sensorimotor cortex induced by electrical stimulation of the skin of the foreleg of the cat. The upper trace of each record shows original wave form and the lower one addition of 10 successive responses by using an analog type of average response computer (ARC). Stages of sleep are shown on the left. (b) Click response in the auditory cortex. Ten responses were added by means of the same ARC. Note the enhancement of the early positive and negative components during the S-A stage in the former (a) and supprcssion in the latter (b).

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tude during the S-1 and S-2 stages and marked reduction during the S-A stage. The evoked potential in the sensorimotor cortex induced by electrical stimulation of the skin of the foreleg showed amplitude alteration in the opposite direction, that is, decrease in the S-1 and S-2 stages and enhancement during the S-A stage (Fig. 8). The evoked potential in the mesencephalic reticular formation to electrical stimulation of the skin had an initial positive component with a peak latency of 25 msec followed by two negative components with latencies of about 40 and 80 msec. The amplitudes of the initial positive and the following negative components slightly decreased during the S-1 and S-2 stages and rose above the value of the arousal level during the S-A stage (Okuma et al., 1961, 1963). The difference in the change in the evoked potentials between the auditory and somatosensory systems may be mainly due to the difference in the mode of stimulation and electrical stimulation of the skin would induce a more synchronized afferent volley than click stimulation. The presence of input controlling mechanisms during sleep in the auditory and visual systems (change of the tone of the middle ear muscle in the former and of the size of pupils in the latter) would also explain, at least in part, the suppression of evoked potentials during S-A stage. From the results mentioned above, it seems pertinent to suppose that during the S-A stage of sleep, not only the spontaneous electrographic activity but also the excitability o f the cerebral cortex to the specific afferent stimuli are on the same level or higher than those in the arousal stage. As to a possible explanation o f the activated electrographic pattern and enhancement of the specific evoked potential during the S-A stage, it is thought that an overactivation of the ascending reticular activating system was induced by a release from the ascending inhibitory mechanism in the caudal brain stem which was suppressed during the S-A stage. The loss of postural muscle tone and other peripheral manifestations of sleep are also believed to be due to suppression of the regulating centers located in the caudal brain stem which maintained tonic activity of effectors. Recently, similar studies have been made on human subjects. The changes in evoked response induced by both click and electric nerve stimulation were recorded by scalp electrodes and average response computers (Nakagawa, 1964; Okuma et al., 1964b). The responses with longer latency and of secondary or diffuse in nature were markedly suppressed during the S-A stage.

( 3 ) Sleep phase and cycle pattern in difeerent species

As sleep is one of the cyclic phenomena of the living organism, the study of the pattern of sleep cycle and its modification by different physical and pharmacological procedures seems to be important for the elucidation of the neural mechanism of sleep. In the study of the sleep cycle pattern of the cat, monkey and man, two kinds of sleep rhythm, fast and slow, were observed. The faster one was the sleep cycle which had been defined as a period between the two successive activated sleep stages. The slower one may be called the sleep phase which is an assembly of several sleep cycles. References p . 2281229

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As mentioned before, the sleep phase recurs several times a day in the cat (polyphasic type of sleep), about twice a day in the monkey and once in the human adult (monophasic type) (Okuma ct al., 1963, 1964b,d) (Fig. 4). The sleep cycle pattern of the cat was found to be profoundly modified by repeated arousal stimulation (Okuma et al., 1964a). When a peiiod of S-A stage was interrupted by relatively weak arousal stimulation, the next S-A period recurred much sooner than expected, and a number of brief sleep cycles could be established successively. The pattern of the sleep phase of the cat, on the other hand, was not influenced significantly by repeated arousal stimulations, though the sleep cycle pattern in each sleep phase might be modified considerably. A similar principle was also applicable to the modifiability of the sleep pattern of the human subject, but the sleep cycle pattern of man during nocturnal sleep tended to be more stable and less modifiable than that of the cat. When the S-A stage of a human subject was interrupted by a relatively weak arousal stimulation, the EEG pattern showed a direct return from arousal or drowsy pattern to the S-A pattern without passing through spindle and slow activity stages. The electrocortical pattern of the cat in such instances, however, showed a gradual shift from arousal, through spindle and slow activity stages, to the S-A stage even though each stage was very brief. The differences between the cat and man in the neocortical electrographic pattern, and also in the response to the arousal stimulation during the S-A stage, may be explained by the difference in the development of the cerebral cortex in relation to the brain stem structures between the two species. The modifiability of the sleep cycle and sleep phase patterns by repeated arousal stimulation indicates that a sustained inhibitory process may exist in the background of natural sleep, particularly during the S-A stage. As to the effect of vaiious drugs on the sleep cycle pattern of the human subject, those of psychotropic drugs were interesting. That is, oral administration of 50 mg of chlorpromazine tended to increase the duration and total percentage of the S-A stage during one night’s sleep, whereas administration of 50 mg of imipramine, on the other hand, decreased the duration and total amount of the S-A stage and replaced it with the spindle stage accompanied by abundant body movements (Akimoto and Toyoda, 1963). Oral administration of 8 mg of perphenazine produced a similar change in the nocturnal sleep cycle pattern to that of chlorpromazine. Levomepromazine, on the other hand, showed an effect similar to that of imipramine, decreasing the period of the S-A and increasing the spindle stage. Levomepromazine, however, did not induce an increase in body movements, which was characteristic of imipramine. The effect of psychotropic drugs on the sleep cycle pattern was also observed in the animal experiments. The intramuscular injection of 5 to 10 mg/kg of imipramine in the cat increased spindle and slow activity in the neocorticogram but completely suppressed the occurrence of the S-A stage for at least several hours (Akimoto et al., 1963a,b). When imipramine was given daily for several days, its effect in suppressing the S-A stage diminished in a few days, and the S-A stage began to reappear even under imipramine administration, though the duration and total amount of the S-A

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stage was lower than in the control period (Fig. 9) (Okuma and Fujimori, 1964). The duration of each S-A stage as well as the total amount increased for a day or two immediately following the cessation o f the imipramine administration. The effect of chlorpromazine on the sleep cycle pattern of the cat varied according to the amount of the drug given to the animal. The effect of chronic administration o f methamphetamine, one of the waking amines, on the electric activity of the brain was also studied in cats together with observations of the behavior of the animal. It has already been established that the daily intramuscular administration of 3 mg/kg of methamphetamine usually produced the behavior changes defined as chronic methamphetamine intoxication within 30 to References p . 2281229

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60 days. As to the electric activity of the brain, spike activity began to appear in the amygdaloid nucleus and later in the hippocampus during 20 to 30 days of methamphetamine administration. The spikes diminished within several days following discontinuation of methamphetamine, and reappeared markedly by readministration of the drug (Fig. lo). In the neocortical electrogram, however, spikes were not evident, and a slight increase in the fast activity was observed, particularly during the S-A stage. l n the intoxicated cat, the total amount of sleep decreased, and the percentage of the S-A stage in the total time of sleep in a day also tended to be reduced, but the sleep cycle and phase pattern were not profoundly disorganized. It was assumed that the chronic administrationeof methamphetaminezdid not disturb the sleepImechanism itself but rather affected the function of the limbic structures (Okuma and Fujimori, 1964).

2

Fig. 10. Seizure discharges in the amygdala and hippocampus in chronically methamphetamineintoxicated cat ( 3 rng/kg for 90 days). Note the gradual disappearance of seizure discharges following discontinuation of the drug. (a) The 2nd day, (b) 10th day and (c) 25th day following the discontinuation of the drug.

( 4 ) Epileptic seizure discharge during sleep

It has been our common experience that epileptic seizures occur frequently during sleep, and tleep activation has been used in clinical electroencephalography to detect electrographic seizure discharges, particularly focal abnormalities, in some groups of epileptics. In animal experiments the change in experimentally induced focal seizure discharges in the neocortex and limbic structures has been studied during different stages of sleep in the cat, because the seizure discharge may be considered to be convenient identifiable signals of the function of various brain structures (Okuma,'1963 ; Okuma et al., 1963; Hayashi et al., 1964). Focal as well as 'generalized seizure discharges in epileptic patients were also recorded during nocturnal sleep in order to investigate both the alteration in incidence of seizure discharge and the change of nocturnal sleep pattern of epileptics.

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As a preliminary experiment, the change in experimental seizure discharges in the neocortex, amygdala and hippocampus induced by application of convulsant drugs such as strychnine was observed in chronically implanted cats during different stages of natural sleep, including the period of the S-A stage. The mode of change of the seizure discharge, especially in its incidence. during different stages of sleep seemed to be determined mostly by the intensity of the seizure discharge. That is, when the effect of strychnine was strong, the neocortical seizure discharge showed a slight enhancement during the spindle and slow wave stages and a marked enhancement during the S-A stage. The enhancement of spikes was also observed when the animal was excited. When the effect of strychnine was intermediate, the change in the number of seizure discharges during different stages of sleep was less marked, The weak strychnine discharges, on the contrary, were suppressed during both the arousal and S-A stages while it was enhanced during the spindle and slow wave stages. When the effect of the convulsant drug was strong, the experimental seizure discharge in the amygdala and hippocampus remained almost uninfluenced during the different stages of sleep, or showed a slight enhancement during both the excited stage and S-A stage. The weaker seizure discharges in those structures showed enhancement during the spindle and slow wave stages but were suppressed almost completely during both the arousal and S-A stages. Thus, no significant difference was found between the neocortical and limbic structures, as far as changes of the firing pattern of the strychnine discharge during a cycle of sleep were concerned. The alteration in the incidence of strychnine seizure discharge in the neocortical and limbic structures during different stages of sleep is summarized schematically in Table 1. A similar observation was made on the alteration of chronic focal seizure discharge produced by local injection of alumina cream (Okuma, 1963; Hayashi et al., 1964). The fluctuation in the number of seizure discharges (focal spike) during various stages of natural sleep was classified tentatively into 4 types (Fig. 9b). Type I: the seizure discharge was suppres5ed during arousal and S-A stages, and enhanced during S-1 (spindle) and S-2 (spindle and slow) stages. Occasionally spikes appeared in bursts on an otherwise silent background activity during arousal and S-A stages (Type 1'). Type IZ: the seizure discharge showed enhancement during the excited arousal (E) and S-A stages, particularly in the latter, and did not exhibit significant change during the"S-1 and S-2 stages. Occasionally the number of the seizure discharges diminished markedly during the S-1 and S-2 stages (Type TI'). Type ZZZ: the seizure discharge'wasmabsent (Type 111) or very low in number (Type 111') during arousal, began tomappearwinthe S-1 and S-2 stages and showed marked enhancement during the S-A stage. Type ZV: the number of seizure discharges was not significantly influenced by:the shift of sleep stages. This type was observed when the seizure dischargelwas too strong to be influenced by the sleep process. Type 1 was observed when the strength of the seizure discharge was weak, whereas Type TI was seen when it was fairly strong. The shifts from Type I to Type I1 and from Type I1 to Type I were frequently observed in the same cat in the course of References p. 2281229

2 24

T. O K U M A A N D H . A K I M O T O

TABLE I SCHEMATIC REPRESENTATION O F THE I N C I D E N C E O F SEIZURE DISCHARGES I N D I F F E R E N T S T A G E S O F SLEEP I N T H E C A T A N D M A N

v

2

,

T

a

+ f t

+

+

development of alumina cream foci and its suppression by anticonvulsant medication. Type 111 was common to both neocortical and limbic seizure discharges, but it tended to be more frequently observed in the neocortical seizure discharges. These types of change of seizure discharge during sleep almost corresponded to those of strychnine spikes mentioned before except for Type 111. Further details of the difference between the neocortical and limbic seizure discharges during sleep are now under investigation. The epileptic seizure discharge in various types of epileptic patient also showed significant changes in the incidence, distribution and wave form during different stages of nocturnal sleep. In petit ma1 with 3 c/s spike and wave paroxysm, a definite and constant correlation was found between the depth of sleep and the modifications of paroxysmal seizure discharge in the EEG (Taen et al., 1962; Kazamatsuri, 1964). The typical 3 c/s spike and wave paroxysm appeared in the stage of wakefulness and occasionally during the S A stage. As deep deepened, the regular rhythmicity of the seizure discharges disappeared, their duration shortened and at the deepest stage of sleep they were localized only in the frontal region. However, they always remained bilateral and synchronous. During the S-A stage, seizure discharges disappeared almost completely except for the occasional appearance of the rhythmic spike and wave paroxysm

NEURAL MECHANISM OF SLEEP

225

similar to those of the arousal stage. The 3 c/s spike and wave paroxysm during the S A stage was observed in about half of 21 cases of petit mal, and no paroxysmal discharge was found in the remainder. These findings seemed to indicate that the neurophysiological background of the S-A stage in the human subject was different from the stage of drowsiness, though the electrographic patterns in the drowsy and S A stages were similar. The sleep cycle and phase pattern of the petit ma1 patient did not show any significant difference from those of the normal control subject of the same age. The changes of focal cortical seizure discharge in temporal lobe epilepsy and other types of focal epilepsy were also investigated during nocturnal sleep (Fujimori et al., 1964). The mode of alteration of incidence of focal seizure discharges in different stages of nocturnal sleep were classified into 4 types. Type I: the number of focal spikes increased as sleep deepened, and the highest incidence was found during moderately deep sleep with spindle and S-waves. Most of the focal temporal spikes found in psychomotor epilepsy belonged to this type. Type 11: the number of seizure discharges increased as sleep deepened but spikes were completely suppressed in the S-A stage. Type III: the incidence of the focal spike was fairly high even during the arousal stage, increased further in the drowsy stage and showed marked enhancement during the S-A stage. Type IV: no consistent correlation was found between the number of focal spikes and the depth of sleep. As to the change in the distribution of focal seizure discharges, the focal single spike observed in the arousal state tended to spread to the same hemisphere and also to the other hemisphere as sleep deepened. Further, the nocturnal sleep cycle pattern of the temporal lobe epileptics was more irregular and shallower than those of normal subjects. The mode of change of the seizure discharge in different stages of natural sleep mentioned above seems to agree with the authors’ findings on the changes of evoked potentials in the specific and non-specific thalamocortical systems during sleep in the cat mentioned in the preceding paragraph. That is, the type of seizure discharge which showed enhancement during the arousal and S-A stages such as strong strychnine spike, alumina cream spikes and those of the epileptic patients, seems to correspond to the enhancement of evoked potentials in the specific thalamocortical systems (cf. the potential on the visual cortex evoked by a single shock on the optic tract) during the same stages of sleep. The type of seizure discharges that were suppressed during the arousal and S-A stages and enhanced during the s-l and s-2 stages, such as weak strychnine and other kinds of focal spikes, seemed to correspond to the change in amplitude of evoked potentials in the non-specific thalamocortical system. That is, the recruiting responses were enhanced during the spindle and slow wave stages and returned to the lcvel of the arousal stage during the S-A stage. The neocortical and limbic seizure discharges seemed to show a similar type of alteration in firing pattern during different stages of sleep. The authors, however, have the impression that the type of seizure discharge that is suppressed in the arousal stage and enhanced during the S-A stage is more frequently observed in the seizure discharge in the neocortex than in that of the limbic structures. Refermces p . 2281229

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( 5 ) Polygraphic study on the nocturnal sleep of various neurological and psychiatric

diseases A polygraphic study on the nocturnal sleep in different diseases of the central nervous system has been made for the purpose of diagnosis and also of investigation of the neural background of the diseases. As a disease with disturbance of sleep mechanism, cases with narcoleptic syndrome were studied polygraphically with special reference to hypnagogic hallucination and cataplectic attack (Jimbo and Takahashi, 1963; Takahashi and Jimbo, 1963). In all night sleep records of narcoleptics, it was noticed that the appearance of the S-A stage was less regular than in normal control subjects. The fact that in narcoleptics the S-A stage frequently appears immediately after the onset of sleep (Rechtschaffen et al., 1963) was confirmed in 8 out of 10 narcoleptic patieilts. The deepest stage of sleep, the &stage, was usually lacking in narcoleptics, and the patient woke frequently during the night, showing disturbance of sleep rhythm. Hypnagogic hallucinations appeared in the S-A stage or in the stage close to it. During a cataplectic attack, EEG showed a shift from low voltage fast activity to the a dominant pattern and further to the slower waves, showing a slight fall in the level of cerebral vigilance. Reduction in the pulse rate and respiratory inhibition were also observed during cataplexy. Sleep paralysis of narcoleptics might be considered a cataplectic attack induced during sleep by emotional factors such as anxiety and fear due to hallucinations. As to the influence of psychotropic drugs on the nocturnal sleep pattern of narcoleptic patients, imipramine (50 to 75 mg orally), chlorpromazine (25 mg orally) and trifluoperazine (4 mg orally) had been given to 6 typical narcoleptics with severe hypnagogic hallucinations, and polygraphic recordings of various physiological factors were made throughout the night (Jimbo et al., 1963). The administration of imipramine resulted in a significant decrease in the incidence of the S-A stage, including that occurring at the onset of sleep, and also a decrease in the hypnagogic hallucinations in the first half of the night’s sleep. The EEG depth of sleep tended to fluctuate, the patient remaining in a relatively light stage of sleep and waking frequently. The percentage of time spent at the drowsy pattern stage without rapid eye movements increased markedly under imipramine compared with the control. Chlorpromazine produced no change in the appearance of the S-A stage and resulted in a slight decrease i.n the occurrence of hypnagogic hallucinations, whereas the patient’s emotional expressions such as verbal and motor responses to the hallucinations were markedly alleviated. The percentage of the stage with spindle and slow waves became higher than that of the control. In the sleep records following the administration of trifluoperazine, the way in which the S-A stage and body movements appeared and lasted was almost the same as that of the control, while the hypnagogic hallucinations were significantly inhibited. A polygraphic study on the nocturnal sleep of schizophrenics has also been in progress (Azumi, 1964). It was found that the sleep cycle and phase pattern of typical hebephrenic patients showed no significant difference from those of control adults.

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SUMMARY

The neural mechanism of sleep has been investigated in the authors’ laboratory from several different aspects, and the results were summarized in the present article. (1) As to the electrographic pattern of different brain structures during sleep, the low voltage fast neocortical patterns of cats during arousal and activated sleep were similar, though there might exist some subtle difference between the two. The hippocampal electrogram showed more regular and faster rhythmic activity during activated sleep compared with those in the arousal stage. The electrographic pattern during sleep of the monkey seemed to have intermediate characteristics between the cat and man. (2) The evoked potentials in the specific system induced by direct electrical stimulation of the brain decreased in amplitude during the stage with slow background activity and showed an amplitude equal to or higher than the arousal state during activated sleep. The amplitude of the evoked potential was particularly large during the period of rapid eye movements. Evoked potentials in the non-specific thalamocortical system such as recruiting response were enhanced in the slow wave stage of sleep and suppressed during the activated sleep stage. The evoked cortical potential induced by electrical stimulation of the peripheral skin showed enhancement during the arousal and activated sleep stages, whereas those of the auditory cortex induced by click stimulation tended to be suppressed during the same sleep stages. It seemed to be pertinent to suppose that during the activated sleep stage not only the spontaneous electrographic activity but also the excitability of the cerebral cortex to the specific afferent stimuli are on the same level or higher than those in the arousal stage. (3) Two kinds of sleep rhythm, fast and slow, were observed. The ‘sleep phase’ was defined as an assembly of several ‘sleep cycles’. With continuous polygraphic recordings it was found that the cat has polyphasic, the monkey mono- or diphasic and the human monophasic types of sleep. The sleep cycle pattern was easily modifiable but the sleep phase pattern seemed to be more resistant to external modifying influences. (4) As to the effect of psychotropic drugs on the sleep pattern, imipramine tended to suppress the occurrence of activated sleep. A chronic administration of relatively high doses of chlorpromazine also decreased the percentage of activated sleep in cats, but a single dose of 50 mg tended to increase the same stage in the human subjects. Chronic administration of methamphetamine in the cat produced seizure discharges in the amygdala and hippocampus, but the modification of the sleep pattern in the addicted cat was rather slight. (5) Changes of epileptic seizure discharge during different stages of sleep were studied in cats and human epileptic patients. As to the experimental seizure discharges in animals induced by strychnine and alumina cream, the weak seizure discharges were suppressed during arousal and activated sleep stages, whereas the strong ones tended to be enhanced during the same stages. The seizure discharges of the human Rrfrrrnws p . 2281229

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epileptics were classified into several types according to the mode of occurrence during different stages of sleep. (6) The sleep pattern of narcoleptic patients was studied polygraphically, and the effect on it of psychotropic drugs was also investigated.

REFERENCES T., KURIHAKA, M., FUJIYA, Y . , IWAKI,K., TOYODA, J., KAZAMATSURI, H., AKIMOTO, H., NOGUCHI, AND SUZUKI, Y., (1963a); Psychotropic drugs-and the mechanism of sleep, a polygraphic study, Psychiut. Neurol. jup.,_65,149-150. AKIMOTO, H., TAEN,S., TOKUDA, Y . , KAZAMATSURI, H., KIKUCHI, S.,-ANDFUJIMVRI, M., (1963b); Studies on nocturnal sleep of epileptics (Part 11). Psychiut. Neurol. jup., 65, 121. AKIMOTO, H., AND-TOYODA, J., (1963); The etfects of psychotropic drugs on human nocturnal sleep EEG. (ll)_Phenothiazine group. Proc. XIIth Ann. Meet. Jup. EEG Soc., 179-180. AKIMOTO, H., YAMAGUCHI, N., OKABE, K., NAKAGAWA, T., NAKAMURA, I., ABE,K., TORII, H., AND MASAHASHI, K., (1956); On the sleep induced through electrical stimulation on dog thalamus. Folia psychiut. neurol. jup., 10, 117-146. AZUMI, K., (1964); A polygraphic study on the nocturnal sleep of schizophrenics with special reference to the paradoxical phase. Proc. XIIlth Ann. Meet. Jnp. EEG SOC.,In the press. DEMENT, W., (1958); The occurrence of low voltage fast electroencephalogram patterns during behavioral sleep in the cat. Electroenceph. clin. Neurophysiol., 10,291-296. D ~ M E NW., T , AND KLEITMAN, N., (1957); Cyclic variations in EEG during sleep and their relation to eye movements, body motility, and dreaming. Electroenceph. clin. Neurophysiol., 9, 673-690. FUJIMORI, M., KAZAMATSURI, H., TAEN,S., TOKUDA, Y . , AND KIKUCHI, S., (1964); Studies on nocturnal sleep of epileptics (Part I V ) . Proc. XIIIth Ann. Meet. Jup. EEG Suc., In the press. GIBBS,F. A., AND GIBBS,E. L., (1950); Atlas of EIectroencephulogruphy. Vol. I. Cambridge, AddisonWesley Press. HAYASHI, A., OKUMA, T., AND FUJIMORI, M., (1964); The alteration of seizure discharges (alumina cream) in the neocortex and limbic structures during natural sleep in the cat. Proc. XIIIth Ann. Meet. Jup. EEG SOC.,In the press. JIMBO, S., AND TAKAHASHI, Y., (1963); Polygraphic study on the all night sleep pattern of the narcoleptic patients, with special reference to the hypnagogic hallucination. Psychiur. Neurol. jup., 65, 114-1 15. JIMBO, M., TAKAHASHI, Y., AND SUZUKI, J . , (1963); Polygraphic studies of nocturnal sleep of narcoleptics. (11) The effect of some psychotropic drugs on the hypnagogic hallucinations. Proc. XIIih Ann. Meef. Jup. EEG SOC.,182-185. KAZAMATSURI, H., (1964); Electroencephalographic study of petit ma1 epilepsy during natural sleep. (Study on nocturnal sleep of epileptics: Part I). Psychiut. Neurul. jup., 66,650-679. KOGA,E., (1960); The study of sleep by polygraph. (1) Normal sleep. Psychiut. Neurol. jup., 62, 125-1 48. KOGA,E., (1963); Sleep EEG and other physical processes. Proc. XIlth Ann. Meet. Jnp. EEG SOC., 34-37. NAKAGAWA, Y., (1964); Alteration of evoked potentials of human subjects during nocturnal sleep. Proc. XIIIth Ann. Meet. Jup. EEG Soc., In the press. OKLJMA, T., (1962); Neurophysiology of sleep. Proc. XIth Ann. Meet. Jup. EEG SOC.,8-12. OKUMA, T., (1963); Arousal and sleep reactions in the neocortex; the neurophysiological background of the 'activated sleep'. Proc. XIIth Ann. Meet. Jup. EEG Soc., 27-30. OKUMA, T., A N D FUJIMORI, M., (1963); Electrographic and evoked potential studies during sleep in the cat. (The study on sleep I). Foliu Psychiut. Neurol. jup., 17, 25-50. OKUMA, T., AND FUJIMORI, M., (1964); Unpublished data. OKUMA, T., FUJIMORI, M., AND HAYASHI, A., (1964a); An electrographic study on the modification of the sleep cycle pattern by repeated arousal stimulation in both man and cats. (The study on sleep 111). Foliu Psychiut. Neurol. jup., 18, 63-77. OKLJMA, T., FUJIMORI, M., AND HAYASHI, A., (1964b); Evoked potential study during natural sleep in the cat. Proc. XIIIth Ann. Meet. Jup. EEG SOC.,In the press.

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OKUMA, T., FUJIMORI, M., A N D SEKIGUCHI, M., (1961); A study of evoked potentials during sleep in cats, with special reference to the activated sleep. Proc. Xrh Ann. Meet. Jup. EEG SOC.,53-57. OKUMA, T., HAYASHI, A,, A N D FUJIMORI, M., (1964~);An electrographic study on the changes of experimental seizure discharges induced by local application of convulsants in the neocortex and limbic structures during natural sleep in the cat. (The study on sleep TI). Foliu Psychiui. Neuvol. jap., 18, 44-62. OKUMA T., , AND SASAKI, K., (1964); The electric activity of the brain and sleep cycle pattern during natural sleep in the monkey. Proc. XIIIth Ann. Meet. Jap. EEG SOC.,I n the press. OKUMA, T., A N D SEKIGUCHI, M., (1962); Neurophysiology of sleep. Clin. Psychiut., 4,807-818. E. A., DEMENT, W. C., MITCHELL, S. A,, AND FISHER, C., (1963); RECHTSCHAFFEN, A,, WOLPERT, Nocturnal sleep of narcoleptics. Electroenceph. clin. Neurophysiol., 15, 599-609. T., KAZAMATSURI, M., KIKUCHI, S., AND FUJIMORI,M., (1962); Polygraphic TAEN,S., TOKUDA, analysis of spike-wave complex of petit ma1 epilepsy in all night sleep record. Bruin and Nerve, 14, 299-305. TAKAHASHI, Y., AND JIMBO,M., (1963); Polygraphic study of narcoleptic syndrome, with special reference to hypnagogic hallucination and cataplexy. Proc. Joint Meet. Jup. Sac. Psychiut. Neuvol. Anier. Psychiut. Ass., 343-347. TAKANO, R., UCHINUMA, Y., ANDO,N., HIRAI,T., KOGA, E., NAKAGAWA, S., YUHARA, A., AND ENDO,S., (1963); Nocturnal sleep of children. (I) On rhythmical waves. Pvoc. XIIth Ann. Meei. Jup. EEG SOC.,51-52. UCHINUMA, Y., TAKANO, R., ANDO,N., HIRAI,T., KOGA,E., NAKAGAWA, S., YUHARA, A., AND ENDO,S., (1963); The nocturnal sleep of children. 01) On developmental aspects. Pvoc. XIIrh Ann. Meet. Jap. EEG SOC.,187-188.

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Studies on the Paradoxical Phase of Sleep in the Cat TOSHIHIKO TOKIZANE Department of Neurophysiology, Institute of Brain Research, Faculty of’Medicine, University of Tokyo, Tokyo (Japan)

INTRODUCTION

At present the so-called paradoxical phase of sleep, characterized by various specific phenomena observed in the EEG, motor and autonomic activities, is attracting the interest of brain scientists. For the last 2 years our laboratory has been engaged in extensive analyses of this unique sleep state in the cat. The results obtained will be briefly reported in this paper. Part 1 will describe the analysis of the spinal motor activities and part 11 polygraphic analysis of the autonomic activities. The first half of part I11 will relate an attempt to induce the paradoxical phase of sleep by short-chain fatty acids in the chronic cat, and in the second half the effects of these fatty acids in the acute state will be described. Finally 1 will comment on possible physiological mechanisms of the paradoxical phase of sleep. Many different terminologies have been suggested to designate what appears to be the same sleep state, i.e. the so-called paradoxical phase of sleep; for example, low voltage EEG sleep, rhombencephalic sleep, activated sleep, desynchronized sleep, deep sleep, etc. When the Symposium of Sleep was held in September 1963 at Lyon, I (Tokizane, 1963) suggested the use of new terms to represent 2 states of sleep: ordinary sleep may be named ortho-sleep and the newly-found sleep para-sleep. Para means ‘functionally disordered’. Since these suggestions are not yet rejected, these terms will be used in this paper. P A R T I . ANALYSES OF SOMATIC ACTIVITIES

( I ) Flexor reflex activities*

As is well established (Jouvet, 1962, etc.) the somatic activities of the cat during parasleep are characterized by the silence of the ‘tonic’ activity of, for example, neck muscles, and the appearance of the ‘phasic’ twitch-like activity of, for example, facial, ocular and forelimb muscles. Spinal monosynaptic and polysynaptic reflex activities were analyzed. Since the change of the former had been described elsewhere, its detail

*

By Y . Kidokoro and K. Kubota.

PARA-SLEEP

23 I

was not mentioned in this article. During para-sleep homonymous and heteronymous spinal monosynaptic reflexes (MSR) are depressed in both flexors and extensors of the hindlimb (Giaquinto el al., 1964; Gassel et al., 1964; Kubota et al., 1965). Furthermore, this MSR depression is exerted on both fast and slow components of the extensor MSR, in other words, MSRs of both tonic and phasic muscles. The polysynaptic reflex (PSR) of flexor muscles also becomes less excitable during para-sleep. Polysynaptic contraction of the gracilis muscle evoked by high cycle stimulation of the muscle nei ve (posterior biceps-semitendinosus nerve) was depressed during the parasleep state (Giayuinto et al., 1964). In the present study the reflex activity of the forelimb flexor muscles was evoked by a single shock to the superficial radial nerve and compared in different states of sleep. Special attention was directed to the twitch-like activity of forelimb flexors. Observations were also made on the biceps femoris muscle. Methods In 20 adult cats a preliminary operation of the electrode implantation was done aseptically as described by Kubota et al. (1965). Screw electrodes were implanted for EEG recording in the cranial bones covering the somatosensory cortex. The neck EMG was recorded bipolarly via stainless steel electrodes. Similar stainless electrodes were implanted in the belly of the brachial muscle or biceps femoris muscle. Pairs of nerve electrodes as used by Kubota et al. were implanted in the superficial radial or the sciatic nerve of the same side. Two proximal electrodes were used for the stimulation (0.01 msec duration, 0.3-1 cycle/sec, and less than 5 V, the central one being negative). From the most distal electrode, several cm away from stimulating ones, the directly excited nerve potential was monopolarly recorded and utilized to determine the threshold of the nerve and further to ascertain the stability of the cesting reflex system. Stimulus intensity was represented as multiples of the threshold voItage ( x NT). At the periphery the nerve was crushed. Reflex muscle response was recorded monopolarly from the brachial or biceps femoris muscles. Reference electrodes for both muscle and nerve responses were the needles inserted into the subcutaneous tissue at the respective periphery. Nerve stimulation induced the negative or positive field potentials of the muscle origin in the nerve electrode. When a relatively large negative potential was recorded from the muscle electrode associating with the contraction of a given muscle, the potential was considered as excitation of the muscle and subjected to an analysis. Cervical or lower thoracic transection of the spinal cord was performed under ether anesthesia, in order to see the effect of the transection upon the reflex activity. Results Two kinds of refex responses. By superficial radial nerve stimulation at sufficiently strong intensity (more than 2 x NT), two kinds of well-separated reflex responses appeared in the brachial muscle of the intact chronic cat (Fig. 1A1). The initial response with a 5-7 msec latency is the so-called polysynaptic reflex (PSR). After the silent phase, the second potential follows. In different preparations, the latency of the second varied from 12 to 19 msec and the total duration was also variable, from 5 to References p . 266-268

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T. T O K I Z A N E A,

A2

Fig. 1. Abolition of the second component of the flexor reflex (SBSR) by spinal transection. 11.1A1 and AZ 3 superimposed EMG responses of the 1. brachial muscle were evoked by 0.3 cycle/sec stimulation of the 1. superficial radial nerve at intensity of 3.1 x NT during the awake state. After A1 was recorded, the spinal cord was transected totally at the C1 level under ether anesthesia. Xylo-

caine was injected into the cord to help the transection. Two hours after the termination of ether inhalation, Az was recorded in the awake state. The artificial respiration was continued. In B1 and BZ superimposed traces of EMG of the 1. biceps femoris muscle were evoked by sciaticnerve stimulation (0.3 cycle/sec, 1.80 x NT). B1 was rccorded when the animal was awake. After this, the cord was transectcd at the lower thoracic level. Bz was recorded in the awake state 2 hours after stopping the ether. Upward deflection indihtes the negativity in this and succeeding figures unless specially mentioned.

20 msec. For the following 2 reasons the second potential was considered as the spino-bulbo-spinal reflex (SBSR) (Shimamura and Livingston, 1963). Firstly, both latency and duration of the response were approximately identical with those of the SBSR in the acute decerebrate cat. Secondly, this potential was completely abolished by the acute high cervical transection (2 cats), indicating that the supraspinal structure was indispensable for eliciting this response. Fig. 1A2 illustrates changes in the reflex of the brachial muscle after the spinal transection. After PSR and SBSR were recorded in the chronic intact awake state (Fig. IAl), the spinalization was doneat the C1 level. The response to the same stimulus parameters as in A1 is shown in Fig. 1Az. Although in the latter the PSR size was somewhat larger, no trace of the second potential was observed. When the flexor reflex activity was recorded from one of the hind limb flexors, that is, biceps femoris muscle, and the shock of an appropriate intensity was applied to the sciatic, peroneal, or tibia1 nerve, the second response was also noted after the initial PSR (Fig. 1BI). Consistent with previous observation (Shimamura et al., 1962) the latency of hindlimb response was longer (20-30 msec) than the brachial muscle response. This second potential was also abolished by acute and chronic spinal transection at the lower thoracic level (3 cats). Fig. 1 B2 illustrates the response after

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PARA-SLEEP

the lower spinalization in which the initial PSR remained and the second response was completely abolished. In the intact chronic cat, as well as in the acute spinal cat, occasionally a third response of small magnitude appeared (50 msec after the shock) of which the nature was not studied. Thus, it is shown that the second response of the biceps femoris muscle is also the SBSR. The PSR and SBSR were compared in the awake and 2 sleep states. Fig. 2 illustrates one example of changes of the flexor response (upper trace) and the nerve response (lower trace) evoked by stimulation to the superficial radial nerve at ortho- (A) and the succeeding para-sleep (B). In B the size of the PSR is smaller than in A. The SBSR is apparent in B, while it is not in A. The nature of the last EMG response of A is not known. In Fig. 3 both muscle and nerve responses were evoked by the single shock, and their magnitudes were plotted successively in the diagram during transition from orthosleep (left) to para-sleep state (right). Samples of oscilloscopic traces representing

I

10 m sec

I

B

Fig. 2. EMG response of the 1 . brachial muscle of cutaneous afferent origin at ortho-sleep (A) and para-sleep (B). Each consists of 4 superimposed responses evoked by the 1 . superficial radial nerve stimulation at a repetition of every 3 sec, its intensity being 2.73 X NT. The upper trace represents EMG of the 1. brachial muscle and the lower trace the nerve potential recorded from the distaI part of the 1 . superficial radial nerve. References p . 266-268

o PSR

L.8rachial EMG L.Sup.Rad.N.(3.20xNT)

SBSR

E

N

> Imi"K

EEG

EMG Fig. 3. PSR and SBSR changes during transition from the ortho- to para-sleep state. The amplitudes of PSR(0) and SBSR(0) of the 1. brachial muscle which were evoked every 2 sec by 1. superficial radial nerve stimulation at 3.20 x NT intensity are plotted continuously. At the bottom the spindle burst phase in EEG, tonic neck EMG and rapid eye movements are indicated by bars. A and B represent specimen records selected from underlined parts below the diagram, the upper and lower traces being respectively the muscle and nerve responses. Sensitivity in A and B: 1 .0 mV for the upper trace and 0.1 mV for the lower.

zm

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0

A

1.37

P

4

A

n

2.65

I

Fig. 4. The polysynaptic (PSR) and spino-bulbo-spinal (SBSR) activities during ortho-sleep (O), para-sleep (P) and awake state (A). Series of responses are illustrated a t 4 different stimulus intensities, from top to bottom, 1.37, 1.90, 2.65 and 3.66 x NT. I n each record the upper trace shows the EMG response of the 1 . brachial muscle and the lower trace the potential of the superficial radial nerve evoked a t 1 cycle/sec for at least 4 sec. Voltage calibration, 0.3 mV, small bar for upper trace and large bar for lower trace. Time, 5 msec. Two responses are represented at P, 2.65 x NT. In A, the top response was recorded when the animal was moving around. The lower 3 were from relaxed awake state. Except for the top right response, all responses are included in the plots in Fig. 5.

the respective states are shown in the above (A and B, from responses underlined in the diagram). In the control ortho-state, a PSR of about 1.2 mV (0) was evoked with moderate amplitude fluctuation, and a small or no SBSR ( 0 ) followed. After this phase the neck EMG decreased gradually to zero and the para-sleep state developed in which the PSR was smaller, often disappearing, and a large SBSR was evoked either with or without PSR. During para-state no correlations were found between the sizes of SBSR and PSR. Often both PSR and SBSR disappeared completely. As will be noticed in some traces of B, a smaller SBSR was evoked with longer latency. Figs. 4 and 5 show relationships between the stimulus intensity and sizes of the PSR or of the nerve potential at 2 states of sleep and waking. In the upper diagram of Fig. 5, average sizes of the PSR were plotted as a function of multiples of the nerve threshold. Filled circles and crosses represent, respectively, the ortho- or para-state which References p.

266-268

236

T. T O K I Z A N E

. . . . 0

I

0

.

..

Fig. 5 . Relation between stimulus intensity and PSR amplitude of the 1. brachial muscle (upper diagram) or the potential of the I . superficial radial nerve (lower diagram). In the upper diagram open circles are from the relaxed awake state, filled circles from the control ortho-sleep and crosses from the para-sleep state. Each point represents the average amplitude of 5 responses evoked by 1 cycle/ sec stimulation. Crosses were recorded during 2 episodes of the para-sleep in one day's experiment. In the lower diagram, filled circles represent the size of the potential of the superficial radial nerve in per cent during the recordings of the PSR response, 100% being 180 pV.

occurred twice during one day's experiment. The potentials of the superficial radial nerve are plotted in the lower diagram against the nerve threshold on the abscissa. They were obtained from the same series of recordings as in the upper diagram. During para-sleep the PSR became smaller, direct activity of the nerve being uninfluenced. Fig. 4 illustrates specimen records of the PSR depression and the SBSR increase during para-sleep at different stimulus intensities. The stimulus intensity was increased gradually from top to bottom as shown at the left column ( x NT). The left column (0) was recorded in the control ortho-state and the middle column (P) was from the para-sleep state. Each pair includes EMG responses (upper) and nerve recordings (lower) evoked by 1 cycle/sec stimulation for 5 sec. The latter were included simply to show the size of the nerve response. In all records of para-sleep, the PSR was smaller than in the corresponding responses of the ortho-state. In the para-state the SBSRs were evoked at 1.90 and 2.65 x N T but they were almost or completely absent in the ortho-state. During para-sleep a clear SBSR was more easily evokable at higher intensity of stimulation, usually more than 2 x NT. In the ortho-state the threshold for eliciting the PSR was about 1.2-1.3 x N T where 30-40 of the low threshold cutaneous fibers were excited. With an increase in the number of the excited fibers, the PSR size during ortho-sleep increased until cutaneous fibers were excited almost maximally (about 3 x NT). Above 2.5 x NT intensity, increase in PSR was not marked, as illustrated. The maximal intensity to evoke the total of low threshold cutaneous fibers of the

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illustrated sample (3 x NT) was smaller compared with an earlier report (more than 4 times) (Pompeiano and Swett, 1962a, b, etc.). A single shock at an intensity higher than 3.5 x N T wakened the animal both in behavior and EEG for a while. At the right of Fig. 4, except the top record, are illustrated the responses when the animal was awake in EEG but not showing apparent movements. The top record was obtained when the animal was moving around. In the awake state a larger PSR could be evoked but the size fluctuated more dominantly. Therefore the average value was not greatly different from that of the ortho-state. In Fig. 5 PSR responses in the awake state, which occurred before and after the para-sleep recordings, are included and represented by open circles. Thus, in agreement with Giaquinto et al.'s observation of the PSR of the knee flexor muscle, during para-sleep the PSR was depressed. It appears that in the PSR depression a similar depressive mechanism from higher structures as in the MSR depression is involved. Contrary to the PSR depression, the SBSR is released during para-sleep. It is likely that a similar mechanism is in action which elicits the jerky movement in facial and other muscles to release SBS activity of the low threshold cutaneous origin. The depression of the PSR and release of the SBSR during parasleep were also confirmed in the biceps femoris muscle where the reflexes were evoked by sciatic, peroneal or tibia1 nerve stimulation at an intensity to excite the so-called 'FRA' fibers. In the MSR studies, during para-sleep the extensor MSR was always depressed, while in flexor MSR it wa4 occasionally observed that the abortive large MSR was evoked only once or twice in a whole series of para-slzep episodes, superimposed upon the depressed MSRs (Kubota et at., 1965). Fig. 6 illustrates an example of flexor MSR depression with polygraphic recordings. In the middle of the polygraph, the para-sleep phaqe developed. The average size of MSR during this phase was smaller than in the preceding ortho-state (No. 1-24). The response No. 71 was larger than the average for the ortho-state, which occurred coinciding with the eye movement. It may be possible to explain the large flexor MSR during para-sleep, should it occur temporarily associating with the exaggerated SBSR activity. The brachialis SBSR was rarely evoked in the ortho-sleep and relaxed awake state. When the animal was put into the experimental box for the first time i n a day's experiment, and especially when the animal was attentive, the SBSR was elicitable. Its size was as large as during para-sleep but it quickly adapted after, say, one or two responses. When stronger stimulation was applied to awaken the animal, then the SBSR occasionally appeared responding only to the initial several shocks. The relation between the SBSR activity and the animal behavior waits further analysis. (11) Excitability changes of the motoneuron"

During the para-sleep phase both the MSR and PSR are depressed, while the SBSR are exaggerated. A question arises as to whether the postsynaptic membrane of the motoneuron becomes less excitable or not. To test its excitability, a method was used

*

By Y . Kidokoro and K. Kubota.

References p . 266-268

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Fig. 6. The MSR in the peroneal nerve in sleep. Magnitudes of the flexor MSR evoked by repetitive sciatic nerve stimulation (0.3 cycle/sec, 1.5 x NT) are plotted during transition from ortho-sleep to para-sleep and to the awake state. Upper polygraphic recordings show, from top to bottom, EEG of somatosensory area (MC), neck EMG, eye movement (EYE) and respiratory rhythm (RESP). Samples of oscilloscopic responses are represented in the middle. Numbers above the pictures indicate the number in the diagram.

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to stimulate the spinal cord so that the motoneuron may be excited directly. Copper wires, insulated by polyurethane except the very tip (90-125 p diam.), were thrust blindly into the ventral part of the cord (L5-L7) in a dorso-ventral direction and implanted chronically. They were fixed by stitching to the pia covering the dorsal surface of the cord at L7-Sl. Another wire was implanted at the dorsal surface at S2, and used as reference ( 1 50 p diam.). Activities of ankle flexor (tibialis anterior, extensor digitorum longus) and extensor (soleus, gastrocnemius and plantaris) muscles evoked by the intraspinal stimulation were recorded by two stainless steel needles with a separation of 1-3 mm. They were insulated by polyurethane except the slant surface of the tip. Dorsal roots were cut bilaterally from L5 to S2. Appropriate stimulation of the cord (0.1-0.3 msec, less than 9 V) elicited the single motor unit activity of the polyphasic shape (see right top of Fig. 7). It was possible to record the same single unit for several hours without any distortion of the potential shape. For stabilized recording it was convenient to use needle electrodes with crisps or small knobs in their shaft made of insulating material. The ‘single’ motor unit activity was identified by its appearance in all or none manner by slight adjustment of the stimulus intensity for the cord. The unit activity evoked by the direct excitation of the motoneuron is assessed from the following procedures. After the experiment the laminectomy was performed and the ventral roots of L6, L7 or S1 were mounted for stimulation. The shortest latency from the cord entry of these ventral roots to given muscles was measured. This value was compared with the latency of the single motor unit by the cord stimulation obtained in the chronic state. If the difference of these two values was less than 0.4 msec, that motor unit activity was considered as a directly excited one (Renshaw, 1940; Lorente de N6, 1935). Or alternatively, during or after the experiment the sciatic nerve was stimulated supramaximally and both the EMG response and the antidromic field potential of the motoneuron were recorded. The former was picked up from the same electrodes for single motor unit recording and the latter was recorded from the intraspinal electrode used to elicit the single motor unit activity. Within 0.4 msec the motor unit would not be excited transsynaptically by the cord stimulation, being too short to allow one synaptic delay within the cord (Renshaw, 1940; Lorente de N6, 1935). The electrode position within the cord was confirmed by Kluver-Barrera staining after the sacrifice. Stimulus intensities needed to evoke the same single motor unit were compared during two of the sleep and awake states. The threshold is represented by the arithmetic mean between the highest voltage evoking no activity in 10 trials of 1 cycle/sec repetitive stimulation and the lowest voltage evoking 10 responses by the same stimulation. The current intensity of the shock was measured by the voltage drop across the 1 k Q resistor (100 or 50 Q) inserted in series with the output of the TSU (NIHONKOHDEN TYPE MSE3; output impedance, less than 400 Q) and always monitored on the oscilloscope screen (Tektronix 502). Fig. 7 illustrates the excitability change in both the flexor and extensor motoneurons during transition from ortho- to para-sleep. Threshold changes were compared. As illustrated in the right top records, latencies of flexor (Fl) and extensor (El) motor units from the cord were 3.0 and 2.6 msec, respectively. Each unit was evoked at the Rrfermccs p 266-268

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Fig. 7. Excitability changes of ankle flexor and extensor (F and E) motoneurons during a series of ortho-, para-sleep, awake and again ortho-sleep states. The ventral spinal cord at L7 was stimulated cathodally (0.1 msec, I cycle/sec for 10 sec). Single motor unit activities are recorded bipolarly from those of ankle flexors (FI) and extensors (El). The threshold value in the ortho-state is taken as standard for the ordinate axis and the relative stimulus intensity is represented (threshold for F, 2.74 V and for E, 2.83 V). To the left is illustrated the ortho-state as judged from bars of the bottom, representing neck EMG, spindle burst in EEG and eye movements. The middle area between two vertical broken lines indicates the para-sleep phase. After the experiment E2 and F 2 at the right top were recorded, monopolarly and simultaneously, from ankle extensor and flexor muscles by bare needles during supramaximal stimulation of L7 ventral root (downward negative). Time, 2 msec for E l and FI, 1 msec for E2 and F2. Voltage, 50 pV for El and F1, and 1 mV for E2 and F2. In El response, there occurred another small single unit activity with the same latency, which also showed a threshold increase during para-sleep. E and F responses were recorded alternately from a 2-beam oscilloscope. Appropriate dorsal roots were cut bilaterally.

intensity near the threshold (1 cycle/sec). Sometimes they failed to respond. After the experiment the latencies from the L7 ventral root at its entry were measured, the values being 2.7 msec for flexor (F2) and 2.4 msec for extensor unit (E2). The differences in the latencies between ( I ) and (2) in each unit were 0.3 msec (E) and 0.2 msec (F), respectively, and these values were too short to be ascribed to the transsynaptic excitation. These units must be considered as directly excited. Threshold changes of these units during sleep states were represented in per cent threshold for the control ortho-state. When a unit responded 10 times to 1 cycle/sec stimulation of 10 sec duration, the F.I. (firing index) is 1.0 (0).If it did not respond at all, the F.I. is 0 ( x 1. If it responded to some of the 10 shocks, the F.I. is intermediate (A).As illustrated, thresholds were higher during para-sleep in both F and E units. In the E unit, during para-sleep a voltage as high as 13 "/, failed to evoke the response. I n this phase the F unit did not respond to the stimulus 5 % highei than the control. In the ortho-state after the para-sleep which continued for 8 min, thresholds returned to the control level (F unit 97 %,, E unit 103 %). In a number of observations (14 motor units of 6 cats) the largest threshold increase

PARA-SLEEP

24 I

during para-sleep was 30 %. The average value was 10 %. There was no difference in the threshold increase between flexor and extensor units. It was confirmed from the current reading that the increase of the threshold intensity during para-sleep is not due to the impedance decrease between the two intraspinal electrodes. N o motor units were found that showed the threshold decrease during para-sleep. There were a few motor units which did not show any shift of the threshold during para-sleep. This may be because the responding motor neurons are somewhat damaged or are located far away from the intraspinal electrode. Thus, it was shown that the lumbar motoneurons were less excitable in both flexor and extensor during para-sleep, as far as tested by its direct excitation. The threshold increase above mentioned would, most probably, reflect the hyperpolarization of the motoneuronal membrane. The term ‘membrane’ is meant loosely to include the axonal part and dendritic portions of the motoneuron (Porter, 1963).

A

0

Fig. 8. Antidromic focal potential of the motoneurons in the ortho-state (A) and para-sleep state (B). Supramaximal stimulation (0.01 msec, 1 cycle/sec, more than 20 times) was applied to the sciatic nerve just below the branching of the hamstring nerve. Reference was the dorsal part of the cord at S2. Voltage calibration, 100 pV. Time scale, 1 msec. Later rise in the response is the contamination of the evoked EMG of hindlimb muscles. Refirmcis p. 266-268

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(III) Antidromic .focal potential change* An antidromic focal potential of the motoneuron was evoked by single shock stimulation to the peripheral ncrve (sciatic, tibial or peroneal nerve) through implanted nerve electrodes, and compared in two stages of sleep. No change in the size of the focal potential was observed during para-sleep (4 cats). Fig. 8 illustrates the stability of the magnitude of the antidromic focal potential evoked by supramaximal stimulation of the sciatic nerve in ortho- (A) and para-sleep states (B). This finding indicates that the assumed membrane hyperpolarization during para-sleep, if it exists, is not sufficiently large to block the antidromic invasion of the motoneuron. ( I V ) Excitability test of’ the primary aferent terminal*

In section 11 the threshold increase of the directly excited motoneuron was described. The next question is whether the presynaptic inhibitory mechanisms are involved in

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Fig. 9. Excitability test of GI fibers during ortho-sleep (a) and para-sleep (b). Ventral quadrant of L7 spinal cord (left side) was stimulated and the quickest potential of the 1. tibial nerve conducted antidromically through the dorsal roots was recorded (upper trace). Responses were superimposed 10 times during the stimulation a t 1 cycle/sec. Bilateral ventral roots from L6 to S2 and contralateral dorsal roots from L6 to S1 were cut. A GI spike potential was evoked at 3 different stimulus intensities (A, B and C ) .C is the supramaximal response. The lower trace shows the current intensity of the shock stimulus in d-c recording. Subscripts a and b are paired responses in the ortho-state and parastate respectively. Voltage calibration at right top is for A and B. In C , sensitivities reduced to half.

*

By Y. Kidokoro and K. Kubota.

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the monosynaptic depression during para-sleep. Using similar intraspinal electrodes as used in the excitability test of motoneuron, the excitability of the primary afferent fibers was tested by measuring the potential size of the afferent fibers (Wall, 1958; Eccles et al., 1963a). Copper wires (polyurethane covered, 90-1 25 p diam.) were thrust horizontally from the contralateral lateral funicular part (L5-L7) to the ventral part of the cord. Contralateral dorsal and bilateral ventral roots were cut (L5-S2). By single shock stimulation of the spinal cord the quickest responses were recorded from the peroneal and tibial nerve (4 cats). The latency of the response was within 1.5 msec, indicating the conduction of the GI fiber. The GI potential thus evoked was compared in two states of sleep. Current intensity of the shock was simultaneously recorded. As illustrated in Fig. 9, no significant change in the spike size by a submaximal cord stimulation was observed in the tibial nerve. Nor was the threshold change observed. These were confirmed in the peroneal nerve. With this method, no excitability change of primary afferent fibers within the cord between the 2 sleep states was detected. One may argue that the cord was seriously damaged by the implanted electrodes or operative procedures and the excitability change test by single shock is not sufficient to detect the subtle membrane potential change of the primary afferent terminals or the shock is not adequately applied to the terminal where the polarization occurs. Since these possibilities are not eliminated, the presynaptic change during para-sleep is not completely excluded. But it should be emphasized here that, although evidence for presynaptic change was not obtained, the postsynaptic change of the motoneuron was well demonstrated. ( V ) Observation of the cord dorsum P wave"

If the primary afferent terminal depolarization (PAD) was associated with the MSR depression during para-sleep, the cord dorsum P wave will probably decrease its amplitude (Eccles, 1964). The P wave, as illustrated in Fig. 10, was recorded from the dorsal part of the cord via the implanted intraspinal electrode (polyurethane coated copper wire), and was compared between the 2 sleep states. It has been unsuccessful in recording the P wave of GI fiber origin. Fig. 10 shows the P wave evoked by excitation of Group I1 range fibers of the tibial nerve, and showed no apparent magnitude change between ortho- (upper) and para-sleep (lower). ( V I ) Pharmacology on the monosynaptic reflex during para-sleep and ortho-sleep * *

Among drugs which are known as influencing the activities of the monosynaptic reflex pathway, strychnine and picrotoxin were applied in the chronic state in order to obtain evidence for the synaptic mechanisms underlying the depression of the spinal * By A. Givre, Y . Iwamura, K. Kubota and Y.Niimi. * * By Y . Kidokoro, K. Kubota and H. Takamura. R r f e r m i i v p . 266-768

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Fig. 10. Positive potential associated with the primary afferent depolarization recorded from an implanted electrode in the dorsalmost part of the cord at L6. The wave was evoked by stimulation of the tibia1 nerve (1 cycleisec, 0.1 msec) at 2.8 times threshold which was presumably of FRA afferent fibers. The size was about 70% of the iuaximally evoked P wave by the single shock stimulation. Upper and lower traces, the response during ortho- and para-state, respectively.

monosynaptic reflex during para-sleep. If strychnine releases the MSR from its depression during para-sleep, this suggests that the depression is caused by the IPSP in the motoneuron, because strychnine is known to diminish selectively the IPSP of the motoneuron (Eccles, 1957; Kawai and Sasaki, 1964; etc.). If picrotoxin blocks the MSR depression during para-sleep, this suggests that the depolarization of the primary afferent terminal (PAD) is directly related to the MSR depression, because picrotoxin decreases selectively the PAD of various peripheral nerve origin (Eccles et al., 1963b). During administration of subtetanic doses of these 2 drugs it was confirmed that the cat could fall into the paradoxical phase of sleep. Direct effects of these drugs upon the sleep cycle were not studied systematically. Subcutaneous iiijection of strychnine nitrate (0.2-0.3 mg/kg, Mohan-yakuhin, Tokyo) produced for several hours the typical excitable state of the somatic activity to various stimuli such as the auditory ones. The sizes of the PSR and SBSR of brachialis and biceps femoris muscles became larger, their thresholds decreased. Occasionally spike activities were observed in the

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EEG traces. In this state the animal showed the phase of the para-sleep, although the preceding ortho-sleep phase was relatively short due probably to the strychnineinduced excitable state. Sizes of the MSR, peroneal and tibial, evoked by stimulus of the same parameter were compared between the para- and the preceding ortho-sleep states during strychnization. Fig. 11, A and B illustrates an example. The tibial (upper trace) and peroneal (lower trace) MSRs were evoked by the sciatic nerve stimulation (1.65 x NT, 0.3 cycles/sec). During para-sleep (B), the peroneal MSR was smaller than in A, and often disappeared. The tibial MSR disappeared except one smaller response. During para-sleep the threshold for MSR also increased as in the intact cat. And its increase was of a similar order. Thus, as observed in the intact state, the nonreciprocal MSR depression during para-sleep was observed in the strychnized states (5 para-sleep episodes of 3 cats). Picrotoxin also did not prevent the occurrence of the MSR depression during parasleep (0.2 mg/kg, KOSO Chemical, Tokyo). After the subcutaneous injection of the picrotoxin (3 episodes of 2 cats) the animal became somewhat restless and somatic activities were evoked in response to stimuli suchas touch. Salivation also often occurred. At this time, the SBSR became elicitable. The animal could fall into the para-sleep

AL I

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Fig. 1 I . Effect of strychnine (A, B) and picrotoxin ( C , D) upon the MSR during ortho- (A, C) and para-sleep (B, D). A, records of tibial (upper trace) and peroneal (lower trace) MSRs in ortho-state during strychnization (0.3 mg/kg subcutaneous injection 2 h 10 min previously). Shocks were applied to the sciatic nerve at 0.3 cycle/sec, 1.65 x NT for I 5 sec. B, records in para-sleep evoked by the same stimulus parameters as for A. In A and B, direct nerve responses are out of screen. C, during orthosleep the tibial MSR (high and low gain response) was evoked by 0.3 cycle/sec sciatic nerve stimulation at 1.33 x NT. Picrotoxin was injected subcutaneously I10 min previously. D, the same MSR during para-sleep. Time, 2 msec. Voltage scale, 100 p V . References p . 266-268

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state, though rarely. Fig. I 1, C and D illustrates the picrotoxin effect on the tibia1 MSR with 2 traces at different amplifications. The MSR was evoked by 0.3 cycle/sec at 1.3 x NT for 1.5 sec. During para-sleep (D) the MSR disappeared or was smaller than that in the preceding ortho-state (C). Five min after this para-sleep episode in which record D was taken, the generalized convulsion occurred, indicating that the drug was certainly effective. Depression was also confirmed in the peroneal MSR. Thus, a subtetanic dose of strychnine or picrotoxin did not prohibit the occurrence of the MSR depression during para-sleep in the intact chronic cat. It may be said that the presynaptic inhibition is not primarily concerned in the MSR depression during para-sleep, and that the postsynaptic inhibition sensitive to the subtetanic doses of the strychnine is not concerned. A possibility remains that the postsynaptic inhibition resistant to Strychnine is operative to depress the MSR during para-sleep. In addition to the MSR depression, PSR depression has been described which constituted the somatic aspect of para-sleep (I). The threshold of the motoneuron increased by 10% in ankle flexor and extensor motor units (11). However, the antidromic field potential of the motoneuron was not influenced (111). No evidence was collected to suggest the presynaptic inhibitory mechanism, that is, firstly picrotoxin did not block the MSR depression (V), secondly, the intraspinal part of the GI fibers did not show the excitability change (IV). It is concluded that in the MSR depression during para-sleep postsynaptic hyperpolarization of the motoneuron may be decisively important. P A R T 11. A U T O N O M I C A C T I V I T I E S *

Several reports have already appeared which deal with various aspects of the autonomic activities in cats during para-sleep: blood pressure fall (Candia et al., 1962; Kanzow et al., 1962), heart rate increase (Jouvet, 1961 ; Yamamoto and Kido, 1962), or decrease (Jouvet, 1961) and respiratory rate increase (Yamamoto, 1959; Jouvet, 196 1). Galvanic skin potentials, either evoked or spontaneously occurring, decreased i n both size and frequency with occasional appearance of the burst phase (Niimi et al., 1963). The pupil showed the phasic oscillatory dilatation even in the sympathetically denervated condition (Berlucchi et al., 1964). In this report, changes in the heart rate, blood pressure and respiratory rate were analyzed in intact, sympatheticotomized, or vagotomized cats. Peristaltic movements of the small intestine were also studied.

Methods Conventional electrode implantation for the EMG and EEG recordings was made. The interval of heart beats was converted into amplitude change with the interval recorder (cardiotachogram). The systemic blood pressure was recorded from the left common carotid artery. In 7 cats the cervical vagosympathetic trunks (vagal nerves -___

*

By Y . Iwamura and Y . Kidokoro.

SYC

A

B

C I

P

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Fig. 12. Polygraphic rccords in awake (A). ortho-sleep (B) and para-sleep (CI states of a cat. SMC, EEG from sensorimotor cortex; EYE., e y niovemcni; EMG. nuchal EMG ; RESP, rc,spirato:y n?ovcment: CTG, ~ardlatachogram.

A E MC

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and ascending sympathetic branches) were cut bilaterally. Observations were started one day after the operation. Stellate ganglia of both sides were removed in 3 cats. An oval-shaped abdominal window (Hukuhara, 193I ) made of transparent, thin plastic plate (70 x 40 mm), was attached to the abdominal wall, so that the small intestine could be observed. Results (1) Observations on intact chronic cats

Previous observations on changes of the heart rate, the blood pressure and the respiratory rate during transition from ortho-sleep to para-sleep were confirmed (Jouvet, 1961, 1962; Candia et al., 1962; Kanzow et al., 1962). Figs. 12 and 13 illustrate polygraphically the changes during the sleep and awake states. During orthosleep (Figs. 128 and 13B), the heart beat interval and the respiratory rhythm were regular. The former showed periodic changes associated with the latter. During parasleep (Figs. 12C and 13C) the heart rate fluctuated irregularly, either increasing or decreasing, and often accompanied the corresponding increase or decrease

A

0s

PS

30 sec

B

Fig. 14. Two types (A and B) of changes in blood pressure (BP) and cardiotachogram (CTG) during transition from ortho-sleep (0s)to para-sleep (PS). Duration of para-sleep is shown by bars in the bottom of the records.

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in the respiratory rate. Rapid eye movements and an abrupt rise in blood pressure were often seen during the accelerated phase of the heart rate. During transition from ortho-sleep to para-sleep, the blood pressure fell in 15 of 19 episodes of 7 cats. The pressure fall was associated with a heart rate deceleration (Fig. 14A). In the remaining 4 observations the blood pressure increased transiently up to 30 mm Hg (Fig. 14B), in association with tachycardia, tachypnea and rapid eye movements (Fig. 13C). Conditions under which the blood pressure showed increase instead of decrease were not encountered. Mean values of the heart rate (/min) and the respiratory rate (/min) were calculated from 36 samples of 21 cats in which ortho-sleep and the succeeding para-sleep continued, respectively, at least for 3 min, and were compared between 2 states of sleep. Change in the mean heart rate was represented as mean heart rate during para-sleep (Hp) x 100, mean heart rate during ortho-sleep (Ho) %) A

" ~

Fig. 15. A, relation between the heart rate ratio, in per cent, Hp/Ho (ordinate) and Ho (abscissa). (Explanations in the text.) Open circles (0)were obtained from intact cats, dots ( 0 )are from vagotomized cats and crosses ( x ) from sympathectomized cats. B, Relation between the respiratory rate ratio, in per cent, Rp/Ro (ordinate) and R o (abscissa), Open circles (0)are from intact cats, dots ( 0 ) from vagotomized cats, and crosses ( X ) from sympathectomized cats.

a

Fig. 17. Polygraphic records from a sympathectornized cat. An arousing stimulus k i n d clap, t) caused the change in heart rhythm in A. In para-sleep (El), a transicnt heart accelcration associated with rapid eye movcments was observed. C and D,rccords from thc samc cat as A and R, aftcr the second opcration of vagotomy. The heart ratc rcrnained almost constant throughout ortho-sleep (C) and para-slecp (D).

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and is plotted in Fig. 15A against the mean heart rate during ortho-sleep (Ho) (open circles). The ratio increased when the Ho was less than 130/min and it decreased with more than that value (r = -0.61). The mean respiratory rate was also compared from 36 para-sleep episodes of the same 21 cats. The ratio, similarly defined, mean respiratory rate during para-sleep (Rp) - ___ x 100, mean respiratory rate during ortho-sleep (Ro) is plotted by open circles in Fig. 15B against the Ro. When the Ro was less than 30/min, the ratio increased, and when Ro was more than that value, it decreased (r = -0.60). (11) Observations on vagotomized cats

N o significant change in the sleep cycle was noticed after the bilateral vagotomies. During ortho-sleep the heart rate in 7 vagotomized cats was higher than in intact cats (140-210/min). The blood pressure was also high. Respiratory fluctuation was not observed in the heart rhythm, but thghigh blood pressure persisted. The respiration was longer and deeper in the inspiratory phase. Its mean frequency during orthosleep was about half that of the intact animals (12.3/min, means of 11 episodes of 7 cats). Fig. 16, A and B illustrates the recordings during para-sleep in one of the vagotomizcd cats. In A blood pressure fluctuated with an irregular respiratory rhythm. In B, it decreased with heart rate decrease. The change in the mean heart rate of vagotomized cats is represented with dots ( 0 )in Fig. 15A, where an increase in the ratio is not revealed. Similarly in Fig. I5B,dots ( 0 )represent the change in the mean respiratory rate of vagotomized cats, which showed an increase with a somewhat smaller Ro value.

(IIT) Observations on cats without stellate ganglia In 3 cats, stellate ganglia of both sides were removed. During ortho-sleep the heart rhythm was not different from that in intact cats. Respiratory arhythmia still persisted. Acoustic stimuli which aroused the animal could induce the rate increase (Fig. 17A). The blood pressure level and both the pattern and rate of the respiration during ortho-sleep were not significantly different from those in intact cats. The heart rhythm change during the course of ortho- to para-sleep was similar to that observed in intact cats; a transient tachycardia appeared during para-sleep simultaneously with the eye movements (Fig. 17B). The mean heart rate changes in 7 para-sleep episodes were represented with crosses ( x ) in Fig. 15A. The heart rate in ortho-sleep was distributed in the range from 100 to 140/min, and during para-sleep the ratio mostly decreased slightly. The mean respiratory rate increased during para-sleep (Fig. 15B, crosses) except in two episodes where the Ro was higher than 30/min. The blood pressure fall without phases of transient rise was observed during para-sleep in 4 episodes of one cat. ( I V ) Observations on cats without both stellate ga&ia and vagaf nerve innervations I n 2 cats without stellate ganglia, cervical vagosympathetic trunks were further cut.

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253

In 12para-sleep episodes, the respiratory rate increased with an irregular rhythm. No change in the heart rate was observed during para-sleep, as illustrated in Fig. 17D. ( V ) Observations on peristalsis o f the small intestine in intact chronic cats

With the hope of finding changes of the visceral activities during the sleep cycle, the abdominal window was attached to the midst of a cat’s belly so that the intestinal movements could be seen (10 cats). The observations were made for a week or so after the operative procedures. During 1-2 h after a meal, orthodromically progressing movements of the small intestine occurred for several sec with the silent phase which continued irregularly for several tens of sec. It attenuated gradually and stopped almost completely 4-5 h after the meal. This kind of peristaltic movement did not appear to be significantly influenced during two sleep states. The results mentioned above i n sections I-IVare summarized in Table I in which arrows t, 4,+, indicate the relative increase, decrease and little change, respectively. Discussion The previous contradictory reports (Jouvet, 1961 ; Yamamoto and Kido, 1962) on the heart rate change during para-sleep seem to stem from the fact that the heart rate either decreased or increased depending on its higher or lower level during the control orthosleep. Such dual changes were also observed in the respiratory rate. However, the direction of the blood pressure change did not relate with its control value. The decelerating heart rhythm and blood pressure fall throughout para-sleep were observed in intact and vagotomized cats. It appears that these depressive changes result from depression of the central sympathetic nervous activity. Among transient increased activities during para-sleep, the abrupt heart beat increase persisted after the bilateral stellate ganglia removal through which the main sympathetic nervous supply to the heart had been blocked (Cannon et al., 1926). Further, such change disappeared after subsequent bilateral vagotomy. Thus, it is suggested that such sporadic heart beat increase results from the temporary modulation of vagal centrifugal heart control. Failure to detect changes in the intestinal movements during the sleep cycle change may be related with the fact that their movements are mainly regulated below the spinal level. PART I l l .

A R T I F I C I A L I N D U C T I O N OF P A R A - S L E E P B Y SHORT-CHAIN FATTY ACIDS

Thus far, attempts have been made to induce the paradoxical phase of sleep by utilizing the electrical stimulation within the brain (Candia et al., 1962; Jouvet, 1962). However, their results appear to be less convincing fiom the viewpoint of the reproducibility and stimulus intensity-effect relationship. On the other hand, it was reported that several short-chain fatty acids reversibly produced a state similar to physiological sleep in various experimental animals (Samson and Dahl, 1955; White and Samson, 1956; Holmqvist and Ingvar, 1957). References p . 266-268

TABLE I SUMMARY OF OBSERVATIONS ON RESPIRATION, HEART RATE A N D BLOOD PRESSURE D U R I N G PARA-SLEEP

Preparation

Respiration

Heart rate

Blood pressure

1 REM

=

( ) ?

=

= =

Relative rate during ortho-sleep Relative change in rate during para-sleep Transient acceleration associated with REM Relative rate during ortho-sleep Relative change in rate during para-sleep Transient acceleration associated with REM Relative level during ortho-sleep Relative change in level during para-sleep Transient elevation associated with REM

(1)

Intact

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+

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4 t

4 t

+

+

+

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1

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+ 1

tj.

+

control state taken as standard for comparisons. rapid eye movements. inconclusive results due to a limited number of observations. not studied.

?

J

PARA-SLEEP

255

In the present study short-chain fatty acids were given to cats with the expectation that para-sleep might follow physiological sleep (ortho-sleep). As described, this was found to be successful. Furthermore, attempts were made to investigate the participation of brain structures in the production of this chemically-induced para-sleep by comparing the effects of these drugs on intact chronic cats and acute mesencephalic, pontine or prebulbar cats. Methods Chronic experiments were carried out on intact cats (25 cats). Acute experiments were carried out in cats with a total transection of the brain stem at the precolkular (60 cats), rostropontine (14 cats) or rttropontine (I2 cats) level and in cats with anterior cerebellectomy and bilateral gasserectomies ( I 2 cats). In the intact chronic cat, bipolar EEG electrodes were implanted in the neocortex, amygdala and hippocampus, and the EMG was recorded bipolarly from the neck muscles. In acute preparations the EEG was recorded from the neocortex and hippocampus. The EMG of the neck muscles, extensor, and flexor muscles of the elbow and knee joints were recorded with bipolar electrodes. Ocular movements, heart rate and respiratory movements were also recorded with conventional techniques. Short-chain fatty acids (1.0 molar solution) were buffered at pH 7.4--7.6 with sodium hydroxide. The fatty acids were injected into the cephalic or saphenous vein, and vertebral, lingual or common carotid artery through a polyethylene tube.

Results ( I ) Chroriic observation* Intravenous injection of the sodium n-butyrate solution into the intact chronic cat induced the sleep state both electrographically and behaviorally. Fig. 18 shows an example of the sequential changes of polygraphic recordings after the injection (1.5 mmole/kg). Fig. 18A represents the control state before the administration, when the animal was behaviorally awake. One minute after the injection (B), the neocortical EEG showed the pattern of the slow wave with spindle bursts, and spike activity appeared in the hippocampus and amygdala. Three min later ( C ) , while the cat was behaviorally silent, the EEG changed into the low voltage fast activity, and the tonic discharges of the neck muscle disappeared completely. The appearance of rapid eye movements and increases in the heart and respiratory rates were observed. Polygraphically these changes in C could not be distinguished from those which characterized the spontaneously occurring para-sleep. Four to 15 min afterwards, the animal returned to the ortho-sleep state. By extraneous stimuli such as noise, the animal could be awakened from this state as easily as from the spontaneous para-sleep. The para-sleep state was observed in every trial of repeated injections of the same amount (1.5 mmole/kg), as seen in Fig. 19. n-Butyrate was injected 7 times at inter-

*

By M. Matsuzaki and H. Takagi.

References p.1266-268

256

T. T O K I Z A N E

LAMY

Fig. 18. Sodium n-butyrate in the intact chronic cat. Polygraphic records in the awake state (A), 1 min after intravenous injection of sodium n-butyrate (1.5 mmolejkg) (B) and 3 min later (C). Records in each, from top to bottom, EEGs of amygdala (AMY), hippocampus (HIP), anterior sigmoid gyrus (ANT. SIG), lateral gyrus (LAT), electromyographic activity of neck muscle (EMG), respiratory movement (RESP), eye movement (EM) and electrocardiogram (EKG). L and R indicate left and right sides, respectively.

vals of about one hour. A slow wave pattern appeared in the neocortical EEG 1-7 min after the injection, lasted for 1-2 min, and was followed by the para-sleep phase for 7-10 min. In the untreated control condition of this cat immediately before the drug administration, the spontaneous para-sleep occurred at intervals of 2-2.5 h and continued for 6-10 min. With smaller doses (0.5-1 .O mmole/kg) the para-sleep rarely appeared, and only the slow wave phase continued for less than 15 min and recovered to the control awake state. When larger doses (4-5 mmole/kg) were administered, the para-sleep

257

PARA-SLEEP

did not appear. Ortho-sleep was induced thereafter over 40-60 min and occasionally followed by the para-sleep which could endure only for 0.5-2 min. Thus, in intact chronic cats an appropriate amount of sodium n-butyrate appears to induce para-sleep only after ortho-sleep. Various short-chain fatty acids were injected intravenously, and their effective doses were determined which reproducibly induced para-sleep in the intact cat: sodium n-butyrate (1 -3 mmole/kg), sodium isobutyrate (1-3 mmole/kg), sodium isovalerate (1-2 mmole/kg), sodium n-caproate (0.3-0.5 mmole/kg), sodium y-hydroxybutyrate (0.5-1.5 mmole/kg) (Jouvet et al., 1961) sodium y-butyrolactone (0.5-1.5 mmole/kg) (Jouvet et al., 1961) and sodium a-hydroxyisobutyrate (1-1.5 mmole/kgl On the other hand, sodium propionate (1-2 mmole/kg), sodium acetoacetate (1 mmole/kg) and sodium fl-hydroxybutyrate (1-1.5 mmole/kg) did not produce the para-sleep state. ( I l ) Eflect of sodium n-butyrate on acute preparations ( i ) Mesencephaliccats". The brain stem was transected at a level between the rostra1 border of the superior colliculus and the caudal end of the mammillary bodies under ether anesthesia. The recording was started at least 2 h after the end of ether insufflation. In this preparation, the tonic electromyographic activity of neck muscles was sustained with little fluctuation for 6-8 h. As shown in Fig. 20, the tonic neck muscle activity was almost completely abolished 1.5 min after the intravenous injection of n-butyrate (1.5 mmole/kg). The tendency of gradual decrease was already noted 30 sec after the end of the injection. The silence of the neck muscles continued for 1.5-3 min. The rapid eye movements, characteristic of para-sleep in the intact cat, were also observed, although not so markedly as in the intact cat. Simultaneously the slowing 50

rnin

Fig. 19. Diagrammatic representation of sleep states of the intact chronic cat when sodium n-butyrate (1.5 mniole/kg) was given intravenousiy at intervals of about 1 hour. Awake state, ortho-sleep and para-sleep are represented as insert at bottom right indicates. The black line at the left corner of each row shows the period of injection. -~ ~~~

*

By M. Matsuzaki and H. Takagi.

Ref<,rences p. 266-268

258

T. T O K I Z A N E

I

I Sec Fig. 20. Sodium n-butyrate in the acute mesencephalic cat. The upper left is the cordrol state, and records 1 inin after the injection (I .5 mmole/kg) are shown in upper right. Polygraphicrecordings of neck EMG (EMG), eye movements, respiration (RESP) and EKG. The state after 7 min is illustrated in the lower record. The burst activity at upper right is the jerky movement of facial and auricular muscles.

of respiration and the acceleration of the heart rate were observed. Those effects were confirmed in 36 out of 51 trials (70%) (1.5-2.0 mmole/kg). As in the intact chronic cats, the minimal effective dose of n-butyrate to abolish the tonic activity of the neck muscles in mesencephalic cats was about 1.5 mmole/kg. When 1.5 mmole/kg was applied repeatedly at intervals of more than 40 min, the neck muscle always became silent with a latency of 1-4 min after each injection. And this lasted for 4-15 min. Various fatty acids used in the chronic state were applied to mesencephalic cats and same results were confirmed. (ii) Pontine cats". The transection of the brain stem was performed at the level between the caudal border of the superior colliculi and the rostral border of the pons (pontine cat). Neck muscle activity was sustained in this preparation. It was completely abolished 0.5-2.5 min after the intravenous injection of n-butyrate (1.5 mmole/ kg) (Fig. 21). An irregularity of respiratory movement was usually observed (B), which was associated with the slowing or acceleration of the heart rate. Eye movements were rarely noticed. As for control EEG of the brain rostral to the transection, regular slow waves were observed in the hippocampus, and low voltage fast waves with interspersed spindle bursts were observed in the neocortex, as shown in A. After n-butyrate administration, the hippocampal regular slow waves gradually disappeared, and spike activity was observed during the neck muscle silence (C). In the neocortical EEG, the interspindle phase became shorter, and low amplitude slow waves appeared. These changes in the EEG outlasted the muscle silence. They continued for 5-10 min and persisted even though the neck muscle activity returned to the control value (E).

*

By N. Mano, Y . Nakamura and H. Yanagida.

PARA-SLEEP

259

On injection of a smaller dose (0.5 mmole/kg), similar EEG changes were observed, but the decrease of tonic neck muscle activity was absent. (iii) Prebulbar cats". After anterior cerebellectomy, the brain stem was transected

Fig. 21. Sodium n-butyrate in the acute pontine cat. A is the control state before the administration At the arrow intravenous injection of sodium n-butyrate (1.5 mmole/kg) was started, ending 10 sec later. B, C , D, E and F a r e polygraphic records obtained at 1.5,4,6, 14 and 21 min after the injection. ELBOW EXT, EMG of elbow extensor.

*

By N. Mano, Y. Nakamura and H. Yanagida.

R r j i r m c r s p . 266-2611

260

T. T O K I Z A N E

at the level between 9-10 mm caudal to the caudal end of the inferior colliculi and the caudal border of the pons (prebulbar cat). In this preparation, the elbow and knee joints were kept flexed. Within 2-3 h after the transection, vomiting behavior was often observed, which later disappeared. The neck muscle activity remained almost constant. Artificial ventilation was necessary, as spontaneous respiration never returned after the transection. Intravenous injection of n-butyrate (1.5 mmole/kg) was rarely effective on the tonic neck muscle activity, as shown in Fig. 22. With a further dose of 2-3 mmole/kg, the

26 1

PARA-SLEEP A

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.

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.

.

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C

D

1

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ISEC

Fig. 22. Sodium n-butyrate effect on the EMG in the acute prebulbar cat. A, control state. Sodium n-butyrate (1.5 mmole/kg) was injected intravenously starting at the arrow and lasting for 20 sec. B, C and D, records respectively at 1, 5 and 9 min after the injection. Each record consists of the electromyogram of the posterior neck muscles (upper) and of the left elbow flexor (lower).

tonic neck muscle activity decreased moderately but was not completely abolished, although flexor rigidity was decreased or abolished completely. The low voltage fast activity with rare occurrence of spindle bursts in the neocortex and continuous regular slow waves in the hippocampus continued in the untreated condition. One to 2 min after the injection (1.5-2 mmole/kg) the spindle bursts increased in numbers, slow waves appeared in the neocortical EEG and the hippocampal slow waves disappeared. With 3-4 mmole/kg, the slow waves and spindle bursts in the neocortex were replaced gradually within 3 min by low voltage fast waves with spike activity. This spike activity appeared most frequently during 4-10 min after the injection, then decreased gradually in number to vanish completely after 15-25 min after the injection (Fig. 23, B and C). These EEG changes were also observed in this preparation after immobilization by Flaxedil. References p . 266-268

262

T. T O K I Z A N F A L.ANTSIG

-

L ANT SIG I YP 1

~ - -I

-

200YV

ISEC

Fig. 23. Sodium n-butyrate in the acute prebulbar cat. A , control EEG pattern. B and C illustrate the spike activity 7 min after intravenous injection of sodium n-butyrate (3 mmole/kg). In D, the EEG returned to the control pattern after 30 min. Time scale at the bottom right applies to A, B and D; in C the paper running speed is 3 times faster. (MP) indicates monopolar recording, negative deflection upwards. The reference electrode was on the median point of the frontal bones.

Anterior c e r e b e l l e ~ t o ~ i i z e It ~ ~is~known t ‘ ~ . that in the cat the blood is supplied to the lower brain stem by the hasilar artery and to the upper brain structures by the common carotid artery (Chungcharoen et a/., 1952; Holmes et a/., 1958). The drug effect was compared among venous, vertebral and common carotid injections in cats after anterior cerebellectomy and bilateral crushing of the trigeminal nerves. The neocortical EEG was characterized by low voltage fast activity with sporadic spindle bursts and without slow waves. The neck muscle showed a sustained activity. After an intravenous injection of n-butyrate ( I .5-2 mmole/kg) the tonic neck muscle activity disappeared within 1-3 min (9 out of 14 trials). I n the neocortical EEG, spindle bursts disappeared, and hippocampal slow waves became regular. Irregular respiratory movements and arhythmia were usually observed. Rapideye movements were also seen, though not so conspicuously as in the intact cat. This phase, polygraphically identical to para-sleep, returned to the control state after 3-7 min. With a smaller dose (0.5 mmole/kg) only the EEG changed; slow waves appeared with increased appearance of spindle bursts. (it,)

*

By N. Mano, Y. Nakamura and H. Yanagida.

263

PARA-SLEEP

With the injection of n-butyrate (0.1-0.4 mmoleikg) into the vertebral artery (21 trials), the tonic neck muscle activity was markedly decreased or abolished in 14 out of 21 trials (Fig. 24). Sodium n-butyrate was diluted with distilled water to bring the osmotic pressure to that of the body fluid (300-350 mosm/l). The pH was 5.2-7.0. Injection was performed at the rate of 0.02-0.04 ml/sec. In several trials the decrease in the neck activity started as early as 2-3 sec after the start of the injection, and its complete abolition was attained within 10 sec. When neck muscles were silent, the neocortical EEG showed a slow wave pattern (4 cats) or changed into low voltage fast waves (3 cats). In thesecats irregular respiration, arhythmia and rapid eye movements were also observed. The latency of these polygraphic changes was usually 2-3 min after the injection. Thus, polygraphically the induced state was similar to the spontaneous para-sleep of the intact chronic cat. lntralingual or intracarotid injection (0.2-0.4 mmole/kg) induced a completely different state. Spindle bursts and slow waves appeared in the neocortical EEG, but the low voltage fast activity was never observed. The tonic neck muscle activity increased in 9 trials except one in which it was abolished. Sodium n-butyrate solution (I .O molar, pH 7.4-7.6) used in these experiments contained about 2.3 "/, (w/v) of sodium. This corresponds to the equivalent volume of 6 % (w/v) solution of sodium chloride. Known as Setchenow's inhibition (Setchenow, 1863) or Richet's inhibition (Richet, 1883; Ozorio de Almeida et nl., 1938) in the frog, sodium chloride has some afinity with the brain stem and can depress spinal reflex activity. Therefore, if sodium plays some role in this type of inhibition, it may

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-

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Fig. 24. Effect of intravertebral injection of sodium n-butyrate (0.4 mmole/kg) in the acute anterior cerebellectomized cat. A , control in which the arrow indicates the starting of the injection performed at a constant speed for 30 sec. 9, C, D, E and F, records taken I , 2, 3.5, 8 and 1 1 min after the start of the injection. RcfiJwnces p . 266-266

264

T. T O K I Z A N E

happen that we erroneously attribute the sodium effect to butyrate. In the acute preparations described above changes were not produced with intravenous injection of sodium chloride solution. When 6% saline was injected into the vertebral artery, the neck EMG increased abruptly 2-4 sec after the beginning of injection, accompanied by irregular heart rate and respiration. When 0.9 % (w/v) saline was used intraarterially, no effect was observed on the activities of the somatic and autonomic effectors mentioned above. Thus the probable participation of sodium ions in the para-sleep induction was eliminated. COMMENTS

In agreement with previous reports (White and Samson, 1956; Holmqvist and Ingvar, I957), intravenous injection of sodium n-butyrate and certain related substances induced various changes which characterize ortho-sleep, such as slow waves with spindle bursts in the neocortical EEG, disappearance of theta waves and appearance of spike activity in the hippocampal EEG, regular and slowed respiration and heart rate, and relatively slight activity of the neck muscle. Further, when a moderate amount of n-butyrate was used, this phase was invariably followed by a state which was in no way distinguishable polygraphically from the spontaneously occurring para-sleep. In acute mesencephalic and pontine cats, neck muscle silence, irregular respiration and heart rate were also observed with the same dose of n-butyrate as in the intact chronic cat. Rapid eye movements during neck muscle silence were observed in the mesencephalic cats, but not in the pontine cats except one cat. As a possible cause, it is probable that the oculomotor nucleus or nerves were concomitantly damaged during the transection of the brain stem. Slow waves and spindle bursts appeared in the neocortical EEG of the isolated brain which had been transected at the precollicular or rostropontine level, but they were never followed by low voltage fast waves. Hence, it may be that in these two acute preparations n-butyrate can induce a state polygraphically similar to para-sleep except for EEG of the isolated brain. These EEG effects show that n-butyrate is incapable of inducing the para-sleep pattern if the brain below the pons were removed. Contrary to the results with the mesencephalic or rostropontine cat the tonic activity of neck muscles in the acute prebulbar cat was little affected by 1.5 mmole/kg of n-butyrate. With 4 mmole/kg, the tonic neck muscle activity decreased, and it was not complete. This indicates that n-butyrate influences structures below the transection, namely the medulla oblongata and the spinal cord, resulting in the depression of muscle activity. Incidentally, spinal mono- and polysynaptic reflexes were reduced in magnitude in the acute state with lower thoracic transection of the spinal cord. After n-butyrate injection (0.5-2.0 mmole/kg) their magnitude of peroneal and tibia1 MSRs evoked by sciatic nerve stimulation gradually decreased to a minimal value 1.5-6 min after the injection. This time course shows close similarity to that of the change in tonic neck muscle activity in the acute mesencephalic, pontine or chronic intact cat. The decrease started within 1 min after the injection (Kidokoro and Kubota’s obser-

PARA-SLEEP

265

vation). Hence, the possibility cannot be neglected that the depressive action of nbutyrate to the spinal cord contributes to the inducement of para-sleep. It remains to be found what kind of butyrate effects are due solely to changes occurring in the brain stem. Intra-arterial injection of n-butyrate throws light on the primary important role of the lower brain stem in producing para-sleep by this drug. In acute anterior cerebellectomized cats, polygraphic changes identical with those in intact chronic cats were obtained after the intravenous as well as intra-arterial injections. Para-sleep was produced by the injection into the vertebral artery of less than0.5 mmole/kg. The tonic, neck muscle activity began to decrease as early as 2-3 sec after the beginning of injection. A dose as small as 0.1 mmole/kg was effective in abolishing the neck activity, which was about one-fifth of the minimal dose effective on the mono- and polysynaptic reflexes of the spinal cat. Intralingual or intracarotid injection of the same dose of n-butyrate failed to evoke these changes. From these observations it is concluded that the para-sleep pattern is produced by the action of sodium n-butyrate in the acute cats probably acting on the lower brainstem structure. SUMMARY

What are the essential activities of para-sleep? How should para-sleep be characterized? From polygraphic analyses of the cat it is shown that both autonomic and somatic activities were generally suppressed, although there were occasionally increased activities in various effector organs. In the former both sympathetic and para-sympathetic activities were depressed. The para-sleep state of these activities persisted after decortication or even in the pontine cat, and furthermore, in early stages of the ontogenesis of human beings, as well as in cats, or in premature infants in which the neocortex was underdeveloped, typical somatic and autonomic activities of para-sleep have been observed (Roffwarg et al., 1964; Valtax et al., 1964). Therefore, the activated pattern of the EEG during this sleep does not constitute its essential part. In other words, para-sleep can be regarded as the sleep of somatic and autonomic activities, and the EEG pattern may be considered as secondary. In this connection one may recall the terms used by C . von Economo who differentiated ‘Hirnschlaf’ from ‘Korperschlaf‘ (von Economo, 1929). If it is permitted to borrow these terms, ortho-sleep may correspond to brain-sleep and para-sleep is that of the body (body-sleep). As for structures taking part in the production of para-sleep, probably the pons is responsible for the rhythmic alterations of sleep and wakefulness of the body. It must be noted that the pons may be endowed with a mechanism not only to induce para-sleep, but also to inhibit it, just as the brain stem has respiratory centers of dual nature, i.e., inspiratory and expiratory. Other structures such as the hypothalamus may have some relation with the pontine rhythm. From analyses of the EEG activities I have speculated (Tokizane et al., 1962; Tokizane, 1963), as illustrated in Fig. 25A, that the neocortex receives controlling impulses tonically from the hypothalamus and phasically from the midbrain reticular References p.-266-268

266

I. T O K I Z A N E

A

Fig. 25. A, schematic representation of the ascending controlling mechanism of cortical activity. B, schematic representation of the possible interactions between the pons and the hypothalamus which produce the 'rhythm' of para-sleep.

formation, while the limbic cortices are controlled solely by the hypothalamus. Impulses from the hypothalamus to the neocortex ascend two pathways. One goes down to the midbrain reticular formation and combines with impulses from their sources, constituting the diffuse projection system via thalamic non-specific nuclei.The other is the pathway which ascends directly to the specific thalamic nuclei and projects to specific projection areas of the neocortex. Therefore, the rhythm of sleep and wakefulness of the neocortex can be modulated by the hypothalamic activity which is not only neurally controlled by the lower brain but also humorally controlled. This hypothalamic activity will interfere with the above-discussed pontine activity and then the complex rhythm of sleep may be formulated. These considerations are included schematically in Fig. 25B in which hypothalamic and pontine interrelations are illustrated. Interactions between hypothalamic and pontine structures for the sleep cycle formation are to be studied. REFERENCES BERLUCCHI, G . , MORUZZI,G., SALVI,G., AND STRATA,P., (1964); Pupil behavior and ocular movements during synchronized and desynchronized sleep. Arch. ital. Biol., 102, 230-244. CANDIA, O., FAVALE, E., GIUSSANI, A,, AND Rossr, F., (1962); Blood pressure during natural sleep and during sleep induced by electrical stimulation of the brain stem reticular formation. Arch. ital. Biol., 100,216-233. CANNON, W. B., LEWIS,J. T., A N D BRITTON, S. W., (1926); Studies on the conditions of activity in endocrine glands. XVIl. A lasting preparation of the denervated heart for detecting internal secretion, with evidence for accessory accelerator fibers from the thoracic sympathetic chain. Amer. J . Physiol., 11,326-352.

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CHUNGCHAROEN, D., DALY,M. DE B., NEIL,E., AND SCHWEITZER, A., (1952); Theeffectof carotid occlusion upon the intrasinusal pressure with special reference to vascular communications between the carotid and vertebral circulations in the dog, cat and rabbit. J . Physiul. (Lona‘.), 117, 56-76. ECCLES,J . C., (1957); The Physiology of Nerve Cells. Baltimore, Johns Hopkins Press. ECCLES,J. C., (1964); The Ph.vsio/ogy of S.vnrrpses. Berlin, Springer-Verlag. ECCLES,J. c.,MAGNI, F., A N D WrLLrs W. D., (1962); Depolarization of central terminals of Group I afferent fibers from muscle. J . Physiol. (Loncf.), 160, 62-93. ECCLES,J . C., SCHMIDT, R. F., AND WILLIS,W. D., (1963a); Pharmacological studies on presynaptic inhibition. J . Physiol. (Lond.), 168, 500-530. ECCLES,J. C., SCHMIDT, R . F., AND WILLIS,W. D., (1963b); The location and the mode of action of the presynaptic inhibitory pathway on to Group I afferent fibers from muscle. J. Neurophysiol., 26,506-522. GASSEL, M. M., MARCHIAFAVA, P. L., AND POMPtlANO, o., (1964); Tonic and phasic inhibition of spinal reflexes during deep, desynchronized sleep in unrestrained cats. Arch. ital. Biol., 102,471-499. GIAQUINTO, S., POMPEIANO, O., AND SOMOGYI, I., (1964); Descending inhibitory influences on spinal reflexes during natural sleep. Arch. ital. Biol., 102, 282-307. GIAQUINTO, S., POMPEIANO, O., A N D SOMOCYI, I., (1964); Supraspinal modulation of heteronymous monosynaptic and of polysynaptic reflexes during natural sleep and wakefulness. Arch. ital. Biol., 102,245-281. HOLMES, R. L., NEWMAN,P. P., A N D WOLSTENCROFT, J. H., (1958); The distribution of carotid and vertebral blood in the brain of the cat. J . Physiol. (Lond.), 140, 236-246. HOLMQVIST, B., A N D INGVAR, D. H., (1957); Effect of short chain fatty acid anions upon cortical blood flow and EEG in cats. Experientia (Basel), 13, 331-333. HUKUHARA, T., (1931); Die normale Dunndarmbewegung (mit Hilfe der Bauchfenstermethode und Kinematographie). Pfliigers Arch. ges. Physiol., 226, 5 18-542. JOUVET, M., (1961); Telencephalic and rhombencephalic sleep in the cat. The Nature of Sleep. Ciba Foundation Symposium. London, Churchill. JOUVET,M., (1962); Recherches sur les structures nerveuses et les mecanismes responsables des differents phases du sonimeil physiologique. Arch. i t d . Biol., 100, 125-206. JOUVET,M., CIER,A., MOUNIER,D., A N D VALTAX, J.-L., (1961); Effets d u 4-butyrolactone et du 4-hydroxybutyrate de sodium sur I’EEG et le comportement du chat. C. R. Sac. Biol. (Paris), 155, 1313-1316. KANZOW,E., KRAUSE, D., A N D KUHNEL, H., (1962); Die Vasomotorik der Hirnrinde in den Phasen desynchronisierter EEG Aktivitat im naturlichen Schlaf der Katze. Pfliigers Arch. ges. PhyJiol., 274, 593-607. KAWAI,I., AND SASAKI, K., (1964); Effects of Strychnine upon supraspinal inhibition. Jap. J . Physiol., 14, 309-317. KUHOTA, K., TWAMURA, Y . , AND N I I M IY., , (1965); Monosynaptic reflex and natural sleep in the cat. J. Neurophysiol., 28, 125-1 38. DENO, R., (I 935); The synaptic delay of the motoneurones. Amer. J . Physiol., 111, 272-282. LORENTE T., (1964); Paradoxical phase of sleep: its artificial MATSUZAKT, M., TAKAGI,H., A N D TOKIZANE, induction in the cat by sodium butyrate. Science, 146 (No. 3649), 1328. K., AND TWAMURA, Y . ,(1963); GSRs and PSRs in the so-calledparadoxical sleep NIIMI, Y . , KUBOTA, state. Proceedings of the XIlth annual meeting of the Japan EEG society. No. 113, p. 216. OZORIODE ALMETDA, M., MOUSSATCH~, H., AND VIANNA DIAS,M., (1938); Recherches sur I’inhibition de Ch. Richet. Arch. int. Physiol., 47, 277-288. O., A N D SWETT,J. E., (1962a); EEG and behavioral manifestations of sleep induced by POMPEIANO, cutaneous nerve stimulation in normal cats. Arch. ital. Biol., 100, 31 1-342. POMPEIANO, O., A N D SWETT,J. E., (1962b); Identification of cutaneous and muscular afferent fibers producing EEG synchronization of arousal in normal cats. Arch. ital. Biol., 100, 343-380. PORTER, R., (1963); Focal stimulation of hypoglossal neurones in the cat. J . Physiol. (Lond.), 169, 6 30-640. RENSHAW, B., (1940); Activity in the simplest spinal reflex pathways. J . Neurophysiol., 3, 373-387. RICHET,C., (I 883); Deux experiences d’inhibition sur la grenouille, et quelques autres faits relatifs a I’inhibition. C. R. Soc. Biol. (Paris), 7S4, 456-459. ROFFWARG, H. P., DEMENT, W. C . , AND FISHER, C., (1964); Preliminary observations of the sleepdream pattern in neonates, infants, children and adults. Problems of Sleep and Dream in Children. New York, Pergamon Press.

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SAMSON, F. E., JR., AND DAHL,N., (1955); Coma produced by injection of short chain fatty acids. Fed. Proc., 14,29. SETCHENOW, J., (1 863); Physiologische Studien uber die Hetnrrtungsmechanismenfur die Reflextatigkeit cles Riickenmarks irn Gehirne des Frosches. Berlin, Verlag von August Hirchwald. SHIMAMURA, M., AND LIVINGSTON, R. B., (1963); Longitudinal conduction systems serving spinal and brain-stem coordination. J . Neurophysiol., 26, 258-272. TOKIZANE, T., (1963); Hypothalamic control of cortical activity and some observations during different stages of sleep. International Symposium on the anatomical andphysiological basis of sleep, Lyon, September 9-11, 1963. TOKIZANE, T., HIRAO,T., TORII,S., KAWAMURA, H., AND NAKAMURA, Y., (1962); Hypothalamic activating mechanism for limbic and neo-cortices. Excerpfa wed. (Amst.), Int. Congr. Ser. No, 48, Abstract no. 11 32. VALTAX, J. L., JOUVET, D., AND JOUVET, M., (1964); Evolution klectroencephalographique des diffkrents etats de sommeil chez le chaton. Electroenceph. elin. Neurophysiol., 17, 21 8-233. VON ECONOMO, C., (1929); Schlaftheorie. Ergebn. Physiol., 28, 312-339. WALL,P. D., (1958); Excitability changes in afferent fibre terminations and their relation to slow potentials. J . Physiol. (Lond.), 142, 1-21. WHITE,R. P., AND SAMSON, F. E., JR.,(1956); Effects of fatty acid anions on electroencephalograms of unanesthetized rabbits. Amer. J . Physiol., 186, 271-274. YAMAMOTO, K., (1959); Studies on the normal EEG of the cat (in Japanese). A . R . Shionogi Res. Lab., 9,1126-1164. YAMAMOTO, K., AND KIDO, R., (1962); Ncurophysiology of sleep (in Japanese). Clinical Psychiatry (Seishin Igaku), 4, 821-830.

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Clinical and Epidemiological Studies on H epatocerebral Disease in Japan MASAKT YOSHTKAWA, T O S H I J l M O Z A I *

AND

SHUNSAKU HIRAI

Department of Geriatrics, Faculty of Medicine, University of Tokyo, Tokyo (Japan)

Hepatocerebral disease is the general term to describe the clinical syndrome in which both the brain and the liver are involved with a causal relationship between the two. A considerable number of histopathological studies on this disease had been reported in Japan before 1940. After World War 11, however, a truly amazing progress has been made concerning this disorder, represented by studies on copper metabolism in hepatolenticular degeneration (H.L.D.) and ammonia toxicity in portal systemic encephalopathy. In I96 I , Prof. Okinaka lectured at the 7th International Congress of Neurology under the title of ‘Neurological Disorders associated with Diseases of the Liver’. In this lecture, he classified this syndrome into two categories, namely, H.L.D. and hepatic encephalopathy, and reported on the clinical statistics of H.L.D. in Japan, histochemical studies of copper, the resemblance in copper metabolism between the fetus and patients with H.L.D., portal systemic encephalopathy due to chronic shistosomiasis japonica and others. This review will be divided into two chapters: H.L.D. and hepatic encephalopathy. H EP A TO L E N T I C U L A R D E G ENE R A TI 0 N

H.L.D. had been considered to be rare in Japan until the discovery of the abnormalities in copper metabolism attracted a large number of clinical investigators to the study of this disease with the aid of modern laboratory techniques, resulting in the frequent appearance of case reports in Japan in recent years. ( A ) Incidence and clinical features

According to Okinaka (Okinaka, 1961 ; Okinaka et al., 1961), 62 cases of H.L.D., except for fallacious cases, were reported in the Japanese literature during the 10-year period 1949 to 1959. Age and sex The ages and sexes of these cases are shown in Fig. 1. The oldest patient was 55

*

Department of Internal Medicine, Faculty of Medicine, University of Tokyo, Tokyo, Japan.

References p . 283-284

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n 11-15 16-2021-25 26-30 31-4341-50 50 Age

in

Years

Fig. 1. Distribution of age of onset and sex in patients with Wilson’s disease in Japan.

years and the youngest 5 years and 5 months old. Thirty-two (51.6%) out of 62 were between the age of 1 1 and 20, and 93.5 % fell in the range of 5 to 30. Forty-one (66.2 %) were males and 21 were females, giving a male to female ratio of 2 to I . Among 43 families investigated from the hereditary viewpoint, familial occurrence and consanguineous marriage were found in I5 families (35 ”/,). Most of the consanguineous marriages were between cousins. According to Arima (Arima et al., 1963b), the frequency of consanguineous marriages in 31 families i n which abnormalities of copper metabolism were confirmed were as follows: marriage between cousins, 40.3 %; secondary cousins, 6.5 %; other consanguineous marriages, 3.9 ”/,; and no consanguineous marriage, 49.3 %. Initial symptoms When initial symptoms were classified into ( I ) neurological, (2) abdominal, o r (3) mental or personality changes, 71 % started with neurological symptoms, 23 % with abdominal symptoms and 6 % with mental or personality changes. However, a s will be described later, Arima pointed out the predominance of abdominal symptoms in pediatric patients especially those under the age of 9 years. Among early neurological symptoms, tremor, rigidity and dysarthria were most frequent, being observed in about 80% of all cases. Choreiform or athetoid movements and dysphagia were observed in about 30%, whereas apparent ataxia was found in none. Other neurological signs included : exaggerated deep tendon reflexes (32 %), pathological reflexes (I 3 %), epileptic seizures ( 1 6 %) and others. Among abdominal symptoms, ascites was seen in 6 cases, and in 26 cases (84% of those tested) definite disturbance of liver function was demonstrated. Kayser-Fleischer corneal ring, the specificity and diagnostic value of which are well recognized, was found in 48 (86%) of 56 cases.

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Fig. 2. Copper granules in Kayser-Fleischer ring. Oil-immersion. Rhodanine-hematoxylin stain.

( B ) Copper metabolism As is well known, Harowitz (1930) and Cummings (1948) first observed an increased copper content in the liver and brain of patients with H.L.D., and great contributions have been made in the problem of urine and serum copper and its relationship with ceruloplasmin by Denny-Brown and Porter (1951), Bearn and Kunkel (1954) and Cartwright et a/. (1 954). Our experience (Okinaka, 1961; Okinaka ef a/., 1961; Mozai, 1953; Watanabe, 1960) with Japanese patients also definitely corroborated the presence of a disturbance in copper metabolism in this disease. Furthermore, in 1954, Okinaka et al. demonstrated for the first time abnormal depositions of copper granules in the livers of patients with H.L.D. histochemically, an observation which later received a world-wide confirmation. The demonstration of copper granules in the pigment of the KayserFleischer corneal ring has also been achieved histochemically by Mozai (Fig. 2). These findings have led to great progress in our knowledge of this disease, strengthening our ability to make a correct diagnosis. Many workers are now ofthe opinion that H .L.D. should always be ruled out in the absence of abnormal copper metabolism. On the other hand, with the aid of biochemical findings, more and more cases of atypical H.L.D. according to the classical diagnostic criteria have appeared in recent years Rrfrrentes p. 283-264

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(Mozai et al., 1962). According to Arima (Arima et al., 1963a) who pointed out the difficulty in establishing the diagnosis of H.L.D. in children without biochemical methods, H.L.D. occupied almost half the autopsied cases above the age of 3 years who died from liver diseases at the Department of Pediatrics, University of Tokyo during the 5-year period between 1956 and 1961. The first diagnoses of these cases were acute hepatitis, acute yellow atrophy of the liver, chronic hepatitis, Banti’s syndrome ( 2 cases of each) and liver cirrhosis (5 cases), only 4 cases being diagnosed correctly on the basis of the typical neurological symptoms such as dysphagia, rigidity or tremor. This report suggests the importance of hepatic symptoms in juvenile cases of H.L.D. According to Mozai, on the other hand, no hypoceruloplasminemia was detected among patients with liver diseases except for those who were diagnosed as H.L.D. from clinical features.

Copper metabolism in human fetus (Okinaka, 1961) In view of the frequent familial occurrence and relative preponderance of H.L.D. in the younger age groups, as well as the close relationship of abnormal copper metabolism to the etiology of the disease, we have conducted investigations on the metabolism of copper in the human fetus. According to results with our histochemical method, copper deposition in the liver gradually increased in the fetus from about the 5th month of pregnancy, reached a maximum in the 6-7th month, and gradually decreased thereafter. Moreover, as shown in Fig. 3, ceruloplasmin was definitely low in the umbilical blood, while the maternal venous blood showed a very high level. Simultaneous determinations of serum copper in maternal blood and umbilical venous blood in 10 cases upon delivery, however, showed equally high values in both. A high

0.75 0.70 0 60 0 55

050 0.45 040 0 35

0.15 0 10 0 05

Fig. 3. Serum ceruloplasmin concentration in various conditions, determined as p-phenylenediamine oxidase activity by modified Ravin’s method (O.D. unit).

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non-ceruloplasmin copper level in the fetus, therefore, is strongly suggested. Copper metabolism in the fetus thus closely resembles H.L.D. The abnormal copper metabolism of the fetus disappears physiologically within a short time after delivery. If there were persistence of such a state due to some metabolic error, it would be conceivable that excessive copper deposition might continue in the liver or brain and eventually cause pathological changes in these organs. This might represent one of the keys towards understanding the etiology and pathogenesis of H.L.D. Histochemiral demonstration of copper As mentioned before, we (Okinaka et a/., 1954) demonstrated copper granules in the liver and brain of H.L.D. histochemically for the first time. The deposition of copper granules in this disease indicated a specific distribution. In the liver, some lobules had abundant intraprotoplasmic copper granules, while other lobules contained no demonstrable copper granules (Fig. 4). Scarcely any copper granules were demonstrated in the Kupffer cells. Although some copper granules were

Fig. 4. Typical distribution of histochemically demonstrable copper granules in the liver in Wilson’s disease. The pseudolobule in the central portion of the photograph is composed of liver cells filled with copper granules. In the surrounding lobules, copper granules are scarce. x 10. Rhodaninehematoxylin stain. References p . 283-284

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occasionally seen in cases of cirrhosis and acute yellow atrophy of the liver they were not only much smaller in quantity, but also showed a different distribution. These findings suggest morphological and biochemical characteristics of the liver in H.L.D. As for the morphological changes in the liver in H . L . D . , Shikata (1960) investigated in detail the livers of 9 autopsy cases of H.L.D., including asymptomatic cases with hypoceruloplasminemia. According to his studies, the early changes consist of diffuse degeneration of liver cells with slight proliferation of the connective tissue. These early changes were followed by massive fatty metamorphosis and collapse of the liver cells with marked proliferation of the connective tissue. At this second stage, clinical manifestations such as jaundice, ascites, splenomegaly, and disturbance of liver function frequently became manifest, occasionally leading to death (so called ‘abdominal Wilson’). When the patient was able to survive this state, or the progress of the disease was more gradual from the beginning, the liver showed a structure consisting of both degenerating and regenerating liver cells, until the final picture of coarse nodular atrophic cirrhosis was reached. From our histochemical investigations th e distribution of copper granules in these 3 stages is as follows. In the first stage, co,pper granules are uniformly distributed in all lobules, while in the second stage they can be demonstrated only in those liver cells with minimal morphological changes. In the last stage, these granules indicate the specific distribution as mentioned above. These morphological as well as histochemical findings suggest the disappearance of copper granules observed in the first stage upon necrosis of the liver cells in the second stage, and the presence of copper granules only in the surviving liver cells surrounded by regenerated liver cells without histochemically positive copper. Such histochemically positive copper, called ‘direct reacting copper’ by Mozai, was shown to have SHlinkages with protein according to his histochemical method. In the brain, the demonstration of copper granules was usually difficult even when the copper content was high. Occasionally, however, copper granules were seen in the protoplasm o f glial cells (Fig. 5) and in one case, in the hypothalamus. Although some glial cells, in which deposition of copper was observed, possessed normal appearing nuclei, others were swollen, having chromatin-poor nuclei. There remains a possibility that Alzheimer I type glial cells regarded as characteristic changes in the brain with H.L.D., are nothing but degenerated glial cells, the protoplasm of which has been destroyed by copper. and clinical types of H.L.D.

Recently, Arima et a/. (1963 b) performed a genetical analysis of 20 families with H.L.D. in children. By applying both Haldane’s formula and the formula for ‘single ascertainment’, it was concluded that the mode of inheritance of H . L . D . in children is probably autosomal single recessive as seen in adults. Then, applying Dahlberg’s formula, gene frequency and the incidence of the patients in Japan were estimated at 0.0033 to 0.0066 and 1.9 to 6.8 per 100,000 respectively. These estimates were calculated on the hypothesis that the hereditary factor was only single in H.L.D. From studies on patients with H.L.D. in New York, Bearn (1953) entertained the

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Fig. 5. Coprer granules in the brain i n Wilson’s disease (putamen). To find the copper granules in the brain is not easy. However, when they are found, they are located in and around the glial cells and in the epithelial cells of the small capillaries. In the nerve cclls, they have never been seen. Oil-immersion. Rhodanine-hematoxylin stain.

b b H-FAMILY

K - FAMILY

I- FAMILY

0 . Female 0 . Male / Examined Cases

Fig. 6 . Pedigree illustrating the 3 families with Wilson’s disease found in ‘Mikura’ Island, Japan. No other hereditary disease is seen i n these families. R r f e w n w s p . 2x3-7x4

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possibility that the hereditary factor was not a single one, or there might be some modifying lactors for the manifestation of the clinical features. Yamauchi (1959) performed a genetical analysis of 15 families with H.L.D., and postulated 3 factors for H.L.D.: factors M, H, and N, concerning abnormalities in copper metabolism, hepatic symptoms and neurological symptoms respectively. He reported that the frequency of clinical manifestations of H.L.D. corresponds very well with calculated values on the assumption that factors M and H are dominant and N is recessive. Besides such hereditary factors, on the other hand, environmental or other modifying factors might also participate in the development of the manifestation of clinical symptoms. On this problem, very interesting cases of H.L.D. were observed by us recently. These 5 cases of H.L.D. were members of 3 families, which belonged to a historically and geographically separated society on a small island (Fig. 6). In spite of the probability that these 3 families have derived from one common family and their environmental factors have been almost identical, different types of the disease were seen in each family in regard to the age of onset, clinical features or reaction to the treatment with chelating agents. In 2 patients from H family the onset occurred in the second decade of life and had a slowly progressive course with improvement by chelation treatment, while the patients belonging to K and I families showed symptomsin their childhood and poorly reacted to the treatment with chelating agents. Autopsy findings were also different. The pathological findings of one patient from H family, who died from another cause, consisted of marked changes in glial cells, scattered small lesions of demyelination, subcortical spongy atate and only slight changes in the nerve cells, whereas that of one patient from K family showed a definite cortical atrophy macroscopically and marked degeneration of nerve cells microscopically. These cases have led us to postulate that in addition to the factor producing copper metabolism abnormality, one or more modifying factors operate concerning clinical features, reaction to the chelation treatment and pathological changes of the brain. The classical classification of H.L.D. into Wilson’s disease and pseudosclerosis, may also be reevaluated from such viewpoint. As is well known, these 2 types had been regarded as 2 different diseases until Hall finally established their identity in 1921, although much remains to be clarified in regard to the difference between the 2 types. Recently, DennyBrown (1964) pointed out a difference in the reaction of these 2 types to the treatment by chelating agents. Improvement of tremor and dysphagia upon treatment with chelation is the rule in the adult type (pseudosclerosis), while uniformly disappointing results were obtained in thejuvenile type (Wilson’s disease) as far as the relief of dystonia is concerned. From this experience, a corresponding difference in the fundamental, biochemical defect has also been postulated between these 2 types. Further investigation is evidently required to clarify the pathogenesis of this disease. H E P AT1 C EN C E P H ALO P A T H Y

Definition and classijication

The central nervous system manifestations associated with severe liver diseases have been generally designated as hepatic coma. However, the term hepatic encephalopathy

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seems to be more appropriate, in view of the occurrence of various mental and neurological symptoms in this condition besides coma. Hepatic coma may be classified into acute and chronic forms according to the clinical course (Okinaka, 1961). The former is represented by acute yellow atrophy of the liver and the so-called terminal hepatic coma observed in the final stage of cirrhosis of the liver, and to the chronic form belongs the chronic portal systemic encephalopathy (or special type of hepatocerebral degeneration according to Prof. Inose) which may be seen in liver cirrhosis or Eck’s fistula. Hepatic encephalopathy due to chronic shistosomiasis japonica should also belong to the second category (Okinaka, 1961; Ogihara, 1962; Okinaka et al., 1963). This chronic form of hepatic encephalopathy has been especially well known among Japanese neurologists since Inose’s first report in 1950 (Inose, 1950, 1952). In these 2 forms of hepatic encephalopathy, at least 2 distinct sets of etiology might be considered according to the consensus of the opinions of many workers in this field: the factor of disturbance of hepatic function and the extrahepatic factor or portal systemic shunt. The former probably plays the main role for the occurrence of the acute form, and the latter for the chronic form of hepatic encephalopathy. Kitani (1960), who classified hepatic encephalopathy into 3 types according to the clinical features, that is, coma, intermediate and abnormal behavior types, was of the opinion that the coma type occurred mainly in hepatic insufficiency, and the abnormal behavior type was observed in patients with portal systemic shunt.

Inose’s special form or portal systemic encephalopathy In 1950, Inose (1950, 1952) pointed out that, among those cases reported as atypical forms of H.L.D., there exist special forms of hepatocerebral disease with characteristic clinical features of chronic relapsing coma and pathological conditions of the brain which are distinctly different from those in H.L.D. This type is also distinguished from acute hepatic coma in which there is marked involvement of consciousness, deterioration of liver functions, and fatal outcome. The main neurological and mental symptoms of Inose’s type are :relapsing disturbances of consciousness, mental deterioration and progressive neurological symptoms such as dysarthria, tremor, rigidity, athetoid movement and others. The characteristics of the pathological conditions of the brain are summarized as follows : (I) incomplete subcortical softening and spongy degeneration, (11) appearance of glial cells of Alzheimer I1 type with intranuclear inclusion bodies stained with Best carmine, and (111) absence of Alzheimer I type glial cells and Opalski cells. The liver showed atrophy with advanced fatty metamorphosis in 2 cases, cavernous angioma in one and occlusion of the inferior vena cava in one case. Although the etiological relationship between the liver and brain was quite obscure at that time, this attempt of h o s e to give this type a special position among the hepatocerebral diseases provoked a widespread interest among neurologists in Japan. The worldwide progress of studies on this problem as well as accumulations of clinical and pathological findings in Japan have made it clear that portal systemic shunt is essential for the development of symptoms of this type. Thus, this type of hepatocerebral disease, References p. 283-284

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which was originally classified from clinical and pathological aspects, is now designated ‘chronic porto-hepatic encephalopathy’ (Baltzan, 1957) or ‘chronic portal systemic encephalopathy’ (Sherlock et al., 1954) from the etiological point of view. ( C ) Portal systemic encephalopathy due to schistosomiasis japonica

Hepatocerebral disease due to chronic schistosomiasis japonica was first reported by Ariizumi in 1952. According to Ogihara (1962) who performed an epidemiological investigation in the Yamanashi district, where an areaof local infestationof schistosomiasis japonica was found, appearance of mental and neurological symptoms showed a very close relationship with signs related to portal collateral circulation whereas no correlation was demonstrated between neurological manifestations and the severity of the disturbance of liver function. Mental and neurological signs and symptoms observed in these cases were paroxysmal disturbance of consciousness, tremor, rigidity, appearance of pathological reflexes and exaggerated deep tendon reflexes. Blood ammonia level was found to be elevated as high as 200 ,ug/lOO ml during episodes of coma. From these observations, they concluded that such hepatic encephalopathy due to schistosomiasis japonica might belong to the same category as the special type of h o s e or porto-hepatic encephalopathy described by Baltzan. ( D ) Pseudoulegyria type of hepatocerebral disease (Shiraki)

Recently, Shiraki ( I 962) reported 5 cases of another type of hepatocerebral disease which he designated pseudoulegyria type of hepatocerebral disease. These cases were all males aged between 20 and 3 1. Though their early symptoms were indistinguishable from those of Inose type, all of them characteristically showed ‘Appallisches Syndrom’ in the terminal stage. From the pathological aspect, this type was characteristic in the topographic distribution of the lesions represented by severe involvement of the bilateral temporal lobules which showed an appearance similar to ulegyria. Microscopically, severe disintegration of the nerve cells and appearance of Alzheimer I1 type glial cells were noted in the atrophic cortex. Disturbance of liver function was mild in all cases and the liver commonly showed fatty cirrhosis. Tt remains to be determined whether this type of hepatocerebral disease is qualitatively different or only quantitatively different from portal systemic encephalopathy. The specificity of this pseudoulegyria type will be established upon accumulation of more clinical, pathological and biochemical findings. Pathogenesis of hepatic encephalopathy Ammonia metabolism In spite of many investigations, there still remain many unsolved problems regarding the pathogenesis of hepatic encephalopathy. Among several hypotheses for the mechanism of this disorder, the theory of ammonia intoxication is most important. Many workers have confirmed the correlation of hyperammoniemia and hepatic

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encephalopathy also in Japan. We (Watanabe, 1960) have also reported the absence of neurological symptoms in patients with a blood ammonia level under 100 ,ug/lOO ml, while hyperammoniemia of 200 pg/IOO ml or more usually produced a disturbance of consciousness. As mentioned above, we observed hyperammoniernia in patients with hepatic encephalopathy due to chronic shistosomiasis japonica. For the elevation of blood ammonia, portal systemic shunt is probably the most important factor. However, a decrease in the ability of the h e r to detoxicate blood ammonia should also be considered. Yoshida et al. (1954) investigated this problem and found a marked decrease in arginase activity in the liver of patients with various severe liver diseases. Kitani (1960; Omura, 1959) reported the highest blood ammonia level in abnormal behavior type among the 3 types and pointed out the important role of hyperammoniemia not in coma but in the abnormal behavior of the portal systemic encephalopathy. Emphasizing the similarity of abnormal behavior between portal systemic encephalopathy and psychomotor epilepsy, he advocated a hypothesis that hyperammoniemia produces abnormal behavior of this type through excitation of the limbic system. From experimental studies on amrnionacal encephalopathy, Hirai (1 963) reported that the first manifestation of ammonia intoxication was represented by those of hippocampal stimulation, followed by unconsciousness, tonic and extensor spasms, and eventually respiratory depression and death. These neurological changes in ammonia intoxication were similar to those in acute anoxia described by Himwich in both the nature and the order of appearance (Table I). He also confirmed experimentally the effect of ammonia in stimulating the hppocampus through recording subcortical and cortical EEG changes of cats injected with various ammonium salts consisting of synchronized, high voltage slow waves from the hippocampus, namely, hippocampal arousal waves (Fig. 7). To clarify the importance of the portal systemic shunt for the mechanism of hyperammoniemia, he injected 15N-labeled ammonia into normal dogs and those with Eck’s fistula and obtained the following results. The concentrations of 15N in the brain and blood were much higher and their decrease was more delayed in dogs with Eck’s fistula than in the normal. In the liver, normal dogs contained more 15N than those with Eck’s fistula. However, the mode of distribution of 15N in the various parts of the brain was the same in both groups as follows: cerebral cortex > thalamus > brain stem > cerebellum > limbic system > nucleus caudatus > hypothalamus in a decreasing order. According to Tsukiyama (1963), hyperammoniemia is required (though this is not a sufficient condition) for the appearance of triphasic waves, which have been well known to be fairly specific to hepatic encephalopathy. According to Mine (1960), flapping tremor, constituting one of the most important features of hepatic encephalopathy with grouping voltages of irregular periods and amplitudes, could also be produced by hyperammoniemia. From these clinical and experimental studies on ammonia metabolism in hepatic encephalopathy, it is quite possible that ammonia plays an important role in the attack of neuropsychiatric disturbances characteristic of portal systemic encephalopathy. Moreover, it seems likely that neurological manifestations in hepatic precoma, such as anxiety, confusion and flapping tremor are also caused by ammonia. However, References p. 283-284

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TABLE I COMPARISON O F SIGNS A N D SYMPTOMS I N ANIMALS WITH EXPERIMENTAL AMMONIUM POISONING A N D O F (A)

~~

Stage

ACUTE ANOXIA A N D (B)

HIPPOCAMPAL STIMULATION

Symptorns of anoxia

Syniptoms

Syrnptoms of ammonium intoxication

Localization

1

Salivation Motor excitement Clouded consciousness

Depression of cortical and cerebellar activity

Salivation Motor excitement

2

Loss of consciousness Myoclonic twitchings Clonic spasms Motor restlessness Dilatation of pupils Tachycardia Salivation

Release of subcorticodiencephalic region

Clouded consciousness Myoclonic twitchings Clonic spasms Motor restlessness Dilatation of pupils Tachycardia Salivation Vomiting Micturition Defecation

3

Tonic spasms Torsion spasms Independent movements of eyes

Release of midbrain

Torsion spasms Independent movements of eyes

4

Tachycardia Extensor spasms Dilated pupils

Release of upper medulla oblongata

Extensor spasms Dilated pupils

5

Bradycardia Respiratory depression

Release of lower medulla oblongata

Bradycardia Respiratory depression

- -~ Stage

Effect of hippocampal stimulation

Ammoniurn intoxication ~~

Behavior

Autonomic sign

Behavior

~ _ _ Autonomic sign

__.

1

Attention reaction

2

Facial twitching Mastication Contraversive turning Cataleptic

3

Jerking of face trunk limb Convulsion

4 Salivation Tachypnea Mydriasis Shivering

4

Micturition Defecation

Attention reaction? Facial twitching Mastication Vomiting

Salivation Tachypnea Mydriasis Shivering

Convulsion

Micturition Defecation

4

___

coma itself must be regarded as the response not only to ammonia but also to a number of other cerebral depressants resulting from hepatic failure. Factors other than ammonia ( a ) Short-chain fatty acids (SCFA). Recently, Takahashi (1963) emphasized the

HEPATOCEREBRAL DISEASE I N J A P A N

28 1

importance of short-chain fatty acids as a cause of hepatic coma. The narcotic action of this group of substances had already been studied by Samson in 1956, but no one has ever considered them in connection with hepatic coma. He determined the blood level of SCFA gaschromatographically in many patients with various diseases in-

Fig. 7. EEG changes after intravenous injection of ammonium carbonate. RPO = preoptic region; CM = centre-median nucleus (thalamus); PHy = posterior hypothalamus; AMY = amygdaloid nucleus; HIP = hippocampus; ANT SIG = anterior sigmoid gyrus (cerebral cortex). Note the appearance of hippocampal arousal waves after the injection, indicated by arrow.

cluding hepatic coma, and found a significant increase of SCFA only in the blood of patients with hepatic coma. The effect of SCFA upon electrical activities of the brain was observed by Muto (1964) in cats (Fig. 8). lnjection of this substance induced deep sleep patterns on the neocortex practically without effect on the activities of the limbic system. At times, triphasic waves were observed. From these observations, he concluded that SCFA mainly suppresses the midbrain neocortical reticular activating systems. This effect of SCFA on the brain is interesting in comparison with that of ammonia on the brain. ( b ) Uridine and cytidine. As well as many other toxic substances excessively accumulated in the body, deficiency of necessary substances for supporting the normal brain metabolism should also be taken into consideration as a factor causing hepatic encephalopathy. From this aspect, Yamasaki (Geiger and Yamasaki, 1956) demonstrated that perfusion of the brain with artificial blood mixtures maintained the uptake and oxidation of the carbohydrates for prolonged periods only if a liver extract or nucleosides such as uridine and cytidine were included in the artificial blood mixture. According to present knowledge, the pathogenesis of hepatic encephalopathy can be illustrated as in the following scheme (Fig. 9). References p.1283-284

282

M. Y O S H I K A W A , T. M O Z A I A N D S. H I R A I Before 1 AMY I UIP

.

I ANT SIG

.

7 min ofter

d

l

-

lsec

Fig. 8. EEG changes after intravenous injection of n-valeric acid. Note the deep sleep pattern with high amplitude slow waves and spindle bursts in the neocortex after the injection of 4 mM/kg of n-valeric acid. The electrical activities of the limbic systems are decreased to a lesser extent than the ncocortex, resulting in marked dissociation of the activities between neo- and paleocortex in the EEG taken 7 min after the injection. SUMMARY

An outline of recent advances in the clinical and experimental studies on hepatocerebra1 diseases in Japan are presented in 2 sections, namely, hepatolenticular degeneration (H .L.D.) and hepatic encephalopathy. Clinical statistics of H.L.D. in Japan based on 62 cases reported during the past 10 years indicated that more than 90% fell in the range of 5 to 30 years of age, and the most frequent signs and symptoms were Kayser-Fleischer corneal ring associated with neurological symptoms such as tremor and rigidity, in excellent agreement with the reports in the European and American literature. With the aid of biochemical diagnostic methods, on the other hand, many atypical cases have appeared more frequently, especially cases with only abdominal symptoms often found among children under 9 years of age. A close resemblance in copper metabolism was demonstrated between human fetus

283

H E P A T O C E R E B R A L D I S E A S E IN J A P A N HEPATIC

ENCEPHALOPATHY

I

I

I

ACUTE FORM

HEPATIC

CHRONIC FORM

1

INSUFF ICJENCY

F

DEFCIENCY FACTORS

1

EXCESS FACTORS

1

PORTAL-SYSTEMIC SHUNT

EXCESS FACTORS

(uridine cytidine. serotbnin 7 )

S.C.F.A.

---

short

chain

fatty

acids

Fig. 9. Scheme of the pathogenesis of hepatic encephalopathy. Details are given in the text.

and patients with H.L.D. A specific distribution of histochemically positive copper was also shown in the liver and brain of patients with H.L.D. Three stages in the pathological changes in the liver were distinguished, from detailed histochemical and morphological studies in accord with corresponding clinical manifestations. The need of a re-evaluation of the classical classification of H.L.D. into Wilson’s disease and pseudosclerosis is suggested, presenting instructive cases with different clinical types. In the second section on hepatic encephalopathy, divided into acute and chronic (or portal systemic) forms, the encephalopathy due to shistosomiasis japonica and socalled pseudoulegyria type are presented as special examples of the chronic form in Japan. Hepatic failure and portal-systemic shunt are considered to be responsible for the development of acute and chronic forms respectively. Ammonia, having been investigated from a new point of view and shown t o be a stimulant to the limbic system, is regarded as the most important factor for the episodic attack of neuropsychiatric disturbance characteristic of the portal-systemic encephalopathy, while coma itself probably resulted from a number of other cerebral depressants circulating due to hepatic failure such as short-chain fatty acids recently investigated in our country. REFERENCES A R I I Z U M I ,(1952); ~., Hepatocerebral disease based on liver cirrhosis due to Schistosomiasis japonica. J. Yamanashimen. Ass., 5 , l .

284

M. Y O S H I K A W A , T. M O Z A I AND S. H I R A l

ARIMA, M., e f a/. (1963a); Genetical studies on Wilson’s disease. I. Clinical and biochemical studies. Brain Nerve, 15, 21-28. ARIMA, M., et al. (1963b); Genetical studies on Wilson’s disease. 11. Mode of inheritance, geographical distribution and gene frequency. Brain Nerve, 15, 29-35. BALTZAN, M. A., (1957); Chronic porto-hepatic encephalopathy. J . Neuropath. exp. Neurol., 16,410421. BEARN, A. G.,(1953); Genetic and biochemical aspect of Wilson’s disease. Amer. J . Med., 15,442-449. CUMMINGS, J. N., (1948); The copper and iron content of brain and liver in the normal and in hepatolenticular degeneration. Brain, 71, 410-41 5. DENNY-BROWN, D., (1 964); Hepatolenticular degeneration (Wilson’s disease). Two different components. New Engl. J. Med., 270, 1149-1 156. GEIGER, A., AND YAMASAKI, S., (1956); Cytidine and uridine requirement of the brain. J . Neurochem., 1, 93-100. HALL,H. C., (1 948): La D&inkrescence Hkpato-lcnticulaire Maladie de Wilson-Pyeudoscl.4rose. Masson et Cie, Paris. HAROWITZ, F., (1930); Uber eine Anomalie des Kupferstoffwechsels. Z . physiol. Chem., 190, 72-74. HIMWCH, H. E., (1951); Brain Metabolism and Cerebral Disorrieeus. Williams and Wilkins, Baltimore. HIRAI,S., (1 963); Experimental studies on the role of ammonia in hepatic encephalopathy. Psychiat. Neurol. jap., 65, 827-841. INOSE, T., (1 950): A special form of hepatolenticular degeneration. Prychiat. Neurol. jap., 51,245-271, INOSE,T., ( I 952); Hepatolenticular degeneration, a special type. J. Neuropufh. exp. Neurol., 11, 401-408. KITANI, T., (1960); Hepatic insufficiency. J . Jup. Soc. int. Med., 49, 341-373. MINE,R., (1960); Electromyographic studies on flapping tremor especially on its relationship to hyperammonemia. Med. J . Osaka Univ., 12, 699-712. MOZA~, T., (1953); Studies on the copper metabolism in hepatocerebral disease. Nisshin Zgaku, 40, 202-209. MOZAI,T., et af. (1962): Abnormal copper metabolism and Kayser-Fleischer corneal ring associated with Schistosoma infection. Neurology, 12, 540-546. MUTO,Y., (1964); Effects of short chain fatty acid anions on the electrical activity of neo-, paleoand archicortical systems. Brain Nerve, 16, 601-607. OGIHARA, K., (1962); Studies of hepatocerebral disease: On the portal-systemic encephalopathy recognized in chronic schistosomiasis japonica. Psychiat. Neurol. jup., 64, 293-305. OKINAKA, S., (1 961); Neurological disorders associated with diseases of the liver. Proc. 7th Intern. Congr. Neurol., Rome. OKINAKA, S., et al., (1954); Pathogenesis of hepatocerebral disease: histochemical study of copper of liver and brain in Wilson’s disease. Arch. Neurol. Psychiat. (Chic.), 72, 573-578. OKINAKA, S., et al., (1961); Studies on hepatocerebral disease: hepatolenticular degeneration in Japan, with studies on copper metabolism. Neurology, 11, 792-799. OKINAKA, S., et al., (1961); Studies on hepatocerebral disease. IV.Portal-systemic encephalopathy in chronic schistosomiasis japonica. Arch. Neurol. (Chic.), 7, 1-9. OMURA, I., (1959); The role of hyperammonemia in hepatic encephalopathy. Psychiat. Neurol. jup., 65, 827-841. SAMSON, F. E., (1956); A study on the narcotic action of the short chain fatty acids. J. Clin.Invest., 35, 1291-1298. SHERLOCK, S . , et al., (1954); Portal-systemic encephalopathy. Neuroglial complications of the liver. Lancet, 267,453-457. SHIKATA, T., (1960): Pathological studies on the liver of hepatocerebral diseases. Recent Adv. Res. new. Syst., 5, 116-1 37. SHIRAKI, H., (1962); An autopsied case of the ‘Pseudoulegyric Type’ of the hepatocerebral disease. Prychiat. Neuro/. iap., 64, 305-318. TAKAHASHI, Z., (1963); Hepatic coma and short chain fatty acids. Clin. Neurol., 3, 344-349. TSUKIYAMA, K., (1963); Some approach to hepatic encephalopathy with special reference to the diagnosis and therapeutic agents. Clin. Neurol., 3, 358-366. WATANARE, H., (1960); Studies on hepatocerebral disease. Psychiat. Neurol. jap., 62, 235-264. YAMAUCHI, N., (1959); Die erbbiologischen Studien der hepatolenticularen Degeneration. Psychiat. Neurol. jap., 61, 995-1017. YOSHIDA, T., et al., (1954); Studies on liver function and liver enzyme activity. Jap. J. Gastroent., 51, 76-77.

285

Hemispherectomy in the Human with Special Reference to the Preservation of Function KOMEI UEKI Department of Neurosurgery, Brain Research Institute, Niigata University School of Medicine, Niigaat (Japan)

In contrast to previous discussions of the combined function of the cerebral hemispheres in general, it is now proposed to consider the effects of hemispherectomy and the role of the remaining cerebral hemisphere, not only in respect to somatic function but also in regard to mental capacity. Such a discussion can best be introduced by reviewing the signs and symptoms of typical cases and correlating these with the subsequent anatomical and neuropathological findings. In the series of cases under review, hemispherectomy was carried out in 10 patients with a diagnosis of infantile hemiplegia. These patients presented severe and intractable convulsive seizures and also displayed intellectual abnormalities characterized by aggression and violent outbursts of temper. The operative technique was the en-bloc removal of the affected hemisphere, including the caudate and lenticular nucleus but excluding the thalamus. Clinical benefit was obtained in every operated case. Owing to 2 deaths, a follow-up evaluation was possible in only 8 cases: 7 of these were followed for 6 to 8 years and 1 for 3 years. The first case to be considered is the most successful of the series. Its review will be followed by a discussion of the autopsy findings in 2 other cases, a comparison of the post-operative findings in 9 cases, and finally a consideration of the compensatory ability of the remaining hemisphere. T H E MOST S U C C E S S F U L C A S E W I T H E X C E L L E N T F U N C T I O N A F T E R O P E R A T I O N

Case history no. 5, M . Honda, male 17 years This patient was a forceps delivered breech presentation after a full-term pregnancy. Initial development was slow and artificial feeding was necessary. An episode of fever occurred at the age of 6 months. At the age of 12 months there was continuous melena for 1 month; convulsions occurred at this time. From thence onward, convulsions recurred with every episode of fever. In the first few years of life a paralysis of the right upper limb and a paresis of the right lower limb was observed. At the age of 4 years walking was barely possible. The child was somewhat retarded mentally; he entered primary school one year behind his school age and was among the lower half of his References p. 336-338

286

K. U E K I

class. He was able to write with his left hand. During his early school days his temper was very labile; he was prone to adhere closely to trivial matters and showed his feelings to the extreme. Convulsions recurred spontaneously about once per month and usually during play. These were characterized by a sudden stiffening of the body with a leaning or unsteadiness toward the right side; associated with these attacks was a transient loss of consciousness. As the child became older, these attacks became more frequent and severe and from the age of 10 onward they consisted of a generalized, predominantly tonic, convulsion with unconsciousness. No aura was present and there were no psychomotor features. At the age of 1 1, anticonvulsant medication was ineffective, but 2 years later medication was transiently successful in reducing the frequency of attacks from t a day to 7 or 8 a month. By this time, although the right-sided hemiparesis was considerably worse, the child was still able to take himself to school by street-car and by walking, mentally he showed a tendency to anger characterized by rage and the throwing and breaking of objects. At school his ability to keep up had lessened, and during his admission for operation it was noted that although he had reached sophomore standard, he read books suitable for junior standard. His admission to hospital was precipitated by 2 episodes of status epilepticus accompanied by fever and vomiting. Admission note. The patient was co-operative but was unable to control his temper and frequently became excited or violent with little provocation. He tended to be either autistic or depressed. Psychological testing showed a lower mark in the SuzukiBinet test, i.e., M. A. of 1 I years and 9 months and an I.Q. of 74. During the period of pre-operative observation he was still on medication, and seizures occurred consistently 2 or 3 times a month. Neurologically, there was a right spastic hemiparesis with atrophy of the muscles of the right upper and lower limbs. He walked with a limp and there was circumduction of the right leg. Movement of the right upper limb was present, particularly in the hand and fingers. H e was able t o put his hat on and off and to drink a glass of liquid with ease. The deep tendon reflexes were slightly increased in both the right upper and lower limbs, so also were the abdominal and cremaster reflexes. The plantar response (Babinski reflex) was extensor on the right, and the Chaddock sign was positive, There was a slight impairment of sensation on the right side of the body particularly in respect to discriminative sensation. Cranial nerve function was average. Pneumoencephalography showed a septa1 defect and porencephaly in the left parietal area. The EEG was characterized by low voltage slow waves in the fronto-parietal area of both sides and slower and lower voltage activity in the region of the porencephalic cyst. With activation, spike activity was observed in the left parietal area. The left cerebral hemispherectomy was performed (Figs. 1 and 2). Summary of the post-operative course. On awakening from anaesthesia the patient was alert, able to shake his hand and to move his lower limb unaided. The movement of the facial muscles was unchanged from the pre-operative state. For the first 24 postoperative hours there was conjugate deviation of the eyes to the left. As a result of the operative procedure there was a slight left oculomotor paresis and slight paresis of the limbs on the left side; rigidospasticity was decreased. There was a slight impairment of

NEUROLOGLCAL STUDIES O N HEMISPHERECTOMY

287

Fig. 1. Operated left cerebral hemisphere. Marked localized gross change, arencephaly. (A) Lateral surface. (B) Medial surface. References p. 336-338

288

K. U E K I

Fig. 2. Operated left cerebral hemisphere. (A) Frontal cut through the uncus (Uc). Widespread micropolygyric cortices are pronounced. Haemorrhagic foci due to the operative invasion are disseminated in the cortices, the white matter and the putamen (Pt). Myelination of the white matter is in general unsatisfactory, except for the internal capsule (IC) and the corpus callosum (CC). (B) Micropolygyric cortices as well as multiple heterotopic foci in the white matter with a well-developed myelination are pronounced. (C) Higher magnification of the heterotopic foci indicated by arrows in (B). Immature nerve cells are visible in the latter foci. (A-C, copper phthalocyanin with thionine.)

sensation on the right side of the body but no hyperpathia. Apart from an elevation of temperature during the first 10 days, the post-operative course was uneventful. On the 7th post-operative day he was able to walk unassisted. Two months after operation he was discharged from hospital. At this time, there was right homonymous hemianopsia with splitting of macula vision and a very slight left oculomotor nerve paresis. Limb and face movement, sensation, tendon reflexes and diencephalic-autonomic function were unchanged from the pre-operative state. On the basis of clinical observation, the emotional state was improved.

N E U R O L O G I C A L S T U D I E S ON H E M I S P H E R E C T O M Y

289

Following operation, the patient was readmitted 4 times for further study: at the 8th month, at the 1st year and 10th month, at the 3rd year and 6th month, recently, at the 6th year and 10th month. The accumulated and detailed data from these admissions are as follows.

( I ) Seizure incidence For one post-operative month the only medication was 0.2 g diphenylhydantoin and 0.015 g of phenobarbital. No seizures have been observed up to the present time.

(2) EEG findings Thirty days after operation. The hemispherectomized side showed low voltage flat activity with, again, low amplitude alpha waves in the parieto-occipital region. Because the amplitude and frequency fluctuations of the left-sided activity were synchronous with those on the right side, this activity was considered to be propagated from the right side. The activity on the right side had a slightly lower voltage than that observed pre-operatively, and 9-10/sec alpha waves predominated in the occipital area. No abnormal slow waves or spike activity were observed. It was concluded that the right-sided activity had shown an improvement over the pre-operative state and that it had now returned to normal (Fig. 3). Six months afier surgery. In the resting state the lO/sec regular cortical activity was present. No abnormal activity was recorded on the right side at rest or during hyperventilation. Activation with 200 mg Metrazol evoked a low voltage sporadic spike and sharp-wave discharge over the fronto-central area bilaterally, and especially on the right side. Three years and 8 months after surgery. In the resting state the right side showed a regular 9-l0/sec rhythm of moderate voltage. Some 15-20/sec low voltage fast activity was sometimes observed but this was considered to be within average limits. The activity after hyperventilation was also within normal limits. Six years and 8 months after surgery. On the right side the basic activity was normal. Waxing and waning were present; there was positive alpha-blocking and there was no evidence of slow activity or of seizure discharges. Hyperventilation did not produce any abnormal findings. On the left side there was low voltage flat activity as before.

(3) Mental and intellectual findings The patient was given several psychological tests including the Suzuki-Binet (1948), the Rorschach (19321 and the Bender Gestalt tests (1938). There was a fall in the Suzuki-Binet’s I.Q. 1 month after operation. This finding is explained as follows: ‘even though the patient before operation had displayed anti-social behaviour such as the appeal to violence, susceptibility to excitement with trifles and so on, he himself could have continued vigorous mental activities in his own way. However, owing to References p . 336-338

290

r I:

K. U E K I

a

P Lu k

h s

Case5. M.H.

3-5

- -

A f t e r operation ( Left Hemispherectomy)

5-7 C

Elm WY

0

2

6

++-VA-dVb”V

Fig. 3. Electroencephalographicfindings of Case 5. (A) Before operation. (B) One month after left cerebral hernispherectorny.

292

K. U E K I

the severe operative procedure, his mental activities were temporarily weakened thus resulting in a fall in the Suzuki-Binet’s LQ.’. The result of the Rorschach test at this period proved that, among prominent pre-operative characteristic manifestations such as explosiveness, deficiency of inward regulation, poverty in inner life and difficulty in solving problems, both the abilities to abstract and to form concepts were as poor as ever; the scope of mental activities was narrowed and the adaptability to the environment became diminished. A half year after operation, the Suzuki-Binet’s I.Q. returned almost to the preoperative level and the score on the WAIS scale showed that the verbal I.Q. was 93, a performance I.Q. 84 and the total I.Q. 88. These were more enhanced as compared with 1 month after operation. This fact seems to be related to an improvement in bodily conditions. The Rorschach test demonstrated that the total responses diminwas increased, indicating that this patient seemed to be improving to ished while F some extent. However, there remained the inclinations of both impulsiveness and excitability, a marked meagreness of imagination and abstract attitude, a vulgar view point, sterility in mental activities and scantiness of originality. Two years after operation, the Suzuki-Binet’s I.Q. rose to 81, and the WAIS scale quoted a verbal T.Q. of 91, a performance 1.Q. of 92 and a total T.Q. of 89. Thus the intellectual level showed a uniform improvement in scores, especially marked on a performance 1.Q. According to the Rorschach test, the total response was rough and vague, together with emotional instability and low emotional potentiality. After 7 years, the T.Q. showed more of a tendency to decrease, that is, the M.A. which was 13 years at 2 years after operation, became 9 years and 3 months, thus

+

TABLE I T H E P A T I E N T , MR. H O N D A , O N W H O M L E F T H E M I S P H E R E C T O M Y W A S C A R R I E D O U T AT T H E A G E O F

WAIS

Rorschach test

YEARS AND

8

MONTHS

Before operation

I month after operation

7 months afer operation

2 years after operation

7 years after operation

11 y and 9 rn 74

10 Y 63

llyand6ni 12

13y 81

9yand3m 58

Verbal I.Q. Performance I.Q. Total I.Q.

82 67

93 84

91 92

63

12

88

89

R F%

13 69 % 0

9 33 % 22 %

I4 42 %

Suzuki-Binet M.A. test

17

I.Q.

F-k %

0

zc P Corrected BRS

Bender Pascal Z score Gestalt test

5 -5

0 1

-38

0 2.25 1

0

14%

0 3 1 -20

12 50 % 16 % 0 2 1 -24

62

N E U R O L O G I C A L S T U D I E S O N HEMISPHERECTOMY

293

showing a fall in T.Q. from 81 to 53. The WAIS scale also presented low scores, the verbal 1.Q. being lowered to 63. The Bender Gestalt test showed the Pascal’s Z score to be 62. If remotely compared with intelligence, this score seems to be equivalent to that at 8 or 9 years of age. The Rorschach test gave a diminution of the total response but an increase in F%; thus there was presumably some disintegration (Table I). ( 4 ) Motor function on the right side

Pre-operativejindings. There was some difficulty in isolated closure of his right eye and slight facial paresis was observed on the right side. Ocular and tongue movements were normal; there was no deviation of the lower jaw on opening the mouth and lateral jaw movements were possible (Fig. 4). Rotation of the neck to the right or to the left was normal. Elevation of the right shoulder was markedly limited and attempts were associated with co-ordinated associated movements of flexion in the upper limb (Fig. 5 ) . Bodily rotation and flexion to the right was slightly inferior to that on the left. Although co-ordinated associated movement was observed in the upper limb, it was very slight at both the proximal and peripheral joints and the patient was therefore able to have almost isolated movements at these joints (Fig. 6). Elevation, adduction, and abduction at the upper arm and flexion and extension at the elbow remained the same as pre-operatively. Movement at the wrist was also adequate, but it was associated with hand and finger movement as in an artificial arm. Making a firm fist was accompanied with a moderate dorsal flexion at the wrist; opening of the hand was accompanied by slight plantar flexion, but co-ordinated associated movement was not

Fig. 4. Motor function of the face and the tongue. References p . 336-338

294

K. U E K I

Fig. 5. Elevation of the shoulder. (A) Healthy side. ( B ) Affccted side.

Fig. 6 . Movement at the wrist o f the affected side.

Fig. 7. Making a firm fist and opening of thc hand of the affected side.

present at the proximal joint (Fig. 7). There was some degree of isolated emphatic use of the thumb and index finger but the other 3 fingers were strongly associated with each other in any movement. Approximation of the thumb to the index finger was possible, but approximation o f the thumb and the little finger was not possible. Voluntary movement of the upper limb persisted quite well with slight co-ordinated associated movement, so that the upper limb was adequate for everyday use as for example, in taking a hat on and off, smoking, drinking, etc. (Fig. 8). Remarkably symmetrical associated movements were observed in the finger and wrist. Associated movement in

NEUROLOGICAL STUDIES O N HEMISPHERECTOMY

29 5

Fig. 8. Drinking water with the affected hand.

the lower limb was present but was of slight degree. The patient was able to raise his limb by extension of the knee joint to 35". There was strong ability of abduction, adduction and elevation at the hip-joint and also of flexion and extension at the kneejoint. There was flexion and extension of the foot and toes without the associated movement at the knee-joint even though foot-drop and limited movement were observed. There was a slight degree of limping and circumduction of the leg on walking. Post-operativejindings. Voluntary movement of the limbs immediately after operation was similar to that observed pre-operatively. On the 6th day after operation the patient was able to get out of bed; the next day he began to walk. At this time there was a transient conjugate ocular deviation to the left lasting for only 12 h. Owing to the operative procedure, there was a slight oculomotor paresis on the left; 2 months later this paresis had improved and by the 8th month it had disappeared completely. Post-operatively, there was a transient decrease in the grasping power on the involved side, but this returned gradually to the pre-operative level. Prior to surgery, grasping power was 25 in the left, and 9 in the right: 2 months post-operatively it was 26 and 7; at 8 months, 30 and 9, and at 22 months, 30 and 9. Follow-up tests were performed 5 times after surgery, i.e. at 2 months, 8 months, 20 months, 2 years and 6 months, and 6 years and 8 months. There were no changes in the motor function of the trunk, extremities, and cranial nerves. The patient soon regained voluntary movements equal to those possible before surgery (Figs. 9-14). He was able to dress und undress, to smoke and to drink (Fig.15). Limping and circumduction of the leg while he walked was not marked. Symmetrical associated movement between the wrist-joints on both sides and the fingers was the same as pre-operatively (Fig. 16). Some time after operation, rigidospasticity was decreased, and the patient remarked that he could References p. 336-338

296

K. U E K I

Fig. 9. Motor function of the face and the tongue.

Fig. 10. Elevation of the shoulder of the affected side.

Fig. 11. Movement at the wrist of the affected side.

NEUROLOGICAL STUDIES ON HEMISPHERECTOMY

297

Fig. 12. Making a firm fist and opening of the hand of the affected side.

Fig. 13. On the affected side; touch of thumb and index finger is possible, but that of thumb and little finger is not.

Fig. 14. Raising the lower limb. (A) Healthy side. (B) Affected side. References p . 336-338

298

K. U E K I

Fig. 15. Drinking water with the affccted hand.

Fig. 16. Syminctrical associated movement of fingers.

NEUROLOGICAL STUDIES O N HEMISPHERECTOMY

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move h s hand or foot more freely than before operation. However, one year laterthis rigidospasticity became slightly more severe than the pre-operative level. The patient complained not only of some stiffness in the movement at the extremities, but also at the hand and fingers. In addition, there was a feeling of limitation of movement, although these movements appeared unchanged to an observer. (5)'Rigidospasticity and reflex on the right side Pre-operativejndings. Slight rigidospasticity was present in the upper limb; there was a 160" contracture at the elbow and there was slight resistance to an angle of 110" to 160" in extension. There was contracture at the wrist, hand and fingers. On extension of the wrist to an angle of more than I65", there was simultaneous flexion of the hand and fingers. The lower limb showed slight rigidospasticity, and at the beginning of the flexion there was slight resistance at the knee. Foot-drop was present and dorsiflexion to an angle greater than 120" was not possible. The abdominal and cremasteric reflexes were slightly hypoactive, but the deep reflexes were moderately exaggerated. Ankle clonus was present and there was a Babinski toe sign with evidenceofslight fanning of the toes; Chaddock's sign was positive. Post-operative jindings. Rigidospasticity was only transiently decreased: 2 months after surgery it was of a greater degree than pre-operatively. However, 8 months after surgery it had returned to a pre-operative level. One year and 10 months after surgery it was slightly more marked than before surgery. The patient remarked that he was able to move easily for a while after operation but that gradually he experienced slightly more stiffness than pre-operatively. Superficial and deep tendon reflexes were all absent immediately after operation, but a few days later these reflexes reappeared and were almost comparable to those elicited prior to surgery. The findings at the 2nd, Sth, and 22nd post-operative month examinations gave results comparable to those observed pre-operatively. ( 6 ) Sensory function on the right side

( A ) Superjcial sensation ( I ) Tactile sensation. (a) Light touch. Slight impairment on the right side of the body before operation. Post-operatively there was a transient and marked loss; for example, perception of tactile stimulation when tested by touching with a writingbrush, was positive only over the face. This sensory loss had moderately recovered 2 months later and was equivalent to the pre-operative state. The normal side was demarcated on the mid-line of the face. (6) The threshold of tactile sensation on the right face was not high but compared with the left side, there existed slight impairment. In addition, there was a slight sensory impairment in the extremities and trunk, i.e. the threshold showed the increase of 1.5 to 3.0 times as much as that on the left. Post-operatively, the threshold was unchanged in the 2nd, 8th and 22nd post-operative months. The working normal value for threshold is between 8 and 12 g/mm2; more than 21 g/mm2 is considered to be References p . 336-338

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abnormal: on this basis, the patient's disturbance may be considered to be very slight. It was observcd that the threshold was rather variable and sometimes there appeared to be hallucinations of sensation. Prior to surgery, sometimes 'delayed sensations' and 'after sensations' were observed on the left but these signs had disappeared one year and 10 months after the operation. (2) Temperature sensation. Prior to surgery 'warm' sensation changed to 'heat' sensation on both sides of the body between 45 and 50". Over 50°, heat sensation was immediately experienced as excessive. Between 25 and 20" 'cool' sensation changed to 'cold' sensation and around 5" it became an excessive sensation. These changes were observed on the normal as well as on the affected side. On occasions the patient mistook an excessive heat sensation for an excessive cold sensation, but he was able to correct many of his mistakes. The range of the physiological zero point was narrow but nearly normal over the face. In all other parts of the body the range was wide and there was a slightly absent perception of temperature sensation: this perception at the post-operative 2nd, 8th and 22nd month remained the same as prior to surgery. ( 3 ) Pain sensation. ( a ) Pin prick. Before operation there was slight hypalgesia on the right side; this became a little bit more marked after surgery; a light pinprickwas perceived as 'pain' over the face, but on other parts of the body it was reported as a 'touch' sensation. This loss gradually improved and 2 months after operation pinprick appreciation was at the pre-operative level. ( b ) Threshold ofpain sensation. The threshold on the right side was higher than that on the left and thus there was slight hypalgesia on the right before surgery. After surgery, no change was observed at the 2nd and 8th month examinations. Prior to surgery, a touch at the right side of the body was experienced as a 'tingling' sensation : after surgery this paraesthesia disappeared completely. ( B ) Deep sensation ( I ) Joint sense. Although there was a slight loss of this sense prior to surgery, the patient was able to perceive a 10" movement at all joints. Tt was not until 2 months after operation that this defect improved and at that time the patient could discriminate a movement of 5" at all joints except at both the index-joint and the first toe-joint where 10" movement was necessary. The post-operative 8th and 22nd month examinations showed the same findings. ( 2 ) Vibration sense. Pre-operatively and at the 2nd and 8th month post-operatively, a 123Isec 'C' tuning fork was used; at the 22nd month examination a 1281sec fork was used; pre-operatively, when the patient perceived the vibration a slight shortening of perception time was observed. This ability was well preserved after surgery. The examinations at the 2nd, 8th and22nd months showed the same level as before surgery.

( C ) Discriminative sensation ( I ) Two-point discrimination. Pre-operatively, when tested in the circumferential direction of the extremities, the patient perceived the extreme distance of the width of that part as a single point in the upper arm, thigh and dorsum of the foot. In other parts, the distance between2 points had to be 2 or 3 times as great onthe right side as

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30 1

on the left. The threshold for discrimination at the post-operative 2nd and 8thmonths was the same as prior to surgery. One year and 10 months later, it showed improvement and the patient was able to distinguish 2 points i n parts of the body where he could only perceive 1 before operation; the threshold however on the right was 2 to 3 times as much as on the left. (2) Appreciation of touch localization. By the Volkmann’s method, there was a slight loss of sense of localization prior to surgery. In comparison with the normal side, the right side required a time 2 to 3 times as long as the left. There was no particular difference according to the parts of the body, but the face was more normal than other areas. The examinations of the 2nd, 8th and 22nd months showed no change. By naming the part touched, the ability at the 2nd month after operation was at the same level as pre-operatively; it had improved by the 8th month. One year and 10 months after operation, the patient was free of errors in the sense of lozalization. He stated that although he could now localize more exactly than was possible pre-operatively, he still had to give careful consideration to the stimulus in comparison with his ability on the left side. ( 3 ) Appreciation of weight. Tn the left hand, he was able to differentiate between 2 objects which were different in weight by more than 15 g. In the right hand the weight difference had to be more than 50 g in order to be recognized. At the 2nd and 8th month after operation the result was the same as that observed prior to surgery. One year and I0 months after operation, the ability to differentiate between weights was improved on both sides; the difference became 10 g on the left, and 25 g on the right. (The normal weight difference is within 30 g, so it may be said that no loss of this ability was observed.) ( 4 ) Appreciation of roughness and texture. (There is a one-step difference of roughness between cotton and silk.) Prior to surgery recognition was difficult. On the left he could recognize the difference with ease. At one month after operation, this ability was the same as prior to surgery. Although by the 8th and 22nd month periods there had been an improvement, the patient stated that it was more difficult to perceive this sense on the right than on the left (normal) side. ( 5 ) Appreciation of size. Pre-operatively the patient could only perceive a difference in size between 2 circles when 1 was more than I .5cm larger in diameter than the other. Two months after operation, perception of the size was better than pre-operatively ; a difference in diameter of 1 .O cm could now be perceived. Eight months after operation a difference in size of 0.5 cm in diameter was perceptible (the percentage of mistakes was 10%). One year and 10 months after operation, if tested by asking the difference in size of 0.5 cm diameter and if examined between the thumb and the index finger (which is an easy combination for perception), he recognized the similarity and difference of the circle without difficulty. However, recognition of the size on the right was more difficult than on the normal side where the perception of the size was complete and easy even if the difference between the diameter of 2 circles was only 0.5 cm. (6) Graphaesthesia. The ability to recognize the figure of numbers written on the skin had to be 2 to 3 times as large on the right side as on the left. In the lower limb the patient could not recognize a number that was 12 cm in size. Two months after operaReferences p . 336-338

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tion this ability to perceive appeared even in the lower limb. Although there was some variation dependent on the part of the body tested, at the post-operative 2nd and 8th months this ability as a whole returned to the same level as was observed prior to surgery. One year and 10 months later, there was increased perception of figures or letters on both sides. However, recognition on the right required the size of the number or letter to be 2 to 3 times as large as on the left in order to perceive the figure at the pre-operative rate. (7) Appreciation of shape. The appreciation rate was 25 "/,. This improved markedly post-operatively and at the 8th and 22nd months it became 75 %. (8) Appreciation ofform. Prior to surgery there was a moderate loss of form appreciation, and the rate was 55 %. Two months after operation the ability was found to have remained at the pre-operative level. At the 8th and 22nd month tests, the appreciation rate increased markedly to 85%. The patient stated that he could now identify the shape and form of objects more easily and clearly than he could prior to surgery. ( 9 ) Sensory inattention or extinction. ( a ) Bilateral double simultaneous stimulation. Before operation there was inattention to, but never extinction of, the stimulus. At the 2nd and 8th months after operation, the finding was the same as prior to surgery. One year and 10 months later there was no inattention to the stimulus. (b) Homolateral double simultaneous stimulation. Pre-operatively there was extinction in the peripheral point, the predominance in the body being as follows: face, upper extremities, trunk, lower extremities, and finally the foot. Testing at the 2nd and 8th months after operation showed the same predominance, in order, as prior to surgery; although there was inattention, extinction never occurred. One year and 10 months post-operatively, inattention was not noticed in the peripheral point (Table 11).

(7) Autonomic nervous system In respect to the autonomic nervous system, the post-operative course was uneventful. For several days post-operatively the patient complained of epigastric symptoms but he had no loss of appetite. On the 5th post-operative day the body temperature reached a maximum of 39.5". It then gradually subsided and by the 1 Ith day, was normal. There was some tendency of constipation for several days, but after 3 weeks the symptom disappeared. Two years and 4 months later, the patient had no marked change in weight or height. ( a ) Metabolism ( I ) Glucose metabolism. Blood sugar level (adrenaline and insulin tolerance tests). The adrenaline tolerance test at 1.5 and at 2 months after operation showed some tendency toward a slow reaction. Thc white blood cell count was normal. The insulin tolerance test was normal. Tests at both the 6th and 21st months after surgery were also normal. (2) Water metabolism, For several months after operation, the urinary output showed a moderately high percentage in 2 hours. Six months later, it became normal.

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TABLE I1 SENSORY FUNCTION FOLLOWING HEMISPHERECTOMY

Solid line shows no alteration and arrow shows improvement after surgery. .

~~

Affected side

Healthy side

~~

1 . Tactile sensation Light touch Threshold with von Frey’s hair 2. Temperature sensation 3. Pain sensation Pin prick Threshold with algesionieter 4. Joint sense 5. Vibratory sense 6 . Two-point discrimination 7. Appreciation of touch localization Volkmann’s method Naming the part touched 8. Barognosis 9. Appreciation of roughness and texture 10. Stereognosis Size Shape in 2 dimensions Form in 3 dimensions 11. Graphaesthesia 12. Sensory inattention or extinction Bilateral double simultaneous stimulation Hoinolateral double simultaneous stimulation

-

t

-

t t

-

t t

1.

t t 1. 1.

t t

( 3 ) Serum electrolytes. Examination 2 months after operation showed no change in Na, K or C1. (6) Basal metabolism The pre-operative test revealed -10.5 %; there was a gradual increase after surgery to -19% at 2 months, -15% at 6 months, and + l o % 2 years after operation. Vasomotor change (I) Electrocardiographic findings were normal after surgery. (2) Schellong’s test was normal both before and after operation. (3) The response of the blood pressure to a local cold stimulus did not show a change of more than 15 mm Hg. (4) The benzodioxan test on the blood pressure did not produce a reaction greater than 40 mm Hg. (5) Change of volume pulse wave of the skin by plethysmography. Before operation the stimuli of surprise, mental arithmetic, pin prick, pain and a drop of cold water, each produced a synchronous fluctuation with almost the same amplitude on both sides, Two months after operation, the same responses to these stimuli were found; the response appeared to be more marked, particularly on the involved side, but still remained within normal limits. (c)

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(6) Skin temperature. (a) When the surface of the naked body was examined in an air temperature of 22", with the exception of the face, the temperature was lower on the paralyzed side. The difference in temperature between the normal and the involved sides was as follows: lower limb, 3.5" to0.25"; upperlimb, 2.75" to0.5"; trunkand face, 0.5" to 0.0". In comparison with other parts, the upper limb showed a rather regular difference in temperature. One and a half months after operation there appeared some difference in the face (0.75'). The upper limb showed a difference of 3.0" to 0.5"; the lower limb 1.5" to 0.5". In comparison with the pre-operative findings, there was an increase in difference in the upper limb, and a decrease in the lower limb; as was also observed pre-operatively, the nearer the part was to the periphery, the greater was the difference. Observation at the 8th month after surgery still showed some difference in the face and also a difference in the upper and lower limbs which was almost the same as that recorded one and a half months after surgery. The axilla temperature was 0.25" -0.5" higher on the normal side. (6) Contrary to the above findings, when the surface of the naked body was examined in an air temperature above 30', the paralyzed side showed a higher temperature than the normal side; the difference was 0.5" in the face and 0.25"-0.5" in the upper limb. There was no difference in the trunk. One and a half months after operation, the findings were the same as before surgery. When the motor function in the extremities on the paralyzed side became more marked post-operatively, the difference between both sides became clearer; the converse was also true. (c) Examination at the 6th post-operative month in an air temperature of 22" and immediately after being in a refrigerator below -5" for 15 min, showed the following. Just after the subject entered the refrigerator, his skin temperature in the extremities fell rapidly and equally on both sides. After the subject came out of the refrigerator, his skin temperature rose rapidly and equally on both sides. No clear difference in temperature between the 2 sides could be observed. ( d ) Examination of the skin temperature of the arm after placing the foot in hot water at 42"-43', before and after operation showed a temperature rise in parallel, on both sides.

( d ) Bloodjindings After operation there was a tendency toward an increase in monocytes and a decrease in eosinophilic leucocytes. No relationship was found between the decrease in eosinophilic leucocytes and autonomic nervous system symptoms. ( e ) Endocrine system ( 1 ) Thorn test (ACTH 2.5 units intravenously and adrenaline 3 mg subcutaneously). Taking a decreasing rate below 40% as abnormal, this patient was found to be normal immediately after surgery. (2) Urinary 17-ketosteroids (Masuda method). Prior to surgery there was a normal value. After operation the 2nd and 6th month tests showed a slight tendency towards a decrease. Two years after operation there was a further decrease,

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(f) Sweating (except psychogenic sweating and pressure reflexes) (1) Minor method. Pre-operatively the paralysed side was dominant over the normal

side. Two months after surgery, this tendency became more marked, especially on the forehead. Gradually the difference between the two sides lessened. During the 6 and 12 month periods this tendency decreased further. (2) Galvanic skin resistance. At environmental air temperatures the skin resistance was between 1 ki2 and 10 Mil. After he had been lying on his back for 20 to 30 min in the hot room the patient’s sweating ability was measured by means of an electrode for a 15-min period at identical sites in the extremities on both sides. Prior to surgery the extremities on the paralyzed side were observed to be dominant. This difference had a tendency to increase during the 2 and the 6 month periods after operation; after 6 months it decreased. Identical points on all parts of the body were also tested. The results prior to surgery showed a predominance of sweating on the paralyzed side including the face. Post-operatively, the predominance between the right and left sides became marked, especially in the face. Nine months later this difference showed a tendency to decrease. ( 3 ) Method of counting the number o f ’ d r ~ posf sweat (Sofue methode, 1954). Before operation there was marked sweating of the paralyzed upper limb. One and a half months after operation the difference between the extremities of both sides began to increase; 9 months later this tendency decreased.

(g) The pubertas praecox syndrome This was absent. F I N D I N G S O F T W O A U T O P S Y CASES

In the series of 10 cerebral hemispherectomies, 2 cases died, and detailed autopsy examinations were performed. The first case, K.K., a 9-year-old boy, was in a favourable condition immediately following a left-sided operation. However, on the 22nd post-operative day, he unexpectedly expired during a sudden epileptic seizure. The second case, I.I., a 10-year-old boy also had a left-sided resection. Following operation his seizures were completely controlled with only a small amount of medication; he became very gentle in character and temper and was able to attend a special school for some time. During the 4 post-operative years in which he was observed he had occasional episodes of depression, anorexia and vomiting, which episodes frequently continued for one to several weeks. One night, he was found dead with a large quantity i f vomitus in his mouth. Case no. I A left cerebral hemispherectomy was performed along with a resection of the lateral marginal zones of the thalamus. The entire putamen, caudate and amygdaloid nuclei, as well as a large portion of the lateral nuclei but the medial nuclei of the globus pallidus were resected (Fig. 17). Macroscopically, there was atrophy of the resected left cerebral hemisphere (250 g) Rejertnccs p . 336-338

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Fig. 17. Operated left cerebral hemisphere. Case no. 1, K.K. (A) Lateral surface. (B) Medial surface.

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Fig. 18. Operated left cerebral hemisphere. (A) Frontal cut through the cranial striatuni. Cortical atrophy is almost absent, while that at the depth of the sulcus in a minimal degree is sporadically disseminated. Haemorrhagic foci due to the operative invasion are visible. Width of the white matter with a slight demyelination becomes in general narrow. (B) Frontal cut through the uncus. Similar to (A). ( C ) Frontal cut through Ammon’s horn. Similar to (A) and (B). (Copper phthalocyanin with thionine.)

and the lateral ventricle was slightly dilated. The most striking abnormality was a severe atrophy of the white matter including the centrum semiovale, with very little atrophy of the cortical gyri (Fig. 18). Microscopically, almost all of the white matter, with the exception of the internal capsule, was severely atrophic, although there was no definite lesion of focal demyelination or gliosis. The cortical gray matter, including the motor cortex, appeared to be of normal width and to have a normal cortical neuron pattern. Several atrophic foci of minimal degree were however sporadically disseminated microscopically along with a depopulation of the nerve cells, particularly in the depths of the sulci (Fig. 19). Among the remaining cortical neurons, there were many diffusely scattered shrunken forms. The complete loss of the pyramidal cells was noted in Sommer’s sector of Ammon’s horn (Fig. 20). The caudate nucleus, putamen and a part of the globus pallidus were not abnormal. Clinicaljndings. Although a subcutaneous haematoma was found on the head at birth, no other abnormality was detected from this patient’s family and viviparous histories. After the incision of the haematoma at the age of 7 days, clonic convulsions References p . 336-338

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Fig. 19. Cortices at the valky of the sulcus. (A) Area indicated by arrows in Fig. 18B. Patchy nerve cell disintegration (arrows) is present i n the deeper layer. (B) Area indicated by arrow with dot in Fig. 18B.Slight nerve cell disintegration occurs laminarily in the third layer. (Copper phthalocyanin with thionine.)

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Fig. 20. Lower magnification of Ammon’s horn in Fig. 18C. Disintegration of the nerve cells in Sonimer’s sector, the endplate and the fascia dentata is pronounced. (Copper phthdlocyanin with thionine.)

developed for 2 h . 0 ne night, at the age of 1 year and 10 months, the infant suddenly appeared to be in a dreamy state, and 30 min later, there was a clonic convulsion in the right extremities lasting for 2 h. Similar episodes occurred twice at the age of 2 years with subsequent paresis of the right extremities. The focal seizures gradually became generalized convulsions and also increased in frequency, and by the age of 10 they recurred up to 10 times per day. Intelligence became gradually retarded and the child always acted impulsively, then behaved outrageously. The child was admitted to the Department of Neurosurgery at the age of 9. He was extremely retarded and his intelligence was classified as idiocy. He behaved outrageously in an impulsive manner. The circumference of the head was slightly larger than average. There was a spastic paresis on his right side, including the face and the tongue. During activity, a slight athetoid movement was noted on the right side particularly on the neck and upper extremity. Voluntary movement was disturbed by this athetoid movement to the extent that no useful action was noted on the right hand. Although there were slight degrees of muscle atrophy and shortening of the right extremities, no obvious difficulties, such as a limp of the leg or circurnduction, were noted in walking. Deep tendon reflexes were increased OJI the right side and the abdominal reflex was decreased. There was also ankle clonus and a positive Babinski sign. Autopsy ,findings. The pharyngeal tonsils were approximately 3 times larger than usual. The lymphatic nodules of the intestine and spleen were underdeveloped. The thymus was atrophic and status lymphaticus was suggested. The liver revealed cloudy swelling. Macroscopically, the remaining right cerebral hemisphere, the basal ganglia and the brain stem did not show any dislocation towards the operated left side. A minimal degree of leptomeningeal thickening was seen on the cerebral convexity; no other abnormality, such as gyral atrophy, was noted in the cerebrum or in the cereRrfrirnccs p . 336-338

3 10

K. U E K I

Fig. 21. Autopsy case no. 1, K.K.

bellum (Fig. 21). Microscopic examination of the non-operated nervous system was performed as follows. (i) For the demonstration of the degenerated nerve fibres by Marchi’s method, the tissue was fixed in 10% neutral formalin for 20 h. Several thin tissue blocks 2 or 3 mm in thickness were then taken from the midbrain, medulla oblongata, the 2nd, 3rd, 6th, 7th and 1 Ith thoracic cord segments, as well as from the 2nd lumbar segment. These thin tissue blocks were then immersed in Miiller’s fixative for 4 weeks and subsequently in Miiller-osmium solution for 3 weeks. ( i i ) For the examination of retrograde degeneration of the thalamic nuclei, the brain stem nuclei, the remaining left and right thalamic nuclei as well as the remaining segments of the pons and medulla oblongata, the tissues were fixed in 10% neutral formalin. Serial sections, for Nissl and Kliiver-Barrera’s stains, were prepared from celloidin-embedded material; the thalamus 35 p i n thickness; the pons and medulla 25 p in thickness. Descending tract degeneration, particularly in the pyramidal tracts, was noted in the Marchi preparation. Midbrain. Marchi-positive granules were noted on the left side in the cerebral

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31 1

peduncle (fronto-pontine, cortico-spinal and temporo-pontine tracts), the red nucleus and the substantia nigra. The interpeduncular ganglion also contained these granules. The pallido-peduncular tract was not studied owing to damage of the tissue in this area. Marchi-positive granules, as noted in the fasciculus longitudinalis medialis, appeared to be significant even though this fasciculus often reveals such granules in normal brain tissue. In the tegmentum, the positive granules were dominant on the operated side but they were also present on the opposite side. These granules extended to the other side through the decussatio tegmenti dorsalis. Pons. The pyramidal tract and pontine nuclei revealed numerous Marchi-positive granules on the operated side. Deposition of these granules was traced to the lemniscus medialis; in some sections there was a further extension to the tegmentum. The degeneration of the tegmentum was predominantly noted on the operated side but it was also present on the opposite side. The granules were of various sizes. The motor nuclei of the trigeminal nerve and the mesencephalic nucleus also revealed degeneration on the operated side. A few fine granules were again noted in the pyramidal tract of the nonoperated side; this deposition however may be an artifact since the granules differed from those seen in the lateral fasciculus of the spinal cord (Fig. 22).

Fig. 22. Pons (Marchi).

Medulla oblongata. At the level of the hypoglossal nerve nucleus, the pyramidal tract on the operated side was occupied by numerous Marchi-positive granules. Some granules were traced through the medial lemniscus to the reticular formation on the same side. This pigment probably indicates the degeneration of the corticobulbar References p . 336-338

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Fig. 23. Medulla oblongata (Marchi).

tracts, and a few granules were diffusely terminated its far as the reticular formation on the opposite side. Bilatcral medial longitudinal fawicules, fascicules solitarius, hypoglossal nerve nuclei and tectospinal tracts were also Marchi-positive but i t was uncertain if this represented true degeneration (Fig. 23). Pyramidal dwussation. At this level, the major part of the degenerated fibres of the pyramidal tract crossed to the other side but some degeneration was also traced into the lateral fascicle on the same side. This latter degeneration was true degeneration and was not due to degenerated crossed fibres of the pyramidal tract on the noiioperated side since the fine granules of the pyramidal tract on this side wcre quite different from those of the uncrossed lateral fascicule on the operated side. It was therefore concludcd that these findings indicate the ‘presence of an uncrossed lateral fascicule’ (Fig. 24). Some Marchi-positive granules were also detected in the bilateral anterior pyramidal tracts as well as in Goll’s and Burdach’s tracts. The granules of Goll’s tracts were predominant on the operated side and were quite large. On the other hand. the granules of Burdach’s tracts were fine in size. Second and third thoracic cords. Marchi-positive granules were seen in the corticospinal tracts bilaterally, in the anterior pyramidal tract on the operated side and in the bilateral posterior fascicules. The granules in the lateral cortico-spinal tracts were prominent on the non-operated side. The granules on the operated side were approximately 14% of those on the non-operated side. The granules in Goll’s tracts were much more extensive than those in Burdach’s tracts (Fig. 25).

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Fig. 24. Pyramidal decussation (Marchi).

Sixth and seventh thoracic cords. The findings were the same as above (Fig. 26). Twevih thoracic cord. The anterior pyramidal tracts revealed extensive Marchipositive granules bilaterally. At this level, the degeneration of the dorsal fascicules was prominent in Goll’s tracts and was more extensive on the operated side even in the posterior nerve roots. Second lumbar cord. The anterior uncrossed pyramidal tracts were positive in minimal degree. Bilateral lateral fascicules of the operated and non-operated sides were also weakly positive. The degeneration of the lateral fascicule of the operated side was less than that of the thoracic cord. Marchi-positive granules of the lateral fascicule of the operated side were 1 1 % of those of the non-operated side (Fig. 27). As described above, the thoracic and lumbar cords demonstrated Marchi-positive granules in the pyramidal tracts and in the posterior fascicules and posterior nerve roots. These granules in relation to the posterior nerve roots could possibly be an artifact produced by autopsy but the degeneration noted at the level of the pyramidal decussation and the upper thoracic cord was definitely not artifactual. The granules were predominant in Goll’s tracts. Degeneration of the thalamic nuclei. It was confirmed in the serial sections that References p . 336-338

Fig. 25. Sccond thoracic cord (Marchi).

Fig. 26. Seventh thoracic cord (Marchi).

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Fig. 27. Second lumbar cord (Marchi).

thalamic nuclei on the operated side were retracted about 2.1 mm in comparison with those of the non-operated side. The hypothalamic nuclei were almost symmetrical. It seemed, at the time of operation, that a part of the medial nucleus of the left globus pallidus and the nucleus reticularis thalami were left intact. Microscopic examination of the autopsy material however disclosed that the ventral anterior, lateral posterior and the ventral posterior lateral nuclei were also resected in their lateral portions. The dorsolateral and lateral portions of the nucleus reticularis thalami were also not seen. Secondary necrotic processes following the operative procedure extended into the ventral anterior nucleus, the posterior portions of the dorsomedial nucleus, the nucleus reticularis thalami, the dorsolateral portions of the central medianum and the ventral posterolateral nucleus adjacent to the lamina medullaris interna and to the posterior portion of the pulvinar, which was itself divided by the necrotic lesion. Necrotic foci were also noted in the ventral portion of the pulvinar, tegmental radiation and in thelateral portions of the substantia nigra. Almost the entire medial nucleus of the globus pallidus was necrotic (Fig. 28). Nuclei on the operated side. f a ) Septum pellucidurn and fornix. Severe gliosis was evident in the septum pellucidum, fornix, and in the preoptic region. No obvious focus of demyelinization was present. Rcfcrcnres p.'336-338

316 K. UEKl

r,

0

Fig. 28. Degeneration of thalamus. a, nucl. anterior; c, nucl. centralis; CL, corp. Luysi; CM, corp. mammillare; m, nucl. medialis; pu, pulvinar; RN, red nucleus; rt, nucl. reticularis; SN, subst. nigra; STh, subthalamus; vli nucl. ventralis lateralis.

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( b ) Globus pallidus. Necrotic lesions with severe gliosis were noted in the remaining medial nucleus ; no normal neurons were present. (c) Nucleus medialis thalami. Extensive loss of neurons together with gliosis were

Fig. 29. Histological findings of thalamic nuclei. ( I ) Nucleus medialis. (2) Nucleus lateralis. (3) Nucleus ventralis. (4)Nucleus centralis medialis. (A) Operative side. (B) Contralateral side. References p . 336-338

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the main pathological features. A few degenerated neurons were detected in the caudal and medial portion of the nucleus. The lamina medullaris interna showed severe gliosis. A few remaining neurons of the central median and submedial nuclei were chromatolytic. There was a necrotic lesion in the dorsolateral portion of the central median nucleus. ( d ) Nucleus lateralis thalami. Nearly the entire dorsolateral nucleus was necrotic as the result of the surgical procedure. The dorsolateral portions of the lateral posterior nucleus were absent and were necrotic. The remaining lateral posterior nucleus showed severe gliosis and loss of neurons. The nucleus reticularis was damaged in its dorsal portions. The lateral nucleus in its ventral portion was relatively well preserved but scvcre gliosis and degenerated neurons were prominent. ( e ) Nucleus ventralis thalami. The anterior ventral nucleus showed severe gliosis and degenerated neurons. The lateral ventral nucleus was directly affected by the surgical procedure and contained a few neurons as shown by the retrograde degeneration. Gliosis was prominent in this nucleus. The posterior ventral nucleus showed extensive surgical damage with a few degenerated neurons and gliosis. ( f ) Nucleus centralis medialis thalami. No massa intermedia was detected in this case. Gliosis and degenerated neurons were seen in the anterior and posterior paraventricular nuclei (Fig. 29). ( g ) Epitlialamus. The nucleus habenulae was normal. ( h ) Metathalamus. Both lateral and medial geniculate bodies were exempted from the surgical resection but they were necrotic in their entirety except for a portion of the medial geniculate body. (i) Hypothalamus. No abnormality was detected in the supraoptic or paraventricular nuclei. A necrotic focus was noted in the anterior hypothalamic nucleus, but no other operative tissue destruction was noted. The lateral and ventromedial hypothalamic nuclei, as well as the mamillo-thalamic tract, demonstrated gliosis without obvious abnormality of the neurons. The mamillary body on the operated side showed depopulation of the neurons and gliosis. Cranial nerve nuclei. ( a ) Anterior portion of the midbrain. The red nucleus and the substantia nigra revealed gliosis. ( 6 ) Caudal portion of the midbrain and pons. At the level of the oculomotor and trochlear nuclei, severe gliosis was noted in the substantia nigra, and a necrotic lesion was seen in the lateral portion of the cerebral peduncle on the operated side. The oculomotor, trochlear and the mesencephalic nuclei of the trigeminal nerve failed to show any abnormality; the stratum griseum centrale was also normal. The nuclei of the mesencephalic tegmentum, including the peduncular tegmental nucleus as well as the nucleus caeruleus, all appeared to be intact. Several chromatolytic neurons were scattered in the pontine nuclei. The pyramidal tract showed gliosis in minor degree without obvious demyelination. The giganto-cellular and the other nuclei of the reticular formation, as well as the facial, abducens, vestibular and the trigeminal nerve nuclei, were all normal. ( c ) Medulla oblongata. No abnormality was detected in the medullary nuclei, including the hypoglossal, vagus, posterior fascicular, ambiguus, trigeminal and solitary fascicular. The reticular formation was also normal.

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Fig. 30. Operated left cerebral hemisphere. Case no. 2, 1.1. (A) Lateral surface. (B) Medial surface. References p . 336-338

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Fig. 31. Opcratcd left cerebral hemisphere. (A) Frontal cut through the level of the well-developed striaturn and globus pallidus. Cortical architecture is in general well-preserved, except for a slight disintegration of the parietal cortices (arrows with dots), while the width of the white matter with a slight deniyelination becomes diffusely narrow, particularly predominant in that of the parietal lobe. Both lateral and inferior horns of the lateral ventricle are conspicuously dilated. Basal ganglia are not affected. Haeniorrhagic foci due to the operative invasion are indicated by arrows. (B) Lower magnification of the cortical area at the valley of the sulcus indicated by arrow with dot in (A). A slight nerve cell disintegration occurs in the upper third layer. (A, Weil myelin; B, copper phthalocyanin with thionine.)

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Case no. II A left hemispherectomy was performed in a similar manner to that in case no. I. The striate body, amygdaloid nucleus and the lateral nucleus of the globus pallidus were completely resected. Macroscopically the resected left cerebral hemisphere showed diffusely clouded leptomeninges. The entire occipital lobe, in particular, was covered with severely thickened leptomeninges which were firmly adherent to the subjacent atrophic gyri (Fig. 30). Coronal sections of the hemisphere revealed extensive tissue destruction of the occipital lobe. Cortical atrophy was suspected in the remaining cerebral cortex. The centrum semiovale and subcortical white matter were diffusely and exceedingly atrophic and there was slight dilatation of the lateral ventricle. Microscopic examination revealed the so-called ‘status spongiosus’ of almost the entire occipital lobe. Cortical laminations were almost completely lost and were replaced by numerous proliferated glial cells and fibres; a few shrunken neurons remained. No myelin sheaths were detected in the atrophic white matter which revealed extensive gliosis and had a spongy appearance. These lesions in the occipital lobe did not appear to correlate with any arterial distribution. The frontal, parietal and temporal gyri revealed a minor but diffuse loss of cortical neurons. Among the remaining neurons, there were many scattered shrunken forms. The motor cortex maintained the normal 6 cortical layers but only a few Betz cells appeared normal. No focal demyelination was noted in the white matter which was, however, extremely atrophic along with a reduced number of myelin sheaths. In the resected basal ganglia, the striate body and the lateral nucleus of the globus pallidus failed to show any significant abnormality. In the internal capsule, no focal demyelination was detected (Figs. 31 and 32). Summarized clinical findings. The family history was not significant. Birth was normal without any evidence of asphyxia. On the 5th day after birth, while the boy was being given a bath, he suddenly had a series of convulsions which were followed by a state of asphyxia lasting for 30 min. Since the age of one year these convulsions recurred approximately once per month. At the age of 14 months the child was able to walk. At the age of 2 years and 5 months a severe attack of status epilepticus occurred; following this the patient was unconscious for 5 days and a right spastic hemiplegia resulted. The seizures commenced with twitching of the right face and spread to the right extremities; finally a generalized seizure occurred. Anticonvulsive drugs were not effective in controlling further seizures, and the child’s intellectual development was markedly retarded. Since the age of about 8 years the personality deteriorated, and the child became so ferocious that he was beyond the control of his family and neighbours. At the time of admission to the Niigata University Hospital a right spastic hemiparesis and right hemiatrophy were noted, the condition corresponding to WernickeMann’s type of spastic paresis. Walking was with a spastic gait. The deep tendon reflexes of the right extremities were increased. Patella and ankle clonus were present. The Babinski sign was positive on the right side and the corresponding abdominal reflex was diminished. The paraesthesia was of an obscure nature. Hidrosis was observed on the right side of the body. References p. 336-338

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Fig. 32. Operated left occipital lobe. (A) Severe cortical atrophy and deterioration predominant from the interwall to the valley of the sulci as well as widespread deterioration of the white matter are particularly predominant in the latero-ventral regions. (B) Lower magnification of the cortical region in (A). Coarse spongy, pseudolaminarily-distributed tissue disruption develops in the deeper cortical layers, while astrocytic proliferation is pronounced in the molecular layer. ( C ) A large number of the different-sized cystic cavities occur in all cortical layers and are in a coalescence. (D) Higher magnification of the comparatively well-preserved cortex at the medio-ventral portion in (A). Pseudolaminarily-distributed, finely-spongy tissue disruption occurs in the border area of the deepest cortical layer to the subcortical white matter (crosses). (A, copper phthalocyanin with thionine; B and D, H E . ; C , Bodian.)

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AutopsyJindings. There was extensive pneumonia of the right upper and lower lobes with petechial haemorrhages in both lungs. The trachea and bronchi contained brown aspirated substance. Congestion of the liver and kidney, and an enlarged spleen were prominent. There was a precocious growth of the pubic hair with hypertrophy of the testicles, particularly. on the left side. Within the space produced by the left hemispherectomy, there was a large cystic cavity formed by thin membranous tissue, which was adherent to the inner surfaces of the dura and the remaining brain tissue. This cystic cavity was filled with xanthochromic cerebrospinal fluid. No brain stem shift was noted (Fig. 33A). Astrikingfinding was the complete disappearance of the entire thalamic nuclei which were left intact at the time of the hemispherectomy. The leptomeninges covering the right cerebral convexity were diffusely clouded and somewhat thicker than usual. The cortex was normal. The lateral and the third ventricles, as well as the interventricular foramina, were dilated. The surface of the ventricle was markedly granulated. The septum pellucidum was displaced to the operated side. The corpus callosum was severely atrophic and paper thin. At the base of the brain on the operated side, the pons and medulla oblongata were atrophic and were dislocated posteriorly and inferiorly. A slight atrophy of the cerebellar hemisphere was noted on the non-operated side (Fig. 33A, B). Microscopic examination of the autopsied central nervous system was carried out after 10 P: neutral formalin fixation and after staining with hematoxylin-eosin, Kluver-Barrera’s and Holzer’s methods. The thalami, caudate and lenticular nuclei were carefully examined in coronal plane serial sections. ( a ) Area 4. The entire cortical gray matter was firmly adherent to the thickened leptomeninges. The superficial surface of the cortical layer revealed a spongy appearance with gliosis and granular atrophy (Fig. 34). The remaining cortical lamination appeared normal except for suspicious pyramidal cell depopulation and shrinkage. The remaining Betz cells appeared to be normal. ( b ) Frontal lobe. The leptomeninges and the subjacent cortical surfaces revealed similar but less marked findings to the above: these appeared to have been the result of a delayed meningitis. The cortical lamination was normal. No focal demyelination was detected in the frontal white matter. Other areas. Except for gliosis of the cortical surfaces, no significant lamina1 disturbance was noted in the cortical gray matter. (c) Ependymal layer. A considerably thickened ependymal cell layer had developed a diffuse granular appearance; there was severe gliosis and an increase in connective tissue. These findings were most prominent in the wall of the lateral ventricle, especially in relation to its frontal horn (Fig. 35). ( d ) Caudate and lenticular nuclei. N o marked change was present except for the subependymal gliosis. ( e ) Thalamus. The thalamic and hypothalamic nuclei on the operated side were absent. Microscopically, these areas were completely replaced by abundant glial scar tissue. No neuronal elements were detected. On the non-operated side the thalamus and hypothalamus were generally deformed but no definite neuronal abnormality was noted (Figs. 36 and 37). Referenres p . 336-338

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Fig. 33. Autopsy case no. 2,1.1. (A) Pons and medulla oblongata on the operated side are atrophic; cerebellar heniispherc, on the contrary, on the non-operated side is atrophic. (B) Dentate nucleus on the non-operated side is atrophic (arrows).

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Fig. 34. Spongy appearance with gliosis and granular atrophy in area 4.

Fig. 35. Considerably thickened ependymal cell layer develops a granular appearance (arrows in Fig. 36C). References p . 336-338

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Fig. 36. Basal ganglia on the non-operated side. (A) Frontal cut through the anterior commissure (AC). No marked changes are present, except for thc thickening of the ependymal cell layers. (B) Slightly caudal section to (A). Similar to (A). (C) Further caudal section to (B). Similar to (A).

(D) Further caudal section to (C). Similar to (A), (B)and (C). (E) Further caudal section through the pulvinar thalami to (D).Similar to (A), (B), ( C ) and (D). Remaining cerebral tissues of the nonoperated hemisphere are considerably shrunken, and a differentiation of thalamic and hypothalamic nuclei and cerebral peduncle becomes obscure. (Copper phthalocyanin with thionine.)

if) Midbrain, pons and medulla oblongata. A delayed form of granular ependymitis was again noted around the Aqueduct of Sylvius. Pale myelin staining of the colliculus rostralis was seen on the operated side. The entire cerebral peduncle of the operated side was extremely atrophic and diffusely demyelinated. The neurons of the red nucleus appeared normal. The substantia nigra was atrophic on the operated side, although no marked abnormality was noted in the melanin-containing neurons. The reticular zone on the non-operated side contained occasional perivascular phagocytes.

Fig. 37. (A) Higher magnification of the area indicated by arrows in Fig. 36D. Structures of both optic tract (OT) and supraoptic nucleus (SpN) are well preserved, however. (B) Higher magnification of the area indicated by arrows i n Fig. 36E. Completc demyelination, perivascular accumulation of fat granule cells and cellular increase are pronounced in the cerebral peduncle (CP), while the myeloarchitecture of the optic tract (OT) is comparatively well preserved. ( C ) Lower magnification of the degenerated thalamic nucleus indicated by arrows with dots in Fig. 36E. Pronounced cellular increase, and a few of the remaining neuronal cells with a calcification are visible. (D) Higher magnification of the calcified neuronal cells in (C). (E) Lower magnification of the substantia nigra at the nonoperated side in Fig. 36E. Pigmented nerve cells are well preserved, while pigmentary increase is pronounced in the reticular zone. (F) Higher magnification of the latter area in (E). A large number of the thioninophilic, tiny granules are present in the cytoplasmic processes of the astrocytes. (Copper phthalocyanin with thionine.)

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Fig. 38. Medulla oblongata. Severe atrophy and demyelination are restricted to the pyramidal tract on the left.

The longitudinal fasciculus and the pallido-peduncular tract on the operated side were also paler in the myelin preparation. Both locus caeruleus and trigeminal nerve nuclei were normal. The medulla oblongata demonstrated obvious atrophy and there was complete demyelination of the pyramidal tract on the operated side. The olivary nucleus on the operated side was slightly more atrophic than on the other side (Fig. 38). (g) Cerebellum. Although the cerebellar hemisphere on the right (non-operated) side was macroscopically smaller than that on the left, the molecular, Purkinje and the granular cell layers failed to show any definite abnormalities. The dentate nuclei were symmetrical without any depopulation of the neurons and without gliosis. The white matter showed no systemic or focal demyelination. The thickening of the leptomeninges was only probable (Fig. 39). ( h ) Spinal cord. Above the level of the thoracic cord, there was distinct macroscopic hemiatrophy on the right side. Microscopically, complete demyelination of both the crossed and uncrossed fibres of the pyramidal tract were noted. The crossed pyramidal tract demyelination was seen in the right lateral column at all levels of the spinal cord. The obvious demyelination of the uncrossed left anterior column was seen above the level of the lower thoracic cord. The anterior horn cells appeared normal. A mild pallor of the ascending tracts, particularly Goll’s tracts, was suspected in the myelin preparations but no other ascending tract demyelination was detected (Fig. 40). DISCUSSION AND CONCLUSION

After operation, 6 patients were free from seizures; 3 had good control with anticonvulsants; 1 patient died on the 21st post-operative day. In respect to seizure type, the onset in 1 patient was in the limbs on the normal side while in 2 patients the attacks were of generalized onset. That an epileptic discharge may be propagated along several

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Fig. 39. Frontal cut through cerebellar hemisphere. (A) Operated side on the left. Unsharply defined, diffuse demyelination of the white matter is marked, while both cortices and dentate nucleus are well preserved. (B) Non-operated side on the right. Similar to (A), but a demyelination of the white matter is less pronounced. Comparatively well-defined demyelinated focus (arrows) is restricted to the white matter adjacent to the dentate nucleus which is atrophic. (C) Lower magnification of the cerebellar cortex in (A). Slight disintegration of the Purkinje cells on the lower portion as well as loss, and pronounced cellular increase in the molecular layer develop. (A-C, copper phthalocyanin with thionine.) References p. 336-338

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Fig. 40. ( A ) Middle cervical cord. Severe atrophy and demyelination arc confined to the lateral column on thc right and the anterior column on the left. Slight demyelination occurs symmetrical bilaterally in the bilateral gracilc columns. (B)Lower thoracic cord. Severe demyelination is restricted unilaterally to the lateral column on the right, while that in the anterior column on the left becomes considerable i n a lesser degree. Slight dernyelination occurs bilaterally at the ventral part of the posterior column. (Copper phthalocyanin with thionine.)

pathways is an established fact in the human. Experimentally, in the hemispherectomized dog, we ourselves have observed that a convulsion could be initiated simultaneously on both sides when the remaining cerebral cortex was stimulated. Furthermore, in the monkey, as Walker ef al. (1956), Feath er a/. (1956) and Poggio r f (11. (1956) have shown, an epileptic discharge can be propagated in the cerebrum by many pathways when the abnormal discharging activity is moderate or strong. When the extrapyramidal nature of post-operative motor function is considered in the present series of cases, it is interesting to note that the clonic convulsions were more marked on the involved side or the body. In respect to the post-operative EEG, two findings merit special consideration ; firstly, the improvement in the activity of the remaining side; and secondly, the presence of electrical potentials on the hemispherectomized side. The cause of this improvement may be a release from a bombardment of abnormal potentials from the involved hemisphere, or it may be due to the absence of, or regression of, secondary epileptogenic foci in the healthy hemisphere, a phenomenon pointed out by many authors (Marshall and Walker, 1950). Section of the callosal fibres and the anterior and posterior commissures may avert the development of secondary bilateral synchrony. Thus, in the absence of epileptogenic lesions i n the remaining hemisphere, thalamocortical circuits may function more physiologically and the EEG is thus able to return to a more normal pattern. Many observers, in addition to ourselves, have

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noted the persistence of electrical potentials on the hemispherectomized side. In the present series, the fluctuation of these potentials was predominant in the frontal and occipital areas, whilst their amplitude was of the order of 5-30 p V . In 6 out of 10 cases potentials were recorded from the occi?ital area. As has been remarked earlier Obrador and Larramendi (1950), because these potentials on the operated side were synchronous with those recorded from the remaining side and because this correlation was less in a more lateral position, there was little doubt that the potentials themselves were derived from the remaining hemisphere. Probable conduction through the skull and scalp was also confirmed by the method of exchange of cerebrospinal fluid and air as reported by Cobb and Scars (1956) in the cat. In one case, the amplitude of the electrical potentials was the same post-operatively as pre-operatively. In another the potentials were increased after the air exchange. We were also able to confirm the observation of the above authors that without air exchange, slow potentials appear to be more easily conducted than fast potentials. In respect to psychological tests, the case under discussion had an I.Q. of 81 in the Suzuki-Binet test 2 years after surgery; there was then a rise for 2 years followed by a tendency to fall. Three additional cases were also given psychological tests, in particular the Suzuki-Binet test and the Rorschach test. Although these examinations were limited by the behavioural and emotional instability of these patients, the course of the mental and psychological states following hemispherectomy may be summarized as follows: I or 2 months after operation there was a fall in I.Q.; this finding may not be an absolute condition but rather a temporary state brought about by such a radical procedure as hemispherectomy. The emotional instability, illustrated in our series particularly by explosiveness and impulsiveness, may be reduced in degree. Adequate responses to stimuli gradually became evident and there was, to some extent, an enlargement of interest. However, the ability to integrate and to respond adequately to stimuli was as poor as ever; a fact which is probably related to a low level of intellectual development. Approximately 6 months after operation the M.A. and J.Q. in some patients reached the pre-operative levels while in others, a superior level was observed. The emotional state and the personality tended to become stabilized. Two years after operation, the I.Q. rose, and the results of the Rorschach test showed some improvement, even though there remained a deficit in abstract, in integration and in response with variety. Seven years after operation the I.Q. was inclined to fall as compared with the 2-year level. With the exception of one case (previously described) the M.A. reached a higher value. In the present series, no correlation could be found between psychological function and the laterality of operation. Those cases which showed an improvement in the EEG following hemispherectomy also showed an improvement in the I.Q. Because a routine operative procedure was adopted, it is assumed that the surviving cases possess a similar anatomo-physiological and pathophysiological state to the autopsied cases, i.e. a lack of tissue above the hypothalamus on the operated side. The Bender Gestalt test may be a useful index of brain damage, for it was observed that in the presence of brain damage this test had a strong tendency to fall. The absence of any marked fall inZ score wouldsuggest that hemispherectomy did not interferegrossRi,feiences p . 336-338

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ly with prcviously developed psychic activity; it should be pointed out in this respect, that the effect of hemispherectomy is to remove damaged brain tissue rather than to add damage to the brain. In a series of 28 cases of infantile hemiplegia, McFie (1961) reported that the intelligence quotients on the Wechsler-Bellevue scale tended to rise more following hemispherectomy than following a partial resection of cerebral tissue. In the instance of a patient who suffered from hemiplegia at the age of 1 year, he was able to show a definite rise in the I.Q. The following facts were also pointed out. There was no noticeable difference between the results obtained in right- or left-sided hemispherectomies ; there was a significant improvement in those patients in whom a normal remaining hemisphere and verbal intelligence had a tendency to be inferior to performance intelligence. In the casc of a 39-year-old white male, studied by Bruell and Albee (1 962), in whom the right cerebral hemisphere was removed for a tumour, there was marked but by no means complete, preservation of higher mental function, as judged by comparing pre-operatively and post-operatively 5 subjects of the Wechsler-Bellevue Tntelligence Scale, the Rorschach test, the Draw-a-Person Test and the Bender Gestalt Test. Furthermore, there was a perfect retention of language and no obvious difficulty in forming abstract concepts. While short-term planning was preserved, there were signs of impairment in long-range planning ability; there were also indications that the memory for remote and recent events had suffered. As Freud has shown, aphasia may occur as the result of a lesion on either side and be curable easily in infancy and childhood; a fact which suggests that cerebral dorninancy may not exist in infancy and childhood. None of the present series of cases of left hemispherectomy showed aphasia; and in the literature it has not been possible to find any instance of clear aphasia developing after a left hemispherectomy in infancy. In one of the present series of patients, a right hemiplegia and aphasia developed at the age of 5 years; however, the aphasia disappeared completely when the laterality of handedness changed from right to left, In this regard, Nielsen (1941) collected many such cases in which the cerebral dominancy transferred to the opposite side. Furthermore, Hiller (1954) and Zollinger ( I 953) reported a patient who recovered.from aphasia following a left hemispherectomy for brain tumour. It was the impression of Achslogh and Ectors (1954) that the indication for hemispherectomy must be palsy developing prior to the development of the speech mechanism. Although Krynauw (1950) considered that the caudate nucleus plays an important role in motor function after hemispherectomy, the results of the present series of cases do not lead us to the same conclusion. While there have been many reports of hemispherectomy in instances of brain damage occurring at delivery, there are only 2 cases to be found who have useful voluntary movements in the fingers - our own case and a case of French and Johnson (1955). This case in our own series exhibits the highest degree of motor function which one hemisphere can produce and no doubt indicates that there already existed in the healthy hemisphere (as the result oftransference) a high degree of compensation. It would seem that the earlier the brain is damaged, or the more immature the encephalization, the more marked is the compensation of function that may be expected.

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There are 2 hypotheses to explain the preservation of motor function in the limbs contralateral to the side of hemispherectomy: one supposes a function of the basal ganglia on the operated side, and the other a function in the remaining hemisphere which is transmitted, in particular, by the ipsilateral, lateral corticospinal tract. Ziilch (1954) believed that the motor function seen in the contralateral limbs after hemispherectomy was the result of activity in the extrapyramidal basal ganglia-midbrain system ; he based his conclusions on the resemblance of this motor activity to that seen in the new-born infant in whom the pyramidal tract is myelinated only to the midbrain and the extrapyramidal tract is completed only in its caudal part from the striatum. He also paid attention to the involuntary, complicated associated movement exhibited in human midbrain preparations as reported by Gamper (1926), and he pointed out that the movements seen in man in the recovery stage from decortication or destriation, were similar to the jumping-like movement of the decorticated new-born monkey or the crawling movement of reptiles. We ourselves observed that the thalamic dog, when supported, could perform clumsy walking movements and that he could flounder when he was lowered to the ground. Kennard (1944) reported that the decorticated adult monkey could only exhibit floundering movements in response to noxious stimuli but that the decorticated young monkey could right himself, squat, and also dash against and cling to objects. These movements observed in the dog and monkey, are not of voluntary, but are rather of the nature of a righting reflex. On the other hand, Tower ( I 940) reported that in the monkey the basal ganglia are able to initiate some degree of volitional movement receiving impulses from the cortical extrapyramidal system. In the present series of cases, we attribute the remaining movements in the post-operative state to the basal ganglia system because of the fact that typical co-ordinated associated movements are prominent. However, in the one case reported above in whom there was a retention of a high degree of voluntary activity, we must assume that structures in addition to the basal ganglia were responsible. The existence of the uncrossed lateral pyramidal tract in man, as verified in the dog, cat, monkey and chimpanzee, was first reported by Pitres (1882). Sugiyama and Ueki (1 962) clearly demonstrated in an autopsy case following hemispherectomy, that the uncrossed lateral corticospinal tract branches from the main tract at the decussation of the medulla and has a volume of 14% at the second thoracic level and 1 1 X at the second lumbar level as compared with the contralateral tract. Fulton and Sheehan (1934) estimated this uncrossed lateral corticospinal tract as 10% of the contralateral tract in the chimpanzee whereas Glees and Cole (1952) estimated it at about I5 % of the contralateral main tract in the monkey. The data of Sugiyama and Ueki are therefore very interesting i n view of these reports. Von Monakow (1895) and Dejerine (1901) first reported a compensating hyperplasia of the lateral pyramidal tract when the contralateral lateral pyramidal tract was degenerated from the time of early infancy; since this work appeared, many similar studies have been recorded. Verhaart (1950) failed to observe an increase in the number of nerve fibres but noted hyperplasia of the individual fibres. He inferred that this hyperplasia may occur when the contralateral tract degenerates prior to complete maturation of the nerve fibres. We must therefore conclude that in the patient in whom we ourselves observed a References p . 336-338

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high degree of voluntary motor function after hemispherectoniy, the uncrossed ispilateral lateral corticospinal tract played a leading role in the preservation of motor function. I t may also be said that the earlier the main contralateral lateral tract is damaged the more easily are impulses conducted in this ipsilateral lateral tract. There are 2 hypotheses that concern the post-operative preservation of sensory function following hemispherectomy : one assumes a function of the remaining thalamus on the operated side, and the other assumes astrong ipsilateral representation of sensory function in the healthy hemisphere. On the basis of autopsy material derived from 2 cases, the latter hypothesis is thought to be the more likely one. A bilateral representation in the thalamus has been established both electrophysiologically and histologically in the cat and monkey: by Dusser d e Barenne and Sager (1931, 1937) by strychninization of the thalamic nuclei, and by Mountcastle and Henneman (1949, 1952) by stimulation of peripheral nerves. In human hemispherectomy, it is certain that the ipsilateral thalamus plays an important role in the preservation of post-operative sensory function. Austin and G r a n t (1955) reported a case in which tactile and pain sensations were preserved almost at normal values after hemispherectomy. However, the autopsy material in this instance showed degeneration of the posteroventral nuclei. In a case of hemidecortication reported by Powell (1952) the reticular nucleus, the midline nuclei, the intramedullary nuclei a n d the central median nucleus of the thalamus were almost normal, but the lateral nuclei, the ventral nuclei and the dorsomedial nuclei were degenerated. In the Laine and Gros case (1956) not only were these nuclei degenerated but also the intramedullary and midline nuclei. Therefore, because of the degeneration of the lateral part of the thalamus, including the primary somato-sensory centre, as a result of operation, the thalamic extralemniscal sensory system (intramedullary nuclei, central median nucleus, reticular nucleus, midline nuclei) participates in the preservation of post-operative sensory function. Bowsher (1957) is of the opinion that non-localized delayed pain with ‘after-sensation’ was conducted by this extralemniscal sensory system. Conversely, localized, sharp, immediate pain without ‘after-sensation’ may be conveyed by the spino-thalamic tract. There are many reports in the literature concerning the participation o f the extralemniscal sensory system in somatosensation, for instance those of Hecaen et al. (l949), Starzl e t d . (1951, 1952) and Walker (1943, cited in Bowsher, 1957), etc. In the series of cases herein reported, the patticipation of the extralemniscal sensory system of the operative side cannot be considered. Many reports refer to the sensory tract ascending in the spinal cord and terminating in the ipsilateral thalamus; Foerster (1927) showed that unilateral, anterolateral chordotomy could not control severe pain, and French and Peyton (1948) pointed out the existence of bilateral sensory tracts in the spinal cord on the basis of his experiences with chordotomy. In the human many fibres of the spino-thalamic tract arrive at the contralateral reticular formation ; one part then crosses and terminates in the central median nucleus while the other uncrossed portion terminates in the intrarnedullary nuclei. It is said that only a few fibres of the spinothalamic tract reach the ventral nuclei of the thalamus directly. Quensel (l898), Bowsher (1957) and Kuru (1949) verified in autopsy material following chordotomy that one part of the spinothalamic tract crosses again through the posterior commis-

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sure and then reaches the ipsilateral thalamus. On the basis of these reports there is therefore sufficient reason to consider that in our case sensory impulses arrived at the ipsilateral thalamus. Three patients out of 10 complained of hyperpathia. This symptom was characterized by a transient but rather severe pain response to a tactile, pain or temperature stimulus; the patients feared to be touched or to be exposed to wind. The symptom was most noticeable on the second and third post-operative day; it gradually lessened from about the 10th day onward and disappeared completely in 3 weeks. Two cases were affected on the paretic side only; i n one case the normal side was also slightly affected, all 3 cases had associated high fever and repeated vomiting, both of which disappeared coincidently with the hyperpathia. It may thus be that hyperpathia is related to autonomic dysfunction: it is interesting that in these 3 cases pubertas praecox was later observed. Wilson (1927) regarded the frequent occurrence and fluctuation of autonomic symptoms in hyperpathia as important. Shiramizu (1958) also noticed autonomic symptoms in all 7 patients with hyperpathia. Fujii (1951) and Abe (1955) showed, through the use of toxic and lytic agents, that the autonomic nervous system provides an ‘adjusting sensory function’. After hemispherectomy in our series, glucose and water metabolism as well as serum electrolytes, remained unchanged. A disturbance of the regulation of body temperature was observed for quite a long period of time, but it is possible that this may be a result of the wide opening made into the lateral ventricle at operation. As far as clinical examination could reveal, vasomotor function was not altered by operation. In respect to the regulation of skin temperature, it was observed that pre-operatively the affected side was readily influenced by the environmental temperature and that this tendency was transiently exaggerated post-operatively ; 2 months after operation it returned to the pre-operative level. After surgery, sweating on the involved side became more profuse, particularly on the forehead, but after several months this returned to a preoperative level. That the forehead was predominant is of interest in view of the concept that sweating fibres may be associated with the trigeminal and facial nerves. As other authors have remarked, pubertas praecox may be a noteworthy aftereffect of hemispherectomy. In the present series of 10 operated cases, 2 patients were past puberty; 1 died on the 21st post-operative day and 1 could not be followed after operation; of the 6 remaining cases all were verified as pubertas praecox. In summary, it is concluded that the 8 cases reported above had a similar postoperative neuro-anatomical basis to the 2 autopsy cases studied in detail macroscopically and microscopically, and therefore valid conclusions on pathophysiology may be drawn. I n these former cases there were several grades of post-operative preservation of somatic function as well as intellectual and psychological function. It is of particular interest that the first case presented had an absence of cerebral tissue above the hypothalamus on one side; the post-operative somatic function shown by this case may be the ultimate in function of one hemisphere. It seems certain that the ipsilateral lateral corticospinal tract is largely responsible for the motor function observed and that the ipsilateral hemisphere, including the thalamus, is responsible for the remaining sensory function. Rcfivrnces p 336-338

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SUMMARY

Hemispherectomy was carried out in 10 patients in whom a diagnosis of infantile hemiplegia had been made; clinical benefit was obtained in every case. The most successful case with excellent function after operation is presented in detail and it is suggested that the results indicate that there is a limit to the capacity of the remaining hemisphere which limit is imposed by the mediation of the normal functions of both hemispheres by one hemisphere alone. Two deaths occurred in the series and detailed autopsy examinations are presented. The clinical signs and symptoms are correlated with the anatomical and neuropathological findings. (I) Tn respect to the effect of operation on seizure incidence and EEG findings, our results are almost the same as those reported by other authors. (2) The course of the mental psychological states following operation may be summarized as follows: I or 2 months after operation there was a fall in test scores; 1 or 2 years after surgery an improvement in scores was shown; after 7 years the scores presented a tendency to decrease. (3) In one case there were useful voluntary movements even in the fingers and also a preservation of epicritic sensory functions on the involved side after operation. It has been clearly demonstrated in autopsy material from one case following hemispherectomy, that the uncrossed lateral corticospinal tract branches from the main tract at the decussation of the medulla and descends in the spinal cord. In the other autopsy, in which the patient died 4 years after operation, the cerebral tissue above the hypothalamus was absent on the operated side. From these neuro-anatomical findings it seems certain that the ipsilateral lateral corticospinal tract is largely responsible for the motor function observed and that the ipsilateral hemisphere, including the thalamus, is responsible for the remaining sensory function. ( 4 ) In this series pubertas praecox was a noteworthy after-effect of hemispherectomy.

REFERENCES ABE,K., (1955); Clinical study of sensation. Nagoya Igaku, 70,670-690 (in Japanese). ACHSLOGH, J., A N D ECTORS,L., (1954); Cited in Yearbook of Neurol. Psychiaf. Neurosurg., 1954-1955, 427428. AUSTIN,G. M., AND GRANT,F. C . , (1955); Physiologic observations following total hemispherectorny in man. Surgery, 38, 239-258. BENDER,L., (1938); A visual motor Gestalt test and its clinical use. Anter. orthopsychiat. Ass. Res. Monogr., 3. D., (1957); Termination of the central pain pathway in man: The conscious appreciation BOWSHER, of pain. Brain, 80,606-622. BRUELL, J. H., AND ALBEE,G . W., (1962); Higher intellectual functions in a patient with heniispherectorny for tumors. J . cons. Psychol., 26, 90-98. COBB,W., AND SCARS, T. A,, ( I 956); The superficial spread of cerebral potential ficlds. Some evidence provided by hemispherectomy. Electroenceph. din. Nerrrophysiol., 8, 717-718. DEJERINE, J., (1901); Cited in Nathan and Smith’s paper. DUSSER DE BARENNE, J. G., A N D SAGER,O., (1931); uber die sensible Funktionen des Thalamus opticum der Katze. Z . Neurol. (Berlin), 133, 231-272. DUSSERDE BARENNE, J. G., AND SAGER,O., (1937); Sensory functions of the optic thalamus of the monkey ( M a c a w s rhexis). Arch. Neurol. Psychiaf. (Chic.), 38, 913-926.

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FEATH,W. H., WALKER, A. E., AND WARNER, W. A,, (1956); Experimental subcortical epilepsy. Arch. Neurol. Psychiat. (Chic.),75, 548-562. FOERSTER, O., (1927); Die Leitungsbahnen des Sclimerzgefiihls und die chirurgische Behandlung der Schnierzzustande. Urban & Schwarzenberg, Berlin. FRENCH,L. A., AND JOHNSON, D. R., (1955); Observations on the motor system following cerebral hemispherectomy. Neurology, 5, 11-14. FRENCH, L. A,, AND PEYTON, W. T., (1948); Ipsilateral sensory loss following cordotomy. J . Neurosurg., 5, 403-404. FUJII,T., (1951); Clinical studies on the sensory disturbances (first report). Psychiat. Neurol. jap., 53, 339-355 (in Japanesej. FULTON, J. F., AND SHEEHAN, D., (1934); The uncrossed lateral pyramidal tract in higher primates. J . Anat., 69, 181-187. GAMPER, E., (1926); Bau und Leistungen eines menschlichen Mittelhirnwesens. Z . Neurol. (Berlin), 102, 154-235. GLEES,P., AND COLE,J., (1952); Ipsilateral representation in the cerebral cortex, its significance in relation to motor function. Lancet, 262, 1191-1192. HECAEN, H., TALAIRACH, J., DAVID, M., A N D DELL, M. B., (1949); Cited in Bowsher’s paper. HILLER, W. F., (1954); Total left cerebral hemispherectomy for malignant glioma. Neurology, 4, 71 8-721. KENNARD, M. A., (1944); Reactions on monkeys of various ages to partial and complete decortication. J. Neuropath. exp. Neurol., 3, 289-310. KRYNAUW, R. A., (1950); Infantile hemiplegia treated by removing one cerebral hemisphere. J. Neurol. Neurosurg. Psychiat., 13, 243-267. KURU,M., (1949); Sensory paths in the spinal cord and brain stem of man. Igakusoho, Sogensha, Tokyo and Osaka. LAINE,E., ET GROS,C., (1956); L’Himisphkrectomie. Masson et Cie, Paris. MARSHALL, C., AND WALKER, A. E., (1950); The electroencephalographic changes after hemispherectomy in man. Electroenceph. clin. Neurophysiol., 2, 147-1 56. MCFIE,J., (1961); The effects of hemispherectomy on intellectual functionings in cases of infantile hemiplegia. J . Neurol. Neurosurg. Psychiat., 24,240-249. MOUNTCASTLE, V. B., AND HENNEMAN, E., (1949); Pattern of tactile representation in thalamus of f ~ . ,85-100. cat. J . N e u r f f p ~ y s i f 12, MOUNTCASTLE, V. B., AND HENNEMAN, E., (1952); The representation of the tactile sensibility in the thalamus of the monkey. J . comp. Neurol., 97, 409-431. NATHAN,P. W., A N D SMITH,M. C., (1955); Long descending tracts in man. I. Review of present knowledge. Brain, 78, 248-303. NIELSEN, J. M., (1941); A Textbook of clinical Neurology. P. B. Hoeber (p. 236). OBRADOR, S., AND LARRAMENDI, M. H., (1950); Some observation on the brain rhythms after surgical removal of a cerebral hemisphere. Electroenceph. clin. Neurophysiol., 2, 143-146. PITRES, A . , (1882); Note sur I’etat des forces chez les hemiplegiques. Arch. Neurol. (Paris), 4, 26-41. POCCIO, G. F., WALKER, A. E., AND ANDY,0. J., (1956); The propagation of cortical after-discharge through subcortical structures. Arch. Neurol. Psychiat. (Chic.), 75, 350-361. POWELL, T. P. S., (1952); Residual neurons in the human thalamus following hemidecortication. Brain, 75, 571-584. QUENSEL, F., (1898); Ein Fall von Sarcom der Dura Spinalis. Neurol. Zbl. (Leipzig), 17, 482-493. RORSCHACH, H., (1932); Psychodiagnostik. Hans Huber, Bern. SHIRAMIZU, S., (1958); Investigation of thalamic syndrome. Recent Arlvanc. Res. N.S., 2, 585-621 (in Japanese). SOFUE, E., (1954); The Function of’Hypothalamus. Igakushoin, Tokyo (p. 141) (in Japanese). STARZL, T. E., TAYLOR, C. W., A N D MACOUN, H. W., (1951); Collateral afferent excitation of reticular formation of brain stem. J . Neurophysiol., 14, 479-496. STARZL, T. E., A N D WHITLOCK, D. G., (1952): Diffuse thalamic projection system in monkey. J . Neurophysiol., 15, 449-468. SUGIYAMA, Y . ,AND UEKI,K., (1962); Pathoanatomical study on cerebral hemispherectomy in man. J.J.S.S.,63, 609-632 (in Japanese). SUZUKI, J., (1948); Intelligence Test. Toyotosho, Osaka (in Japanese). TOWER, S. S., (1940); Pyramidal lesion in the monkey. Brain, 63, 36-90. VERHAART, W. J. C., (1950); Hypertrophy of pes pedunculi and pyramid as result of degeneration of contralateral corticofugal fiber tracts. J . comp. Neurol., 92, 1-15.

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VON MONAKOW, C., ( I 895); Cited in Nathan and Smith’s paper. WALKER, A . E., (1961); The march of focal motor epilepsy. Neurol. med.-chir., 3, 1-28. WALKER,A. E., POGGIO,G. F., AND ANDY,0. J., (1956); Structural sprcad of cortically-induced epileptic discharges. Neurulugy, 6, 616-626. WECHSLER, D., (1944); The Measurement of Adult Intelligence. Williams and Wilkins, Baltimore. WmTtikiMER, M., (1923); Studies in the theory of Gestalt psychology. Psychol. Forsch., 4, 301-350. WILSON, S . A . K . , (1927); Dysanesthesia and their neural correlates. Brain, 50, 428-473. ZOLLINGER, R., (1953); Removal of left cerebral hemisphere, Report of a case. Arch. Neurol. Psychiar., 34, 1055- 1064. ZULCH,K . J . , (1954); Neurologische Befunde bei Patienten mit Hemisphcrectomie wegen friihkindlichcr Hirnschaden. Zbl. Neurochir., 14, 48-63. ZULCH,K. J., (1956); Zentrale Storungen der Motorik und ihre Restitution nach dem Pradilektionstyp von Wernicke-Mann. Dtsch. Z . Nervenkr., 175, 217-~232.

339

Reconsideration of Ventrolateral Thalamotomy for H yperkinesis HIROTARO NARABAYASHI

AND

KISOU KUBOTA

Department of Neurology, Juntendo Medical School, Tokyo (Japan) and Departrneni of Neurophysiology, Institrite of Brain Research, Faculty of Medicine, University of Tokyo, Tokyo (Japan)

INTRODUCTION

Since Hassler and Riechert ( I 954a, b), Cooper and Bravo ( I 958) and others applied it to parkinsonian patients, ventrolateral thalamotomy (VL-thalamotomy) has been one of the main procedures in the field of stereotaxic surgery for various extrapyramidal disorders. Although the recurrence of the symptoms is often experienced, VLthalamotomy is highly successful not only in alleviating the rigidity and tremor of parkinsonians, but also hyperkineses of athetotic or dystonic patients. The techniques of VL-thalamotomy were originated and have been established from daily practices of adventurous surgeons on a trial and error basis. It is noteworthy that experimental neurophysiology does not provide us with a theoretically solid basis for the practice; and there seem to exist no definite or conclusive ideas among stereotaxic surgeons about the following basic questions, namely in which - small - part of the thalamic nuclei a surgical lesion should be made, how the size of the lesion be circumscribed, etc. In German schools the target for VL-thalamotomy is somewhat elaborately described in which the VL nucleus is divided into two or three groups mainly from the anatomical data: the v.0.a. (nucleus ventralis oralis anterior), receiving fibers from the pallidum through ansa lenticularis and Forel H field; and the v.0.p. (nucleus ventralis oralis posterior), receiving outflows from the cerebellar dentate nuclei. A lesion within the former is good for alleviating rigidity, and one within the latter is good for tremor (Hassler and Riechert. 1961). Morphologically speaking, the term VL-thalamotomy is sometimes used loosely and rather ambiguously in most other schools. Sometimes it means surgery on the ventrolateral part of the thalamus and not the exact nuclear group. Hence the question can be asked, whether the surgical invasion should be confined strictly to certain small anatomical structures such as v.0.a. and v.0.p. or should involve its neighboring areas. The aim cmf this article is to make this situation clearer and to analyze the effects of the so-called VL-thalamotomy. A fundamental difficulty encountered during the surgical procedure is to assess the exact localization of the lesion, which is only possible on post-mortem histological examination. I t seems impossible to determine the exact location in each living case, even with complementary help of the several brain atlases and of radiological measureReferences p . 349

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ment. In pathological cases with high degrees of brain atrophy, measurements from the normal brain atlases are not directly applicable. To overcome these difficulties, an attempt has been made to determine the location physiologically in each patient. For this an electrophysiological approach has been applied to delineate the VL nucleus, especially its ventral and posterior border, which will be described herein. METHODS

It is known that stimulation of the VL nucleus in both human and experimental animals evokes rhythmic potentials (augmenting and recruiting responses) in the various cortical areas (Dempsey and Morrison, 1942; Schlag and Balvin, 1964; Housepian and Purpura, 1963; Yoshida rr a/., 1964). Our techniques for stitnulating the thalamic areas and for recording EEG or E M C activities are described elsewhere (Yoshida rt al., 1964; Ohye et a / . , 1964). Several scalp electrodes are placed on the premotor and motor regions. One cortical electrode is placed on the dural surface of the trephined area, mostly in the premotor region. The stimulating electrode is a very thin stainless steel concentric needle, having 0.6 mm external diameter and 0.3 mm internal diameter with a tip separation of 0.5 mm. The needle is inserted stereotaxically into the thalamus with the patient in the supine position under the guidance of long distance radiography (4 m in lateral view and 2 m in the anteriorposterior direction). Electrical stimulation (6 cis, less than 30 V and I msec, or 60 cis, less than 20 V and 1 msec) is applied to the points within the thalamus during stepby-step insertioas of the electrode. Effects on the muscles are recorded electromyographically on the ink-writing oscillograph. Two disc electrodes are placed on the surface of the muscle belly, 3 to 5 cm apart from each other. The grades of tremor and muscle stiffness are examined and are objectively evaluated by reading the integrated EMG discharge using an appropriate circuit as previously described (Ohye et al., 1964). From the posterior area behind the V L nucleus physiologically determined (postVL area, presumably the ventralis intermedius nucleus, V.im.), the evoked potential I S recorded after stimulation of the ulnar nerve (1 cis, 1 msec). The nerve is stimulated through two directly inserted needles or through two surface plate electrodes around it. Evoked E M G s are simultaneously recorded bipolarly through needles from the muscles innervated by the ulnar nerve. The recording electrode from the thalamus is the same one that is used for the thalamic stimulation. The radiological standard for measuring the location within the thalamus is as follows : the basic horizontal plane is the intercommissural line between the upper edges of the anterior commissure and the posterior commissure, and the basic vertical plane is an assumed line perpendicular to this at the midpoint between these commissures. It is edmated that the lower border of the VL nucleus of the adult Japanese lies on or a few mm above this basic horizontal plane. And the posterior border of the nucleus will be slightly behind this basic vertical plane. For the convenience of later description, the authors’ arbitrary standard point of insertion is usually settled at a point 1 or 2 mm behind the midpoint on the intercommissural line (SP). Laterally

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the SP is located about 12 to 13 mm from the midline. The lateral border of the nucleus may be less than 17 or 18 mm from the midline. The ventral and slightly medial part below or ventral to the nucleus is called by the authors’ group the sub-VL area, which would approximately involve the Forel H field (Ohye et al., 1964). Campotomy (Spiegel ef al., 1963), sub-thalamic surgery (Adey et al., 1959) and Forel H surgery (Jinnai and Nishimoto, 1963) would involve this area. The area which we call V.im. (post-VL area) is located 16 or 17 mm posteriorly from the anterior commissure in adults and probably 2 or 3 mm frontal to the posterior nuclear group. Its vertical level is about 4 to 6 mm above the intercommissural line, and its lateral distance from the midline is 12 to 15 mm, which is slightly lateral to the VL. RESULTS

(I) The V L nucleus The VL nucleus may be configurated physiologically by observing the rhythmic

C

Fig. 1. Superimposed responses from parietal regions in a conscious parkinsonian patient (a, b), and in an anesthetized cerebral palsy patient (c). The upper trace is from the scalp electrode and the lower trace is from the cortical electrode. Upward deflection represents negativity, the reference being at the nose. Thalamic stimulations (30 V, 6 cis, 1 msec) were given a t 20 mm (a), 7 mm (b) and 10 mm above SP (c). From Yoshida et al. (1964). Rpferenrrr p . 349

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potentials of the EEG traces in response to low frequency stimulation of the various thalamic parts (Yoshida et al., 1964). When the stimulating electrode was located 10 to 20 mm above the SP in wideawake parkinsonian patients, the evoked potentials of both scalp and dural leads consisted of the slowly developing surface negative and succeeding surface positive waves (Fig. la). These waves were recorded from practically all scalp areas of both sides (nonspecific dif€use distribution). However, when the electrode tip was deepened to 2 mm above the SP, the potentials changed into a sharper negative-positive complex, as seen in Fig. 1b. And those were accompanied by the initial positive potential often in the cortical lead (lower trace in Fig. lb) and extremely rarely in the ipsilateral parietal scalp lead. By contrast with the former response, the latter was recorded exclusively from the parietal regions of the same side (specific distribution).

Fig. 2. Summary of the distribution of the structure capable of evoking a rhythmic potential in conscious parkinsonian patients and unconscious cerebral palsied patients. A, A , B, and B' are from the parkinsonian, while C, C', D, and D' are from the cerebral palsied. Thalamic points, which elicited the rhythmic potentials with the lowest intensity, are projected on the lateral view (A and C ) of the radiological findings as illustrated in E, which is modified from Schaltenbrand and Bailey's atlas, and on the anteroposterior view (B, D and F). Filled circles represent the point of threshold for the augmenting response in parkinsonian (A and B) and cerebral palsy (C and D). Open circles represent the point of threshold for eliciting the non-specific slow negative potential in parkinsonian (A and B). Straight short lines in A', B , C , and D' represent the extent of the thalamic structure in producing the rhythmic potentials either augmenting or non-specific, at a stimulus intensity less than 20 V and projected on the lateral view (A' and C ) and on the anteroposterior view (B' and D'). In all figures, the horizontal coordinate line is CACP line, crossing being at the anterior commissure. From Yoshida et al. (1964).

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In cerebral palsied patients wherein general anesthesia was introduced, the negativepositive complex with diffuse distribution was not observed on stimulation of any areas within the thalamus. Instead, the specific complex was clearly observed on stimulations of several to 10 mm above the SP (Fig. Ic). Fig. 2 summarizes the distribution of the points, of which stimulation at the lowest intensity (less than 20 V) elicited the typical rhythmic potentials in parkinsonian and cerebral palsy patients. The distribution agrees quite well with the ventrolateral nucleus of the thalamus described in the brain atlases. Thus, it appears possible to identify the configuration of the VL nucleus by these physiological methods in both conscious and anesthetized patients. This method has been found reliable in determining the VL nucleus in more than 200 cases, and even in the difficult cases with highly atrophied brains.

(2) The sub-VL area Thus the location capable of inducing the evoked potential similar to the augmenting response of the experimental animal in each case was considered as the physiologically determined VL nucleus, which enabled us to differentiate an area below the VL (2 to 5 mm below the VL) from the VL nucleus in observing the effects on motor symptoms by high frequency stimulation of parkinsonian patients.

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Fig. 3. Effects of the sub-VL area stimulation upon the tremor. EMGs are from forearm flexors and extensors (flex., ext.) of the right or left side (r or 1). EEG traces at the left in each pair are from lateral parietal region (1-P or r-P). A and B, stimulating electrode within VL. C and D, electrode is moved several millimeters downward from the EEG sensitive point, and the EEG of the upper trace produced by the same stimulus (6 c/s, 20 V, 1 msec) becomes weaker as shown in the lower trace beneath an arrow. Bars below EMG response indicate the sub-VL area stimulation (10 V, 60 cis, 1 msec). From Ohye et al. (1964). References p . 349

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When the stimulating electrode was within the VL nucleus as determined above the effect was an increase in the tonic discharges, and also an enhancement of the stretch reflex discharges. Suppression of the rigidity was not observed. The parkinsonian tremor was influenced either increasingly (Fig. 3a) or decreasingly (Fig. 3b). When the grade of the tremor was not so high, it tended to be enhanced by the stimulation being associated with an enhancement of the rigidity, and when it was violent, it was usually suppressed (or desynchronized) with an increased muscle tone. Since the authors’ needle was inserted into the nucleus via anterolateral to posteromedial direction with an angle of 70 to 75 degrees to the intercommissural line in the lateral view, the insertion tracks probably passed the v.0.a. rather than the v.o.p., which would result in more favorable effect on the muscle rigidity than on tremor. Even in the insertion of the needle to the somewhat posterior direction which passed through the v.o.P., as far as judged from X-ray readings, the assumed VL nucleus showed the same or similar motor effects. The sub-VL area, where the scalp rhythmic evoked potentials were not obtained by low frequency thalamic stimulation (even at relatively high intensity, 20 to 30 V), gave a quite different response. High frequency stimulation produced mostly an increase (C) or decrease (D) of tremor without being accompanied by an increase in muscle discharge. Thc sub-VL area is probably the complex of many different pathways. for example, pallidothalamic, cerebellothalamic or pallidorubral, and dctailcd analyses will be made later.

( 3 ) The a m 1 poslerior to VL, ( V . im.) An area posteriorly close to the VL nucleus is called the post-VL area, which presumably corresponds to the ventralis intermcdius nucleus (V. im.). This nuclear area dces not seem to be well separated from the VL cytoarchitectonically. According to Hassler’s intcrpretation, the V. im. nucleus is the area on which the afferent fibers from the vestibular nuclei would terminate (Hassler, 1959). Electrical stimulation at this area did not evoke marked rhythmic activities o n the scalp EEC. Therefore. to observe the disappearance of the rhythmic potentials on stimulation during the course o f clectrode insertion would be useful for knowing the border between two nuclei. From this area it was possible to record thc evokcd potential, if the peripheral nerve such as the ulnar nerve was excited by its low threshold stimulation. Fig. 4 illustrates such potentials consisting of a positive deflection of less than 100 p V . Its latency was 10 to 14 msec during stimulation of the ulnar nerve at the elbow and wrist joint. The threshold intensity of the nerve needed to elicit this thalamic positive potential was compared with that needed to evoke contractions of the forearm muscles. The former was always as low as, or slightly lower than (0.8 times), the latter. This potential attained its maximal size at the intensity of approximately twice the threshold of the muscle response. The area from which this potential could be recorded seemed to be localized, because, if the recording electrode was moved anteriorly or posteriorly 2 to 3 mm, it disappeared. Conduction velocity of the nerve fiber responsible for the production of this potential was measured by stimulating fwo sites along the ulnar

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nerve as in the illustrated sample. It gave rise to the value 94 m/sec, which is faster than that of the efferent motor fibers (56 mjsec). High frequency stimulation of this area produced no apparent specific sensation, probably indicating that the needle tip was not within the specific sensory relay nuclei such as for the skin. These positive potentials were not obtained within the VL. Furthermore, it was found in a limited number of observations that where the poten-

Fig. 4. Superimposed evoked potential recorded from the area behind the VL, presumably V.im. Stimulation (3 cis, 0.3 msec) was applied supramaximally to the contralateral ulnar nerve at the wrist joint (upper trace A ) and elbow joint (lower trace B) through two inserted wires attached closely to the nerve. The distance between two stimulating sites (negative poles) was 28 cm. Time, 10 msec, amplitude 30 p V .

tial was recorded, touching the skin innervated by the ulnar nerve did not elicit a clear evoked potential. This suggests that this small area was different from the area where the fibers transmitting skin sensation would terminate. The anatomical structure is not histologically identified yet, but it appears to exist between the VL and the posterior nuclei. By the stimulation (about 60 cis, 20 V, 1 msec), the tremor was facilitated or produced. Changes of tonic muscle discharges were not apparent. In parkinsonians it was found that a small lesion of 3 to 4mm diameter within this area improved the tremor. However, the rigidity was not alleviated at all. In order to reduce rigidity, it was necessary to make another small lesion within a lower part of the VL nucleus. In two cases of athetotic cerebral palsy a limited lesion within 0.1 sec l

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Fig. 5. E M G discharges evoked by stretching the muscle in a dystonic patient. At the elbow joint the left biceps brachii muscle was passively extended from the flexed position during the time marked by Str. Rcfcrcnccs p . 349

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Vim. was also found to be non-effective to the ‘fluctuating rigido-spasticity’. These cases were later reoperated and an additional lesion in the VL or the sub-VL area was made, which resulted in a successful reduction of the rigido-spasticity. This experience indicated that V.im. surgery has no influence in reducing muscle hypertonicity. TEerefore this nucleus, posterior to VL, should not be considered the target of choice in surgery for rigido-spasticity nor for parkinsonian rigidity.

INTERCOLLICULAR DECEREBRATION

0

STRETCH

too

200

300

400

ANEMIC DECEREBRATION

0.1 SEC

Fig. 6. Discharge patterns of the single neuromuscular units (NMUs) from the ankle extensor in the rigid state produced by intercollicular decerebration (Sherrington type, upper diagram) and anemic decerebration (Pollock-Davis type, lower diagram) in the cat. NMU activities are evoked by muscle stretch, as indicated by bars. Spike-to-spike intervals are plotted successively. At lower right are shown the mass discharges of the ankle extensor evoked by muscle stretch (stretch reflex discharge).

Two cases of idiopathic torsion dystonia, a 14-year male and a 10-year female, were subjected to the V.im. thalamotomy on one side. As illustrated in Fig. 5 , this disorder is characterized by the presence of a specific grouping of discharges ( I 3 to 16 c/s) of involuntary nature on the affected muscles. This grouped discharge of dystonic patients is considered to cause specific dystonic posture of the trunk and girdle musculatures, inverted feet or thalamic posture of fingers. In two cases this was effectively improved by V.im. thalamotomy. And in another two cases the VL and sub-VL thalamotomy had no influence.*

* It is of interest to find similar grouped dischargeof involuntary nature in the experimental animal. Steg observed by administering reserpine the rigidity associated with the grouping (Steg, 1964). Similar EMG grouping discharge (13-15 c/s or more) was observed in extensor limb-muscles of the cat decerebrated at the upper pontine level by the anemic method (a- cat or a-rigidity) (Pollock and Davis, 1930; Granit, 1955). Fig. 6 illustrates at lower right the grouped discharges of one of the ankle extensor muscles of the a-cat which are recorded by a conventional concentric needle and evoked by manual stretching of the muscle at the ankle joint. This fact was confirmed in the extensor-limb muscles of more than 10 a-cats without exception. In a typical case this grouping could easily be felt if fingers are touched upon the muscle belly of the contracting muscles. Although this preparation is familiar to neurophysiologists, as far as authors are aware, the grouping tendency of this‘prepara(continued next page) tion has not yet been’reported.

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DISCUSSION

Division of the thalamic nuclei has been established on various theoretical grounds, that is, on cytoarchitectonic stucture, on anatomical fiber connection and even on the physiological connection with other brain structures. Although the physiological explanation of the mechanism of VL-thalamotomy on the various extrapyramidal disorders is far beyond our reach, one may question whether the VL nucleus is solely destroyed by the VL-thalamotomy. In a case in which the nucleus was claimed to be punctured by the needle, a possibility exists that the actual destructive lesion would have invaded the neighboring structures, such as sub-VL area, V.im. nucleus or even a part of the internal capsule. Vague expressions such as ‘the more posterior part of the VL’, ‘more ventral part of the VL‘, ‘more lateral part of the VL‘ or ‘close to the internal capsule’ are often used without detailed notions of their morphological and physiological features. Using electrical stimulation of the human thalamus, the area was physiologically identified as the VL nucleus, by stimulation of which the augmenting response could effectively be produced on the precentral cortical areas of that side. In good agreement with the human atlases, this area coincides with the anatomically defined VL nucleus. In addition to this, from different manners of the responses of the hand muscle activities by high frequency stimulation, the sub VL area was differentiated from the VL nucleus. Further, a unique positive response evoked by the ulnar nerve stimulation could be recorded from a small area, located posteriorly to the VL nucleus, where, on low frequency stimulation, rhythmic cortical potentials were not noticeable on the EEG, and on high frequency stimulation the tremor was mainly produced and specific sensations were not perceived. The response is conducted by the fibers, whose velocity is faster than the motor fibers to the extrafusal muscle (cf. Hudson and Dow, 1963) and the threshold can be lower than that of motor fibers. In the tibia1 nerve, the group I fibers are excited more sensitively than the motor fibers, reflex response (H reflex or MSR) being more easily evoked than direct response in both humans and cats. Hence it is postulated that the equivalent t o GIa fibers (afferent fibers from the muscle spindles) are likely to be excited and to evoke the positive potential in the area posterior to VL. Recently Oscarsson and Rosen (1963) found the somatosensory representation from the muscle spindle of forelimb muscles which is conveyed to the predimple post-cruciate gyrus via the lemniscus medialis. Their finding is considered to support the above-mentioned findings. This area posterior to the VL seems to lie rostra1 to the posterior group nuclei which receive specific sensation, and is considered as nucleus ventralis intermedius (V.im.) in Bailey-Schaltenbrand’s atlas (1959). Stimulation of this area caused no specific sensation or potentials, which suggests that projection of other sensory inputs are not available. This area also seems to correspond Furthermore, analysis of the spike-to-spike discharge intervals of single neuromuscular unit of the a-rigidity showed a striking difference from those of the y-rigidity. Intervals of the former had more irregular fluctuations and tended t o discharge at shorter intervals than those of the latter (Tokizane and Shimazu, 1964). Two examples of successively plotted discharge intervals from single muscle activities evoked by muscle stretching are illustrated in Fig. 6 ; upper from the y-cat and lower from the a-cat. References p. 349

348

H. N A R A R A Y A S H I A N D K . K U B O T A

to an area, where Albe-Fessard et al. (1963) and Jasper and Bertrand (1964) recorded a rhythmic discharge synchronous with the tremor. These three areas, the VL nucleus, the V.ini. and the sub-VL area seem to have clear differences in functional role in producing extrapyramidal symptoms, such as rigidity, or tremor. The V L is related to the production of muscle hypertonicity and to have much less importance in tremor mechanism. lts stimulation induces muscle discharges non-reciprocally. Its destruction reduces the rigidity, and the effect on the tremor is usually temporary. On the other hand, stimulation of the sub-VL area mostly influences the tremor, though the destruction is quite effective for both rigidity and tremor. The sub-VL area may be coincident with the Fore1 H field, which contains the descending fibers from the pallidum and some tracts from the cerebellar dentate nucleus. The V.im. has an effect in accelerating or inhibiting the parkinsonian tremor without influencing rigidity. A small surgical lesion within this area relieved only the tremor and not the rigidity. Athetosis was neither changed nor alleviated at all by V.im. surgery. Grouped discharges of 13 to 16 c/s similar to the a-rigidity, constituting the main features of the idiopathic and familial torsion dystonia were effectively alleviated by V.im. surgery and not by VL or sub-VL surgery. From these experiences, it seems reasonable to suggest that the pallidal efferent pathway conducting the muscle tone regulation passes the main portion of the sub-VL area flowing into the VL nucleus, and that destruction of any part of this route would alleviate muscle tone disorders (parkinsonian rigidity, or rigido-spasticity in athetosis). Symptomatic torsion dystonia due to perinatal etiology can be treated similarly to perinatal athetosis and is relatively well alleviated by this surgery. Though its physiological meaning is not clear at present, the specific positive responses evoked by the excitation, presumably of fibers of the Group I range of peripheral nerves, were recorded with relatively short latency. This finding suggests that some afferent inflow from muscle spindles might reach the thalamic level, which would very closely correlate to tremor mechanisms. In daily clinical experiences, the tremor i q very easily influenced by giving sensory stimuli to the extremity, such as pinching, touching, muscle stretching, etc. When finger flexors are stretched, tremor can promptly and most effectively be stopped for several tens of seconds. The patient can stop the tremor voluntarily by bending or extending his fingers. A possible interpretation of this effect is that the increased afferent impulses arising from the muscle spindles reach the thalamus at V.im. and influence or modify the tremorous movements. This hypothesis is only intended to indicate a highly possible relation between tremor mechanism and peripheral stimuli. SUMMARY

1. Ventrolateral thalamotomy, widely used for alleviating parkiiisonian rigidity or tremor and other hyperkinetic syndromes, is reconsidered ; and the possibility is suggested that the widely believed effects are essentially due to a lesion within the nucleus itself or to destruction involving neighboring structures. 2. The VL nucleus was regularly found by a physiological method on the operation

R E C O N S I D E R A T I O NO F

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349

table in each case, even in the narcotized state, by recording the rhythmic evoked potentials from the scalp during thalamic stimulation. 3. After the VL nucleus had been physiologically delineated, its lesion reduced parkinsonian rigidity and athetotic rigido-spasticity. 4. The area below the nucleus (sub-VL area) seems to have a closer relation to the tremor mechanism than the VL. 5. The area behind or posterior to the VL (V.im.) appeared t o have no relation to rigidity mechanisms but had a marked influence on the tremorgenic mechanism. Evidence is presented that the affercnt inflow from muscle spindles goes to this area.

REFERENCES R. D., (1959); Depth stimulation and recording i n thalamus ADEY,W. R., RAND,R. W., AND WALTER, and globus pallidus of patients with paralysis agitans. J. nerv. ment. Dis., 129, 417-428. D., ARFEL,G., AND GUIOT,G., (1963); Activites electriques caradristiques de ALBE-FESSARD, quelques structures cerebrdles chez I’honime. Ann. Chir., 17, 1185-1214. COOPER, I. S., A N D BRAVO, G., (1958); Chemopallidectoniy and chemothalamectoniy. J. Neurosurg., 15, 244-250. DEMPSEY, E. W., AND MORRISON, R. S., (1942); Production of rhythmically recurrent cortical potentials after localized thalamic stimulation. Arner. J. Physiol., 135, 293-300. GRANIT,R., (1955); Receptors and Sensory Perception. New Haven, Yale University Press. HASSLER,R., (1959); Introduction to Stereotaxis with Atlas of the Human Brain, G . Schaltenbrand and P. Bailey, Editors. Stuttgart, Thieme; New York, Grune and Stratton. HASSLER, R., AND RIECHERT, T., (1954a); Indikationen und Lokalizationsmethode der gezielten Hirnoperationen. Nervenarzt, 25, 441-447. T., (1954b); Clinical effects produced by stimulations of different HASSLER,R., A N D RIECHERT, thalamic nuclei in humans. Electroenceph. din. Neurophysiol., 6, 5 18-524. HASSLER,R., UND RIECHERT, T., (1961); Wirkungeii der Reizungen und Koagulationen in den Staniniganglien bei stereotaktischen Hirnoperationen. Nervenarzt, 32, 97-109. E. M., AND PURPURA, D. P., (1963); Electrophysiological studies of subcortical relations HOUSEPIAN, in man. Electroenceph. din. Neurophysiol., 15, 20-28. HUDSON,C. H., AND Dow, R. S., (1963); Motor nerve conduction velocity determination. Neurology, 13,982-988. JASPER,H., AND BERTRAND, G., (1964); Exploration of the human thalamus with microelectrodes. Physiologist, 7 , 167. JINNAI,D., A N D NISHIMOTO, A., ( I 963); Stereotaxic destruction of Forel-H for treatment of epilepsy. Neurochirurgiu, 6 , 164- 176. K., HONGO,T., NAGAO,T., A N D NARABAYASHI, H., (1964); Ventrolateral and OHYE,C., KUBOTA, subventrolateral thalamic stimulation, motor effects. Arch. Neurol., 11, 427-434. O., AND ROSEN,I., (1963); Projection to cerebral cortex of large muscle spindle afferents OSCARSSON, in forelimb nerves of the cat. J . Physiol., 169, 924-945. POLLOCK, L. J., AND DAVIS, L., (1930); The reflex activities of a decerebrate animal. J. comp. Neurol., 50, 377-41 I . SCHALTENBRAND, G . ,A N D BAILEY,P., Editors, (1959); Introduction to Stereotaxis with Atlasof Human Brain. Vol. 1-111. New York, Grune and Stratton. SCHLAG, J., A N D BALVIN, R., (1964); Sequence of events following synaptic and electrical excitation of pyramidal neurons of the motor cortex. J . Neurophysiol., 27, 334-366. E. G . , ADAMS,J., FLANAGAN, M., A N D BAIRD,H. W., (1963); SPIEGEL,E. A., WYCIS,H. T., SZEKELY, Campotomy in various extrapyramidal disorders. J . Neurosuvg., 20, 871-884. STEG,G., (1964); Efferent muscle innervation and rigidity. .4cta nhysiol. scand., 61, Suppl. 225. TOKIZANE, T., AND SHJMAZU, H., (1964); Functional Diferentiation o f Human Skeletal Muscle. Tokyo, Tokyo University Press. YOSHIDA,M., YANAGISAWA, N., SHIMAZU, I+., GIvRt, A,, A N D NARABAYASHI, H., (1964); Physiological identification of the thalamic nucleus. Arch. Neurol., 11, 435-443.

350

Sedative Stereoencephalotomy : Fornicotomy, Upper Mesencephalic Reticulotomy and Postero-Medial Hypothalamotomy KEIJI S A N O Department of Neurosurgery, Faculty of Medicine, University of Tokyo, Tokyo (Japan)

Disorders of emotion as manifested in aggressive behavior or attacks of rage are most difficult to handle from medical as well as social points of view. In order to calm or correct such patients, we have performed the operations reported elsewhere; namely, anterior cingulectomy, various thalamotomies, fornicotomy, upper mesencephalic reticulotomy, and posteromedial hypothalamotomy (Sano, 1954, 1960, 1962). The last two procedures and part of the fornicotomy were carried out stereotactically. These three procedures will be discussed here, special emphasis being laid on the posteromedial hypothalamotomy. In attempting these operations with the intention of tranquillizing the patients, one should have in mind a working hypothesis concerning the mechanism of emotion. Our hypothesis is as follows. As is well known, Hess (1947, 1949) divided the diencephalon into two functional sectors, namely, the ergotropic and the trophotropic-endophylactic sectors. In connection with these sectors, there are, we believe, two functional circuits in the prosencephalon as illustrated in Fig. 1, the prosencephalic ergotropic circuit on the right half of the diagram and the prosencephalic trophotropic circuit on the left half of the diagram. The ergotropic zone of the hypothalamus, the anterior thalamic nuclei, the cingulate gyrus and the hippocampus, that is, the circuit roughly corresponding to that proposed by Papez (1937), is comprised in the ergotropic circuit. The trophotropic zone of the hypothalamus including the preoptic area, the posterior orbital area, the insula, the uncus, the amygdala and the other paleocortical areas constitute the trophotropic circuit. The hippocampal formation and the fornix may be regarded as the common axis of these two circuits. The ergotropic and the trophotropic zones of the hypothalamus may be driven not only by neural impulses but by humoral factors, and send impulses to the component areas of the circuits to be concerned with experience of emotion, and at the same time send descending regulatory impulses to the lower structures to play an essential role in the expression of emotion. The integrated function of the ergotropic and the trophotropic circuits is, thus, essential not only in autonomic activities, but i n the experience and expression of emotion. Aggressive behavior or rage can be regarded as unbalanced conditions of the circuits with the dominance of the ergotropic circuit.

S E D A TI V E S T E R E O E N C E P 13 A L O T O M Y

35 1

Fig. 1. Ergotropic and trophotropic circuits in the prosencephalon. Abbr. : Amyg. =: amygdaloid nuclear complex; AN = anterior thalamic nuclei; Corpus Mammill = mammillary bodies; DM = dorsomedial nucleus of the thalamus; Entorhin area = entorhinal area; Ergotropic = ergotropic zone of the hypothalamus; FF == posterior orbital area (area FF); FL = area FL; FLD = fasciculus longitudinalis dorsalis; I A = anterior insula (areaIA); LA = anterior cingulate cortex (area LA); LCZ = posterior cingulate cortex (area LCZ);mammill. Ped. = mammillary peduncle; mammilloteg. Tr. = mammillotegmental tract; MFB = medial forebrain bundle; Pall. = pallidum; Periamyg. = periamygdaloid area; Perif. N. = perifornical nucleus; Periv. F. = periventricularfibers; Post. N. = posterior hypothalamic nucleus; Pre-Opt. = preoptic area; Prepirif. = prepiriform area; Reticular Formation = brain stem reticular formation ; Rhinenceph. = rhinencephalic structures other than described here; Supracall. Str. = supracallosal stria; THT = hypothalamico-tegrnental tract; THN = hypothalamico-nigral tract; TG = temporal pole (area TG); Thal = thalamic nuclei; Trophotropic = trophotropic zone of the hypothalamus; Zona i n e r t . = zona incerta.

Therefore, to calm down the patients, it will be necessary to produce lesions in the ergotropic circuit to normalize the balance. As seen in Fig. 1, overlapping of the two circuits is more marked in the neocortex than in the limbic cortex, and in the limbic cortex more than in the diencephalon. So, lesions made in the area of higher order will produce less marked and less lasting effects than lesions in the area of lower order. In this sense, lesions in the hypothalamus should produce the most pronounced and most continuing effects. At first, however, we were afraid that surgical interference with the hypothalamus References p . 3711372

352

K. S A N O

might cause such serious autonomic and endocrine disturbances as to endanger life. This is why we made, so to speak, a detour until finally we attempted the hypothalamotomy. After we had found the long-term results of the anterior cingulectomy and the thalamotomies not altogether satisfrzctory (Sano, I962), we tried fornicotoniy and upper mesencephalic reticulotomy. I . Fornicotomy

The fornix is one of the most obvious connections between the temporal lobe and the diencephalo-mesencephalon, including the efferent fibers from the hippocampus and the afferent fibers to the hippocampus which arise mainly from the septal area. The former fibers are reported to go to the mammillary bodies, the other hypothalamic areas (nucleus perifornicalis, ventromedial nucleus, dorsomedial nucleus, paraventricular nucleus, anterior hypothalamus and preoptic area etc.), the septal area, the habenular nucleus, the rostra1 midbrain (the limbic midbrain area(Nauta, 1958)) and the opposite hippocampus. Thus the fornix and the hippocampus send fibers to both the ergotropic and the trophotropic circuits, and constitute the common axis of these circuits. The fornix sends fibers to the perifornical nucleus (Jo, 1960; Sprague and Meyer, 1950) which is the very area in which Hess (1947, 1949) obtained most pronounced rage reaction upon its stimulation. Hence, section of the fornix will not only decrease the 'tonus' of the circuits, but also reduce the impulses to that nucleus, and may well result in sedative effects. Section of the fornix has been tried in several conditions; by Umbach (1954) for psychomotor seizures, by Bengochea et al. (1956) for generalized convulsive seizures, and incidentally at operations on tumors in the third ventricle by several surgeons. In these reports one finds no detailed account of emotional changes. In animal experiments, however, calming effects have been obtained by section or electrocoagulation of the fornix (Simpson, 1952; Bond et a/., 1957). We performed fornicotomy, first by transcallosal approach on 14 cases as reported elsewhere (Sano, 1962), later by stereotaxic means on 7 cases. In the former, the fornix was cut with a hooked knife, and in the latter it was electrocauterized, both bilaterally, just above or behind the foramina of Monro. Of these two procedures the transcallosal fornicotomy seemed to be more effective than the stereotaxic one, but its surgical risk is far greater. Two deaths in Table I (one was due to ileus) belonged to the transcallosal group. Postoperative changes were as follows. (1) Emotional and personality changes. Patients became calm, placid, tractable and of decreased spontaneity. These effects are of therapeutic significance. (2) Disturbance of recent memory or memorizing. This was especially marked during 1 month after the procedure, gradually subsiding after that. This is a disadvantage of the procedure. As seen in Table I, fornicotomy was effective mostly in epileptic personality changes, that is, irritability and aggressive behavior developed in the course of repeated convulsive seizures. In these cases, irritative foci were probably formed in the temporal lobe, especially in the hippocampal region, as the result of seizures, and these foci may

353

SEDATIVE STEREOENCEPHALOTOMY

TABLE I

21 cases (3 years 8 months-8 years 8 months) FORNICOTOMY

Cases

Eflecrive

Not eflective

Op. dearh

Psychomotor seizure Convulsive j- psychomotor seizure psychomotor seizure t rage attacks Convulsive Convulsive seizure I rage attacks Agitated idiocy Agitated idiocy with convulsive seizure Violent behavior Schizophrenia

+

have bombarded the hypothalamus through the fornix. Section of the fornix will prevent this bombardment. In a similar sense, fornicotomy will be effective for psychomotor seizures with bilateral temporal lobe foci. In the follow-up of this procedure, calming effects were noted in about 71 ”/, of the cases. 11. Upper mesencephalic reticulotomy

It is well known that the brain stem reticular system exerts various influences on all aspects of nervous activity by its ascending and descending projections. It is easily conceivable that the ‘tonus’ of the cerebral cortex may change, and aggressive behavior will be altered if a lesion be produced in a certain site of the reticular system. As such a site, the most rostra1 part of the mesencephalic reticular formation around the aqueduct was chosen, because this area is apart from the motor and specific sensory pathways and the oculomotor nuclei, and furthermore this area belongs to the limbic midbrain area of Nauta (Nauta, 1958), a lesion of which will influence the limbic system.

AJ

I0

+

Fig. 2. Upper mesencephalic reticulotomy. CC = cerebral peduncle; LM ST = medial lemniscus and spinothalamic tract; N R =- red nucleus; SN = substantia nigra; Stippled area == the site of lesion. Rrfrri.nics p . 3711372

T A B L E I1 UPPER MESENCEPHALIC RETICULOTOMY

Cases

Age

Disease

Sex

Operation

Period of observation

Results

-

1

K.S.

31

m

Epilepsy with violent behavior

2

H.O.

5

m

3

T.S.

8

m

4

H.I.

26

f

5

M.I.

7

f

6

H.S.

4

f

Epilepsy with violent behavior, idiocy Epilepsy, mental defective with violent behavior psychoEpilepsy (convulsive motor) with violent behavior Epilepsy with hemiplegia, irritable Infantile autism with stereotyped movement

-

~

+

Reticulotomy Fornicotomy + Amygdalohippocampotom y Reticulotomy

4Y

8m

Calm No seizure

4Y

4m

Nochange

Ret iculotomy

4Y

1m

Reticulotomy

4Y

1m

Ret iculotomy

3Y

11 m

3Y

11 m

Slightly cainied No seizure Calm Seizure persistent Slightly calmed Seizure persistent Slightly improved

+

Reticulotomy Thalamotom y

S E D A T l V E STEREOENCEPHALOTOMY

355

The dorsal longitudinal fasciculus of Schiitz runs in the periaqueductal gray matter and will be damaged by a lesion in this area. Therefore, at least apart ofthe sympathetic outflows will be blocked by the lesion: the hypothalamico-tegmental and the hypothalamico-nigral tracts, however, will be preserved (Ban, 1964). We named this procedure upper mesencephalic reticulotomy and have reported the details elsewhere (Sano, 1960). A needle, 0.8 mm in diameter, insulated except for its tip, was inserted into this area by stereotactic means under X-ray control. The proposed area was easily identified, as the rostra1 part of the aqueduct was visible in the pneumoencephalogram. Electrocoagulation of the area was performed by means of direct current (10 V, 3-3.5 mA, 60 to 90 sec) with the needle tip as the cathode. The lesion was estimated to be 3 to 5 mm in diameter (the area stippled in Fig. 2), involving the periaqueductal gray matter and the surrounding reticular formation. In this lesion, the only structure that might cause untoward phenomena is the subcommissural organ, injury of which will produce disturbances of water metabolism. In our series, one case showed temporary dehydration after the operation and was relieved by infusion.

Fig. 3. Responses upon stimu1ation”ofthe ergotropic zone of the hypothalamus. P.R. = pulse1rate; B.P. = blood pressure; Stim. -celectrical stimulation; Electrocoagul. = electrocoagulation.

Fig. 4. Ergotropic triangle. References p . 3711372

356

K. SANO

Fig. 5. Posteroniedial hypothalarnotomy. See text for dctails.

SEDATIVE STEREOENCEPHALOTOMY

Fig. 5B. For legend see p. 356.

Referrncrs p . 3711372

357

358

K. S A N O

Table TI summarizes 6 cases that underwent this procedure. Tendency to calmness was noted in 4 cases, but this was not so marked as expected. The operation seemed to exert a favorable influence upon seizures originating in the neocortex and an unfavorable one upon seizures with foci in the limbic system. Most marked changes occurred in EEG. All cases showed slow waves in scalp EEG postoperativeIy. This slowing was long-lasting, even more than 2 years. The consciousness, however, was not impaired, and when external stimuli were applied, desynchronization of EEG occurred promptly in all leads. The sleep EEG was practically normal. Probably thelesion was so small that consciousness, the gross indicator of cerebral function, did not show anpreciable changes, while EEG, the fine indicator of the function, exhibited slowing. I l l . Portercmedial hypothalamotomy

The results of the above-mentioned procedures were far from satisfactory. This urged us to make a lesion in the ergotropic zone of the hypothalamus which may be regarded as the central station of the ergotropic circuits. According to Beattie (1930, 1932), Hess (1947, 1949) and others, the posterior part of the hypothalarnua, that is, the area posterior roughly to the level of the mammillary body, is ergotropic. On the other hand, Kurotsu (1949, 1954) described three zones in the animal hypothalamus ;namely, from medial to lateral, the parasympathetic a-zone, the sympathetic b-zone and the parasympathetic c-zone. The b-zone covers the area from 1 to 5 mm lateral to the wall of the third ventricle. Since the lateral hypothalamic area (the c-zone of Kurotsu) is known to play an important role in temperature regulation and in food and water intake, me planned to make a lesion in the posteromedial part of the hypothalamus, namely, the posterior part of the b-zone. First, our target was the posterior portion of the posterior hypothalamic nucleus. This nucleus is known to be sympathetic and to send and receive fibers of the dorsal longitudinal fasciculus of Schiitz (Ban, 1962) and is continuous with the perifornical nucleus where rage reactions were most easily obtained upon stimulation in the experiments of Hess on cats. Care was taken not to damage the ventromedial nucleus in front of this nucleus, since destruction of the ventromedial nucleus was proved to make the animal ferocious in Wheatley’s experiment (Wheatley, 1944). The posterior portion of the posterior hypothalamic nucleus is located, in the lateral view of the pneumoencephalogram, 1 mm anterior to and 3-4 mm inferior to the midpoint of the intercommissural line. Tn the antero-posterior view, this target point should be located from 1 to 3 mm lateral to the wall of the third ventricle. A needle was inserted into this area stereotactically. When the needle tip was confirmed to be situated in the proper position, general anesthesia was lightened and the patient was immobilized by succinylcholine chloride. Electrical stimulation of the area was performed with a concentric bipolar needle electrode, 0.8 mm in outer diameter, using square pulse waves, 10-30 V, 100-300 cjs, 1-0.3 msec, for 10-20 sec (in the first 6 cases, we used monopolar stimulation with the reference on the ipsilateral shoulder, as reported elsewhere (Sano, 1962)). As seen in Fig. 3, marked rise in blood pressure, tachycardia, maximal pupillodilatation, and

SEDATIVE STEREOENCEPHALOTOMY

359

sometimes flushing of the face were noted upon stimulation. Unilateral stimulation elicited bilateral responses. Pupillodilatation, however, was sometimes more marked on the ipsilateral, and sometimes more marked on the contralateral side. After cessation of stimulation these changes gradually subsided in about 2 min. Such an area as showed most marked signs of sympathetic discharge upon stimulation was electrocauterized by direct current, 15 V, 3-5 mA, first bipolarly for 2 min, then monopolarly for 2 min with the needle tip as the cathode and the reference on the ipsilateral shoulder. The lesion produced was estimated to be 5-5.5 mm in diameter. The procedure was performed bilaterally with an interval of 7-20 days, usually 7 days. Marked calming effects were noted after the bilateral procedure. Such an area, where stimulation consistently elicits signs of sympathetic discharge and electrocauterization produces calming effects, is by no means restricted to the posterior part of the posterior hypothalamic nucleus. It is diffusely distributed in a zone. In the lateral view, it is located in a triangle formed by the midpoint of the intercommissural line, the anterior border of the mammillary body and the rostra1 end of the aqueduct, as illustrated in Fig. 4. And, in the antero-posterior view, it is located from 1 to 3 mm lateral to the lateral wall of the third ventricle. This triangular zone is the ergotropic zone of the human hypothalamus, and may be called the ‘ergotropic triangle’. Fig. 5 (A and B) is an example with a needle stereotactically placed in this triangle. Implanted electrodes in various areas can also be seen. When the needle was inserted into areas other than this triangle, for instance an area more than 5 mm lateral to the lateral wall of the third ventricle or the anterior part of the hypothalamus, electrical stimulation of the area with the same parameters most often yielded parasympathetic responses such as pupilloconstriction, fall in blood pressure and bradycardia, or sometimes no response at all. During these operations, electrographic changes were recorded by means of the needle inserted into the posteromedial hypothalamus and implanted electrodes in other areas, such as the hippocampus, the amygdala, the temporal and the frontal cortices, the anterior hypothalamus and the thalamus. Fig. 6 shows high frequency (300 cis, 0.3 msec) stimulation of the ergotropic triangle. The hippocampus exhibited desynchronization as seen in the upper trace. With higher voltage, however, this showed 6 cjs wave bursts as seen in the lower trace. Other leads, including that of the amygdala, exhibited low voltage faster waves on stimulation. This desynchronization was more marked in the limbic system structures than in the neocortex. By stimulation of the hippocampus, desynchronization appeared in the amygdala. Practically no change, however, was noted in other leads including that of the posteromedial hypothalamus. Upon stimulation of the amygdala, the hippocampus and the temporal pole showed desynchronization. No change was noted in other leads. Stimulation of the temporal pole resulted in an increase in fast waves in the hippocampus and the amygdala and in an increase in amplitude in the frontal cortex and the posteromedial hypothalamus. Seizure discharges in the amygdala, the temporal pole and the hippocampus were stopped by stimulation of the posteromedial hypothalamus (Fig. 7). All these EEG findings suggest some connections between these structures. Refcrcnces p . 3 7 1 / 3 i Z

w b\

0

L. v s t . Hypothalamus

300 e/s. 0 . 3 msec, 2 0 V

2

0

. ---

& ---* -

35 Y

L

I sec

sop

Fig. 6. H.N. 37-year-old male. Epilepsy and rage. Stimulation of the posteromedial hypothalamus, AMG or AMY = mygdaloid nuclei; F = frontal (scalp); HIP - hippocampus; inf. Rol =inferior rolandic area; L. left; M.F = middle frontal area; p.HT = posteromedial hypothalamus; T.P = temporal pole. The same abbreviations are used jn Figs. 6, 7, 8, 9 and 10. 7

L..post. Hypothalamus

300 c/s, 0.3rnsec, 3 . 5 V

Fig. 7. The same case as in Fig. 6 . Stimulation of the posteromedial hypothalamus.

362

K. S A N O rlyht

.\>ll;*’l’I ’

I

T I’+HI I’

I

SO#\

50lll.W

Fig. 8. H.U. 21-year-old male. Epilepsy, mental retardation and attacks of rage. Evoked potentials, stimulation: 15 V, 10 msec.

In order to study the fiber connections more exactly, we recorded evoked potentials caused by low frequency stimulation of these structures. Fig. 8 shows superimpositions of the evoked potentials obtained i n the structures to the right of the arrows upon stimulation ofthose to the left of the arrows. From these we conclude as follows: there are two-way connections between two respectively of the hippocampus, the amygdala and the temporal pole. There are projections from the hippocampus and from the amygdala to the posteromedial hypothalamus, but reverse projections directly from the latter cannot always be confirmed by this method (Sano, 1964). After electrocoagulation, the posteromedial hypothalamus showed only a flat line as seen in Fig. 9. Slower waves appeared in the hippocampus, the amygdala and the temporal pole, but the frontal neocortex showed only little change. Fig. 10 is an electrogram also after electrocoagulation of the posteromedial hypothalamus. The cauterized area showed only a flat line, while in the hippocampus, 2.5 cjs regular slow

363

SEDATIVE STEREOENCEPHALOTOMY

A

Before coagulation HIP

~

~

B

After

*

,

-

.

c

:

I t

4,

r:

.,

:

!

-

I

lsec 50pV Fig. 9. The same case as in Figs. 6 and 7. Before and after electrocoagulation of the posteromedial hypothalamus.

waves appeared for some minutes. This is possibly because the hippocampus was activated by D.C. stimulation in the hypothalamus. These results are suggestive of fiber projections from the posteromedial hypothalamus to the hippocampus, even if they are not direct. There were two groups in post-operstive scalp EEG. One showed no marked changes. The other showed marked slowing of EEG after the operation. This slowing, however, was not so long-lasting as in lesions of the mesencephalic reticular formation.Theslowing was probably due to injury of the fibers from the hypothalamus to the reticular formation. There was no appreciable difference in sedative effects between these two groups with and without slowing of EEG. Post-operative changes were as follows. (1) Emotional and personality changes. The patients became markedly calm, passive and tractable, showing decreased spontaneity. These changes were long-lasting, References p . 3711372

364

K. S A N O

1

u.HT --

-

2 L.HIP

4 L.p.AMG

w 5 L. i n € . Rol

1 2-3

Fig. 10. N.I. 12-year-old male. Epilepsy, idiocy, violent behavior. Immediately after electrocoagu-

lation of the posteromedial hypothalamus.

although spontaneity recovered to a considerable extent in I month. Sometimes somnolence was noted for the first 7 to 10 days. It is interesting to note that the ergotropic triangle corresponds roughly to the area where Von Economo (1918), Nauta (1946), Thompson (1951) and others assumed the waking center to be located. The reason why somnolence is only temporary is probably that the lesion is too small and that the area projects mostly to the limbic system and only to a small extent to the neocortex. Tntelligence was not impaired by this posteromedial hypothalamotomy. Amelioration of the intelligence quotient was often noted after the operation. This may be because the patients became cooperative after this stereoencephalotomy. (2) Effects on autonomic and endocrine activities. Post-operatively there was a tendency to a decrease in sympathicotonia or an increase i n parasympathicotonia. Measurement of catecholamine in the urine showed that excretion of epinephrine increased temporarily after the operation. Sometimes goose flesh and dermographism were noted for several days post-operatively, Fig. 1I is an example. This case was slightly sympathicotonic before operation and

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became of normal autonomic balance post-operatively as shown by the Mecholyl test. He had also shown marked vasoconstrictor responses to any kind of stress, but these responses decreased in amplitude and in duration after the operation. (3) Catalepsy. In some cases, temporary catalepsy, lasting only for several days, was noted after the operation. (4) Changes of eye movements. When a patient showed convergence of eye-balls upon stimulation of the ergotropic triangle, he sometimes exhibited slight divergent strabismus temporarily after operation. In some cases, after unilateral operation, coordination of both eye-balls seemed to be disturbed, but this disturbance completely disappeared after the bilateral operation. Pupils usually became miotic temporarily after the procedure. (5) Changes of EEG. These are already stated. Thus, continuous post-operative changes are those of personality and emotion, and others are only temporary. Table 111 is a summary of 13 of our cases. The calming effects were more pronounced and more continuing than those produced by any other procedures we have tried. In one case (K.O.), violent behavior recurred 3 months post-operatively, but References p.'371/372

366

K. S A N O

Fig. 12. The same case as in Fig. 11. Note marked atrophy of the right cerebral hemisphere. Posteromedial hypothalamotomy on the left side.

SEDATIVE STEREOENCEPHALOTOMY

Fig. 126. For legend see p. 366.

References p . 371/372

367

K. S A N O TA BLE TI1 POSTEROMEDIAL HYPOTHALAMOTOMY

Age

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24

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Cases

Period of observation

Epilepsy, idiocy, rage attacks Epilepsy, mental retardation, rage attacks Epilepsy, mental retardation, rage attacks Epilepsy, idiocy, violent behavior Epilepsy, mental retardation, rage attacks Mental retardation, epilepsy, violent behavior Epilepsy, mental retardation, rage attacks Epilepsy, rage attacks Epilepsy, mental retardation, violent behavior Epilepsy, rage attacks, mental retardation Epilepsy, idiocy, violent behavior, tuberous sclerosis Epilepsy, rage attacks, mental retardation Epilepsy, violent behavior

Results

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re-operation produced good results, The 9th case (T.M.) in the Table is cerebral palsy with marked hemiatrophy of the right cerebral hemisphere, showing mental retardation and intractable convulsive seizures (Fig. 12 A and B). Such a case used to be a good indication of cerebral hemispherectomy. In this case, however, we performed the posteromedial hypothalamotomy only on the normal (left) side, with marked sedative effects. Even seizures became controllable by medication. Probably only the hypothalamus on the normal side was functioning. It seems that many of the candidates for cerebral hemispherectomy will be relieved by this simple procedure. Stimulation and destruction qf the h y ~ o t ~ a l a in ~ ucats s Tn order to elucidate finer hypothalamic mechanisms and to confirm our balance

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w o\

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370

K. S A N O

theory of emotion, we have done animal experiments. The results of experiments on cats are summarized as follows. High frequency stimulation (100-300 c/s, 0.2-0.3 msec) of the posteromedial hypothalamus by means of chronically implanted electrodes awakened a sleeping cat, provoking regular slow waves in the hippocampus, as seen in the upper traces (A) of Fig. 13. Repeated stimulation, or stimulation with higher voltage, of the same structure produced rage like behavior, as imagined by moving artifacts in the middle traces (Bl; the behavior was always accompanied by regular slow waves in the hippocampus. High frequency stimulation of the preoptic area calmed down the rage-like behavior, when the stimulation was strong enough to extinguish the hippocampal regular :low waves, as seen i n the lower traces (C). Not only the preoptic area, but any structures in the trophotropic circuit can control this rage-like behavior, if stronger stimulation be applied, strong enough to extinguish the hippocampal regular slow waves. Bilateral or even unilateral destruction of the posteromedial hypothalamus showed calming effects. Such destruction, however, should be large enough to extinguish the regular slow waves of the bilateral or ipsilateral hippocampus. Lf the lesion was too large, the cat became stuporous and anorexic and died in a few weeks. Unilateral destruction of the preoptic area did not cause appreciable changes in behavior. This is probably because the preoptic area on the opposite side and other trophotropic areas can still control the ergotropic zone. The regular slow waves of the hippocampus, however, became unable to be evoked on the side of lesion. This can be explained by the anatomical data that the pathways concerned with eliciting the regular slow waves of the hippocampus run through the preoptic area and reach the septa1 nuclei to be relayed t o the fornix fibers. Thus, the hippocampal regular slow waves per se are not important in mechanisms of emotion; they can, however, be used as a good indicator of the level of excitation of the posteromedial hypothalamus. Bilateral destruction of the preoptic area causes cats to be extremely ferocious and violent, until finally they became exhausted and died. Fig. 14 shows EEG of such a cat in the waking stage. Hyperactivity is demonstrated by moving artifacts. The hippocampus does not exhibit regular slow waves, but the other leads all show waking patterns. I V . Summary and conclusion

(I) A working hypothesis is proposed. There are two functional circuits in the prosencephalon: the prosencephalic ergotropic circuit and the prosencephalic trophotropic circuit. The integrated function of these two circuits is essential not only in autonomic activities, but in experience and expression of emotion. An unbalanced condition of the circuits with the dominance of the ergotropic circuit causes aggressive behavior or rage. In order to calm down the patient, it is necessary to produce lesions in the ergotropic circuit to normalize the balance. (2) Based on this theory of balance oftwo circuits, the author has performed various sedative operations including fornicotomy, upper mesencephalic reticulotomy and posteromedial hypothalamotomy, and eventually found that the last procedure,

371

SEDATIVE STEREOENCEPHALOTOMY

1 sec

I O P

Fig. 14. Cat. After destruction of the bilateral preoptic area

namely, stereotaxic lesion of the ergotropic zone of the hypothalamus, produced most marked sedative effects and less side effects. (3) The results of experiments on the hypothalamus in cats are briefly stated and discussed. ( 4 ) Emotion is a fundamental activity closely connected with our existence, just as the autonomic activities are. It is quite understandable that the hypothalamus, as it were the central station of the autonomic activities where many fibers come in and go out, is at the same time the central station of emotion. It is hoped that finer construction and more minute mechanisms of this central station will be elucidated in the near future. REFERENCES

BAN, T., (1962); Morphological aspects of the hypothalamus (Japanese). Rec. Advun. Res. new. S.~sr., 6,837-872. BAN,T., (1964); Experimental studies on behavioral mechanism of the hypothalamus (Japanese). Brain, Nerve, 16, 824-827.

372

K. S A N O

BEATTIE,J., (1932); Hypothalamic mechanisms. Canad. med. Ass. J . , 26, 400-405. BEATTIE, J., BROW,C. R., A N D LONG,C. N. H., (1930); Physiological and anatomical evidence for the existence of nerve tracts connecting the hypothalamus with spinal sympathetic centres. Proc. roy. Soc., Ser. B., 106, 253-275. BENGOCHEA, F. G . ,DELATORRE, o.,ESQUIVEL, o.,VICrA, R.,AND FERNANDEZ,J. c.,(1956); Section of the fornix in surgical treatment of certain epilepsies. Acraneurol. la/.-amer., 2, 153-158. Cited in Yearbook Neurol. psychiat. Neurosurg., 1956-1 957, pp. 550. BOND,D. D., RANDT,C. T., BIDDER, T. G., AND KOWLAND,V., (1957); Posterior septal, fornical, and anterior thalamic lesions in the cat. Vegetative and behavioral changes with anatomical and physiological correlations. Arch. Neurol. Psychiat. (Chic.),78, 143-1 62. HESS,W. R., (1947); Vegetative Funktionen und Zwischenhirn. Helv. physiol. phaumacol. Acta, Suppl. IV. Htss, W. R., (1949); Das Zwischenhirn. Syndrome, Lokalisationen, Funkrionen. Basel, Schwabe &. Co. Jo, K . , (1960); Fiber connections of the rhinencephalon (Japanese). Kaibogaku-Zasshi, 35, 735-769. KUROTSU,T., (1949); On autonomic center (Japanese). No-Kenkyu, 3, 39-56. KUROTSU, T., (1954); Changes of fincr structures of different gland cells induced by the electrical stimulation of the hypothalamus. Merl. J . Osaka Univ., 5, 87-104. NAWTA,W. J. H., (1946); Hypothalamic regulation of slecp in rats. An experimental study. J . Neurophysiol., 9, 285-3 16. NAUTA,W. J . H., (1958); Hippocampal projections and related neural pathways to the mid-brain in the cat. Brain, 81,319-340. PAPEZ,J . W., (1937); A proposed mechanism of emotion. Arch. Neurol. Psychiat. (Chic.), 38, 725143. SANO,K., (1954); Cingulectomy in thc trcatinent of agitated mental defectives. Brain, Nerve, 6, 146-1 56. SANO,K., (I 960); Upper mesencephalic reticulotomy i n epilepsy and behavior disorders. Niwrul. med-chir., 2, 138-146. SANO,K., (1962); Sedative neurosurgery, with special reference to postero-medial hypothalamotorny. Neurol. w i d - c h i r . , 4, I 12-142. SANO,K., (1964); Neurosurgical considerations of the hypothalamic mechanism of emotion (Japanese). Brain, Nerve, 16,815-824. SIMPSON, D. A., (1952); The efferent fibers of the hippocampus in the monkey. 1.Neurol. Neurosurg. Psychiat., 15, 79-92. SPRAGUE, J. M . , A N D MEYER, M., (1950); An experimental study of the fornix in the rabbit. J . Anat. (Lond.), 84, 354-368. THOMPSON, G . N . , (1951); Cerebral area essential to consciousness. Bull. Los Angeles netrrol. Soc., 16, 311-334. UMHACH, W., (1954); Fornicotoniie zur Behandlung der Temporallappen-EpileFsie. DtscA. A m w . Neurochir. Sytnpos., Freiburg. VONE C O N O MC., ~ , (1918); Die Encephalitis Lethargica. Wien, Deutcke. WHEATLEY, M. D., (1944); The hypothalamus and affective behavior in cats. Arch. Neurol. Psychiat. (Chic.), 52, 296-3 16.

373

Clinico - Pathological and Histochemical Studies of Hallervorden-Spatz Disease with Torsion Dystonia with Special Reference to Diagnostic Criteria of the Disease from the Clinico - Pathological Viewpoint N O B U O Y A N A G I S A W A, HI ROTS U G U SHIRAKI, MASAO M I N A K A W A A N D HIROTARO N A R A B A Y A S H I Department of Neuropathology, Institute of Brain Research, Faculty of Medicine, University of Tokyo, Tokyo (Japan), Moro Mental Hospital, Moro, Saitama (Japan), and Department of Neurology, School of Medicine, Juntendo University, Tokyo (Japan)

INTRODUCTION

Hallervorden-Spatz disease or syndrome is a rare clinico-pathological condition which affects hitherto normally developing children around 10 years of age who are then doomed to death after a clinical course of 10 to 20 years. Stiffness ofthe extremities and mental retardation of a progressive nature, and the not infrequent familial incidence of the. disease, constitute the main clinico-epidemiological features. Hyperkinetic states, such)s choreo-athetosis, dystonia etc., have occasionally been reported. The main sites of the lesions are the globus pallidus and the reticular zone of the substantia nigra where an enormous number of deposits of pigmentary granules and pseudocalcareous concretions are found. A rust-brownish discoloration of both nuclei is easily recognized even on gross examination. Another characteristic change is the presence of spheroid structures which are now commonly accepted as being derived from axonal dystrophy or degeneration. The spheroids were widespread in different areas of the central nervous system in the original case reported by Hallervorden and Spatz (1 922), but they frequently appeared predominant in the above-mentioned two nuclei. However, several authors have paid little attention to this finding (Funfgeld, 1930; Winkelman, 1932; Benda, 1949; Netzky et al., 1951; Zeman and Scarpelli, 1958). In 1957 Seitelberger and his associates emphasized the view that the presence of spheroid structures (Schollen-Substanzen) should be considered pathognomonic for Hallervorden-Spatz disease. Based upon a detailed hstochemical analysis, they claimed a common pathogenesis for this condition and infantile neuraxonal proteid dystrophy without increased pigmentary deposition. Zeman and Scarpelli (1 958), on the other hand, analysed the histochemical properties of so-called ‘non-specific’ lipid accumulation in ganglion cells of the cortex and other parts of the gray matter and References p. 423425

374

N. Y A N A G I S A W A

et al.

proposed that the disturbed lipid metabolism was analogous to that found in the cerebral lipidoses. The present report concerns two siblings in whom the neuropathological features corresponded well with the classical criteria of Hallervorden-Spatz disease, while the clinical pictures consisted of typical torsion dystonia the nature of which was analyzed by electromyography. Furthermore, in Case 1 destruction of both the thalamic nuclei and the globus pallidi was performed bilaterally by stereotaxic neurosurgery. The histochemical analysis was concurrently done to clarify the nature of the increased pigmentary granules, the spheroid structures and the widespread lipid accumulation in neuronal cells.

C A S E REPORTS

Case I ( A ) Clinical jeatures (Figs. I and 2) Past and family histories. Patient M. H., a n 18-year-old female, was admitted to the local mental hospital, Moro, in the suburbs of Tokyo, on 30 August 1959, because of progressive stiffness and involuntary movements of both extremities and trunk. Birth weight had been 3200 g, and delivery had been normal. She began to walk at I year and 4 months, and developed normally, physically and mentally, until 12 years of age. At that time she became retarded in her school work, and her scholastic record was very poor at the end of junior high school. She also became dull, untidy and irritable. During the next year involuntary twistings and incoordinated movements of the left hand, and then of the right became manifest. In the subsequent several months she began to stumble. The bizarre twistings of the upper extremities while the patient walked, or when she intended to grasp something, became more and more pronounced, and the legs stiffened. At 17 years of age she developed torticollis and was almost unable to stand without support. The psychic condition remained stationary throughout this period. She was the eldest of three siblings. A younger sister, Case 2 K. H., who will be described in detail, suffered from the same illness. The brother aged 15, and the parents without a history of consanguineous marriage, showed no neurological or psychic abnormalities. As far as examined, no neurological or psychotic disorders were present in the rest of the family. Status on admission. The patient had an apathetic face and was emaciated. At times she developed a characteristic posture of an involuntary nature which can be described as follows (Figs. 2A-F). The neck was bent to the left and backwards, and the trunk extended at the thoracic spine (opisthotonus). The face grimaced, the mouth half opened, and protrusion of the tongue was impossible. The left arm extended backwards at the shoulder and elbow joints with the forearm overpronated, the fingers flexed moderately at each phalangeal joint, and sometimes the thumb strongly adducted. The right arm mostly stretched forwards and inwards at the shoulder and extended at the elbow, flexed wrist and phalangeal joints with moderate pronation of the fore-

HALLERVORDEN-SPATZ DISEASE

375

arm. Sometimes the right arm was flexed at the elbow, over-extended at the wrist joint and pronated. The thigh was usually not involved but sometimes flexed. The feet were inverted and plantar-flexed (pes equinus). The patient suffered from these dystonic attacks frequently throughout the day, each of them lasting for 10 to 30 sec. These dystonic movements were analyzed with electromyograms which will be described later. The pupils were round and equal, and responded to light promptly. Speech was sluggish and dysarthric. The extremities became stiff when touched by the examiner and there was a fluctuating resistance to repeated passive movements. Voluntary movements of the fingers were severely restricted. She could not open or close her fists, and dysdiadochokinesis was marked. The knee and ankle extensor muscles were moderately rigidospastic, but the involuntary movement or fluctuation of muscle tone were much less marked than in the upper extremities. The patellar and Achilles tendon reflexes were exaggerated, while Babinski’s sign was present bilaterally. She was well-oriented to time and place. She knew the name of the hospital and was able to state the year, month, day of the week and the time of day. She could recall the year of her graduation and of the onset of her disease. Ophthalmoscopic examination revealed pigmentary degeneration of the retina ; the disc was slightly reddish, but its edge was well defined and showed no turbidity. In the fundi variously-shaped, tiny pigmentary spots with whitish patches were disseminated, and predominated peripherally. Surprisingly, nyctalopia or other visual disturbances were never complained of, although detailed examinations of visual acuity and fields could not be obtained at this late stage of the illness. N o abnormal results of the routine examinations of blood and cerebrospinal fluid including Wassermann reaction were obtained. The urine analysis as well as X-ray examination of the skull were normal. Course ofillness. The motor disturbances progressed slowly with certain spontaneous remissions as seen in Fig. 1. Chlorpromazine, in particular, had occasional transient effects in improving the physical condition of the patient so that she could stand and walk without support. In walking marked clubfoot was noted especially on the left side. Romberg’s sign was negative. Spontaneous speech was almost absent even in her best condition. From 14 to 28 November 1959, stereotaxic neurosurgery was performed at the Neurological Clinic by Dr. H. Narabayashi. The globus pallidi on both sides and the ventrolateral thalamic nucleus on the left side were located, and 0.5 to 0.8 ml of olive oil and bees-wax mixtures were injected into each locus. Subsequently, speech became somewhat clearer, and the dystonic movements seemed to diminish to a slight degree,but the effects were transient and other motor disturbances remained essentially unchanged. From April to July 1960 the patient was at home, and suffered considerably from frequent attacks of both dystonic movements and posture. At the time of readmission in July 1960 she was very emaciated. The dystonic movements and postures still occurred frequently, but the rigidospasticity of the extremities was only slight. She could respond to and enjoyed the visit of her family, but there was a certain deterioration of general knowledge, ability to count and judgement. She could not References p . 4 2 3 4 2 5

316 N. Y A N A G I S A W A

+ +I =

i f -

et al.

+I

Fig. 2. Serial photographic representations of dystonic movements of Case 1 (20-year-old female) sitting on the chair. The speed of filming was at 16 frames per sec. (A) Several seconds after the onset of a dystonic attack, the head is bent backwards, the left arm pulled straight forward, and then moved laterally backwards with stretched-out arm on the right. (B) 3 sec after (A). The flexion of the head and the facial grimacing are more pronounced. The left arm is gradually returned to the front with extension at both wrist and phalangeal joints. ( C ) 7 sec after (A). The right arm is sustained in a pronated position; the left arm is in moderate pronation and the fingers again extend laterally. (D) 10 sec after (A). The patient is now free of the involuntary movements of both head and left arm, while the pronated right arm extends backwards. (E) 14 sec after (A). The head again is bent backwards and the right thigh flexed at the hip joint. The pes equinus, whichconstitutesaconstant stigma independent of the dystonic movements, can be seen. (F) 18 sec after (A). The patient is now completely relaxed and remains calm for a few minutes. References p . 423-425

378

N . Y A N A G I S A W A el U l .

give information about famous persons or major events in the past. She had considerable difficulty in solving problems using two-digit numbers. She could not explain correctly the meaning of some common proverbs. From the beginning of 1961 she became obese and frequently had high fever and recurrent abdominal pains combined with diarrhea when the dystonic movements diminished. On 17 December 1961 a right ventrolateral thalamotomy was carried out at the Neurological Clinic. This had no particular effect on the dystonic movements. Subsequently, the impairment of speech progressed severely, and she could no longer answer any questions. Yet she was never indifferent to her environment, and could, more or less, respond to doctors, nurses and her family. From early in 1963 she was bedridden, could not chew or swallow food, and developed complete incontinence. The dystonic movements became less frequent, but the abnormal postures with both torticollis and pes equinus persisted. In this stage, voluntary movement became almost impossible, in part due to distinct muscular weakness. Decubiti with severe pain developed on her back at the bony prominences of both shoulder and ilium, and sleep was considerably disturbed. On 10 June 1963, at the age of 22, she expired from aspiration pneumonia. The total duration of the illness was approximately 10 years. ( B ) ElectromyographicJindings (Figs. 3 A and B ) The recording of muscle action potentials was made with disc metal electrodes placed on the surface of the muscle, 3 to 4 cm apart, and fed into an 8-channel inkwriting oscillograph through amplifiers with a time constant of 0.03 sec, and adequate high frequency characteristics. The EMG recording was routinely made simultaneously, from a pair of antagonistic muscles around a joint, as well as from the corresponding muscles of the contralateral side. The flexors and extensors of the upper arm (mm. biceps and triceps brachii), forearm (mm. flexor carpi radialis and extensor digitorum communis), thigh (mm. biceps femoris, semitendinosus and vastus lateralis) and leg

Fig. 3. Electromyographic findings before operation in Case 1. (A) Involuntary discharges and ). responses to muscle stretching, the duration of which is indicated b y a bar in each tracing ( Recordings were made simultaneously from both the agonist and antagonist of a joint, and include 4 pairs of tracings: the upper two from the right biceps and triceps brachii muscles (R.BB and R.TR); the lower two from the right biceps-semitendinosus and vastus lateralis muscles (R.BST and R.VF), and the right tibialis anterior and gastrocnemius muscles respectively (R.TA and R.GM). In thc upper recordings, the manipulations by the examiner inevitably lead to dystonic movements with a moderate amount of tonic discharges with rather regular grouping at the rate of 11 to 12/sec being observed, while stretching of these muscles produces no change or general decrease in the discharges. In the lower recording, the involuntary discharges are small in amount while an exaggerated stretch reflex is observed in the antigravity muscles (VF and GM). (B) Voluntary contractions. Upper pair from the right biceps and triceps brachii muscles (R.BB and R.TB), lower one from the right bicepssemitendinosus andjvastus lateralis muscles (R.BST and R.VF). Slightly delayed onset of maximal contraction of corresponding muscles develops following command of the examiner ( U I ~ ~ O W S111 ) . the recordings, the amount of discharges at the peak of contraction is abnormally small indicating muscle weakness. The tendency to grouping in the contracted niuscle, and abnormally excessive dischargcs in the antagonist, or disturbance of reciprocal inhibition, arc particularly well seen in the upper recording.

HALLERVORDEN-SPAT2

379

DISEASE

(mm. tibialis anterior and gastrocnemius) were examined in particular when the patient was relatively relaxed. The observations were restricted to the involuntary neuromuscular unit (NMU) CIS1 1 M.H.. 11D1R SISIM OF CASE 2 W H

3A CASE 1 M.H., ELDER SISTER OF CASE 2 K.H.

R.BB

1 R.TB

I

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1 SEC Fig. 3. For legend seelp. 378.

References p . 423-425

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N. Y A N A G I S A W A

et al.

discharges or action potentials from the muscle at rest, reaction to stretching of the muscle, and voluntary contraction. In voluntary contraction, attention was paid to the on- and off-pattern of NMU discharges and consistency of discharges during sustained contraction and, especially, the amount of discharges from the antagonistic muscle, i.e. the degree of reciprocal inhibition. The involuntary discharges at rest were summarized as follows. A small number of discharges were continuously observed in both of the antagonistic muscles. Corresponding to the dystonic movements, relatively tonic and sometimes continuing for more than 10 sec, high voltage discharges appeared diffusely in both of the antagonistic muscles. They tended to develop in group discharges of 11 t o 12 cycles/sec (Fig. 3A ; uppermost and second pairs of tracings). The above-mentioned characteristic representations of EMG were most intense in the upper extremities and rather dominant on the right side. The responses to stretching of muscles are summarized as follows : the stretch reflex was not identified in the upper extremities; during muscle stretch, occasionally no changes or diffuse reduction of discharges occurred (Fig. 3A; second pair). lntensive discharges were occasionally evoked nonreciprocally from both the stretched and antagonistic relaxed muscles and appeared as involuntary discharges resulting from positional changes. This type of discharge was evoked with a time lag after stretching, and was quite different from the stretch reflex observed in parkinsonian rigidity where an increase of discharge is restricted to the stretched muscle proportionally to the degree of displacement around the joint. Thus, in the upper extremities the resistance to passive displacement around a joint was responsible for the continuous and reflexlyenhanced involuntary discharges. In contrast to this, a slight ridigospastic type of stretch reflex was consistently observed in the knee extensor vastus lateralis and ankle extensor gastrocnemius muscles (Fig. 3A; 6th and 8th traces). This was easily detectable by virtue of the fact that in the lower extremities phasic burst discharges of nonreciprocal type were only rarely seen at rest or after stretching. The summary of voluntary contraction was as follows. Voluntary contraction was Fig. 4. (A) Coronal section through the marnmillary body (MB). Most-anterior portion of the ovalshaped oil-wax deposit is in the dorsolateral part of the left pallidum, while none is seen in the right pallidum. Pronounced rust-brownish discoloration in both pallidi. No lesions in the putamen (Pt), caudate nucleus (CN) or the anterior commissure (AC). (B) Coronal section slightly anterior to (A). Sharply-defined and diffuse demyelination in both pallidi, but no oil-wax. Symmetrical dilatation of the ventricles, x 1.2. (C) Left pallidum in (B). Dcposition of pseudocalcareous concretions particularly in the internal segment of the pallidum and focally in the anterior comniissure (AC). Pronounced pigmentary increase and cellular accumulation in all arcas of the pallidum, with spongy appearance in the dorsal part. TC = internal capsule. Putamen (crosses), x 5.3. @) Higher magnification of the pallidurn in (C). Coalescing pseudocalcareous concretions forming a concentric structure, x 440. (E) Coronal section through the subthalamic nucleus (STh). Single large, ovalshaped, operative lesion on the right (crosses) involving the internal capsule (IC) and the most lateral part of the thalamus (Th). Circumscribed demyelination around the former with narrow demyelinated streaks going from its ventral part to the cerebral peduncle (arrows). Two operative lesions on the left (crosses); one in the lateral part of the thalamus (Th); another in the dorsal portion of both putamen (Pt) and pallidum (GP). Slight to moderate demyelination in both pallidi. Synimetrically dilated ventricles, x 3.5.(B and E = Woelcke myelin; C Thionine; D = Hematoxylineosin.) ~7

MALL E R V 0 R D EN-S P A T 2 DISEASE

Fig. 4. For legend see p. 380. Refewaces p . 423-425

38 1

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relatively well accomplished in spite of such severe dystonia. The grouping of the discharges was also observed particularly in the upper extremities (Fig. 3B; upper pair of tracings). In some muscles, a disturbance of reciprocal innervation, i.e. appearance of high voltage activity in antagonism during voluntary contraction, was observed (Fig. 38; second tracing). The reduction of voluntary power was seen in all muscles tested as illustrated in Fig. 3B. Using the integrator of action potentials for measuring the amount of discharges, maximal contraction was found to be approximately one fourth or below that of normal subjects under the same conditions. In summary, nonreciprocal involuntary discharges with grouping around 1 1 cycles/ ses were predominant in the upper extremities, while slight stretch reflex of rigidospastic type was consistently encountered in the antigravity muscles of the lower limb. This probably explains the presence of clubfeet. ( C ) Neiiropathologir features Gross pathologic appearance of the central nervous system. The autopsy was restricted to the brain and spinal cord. The brain weighed 1120 g. In the parietal dura on both sides there were tiny spots representing the sites of needle introduction for stereotaxic surgery. The leptomeninges were thin and translucent. Both meningeal and base arteries appeared normal. The cerebral hemispheres showed slightly widened sulci in the frontal poles but were bilaterally symmetrical. The convolutions appeared normal except for two irregular scarred zones, measuring approximately 2 mm in diameter, in both parietal regions, resulting from stereotaxic surgery. In the coronal sections, both ventricles, especially the anterior horns, were symmetrically dilated. At the level of the mammillary body, an oval cyst measuring 5 x 7 mm occupied the external segment of the left pallidum and an adjacent circumscribed portion of the putamen, while two similar cysts were found in the left thalamus, and the internal capsule and the adjacent restricted areas of both thalamus and globus pallidus on the right side, respectively (Fig. 4E). The cysts were filled with a whitish-yellow substance and represented the stereotaxic oil-wax injections.

Fig. 5 . (A) Slightly caudal section to Fig. 4E. Narrow cellular band around the operative lesion (crosses). Pronounced discoloration and cellular mobilization in the pallidum (GP), particularly in its internal segment and, then, in the substantia nigra with well-preserved pigmented cells (SN). Cellular increase particularly in the ventroniedial part of the subthalamic nucleus (STh). Pt = Putamen, x 4.0. (B) Almost the same section as in (A). Intense, narrow gliosis a t the edge of the operative lesion (crosses), and similar but more diffuse gliosis in the internal capsule (IC)as in the medial part of the caudate nucleus (CN) due to the needle insertion (arrows). Slight to intense gliosis in the entire pallidum (GP), particularly in its internal segment and dorsal part, X 3.5. ( C ) Two sharply-demarcated, operative lesions (crosses) ; the left one involves the ventrolateral part and the reticular nucleus of the thalamus and, focally the adjacent internal capsule; the right one confined to the ventrolateral thalamus compressing the dorsomedial nucleus (DM). Narrow demyelinated band continuous from the thalaniic lesion into the white matter o n the left indicating the track of needle insertion (arrows). Similar dernyelinated streaks in the corpus callosum (CC), x 2.0. (D) Higher magnification of the needle track in ( C ) . Considerable mesenchymal network'proliferation surrounding the remaining yellowish-brown oil-wax (arrows),\ ~ ' 8 6 (A . - Thionine; B - Holzer C Woelcke myelin; D = Perdreau.)

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It is a noticeable finding that both pallidi, particularly their internal segments, showed a considerable increase of rust-brownish discoloration and minimal shrinkage (Fig. 4A). At the level of the lateral geniculate body, similar cyst formations were seen

Fig. 5. For legend see p. 382. References p . 423-425

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almost symmetrically in the ventrolateral parts of both thalamic nuclei (Fig. 5C). The left one measured 5 x 6 mrn and the track of the needle insertion from the scar at the lateral part of the superior frontal gyrus t o the cyst was traceable. The right lesion was larger in size and compressed the medial thalamic nuclei and the internal capsule. The rostra1 part of the substantia nigra, especially on the left side, showed a similar discoloration to that of the globus pallidus. It was much less intense, and appeared to be the normal color in its caudal portion. Cerebellum, brain stem and spinal cord appeared normal. Microscopic $findings. The lesions of the present example can, for convenience, be described in two categories: the surgical lesions and the changes relating to the essential disease process. However, as far as the present example is concerned, a clearcut differentiation between the two may sometimes not be easy, because no definite evidence as to the latter changes being independent of the neurosurgical intervention is available. This will be more definitely discussed later in regard t o the clinico-pathological features of Case 2 without surgical intervention. ( I ) Surgical lesions. Most of the oil-wax compound filling the cysts was lost during tissue fixation.The rest was composed oftinyhomogeneous granules whichwere intensely sudanophilic. The histopathological changes surrounding the operative lesions were, as a rule, confined to a zone measuring less than 1-3 mm in width (Fig. 5A). In the innermost zone a thin layer of the proliferated fibrocytes was present which was surrounded by mesenchymal fiber proliferation and a large number of multinuclear giant cells which contained needle-like structures (Figs. 6A, C and D). The latter appeared pinkish in a PAS preparation, but not sudanophilic. Outside this layer, an intensive gliosis had developed (Figs. 5B and 6B). It is of interest that perivascular cell cuffings, consisting mainly of plasma cells, were sporadically disseminated there, and clearly exceeded those of a symptomatic inflammatory response (Figs. 6A and E). Astrocytic nuclei became enlarged and pale, and tiny pigmentary granules were seen in their cytoplasmic processes. These were intensely iron-positive and moderately Sudan Black B-positive. The outermost zone of the lesions was characterized by nerve cell disintegration and disseminated phagocytes laden with PAS-positive, brownish pigmentary granules. The latter were also aggregated in the perivascular spaces. Perivenous lymphocytic infiltrations of a moderate degree were sporadically present and also exceeded those of symptomatic inflammation. These findings apply to the walls of both pallidal and thalamic lesions. In myelin preparations the walls appeared pale, measuring less than 1 mm i n width, and a narrow demyelinated band could be traced from the left thalamic lesion to the scar in the cortex (Figs. 4E and 5C). In the midbrain, narrow demyelinated streaks developed bilaterally in the medial part of the cerebral peduncle andcontinued into the ventral part of the operative lesions involving the internal capsule (Figs. 4E and IOB). I n addition to thc walls of the lesions, the adjacent internal capsule, the needle tracks in the cerebral white matter and the corpus callosum, and the adjacent cortices showed a moderate degree of circumscribed gliosis (Fig. 5B). Several small aggregations of phagocytes laden with intensely sudanophilic granules were noted in the

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Fig. 6. Edge of the operative lesion (crosses) in Figs. 5A and B. (A) Fibrocytic, multinuclear giant cell- and mesenchymal proliferations, gliosis and perivascular cell cuffs from the innermost to the outer layer, x 97. (B) Intense gliosis in the outermost layer of the lesion (crosses), x 96. (C) Thin layer of fibrocytic proliferation inside the operative lesion (crosses) and thick layer of mesenchymal network proliferation containing faintly-stained multinuclear giant cells on the outside, X 86. (D) Fibrocytic proliferation (crosses), multinuclear giant cells laden with needle-like structures, and perivascular cell cuffing, x 510. (E) Higher magnification of the area indicated by arrows in (A). A majority of the perivascular cell cuffs consist of plasma cells. Proliferated glio-mesenchymal fibers among the latter (crosses), x 1100. (A and D = Hematoxylin-eosin; B = Holzer; C = Perdreau.) References p . 423-425

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cavities corresponding to the needle tracks where thc remaining oil-wax surrounded by a considerable proliferation of mesenchymal networks was visible (Fig. 5D).

Fig. 7. For legend see next page.

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(2) Lesions relating to the essential disease process. The most noticeable findings in both globus pallidi consisted of a considerable accumulation of pigmentary granules, pseudocalcareous concretions and spheroid structures. Pigmentary granules were divided into three groups according to size and texture, namely tiny, globular and coarse concretions. The tiny pigmentary granules had accumulated in the cytoplasmic processes of astrocytes, most of which showed a progressive change with a large pale nucleus (Figs. 7A, B and C). They were also disseminated freely in the parenchyma and in the spheroid structures (Fig. 8A). They had a yellowish to light brownish natural color, stained green to deep blue with thionine and partly pinlush-red with PAS, and were iron-positive in various degrees (Fig. 7D). The pigmentary granules were distributed throughout the pallidum in an oro-caudal direction, and were most numerous in the internal segment (Fig. 5A). No particular difference was noted in their manner of deposition adjacent to the wall of the surgical lesion. The pigmentary globules were also disseminated throughout in the pallidum, and densely in its oral portion. They were mostly phagocytized in gitter cells, but also deposited freely in the parenchyma (Fig. 7E). They tended to accumulate in the perivascular spaces. They represented more brownish natural color and had similar but more intensive staining properties than fine granules. A smaller number of coarse concretions of a darkly-brownish natural color were disseminated freely in the parenchyma or accumulated periadventitially (Fig. 7F). These did not occur in relationship to any particular cellular elements. Pseudocalcareous concretions were mostly found symmetrically in the internal segment of both anterior pallida (Fig. 4C). Their whitish-brown precipitations could be seen in a celloidin section on naked eye examination, and reflected light more or less intensely. They were pseudomorphic in configuration, strongly refractile, and stained fairly uniformly compared to the above-mentioned pigmentary granules. With hematoxylin-eosin and thionine, the central core stained dark blue to black, while the marginal lamellae were pale (Fig. 4D). They were negative in the Von Kossa reaction for calcium, Thus the concretions were of a pseudocalcareous nature. The mode of deposition was, to some extent, similar to that of the coarse pigmentary granules: namely, they were freely in the parenchyma or in the periadventitial regions and inde-

Fig. 7. (A) A large number of yellowish-brown pigmentary granules and spheroids of an eosinophilic nature beneath the capsular wall of the operative lesion (crosses) indicated by arrows in Fig. SA, x 1 10. (B) Dorsal part of the pallidum in Fig. 5A. An exceedingly large number of granule cells and astrocytes laden with thioninophilic pigmentary granules, x 140. (C) Higher magnification of (B). A large number of tiny thioninophilic, pigmentary granules in the cytoplasmic processes of astrocytes with enlarged, vesicular nucleus (arrow), x 1000. (D)Iron-positive granules in astrocytic cytoplasmic processes. Lumina of the operative lesion (crosses) in the left pallidum in Fig. 4E, x 97. (E) Internal segment of the right pallidum. A large number of granule cells densely laden with PAS-positive granules. Also many tiny PAS-positive granules in astrocytic cytoplasmic processes. Two faintly-stained spheroids (arrows), x 460. (F) Same area as in (E). Coarse dark brownish periadventitial pigmentary concretions (arrows), x 470. (A and F = Hematoxylin-eosin; B and C = Thionine; D = Berlin blue; E = PAS.) References p. 423-425

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pendent of nerve cells or other cellular elements; and most of them were deposited in capillary walls or in the media of arterial vessels. Spheroid structures. A large number of fairly-homogeneous, round or ovoid struc-

Fig. 8. For legend see next page.

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tures was disseminated in the areas corresponding to those of the pigmentary accumulation. We use the term ‘spheroids’ according to the description of Cowen and Olmstead (1 963). The structures occasionally took a spindle-like or irregularly-round shape. In hematoxylin-eosin preparations they were light pinkish-red, well demarcated and disseminated freely in the parenchyma. They were less frequently blurred at the edge, and only visible because of their homogeneous eosinophilic texture (Figs. 7A and 8s). A fair number of them had no affinity to hematoxylin-eosin or thionine, but became more clearly visible in a slightly purple-pinkish color with PAS (Fig. 9A). Tiny pigmentary granules of various nature and staining properties were accumulated diffusely or focally in the spheroids (Figs. 8A and C). Argyrophilia was another characteristic property. However, the degree of silver impregnation varied, and they developed a series of colorations such as evenly light gray or deep black, or sometimes peripherally black with a pale central core in which exceedingly fine fibrillary networks could be seen (Figs. 8D, E and F). They were sporadically present in the stratum pedunculi intermedium (‘Kammsystem’) (Fig. 8G). However, a clear-cut relationship between the spheroids and the neuroaxons was only very rarely seen, and thus may resemble that of similar spheroids found in the gracile nucleus of experimental vitamin E deficient rats (Lampert et al., 1964) as well as in human materials from controls and various central nervous system diseases (Fujisawa, 1964). Miscellaneous changes in the globirspallidus. Diffuse, moderate demyelination (status dysmyelinisatus) was seen in the pallidi, and was predominant in their oral portions, where irregularly-shaped, comparatively well-defined pallor was observed and became more diffuse and less intense towards the caudal portion (Figs. 4B and E). Approximately the caudal half of the pallidum showed a slight lightening. The transverse gross fiber bundles were well preserved grossly, but microscopic examination revealed a diffuse disintegration of the fine fibers (Fig. 4E). The demyelinating process developed in the right pallidum which was free of surgical lesions, and thus may have no particular relationship to the operative procedures. Pyramidal cells were fairly well-preserved in the external segment (Fig. 9B), while certain neurons showed signs of central chromatolysis, shrinkage or pseudocalcareous deposition (Fig. 8B). Tiny granules, apparently similar to ‘lipofuscin’ in aged brains, accumulated in the cytoplasm of pyramidal cells. This was also seen in other neuronal cells throughout the brain and spinal cord (Figs. 9B and C). Corresponding to the demyelinated areas of the pallidum, a diffuse gliosis was observed which was Fig. 8. Internal segment of the right pallidum in Fig. 5A. (A) Similar to Fig. 7B. Spheroids laden with a smaller number of tiny thioninophilic, pigmentary granules (arrows), x 460. (B) Single, large, homogeneous1y-eosinophilic spheroid and pseudocalcareous impregnation, presumably of a shrunken nerve cell (arrows), x 550. ( C ) Large spheroid laden with different sized, abundant yellowish-brown granules, x 1000. (D) Large number of argyrophilic spheroids of different sizes and structures, x 110. (E) Higher magnification of two closely adjacent spheroids laden with argyrophilic granules indicated by arrows in (D), x 1100. (F) Single, large spheroid with intense argyrophilic zone marginally, and finely fibrillary network centrally, x 1200. (G) Higher magnification of the stratum pedunculi intermedium (‘Kammsystem’). Several spheroids with a fine fibrillary network (arrows), x 460. (A = Thionine; B and C = Hematoxylinxosin; D, E and G = Holmes’s simple silver; F = Hirano’s simple silver.) Rr,frrrrence.s p . 423-425

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Fig. 9. (A) Largc number of different sized spheroids, laden with PAS-positive granules. Similar granules in granule cells and astrocytic cytoplasmic processes, x 150. (B) External segment of the right pallidurn. Comparatively well-preserved pyramidal cclls laden with PAS-positive granulcs farrows) with fewer pigmentary granules and spheroids, X 150. (C) Large number of greenish-blue pigmentary granules in the cytoplasm of pyramidal cells, x 1000. (D) Area of the putarnen adjacent to the pallidurn (crosses). Coarse pigmentary concretions showing PAS-positive and yellowish-brown natural colors and a smaller number of spheroids perivascularly (arrows), X 153. (E) Putamen. Acute swelling of two pyramidal cells of the large type. Deposits of pigmentary granules in the cytoplasm indicated by arrow, x 950. (F) Substantia nigra at the level of the midbrain. Pronounced cellular increase in both compact and reticular zones. Well-preserved pigmented cells in the compact zone. Cerebral peduncle (crosses), x 89. (A, B and D PAS; C, E and F = Thionine.)

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particularly dense in the dorsomedial portion adjacent to the internal capsule (Fig. 5B). The astrocytic nuclei laden with pigmentary granules in their cytoplasm became enlarged, paler, and occasionally elongated. Phagocytic cells laden with tiny granules deep-pinkish with PAS also increased in number. There was no particular change in the vascular system. Putamen and caudate nucleus. Both nuclei were almost free from the characteristic histopathological syndrome seen in the globus pallidus. A few coarse pigmentary concretions of a darkly-brownish natural color with no particular relationship to certain cellular elements, as well as spheroid structures, were disseminated in a circumscribed area of the putamen closely adjacent to the pallidum (Fig. 9D). Both large and small types of nerve cells showing a tendency to acute swelling were well-preserved, while ‘lipofuscin-like’ granules were increased, particularly in the cytoplasm of the large type of nerve cells (Fig. 9E). Gross fiber bundles appeared normal in architecture, but oligodendroglial nuclei were shrunken and dark. Substantia nigra. The same changes as in the globus pallidus were seen in the reticular zone, but in much lesser degree. Tiny pigmentary granules of a yellowish-brown natural color were deposited freely in the parenchyma or the cytoplasmic processes of astrocytes. Only very few spheroids could be detected in any preparation of any stain. N o pseudocalcareous concretions were found, and a moderate astrocytosis and gliosis occurred in the reticular zone, while the compact zone appeared normal and the well-preserved pigmented cells showed no alteration (Figs. 5A and 9F). Subthalamic nucleus. In the ventromedial portion, a slight reduction in number of nerve cells and a concomitant increase of glial nuclei were noted (Figs. 5A and 10A). Nerve cells at the periphery of the nucleus were evenly shrunken and the perineuronal spaces were dilated. There were no spheroids or demyelination. Internal capsule. Spheroids in a minimal to moderate number were disseminated along the internal segment of the globus pallidus. A few narrow demyelinated streaks with an accumulation of phagocytes laden with PAS-positive granules and increased glial nuclei occurred bilaterally from the ventral portion of the operative lesions, partly involving the internal capsule, and reached the medial portion of the cerebral peduncle in the midbrain (Figs. 4E and 10B). Cerebral cortex. Cerebral gray and white matters were normal in architecture. Nerve and glial cells appeared normal, except for acute swelling, particularly of large pyramidal cells with some increase of ‘lipofuscin’ in their cytoplasm. No spheroids were encountered. Cerebellum, pons and medulla oblongata were normal, except for a generalized accumulation of ‘lipofuscin-like’ granules in the neuronal cytoplasm, and slight demyelination of the pyramidal tract. The narrow demyelinated streaks in the cerebral peduncles at the midbrain gradually lost their defined contour and faded intoa diffuse, slight pallor at the level of the pyramid from the pons to the medulla oblongata. This was best seen on the right side (Fig. IOC). In the gracile funiculi and nuclei, several spheroids were seen which were similar to those in the pallidum (Fig. IOE). Spinal cord. Minimal to moderate demyelination in both lateral and anterior References p . 423-425

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Fig. 10. (A) Ventromedial portion of the subthalamic nucleus in Fig. 5A. Nerve cell disintegration of a slight to moderate degree and considerable increase of glial nuclci, x 96. (B) Midbrain. Narrow demyelinated streaks bilaterally in the cerebral peduncles (arrows). R - right; L - left, x 1.6. (C) Midmedulla. Slight to moderate demyelination in both pyramidal tracts, predominantly on the right. R - right; L = left, x 3.5. (D) Cervical cord. Slight to moderate demyelination in the anterior and lateral colunins bilaterally, predominantly on the left. R right; L - left, X 7.0. (E) Gracile nucleus at the caudal end of the medulla oblongata. A fair number of homogeneously-eosinophilic spheroids can be seen (arrows with crosses). Adjacent shrunken nerve cells (arrows), x 490. (A Thioninc; B-D = Woelcke myelin; E = Hematoxylin-eosin.) L

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columns was observed at all levels, mostly involving the left lateral column (Fig. IOD). Corresponding to these lesions, astrocytosis, gliosis and tiny glial nodules were noted, but no particular changes were seen in the anterior horn cells. ( I l ) Case 2

( A ) Clinicalfeatures Past history. The patient K. H., the younger sister of Case I developed the same illness as her sister, and died on 8 April 1964 at 20 years of age. She had been delivered smoothly after a 9-month pregnancy. Her birth weight was 2030 g. She began to walk and speak at 14 years. In childhood she was physically healthy but feebleminded. Her school work was poor. She was restless, and occasionally wandered out of the class room. Consequently, at 10 years of age she had to be admitted to an asylum for mental defectives, but no physical disorder was noted at that time. The unskilful voluntary action of the right hand was the first physical sign which appeared at 12 years of age. During the subsequent several months an involuntary twist of the hand developed on action, and the left hand became involved in a similar manner. The torticollis to the right side manifested when walking. By the following year her gait had become unsteady, speech had become slurred, and she would fall easily. These symptoms and signs gradually progressed, and she was admitted to the Moro Mental Hospital, Moro, on 17 July 1960. Status 011 admission. The patient was a comparatively well-nourished young female. She demonstrated abnormal movements and postures whenever she intended to stand, walk or carry out any skilful actions using her fingers. In walking, the head turned toward the right-upper direction, the right arm extended backwards at the shoulder joint, and the forearm overpronated with moderate flexion at the wrist. The hip was protruded backwards as a result of a Iordosis of the lumbar spine (tortipelvis). The lower extremities were much less involved except for a slight inversion of the feet, and she could walk without difficulty. These abnormal contractions of the bodily musculature disappeared completely when the patient relaxed in a supine position. The pupils were round and equal, and responded normally to light and to convergence. Kayser-Fleischer corneal rings were not seen. No nystagmus was present and ocular movements were normal. Voluntary movements of the tongue, especially its protrusion, were restricted. She could eat with a spoon, but could not write ‘Kana-letters’, although she had been able to write them before her illness. The patient exhibited frequent attacks of involuntary twisting of the upper body half and torticollis to the right. The grimaces with the half-opened mouth and hypersalivation appeared continuously, and the lower lip was held tightly with the upper teeth. Passive displacement of the arms encountered moderate resistance and was followed occasionally by increased tension in both the flexor and extensor muscles around the joints. This was demonstrated by palpation and by electromyographic examinations. Both opisthotonos and clubfoot developed conspicuously while walking. In the supine position the lower extremities showed a tendency to slight scissoring, but no rigidity could be detected. Bolh patellar and Achilles tendon reflexes on both sides were exaggerated, while References p . 423-425

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Babinski's sign was present on the left side. Spontaneous speech was scanty and syllabic. She did not answer questions, and, as the dystonic movements increased, her behavior became more childish and hysterical. She could however recognize the doctors, and her orientation for place and person was preserved. It was impossible to have her undergo any psychological tests. In the succeeding years, the physical and mental disturbances progressed slowly, and the former showed recurrent spontaneous remissions of a slight degree. At the latest stage, the contractures of the masseter became so intense that the pressure of her teeth caused persistent, severe, non-healing ulcers on the left lower lip. She died of aspiration pneumonia on 8 April 1964. The total duration of the illness was over 8 years.

( B ) Electromyographic findings (Figs. 11A and B) This patient showed essentially the same pattern and distribution of abnormal E M G as in Case 1. In the upper extremities, involuntary phasic or tonic discharges of nonreciprocal type appeared in the upper arm (Fig. 1 1 A), and, to a lesser extent, in the forearm muscles although there was no tendency to grouping of action potentials. They sometimes developed synchronously in the corresponding muscles of the contralateral side. On both sides, muscle stretch evoked no significant changes in the basic involuntary discharges, i. e. no stretch reflex was detectable (Fig. 11B; upper two pairs of tracings). On voluntary contraction, flexion at the elbow could be accomplished smoothly, but extension was disturbed by simultaneous contraction of the antagonist, especially on the right side. In the latter, the action potentials from the extensor only gradually developed with contraction, and smooth attainment of maximal potentials could not be obtained. These findings coincided with the posture of flexion at the elbow and were frequently observed. The pattern of involuntary discharge in the forearms was the same as that seen in the upper arms, but occurred less frequently. The rigidospastic type of stretch reflex was present to a slight degree in the left flexor group. Voluntary contraction was relatively smooth except in the right extensors where maximal contraction was weak, and about the same amount of discharges appeared concomitantly in their antagonists. A slight tendency to grouping was observed'only in the left extensors of the forearm among all the upper extremity muscles examined. The muscles in the lower extremities were much less affected than those of the upper extremities. No stretch reflex nor phasic involuntary discharges were detected (Fig. 11B; lower two pairs of tracings). A slight impairment of voluntary contraction, i.e. inconsistency of sustained contraction of the right biceps-semitendinosus and concomitant contraction of the antagonists on the left knee flexion, was observed. ( C ) Neuropathological,features Gross pathological appearance of the central nervous system. The autopsy was restricted to the brain and spinal cord. The brain weighed 1150 g. The convolutional pattern of the cerebral hemispheres was normal. The leptomeninges were translucent except for a slight thickening of the pia along the underlying vessels. The cortical~vessels were slightly injected in both parieto-occipital areas, and a small hemorrhagic focus,

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400JN

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Fig. 11. Electromyographic findings in Case 2. (A) Involuntary discharges at rest of two pairs of muscles studied simultaneously; upper one from right biceps and triceps brachii muscles (R.BB and R.TB); lower one from left biceps and triceps brachii muscles (L.BB and L.TB). In the recordings, non-reciprocal burst discharges interrupted by silent periods are observed to correspond t o tonus fluctuation revealed by clinical inspection. Distinct grouping as seen in Case 1 (Fig. 3A) is not visible. (B) Involuntary discharges and responses to stretching of muscles, duration of which is indicated by a bar in each tracing (-). From top to bottom: right biceps and triceps brachii (R.BB and R.TB), left biceps and triceps brachii (L.BB and L.TB), right tibialis anterior and gastrocnemius (R.TA and R.GM), and left tibialis anterior and gastrocnemius muscles (L.TA and L.GM). In the recordings, the involuntary discharges are marked in the upper extremities, while no distinct stretch reflex can be seen in any of the muscles tested. References p . 423-425

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Fig. 12. (A) Coronal section through thc most caudal part of the niammillary body. Pronounced rust-brown discoloration in a crescent distribution of almost the entire area of the globus pallidus exccpt for the lamina medullaris and the ansa, with sparing of the putamen (Pt) and claustrum (CI). OT - optic tract; IC internal capsule. (B) Coronal section through the manimillary body (MB). Conspicuous increases in both pigments and cellular elcments in both globus pallidi, with sparing of the putamen (Pt) and caudate nucleus (CN). Pseudocalcareous deposits in the left pallidum, x 1.8. ( C ) Almost the same section as in (B). Deniyelination predominating in all areas of the left pallidurn, but restricted to the dorsal part of the right pallidurn. N o abnormalities in caudate nucleus (CN) and putamen (Pt). MB mammillary body; A C - anterior commissure; Am amygdaloid nucleus, x 2.3. (B Thionine; C = Woelckeniyelin.)

-

7

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:

approximately the size of the tip of the small finger was present subpially in the left parieto-occipital area. The basilar arteries and inferior surface of the brain appeared normal. In coronal sections, an exceedingly intense rust-brownish discoloration ap-

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peared bilaterally in the globus pallidus, particularly predominant in their dorsomedial and internal portions (Fig. 12A). No change in their size was noted. At the level of the mammillary body, the reticular zone of the substantia nigra continuing from the internal pallidum showed a similar discoloration bilaterally but more predominant on the left side. Both lateral and third ventricles showed a slight degree of symmetrical dilatation. The cerebral cortex and white matter, diencephalon and hypothalamus appeared normal. In the midbrain minimal atrophy of both cerebral peduncles was noted. The compact zone of the substantia nigra showed a minimal depigmentation bilaterally, slightly more so on the left. The color of the reticular zone at this level was almost normal. Brain stem, cerebellum and spinal cord appeared normal. Microscopicfindings. As far as the conspicuous findings of the globus pallidus were concerned, they were essentially the same as those in Case 1 : a large number of spheroid structures, enormous deposits of both pigmentary granules and pseudocalcareous concretions, demyelination and gliosis. Both demyelination and gliosis varying in degree from slight to severe occurred bilaterally and diffusely in the anterior portion of the globus pallidi, and extended dorsomedially along the internal capsule caudally (Figs. 12C and 13A). Tiny pigmentary granules in the cytoplasmic processes of astrocytes and globules in gitter cells increased conspicuously (Figs. 12B, 13D and E, 14A and B). Both the number and the staining properties of the spheroids, as we11 as the nature of the granules within them were essentially similar to those of Case 1, although their basophilia was less intense (Figs. 13D and E, 14A and C-F). The laterality, localization, nature and number of pseudocalcareous concretions were also similar (Figs. 12B, 13B and C ) . The finding that pyramidal cells, particularly in the external segment, were comparatively well preserved was identical to that of Case 1 (Figs. 13D and C). Both putamen and caudate nucleus were free of changes, except for a circumscribed portion of the putamen closely adjacent to the pallidum which showed the same changes as those in the latter nucleus. Lipopigments were increased in the nerve cells of the large type. The substantia nigra exhibited both astrocytosis and gliosis in a 4ight to moderate degree (Figs. I3A, 15A and B), while pigmentary deposition in the reticular zone was less pronounced as compared with that in the pallidurn. Very few spheroids were encountered (Fig. 15B). The pyramidal cells were well-preserved in both reticular and compact zones, but a few pigmented cells were disintegrated. Disintegration of nerve cells and the corresponding proliferation of glial nuclei were observed in the ventromedial portion of the subthalamic nucleus, and were of the same pattern as in Case 1 (Fig. I5C). The remaining nerve cells had moderately shrunken pyknoticnuclei. The cerebral cortex was intact, except for an increased deposition of pigmentary granules in the cytoplasm of neuronal cells, particularly of the large pyramidal type. There were no changes in the thalamic nuclei. The spinal cord was almost intact, except for a minimal bilateral demyelination of the lateral columns and toca1:disintegration of both anterior and lateral horn cells in very mild degree, associated with retrograde degeneration of a few cells at all levels (Figs. 17A, B and C). The following two findings, which had been inconspicuous in Case 1, were rather unusual. (a)"Tn several cerebellar folia, both Purkinje and 'granule cells were more or Refeueni cs p 423-425

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al.

Fig. 13. For legend see next page.

HA L L E R V 0 R D EN .- S P A T Z D I S EASE

399

less disintegrated and glial nuclei proliferated in both Purkinje and molecular layers (Fig. 15D). Several glial shrubberies, with or without neuronophagia of Purkinje cells were scattered (Figs. 15E and F). Typical ischemic changes occurred not infrequently in the Purkinje cells. These two changes might suggest a relatively recent lesion. Moderate astrocytosis developed around and/or within the dentate nuclei with relatively good preservation of the nerve cells. (b), The nerve cells of both gracile nuclei were severely disintegrated (Fig. 16A), while an exceedingly large number of spheroids of different sizes and structures were clearly seen in silver preparations (Figs. 16B and C). The pathomorphology of those spheroids was essentially similar to those seen in the globus pallidus, but differed from them in that they contained no pigmentary granules. It is of interest that these spheroids were never observed in the adjacent cuneate nuclei. A Best’s carmine preparation with low power magnification clearly indicated the entire area of the gracile nuclei (Fig. 16D), while higher magnification demonstrated deposition of a large number of tiny carmine-positive granules in the cytoplasmic processes of astrocytes, rarely in their nuclei, in the cytoplasm of the remaining nerve cells, but also in large quantities in the parenchyma, particularly around the spheroids described above (Fig. 16E). Similar carmine-positive granules were widespread from the basal ganglia to the cerebral cortex. These occurred freely in the parenchyma, in lesser numbers in the cytoplasmic processes and nuclei of astrocytes, and rarely in the cytoplasm of nerve cells and periadventitial spaces (Figs. 18E and F). These carmine-positive granules found in the globus pallidus will be referred to below. (III) Histochemicaljndings in Cases I and 2

The histochemical studies encompassed both spheroids and pigmentary granules of the globus pallidus and substantia nigra, as well as the intraneuronal pigmentary granules of both cerebral and cerebellar cortex. The data obtained are summarized in Table I. Spheroids. Two essential components of the spheroids were detected with routine stainings, i.e. a homogeneous structure filled up the spheroid body, while fine to coarse pigmentary granules accumulated peripherally or unipolarly. These granules were observed only in a certain number of spheroids and’seemed closely to resemble the abundant pigmentary granules present in astrocytic cytoplasmic processes, such granules Fig. 13. (A) Almost the same section as in Figs. 128 and C. Moderate to intense gliosis restricted to both globus pallidi, corresponding to the lesions in Figs. 12B and C. No gliosis in putamen (Pt) or caudate nucleus (CN). Moderate gliosis in the substantia nigra (SN) on the right, x 1.9. (B) Globus pallidus in Fig. 12B. Various-sized deeply thioninophilic pseudocalcareous concretions mainly in the vessel walls. Pronounced cellular increase in the parenchyma, x 89. (C) Higher magnification of (B). Pseudocalcareous deposits in capillary walls. Well-preserved pyramidal cells (arrows), X 480. (D) Considerable increase of pigmentary granules in the cytoplasmic processes of astrocytes and gitter cells, with a few spheroids laden with thioninophilic granules (arrows). Comparatively well-preserved pyramidal cells, x 110. (E) Higher magnification of the right upper corner in (D). Considerably enlarged astrocytic nucleus (arrows) and one spheroid laden with tiny thioninophilic granules (arrows with dots), x 513. (A = Holzer; B-E = Thionine.) References p.-423-425

400

N. Y A N A G I S A W A

et al. TABLE

HISTOCHEMICAL P RO P E RT I E S O F S P H E R O I D S A N D P I G M E N T A R Y G R A N U L E S I N THE G L O B U S P A L L I D U S , S P A T Z D IS EA S E A N D O F C O N T R O L W I T H

(-

=

All methods are according to Pearse No information; 0 = Negative; i = Minimal; Present two examples of

Case number

Globus

Staining

Spheroids Homogeneous structures

Pigmentary granules

-

PAS After saliva for 30' After acetylation After pyridine for 24 h, 18"

1*

2** 1 2 1 2 1

&-1 I

I + -2-b 1+ - 2 + *-I+ I f 0

* &-I+ zt

0 0

0 1 I-

0 - If

2 1 2 1 2

f

0

0 - ((1 +)I

Alcian blue

1

0 0

Congo red

2 I 2

Metachromasia

1

Toluidine blue

2 I

0 0 0 0 0 0 0 0 0 - rt

After chloroform-methanol for 24 h, 60" Best carmine

I t 11 -21 l i

-I

*0

0

0

2

0 0 0 -

Acetic acid-cresyl violet

1

0 0

Sudan 111

2 1 2 1 2 1

0 0 0 0

2 1 2 1 2 1 2

0

0- f 0- f 0 0 0

0 - 1+ 0 - 1+ 0 0 0 0 0

1 2 1

0 0 0

0 0 0

2

0

1

0

2

0

0 0 0

Sudan Black B After chloroform-methanol for 48 h, 60" Copper phthalocyanin Phosphomolybdic acid** * PFAS Bial (Diezel, 1957) Gallocyanin-chromalum (pH 1.9) Feulgen

-

* Case 1, elder sister, M. H. ** Case 2, younger sister, K. H. *** From frozen sections

0- I + 0 - 1+

(( )) very rare irlcid~-z.

HALLERVORDEN-SPATZ

401

DISEASE

I SUBSTANTIA N I G R A A N D CORTICAL N E U R O N A L CELLS OF TWO EXAMPLES OF HALLERVORDENP A R K I N S O N I S M A T 13 Y E A R S O F A G E

(1960) except for Bial reaction. 1 1 - Slight; 2 i = Moderate; 3 +

-

High)

Hallervorden-Spatz disease

Control with parkinsonism ~

palliclus ~~~

Pigmentary granules in astrocytes 0- f 0-1 I + - I Ii - 1 I

0 0 0 - 1+ 0- I+ 0 - 1+ 0 - 1+ 0 0- l i 0 0 0 0 0 0 0 0 0 0

Pigmentary granules in phagocytic cells

Pigmentary granules in nerve cells of whole brain

+-3+ 1-3+

1+ - 2 +

~~~~

f-2+ f-21 0- 1 0 +-31

t-31 +-3 I 0-3+ 0-Zt

0- I+ 0 0 0- 5 0 0 0 0 0 0 0 -

t -11 1-21 -I - I f 0-2 I

+-21 0 0 -

0 0 0 0 0 0 0 0 0

+ -2+ I+ -2+ I + -2t *-2i 2i

0- I 0

-

+ +

0000 0 0 0 0 0

*

Referenced p. 423-425

2+ 1+ - 2 + I + -2+ 0

0 f-2+ I + -211+ I+- - 2 t 0-lt 0 0 0-+ 0 0 0 0 0 0 0 0

Melanin pignients in substantia nigra in Case I

Reddish yellow brown Reddish brown

0 Reddish yellow brown Reddish brown

~

Physiological Pigmentary granules in globus pallidus

Pigmentary granules in nerve cells of whole brain

0- 1+

1+ - 2 +

0- I +

li- -2+

0

0

0-1+

1-1- - 2 t

0 - 1+

1+ - 2 +

0

0-1+

0- &

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

1+ - 2 + 1+-2i-

0

-

I+ -2+ I + -2+ I + -2+ 2+ 00- &

1 -t

0-1-t

I+ -2t

1+

0-1+

2+

0

0 - tr

*

*

-

0 0 0- t 0 0

i

0

0

0

0

0

0- f

0

0

0

0

0

0

0

0

0

Zt

0 0

402

N. Y A N A G ~ S A W Aet

al. TABLE I

H I S T O C H E M I C A L P R O P E R T I E S OF S P H E R O I D S A N D P I G M E N T A R Y G R A N U L E S I N T H E C L O B U S P A L L I D U S , S P A T Z DISEASE A N D O F CONTROL WITH

(-

=

All methods are according to Pearse N o information; 0 = Negative; $ = Minimal;

~-

Present two examples of Staining

Case number

Glohus Spheroids Homogeneous structures

Hg-bromphenol blue Coupled tetrazonium Millon

Dimethylaminobenzaldehyde-nitrite Naphthyl ethylenediamine Alkaline tetrazolium Ferric ferricyanide Sakaguchi for Thomas's modification Long Ziehl-Neelsen Schmorl Masson-Fontana Ferrous iron uptake HzOz bleaching (lo%, 24 h)

Chromalum hematoxylin Berlin blue Copper (rubeanic acid) Calcium (Von Kossa)

1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2

I 2 1 2 1 2 1 2 1 L

Methylene blue extinction (pH)

1 2

1+-3+ 1+-2+ 1 -I- - 3 I+ -3+ 1+ 1+-2+ 4- 2 + 1+ 0 0 0 0

+

zt

*-I+ +-I+ *-I+ *-I+ 0-

+

f

0

Pigmentary granules

I i1+ 2+ I+ -2+ *-I+ 1+ 0 0 0

0 0 0

1-1I+ -2+ & I+ -2+ 1+ - 2 + I+

I iI+

f

1 -k + - I tk-l+

0

0

0

i

-

0 0- I+ -

0 0 0 3.88 -

2+ 2+

0 0-1+ 0 0 0 3.20

-

403

HALLERVORDEN-SPATZ DISEASE (continued) S U B S T A N T I A N I G R A A N D C O R T I C A L N E U R O N A L CELLS O F T W O E X A M P L E S O F H A L L E R V O R D E N -

73 Y E A R S O F (1960) except for B i d reaction. 1-1- - Slight; 2 1 = Moderate; 3 I

PARKINSONISM AT

-

~

AGE

-

High)

~.

~~~~

Hallervorrlen-Spatz disease ,

~

Control with parkinsonism

~

pallidus ~

~

-

Pigmentary granules in astrocytes

Pigmentury granules in nerve cells of whole brain

Melanin pigments in substantia nigra in Case 1

Physiological pigmentary granules in globus pallidus

Pigmentary granules in nerve cells of whole brain

1-21

0 - i

0

f

i

I I

t

-

Pigmentary granules in phagocytic cells

~-

I+

i k

.L

-11 1 -1-

I i t -1 t 11 0 0 0 0 0 0 0- I 1 1 1 0- 1 0- 1

I i -21 I I -2+ 0- I t 1-

0- l i 2A + - I 1-

1-1 1 0-2t 1 t--21 i -11

I+

1 1 -21 lt-21

li 1+ 0 0 0

+

1+ - 2 +

0

0 - i-

1 -t

k

0 0 0 0 0 0

0

-

0

0

0

0

I

t

3+

1 1 -21 0 - -I

1+

0

0 0

+-I

0- t 2t-3+ 2+ - 3 + 0- l i I+ 0-21 2t -31 + - I 1 1-1 I 21 - 3 1 2t-31 +-I+ 0-3+ 0 21-

0 0 0

0 0

i f

0

2+ L - 2 k

rt

+

I+ 0

+

I+ -2+ 2+ 0 0 0

-

-

-

+

0-

2 -t

3 i-

00 0- I+

.-li

1 - 1 1 0-31 0-2f

Below 2.62

2+ - 3 +

1+ +-1+

3+

2+

I 1+-3+

+ 0

*-I+

3+

0-I+

3 f

1

0

+

2+

0

0-3+

0

0

0- I+

0

0 0

-

-

-

-

-

Below 2.62 -

3.20 -

3.20

3.20

3.20

0

-

Refirefires p .

~

423-425

404

N. Y A N A G I S A W A t?f 01.

Fig, 14. Globus pallidus. (A) Tiny thioninophilic, pigmentary granulcs in the niargiiial a r m of the spheroid, with similar granules in the cytoplasmic processcs of astrocytcs (arrow), x 1050. (B) Swollen cytoplasm of gitter cells with dark shrunken, eccentric nuclei and laden with coniparatively coarse yellowish-brown granules, x 660. ( C ) A fair number of various-sired spheroids with different structures, x 160. (D) Oval-shaped, large spheroid laden with an exceedingly large number of tiny slightly heniatoxiphilic granules (arrows). Cytoplasm of adjacent pyramidal cell laden with yellowishbrown pigmentary granules (arrows with dots), x 1010. (E) Round spheroid laden with a large number of tiny intensely eosinophilic granules, x 1010. (F) Two spheroids demonstrating a fine fibrillary network and deeply argyrophilic tiny granules, x 1400. (A = Thionine; B -E ~- HemaHirano's simple silver.) toxylin-eosin; F

HALLERVORDEN-SPATZ

DISEASE

405

having essentially similar histochemical characteristics to those of the spheroids. The histochemical findings:. described, here concern only the homogeneous structure of spheroids which seem -to represent the essential endproduct of a dystrophic process of the neuroaxons. All spheroids, irrespective of size, were minimally to slightly positive to the PAS stain. This reaction could be blocked by acetylation, was unaffected by pretreatment with saliva or hot methanol-chloroform, and thus suggested the presence of 1,2 glycol grouping, i.e. a carbohydrate moiety, since they gave a negative performic acid-Schiff reaction (Figs. 9A and 18s). Acid-mucopolysaccharides were absent as witnessed by the lack of metachromasia with toluidine blue or acetic acid-cresyl violet, and a negative alcian blue stain. N o neutral fat or complex lipids were found in the spheroids, except for a very thin marginal layer with a Sudan Black B-positive reaction suggesting that a myelin sheath surrounds the spheroids which are essentially of dystrophic neuroaxonal origin. The Bial method for neuraminic acid, a component of gangliosides, failed to develop any distinct coloration. No positive reaction was obtained with gallocyanin chromalum (pH 1.9) or Feulgen stain for nucleic acids. Stains for aromatic amino acids (coupled tetrazonium, Millon, dimethylaminobenzaldehyde-nitrite etc.) were slightly to intensely positive (Figs. 19B and C). A dark to reddish-brown color developed in the coupled tetrazonium reaction which could be blocked by benzoylation. Mercury-bromphenol blue stain for protein was also positive and resulted in a deep blue to violet color (Fig. 19A). All these data along with methylene blue extinction at pH 3.88 indicate the presence of acidic proteinaceous components containing certain aromatic amino acids. The spheroids could reduce both alkaline silver solution (Masson-Fontana) and ferricyanide (Schmorl and ferric ferricyanide), but only to a minimal degree, and thus clearly contrasted with the intense reactions of the pigmentary granules to be mentioned later. The same was true for acid fastness (Fig. 19D) and ferrous iron uptake (Fig. 19F). Certain spheroids were iron-positive (Fig. 19H), while others were negative (Fig. 19G). In summary, the basic constituents of the homogeneous structure of the spheroids consisted mainly of proteinaceous substances combined with a small amount of carbohydrates, and resembled to some extent the biochemical peculiarities of the globus pallidus, particularly in regard to iron metabolism. Pigmentary granules. Tiny pigmentary granules in astrocytic cytoplasmic processes, pigmentary globules in phagocytic cells and dark-brownish, coarse pigmentary concretions randomly scattered showed essentially similar histochemical reactions though the intensity of reaction in each structure showed considerable variation. They were variably positive to the PAS stain, from faintly brownish-purple to dark red color, mostly dark red (Figs. 7E, 9A and B, 18C). Acetylation blocked the PAS reaction, but both hot methanol-chloroform and pretreatment with saliva resulted in no significant alterations. The granules failed to stain with alcian blue, and showed no metachromasia with toluidine blue or acetic acid-cresyl violet. In the globus pailidus of Case 2, glycogen granules were widespread in the cytoplasmic processes of astrocytes, rarely in their nuclei, as well as freely scattered in the parenchyma (Fig. l8D). With Sudan I11 stain, an orange color developed faintly to moderately, particularly Rrf'rrvces p . 423-425

Fig. 15. (A) Moderate, bilaterally symmetrical gliosis in the reticular lone of the substantia nigra, 7 3.5. (B) Lower magnification of the substantia nigra in (A). Pronounced cellular increase in the reticular zone, with well-preserved pigmented cells. Only one spheroid can be seen (arrow), )i 89. ( C ) Ventromedial portion of the subthalamic nuclcus. Moderate to high degree of nerve cell dis-

(continued next page)

Fig. 16. Gracile nucleus. (A) Severely disintegrated nerve cells, x 89. (B) Very large number of spheroids of different sizes and structures, x 490. ( C )Higher magnification of the spheroids. Finely or coarsely-fibrillary networks, faintly argyrophilic, tiny granules and central vacuole (arrow), x 1100. (D) Intensely carmine-positive gracile nuclei bilaterally (GN). Abundant accumulation of amyloid bodies marginally. Floor of 4th ventricle (crosses), x 17.0. (E) Higher magnification of (D). Tiny, carmine-positive granules in the cytoplasmic processes of astrocytes a? well as in the marginal areas around spheroids, x 1000. ( A = Thioninc; B and C - Hirano’s simple silver; D and E = Best carmine.) integration and proliferation of astrocytic nuclei, x 86. (D) Cerebellum. Disintegration of both granular and Purkinje cell layers, with cellular increases in both molecular- and Purkinje cell layers, x 33. (E) Typical glial shrubberies in the cerebellar molecular layer, shrunken Purkinje cells, and slight proliferation of Bergmann’s glial nuclei in the Purkinje cell layer, x 150. (F) Higher magnification of neuronophagia of a Purkinje cell, x 1000. (A = Holzer; B-F = Thionine.)

408

N . Y A N A G I S A W A rt

al.

Fig. 17. Lower thoracic cord. (A) Poorly defined, minimal dernyelination, bilaterally symmetrical in the lateral columns (arrows), A 8.5. (B) Minimal disintegration of nerve cclls in thc anterior horn in (A), Y 89. (C) Higher magnification of the pyramidal cell indicated by arrows in (B). Homogcncous, swollen cyloplasm and remaining marginal Nissl substance sugge7t retrograde degeneration of the Woelcke niyelin; B and C - Heniatoxylin eosin.) pyiamidal cell, F 1000. (A ~

inore intensely in the granules of the phagocytic cells, but a brilliant red color was never obtained. The Sudan Black B reaction was moderately to intensely positive in paraffin sections. The granules developed various intensities of a gray to black color, again most pronounced in the granules of phagocytic cells (Fig. 18G). They were

HALLERVORDEN-SPATZ

DISEASE

409

resistant to lipid extraction with hot methanol-chloroform, which suggested a firm combination with other biochemical components. Both the luxol fast blue and Bial reactions were negative. The coupled tetrazonium reaction developed a dark brown color, while with the Millon technic a faint color appeared superimposed on the yellowish-brown natural color (Fig. 19B). Nucleic acids were never demonstrated. The granules were somewhat argyrophilic in Holmes’s, Bodian’s, Glees’s and simple silver preparation (Hirano and Zimmerman, 1962), and reduced both alkaline silver solution and ferricyanide with various degrees of intensity. In the Masson-Fontana, the granules of phagocytic cells developed a dark gray to black color, which was less intense in the tiny ones in the astrocytic cytoplasmic processes (Fig. 19E). The granules were all acid-fast to a variable degree of intensity. In the long Ziehl-Neelsen they developed a pink to dark red color, most intense in the granules of phagocytic cells (Fig. 19D). In the substantia nigra, they demonstrated a clear-cut contrast to melanin pigments which were not acid-fast. Bleaching of the pallidal pigments revealed a difference from melanin pigments; after treatment with 10% HzOz for 24 h, the melanin pigments became almost completely decolorized and showed only a faintly yellowish shade, whereas the color of the pallidal pigmentary granules, although reduced slightly to moderately, remained brownish-yellow as before the bleaching. Ferrous iron uptake was specific and intense for the melanin pigments, but very scanty for the pallidal pigments. The pigmentary granules in both astrocytes and phagocytic cells were, in part, ironpositive (Figs. 7D and 19G), while the coarse pigmentary concretions without a relationship to cellular elements were all iron-positive without exception. These findings may be attributed to the peculiarity of iron metabolism of the globus pallidus and substantia nigra. In summary, the above-mentioned pigmentary granules may reasonably be said to belong to the category of so-called ‘Abnutzungs-Pigment’ combined firmly with certain carbohydrates, lipids and proteins. They are characterized by certain biochemical peculiarities, particularly of iron metabolism, though they represented the various stages of their maturity of which a part may be believed to occur through an autoxidizing process (Pearse, 1960). The histochemical properties of the pigmentary granules accumulated in the spheroids were essentially the same as those of the astrocytic cytoplasmic processes (Figs. 18A, B and H, I9A-H), and are summarized in Table T. An exceptional finding was that a very few spheroids in the globus pallidus of Case 2 seemed to contain glycogen granules (Fig. 18D). Pigmentary granules in nerve cells. With PAS preparations the granules were pale to brilliant pinkish, resistant to lipid extraction and exposure to saliva, and blocked almost completely by acetylation. A pale or brilliant orange color with Sudan I11 stain developed evenly in large nerve cells, especially in olivary and dentate nuclei, suggesting the presence of neutral fat in amounts felt to be abnormal considering the ages of the patients. The Sudan Black B stain was moderately positive in paraffin sections in which lipid extraction resulted in no significant alterations. They were negative to luxol fast blue, Bial and performic acid-Schiff stains. Stains for proteins, References p 423-425

410

N. Y A N A G I S A W A

c’t d.

Fig. 18. For legend see next page.

H A LLER VORDEN-SP A TZ DISEASE

41 I

aromatic amino acids and acid-fastness were moderately positive. All these findings were similar to those of the pallidal pigmentary granules, but differed from them in the following reactions : the intraneuronal granules were negative to Masson-Fontana, while the pallidal pigments were moderately to intensely positive; the former reduced ferricyanide iron in a minimal degree (Schmorl), while they developed a positive blue-black color in the chromalum hematoxylin method for lipofuscins. So far, the intraneuronal pigmentary granules belonged to the category of lipofuscin. The faintly yellowish natural color, their neutral fat content, and minimal positive Schmorl reaction indicate that they represent an immature stage in the course of the process of maturation of intraneuronal lipopigmentary metabolism (Pearse, 1960). DISCUSSION

The clinico-pathological festures of the present two cases justify the diagnosis of Hallervorden-Spatz disease. Certain atypical and unusual findings were present. Clinical aspects. The age of onset of the disease may vary considerably as has been shown by Gross et al. (1957). In many cases, mental deficiency or retarded physical and mental development were noted before the appearance of both neurological and psychic disturbances with their comparatively rapid progress and severity. Among sporadic cases, the earliest onset was in case 21 of the Vogts (1920) in which ‘Spannung’ of neck and extremity muscles developed a few months after birth while the latest was case K. S . of Eicke (1940) which started with stuttering speech at 38 years of age. In all others, onset ranged between the two, particularly around 10 years of age. Among familial cases, there was less variation; the earliest was 2- or 3-year-old (case 1 of Urechia eta/., 1950) while the oldest was the present Case I at 12 years. There is a general tendency for age of onset, duration of illness and clinico-pathological features to be strikingly similar in affected siblings. The conspicuous similarities in the symptomatology of 5 siblings in one family were first described in detail by Hallervorden and Spatz (1922). The neurological picture consisted of progressive stiffness starting in the lower extremities and subsequently involving the entire body musculature, associated with progressive mental deterioration.

Fig. 18. (A) Globus pallidus (Case 1). Large spheroid densely laden at one pole, with a large number of intensely PAS-positive, tiny granules, x 1000. (B) Globus pallidus (Case 2). Large homogeneously PAS-positive spheroid densely laden at its margin with a large number of tiny PAS-positive granules, x 1100. (C) Globus pallidus (Case 2). Cytoplasm of gitter cells laden with PAS-positive granules, x 520. (D) Globus pallidus (Case 2). Tiny carmine-positive granules in the astrocytic cytoplasmic processes, in the spheroid bodies (arrows) and lying free in the parenchyma, x 950. (E) Putamen (Case 2). Single, tiny, carmine-positive granule in the astrocytic nucleus (arrow), with similar large one closely adjacent to nucleus (arrow with dot), and additional small ones in the parenchyma, x 1550. (F) Putamen (Case 2). Moderate number of tiny carmine-positive granules in the periadventitial space, x 1100. (G) Globus pallidus (Case 2). Sudan Black B-positive granules in the gitter cells and the cytoplasm of the pyramidal cells, x 100. (H) Globus pallidus (Case 1). One spheroid with Sudan Black B-negative granules on the left, with another laden unipolarly with Sudan Black B-positive granules on the right (arrows), x 513. (A-C =PAS; D-F =Best carmine; Gand H = SudanBlackB.) References p . 423-425

412

N. Y A N A G I S A W A

et ul.

Fig. 19. For legend see next page.

HALLERVORDEN-SPATZ

DISEASE

413

The two siblings of the present report showed identical clinical courses. The onset of the disturbance of skilful movements with unilateral athetoid motion of the upper extremities appeared at 13 and 12 years of age, respectively. Subsequently, spasmodic torticollis and severe dystonic movements o f both upper extremities developed. The lower extremities also became stiff but less severely, and as a matter of fact, the younger patient, K. H., could still walk without support in the final stage of the disease. Electromyographic analysis showed that, corresponding to the dystonic movements, the sustained involuntary activity developed simultaneously in both agonists and antagonists, and was interspersed by random silent periods. Such patterns are commonly seen in torsion dystonia and are similar to the results of E M G analysis of dystonia reported by Hoefer and Putnam (1940), and Herz (1944a,b). In that course the grouping discharges at the rate of 1 I to I2/sec were observed in Case 1. It should be noted that the resistance to passive displacement of the upper extremities was not due to increased stretch reflexes as seen in parkinsonian rigidity (Denny-Brown, 1962; Shimazu et al., 1962), but to sustained tonic contraction of both the agonist and antagonist muscles. On the contrary, the stiffness of the lower extremities and clubfoot deformity present in Case 1 could be attributed to increased stretch reflexes of the rigidospastic type. In summary, from both clinical inspection and electromyographic analysis the present two siblings were affected by severe dystonia of the upper extremities as well as minimal to moderate rigidity of the lower extremities. Involuntary hyperkinesis including torsion dystonia or spasm has sometimes been a clinical manifestation in previouslyreported Hallervorden-Spatz disease (Hallervorden, 1930; Osman and Schiikrii, 1935; Benda, 1949; Netzky et al., 1951). The case of Fischer (191 I), which was published before the establishment of the concept of dystonia as a clinical entity, exhibited motor disturbances which could reasonably be interpreted as torsion dystonia judging from his detailed description. Case J of Korney (1964) could also be referred to as dystonia. Involuntary movements of the extremities and facial muscles, i.e. athetosis, choreo-athetosis, or facial grimacing, have been observed in many caSes (case 21 of the Vogts, 1920; Onari, 1925; case Friedrich of Kalinowsky, 1927; Hallervorden, 1930; Vincent and Van Bogaert, 1936; Meyer and Earl, 1936; Wahlstrom, 1946; Scharenberg and De Jong, 1952; case 2 of Zeman and Scarpelli, 1958). Three cases of Kalinowsky (1927) and case 1 of Funfgeld (1930)

Fig. 19. Globus pallidus in Case 1. (A) Spheroid densely laden with a large number of tiny Hgbromphenol blue-positive granules, with a fine fibrillary network, x 1100. (B) Various sized coupled tetrazonium-positive spheroids, x 513. (C) Spheroid with a large number of dimethylamino-benzaldehyde-nitrite-positive tiny granules and fine-fibrillary network, x 1200.(D) Ziehl-Neelsen-positive granules in the spheroids, the gitter cells and the astrocyticcytoplasmic processes, x 470. (E) Spheroid laden with a large number of tiny Masson-Fontana-positive granules peripherally. Similar granules in adjacent gitter cell (arrow) and astrocytic cytoplasmic Erccesses, x 1000. (F) Large spheroid laden with granules positive in ferrous iron technic (arrows). The two adjacent spheroids are negative or only minimally positive, x 1000. ( G ) Iron-positive granules in the cytoplasmic Drocesses of astrocytes, with the iron-negative spheroid (arrows), x 1000. (H) Putamen. Two different sized ironHg-bromphenol blue; B = Coupled tetrazonium; C = Dimethylpositive spheroids, X 1000. (A amino benzaldehyde-nitrite; D = Long Ziehl-Neelsen; E = Masson-Fontana; F = Ferrous iron uptake; G and H = Berlin blue.) y

References p . 423-42s

414

N. Y A N A G I S A W A

ef

01.

developed tremor at rest. So far, 22 out of 40 verified autopsied cases of HallervordenSpatz disease in the available literature, including the present two, showed some degree of involuntary movement. This would justify listing the hyperkinetic motor disturbances as characteristic of the disease. Babinski’s sign was present in both of the present examples, as well as in approximately one third of the reported cases. Muscular weakness or atrophy which was manifested in the present examples in the later stages of the disease has also been frequently reported. Though a part of the latter could be attributed to the disease of the cerebellum, it is apparent that the motor disturbances of Hallervorden-Spatz disease are not only restricted to the extrapyramidal system, but a frequent involvement of the pyramidal tract comprises one of the characteristics of the disease. This was verified pathologically in several cases (present case 2 ; Hallervorden, 1924; Kalinowsky, 1927; case K.S. of Eicke, 1940; Netzky et al., 1951). From the symptomatology o f the accumulated familial and sporadic cases up to date, the early proposal of Winkelman (1932) that the ‘pure’ form of the disease shows only rigidity but no pyramidal sign nor involuntary movement, does not fit in with the present concept of Hallervorden-Spatz disease. Kalinowsky’s view (1927) that the motor phenomena are characterized by a combination of spastic spinal paralysis and severe involvement of the basal ganglia, has proved more suitable and comprehensive. Since Hallervorden and Spatz’s original description (1 922) initial and more severe involvement of the lower extremities rather than the upper has been reported in a majority of cases. Thus our two cases, who first developed incoordinative or athetoid movements of the upper extremities are rather exceptional. Actually, the disturbances in the upper limbs were consistently predominant throughout the total course of the illness. In most reported cases, as a rule, impaired gait and spasm or stiffness of the legs occurred as the first motor impairment. Only case K. S. of Eicke (1940), and the cases of Osman and Schiikru (19351, Scharenberg and De Jong (1952) showed speech disturbances such as stuttering as the first physical sign. More severe involvement of the upper extremities than the lower ones in the later stages of the illness was seen only in Case 2 of Zeman and Scarpelli (1958). Some cases showed retarded development of psychic functions before the onset of the illness. This was usually ascribed to congenital mental deficiency, but could be differentiated from the subsequent, progressive mental deterioration resulting from the essential disease process. However, the extent of the psychic disturbance was, as a rule, difficult to determine because in a majority of the cases, in the later stages of the illness, there was no or very little spontaneous speech or emotional expression. This could be primarily due to the severe neurological impairment. The degree of mental deterioration varied in each case. It resulted in high-grade dementia in cases Alma, Friede and Marie of Hallervorden and Spatz (1922). The present two siblings the younger of whom, Case 2, showed congenital mental deficiency, developed psychic deterioration in the subsequent stages of the illness. In this regard it is important to note that case 21 of the Vogts ( I 920) was said to have had no intellectual deficiency, and in the case of Winkelman (1932) no mention of the psychic status at least suggests the absence of considerable mental deterioration.

HALLERVORDEN-SPATZ

DISEASE

41 5

The results of ophthalmoscopic examination deserve mention. Winkelman (1932) described the combination of retinitis pigmentosa with Hallervorden-Spatz disease, while Kalinowsky (1927) mentions temporal pallor of the optic disc in three siblings. All these cases developed night blindness or visual impairment, and both authors considered these findings as essential for the diagnosis. A few subsequent reports mentioned similar findings; temporal pallor of the papilla (Helfand, 1935), certain retinal pigmentation (Vincent and Van Bogaert, 1936), and impaired visual acuity (Wahlstrom, 1946). Both of the present examples, on the other hand, showed pigmentary degeneration of the retina, but had no complaints or signs of visual impairment. It is assumed that retinal degeneration or optic nerve atrophy is not infrequently combined with heredo-degenerative diseases of the nervous system. The available data concerning this point remain insufficient in order to establish their significance in regard to the essential disease process under consideration. It may be assumed that there exists a higher incidence of abnormality in the ocular fundus because ophthalmoscopic examination has been carried out only on small numbers of cases to date. Familial and genetic aspects. In the present report, two sisters developed a similar disease. One brother of I5 is healthy and normal. Twenty-two familial cases of the disease have been reported to date. The victims were all siblings and, interestingly, most of them were of the same sex: 5 females of Hallervorden and Spatz (1922), 3 males of Kalinowsky (1927), 2 males of Winkelman (1932), 2 females of Bini (1952), 3 males of Korney (1964), and 2 females of the present report. Only the cases of Urechia etal. (1950) were 1 male and 1 female, and the cases of Messing (1933) were 1 male and 2 females. The 2 cases of Fischer (1933) were only stated to be siblings. No instance of consanguineous marriage of parents has been reported. There have been no autopsy-verified instances of one family being affected over two generations. It is therefore suggested that the genetic pattern of the disease in many familial cases, including the present ones, may be of the sex-linked dominant type due to gene mutation in the parent. In regard to the more than 20 sporadic cases, detailed information concerning the fate of intact siblings of the probands have not been recorded; thus it is impossible to define the exact genetic pattern of that form of the disease. Morphopathogenetic aspects based on routine stain. Aside from the restricted changes in the wall of the surgical lesions in the pallido-putamen and the thalamus of Case 1, it is difficult to estimate the effect, if any, of the surgical lesions upon the essential disease process. The common pathomorphological features in the basal ganglia of both cases, i.e. operated and non-operated, can be regarded as essential for the disease and consist of the following: Enormous deposition of tiny pigmentary granules in astrocytic cytoplasmic processes, similar globules in phagocytic cells, primarily perivascular deposition of pseudocalcareous concretions and a large number of spheroid structures, as well as preferential occurrence of those lesions in the oral and the internal segments of both pallidi. These features mentioned above correspond well with those of Hallervorden-Spatz disease as reported previously. In the present cases, the spheroids which are one of the essential pathomorphological criteria of the disease, were abundant in the pallidum, to a lesser degree in the adjacent circumscribed areas of both internal capsule and putamen, and much less References p. 423-425

416

N. Y A N A G I S A W A

at

al.

or absent in the substantia nigra. On the other hand, both cerebral and cerebellar cortex lacked spheroids and thus clearly contrasted with the observations in which they were widespread in the entire central nervous system (Hallervorden and Spatz, 1922; Hallervorden, 1924; Helfand, 1935; Eicke, 1940; Bini, 1952; Gross et al., 1957; Seitelberger et al., 1963). In Case 2, a large number of spheroids were found in the gracile nuclei with an excessive deposition of glycogen granules in the parenchyma. The selective vulnerability of the dorsal column in this disease has never been reported before, except for a pallor of the cervical dorsal column in the myelin preparations (Kalinowsky, 1927);and for dernyelination and the conspicuous formation of spheroids in the column of Burdach (Gross et al., 1957) or of Go11 (Seitelberger et a]., 1963) of the cervical cord. We should point out that in our experience, this type of spheroid may preferentially occur in aged brains without any particular CNS disorders (Fujisawa, 1964), certain degenerative CNS diseases such as amyotrophic lateral sclerosis, parkinsonism-dementia complex of Guam, etc. (Shiraki et al., 1965) or occasionally in even younger individuals with certain metabolic disorders, such as the late infantile type of amaurotic idiocy (Shiraki and Fujisama, 1964). Lampert et al. (1964) have recently succeeded in demonstrating similar spheroids in the gracile nucleus in experimental animals with vitamin E deficiency, and claimed, on the basis of electron microscopic examination, that the spheroids come from degenerated neuraxons. The origin of the spheroids in the globus pallidus in Hallervorden-Spatz disease has been disputed since 1922, and it is now commonly accepted that the great majority of them are derived from dystrophic neuraxons (Hallervorden and Spatz, 1922; Eicke, 1940; Seitelberger et d., 1963). In the present cases, the neurofilamentous structures seen in silver preparations were made visible within the spheroids of both pallidum and gracile nucleus, but a picture showing a distinct connection of the running neuraxons with these structures could never be obtained. In this regard, it is interesting to note that the experimentally-induced spheroids of the gracile nucleus (Lampert et al., 1964) preferentially occur at the presynaptic terminals of fine caliber neuraxons, and it may thus be difficult to establish a clear-cut connection with the neuraxons under light microscopy. Another characteristic of Hdflervorden-Spatz disease, namely an exceedingly large number of tiny pigmentary granules in astrocytes, and globules in phagocytic cells in both pallidum and substantia nigra, was beautifully demonstrated in the present cases in which a smaller number of the dark-brownish, intensely iron-positive coarse pigmentary concretions were present without any relationship to certain cellular elements. The latter finding has rarely been described in previous publications. In addition, it is of interest that an excessive deposition of the same types of pigmentary granules or concretions in the pallido-nigral nuclei, as well as of spheroids primarily in the substantia nigra were recently observed in two cases of the parkinsonism-dementia complex in Guam (Shiraki et al., 1965). The accumulation of pigmentary granules in neuronal cells from the brain stem to the cerebral cortex was also described in some cises of this disease (Hallervorden and Spatz, 1922; Fiinfgeld, 1930; Netzky ef a/., 1951 ; Zeman and Scarpelli, 1958; Korney, 1964). The significance of this observation will be discussed below.

HALLERVORDEN-SPATZ

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417

In the present two cases, both demyelination and gliosis of the pallidum were present in its oral and inner portions, as well as caudally in its dorsomedial part along the internal capsule. In the previously reported cases, as a rule, the oral or inner portion was affected (Fischer, 1912; cases 1 and 2 of Funfgeld, 1930; Osman and Schukrii, 1935; Meyer and Earl, 1936; case 2 of Eicke, 1940; Gross et al., 1957). The preferential involvement of the dorsal portion was reported, or is observed in the pictures, in the cases of Hallervorden (1930), Eicke (1940), Bini (1952) and Korney (1964). Finally, Hallervorden (1924) observed a n even distribution from the oral to the caudal portion. Case 2 showed a few differences from Case 1: Focal degeneration and disintegration of the cerebellar cortex, particularly of the Purlunje cell layer; widespread presence of carmine-positive granules in almost all nuclear structures especially in the gracile nucleus where massive axonal degeneration also had occurred. Involvement of the cerebellum, mainly disintegration of Purkinje cells, has been frequently observed in this disease (Hallervorden and Spatz, 1922; Kalinowsky, 1927; Meyer and Earl, 1936; Urechia et al., 1950; Scharenberg and De Jong, 1952; Gross et al., 1957; Zeman and Scarpelli, 1958; Seitelberger et al., 1963). In this regard, it is of interest to note that degeneration of the cerebellar cortex constitutes one of the characteristic findings of the infantile neuraxonal dystrophy (Seitelberger, 1952, 1957; Cowen and Olmstead, 1963), an entity which Seitelberger believes to have a common pathogenesis with Hallervorden-Spatz disease. Morphopathogenetic aspects based upon histochemical studies. The pathogenesis of Hallervorden-Spatz disease still remains unknown and two points of view were recently proposed by Seitelberger (1957), and Zeman and Scarpelli (1958) based upon histochemical characteristics. Seitelberger focused attention on the pathognomonic presence of spheroids and claimed that disturbed intraneuronal metabolism resulted from an accumulation of certain protein products, thus suggesting that the disease was a neuraxonal proteid dystrophy, and that the neurodystrophic process interfered with the specific metabolism of the pallidonigral nuclei and resulted in the excessive localized pigmentation. Histochemical studies in our cases indicated that the spheroids consist mainly of a protein component combined with certain carbohydrates and are similar to those described by Seitelberger and Grass (1957) as well as by Cowen and Olmstead (1963\, although certain differences between the two do exist in regard to compound lipids and mucopolysaccharides (Table JI). Zeman and Scarpelli (1 9581, on the other hand, emphasized the widespread accumulation of lipid granules in nerve cells and proposed that the pigmentary deposits in the pallido-nigral nuclei were essentially derived from the same intraneuronal granules both having the same histochemical properties. They claimed that the basic process underlying the HallervordenSpatz disease is a disturbance of lipid metabolism analogous to cerebral lipidosis. The intraneuronal granules in our cases developed the usual staining properties of socalled ‘lipofuscin’ at a relatively early stage of the maturation process of lipopigmentary metabolism. Furthermore, the pallidal pigments belonged to the category of so-called physiological lipopigments at the different maturity stage as seen in control brains of aged individuals. This conformity was first suggested by Hallervorden and References p . 423-425

418

N. Y A N A G I S A W A

ct al. TABLE

SUMMARY O F HISTOCHEMICAL P R O P E R T I E S OF S P H E R O I D S A N D P I G M E N T A R Y G R A N U L E S IN T H E H A L L E R V O R D E N - S P A T Z VISEASE, O T H E R R E P O R T E D CASES A N D

(-

=

No information; 0

Negative; I

=

~

~

=

Minimal;

~~

~~

Spheroid -

~

~~~~

Globus pallidus Present two cases of Hallervorden-Spatz disease

Lale infantile form of Hallervorden-Spa12 disease *

~~~

~

Homogeneous structures -~

~~

Proteins: Proteins in general Aromatic amino acids Nucleic acids Lipids: Neutral fat Compound lipids

Carbohydrales: Glycogen Mucopol ysaccharides Carbohydrates in firm union with protein or lipid fraction

Other staining properties: Argyrophi lia Argent affinity (Masson-Fontana) Schmorl Acid fastncss Natural color Bleaching with 10% H202 Fe -1- -1 Methylene blue extinction (pH)

+

Pigmcnrary granules

~

Large spheroids

Small to middlesized spheroids

-

~-

~

1+ -311+ - 3 + 0

1 iI I -2$0

2+ 0

2+ 0

0

0

0

0

0- 1+

0- I

11- - 2 1

0

0

2 -1.

I+

0-

It

0

0- I + (very rarely) 0

0- I +

1+ - 2 1

f-21

2+ - 3 + I+ I+ I t -21Yellow to brownish-yellow Partly decolorized 0-1 t 3.20

0

0

0- i *-lt Colorless 0- I+ 3.88

I + -2-t 2 -I -

Faintly yellow

4.93 (isoelectric point)

* Seitelberger el al., 1957. * * Cowen and Olmstead, 1963. 5 Shiraki et al., 1965.

I

HALLERVORDEN-SPATZ

419

DISEASE

I1 G L O B U S P A L L I D U S , S U B S T A N T I A N I G R A A N D O T H E R AREAS O F T H E B R A I N O F T W O CASES O F ALLIED DISORDERS, AND OF CONTROL WITH PARKINSONISM AT

I+

=

Slight; 2+

=

Moderate; 3+

=

73

Y E A R S O F AGE

High)

structures

Pigmentary granules

Mainly posterior horn of spinal cord

Substantia nigra

Infantile neuraxonal* * dystrophy

Parkinsonismdementia complex on Guam5

-

0-2+ 1+ -2+ 0

2+

-

3+

0 0

1+ - 2+ (fixed to protein, probably phospholipids)

0 - 1+ (rarely) 0- I t

Globus pallidus Present two cases Late infantile of Hallervordenform of Spatz disease Hallervorden-Spatz disease

Substantia nigra Control with parkinsonism

Parkinsonismdementia complex on Guam

f

0- f 1+ -2+ 0

f- 2 + 1+ -2+ 0

2+ Reddish brown (Feulgen)

*-I+

0-*

0

It - 2 +

* -2+

k -2+

1+ -2+ 0

1+ 1+

-

0

2 + - 3+

0

0

0

0

0

*-I+

0

0

0

0

1+

1+

0-3+

*

0 - 3-t0-2+ 1+ -2+ f -2+ Colorless or yellow -

0-2+ 3.20

References p . 423-425

0 - 1+

2+ 1+ 2+ 0-3+ 2+ - 3+ 1+-3+ 0-I+ 1+ 0 - 1+ 2+ 1+-3+ 2+ (red) Yellow to Yellow to Yellow to yellowish-brown yellowish-brown yellowish-brown Partly decolorized Partly decolorized Partly decolorized 0-2+ 0-2+ 2+ Below 2.62 - 3.20 3.88 3.20 (isoelectric point)

3+

1+ - 3 +

2+ 2+ 2+ - 3 + 3+ Yellow to yellowish-brown -

0-2+ 2.62

420

N. Y A N A G I S A W A

et a/.

Spatz (1922), and recently confirmed by Seitelberger et al. (1963) by histochemical studies. Aside from certain discrepancies in staining properties and iron reaction, the deposits of pallidal pigments outside nerve cells were so excessive that they cannot be solely derived from disintegrated nerve cells as suggested by Zeman and Scarpelli (1958), for the simple reason that nearly all nerve cells of the pallidum were well preserved in our cases as well as in others. One of the most noticeable discrepancies in the nature of the pigmentary granules between the case of Zeman and Scarpelli (1958) and ours as well as other reported cases is the result of the Bial reaction for neuraminic acid. Zeman and Scarpelli reported a positive reaction both from histochemical and quantitative estimations, while Seitelberger and Gross (1957), Korney (1964) as well as ourselves, obtained a negative reaction. Since case 2 of Zeman and Scarpelli also had hepatosplenomegaly and growth disturbance of long bones, it is conceivable that it might be considered a certain type of cerebral lipidosis coincidental with Hallervorden-Spatz-like lesions. This, however, does not ignore the possible relationship of disturbed lipid metabolism to the pathogenesis of Hallervorden-Spatz disease. Jervis (1952) reported a case which showed thc clinico-pathological feature of amaurotic idiocy, com bined with excessive pigmentary deposition in the pallido-nigral area. The number of intraneuronal granules of lipopigmentary nature in the present cases was quite excessive considering the age of the patients. In addition, the pallido-nigral pigments also included a lipid component. It is therefore permissible to speculate upon the existence of some kind of disturbed lipid metabolism in Hallervorden-Spatz disease. Seitelberger’s thesis on axonal proteid dystrophy requires further comment. He (1957) stated that the abnormal pallidal pigments in the disease are derived, at least partly, from the contents of dystrophic axons, and he explained the absence of pigmentary formations in other parts of the brain as due t o specific local conditions of neuronal metabolism. The possibility that the pigmentary granules in the spheroids are transported by way of astrocytes, or retained by them, must be considered in view of the identical histochemical properties of the granules in both structures. l n other words, the pigmentary granules in both structures may suggest the morphologic expression of a process of assimilation but not a destructive one, since histochemically the granules represent essentially physiological material. If then, spheroids were destroyed, their breakdown products, i.e.coarse pigmentary globules, would be phagocytized in gitter cells and finally gliosis and demyelination would occur. Interesting to note in this regard, an exceedingly large number of glycogen granules were deposited in a conspicuously large number of the spheroids in the reticular zone of the substantia nigra in the two cases of parkinsonism-dementia complex on Guam (Shiraki et al., 1965) of which the histochemical characteristics are summarized in TablclI. At any rate careful histochemical analysis of those spheroids in the future will add to our understanding of the morphopathogenesis of Hallervorden-Spatz disease and allied disorders. Clinico-pathological correlations. To explain clinical manifestations of an extrapyramidal nature, especially dystonia on the basis of brain damage is in most cases a matter of conjecture. Available data on idiopathic dystonia indicate that in most

HALLERVORDEN-SPATZ

DISEASE

42 1

cases the neuronal degeneration took place predominantly in the caudate nucleus o r the putamen (Herz, 1944a,b). On the other hand, the cases of Hallervorden-Spatz disease with dystonia as part of their clinical manifestation, appeared to have a common pathological picture, that is, a rather slight involvement of the substantia nigra. Greater involvement of the globus pallidus than the substantia nigra has been less frequently reported (Hallervorden, 1930; Osman and Schiikru, 1935; Benda, 1949; Onari, 1925; Fiinfgeld, 1930). The former three cases represented dystoniaas physical manifestation. Selective severe pallidal disintegration of both nerve cells and fibers is known to result in pure rigidity, without involuntary movements as in the cases of CO-intoxication etc. Therefore, it seems likely that preservation of the nerve cells of the pallidum is indispensable in order to have dystonia. The involvement of the subthalamic nuclei in the present two cases, with nerve cell degeneration and proliferation of glial nuclei ventromedially in particular, should be taken into consideration. These findings may have a certain relationship to the degenerative changes of incoming fibers from the disintegrated pallidum. Van Bogaert and Scherer (1936) reported the finding of restricted involvement of the pallidum and the subthalamic nucleus, with clinical evidence of typical torsion dystonia. Severe demyelination with gliosis was present in the inner part of the pallidum and the lateral part of the subthalamic nucleus, and approximately two thirds of the pallidal nerve cells were degenerated. No particular description of the pathology of the subthalamic nucleus was found in the previously reported cases of Hallervorden-Spatz disease with dystonia. Definite pyramidal signs, such as exaggerated deep tendon reflexes and Babinski’s sign, were observed during the clinical course of the present two examples, in which Babinski’s sign of Case 1 had actually occurred bilaterally before the operative invasion. The clear-cut demyelination and gliosis in the pyramidal tracts extending from the brain stem to the spinal cord in Case 1 could not be attributed to the surgical lesions involving both internaI capsules. On the other hand, only minimal demyelination of the lateral columns of the spinal cord and minimal to slight disintegration of both anterior and lateral horn cells, as well as a few nerve cells showingretrogtade degeneration occurred in Case 2. Progressive dementia constitutes another characteristic of the disease, and has been explained on the basis of widespread degeneration of nerve cells or axis cylinders (spheroids) in the cerebral cortex. In our cases, mental deterioration did exist but to a lesser degree, although no spheroids or disintegration of cortical nerve cells were encountered. However an abnormal amount of intraneuronal ‘lipofuscin’ was found. Diagnostic criteria derived,from clinico-pathological observations. As far as the main clinical features of the idiopathic Hallervorden-Spatz disease are concerned, the following appear to be essential : progressive rigidity of extremities and trunk with or without involuntary hyperkinetic movements and pyramidal signs ; progressive mental deterioration in most cases ; occasional degeneration of ocular fundi ; familial occurrence of the disease restricted to siblings of the same sex in a single generation or sporadic occurrence of the illness; early onset of the disease, usually in the first decade; and clinical course extending over several years frequently more than 10. In the absence of specific laboratory tests, which are not yet available, the definitive References p . 423-425

422

N. Y A N A G I S A W A

etal.

diagnosis of Hallervorden-Spatz disease must await post-mortem confirmation. There is no doubt that the main sites of the lesions are the globus pallidus and substantia nigra, and constitute the morphologic background for the extrapyramidal motor disturbances. In cases without, or with less severe, involvement of the substantia nigra, hyperkinesis including dystonic movement may occur. In regard to the diagnostic morphological criteria of the disease, it is our opinion that both types of lesion, i.e. pigmentary granules and spheroids in abnormally large numbers, must be present in order to make the diagnosis. These criteria agree with those originally reported by Hallervorden and Spatz (1922). The independent occurrence of only one type of lesion should lead to caution in establishing the definite diagnosis of the disease. The biochemical peculiarities of the granules in the spheroids may also be of use in the differential diagnosis of the disease: a large number of glycogen granules are present in the spheroids of the substantia nigra of the parkinsonism-dementia complex of Guam (Shiraki et al., 1965), while no or very few glycogen granules are present in Hallervorden-Spatz disease. If one accepts the possibility that the granules in the spheroids could be transported and accumulated by way of neurogliopils, then it seems likely that Hallervorden-Spatz disease should be considered a ‘storage’ disease in a broad sense. Tn this regard it is of interest to note that a widespreadaccumulationof lipopigments in cortical neuronal cells could be considered a morphological background for progressive mental deterioration. Although the diagnostic clinico-pathological features of Hallervorden-Spatz disease have been summarized above, confusion still exists for two reasons: (a) Nothing is known in regard to the etiology of the disease; and (b) Both histopathological and histochemical findings in our two cases suggest some similarity with excessive manifestations of the non-specific changes seen in the aged brains. A serious question thus arises as to whether the changes are attributable to an independent clinico-pathological entity, i.e. Hallervorden-Spatz disease or to a non-specific syndrome, i.e. Hallervorden-Spatz syndrome (or status pigmentatus). Not enough data on the basic metabolism of aged brains have been obtained so far, and thus no definite answer is available at the present time. The following cases from the literature developed only a part of the pathological changes of Hallervorden-Spatz disease, mostly iron-positive pigmentary deposits in the pallido-nigral nuclei, while conspicuous pathologic changes related to other disease processes were concurrently present in other parts of the brain: the case of Van Bogaert with postencephalitic parkinsonism or chronic encephalitis (1940); the case of Van Bogaert with neurofibromatosis (1947); cases 3 and 4 of Benda with chronic rheumatic encephalitis (1949); the case of Jervis with atypical amaurotic idiocy (1952); the case of Zeman and Scarpelli with a type of cerebral lipidosis (1958). All these cases would be excluded from the group of Hallervorden-Spatz disease if the above criteria were strictly applied. On the other hand, they would be acceptable if one recognized a gradual transition from Hallervorden-Spatz disease to status pigmentatus or certain storage diseases. A final conclusion must await future observations.

HALLERVORDEN-SPATZ

DISEASE

423

SUMMARY

Two siblings with Hallervorden-Spatz disease, operated and non-operated, were studied clinico-pathologically. The essentially similar clinical pictures of both cases included progressive torsion dystonia with some degree of mental deterioration starting early in the second decade and ending in death within 10 years. The motor disturbances were analyzed by electromyography. Stereotaxic neurosurgery was performed on one case aiming at both thalamic nuclei and globus pallidi. Histopathological examination revealed the characteristic findings of Hallervorden-Spatz disease : an excessive deposition of pigmentary granules in astrocytes and phagocytic cells, along with pseudocalcareous concretions : a conspicuous number of spheroid structures of dystrophic neuraxonal origin; demyelination and gliosis of a moderate to high degree. All these findings were localized bilaterally in the globus pallidus, and less intensely in the reticular zone of the substantia nigra. Lipopigmentary granules were also increased in the neuronal cytoplasm of the entire gray substance from the cerebral cortex to the brain stem. Histochemical studies revealed that the above-mentioned pigmentary granules in different structures were identical with physiological pigments at different stages of maturity in the aged brains. The spheroid structures contained proteinaceous substances combined with certain carbohydrate moieties. Based upon published data, the different aspects of Hallervorden-Spatz disease, i.e. clinico-genetic, morphopathogenetic, especially relating to disturbed protein and lipid metabolism, diagnostic criteria and clinico-pathological correlation, are discussed. ACKNOWLEDGEMENT

The authors wish to express their appreciation to Dr. C. M. Poser, Professor and Head, Division of Neurology, University of Missouri School of Medicine, Kansas City, Mo. (U.S.A.)for his kind assistance in the preparation of the manuscript. REFERENCES BENDA,C., (1949) ; Chronic rheumatic encephalitis, torsion dystonia and Hallervorden-Spatz disease. Arch. Neurol. Psychiat. (Chic.), 61, 137-163. BINI,L., (1952); Sul valore dei reperti istopathologici per la nosographia della malattia di Hallervorden e Spatz. Proc. First b t . Congr. Neuropathol. (Rome, Sept. 8-13, 1952). Vol. 3. Torino, Rosenberg and Sellier (pp. 90-100). E. V., (1963); Infantile neuroaxonal dystrophy. J. Neuropath. exp. COWEN,D., AND OLMSTEAD, Neurol., 22, 175-236. D., (1962); The Basal Ganglia and their Relation to Disorders of Movement. London, DENNY-BROWN, Oxford University Press. DIEZEL, P. B., (1957); Die Stoffwechselstorungen der Sphingolipoide. Berlin, Springer. EICKE,W.-J., (1940); Neue Beobachtungen iiber die Hallervorden-Spatzsche Krankheit. Arch. Psychiat. Nervenkr., 111, 514-546. FISCHER, O., (1911); Zur Frage der anatomischen Grundlage der Athetose double und der posthemiplegischen Bewegungsstdrung uberhaupt. Z . ges. Neurol. Psychiat., 7 , 463-486. O . , (1933); Zur Histopathologie der degenerativen Erkrankungen des ZentralnervenFISCHER. systems. Munch. med. Wschr., 80, 202. FUJISAWA, K., (1964); Axonal dystrophies in the gracile nucleus in the medulla oblongata among general necropsied materials. Fifth Cungr. Jap. Neuruputhol. SOC.,In press.

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N . Y A N A G I S A W A et

al.

FUNFGELD, E., (1930); Zur Klinik der Pathologie friihkindlicher, das striare System bevorzugender, Hirnerkrankungcn. J . Psychol. Neurol., 40, 85-98. GROSS,H., KALTENBACK, E., U N D UIHEHKAK, B., (1957); Uber eine spatinfantile Form der Hallervorden-Spatzschen Krankheit. I. Mitteilung : Klinisch-anatoniische Befunde. Dtsch. Z . Nervenheilk., 176, 77-103. HALLF.RVORD~N, J., (1924); Uber eine faniiliare Erkrankung im extrapyramidalen System. Drsch. Z . Ner venheilk., 81, 204-2 10. HALLERVORDEN, J., (1930); Athetose mit eigenartigem pathologisch-anatomischem Befunde. Zbl. ges. Neurol. Psychiat., 56, 144. HALLERVORDEN, J., UND SPATZ,H., (1922); Eigenartige Erkrankung ini extrapyramidalen System mit besonderer Beteiligung des Globus pallidus und der Substantia nigra. Z . ges. Neurol. Psychiat., 19, 254-302. HELYANI), M., (1935); Status pigmentatus. Its pathology and its relation to Hallervorden-Spatz disease. J . new. m n t . Dis., 81, 662-675. HERZ,E., (1944a); Dystonia. I. Historical review; analysis of dystonic symptoms and physiologic mechanisms involved. Arch. Neurol. Psychiar. (Chic.), 51, 305-3 18. HERZ,E., (1944b); Dystonia. 111. Pathology and conclusions. Arch. Neurol. Psychiat. (Chic.), 52, 20-26. HIRANO, A., A N D ZIMMERMAN, H. M., (1962); Silver impregnation of nerve cells and fibers in celloidin sections. Arch. Neurol., 6, 114-122. HOEEER, P.F.A . , A N D PUTNAM, T. J., (1940); Action potentials in athetosis and Sydenham’s chorea. Arch. Neurol. Psychiat. (Chic.), 44,517-531. JERVIS,G. A., (1952); Hallervorden-Spatz disease associated with atypical amaurotic idiocy. J . Neuropath. exp. Neurol., 11, 4-18. KALINOWSKY, L., (1927); Familiare Erkrankung mil besonderer Beteiligung der Stammganglien. Mschr. Psychiat. Neurol., 66, 168-190. K ~ R N E ST., Y , (1964); Die Stoffwechselstorungen bei der Hallervorden-Spatzschen Krankheit. Arch. Psychiaf. Nervenkr., 205, 178-191. LAMPWI.,P., BLUMBOI
HALLERVORDEN-SPATZ

DISEASE

425

SHIRAKI, H., HIRANO,A., LESSELL, S., AND KURLAND, L. T., (1965); Neuropathologic studies of two cases of the Parkinsonism-dementia complex on the Island of Guam. In press. URECHIA, C. I., RETEZEANO, A., ET MALLER, O., (1950); La maladie de Hallervorden-Spatz. Deux cas de rigidite progressive farniliale avec un examen anatomique. Enckphale, 39, 197-219. ‘JAN BOGAERT, L., (1940); Associations anatomo-cliniques: degenerescence pigmentaire pallidonigrique (Hallervorden-Spatz) et encephalite lethargique chronique. Rev. neural., 72, 448-456. VANBOGAERT, L., (1947); Sur une affection heredo-familiale apparentee a la maladie d’HallervordenSpatz et aux atrophies cerebelleuses, caracterisee par un syndrome cerebellomyoclonique evoluant lentement et tardivement vers un etat rigide au cows d’une neurofibromatose. Mschr. Psychiat. Neurol., 113, 183-214. VANBOGAERT, L., UND SCHERER, H.-J.,(1936); Zur Frage der Beziehungen von Pallidum und Kleinhirnlasionen zum Syndrom der Drehbewegungen um die Korperachse. Mschr. Psychiat. Neurol., 93, 140-165. VINCENT, C., ET VAN BOGAERT, L., (1936); Contribution a l’etude des syndromes du globe plle. La degenerescence progressive du globe pile et de la portion reticulee de la substance noire. Rev. neurol., 65, 921-959. VOGT,C. U N D O., (1920); Zur Lehre der Erkrankungen des striaren Systems. J . Psychol. Neurol., 25, 627-826. W A H L S T R ~A,, M , (1946); Fall av sallsynt extrapyramidal rubbning. Hallervorden-Spatz’ sjukdom. Svenska Lak.-Tidn., 43, 1832-1838. Excerpta Medica, Sect. VIII, 1, 34. WINKELMAN, N. W., (1932); Progressive pallidal degeneration: A new clinicopathologic syndrome. Arch. Neurol. Psychiat. (Chic.),27, 1-21. ZEMAN,W., AND SCARPELLI, D. G., (1958); The nonspecific lesions of Hallervorden-Spatz disease A histochemical study. J. Neuropath. exp. Neurol., 17, 622-630.

426

Author Index * Abe, K., 208, 335 Abe, M., 85 Achslogh, J., 332 Adams, J., 341 Adey, W. R., 48, 341 Akazome, T., 66,71 Akert, K., 40, 109, 113, 127 Akimoto, H., 208-229 Akiyama, Y., 206 Albee, G. W., 332 Albe-Fessard, D., 348 Albrink, M. J., 82 Allen, M. F., 40 Aniassian, V. E., 58 Ando, N., 215 Andy, 0. J., 330 Antone, G., 151, 152, 177 Araki, S., 184, 190 Archibald, D., 109 Arduini, A., 61 Arfcl, G., 348 Ariizumi, S., 278 Arima, A., 270, 272, 274 Ariyasu, T., 193 Aserinsky, E., 109 Austin, G. M., 334 Aycrs, F. W., 85 Azunii, K., 226 Bailey, P., 347 Baird, H. W., 341 Baltzan, M. A,, 278 Balvin, R., 340 Ban, T., 355 Banu, E., 177 Barker, D., 147 Barlow, J., 203 Barnes, S., 157 Bearn, A. G., 271, 274 Beattie, J., 358 Bein, H. J., 147 Benda, C., 373,413,421,422 Bender, L., 289 Bengochea, F. G., 352 Berg, J. J., 37 Berger, F. M., 134 Berlucchi, G . , 61, 246 Bertrand, G., 348

*

Bertrand, I., I77 Bickford, R. G., 128 Bidder, T. G., 352 Bini, L., 415-417 Blake, H., 123 Blumberg, J . M., 389 Bogdanski, D. F., 203 Bond, D. D., 352 Bowsher, D., 334 Bradley, P. B., 113 Bravo, G., 339 Britton, S. W., 253 Brookhart, J. M., 59, 60 Brow, C. R., 358 Bruell, J. H., 332 Bruland, H., 127, 134 Burgemeister, B. B., 1 Buzzard, F., 178, 179 Candia, O., 93, 246, 248, 253 Cannon, W. B., 253 Chan-Nao Liu, 124 Chang, H.-T., 55, 57 Chikazawa, S., 124 Choroschko, W. K., 1 Chungcharoen, D., 262 Cier, A., 257 Clark, S. L., 126 Cobb, W. A., 109,331 Cole, J., 333 Collier, J., 178, 179 Connell, P. H., 192 Cooper, 1. S., 339 Cowen, D., 389, 417,418 Cummings, J. N., 270 Dahl, N., 253 Daly, M. de B., 262 Das, P. K., 49 David, M., 334 Davidson, J. M., 110 Davis, L., 346 Dejerine, J., 333 De Jong, R., 413, 414, 417 D e la Torre, O., 352 Dell, M. B., 334 Dement, W., 61, 109, 123, 208, 226,265 Dempsey, E. W., 340

Italics indicate the pages on which the paper of the author in these proceedings is printed.

A U T H O R INDEX

Denny-Brown, D., 270, 276, 413 Derbyshire, A. J., 126 Dow, R. S., 347 Dusser de Barenne, J. G., 334 Earl, C. J. C., 413, 417 Eccles, J. C., 141, 243, 244 Ectors, L., 332 Edinger, L., 151 Eicke, W. J., 411, 414, 416, 417 Eldred, E., 146 Elkes, J., 113 Endo, S., 215 Esquivel, O., 352 Eto, M., 1-39 Everett, J. W., 41, 90, 91, 109 Ezoe, T., 192, I94 Favale, E., 61, 93, 246, 248, 253 Feath, W. H., 330 Fee, A. R., 109 Fehr, H. U., 147 Feldberg, W., 40 Feldman, R. G . , 82 FernAndez, J. C., 352 Fischer, O., 415, 417 Fisher, C., 226, 265 Fisher, G., 128 Flanagan, M., 341 Fleischhauer, K., 40 Foerster, O., 334 Forbes, T., 126 French, L. A,, 85, 332, 334 Fujii, T., 335 Fujimi, S., 81 Fujimori, M., 208-210, 215, 217, 219-225 Fujisawa, K., 389, 416 Fujishima, M., 83 Fujita, H., 205 Fujiwara, T., 192, 193 Fujiya, Y., 220 Fukiyama, K., 83 Fukuhara, T., 126 Fukushima, Y., 1 Fulton, J. F., 333 Funatogawa, S., 201-203 Funfgeld, E., 273, 413, 416, 417, 421 Camper, E., 333 Gassel, M. M., 231 Geiger, A., 281 Gerard, R. W., I23 Giaquinto, S., 61, 231, 237 Giarman, N. J., 49 Gibbs, E. L., 40, 109, 123, 215 Gibbs, F. A.,40, 109, 123,215 Giussani, A., 61, 93, 246, 248, 253 Givre, A., 340-342 Glees, P., 333

Gloor, P., 48 Goldberg, I. D., 64 Goldstein, K., 151, 152, 179 Gootz, E., 416-418, 420 Gore, I., 64 Goto, A., 1, 192 Goto, T.. 193 Granit, R., 141, 146, 346 Grant, F. C., 334 Green, J. D., 40, 41, 48, 91 Greulich, W. W., 3 Greville, G. D., 109 Gros, C., 334 Gross, H., 41 I , 416-418,420 Grundfest, H., 55 Guillain, M. G., 177 Guiot, G., 348

Hada, H., 194 Hallervorden, J., 373, 411, 413417,420-422 Hara, T., 61 Harowitz, F., 270 Harrer, G., 1 Hassler, R., 339, 343 Hathaway, S. R., 84 Hattori, I., 86, 180 Hayashi, A., 217, 220, 222, 223 Hecaen, H., 334 Helfand, M., 415, 416 Helweg, H., 150, 151, 157, 158, 177, 178 Henatsch, H.-D., 141 Hendley, C. D., 134 Henneman, E., 334 Heppenstall, M. E., 109 Herz, E., 413, 421 Hess, R., Jr., 109, 113, 127 Hess, W. R., 350, 352, 358 Hetzel, H., 1 Hiller, W. F., 332 Hilliard, J., 109 Himwich, H. E., 49, 279 Hirai, S., 269-284 Hirai, T., 215 Hirano, A., 409,416, 418,420,422 Hirano, S., 202 Hirao, T., 196, 200, 265 Hirota, Y.,66 Hoefer, P. F. A., 413 Holmes, G., 175 Holmes, R. L., 262 Holmgren, B., 146 Holmqvist, B., 253, 264 Hongo, T., 340, 341, 343,413 Hori, N., 124 Horie, A., 64 Horie, T., 124 Housepian, E. M., 340 Hudson, C. H., 347 Hukuhara, T., 248

427

428

AUTHOR INDEX

Ihda, S., 1-39 Imai, T., 64 lmamura, G . , 126, 134, 139 Imaniura, Y., 183, 231, 237 Indo, T., 85 Ingvar, D. H., 253,264 Inosc, T., 277 Inouye, E., I 39 Ishikawa, M., 205 Ishikawa, T., 40-53 Ishiyama, J., 40-53 Tto, Y . ,81 Iwaki, K., 220 Iwama, K., 54-63 Iwamiira, Y., 231, 237, 246 Izawa, S., 1-39 Izawada, S., 1-39

Kodama, H., 85 Koella, W. P., 109, 113, 127 Koya. E., 210, 215 Korney, St., 413, 415-417, 420 Krause, D., 246,248 Kristenson, A., 76 Krynauw, K.A., 332 Kubota, K., 147. 231, 237, 246,339 349,413 Kuhnel, H., 246,248 Kumagai, H., 126 Kiirihara, M., 220 Kurland, L. T., 64, 183, 190, 416, 419, 420, 422 Kuroda, M., 85 Kuroiwa, Y . , 85, 183-191 Kurotsu, T., 358 Kuru, M., 334 Kusaka, H., 180

Jacobson, D., 109 Jasper, H. H., 113, 348 Jervis, G. A., 420, 422 Jimbo, M., 226 Jimbo, S., 226 Jinnai, D., 341 Jo, K., 352 Johnson, D. R., 332 Jouvet, D., 265 Jouvet, M., 61, 108, 123, 230,246,248,253, 257, 265

Laine, E., 334 Lambert, E. F., 126 Lampert, P., 389, 416 Larramendi, M. H., 331 Lessell, S., 416, 418, 420, 422 Lcwis, J. T., 253 Liberson, W. F., 40 Lim, R. K. S., 124 Livingston, R. B., 232 Long, C. N. H., 358 Lorcntc dc Nb, R., 237 Lynes, T. E., 134

Kaada, B. R., 127, 134 Kada, M., 1-39 Kalinowsky, L., 413-417 Kaltenbdck, E., 41 I , 416 Kameyama, M., 77 Kaniidc, H., 1-39 Kanematsu, S., 91, 109 Kanrow, E., 246, 248 Kadan, M., 151, 151 Kasamatw, A., 29 Katayama, Y . , 180 Kato, N., 192. 194 Katsuki, S., 64-89 Katsiita, S., 40-53 Kattwinkel, W., 150, 152, 157, 179, I80 Kawai, J., 244 Kawakami, M., 90-112 Kawamoto, T., 54-63 Kawamura, H., 126, 134, 136, 139, 265 Kazamatsuri, H., 220, 224, 225 Kennard, M. A., 333 Khazan, N., 95, 109 Kido, R., 109, 113-149, 253 Kikuchi. S., 220, 224, 225 Kikuchi, T., 134 Kirman, B. H., 37 Kitani, T., 277 Klcitman, N., 109, 123, 208 Kobayashi, T., 40-53, 113

Magoun, 13. W., 108, 334 Malhotra, C. I-., 49 Maller, O . , 41 I , 415, 417 Mano, H., 109 Marchiafava, P. L., 231 Marinesco, G., 152, 178 Marshall, C., 330 Martin, R., 13 Masahashi, K., 208 Masaki, T., 1-39 Masuda, S., 157 Matake, H., 64 Matsushita, A., 113-149 Matsuzaki, M., 257 Mayer-Gross, W., 1 McAlpine, D., 184, 190 McCartney, M., 205 McFie, J., 332 McKinley, J. C., 85 McLean, J. R., 205 Merton, P. A., 146 Messing, Z., 415 Meyer, A., 413, 417 Meyer, M., 352 Meyer, M. J., 85 Meyer, P., 151, 177, 17X Michel, F., 123 Mild, D., 109

AUTHOR INDEX

Minakawa, M., 373-425 Mitchell, S. A., 226 Mine, R., 279 Miura, K., 183 Miyagawa, K., 184, 190 Moeli, P., 152, 178 Moffitt, R. L., 124 Monnier, M., 134 Moriguchi. N., 196 Morin, F., 40 Morishita, H., 1-39 Morrison, R., S., 340 Moruzzi, G., 246 Motozato, Y., 74 Mott, F. W., 152, 157, 179 Mounier, D., 257 Mountcastle, V. B., 334 Moussatche, H., 263 Mozai, T., 269-284 Murayama, S., 113 Muto, Y., 281 Nagae, K., 85 Nagao, T., 340, 341, 343 Nakagawa, S., 21 5 Nakagawa, T., 208 Nakagawa, Y., 219 Nakajima, I., 113, 126 Nakamura, Y., 109, 136, 208, 265 Narabayashi, H., 339-349, 373425 Nauta, W. J. H., 48, 352, 353, 364 Negoro, H., 90, 91 Neil, E., 262 Netzky, M.G., 413, 414, 416 Neumaier, C. L., 150, 152, 157, 179, 180 Newman, P. P., 262 Nicolesco, J., 177 Nielsen, 3. M., 332 Niimi, Y., 231, 237, 246 Nishimoto, A., 341 Noguchi, T., 220 Noica, D., 177 Nomura, S., 147 Norton, S., 200 Obersteiner, H.. 150-1 52, 160, 167, 177 Obrador, S., 331 Ogawa, T., 153 Ogihara, K., 277, 278 Ohye, C., 340, 341, 343 Okabe, K., 208 Okamoto. M., 150-152 Okinaka, S., 183-191, 269, 271-273, 277 Okurna, T., 109, 208-229 Olmstead, E. V., 389, 417, 418 Omae, T., 66, 83, 85 Omura, I., 279 Onari, K., 413, 421 Orrego, F., 62

Oscarsson, O., 347 Oshima, T., 147 Osman, M., 413,414, 417 Osuga, T., 202 Otsuka, H., 64 Ozorio de Almeida, M., 263 Papez, J. W., 350 Parkes, A. S., 109 Parmeggiani, P. L., 55, 61 Patton, H. D., 58 Pearse, A. G. E., 400-403, 409, 411 Pentschew, A., 389 Pepeu, G., 49 Peyton, W. T., 334 Pick, A., 152 Pitres, A., 333 Poggio, G. F., 330 Pollak, F., 151 Polley, E. H., 62 Pollock, L. J., 346 Pompeiano, O., 61, 23 I , 237 Porter, R., 241 Powell, T. P. S., 334 Preston, J. B., 134 Price, J. C., 1 Pundlik, P. G., 49 Purpura, D. P., 55, 340 Putnam, T. J., 1, 413 Pyle, S. I., 3 Quensel, F., 334 Rand, R. W., 341 Randall, L. D., 134 Randt, C. T., 352 Ranoshoff, A., 151, 152, 177, 178 Rechtschaffen, A., 226 Reinhold, G., 151, 152 Rempel, B., 126 Renshaw, B., 237 Retezeano, A., 411, 415, 417 Rheinberger, M. B., 113 Richer, C., 263 Riechert, T., 339 Roffwarg, H. P., 265 Rorschach, H., 289 Rosen, I., 347 Rossi, G. F., 61, 93, 246, 248, 253 Rowland, V., 352 Russell, R., 152, 157, 179 Sadanaga, Y., 40-53 Sager, O., 334 Saller, K., 13 Salvi, G., 246 Samson, F. E., Jr., 253, 264, 281 Sano, K., 350-372 Sasaki. H., 205 Sasaki, K., 210, 220, 244

429

430

A U T H O R INDEX

Sasaki, S., 113 Sawyer, C. H., 41, 90,91, 93-95, 101, 109, 110 Sayer, G. P., 128 Scarpelli, D. G . , 373,413,414,416,417,420,422 Scars, T. A., 331 Schaltenbrand, G., 347 Scharenberg, K., 413,414, 417 Scherer, H.-J., 421 Schlag, J., 340 Schmidt, R. F., 243, 244 Schuell, H., 84 Schukru, J., 413, 414, 416 Schwartz, L., 151-153, 158, 160 Schweitzer, A., 262 Seitelberger, F.,373, 416-418, 420 Sekiguchi, A., 109 Sckignchi, M., 208, 209, 215, 219 Sctchenow, J., 263 Sheehan, D., 333 Shellshear, J. L., 76 Sherlock, S., 278 Shikata, T., 274 Shimamurd, M., 232 Shimazono, J., 183 Shimazono, Y., 124 Shimazu, H., 142, 144, 340-342, 347, 411 Shiniizu, T., 196, 202 Shinagawa, F., 85 Shiraki, H., 183. 184, 190, 278, 373-425 Shiramizu, S., 335 Shiratsuchi, K., 81 Shozuka, H., 124 Simpson, D. A., 352 Skoglund, S., 144 Sofue, E., 305 Somogyi, I., 61, 231, 237 Spatz, H., 373, 411, 414-417, 420, 422 Spiegel, E. H., 341 Spiller, W. C . , 152, 157, 179 Spiro, D., 373, 413, 414, 416 Sprague, J. M., 352 Starzl, T. E., 334 Steg, C.. 141, 346 Strata. P., 61, 246 Succo, G., 61 Sugiyama, Y., 333 Sumita, K., 85 Suwa, N., 184, 190 Suzuki, J., 226, 289 Suzuki, Y., 220 Swann, H. G., 40 Swett, J. E., 237 Szckely, E. G., 341 Taen, S., 220, 224, 225 Takagi, N., 257 Takahashi, Y., 226 Takahashi, Z . , 280 Takano, R., 215

Takano, S., 66, 194, 195 Takeya, S., 66 Takuma, T., 1-39 Talairach, J., 334 Tamari, K., 64 Tanaka, K., 83 Tasaki, I., 62 Tatetsu, S., 192, 193 Tateyama, K., 1 Taverner, D., 143 Taylor, C. W., 334 Tejada, C., 64 Terasawa, E., 90, 91 Thalbitzer, S., 151, 152, 157-159 Thesleff, S., 144 Thompson, C. N., 364 Thurel, R., 177 Tofukuji, C., 5 Tokizane, T., 113, 126, 128, 130, 134, 139, 142, 147, 230-268, 347 Tokuda, T., 224 Tokuda, Y., 220,225 Tomonaga, H., 74 Torii, H., 208 Torii, S., 265 Tower, S. S., 333 Toyoda, J., 220 Toyokura, Y., 183 Tredgold, A. F., 152, 157, 179 Tsubaki, T., 183 Tsukiyama, K., 279 Uchinuma, Y., 215 Udenfriend, S., 203 Ueki, K., 285-338 Uiberrack, B., 411, 416 Umbach, W., 352 Umegaki, M., 1-39 Urechia, C. I., 41 1, 41 5, 417 Utena, H., 1Y2-207 Uzawa, H., 81, 83 Valtax, J.-L., 256, 257 Van Bogaert, L., 413, 415, 421, 422 Verhaart, W. J. C., 333 Vianna Dias, M., 263 Vieta. R., 352 Vincent, C., 413, 415 Vogt, C., 41 I , 413, 414 Vogt, O., 41 I , 413, 414 Von Bechterew, W., 150-152. 160, 177, 178 Von Creuzfeldt, O., 48 Von Dydinsky, L., 151, 179 Von Economo, C., 265, 364 Von Monakow, C., 333 Wada, T., I Waelsch, H., 1 Wahlstrom, A., 413, 415

AUTHOR INDEX

Walker, A. E., 330, 334 Walker, J. W., 1 Wall, P. D., 243 Walter, R. D., 341 Walter, W. G., 109 Ward, J. W., 126 Warner, W. A., 330 Watanabe, H., 271, 279 Wechsler, D., 332 Weissbach, H., 203 Weisscheidel, E., 151 Westman, A., 109 Wheatley, M. D., 358 White, R. P., 253, 264 Whitlock, D. G., 334 Whitteridge, D., 109 Willis, W. D., 243, 244 Wilson, S. A. K., 335 Winkelman, N. W., 373,414, 415 Winters, W. D., 109 Wolpert, E. A., 226 Wolstencroft, J. H., 262 Woods, A. H., 183 Wycis, H. T., 341 Yagi, M., 196 Yamaguchi. N., 208

43 1

Yamakawa, S., 152, 157, 169, 179 Yamamoto, K., 109, 113-149, 246, 253 Yamasaki, S., 281 Yamauchi, N., 276 Yanagida, T., 109 Yanagisawa, N., 340-342,373-425 Yanagisawa, Y., 124, 142, 144 Yokoi, S., 206 Yokota, S., 113, 126, 128 Yoshida, K., 90 Yoshida, M., 340-342 Yoshida, T., 279 Yoshikawa, M., 183, 269-284 Yoshioka, M., 136 Yuasa, S., 202 Yuhara, A., 215 Zanchetti, A., 59, 60 Zanocco, G., 61 Zeman, W., 314, 373,414, 416, 417, 420,422 Ziehen, Th., 151-153 Zimmerman, F. T., 1 Zimmerman, H. M., 373,409,414,416 Zingerle, H., 151, 152, 177 Zollinger, R., 332 Ziilch, K. J., 333

432

Subject Index Acetylcholine, and hippocampus, aftcr-discharge, 47, 49, 50, 52 Ammonia, toxicity, and neuropsychiatric disturbances, 279, 280 Amygdaloid nuclei, and hippocampus, after-discharge, 42, 43, 48 Ataxia, and muscle relaxants, mode of action, 142, 143-147 and muscle spindle, acitvity, 144-147 pharmocological analysis, 141-147 Atropine, and hippocampus, after-discharge, 47-49, 52 Behavior, adaptive mechanism, and methamphetamine, 196-20 1 aggressive -, and reticular system, lesion, 353 and stereoencephalotomy, sedative -, 350371 attent ion react ion, and chlordiazepoxide, 131 and meprobamate, 131 and phenobarbital-Na, 134 and reserpine, I3 1 changes, and brain constituents, 202, 203 and brain, scrotonin levels, 203-206 and chlorpromazine, analysis, 131 threshold elevations, 131 and methamphetamine intoxication, 192206 neurochemical correlates, 192, 193, 201-203 and methamphetamine intoxication, 201203 and chlorpromazine, stimulation threshold, 133 and CNS depressants, analysis, 129-141 and meprobamate, stimulation threshold, I33 and methamphetamine intoxication, 192-206 and phenobarbital-Na, stimulation threshold, I33 responsive activity, and methamphetamine, 196-201 Brain, and drug effects, analysis, 1 13-147 hydrate, bovine, and mental retardation, 1-39 selection of co-twins, 2

methamphetamine intoxication, and behavior, 192-206 serotonin, distribution, and behavior changes, 203-206 and methamphetamine, 204, 205 Catecholamine, metabolism, and cerebrovascular disease, 85, 86 Cerebrovascular disease, angioarchitectural aspects, 73-78 angiographic findings, 84 and blood coagulation, 81 and cardiovascular status, 80, 81 and catecholamine metabolism, 85, 86 and cerebral atherosclerosis, 71-73 and cerebral circulation, 83 clinical aspects, 78-87 clinical diagnosis, 79 cross-sectional examinations, 67 epidemiology, 64-70 incidence, and hypertension, 68-70 and lipid profile, 81, 82 neurophysiological studies, 82, 83 population survey, 66, 67 precipitating factors, analysis, 68-70 predisposing factors, 70-78 psychometric tests, 85 rehabilitation, 86, 87 and speech disorders, 84, 85 studies, 64-88 Chlordiazepoxidc, and behavior, attention reaction, 131 and EEG, pattern, 131 acute cat, 135, 136 chronic cat, 135, 136 and hippocampus, after-discharge, 46, 52 Chlorpromazine, and amygdaloid, after-discharge, 43-45 and behavior, stimulation threshold, 133 and EEG, arousal reaction, 130, 132 pattern, 130-1 32 species specificity, 137, 138 and hippocampus, after-discharge, 43, 47, 49, 52 and hypothalamus, activating system, 134 stimulation thrcshold, 140 and reticular formation, activating system, I34 and sleep,

SUBJECT INDEX

human -, cycle pattern, 220 nocturnal pattern, narcolepsy, 226 CNS depressants, analysis, and behavior, 129-141 and EEG, 129-141 and EEG, acute, cat, 135, 136 arousal reaction, 130 chronic cat, 135, 136 and hypothalamus, activating system, 134 and reticular formation, activating system, 134 Consciousness, levels, and EEG, chronic cat, 120, 122, 126, 127 Copper, histochemical distribution, and liver cells, 273, 274 metabolism, and hepatolenticular degeneration, 271-274 Demyelination, diseases, and brain tissue, extracts, 1 diagnostic categories, 186, 187 etiology, hypotheses, 183-190 Dystonia, attacks, Hallervorden-Spatz disease, 373-378,413,421 EEG, acute cat, and chronic cat, comparison, 123, 127, 128 and CNS depressants, 135, 136 and dogs, comparison, 124, 125 and nictitating membrane, activity, I 17119, 122 normal -, cortical and subcortical leads, 115-1 17 stages, 114, 115, 125, 126 after-reaction, and behavioral arousal thresholds, 94, 95 and caudate nucleus, 95, 97, 98 episodes, and copulation, 102, 103 and distribution, 100-105 and estrogen, implanted, 103, 104 and ovulation, 100-103 and progesterone, implanted, 105 and frequency, analysis, 94-99 and frontal cortex, 95, 98 and hippocampus, 97, 99 and hypothalamic-hypophyseal activity, 90-1 11 and limbic cortex, 95, 97, 98 and midbrain, reticular formation, 97 and olfactory bulb, 97, 99 and sleep, paradoxical, 9 1-94 arousal reaction, and chlorpromazine, 130, 132 and CNS depressants, 130 and hypothalamus, activating system, 138, 139-141

433

and morphine, species specificity, 138, 139 and phenobarbital-Na, 131, 134 and reserpine, 131 and reticular formation, activating system, 138-1 4 1 chronic cat, and CNS depressants, 130, 135, 136 and consciousness, levels, 120, 122, 126, 127 normal -, analysis, 123 monkey, classification, 125 pattern, acute cat, and chlordiazepoxide, 135, 136 and chlordiazepoxide, 131 and chlorpromazine, species specificity, 137, 138 chronic cat, and chlordiazepoxide, 135, 136 dissociation, and chlorpromazine, 130 and meprobamate, 131 and species specificity, drug effects, 138 substages, and sleep, paradoxical -, 93, 94 Electroencephalography, and CNS depressants, analysis, 129-141 Electromyography, recording, oscillography, 340, 345 Emotion, balance theory, and animal experiments, 370 disorders, and ergotropic circuit, 350 and sedative operations, 350-371 mechanism, working hypothesis, 350 Epilepsy, focal -, and sleep, human nocturnal -, 225 and hypothalamotomy, autonomic changes, 364,365, 368 personality changes, and fornicotomy, 352, 353 seizure discharge, and sleep activation, 222 Ergotropic circuit, prosencephalon, and emotion, disorders, 350, 351 Ergotropic zone, hypothalamus, and emotion, 350 Extrapyramidal disorders, stereotaxic surgery, 339-349 Extrapyramidal symptoms, and thalamus, areas, functional role, 347, 348 Fornicotomy, considerations, 352, 353 post-operative changes, 352 technique, 352 Galvanic skin response, changes, 21 3 Globus pallidus, Hal lervorden-Spatz disease, microscopic findings, 387-391, 397

434

SURJECT INDEX

GSR, see Galvanic skin responsc

and autonomic nervous system, post-operative course, 302-305 brain structures, microscopical findings, 3 10-

Hallervorden-Spatz disease brain structures, microscopic findings, 391-393, 397-399 pigmentary granules, histochemical reactions, 405-41 1 clinical features, 374-378, 393, 394, 41 1-415 clinico-epidemiological features, 373 diagnostic criteria, 421, 422 electromyographic findings, 378-382,394,395,

and cerebral functions, preservation, 285-336 and endocrine system, post-operative findings,

318, 321, 323-329

413,

globus pallidus pigmentary granules, 387, 397, 416, 420 pseudocalcareous concretions, 387, 397 spheroid structures, 388-390, 397, 415, 416 components, 3 9 9 4 0 5 histochemical findings, 399-41 I histological changes, 373 microscopic findings, 384-393, 397-399 morphopathogenetic aspects, 41 5-420 nerve cells, pigmentary granules, lipopigmentary metabolism, 41 1 neuropathologic features, 382-399, 413, 414 ophthalmoscopic examination, 375, 393, 41 5 pat hogcnesis, and infantile neuraxonal dystrophy, 417 and lipid metabolism, 4 1 7 4 2 0 and protein metabolism, 417-420 pigmentary granules, and iron metabolism 409

and psychic functions, 375, 378, 393, 394,414 spheroid structures, and axonal degeneration, 373, 416 and iron metabolism, 405 studies, 3 7 3 4 2 3 Helweg, human triangular tract, studies, 150-1 80 Hemiplegia, infantile, autopsy findings, 309-31 8, 323-328 clinical symptoms, 285, 286, 309, 321 and deep sensation, 300 and discriminative sensation, 300-302 and EEC, characteristics, 286 and emotional instability, 286, 309, 321, 331 histological changes, 287, 288, 305-309, 3 19-322

motor function, pre-operative findings, 293295

neurological findings, 286, 309, 321 and pain sensation, 300 psychological testing, 286, 331, 332 seizure incidence, pre-operative, 286,309, 321, w330

tactile sensation, 299 and temperature sensation, 300 Hemispherectomy,

304, 305

metabolism, tests, 302, 303, 335 microscopic examination, method, 310, 323 motor function, follow-up tests, 295-299 post-operative findings, 295-299, 332-334 post-operative course, 286-289 and pubertas praecox, 305, 335 readmission studies, EEG findings, 289-291, 330 psychological testing, 289, 292, 293 seizure incidence, post-operative -, 289, 305 sensory function, post-operative findings, 299303, 334, 335

vasomotor changes, 303, 304 Hepatic coma, and fatty acids, short-chain -, 280-282 Hepatic encephalopathy, and ammonia, toxicity, 269, 278-280 classification, 277 and etiology, 277, 278 definition, 276, 277 hose’s type, symptoms, 277, 278 pathogenesis, 278-283 and Schistosomiasis japonica, 278 Hepatocerebral disease, definition, 269 studies, 269-283 Hepatolcnt icular degeneration, and ceruloplasmin, 271, 272 classification, and genetical analysis, 276 clinical features, 269, 270, 274 and copper metabolism, 269, 271-274 genetical analysis, and clinical types, 274-276 and liver, histochemical changes, 273, 274 stages, and histochemical changes, 274, 275 Hippocampus, after-discharge, and amygdaloid nuclei, 42, 43, 48, 51 basic phenomena, 42, 43 and psychotropic drugs, 40-53 and reticular formation, 43, 48, 49 rhythmic activity, and sleep, stages, 209-215 Hyperkinesia, and Hallervorden-Spatz disease, symptoms, 373

and stereotaxic surgery, 339-349 dypothalamic-hypophyseal activity, and EEG, after-reaction, 90-1 11 and slcep, paradoxical -, 90-1 1 I Hypothalamotomy, posteromedial -, considerations, 358-370 post-operative changes, 363-370

S U B J E C T INDEX

technique, 358-363 Hypothalamus, activating system, and CNS depressants, 134 and EEG, arousal reaction, 138-141 ergotropic triangle, stimulation, 359-363 and waking center, 364 ergotropic zone, and emotion, 350 posterior nucleus, and stimulation, experiments, 358-363 stimulation threshold, and chlorpromazine, 140 trophotropic zone, and emotion, 350 Imipramine, and hippocampus, after-discharge, 46, 42 Lysergic acid diethylamide, and hippocampus, after-discharge, 46, 52 Mental retardation, and bovine brain hydrate, 1-39 anthropometry, 13, 21, 22, 29-31 behavioral and phsyical changes, 9, 10 diagnostic categories, 32-36 EEG, changes, 12-20 ossification, effect, 3, 12 periodical tests, 3, 8-1 2, 14-24 survey of subjects, 2-7 Meprobamate, and behavior, attention reaction, 131 stimulation threshold, 133 and EEG, pattern, 131 and hippocampus, after-discharge, 46, 52 Methamphetamine, and behavior, aberrations, 194-201 adaptive mechanism, 196-201 changes and neurochemical correlates, 192, 193, 201-203 experiments 194-201 responsive activity, 196-201 blood level, 192-206 chronic adminstration, and limbic structures, 222 excretion, 192 intoxication, and behavior, 192-206,221 changes and neurochemical correlates, 201-203 and brain constituents, 202, 203 and chlorpromazine, 195, 196, 201 clinical features, 193, 194 experiments, 192-201 and motor acticity, 195-197 studies, 192-206

435

tissue distribution, 192 long-term administration, and behavior changes, 194-201 psychosis, behavioral symptoms, 193, 194 clinical features, 192, 193 withdrawal syndrome, 193 and sleep, cat, EEG pattern, 221, 222 Motor cortex, electrical stimulation, sleep and wakefulness, 54-63 responsiveness, and arousal, 55, 56 stimulation, and peripheral muscular response, 60 and pyramidal tract, response, 58-61 and rhythmic after-discharges, 57 Motor system, and drug effects, analysis, 113-147 Multiple sclerosis, clinical features, 187, 189 clinical types, classification, 188, 189 diagnostic criteria, 186 diagnostic signs, 188, 189 epidemiological and clinical aspects, 183-190 etiology, hypotheses, 183-190 and optic nerve, atrophy, 188-190 prevalence rates, 187, 188, 190 and geomagnetic latitude, 190 Muscle relaxants, electromyography, and decerebrate rigidity, 144-146 mode of action, and ataxia, 142-147 site of action, and muscle spindle discharge, 143, 144 Muscles, peripheral -, responsiveness, and motor cortex stimulation, 60, 61 spinal reflex activity, and sleep, 61 Myelination, and triangular tract, Helweg, fibers, 160-168 Narcolepsy, and sleep, stages, 226 Neocortex, and sleep, stages, automatic frequency analyzer, 209 Nictitating membrane, activity, and EEG, acute cat, 117-1 19, 122 and peripheral nerves, stimulation, 122 Olivo-cerebellum, atrophy, and triangular tract, Helweg, 168-1 78 Optic nerve, atrophy, and multiple sclerosis, 188-190 Ort h o-sleep,

436

SUBJECT INDEX

definition, 230 and EEG, characteristics, 264 and motoneuron, excitability tests, 242, 243 and para-slecp, transition, 233-235, 238, 239, 248,249 rellex response, changes, 233 reflexes, and picrotoxin, 244-246 and strychnine, 244-246 stimulus intensity, and nerve threshold, 236, 237 Para-sleep, autonomic activities, 246-253 definition, 230 induction, artificial -, 253-264 and w-butyrate, depressive action, 257-265 and fatty acids, 253-265 and motoneuron, antidromic focal potential, 241, 242 excitability changes, 237-241, 243 excitability tests, 242, 243 and ortho-sleep, transition, 233- 235, 238, 239, 248, 249 rcflcx, monosynaptic -, and picrotoxin, 243-246 and strychnine, 243-246 reflex activity, 230-237 effect of transection, 231, 232 reflex response, and nerve stimulation, intensity, 231, 233 somatic activities, 230-246 stimulus intensity, and motor unit activity, 239 and nerve threshold, 235-237, 240, 241 Parkinson disease, EEC, recordings, 342, 343 evoked potentials, recordings. 342-346 hypcrkincsia, and ventrolatcral thalamotomy, 339-349 Phenobarbital-Na, and behavior, attention reaction, 134 stimulation threshold, I33 and EEC, arousal reaction, 131, 134 Physost igmine, and hippocampus, after-discharge. 47, $2 Prosencephalon, crgotropic and trophotropic circuit, and emotion, 350, 351 Psychotropic drugs, and hippocampus, after-discharge, 40-53 and sleep, cat, cycle pattern, 220,221 human -, cylcc pattern, 220 narcoleptic syndrome, 226 Reserpine,

and behavior, attention reaction, 131 and EEG, arousal reaction, 131 and hippocampus, after-discharge, 46, 49, 52 Reticular formation, activating system, and chlorpromazine, 134 and CNS depressants, I34 and EEG, arousal reaction, 138-141 and fatty acids, 281 and sleep, evoked potentials, 219 and spccics specificity, 138-141 and hippocampus, after-discharge, 43, 48, 4') mesencephalon, and limbic system, 353,355 and nictitating membrane, activity, 119, 122 and sleep, paradoxical -, 107, 108 Reticular system, brain stem, and nervous activity, 353 Reticulotomy, upper mesencephalic -, technique, 355 Schizophrenia, biological approach, 192-206 Scopolamine, and hippocampus, after-discharge, 47, 49, 52 Serotonin levels, brain and behavior changes, 203-206 Sleep, activated -, neural mechanisms, 123-125 and peripheral phenomena, 124 cat, cycle, pattern and arousal stimulation, 220 and convulsant drugs, 223-225 and psychotropic drugs, 220, 221 EEG pattern, and methamphetamine, 221, 222 polyphasic pattern, 213, 220 and seizure discharge, induced focal -, 222224 children, cycle pattern, 214, 215 EEG pattern, 215 cycle, definition, 219 cycle and phase patterns, different species, 2 19-222 evoked potentials, and ascending reticular activating system, 219 and auditory stimulation, 218, 219 changes, 215-219 and input controlling mechanisms, 219 and rapid eye movement, 218 and sensory stimulation, 218, 219 human -, cycle pattern, and psychotropic drugs, 220 cycle and phase pattern, and petit mal, 225 drowsy pattern, 210

SUBJECT INDEX

437

EEG pattern. and arousal stimulation, 220 procedures, 350-371 monophasic pattern, 213, 220 Stereotaxic surgery, human nocturnal --, and anatomical data, 339 depth, determination, 213 basic questions, 339 and seizure discharge, 224 and extrapyramidal disorders, 339 and focal epilepsy, 225 Striate arteries, galvanic skin response (GSR), 213 retrograde ramification, polygraphic study, 213, 226 and cerebrovascular disease, 74-77 and seizure discharge, 222, 224, 225 Strychnine, focal -, distribution, 225 and sleep, cat, stages, 213 cycle pattern, 223-225 mechanism, and methamphetamine, 222 Thalamotomy, ventrolateral, monkey, effects, analysis, 339-349 cycle and phase patterns, 212, 213 and extrapyramidal disorders, stages, 210-213 mechanism, 347 and motor cortical responsiveness, 54-63 and hyperkinesia, 339-349 narcoleptic syndrome, Thalamus, and psychotropic drugs, 226 nucleus, division, neural mechanism, 208-228 and architectonic structure, 347 nocturnal-, VL-nucleus, children, rhythmic waves, 215, 216 physiological identification, 347, 348 paradoxical phase, radiological standard, measuring, 340, 341 and brain, electrical stimulation, 253 Thiopental sodium, neural mechanisms, 90-109 and hippocampus, after-discharge, 43, 46 and picrotoxin, 244 Triangular tract, Helweg, and strychnine, 244 comparative anatomy, 153 studies, 230-265 direction, 150, 151 terminology, 230 and fibers, paradoxical -, constituents, 152 and cerebral structures, 10s-108 diffuse formation, I 54-1 56, 158-160, 179 and EEG, after-reaction, 91-94 myelination, 160-168 changes, sequence, 94 properties, 158, 159 substages, 93, 94 termination, 156-1 58 and hypothalamic-hypophyseal activity, functional significance, 152, 153 90-1 11 lower limit, 152, 157 and reticular formation, 107, 108 and olivary nucleus, 151, 152, 159, 160 and peripheral muscular response, 60, 61 atrophy, 168-178 phase, definition, 219 origin, considerations, 178-1 80 and pyramidal tract response, 58-61 and pyramidal tract, schizophrenia, topographical relation, 157, 158 cycle and phase pattern, 226 studies, 150-1 80 and seizure discharge, 222-225 upper limit, 151, 152 stages, Trophotropic circuit, and brain, phylogenetic development, 2 10-2I 5 prosencephalon, and brain structures, electric activity, 208and emotion, disorders, 350, 351 215 Trophotropic zone, and narcoleptic syndrome, 226 hypothalamus, neocortical activity, automatic frequency and emotion. 350 analyzer, 209 and peripheral somatic activities, 209 Ventrolateral nucleus, state of -, stimulation, behavioral and electrographic viewpoints, rhythmic potentials, 340 55-59 Spheroid structures, Wakefulness, Hallervorden-Spatz disease, axonal degeneraand motor cortical responsiveness, 54-63 tion, 373, 405, 416 and pyramidal tract response, 58, 59 histochemical components, 399-405 Waking center, Stereoencephalotomy, sedative --, and hypothalamus, ergotropic triangle, 364

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