Neuropsychology of emotion

Physiological Psychology, 21. EMOTION

EMOTION This course outline is designed to provide you with a study guide. Use the lecture, book, and other resources to expand on its contents.

OUTLINE TOPICS Objectives

Anatomy

Connections

LINKS

TERMS

QUIZ

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Lesson Objectives 1. 2. 3. 4. 5. 6. 7. 8.

Trace the pathways for limbic system interconnections that are responsible for emotionality. What role does the hypothalamus play in emotion? Outline Papez circuit and discuss his understanding of its function. Explain the temporal lobe syndrome Explain the effects of amygdaloid lesions and discuss its function. Describe the function of the amygdala in the regulation of emotional behavior. Describe what happens with lesions in the cingulate gyrus or hippocampus. What fibers are severed with a prefrontal lobotomy, and what are the behavioral effects?

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Difficult to define emotion and motivation in scientifically acceptable manner. Criteria--skeletal or autonomic response. Theories--many don't distinguish between subjective experience and behavior.

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Physiological Psychology, 21. EMOTION

Anatomy of Emotion ●

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Hypothalamus -- Integration ❍ Rage follows Dorsomedial nucleus stimulation ❍ Partially integrated ❍ Anterior and lateral hypothalamus, preoptic, septum, posterior hypothalamus are distinct systems--mediate flight, fight, attack (no pleasure) Limbic System -- Controlling mechanisms (unchanged from brain of lower animals) MENU

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Amygdala ❍ Limbic system designed to frustrate experimental analysis ❍ Fibers and Passage ❍ Temporal lobe syndrome (Kluver&Bucy (37) ■ Compulsive oral response ■ Loss of fear, aggressiveness ■ Hypersexuality, increased activity ❍ Conflicting results with lesion ■ Tame or wild ■ Territory (environment) is important factor (can't detect and react as at home) ■ Retard avoidance conditioning Hippocampus ❍ Lesion--perseveration ■ Repetitive running, poor discrimination, and activity ■ Passive-avoidance deficit ■ Facilitate or impair active avoidance; depends on particular task ■ Isaacson (1961) greater resistance to extinction ■ Memory: Pribram--Penfield ■ Lesion control Septum ❍ Lesion--emotional hypersensitivity (disappears with handling) ❍ Impaired passive avoidance (not appetitive) ■ Increased exploration (errors) and exaggerated startle response MENU

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Olfactory projection fields (pyriform) Cingulate gyrus ❍ Clinical--lesion for anxiety ❍ Transient increase in emotionality but less response to stress.

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Physiological Psychology, 21. EMOTION

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Thalamus ❍ Clinical data - major area for emotion ❍ Decortication sham rage not influenced by thalamic presence (removed by posterior hypothalamus) ❍ Role difficult to assess because of many nuclei. Cortex -- Integration, direction ❍ Removal--sham rage (stimulus bound) to neutral stimuli ❍ Mediates stimuli and directs attack. ❍ Required for pleasure. ❍ Temporal Lobe ❍ Frontal Lobe ■ Projections from hypothalamus ■ Lesion--impair delayed response. ■ Lobotomy--remove anxiety (intellectual deficit) ■ More restricted--good results ■ Orbital gyri--for chronic depression Brain Stem ❍ Regulates individual responses that contribute to complete emotional reaction. ❍ Rage to stimulation of higher areas doesn't occur after brainstem lesion. ❍ Activation in emotion. ❍ Connections with posterior hypothalamus.

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Anatomical Connections ●

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Septum ❍ Stria Terminalis Amygdala

Papez Circuit ●

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Hippocampus ❍ Fornix Mammillary Bodies (Posterior hypothalamus) ❍ Mammalothalamic tract Anterior Thalamic Nuclei - DTPS Cingulate Gyrus (Neocortex)

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Physiological Psychology, 21. EMOTION

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Presbiculum -- connects with Hippocampus

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Terms to Know Amygdala

Temporal lobe syndrome

Lobotomy

Hippocampus

passive avoidance

Limbic system

Fornix

perseveration

orbital gyri

Septum

Cingulate Gyrus

Mammilary Bodies

Posterior hypothalamus

Presubiculum

Sham rage

Lesson Objectives - Theories of Emotion 1. Discuss problems with the study of theories of emotion. 2. Describe the similarities and differences between James-Lange, Cannon-Bard, & Shacter & Singer's theories of emotion. 3. Discuss Schacter & Singer's theory of emotion. 4. Explain how emotion is a crucial mechanism for survival. 5. Explain the relationship of emotion and attention. 6. Describe the differential effects of RF vs. PH lesions and discuss the implications regarding emotional behavior. 7. Explain what P.T. Young meant by three properties of stimuli. 8. Describe the role of the posterior hypothalamus in emotion. 9. Describe how Routtenberg's 2 arousal system and Kawamuar etal, 1961 research aided in our understanding of emotion. MENU

General Problems with Theories ● ● ●

The term emotion refers to behavior and feelings. Feelings are subjective and difficult to measure empirically. Components of same behavior taken as an indicant of emotion seen in non-emotional context.

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Physiological Psychology, 21. EMOTION

Early Theories of Emotion James-Lange Theory ●

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James proposed that bodily changes follow directly the perception of the exciting fact, and our feeling of the same changes as they occur is the emotion. Lange's modification indicated that vasomotor changes are the emotions Both viewed emotion as the perception of a response by the nervous system. Both suggest that the underlying processes perceived as emotions are autonomic.

Cannon-Bard Theory Objections to James-Lange ● Isolating the viscera does not impair emotion ● Viscera respond to many non-emotional states (digestion) ● Viscera are insensitive, slow to respond Sympathetic Nervous System (SNS) activity - regarded as preparatory for struggle ● Epinephrine cooperates with the SNS to: ❍ Free glycogen from liver for muscles. ❍ Aid in converting lactic acid to glucose by increasing respiration. ❍ Redistribute blood to needed areas. MENU

Cannon-Bard Thalamic Theory ● Viewed emotions as the result of concurrent brain stem & cortical events ● Cortex inhibits thalamus ● Emotion-producing stimuli remove inhibition ● Impulses released to ANS result in emotional behavior

Lindsley's Arousal Theory ● ● ● ● ●

Both visceral and somatic impulses converge on the reticular formation Impulses integrated and projected to the hypothalamus SNS activity Also operate through diffuse thalamic projection system on cortex Emotion falls on arousal continuum

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Physiological Psychology, 21. EMOTION

Schacter and Singer's Theory ●

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Emotional feelings and behavior are the products of information from 2 systems ❍ Internal state - hypothalamus and limbic system ❍ External environment (context in which the internal state occurs) Humans given adrenaline may report that they feel or behave as if they are more hostile or elated (depending upon the environment stimuli) Effects of adrenaline on 3 groups: informed, uninformed, misinformed ❍ Informed group did not change significantly in hostile or pleasant environment ❍ Other two groups did change.

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Conclusion: Complexity of emotionality is due to the fact that many different environmental stimuli may be influencing the behavior. TOP

Related Research Routtenberg (1968) 2-arousal systems: ● Reticular formation - cortical desynchronization; provides organization of cortex for response. ● Limbic system - provides control of response through incentive-related stimuli. Kawamura, Nakamura, & Tokizane (1961). ● Lesions between reticular formation and DTPS abolish cortical desynchronization but leave limbic system responsive. ● Lesions in posterior thalamus don't influence cortical desynchronization but abolish the limbic system's response to stimuli. ● The limbic system and cortical systems are separate systems that interconnect at brainstem level.

Emotion Vs Sensation P.T. Young states that stimuli have 3 properties: ● Sensory - cortex ● Activating - reticular formation ● Hedonic - limbic system (positive or negative reinforcing stimuli)

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Primary - certain stimuli (e.g., pain) produce avoidance behaviors which are negatively reinforcing. Other stimuli remove aversive stimuli and produce approach behavior (negative reinforcement). Many of the stimuli to which we respond have acquired positively or negatively reinforcing properties by virtue of the fact that they have been paired with primary reinforcing stimuli.

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Revised Theory of Emotion Emotion serves two functions: ● Bring autonomic nervous system into play (SNS) to prepare the organism to cope with a threatening object or situation. ❍ This SNS activity, beyond certain limits, is aversive; therefore, its presence "motivates" an organism to make a response to decrease it. ● Emotion is a crucial mechanism for survival: If prepared to cope with stimuli and respond, are more likely to survive and reproduce. ❍ An emotional response is an adaptive response to stimuli in the environment. ❍ Emotional responses only begin to be maladaptive when the environment becomes very complex (e.g. man). MENU

Emotion and Attention Stimuli reach all levels of the nervous system, including the cortex, regardless of the state of organism (from sleep to wakefulness). There are some stimuli which reach cortex and can't be interpreted. ● When incongruent, novel, or partial information is coded, the following result is produced: ❍ Cortex feeds back to reticular formation, increasing cortical desynchronization ❍ This information is transferred from the cortex - RF - to the posterior hypothalamus and activates the limbic system ❍ The limbic system activates the SNS & produces emotional behavior. ● Connection between the limbic system and the cortex is crucial for conditioning. MENU

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Physiological Psychology, 21. EMOTION

Emotional Behavior Emotional behavior refers to the response of the SNS and the overt behavioral response occurring because of these stimuli. Both the sympathetic nervous system (SNS) and overt behavioral responses generally occur in response to some stimulus (external or internal) ● External - any environmental stimulus ● Internal - stimulus resulting from changes within an organism (food deficit) ● Emotional behavior is a response to internal stimuli (SNS and limbic system activity) and external stimuli (Schacter and Singer). The complexity encountered in the study of emotional behavior is due solely to the infinite number of environmental stimuli which may be involved.

Emotional Disorders Neuroses result from the inability of the organism to suppress Sympathetic Nervous System (SNS) activity. Can be accomplished by: ● Drugs to reduce SNS, ascending reticular influence and behavioral arousal ● Conditioning (changing the perception of environmental stimuli) ● Removing subject from environment producing this behavior ● Psychoses - probably, in part, due to biochemical disturbance and conditioning. MENU

Terms to Know Epinephrine

SNS

James-Lange Theory P.T.Young Cannon-Bard Theory

Routten berg's 2 arousal system

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Lindsley's arousal theory Schacter and Singer Theory Posterior hypothalamus