C J Long
ANATOMY OF EMOTION
Overview of Topics
- Trace the pathways for limbic system interconnections that are responsible for emotionality.
- What role does the hypothalamus play in emotion?
- 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?
- 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.
Anatomy of Emotion
- 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)
- 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
- 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
- Lesion--emotional hypersensitivity (disappears with handling)
- Impaired passive avoidance (not appetitive)
- Increased exploration (errors) and exaggerated startle response
- Olfactory projection fields (pyriform)
- Cingulate gyrus
- Clinical--lesion for anxiety
- Transient increase in emotionality but less response to stress.
- 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.
- Mammillary Bodies (Posterior hypothalamus)
- Anterior Thalamic Nuclei - DTPS
- Cingulate Gyrus (Neocortex)
- Presbicium -- connects with Hippocampus
Terms to Know
||Temporal lobe syndrome
Links to Associated Areas