Lecture 20 Flashcards
Emotion (3 parts) & physiological changes
Limbic system
Feeling, behavior, & physiological states
Physiological changes: heart rates, blood flow, piloerection, sweating
Walter Connor:
- sympathetic prepares for metabolic use
- parasympathetic promotes metabolic build up
Categorical theory of emotion
Humans share basic emotions
Paul Ekman thought we had 6
Dimensional model of emotion
1) Arousal: low > medium > high
2) Valence: negative > neutral > positive
(1)↑
<—|—>(2)
↓
Component process theory of emotion
(see 20.4)
event →appraisal ↔️
↔️ motivation |
↕️ |
↔️ physiology | ↔️ feelings
↕️ |
↔️ expression |
differences in individuals from appraisal & reaction differences
Hypothalamus (Bard & Hess)
Integrates visceral & somatic motor components
Basic circuits in diencephalon & related brainstem
Phillip Bard:
- lesioned cats to create “sham rage”
- require intact caudal hypothalamus connected to brain stem
- subjective emotion = cortical; expression not necessarily
Walter Hess:
- stimulated discrete hypothalamus areas to elicit emotions (rage, fear)
Reticular formation
Input: forebrain & hypothalamus
Output: motor systems
Controls: sleep/wakefulness, cardiovascular functions, respiration, urination, vomit, sweating
Klüver-Bucy syndrome
MTL lesions
visual agnosia, unusual oral behavior, hyperactivity, hypersexuality, fearless, “tame”
can be amygdala removal alone
bilateral
(unilateral → deficits on lesioned visual field w/ severed cc)
Emotional expression: voluntary vs involuntary pathways
Voluntary:
- pyramidal & extra pyramidal
- projection from motor
-cortex & brainstem
- “pyramidal smile”
- forced smile
Involuntary:
-extrapyramidal
- projections from forebrain & hypothalamus
- “Duchenne smile”
- emotional smile
DISTINCT: facial pariesis of voluntary doesn’t stop involuntary
Papez circuit & modern addition
Papez circuit: 🔁
→ [cingulate cortex & hypothalamus] → [mammillary bodies] → [anterior thalamus] → [cingulate gyrus] →
[hippocampus] → [fornix] →
Modern additions: orbital & mPFC, vBG, md nucleus of thalamus, amygdala
Amygdala (function, fear response)
Attributing emotional significance to experience + associative learning
Conditioned fear response
AUDITORY
[auditory info ] → [mGC] → [AC]
SENSORY ↓ ↓
[sen. porjections] → [amygdala]
Fear learning: MGN → basal lateral amygdala
Fear responses: central amygdala → reticular formation
NMDA receptor antagonists in amygdala
Block conditioned fear acquisitions
Glutaminergic synapses LTP
What likely accounts for ‘feelings’
Neocortex, amygdala, & subcortical interactions
Emotion laterilization
R Hemi: prosody of speech, processing negative emotions
L Hemi: faster processing, processing positive emotions
Depression & PTSD
Depression: 10-25% of women, 5-12% of men
La Hem lesions associated w/ inc.
PTSD: often omorbid w/ depression & substance use disorder
associated w/ reduced hippocampal volume (cause or consequence?)
