Physiology of Emotion

1
Physiology of Emotion

• Emotional response patterns
• Emotional communication
• Emotional experience

2
Emotional response patterns

• Observable behaviors
• Facial expression
• Stance or posture
• Voice characteristics
• Movement patterns
• Autonomic responses
• Fight or flight patterns
• Hormone secretion

3
Neural systems of emotional response patterns

• The amygdala
• Medial nucleus Sensory input, especially odor,
  relayed to forebrain and hypothalamus
• Central nucleus Sensory input via cortex and
  thalamus, relayed to hypothalamus and brainstem
  nuclei
• Basal nucleus Sensory input relayed to rest of
  amygdala and to PAG

4
The central nucleus

• Plays the major role in emotional response
  patterns
• Affects hypothalamus and both branches of ANS
  Increased HR and BP ulcers, urination, and
  defecation
• Affects brainstem nuclei to increase arousal
  (VTA), vigilance (LC), cortex activation (DLTN
  and nucleus basalis) and startle (pons)

5
More central nucleus effects

• Freezing response (PAG)
• Facial expression (trigeminal and facial nerve
  nuclei)
• Adrenal secretions (paraventricular nucleus)
• Destruction of central nucleus limits emotional
  response patterns.
• Electrical stimulation of central nucleus
  triggers fear, agitation, stress illness

6
Emotional response patterns in research

• Conditioned emotional response
• Augmented startle response
• Central nucleus damage limits both
• Humans show both patterns, with analogous results
  from damage
• Right amygdala activity is associated with
  enhanced memory of emotionally arousing material

7
The orbital frontal cortex Emotional inhibition
of action

• Multiple and broad inputs and outputs
• Damage (by accident or surgery)
• To treat tumors
• To relieve emotional distress
• Blocks practical, but not theoretical, judgment
  and planning
• GSR measures of emotional arousal to anticipated
  bad outcomes (Bechara et al, 1997, 1999)

8
The cingulate gyrus Emotional excitation of
action

• Electrical stimulation triggers emotional
  feelings
• Destruction produces akinetic mutism
• Is activated by provoking stimuli
• Anterior cingulate cortex is more active in
  extraverts
• Prefrontal cortex is more active in introverts

9
Emotional communication The right frontal cortex