Neurophysiology of Emotion

Question 1

Neural system to produce: Learned fear

Answer 1

1. Sensory inputs travel to the lateral nucleus of the amygdala via two pathways - direct thalamo-amygdaloid pathway (rapid response) and indirect thalamo-cortico-amygdaloid pathway (later responses) –> integrates the inputs and forms linkage b/w fearful event and unrelated event (e.g. benign sound associated w/ electrical shock)
2. Paired information sent to the basal and intercalated nuclei for additional processing w/in amygdala
3. Info from lateral, basal, and intercalated nuclei sent to the central nucleus of the amygdala
4. Central nucleus decides what responses are required and relays info to appropriate parts of limbic system including hypothalamus
5. Hypothalamus plays role in generating physiologic responses to the fear (e.g. ANS response to increase HR and RR)

Question 2

Neural system to produce: Anger

Answer 2

• Mediated through amygdala via Dopamine @ D2 receptors

- Inhibiting anger via neocortex interacting w/ ventromedial hypothalamic nucleus and septal nuclei

Question 3

Neural system to produce: Avoidance

Answer 3

• Prevents occurrence of a behavior w/ short term rewards BUT long-term negative consequences
• Mediated through the lateral posterior hypothalamus, dorsal midbrain and the entorhinal cortex (heavily involved in olfaction)

Question 4

Neural system to produce: Sadness

Answer 4

• Mediated through the lower sector of the anterior cingulate cortex
• Strongly activated when recalling sad events/memories b/c we store components of events in the related part of the cortex where it was experienced originally

Question 5

Neural system to produce: Disgust

Answer 5

• Processing and recognition of social cues related to disgust
• Mediated through the insular cortex and putamen
• Damaged in Huntington’s Disease in which the pt loses ability to experience or recognize disgust (symptoms precede motor symptoms)

Question 6

Neural system to produce: Surprise

Answer 6

-Mediated through the parahippocampal gyrus (important in detecting novelty or unexpected events)

Question 7

Role of ventral anterior cingulate gyrus in control of emotion

Answer 7

• Integration of visceral, attentional and emotional input (intellectual recognition that we are experiencing a certain emotion)
• Regulation of affect, especially top-down control (controlling display of our emotions)
• Monitors or detects conflict b/w our “functional” state (right now) and new info that has potential or motivational consequences (I’m angry but I am standing in front of my boss) and relays that information to the prefrontal cortex

Question 8

Role of prefrontal cortex in control of emotion

Answer 8

• Reward processing (orbitofrontal) w/ amygdala to link new stimulus to a primary reward
• Integration of bodily signals (ventromedial prefrontal) to form a “gut feeling” –> decision when logical analysis is unable to help (responding to cues that didn’t consciously process but caught @ an emotional lvl)
• Top down regulation, especially towards delayed gratification (telling everyone at your job how much you hate them after waiting to get fired)

Question 9

Dorsolateral prefrontal cortex receives inputs from

Answer 9

• Motor areas (e.g. basal ganglia, pre- and supplementary motor cortex)
• Cingulate cortex, especially structures related to performance monitoring
• Several cortical association areas

Question 10

Ventromedial prefrontal cortex receives inputs from

Answer 10

• Amygdala
• Hippocampus
• Temporal visual association area
• Dorsolateral prefrontal cortex (other divison)