Amygdala

Question 1

Emotions

Answer 1

Associated with ANS changes
Dimensions = arousal + valence

Biologically hardwired:
* Universal expressions across cultures (Ekman 1971)
* Infant emotions: same facial expressions between congenitally blind and sighted. Newborns exhibit basic expressions without learniing.
* Animals: mice show fear without learning

Question 2

Amygdala Subdivisions

Answer 2

Medial (olfaction)

Basolateral == cortical input
* Lateral amygdala = sensory input from both high/low routes (for neutral/conditioned + unconditioned fear stimuli)
* Raw sensory input from thalamus
* Processed sensory input from cortex

Central == hypothalamic output
* Central amygdala = output to fear response regions (hypothalamus, brainstem)

Question 3

Amygdala - General Info

Answer 3

Receives sensory input
* Raw (thalamus)
* Processed (cortex)

Links this info with effector systems
* Hypothalamus
* Brainstem

Many amygdala neurons respond to specific sensory stimuli

Facilitates associative learning:
* Links neutral or sensory stimuli to emotions or primary reinforcers

Question 4

Locationism

Answer 4

Emotions correspond to specific brain regions
Mapping is 1:1 - uniqueness (region only active for 1 emotion)
Consistently activated by emotion (for all individuals and contexts)

Question 5

Types of locationism

Answer 5

Anatomical - distinct regions for distinct emotions
Homological - inherited neural networks (shared w/ other mammals) that involve subcortical circuits

Question 6

Fear response: fast/slow routes

Answer 6

Fast: stimulus –> thalamus –> amygdala
Slow:
* stimulus –> thalamus –> cortex –> amygdala
* stimulus –> thalamus –> cortex –> hippocampus –> amygdala

Fear conditioning = a neutral stimulus becomes associated with an aversive event

Question 7

Locationism critiques

Answer 7

Amygdala = more involved in disgust than fear
Some bilateral amygdala patients CAN recognize fearful faces + have acoustic startle responses

CO2 inhalation (35% challenge) DID induce fear response in SM (replicated with 2 patients)

Question 8

Patient SM

Answer 8

• Urbach-Wiete (bilateral amygdala damage)
• Spared hippocampus + neocortex
• Intact cognitive function (IQ, memory, language, perception)
• Intact other emotions
• ## Able to recognize faces + non-fear emotions
• Impaired fear response, fear (face) recognition (snakes, spiders, scary movies, questionnaire/self-report of past, daily life experience sampling)

Question 9

Theory of constructed emotion

Answer 9

Emotions are not innate - they are constructed across networks (combine/constrain each other like ingredients in a recipe)
* Based on valence + arousal
* Made meanigful through cognition (network combos)