Emotions and the amygdala

Question 1

What does the limbic system include?

Answer 1

The thalamus, hypothalamus, hippocampus and amygdala

Question 2

What does Mcleans circuit include?

Answer 2

Amygdala (subcortical)
Orbital cortex (most directly involved with emotions)
Prefrnotal cortex (planning, strategies)
Dorsolateral nucleus of thalamus (subcortical)
Basal ganglia (ventral structure)

Question 3

Via which structure does the limbic system influence emotional behaviour?

Answer 3

Hypothalamus

Question 4

How do the structures of the limbic system influence aspect of emotion? 
Thalamus (mediodorsal nuclei)
Hippocampus 
Amygdala 
Hypothalamus (mammillary body)

Answer 4

Thalamus (medio-dorsal nuclei) - declerative memory (facts)
Hippocampus - memory acquisition (volatile to non-volatile)
Amygdala - fear conditioning
Hypothalamus (mammilary body) - declarative memory

Question 5

Which part of the limbic system is most involved in emotion

Answer 5

Amygdala

Question 6

Location of amygdala

Answer 6

Anterior-medial part of temporal lobe, rostral to hippocampus

Question 7

What does the amygdala do?

Answer 7

Connects areas responsible for
somatic expression -
Conscious feeling -

Question 8

What is the role of amygdala within limbic system?

Answer 8

Connect areas responsible for:
Somatic expression - hypothalamus & brainstem
Conscious feeling - fear - parahippocampal gyrus, cingulate cortex, prefrontal cortex

Question 9

Which areas are responsible for somatic expression of emotion

Answer 9

Hypothalamus and brainstem

Question 10

areas responsible for conscious feeling such as fear

Answer 10

Para hippocampal gyrus
Prefrontal cortex
Cingulate cortex

Question 11

What does electrical stimulation of amygdala lead to?

Answer 11

Fear and apprehension

Question 12

The amygdala consists of 3 heterogeneous nucleus, what are the main functional subdivisions?

Answer 12

medial
Basolateral
Central

Question 13

Role of basolateral amygdala

Answer 13

Conditioned fear
Router to/from basal ganglia, motor system, cortex, sensory nuclei of thalamus
Output to central nucleus of amygdala
Connections: it is connected to hippocampus

Question 14

What is the basolateral region made of

Answer 14

basolateral
basomdial
lateral

Question 15

Role of central nucleus of amygdala

Answer 15

General fear
Input: receives input from the thalamus and cortex which provide it with info about the sensory stimuli animal is expreincing
Output: projections to ears which control fear such as paraventricular area of hypothalamus (cortisol), lateral hypothalamus (autonomic nervous system) and pariaqueductal gray (freezing due to fear)
Connections: hypothalamus
Result sin physiological response - increased HR, etc

Question 16

What does the central nucleus of amygdala stimulate?

Answer 16

paraventricular area of hypothalamus (cortisol) 
Lateral hypothalamus (autonomic nervous system) pariaqueductal gray (freezing due to fear)

Question 17

What physioclogical responses does central nucleus of amygdala lead to?

Answer 17

Cortisol releasee, sweating, increased heart rate, freezing due to fear, startles response

Question 18

How does basolateral nucleus acquire conditioned fear?

Answer 18

It has a memory enhancing effect
important for remembering emotionally arorunsing events
Makes memories more vivid
Lesions in BLA = drastic reduction to conditioned fear response but shocked STILL REMAINS

Question 19

What is Kluver-Bucy syndrome?

Answer 19

Bilateral ablation of inferior temporal lobe (includes hippocampus and amygdala) –> fearless, emotionless, mellow –> hyper sexuality, hype-orality, failure to recognise familiar faces, compulsive reactions/observation

Question 20

Amygdaloid lesions manifest in humans

Answer 20

Rare
caused by calcium disposition in the amygdala
bilateral degenerations can lead to failures to recognise familiar faces, or failure to identify fear, anger, surprise

Question 21

how do Affective mood disorders affect the amygdala?

Answer 21

AFFECTIVE MOOD DISORDERS = abnormal regulation of emotions
increased levels of activity int he amygdala, orbital and medial prefrontal cortex in patients with depression
Scans shows increased blood flow in amygdala, orbital, and medial prefrontal cortex