Emotion

Question 1

In what two ways are emotions expressed?

Answer 1

• visceral motor responses

- stereotyped somatic motor responses

Question 2

What are the higher order neural centers that coordinate emotional responses?

Answer 2

• limbic system
• includes amygdala and several cortical frontal lobe areas
• concerted action of diverse brain regions constitutes an emotional “motor” system

Question 3

Forebrain areas that process emotional signals also mediate?

Answer 3

• goal-directed behaviours
• interpretation and expression of social behaviour
• rational decision making
• moral judgement

Question 4

When are forebrain areas that process emotional signals subject to maladaptation?

Answer 4

• when exposed to drugs of abuse

- when genetics or experiences promote psychiatric illness

Question 5

What did Duchenne identify about emotion and muscles?

Answer 5

• he found some muscles that are not easily controlled voluntarily
• indicates there are two pathways

Question 6

What are the two types of facial paresis?

Answer 6

• voluntary facial paresis (pyramidal)

- emotional facial paresis (extra pyramidal)

Question 7

What are the two pathways for facial movement?

Answer 7

• volitional movement (descending pyramidal and extrapyramidal projections from motor cortex and brainstem)
• neural systems for emotional expression (descending extrapyramidal projections from medial forebrain and hypothalamus)

Question 8

What are the functions of the lateral and medial parts of volitional movement?

Answer 8

• lateral: fine control of distal extremities

- medial: posture, proximal extremities

Question 9

What are the functions of the lateral and medial parts of emotional expression?

Answer 9

• lateral: specific emotional behaviours

- medial: gain setting, rhythmical reflexes

Question 10

Where do the lateral and medial parts of both volitional movement and emotional expression synapse?

Answer 10

• lateral: motor neuron pools

- medial: motor neuron pools and brainstem reticular formation

Question 11

What motor neuron pools do the lateral volitional movement and emotional expression innervate?

Answer 11

• motor neurons of cranial nerve nuclei and ventral horn

- autonomic preganglionic neurons

Question 12

The motor neuron pools activated by volitional movement and emotional expression result in what actions?

Answer 12

• muscle contraction and movement

- activation of smooth muscle and glands

Question 13

What parts of the brain are considered to be Broca’s limbic lobe? What is the function?

Answer 13

• cingulate gyrus
• parahippocampal
• olfactory bulbs and cortex included at this time
• originally thought to be olfactory, now ascribed to processing emotion

Question 14

What parts of the brain are now considered to be limbic?

Answer 14

• orbital and medial prefrontal cortex
• cingulate gyrus
• parahippocampal gyrus
• amygdala

Question 15

What areas of the brain are no longer considered to be essential components for processing emotion?

Answer 15

• mammillothalamic tract
• anterior nucleus of the thalamus
• mammillary body
• hippocampus
• not needed to ascribe emotional meaning to stimuli

Question 16

What areas of the brain are considered to be essential components for processing emotion??

Answer 16

• ventral basal ganglia
• hypothalamus
• amygdala
• mediodorsal nucleus of the thalamus

Question 17

How do the amygdala, mediodorsal nucleus of the thalamus, ventral basal ganglia, and orbital and medial prefrontal cortex interact?

Answer 17

ventral basal ganglia –> mediodorsal nucleus orbital and medial prefrontal cortex amygdala –> ventral basal ganglia AND mediodorsal nucleus

Question 18

What are the three groups that make up the amygdala?

Answer 18

• medial group
• central group
• basal-lateral group

Question 19

What inputs does the media group of the amygdala receive?

Answer 19

• olfactory bulb and pyriform cortex

Question 20

What inputs does the central group of the amygdala receive?

Answer 20

• hypothalamus and brainstem

Question 21

What inputs does the basal-lateral group of the amygdala receive?

Answer 21

• orbital and medial prefrontal cortex

- associational cortex of temporal lobe

Question 22

What part of the amygdala is the output to the medial dorsal nucleus, ventral basal ganglia and orbital and medial prefrontal cortex?

Answer 22

• basolateral nulclei

Question 23

In general terms, what does the amygdala link?

Answer 23

• cortical regions that process sensory information with hypothalmic and brainstem effector systems

Question 24

How is the basolateral amygdala modulated?

Answer 24

• by indirect feedback coming from the ventral basal ganglia via mediodorsal nucleus of the thalamus and orbital and medial prefrontal cortex

Question 25

In general, what kind of sensory input does the basolateral amygdala receive?

Answer 25

- highly processed sensory input

Question 26

What type of stimuli do many of the neurons in the amygdala respond to?

Answer 26

- visual, auditory, somatic sensory, visceral sensory, gustatory and olfactory

Question 27

What type of stimuli are often required to evoke a neuronal response?

Answer 27

- highly complex stimuli | - neurons that respond to faces or objects in specific contexts

Question 28

Prefrontal and temporal cortical connections provide input from the circuits that integrate what?

Answer 28

- the emotional significance of sensory stimuli

Question 29

What actions does output from the amygdala to the hypothalamus and brainstem allow?

Answer 29

- influence activity in both somatic and visceral motor efferent systems

Question 30

What happens if the amygdala is removed?

Answer 30

- removes aggressive and fearful behaviour

Question 31

What is the pathway for a conditioned fear response to an auditory stimulus?

Answer 31

1. Auditory pathways 2. Medial geniculate nucleus 3. Auditory cortex to amygdala and just amygdala 4. Amygdala receives other projections as well 5. Output to circuits that govern somatic and visceral motor activity

Question 32

Which part of the pathway for a conditioned fear response is essential?

Answer 32

- need medial geniculate nucleus to amygdala | - don't need medial geniculate nucleus to auditory cortex to amygdala

Question 33

During the conditioned fear response what part of the brain causing the freezing reaction? The increase in blood pressure?

Answer 33

- freezing: amygdala to midbrain | - increase blood pressure: amygdala to hypothalamus

Question 34

What kinds of neurons are present in the caudate and putamen?

Answer 34

- medium spiny neurons

Question 35

What types of inputs does the amygdala receive for associative learning?

Answer 35

- primary reinforcers (positive/appetitive or aversive/negative) - neutral sensory stimuli

Question 36

The __ is the site where association between ____ stimuli and aversive or appetitive stimuli change the response to the ___ stimuli.

Answer 36

- amygdala - neutral - neutral

Question 37

What type of plasticity is associative learning in the amygdala? What is the evidence for this?

Answer 37

- probably Hebbian - NMDA-receptor dependent LTP is abundant in amygdala - NMDA-R block prevents fear conditioning

Question 38

What are the outputs of the associative learning in the amygdala?

Answer 38

- orbital and medial prefrontal cortex: implicit motor actions, explicit conscious processing to obtain rewards, avoidd punishers and implement long-term plans - hypothalamus and brainstem: visceral motor effector systems to prepare body for action

Question 39

What two functions is the amygdala necessary for?

Answer 39

- needed for humans to experience fear | - needed for humans to recognize fear in others

Question 40

An increase in blood flow to limbic system structures is associated with what condition?

Answer 40

- clinical depression

Question 41

What are dorsal divisions of the basal ganglia instrumental in gating?

Answer 41

- the activation of thalamocortical circuits that initiate volitional movements

Question 42

What parts of the brain are included in the dorsal divisions of basal ganglia?

Answer 42

- dorsal caudate - putamen - globus pallidus

Question 43

What is controlled by the "disinhibitory" circuit of the dorsal divisions of the basal ganglia?

Answer 43

- "motivation" to initiate movements is controlled here | - selection of appropriate movements is determined here

Question 44

What is the "disinhibitory" circuit of the dorsal divisions of basal ganglia?

Answer 44

1. Cerebral cortex and substantia nigra pars compacta both transiently excite caudate/putamen 2. Caudate/putamen transiently inhibits globus pallidus 3. Globus pallidus inhibits VA/VL complex of thalamus 4. VA/VL complex of thalamus excites frontal cortex

Question 45

What kind of neurons are present in the ventral striatum?

Answer 45

- medium and spiny type neurons like caudate and putamen

Question 46

What does the other disinhibitory circuit mediated through a "basal" ganglion control?

Answer 46

- controls limbic system gating

Question 47

What is the pathway in the disinhibitory circuit that controls limbic system gating (limbic loop)?

Answer 47

1. amygdala, hippocampus, orbitfrontal, anterior cingulate, temporal cortex excites 2. Ventral striatum inhibits 3. ventral pallidum substantia nigra, pars reticulata inhibits 4. mediodorsal nucleus excites 5. beginning of loop

Question 48

What is the "basal" ganglia in the ventral striatum called?

Answer 48

- the nucleus accumbens

Question 49

Structures ___ to or the same as those in ____ movement system are the target of the striatal output.

Answer 49

- analogous | - volitional

Question 50

DA modulation in nucleus accumbens is due to projections from where?

Answer 50

- projections from the ventral tegmentum | - rather than the substantia nigra pars compacta

Question 51

What types of neurons and interneurons does the ventral tegmentum area have?

Answer 51

- DA neurons | - GABA interneurons

Question 52

What are the dopamine neurons of the VTA analogous to?

Answer 52

- substantia nigra pars compacta of the motor system

Question 53

What are the nucleus accumbens medium spiny neurons analogous to?

Answer 53

- neurons of the caudate and putamen

Question 54

The amygdala _____ neural processes that invest ____ experience with ____ significance.

Answer 54

- mediates - sensory - emotional

Question 55

What does cocaine do?

Answer 55

- blocks dopamine reuptake transporters - excess in dopamine - neurons downregulate dopamine receptors (D2) - no longer able to run at basal level (no dopamine reward)