Emotion 2

Question 1

what is a reward?

Answer 1

an object or event that elicits approach and is worked for. It is associated with wanting an liking. Wanting is characterised by feeling of desire and approach behaviour. Liking is characterised by deeling of pleasure and other objective responses e.g. facial expressions

Question 2

what is clinical relevance?

Answer 2

• Alterations in the brain substrates of reward-related processes are likely mechanisms underlying addiction.
• Our experience of pleasure and desire can also be altered in neuropsychiatric disorders, including depression.

Question 3

what is instrumental conditioning?

Answer 3

• operant conditioning
• e.g. making an animal work for food

Question 4

what is intracranial electrical self-stimulation

Answer 4

• if an animal can realise that a stimuli elicits a response then they will work to administer this stimuli

Question 5

what is intracranial drug self-administration?

Answer 5

if an animal realises that a drug results in a positive feeling then they will work to administer the drug

Question 6

what is Intracerebral microdialysis to measure neurotransmitters associated with rewarding stimuli?

Answer 6

• measures neurotransmitters from extracellular space
• can be analysed chemically
• depending on how much neurotransmitter it can be investigated on how animals may be feeling

Question 7

what is the Mesolimbic/mesocortical dopamine system?

Answer 7

• originates in the ventrotegmental area of the midbrain to the nucleus acumbuns
• release of dopamine in the NA is associated with reward

Question 8

Electrical stimulation of self-stimulation sites, Fiorino et al. (1993)

Answer 8

• study finds animals will work to release dopamine in the nucleus accumbus
• In the VTA increases accumbal dopamine levels measured by in vivo microdialysis

Question 9

Food increases accumbal dopamine, Radhakishun et al. (1988)

Answer 9

dopamine increases when an animal encounters a rewarding stimuli such as food

Question 10

Drug of abuse increase accumbal dopamine, Dichiara and Imperato (1988)

Answer 10

• when administering addictive drugs to animals, dopamine in the NA increases
• suggesting we chase for more as we seek this increase in dopamine as it results in feelings of pleasure

Question 11

how can we measure dopamine releasie in the nucleus accumbus in humans

Answer 11

you can indirectly measure dopamine released by measuring a tracer bind to dopamine

Question 12

meso-corticolimbic dopamine system

Answer 12

• rewards increase NAC dopamine
• systemic and intra-NAC dopamine antagonists block responses normally maintained by reward

Question 13

cholinergic projection from PPTg to VTA

Answer 13

• electrical self-stimulation
• Cholinergic drugs are self-administered into VTA

Question 14

Glutamate projections from mPFV to VTA

Answer 14

• electrical self-stimulation
• stimulate dopamine release in NAc

Question 15

Facial expressions associated with liking, Berridge and Robinson (2003)

Answer 15

• found animals and humans showed a dislike to aversive stimuli such as a bitter taste, and showed a liking response to a sweet taste

Question 16

effects of Morphine Pecina & Berridge (2000)

Answer 16

• looked at facial expressions and liking
• when administered dopamine the dopamine found an aversive reaction, but resulted in wanting
• when administered morphine, liking increased

Question 17

Effects of amphetamine Wyvell & Berridge (2000)

Answer 17

• amphetamine decreases liking
• amphetamine however does increase wanting as increases dopamine which drives us to seek the pleasurable experience

Question 18

what are some functional implications of the amygdala?

Answer 18

• A ‘common currency’ of emotion may enable brain to generate adaptive responses based on integrated assessment of positive and negative stimuli.
• Brain substrates, such as dopamine, nucleus accumbens, and amygdala, may not play specific role in emotion, but contribute to fundamental cognitive processes that are associated with both aversive and appetitive stimuli