Dopamine, Reward, and Learning

Question 1

Which brain area did Olds and Milner (1954) find that rats self-stimulate?

Answer 1

Lateral hypothalamus

Question 2

Which brain areas are pleasurable to stimulate in humans?

Answer 2

Septal area

Lateral hypothalamus

Question 3

How do food, cocaine, sex affect NAc DA levels?

Answer 3

Increase

Question 4

What are the arguments against the theory of DA as the pleasure NT?

Answer 4

PD patients report normal subjective pleasure ratings
Animals with near-complete DA depletion have intact hedonic reactions to sweet stimuli
Stimulate DA release in animals - no effect on ‘liking’ reaction to sweet reward
In human addicts dissociation between amount of self-administered drug and reported pleasure rating

Question 5

What did Berridge and Kringelbach (2008) suggest DA encodes?

Answer 5

Wanting - not liking

Question 6

What are the 2 neurally-dissociable components of reward, according to Berridge and Kringelbach (2008) ?

Answer 6

Liking

Wanting

Question 7

What is Berridge and Kringelbach’s (2008) idea of ‘liking’?

Answer 7

In humans subjective feeling of pleasure

In animals hedonic reactions

Question 8

What is Berridge and Kringelbach’s (2008) idea of ‘wanting’?

Answer 8

In humans desire to obtain something

In animals motivated behaviour

Question 9

Which brain area and NTs are involved in liking?

Answer 9

NAc shell

Opioids, endocannabinoids

Question 10

What brain area and NT are involved in wanting?

Answer 10

NAc

DA

Question 11

What is the effect of inhibiting the caudal NAc shell and which type of behaviour does it regulate?

Answer 11

Fear

Defensive

Question 12

What is the effect of inhibiting the rostral NAc shell and which type of behaviour does it regulate?

Answer 12

Eating

Appetitive

Question 13

Name the 3 factors affecting learning

Answer 13

Contiguity
Contingency
Prediction error

Question 14

What is contiguity?

Answer 14

Reward (US) must follow CS by < few seconds

Question 15

What is contingency?

Answer 15

Reward (US) must occur more frequently in presence of stimulus than absence

Question 16

What is prediction error?

Answer 16

Learning only occurs if difference between predicted and actual outcome - reward not entirely predictable

Question 17

At the start of training, presenting a reward (US) after a CS causes VTA DA neurons to increase their firing frequency when?

Answer 17

After reward (US)

Question 18

After training, presenting a reward (US) after a CS causes VTA DA neurons to increase their firing frequency when?

Answer 18

After CS - activity shift

Question 19

What is conditioned inhibition?

Answer 19

VTA DA neurons decrease firing frequency after CS when always predicts reward (US) absence

Question 20

According to the error prediction theory of DA, is DA a cause or consequence of learning?

Answer 20

Cause

Question 21

According to the incentive salience theory of DA, is DA a cause or consequence of learning?

Answer 21

Consequence

Question 22

What is the error prediction theory of DA?

Answer 22

DA signals that outcome to stimulus not as expected

Question 23

What is the incentive salience theory of DA?

Answer 23

DA assigns motivation (‘wanting’) to obtain reward-predicting stimulus