Chapter 3C: Neurobiology of Reward

Question 1

Who was Thorndike?

Answer 1

Developed the law of effect

Rewarded behaviour is learned
Punished behaviour is eliminated

Question 2

Who was Skinner?

Answer 2

Reinforcement: behaviour is controlled by its consequences

Operant conditioning
“Skinner box”

Question 3

What are the steps involved in operant conditioning?

Answer 3

1. Situation: the learning environment
2. Response: the behaviour emitted
3. Consequence: stimulus, reinforcement and punishment, positive or negative
4. Result: perform behaviour (reinforcement) or do not perform behaviour (punishment)

Question 4

What are the differences between classical and operant conditioning?

Answer 4

Classical: stimulus precedes response and elicits it, elicited responses, learning as a result of association, Pavlov

Operant: stimulus (result) follows response and strengthens it, emitted responses, learning as a result of consequences, Skinner

Question 5

What does motivational stated or drive have to do with learning?

Answer 5

An internal condition (changing with time), that orients an individual to a specific set of goals

e.g. hunger, thirst, curiosity, mating

Hypothalamus: homeostatic regulation

Question 6

What are incentives?

Answer 6

Goals or reinforcers in the external environment

e.g. food, water, good grades, a mate

Brain mechanisms?

Question 7

What did Olds and Milner find out about brain stimulation-induced reward?

Answer 7

Stimulation of lateral hypothalamic sites (medial forebrain bundle) induced a preference for the spot for which it was received: conditioned place preference

When the rat had the opportunity to deliver its own stimulation it would do so at a high rate (self-stimulation)

Reward/reinforcement centre?
Pleasure centre?

Question 8

What is the mesocorticolimbic dopamine?

Answer 8

Ascending pathway from Ventral Tegmental Area (VTA) to forebrain structures

Nucleus Accumbens (NAcc) & Striatum
Limit structures (hippocampus, amygdala)
Prefrontal cortex

Self stimulation either directly or indirectly activated dopamine release in the NAcc

Question 9

What is the relationship between reward and addiction?

Answer 9

Self stimulation “seems” similar to addictive behaviours, promoted by substances of abuse

Can addition be explained by changes in the reward system?
self administration paradigms

Question 10

What are the cognitive elements of craving?

Answer 10

The way everything gets associated

Stimuli associated with different outcomes

Wiring set up to take stimuli and create a desire for what’s associated with that

Addiction looks like every other kind of learning and memory