2 addiction

Question 1

how to diagnose addiction

Answer 1

11-point scale given in diagnostic and statistical manual of mental illness

Question 2

why is ADHD a risk factor for drug addiction

Answer 2

• treatments have high abuse liability, e.g. amphetamine
• so people might self-administer these to correct underlying defects in temperament e.g. to improve attentional focus

Question 3

brain reward systems overlap strongly with

Answer 3

dopamine pathways from the VTA

Question 4

which structure is thought to be involved in addiction? how do we know?

Answer 4

• nucleus accumbens
• all drugs of abuse increase DA release into the nac

Question 5

what do DA neurons do in addiction

Answer 5

• active when you first present the reward but then habituate
• then fire whenever you expect the reward, and decreases when you don’t get it

Question 6

what is the mesolithic DA system

Answer 6

VTA > NAc

Question 7

explain the incentive salience desensitisation therapy

Answer 7

• with repeated administration of a drug, DA release in the mesolimbic pathway increases
• so you want it more

Question 8

does dopamine have a role in hedonic actions?

Answer 8

• no because when you deplete dopamine you still have orally elicited liking and disgust reactions
• therefore dopamine makes you want, but doesn’t affect the drug’s effect on you

Question 9

problems with incentive salience sensitisation theory

Answer 9

1 in humans mesolimbic pathway activity actually decreases
2 it says that all individuals will become addicted - this is not true

Question 10

explain the opponent process theory

Answer 10

• at first you take a drug to get the positive effects
• but over time you develop tolerance
• and then you take a drug to get rid of the negative effects

Question 11

what underlies the positive state of the opponent process theory

Answer 11

dopamine, opioid peptides

Question 12

what underlies the negative state of opponent process theory

Answer 12

• dynorphin
• CRF
• NA

Question 13

what is the maladaptive conditioning theory

Answer 13

• at first you take a drug because of internal stimuli
• later you take it because of external stimuli
• supported as later on you start to engage more dorsal areas of the striatum in addition to the ventral areas > so stimulus response habits dominate drug seeking behaviour

Question 14

pfc activity in drug addicts? why?

Answer 14

• metabolism is significantly reduced in abstinent cocaine users
• maybe because less D2 in caudate/putamen > less excitatory input (because they inhibit indirect pathway) from hypothalamus

Question 15

what predicts familial risk of addiction? rat studies?

Answer 15

• reduced connectivity from pfc to caudate
• less D2 in NAc in humans addicted to drugs