dopamine

Question 1

reward pathway

Answer 1

behaviour causes release of dopamine in ventral tegmental area which leads to pleasure in nucleus accumbens. part of the mesolimbic pathway.

Question 2

why was reward pathway evolved? why can it be bad?

Answer 2

response for behaviours that are good for us e.g. eating. it can become maladaptive when responding to harmful behaviours.

Question 3

Jousta (2012)

Answer 3

dopamine levels increased in participants given gambling task whether they win or lose.

Question 4

why do addicts experience tolerance
how does it effect withdrawal

Answer 4

overtime dopamine receptors become less sensitive. research shows a decrease in D2 receptors and increase in dopamine release. they engage more to for same sensations. engaging to avoid negative withdrawal due to lack of dopamine

Question 5

how is the frontal cortex involved in maintenance

Answer 5

FC linked to decision making and memory. behaviour can change the brain circuits controlling what is paid attention to - brain attaches to much importance to behaviour (salience) and cues. Dopamine makes them want to engage (to get rid of urges) not just like it. most addicts report that they no longer enjoy the sensations but can’t overcome cravings.

Question 6

volkow

Answer 6

cocaine addicts have abnormalities in fc and impaired decision making

Question 7

wang

Answer 7

addicts show increases activity in the fc when exposed to the addictive behaviour and associated cues.

Question 8

Varenicline

Answer 8

reduces dopamine release by binding to nicotine receptors. brain thinks its had nicotine and small amount of dopamine released. nicotine cant access receptors so cigarettes not pleasurable. alleviates craving and withdrawal

Question 9

dopamine and multitasking

Answer 9

Levitin found that multitasking causes feedback loop similar to addiction. activates fc and reward pathway. rewarding yourself every time you get distracted

Question 10

Wise and Robble

Answer 10

there is biological evidence that dopamine can be used in conjunction with classical conditioning to explain how addiction is formed and maintained

Question 11

Olds and Milner

Answer 11

used rats to test addictive potential of drugs. they self stimulated with drugs to exhaustion. led to discovery of ‘pleasure centre’
- Unethical, doesn’t consider wider context, behaviour more complex than pressing a lever

Question 12

methodological issues

Answer 12

nutt et al argues samples too small and substances and environment artificial.

Question 13

development of treatments

Answer 13

varenicline - useful and evidence for effectivneess of dopamine causing addiction
more effective with other treatments,
but more effective compared to others.

Question 14

national institute of health - varenicline

Answer 14

44% abstinence in varenicline group compared to bupropion (30%) and placebo (18%). at one year V- 23%, B- 16%, P- 10%

Question 15

role of dopamine unclear?

Answer 15

unusual levels found in other disorders. high levels correlated with aggression. also works to motivate us to avoid bad situations. found increased dopamine activation in PTSD sufferers

Question 16

not all addictive behaviours increase dopamine

Answer 16

stokes - no sig increase in dopamine in cannabis users. Yoder - same with alcohol
inconsistency is research suggests its not a comprehensive explanation

Question 17

conclusion

Answer 17

treatments but
2512 in south wales drugs to help opioid dependency, cost effeicient. doesnt explain uneven dispersion of addicts in low income, deprived areas. socio-economic factors important