addiction Flashcards
who suggested the 6 criteria’s?
Mark Griffiths
what are the 6 criteria?
salience
tolerance
relapse
conflict
withdrawal symptoms
mood modification
what is salience?
the activity becomes the most important thing and it dominates their thoughts
what is tolerance?
as they continue to engage in the behaviour they will need more and more in order to achieve the same desired effects
what is relapse?
addicts will revert back to the behaviour after a long period of abstinence
what is conflict?
addicts will often experience a breakdown in relationships and a personal struggle as they continue to engage in the behaviour
what are withdrawal symptoms?
if the behaviour is stopped the individual will experience uncomfortable side effects. these can either be physical or psychological
what is mood modification?
when they engage in the behaviour they can experience a ‘buzz’ or a ‘high’ but this could also be a sensation of escape or numbness
what are the 2 biological explanations to addiction?
dopamine hypothesis
genes
what does the dopamine hypothesis suggest?
addictive behaviours and substances trigger the release of dopamine in the mesolimbic pathway
what is the mesolimbic region responsible for?
providing us with the sensation of reward
where does dopamine travel in the mesolimbic pathway?
from VTA to nucleus accumbens
what is the VTA?
what does it stand for?
ventral tegmental area
one of the key dopamine producing areas in the brain
what is the nucleus accumbens responsible for?
strongly associated with motivation and reward
what is the name of the other pathway and where does dopamine travel in this?
mesocortical
from VTA to the pre frontal cortex
what is the pre frontal cortex responsible for?
creating long lasting memories
what is the incentive sensitisation theory?
what are the names of the researchers?
repeated exposure to the drugs of abuse leads to increasing sensitivity of the brain to their desirability
Robinson and Berridge
what is down regulation?
what does this create?
what can it lead to?
- continued exposure eventually results in a reduction of the activity of positive reward circuits and the dopamine receptors become less sensitive to the effects
- creates a chronic stress (withdrawal symptoms)
- leads to tolerance
what is a strength of the dopamine hypothesis?
(hint: B&B)
what does this suggest?
- practical applications that result in effective treatments
- Botswick and Bucci describe the treatment of a young adult male patient who was addicted to sex.
- he had a strong appetite for pornography and in his 20s would spend up to 8 hours online searching for ‘sexually gratifying activity’.
- at 24 he was treated with naltrexone which blocked the release of dopamine. blocking the reward resulted in his addiction plummeting and his psychosexual functioning dramatically improved.
- this suggests that the drug therapies created in response to the dopamine explanation can go some way in improving the lives of real people
what is another strength of the dopamine hypothesis?
what does this explain?
- supportive research evidence which can account for individual differences in addictions
- Volkow et al gave Ritalin (gently lifts dopamine levels) to a group of adult volunteers. some loved the feeling of the drug but others didn’t.
- they then produced brain scans and found that those who liked the drug had fewer dopamine receptors than those who hated it.
- this explains why some people may go on to develop an addiction after experimenting with drugs whilst other with the same initial experience will not.
- this reflects real world human behaviour
what is a weakness of the dopamine hypothesis?
(hint: 2x evidence)
what does this suggest?
- there are significant shortcomings - not all addictions seem to increase dopamine levels.
- Stokes et al found no significant increase in levels of dopamine in volunteers taking cannabis.
- Yoder et al found no consistent increase in dopamine across the pps in their study who were given alcohol.
- this suggests that we must proceed with caution when suggesting that all addictions can be attributed to the action of dopamine on the brain, when apparently this is not the case.
what is another weakness of the dopamine hypothesis?
- explaining addiction as being wholly due to the action of dopamine is far too simplistic and fails to recognise that dopamine has a range of other functions.
- Lierzon et al showed increased activation in the mesolimbic pathway of war veterans suffering from PTSD when reminded of battle through combat sounds.
- Such findings are in direct opposition of what we would predict about dopamine if we are to believe that its action is responsible for addictive behaviours
what did Goldman et al conclude when studying genes?
what are the figures?
‘addictions were moderately to highly heritable’
ranges from +0.39 for hallucinogens to +0.72 for cocaine
what is the name of the specific gene?
DRD2 gene (D2 dopamine receptor gene)