Posts tagged with addiction
September 21, 2012 by Cara Flanagan.
In the search to explain why some people become addicted while others don’t, one answer has been that some people have an addictive personality i.e. they are just more likely to become addicted. Support for this idea comes from the phenomenon of ‘addiction transfer’, described in a recent article by Samantha Murphy in the New Scientist (8 September 2012). Addiction transfer refers to the phenomenon that an addict may manage to overcome one addiction but then develops another as a kind of substitute. The addict appears to need to have an addiction. Accidental evidence for addiction transfer comes from studies of people who have undergone weight loss surgery. Overeating can be regarded as a kind of addiction and weight loss surgery cuts obese people off from their original addiction. Researchers estimate that about 15-30% of those who have undergone weight loss surgery transfer to a new addiction.
The explanation outlined in Murphy’s article is that addiction activates the brain reward system and, when this activation stops, the person looks for something else to maintain activity within this reward system. The genetic link in the addiction transfer explanation is that some people are born with lower levels of D2 receptors, resulting in lower levels of dopamine in the reward system. Addiction behaviour has the effect of increasing their dopamine levels, thus explaining why some people are more prone to becoming addicted. Critically this explains why some people, once they have experienced an addiction, need to continue some kind of addictive behaviour if the original one stops.
March 20, 2012 by Evie Bentley.
Why do people carry on smoking,
and why is stopping smoking so hard to do?
An internal locus of control is when people feels in control of themselves, they feel they can and do affect their own lives, make their own decisions and so on.
An external locus of control is where people feel they don’t have control over their own lives, so that it does not matter what they do or don’t do as it won’t affect them because outside forces and people have the power and make the decisions.
A 2012 USA study has now shown that ‘nicotine dependent’ participants, i.e. people addicted to smoking, are vulnerable to feeling a loss of self-control, to having an external locus of control. The study also found that smoking a cigarette had a double effect, improving mood and restoring a more external locus of control (increased self-control). Clearly this can go some way to explaining why people smoke and why it is so hard to quit the habit. However stopping smoking might be a little less daunting if alternative improving-self-control strategies could be taught, especially if these also raised mood. Suggested strategies include exercise as this puts the person in control and the endorphins released would boost positive mood.
Heckman,B.W., Ditre,J.W. and Brandon,T.H. The restorative effects of smoking upon self-control resources: A negative reinforcement pathway.. Journal of Abnormal Psychology, 2012; 121 (1): 244
January 7, 2012 by Cara Flanagan.
Those of you studying addiction might be interested in a new blog produced by Dr. Mark Griffiths, who is Professor of Gambling Studies at the Nottingham Trent University, and Director of the International Gaming Research Unit. He is internationally known for his work into gambling and gaming addictions, as well as writing about many different kinds of addiction.
His latest post is about whether people can become addicted to their jobs!
September 20, 2011 by Mike Cardwell.
New research suggests that media representation of smoking does influence teenagers to take up the habit. Dr Andrea Waylen and her team at Bristol University examined 360 of the top US box office films released between 2001 and 2005, including those (such as Bridget Jones Diary) that depicted smoking. They found that teenagers who watched films showing actors smoking were more likely to start smoking themselves. Even after controlling for social factors such as whether their parents or peers smoked, the researchers found a significant relationship between adolescent smoking and the number of films they had seen depicting smoking. This has led to the suggestion that in order to cut the numbers of young smokers, films containing scenes of people smoking should be given an 18 certificate.
Watch a discussion of the implications of this research on breakfast television here.
June 12, 2011 by Cara Flanagan.
One of the explanations for addiction is that some individuals have a biological predisposition because they inherit a particular form of dopamine receptor gene (if you want an explanation of dopamine receptor genes see second paragraph). An interesting link has been made between these genes and evolution. The argument goes that the dispersal of our distant ancestors from Africa was related to riskiness. Individuals with a predisposition to be impulsive and risky rather than careful and reflective would be more likely to explore and find new, desirable environments and would also cope better with new, challenging situations. Recent research has indeed found a link between specific dopamine genes and migration patterns i.e. migrants were more likely to have the version of the dopamine receptor gene that codes for risky behaviour. This shows that the gene has had an adaptive function, and may continue to do so.
Understanding dopamine receptor genes: There are different types of dopamine receptor such as D1R, D2R etc. (D for dopamine, R for receptor and the number denotes the type). The receptor is called D1R and the gene for that receptor is called DRD1, or D2R and DRD2 (which seems confusing to me, but there it is). For any gene there are different forms or allelles. So, for example, we all have a gene for D2R but the form of that gene differs. One person may have the G allele (which is associated with aggression) or the 1A allele (associated with addiction). In the study cited above (Matthews and Butler, 2011) the DRD4 gene was studied and the 7R and 2R versions were associated with risky behaviour whereas the 4R version was linked to being even tempered.