Addiction due to abnormal brain structure
Washington: A new study has found abnormal brain structures in the frontal lobe of cocaine users’ brains that are associated to their compulsive cocaine-using behaviour.
Researchers at the University of Cambridge led by Karen Ersche scanned the brains of 120 people, half of whom had a dependence on cocaine.
They found that the cocaine users had widespread loss of grey matter that was directly related to the duration of their cocaine abuse (i.e. the longer they had been using cocaine, the greater the loss of grey matter), and that this reduction in volume was associated with greater compulsivity to take cocaine.
The scientists also found that parts of the brain reward system where cocaine exerts its actions (the basal ganglia) were significantly enlarged in cocaine users; but the size of the enlargement was not related to the duration of cocaine use.
The researchers believe this may suggest that alterations in the brain``s reward system predate cocaine abuse, possibly rendering these individuals more vulnerable to the effects of the drug.
“This research gives us important insight into why some people are more vulnerable to drug addiction. Not only is this important for the future development of more effective therapeutic interventions for people who have become dependent on drugs, it will also inform improved strategies to prevent drug addiction in the first place,” said Ersche, of the Behavioural and Clinical Neuroscience Institute (BCNI) at the University of Cambridge.
The researchers also showed that changes in other brain structures of chronic cocaine users were linked to debilitating attention problems.
Ersche added: “These data show that cocaine dependence is a disorder of the brain, which is very relevant information for the treatment of people who are trying to beat their addiction.”
The study was published 21 June, in the journal Brain.