Brain abnormalities may explain predisposition to drug addiction

Scientists have discovered brain abnormalities which could help explain why some people are more prone to drug addiction. The findings suggest that the make-up of certain people’s brains could mean they have a predisposition to substance abuse.

Researchers at the University of Cambridge have identified the abnormalities in the frontal lobe of cocaine users’ brains which are linked to their compulsive cocaine-using behaviour. Led by Karen Ersche, the researchers 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 which was directly related to the duration of their cocaine abuse, and that this reduction in volume was associated with greater compulsion to take cocaine.

The scientists also found that parts of the brain reward system where cocaine exerts its actions were significantly enlarged in cocaine users. This was not linked to the duration of the user’s habit. 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.