A new study has found that chronic cocaine use is associated with abnormal brain structures. Researchers from the University of Cambridge, led by Dr. Karen Ersche, examined the brains of 120 people, half of whom were addicted to cocaine.

The study found that the cocaine users had widespread loss of gray matter in the frontal lobe, which was directly related to their cocaine use. The longer the participants had been using cocaine, the greater the loss of gray matter. This reduction was also associated with greater compulsivity to use the drug.

The researchers also found that parts of the brain’s reward system, which is associated with addiction and drug cravings, were significantly enlarged in cocaine users. The enlargement was not related to duration of cocaine use, however, which suggests that changes in the brain’s reward system predate cocaine use, possibly making some individuals more vulnerable to the effects of the drug.

Dr. Ersche, of the Behavioural and Clinical Neuroscience Institute (BCNI) at the University of Cambridge, said that the study provides insight into why some people are more vulnerable to drug addiction than others. She added that the study could be important for future development of effective treatment for those who are addicted to cocaine, and could help inform strategies to prevent drug addiction.

Many people who are addicted to cocaine describe feeling a compulsion to use the drug. This study may help people better understand cocaine addiction and why this compulsion occurs, Dr. Ersche added.

The study also demonstrated that changes in other brain structures of chronic cocaine users were associated with debilitating attention problems. Dr. Ersche said that these findings are important because they show a defined relationship between the brain, the duration of cocaine use, and the common attention problems often reported by those who are addicted to cocaine.

Dr. Ersche added that their study shows that cocaine addiction is a disorder of the brain, which is important information for the treatment of those who are trying to recover from cocaine addiction.

The researchers plan to examine whether there is an inherited vulnerability to cocaine addiction. Although cocaine is a highly addictive substance, not everyone who uses it becomes addicted. The researchers plan to look at whether people with an enlarged reward system in the brain are at a greater risk of becoming addicted to cocaine.

Source: Science Daily, Abnormal Brain Structure Linked to Chronic Cocaine Abuse, June 22, 2011