An abnormality that makes it more difficult to exercise self-control has been identified in the brains of drug addicts, as well as their siblings who have no history of addiction.
Researchers at the University of Cambridge scanned the brains of 50 pairs of brothers and sisters. One in each pair was dependent on cocaine while the other did not abuse drugs or alcohol. Their brains were then compared with those of 50 unrelated healthy volunteers who had no personal or family history of drug addiction.
The researchers found that siblings shared the same abnormality in the parts of the brain associated with how we control behavior, known as the fronto-striatal systems. This kind of abnormality is typically seen in people who struggle with drug addiction, researchers note.
“It has long been known that not everyone who takes drugs becomes addicted, and that people at risk of drug dependence typically have deficits in self-control,” said Dr. Karen Ersche, of the Behavioural and Clinical Neuroscience Institute (BCNI) at the University of Cambridge.
“Our findings now shed light on why the risk of becoming addicted to drugs is increased in people with a family history of drug or alcohol dependence.
“Parts of their brains’ underlying self-control abilities work less efficiently. The use of addictive drugs, such as cocaine, further exacerbates this problem, paving the way for addiction to develop from occasional use.”
She noted it’s “intriguing” that siblings who don’t abuse drugs show similar brain abnormalities.
“While we still have more work to do to fully address the reasons why some family members show a greater resilience against addiction, our results will provide the scientific basis for the development of more effective preventative and therapeutic strategies for people at risk of addiction,” she said.
The next step will be to explore how the siblings who don’t take drugs manage to overcome their brain abnormalities in their daily lives, according to researchers. A better understanding of what may protect them from drug abuse may provide clues for developing more effective therapies for those trying to beat addiction, researchers conclude.
Source: University of Cambridge