Tests show drug attacks willpower

BRAIN scans carried out by Irish researchers have revealed that cocaine attacks the willpower and judgment of people addicted to the drug.

Scientists at Trinity College Dublin have used sophisticated imaging equipment to show cocaine alters parts of the brain responsible for controlling behaviour and judging risk.

A research team in Trinity College — led by Dr Hugh Garavan — carried out research on dependent cocaine users in the US, involving the administration of pure cocaine in hospitals, followed by a series of computer tasks aimed at measuring impulse control. This was then compared against a control group of non-users.

The results were analysed at the Trinity’s Institute of Neuroscience using functional Magnetic Resonance Imaging (fMRI).

“What we’re finding is that cocaine users seem to be compromised in the brain regions,” said Dr Garavan.

“There are critical regions in the frontal lobes involved in impulse control and we find those regions have reduced activity in cocaine users.

“Similarly, in other brain regions involved in monitoring behaviour — say if you are about to do something risky and making a judgment — those regions also show reduced activity.”

He said only about 15-20% of cocaine users end up being hooked on the drug.

“The critical issue is why do some people go from being a recreational user to becoming a dependant user? Part of it, clearly, is to do with underlying biology,” said Dr Garavan.