COCAINE CONTROL CENTRE FOUND

LONDON - Scientists have identified the part of the brain that may
hold the key to why some cocaine users become addicts while others
just take the drug socially, researchers said today.

Brain scans of cocaine users while they performed simple computer
tasks showed changes in the part of the brain responsible for
controlling behaviour and making appropriate decisions, they said.

This could explain why some people find it easier to quit than others
and may shed light on long-term addiction, said Hugh Garavan, a
cognitive neuroscientist at Trinity College Dublin who presented his
research to a meeting of the Royal Society in London.

"Most people who try to quit drugs relapse," Garavan said in a
telephone interview. "It might have to do with how intact these brain
regions are."

Cocaine, initially used in patent medicines, beverages and tonics
around the turn of the 20th century, is a drug that in powdered form
can be snorted or dissolved in water and injected. Its derivative
crack cocaine is even more powerful.

An estimated one to three per cent of adults in developed countries
use the drug, which has been linked to a number of medical,
psychological and social problems including crime, violence and the
spread of diseases like AIDS and hepatitis, according to the World
Health Organization.

Garavan and colleagues used MRI scans to show that cocaine users had
reduced neural activity marked by reduced blood flow to the portion of
the brain involved in activities such as problem solving, decision
making and controlling behaviour.

Some people were administered cocaine in the course of the
experiments.