Chronic, heavy cocaine use associated with long-lasting impaire...( ndividualswho had used cocaine at leas...),Health

This group was compared to a control group of 21 individuals with no history of drug use except perhaps nicotine, who said they had not had more than 4 drinks of alcohol in the past 30 days. Cocaine users and controls were similar with respect to age, education, and intelligence. None had any current or past history of psychiatric disorder.

The cocaine users were interviewed about how long they had been using cocaine, how many times per week they used it, and their weekly intake in grams. They were admitted to the NIDA Clinical Inpatient Research Unit, where they remained drug free for 30 days.

The cocaine users were given a battery of neuropsychological tests on the 28th or 29th day after admission to the research unit. Those who reported the heaviest use, as measured by grams per week, performed much worse in most aspects of the testing than did light or moderate cocaine users and non-users.

Dose-related effects were seen primarily on tasks involving the prefrontal cortex, which is the area of the brain most responsible for attention/concentration, planning, and reasoning. The heaviest cocaine users showed slower median reaction times and poorer attention and concentration.

'"/>

Contact: Beverly Jackson and Michelle Muth
MMUTH@ngmsmtp.nida.nih.gov
301-443-6245
NIH/National Institute on Drug Abuse
1-Aug-1999