Effects of chronic cocaine abuse on memory and learning

Sixteen chronic (M = 5 years) weekly cocaine users who were at least 10 days (M = 20 days) abstinent were compared to age, education, race, and gender matched controls on the California Verbal Learning Test, Wechsler Adult Intelligence Scale-Revised (WAIS-R) Vocabulary, and Block Design. Subjects with developmental disorder, neurological, psychiatric, or other substance abuse history were excluded. Cocaine subjects learned and recalled fewer words than controls, but did not differ on IQ. Results suggested significant residual impairment in verbal learning efficiency subsequent to chronic cocaine use that results from memory storage difficulties rather than attentional impairment or general intellectual reduction. A dose-response relationship is suggested.