Neuropsychological functioning in cocaine abusers with and without alcoholdependence

Thirty codependent cocaine and alcohol users were compared with age-, educa tion; race-, and sex-matched cocaine abusers (N = 30) and normals (N = 30) using an extended Halstead-Reitan Neuropsychological Test Battery to determ ine whether cocaine abusers with alcohol dependence were more cognitively i mpaired than singly addicted cocaine abusers. Tests were grouped and analyz ed according to 8 major ability areas. Participants who abused both cocaine and alcohol did not differ from normals on the majority of test measures. An unexpected but consistent finding was the poorer performance of the coca ine sample relative to cocaine and alcohol abusers on measures of complex p sychomotor and simple motor functioning (ps < .001). Pure cocaine abusers, but not abusers of both cocaine and alcohol, also performed more poorly tha n normals an a measure of global neuropsychological functioning (p < .01). These results are consistent with previous reports of generally mild cognit ive dysfunction in cocaine abusers. The findings also suggest that cocaine and alcohol abusers of relatively young ages may be less cognitively impair ed than demographically comparable cocaine abusers. Evidence from studies o f vascular functioning in abusers of cocaine and alcohol alone and in combi nation is discussed as possible explanation for these findings.