Medical students and drugs: further neuropsychological and use pattern considerations.

Drug use patterns of 134 freshman medical students were surveyed. Ninety-four percent reported experience with alcohol, 72% with marijuana, 24% with hallucinogens or stimulants, and 7% with opiates. Persons who reported use of the least socially sanctioned substances (hallucinogens, stimulants, opiates) were a subgroup of marijuana users, whereas marijuana experienced students were a subgroup of alcohol users. Increasing marijuana use appears to be associated with increased alcohol consumption. Twenty-five students who had never used marijuana and 26 students who had used it on 50 or more occasions were compared on three neuropsychological tests: Tactual Performance Test, Minnesota Perceptuo-Diagnostic Test, and the Hutt Adaptation of the Bender Gestalt Test. There were no neuropsychological differences between marijuana experienced and marijuana naive subjects. The methodological difficulties in studying the long-term cerebral effects of marijuana are discussed.