Concepedia

Abstract

Motor and mental performance was tested after smoking a placebo cigarette and after smoking a marihuana cigarette calibrated to deliver 5 mg. of delta‐9‐tetrahydrocannabinol. A significant decrement in all motor performance tests and in five of nine mental performance tests was observed after the marihuana cigarette. We were not able to detect any cannabinols in the blood or urine of subjects who smoked the marihuana.