ABSTRACTThe study was design to assess the hypothesis that preference for visual stimulation is at least in part determined by physiological mechanisms which can be modified by depressant and stimulant drugs. Thirty‐six undergraduate females representing stable extroverts and stable introverts were used under diversive and specific exploration paradigms. While the specific exploration paradigm failed to reveal drug effects, the diversive exploration paradigm revealed that preference patterns of introverts were influenced by chlorpromazine, while dextroamphetamine sulfate had no significant effect on the preference patterns of extraverts. The relationship between the RAS, cortical arousal, and preferences for stimulation is discusse