In an effort to determine the effects of the drug chlorpromazine on performance of schizophrenics, two clinical investigators randomly selected 20 acute schizophrenics from a mental hospital population. the task used was one that tested the executive and sequencing functions of the frontal lobes. basically several stimuli had to be put in order along a dimension, e. g., eight stimuli had to be ordered as to their weight. there were several tasks of this sort. the investigators used a within subject design in which all subjects first performed the tasks after being injected with a saline solution (placebo) and then performed the tasks again (several hours later) after having been injected with chlorpromazine. results indicated that fewer errors were made in the chlorpromazine treatment which suggested to the investigators that this drug.