The effect of a small dose of chlorpromazine on a measure of 'cognitive inhibition'

A double-blind drug/placebo experiment was conducted investigating the action of chlorpromazine on ‘cognitive inhibition’ in normal subjects. It has been suggested that such inhibition is reduced in schizophrenics and may be part of the mechanism that gives rise to positive symptomatology, because of a failure to screen out irrelevant material from consciousness. It was found that chlorpromazine (a drug routinely administered to schizophrenics) increased this inhibitory effectsin normal subjects.