Chlorpromazine effects on brain activity (contingent negative variation) and reaction time in normal women.

Electrical brain activity (contingent negative variation of CNV) and psychomotor behavior (reaction time or RT) were measured after 50 mg of chlorpromazine (CPZ) or placebo were given orally to 28 normal women. CPZ reduced CNV 2 and 3 hrs post-drug and slowed RT 3 hrs post-drug. CNV amplitude appears to be an accurate indicator of drug-produced changes in alertness.