Psychomotor impairment and cognitive disturbances induced by neuroleptics

Reviews of the literature have failed to demonstrate any consistent effects of typical or atypical neuroleptics on psychomotor or cognitive function in schizophrenic patients. Better methods and study designs are required, and healthy volunteer studies are necessary to control for variables due to schizophrenic psychopathology. Eye movements are a sensitive, reliable and relatively pure measure of attention and arousal. Two volunteer studies of the effects of single doses of haloperidol (2,4 and 6 mg), chlorpromazine (50 mg) and remoxipride (100 and 150 mg) on saccadic and smooth pursuit eye movements are described. All drugs impaired both eye movement measures, but the doses used were not clinically equivalent. No available test is yet able to distinguish between benzodiazepines and neuroleptics.