Cognitive and behavioral effects of cholinergic, dopaminergic, and serotonergic blockade in humans

Abstract

The purpose of this study was to investigate the cognitive and behavioral effects of anticholinergic, antidopaminergic, and antiserotonergic agents given alone and in combination to normal volunteers. Twelve young male volunteers took part in this double-blind randomized, placebo-controlled, crossover study of six drug conditions, each administered on separate days [haloperidol (2 mg PO) ± scopolamine (0.5 mg IV), metergoline (4 mg PO) ± scopolamine (0.5 mg IV), placebo, and scopolamine alone (0.5 mg IV)]. Scopolamine-induced sedation (p