Effects of arecoline and pilocarpine on learning ability in marmosets pretreated with hemicholinium-3.

Common marmosets (Callithrix jacchus) were trained to perform serial reversal position discrimination tasks in a Wisconsin General Test Apparatus. Intraventricular injection of hemicholinium-3 4 h before testing resulted in a profound impairment of position discrimination learning which could be overcome by the intramuscular administration of low doses of the muscarinic agonists, arecoline or pilocarpine.