A physiological analysis of dissociative learning against a background of physostigmine and pentobarbital

Physostigmine (0.7-0.8 mg/kg, i.p.) decreased and pentobarbital (13.4-14.6 mg/kg) increased the locomotor and emotional activity of rats in the "open field". Both drugs induced the reversible amnesia to a conditioned reaction in a double T-maze with positive (nutritional) reinforcement. These changes in behavioral activity were correlated with dissociated learning of rats after the injection of the drugs: physostigmine largely decreased the number of errors during learning as compared with pentobarbital. However, in both cases rats reached the learning criterion sooner than the control animals due to the shorter reaction latency (physostigmine) and increase in general motor activity (pentobarbital).