Comparative Lucid Intervals After Amobarbital, CO2, and Arecoline in the Chronic Schizophrenic

Introduction It has been found by numerous investigators that reserpine inhibits the conditioned avoidance response in animals. When administered to man, reserpine produces symptoms of parasympathetic (muscarinic) stimulation. With these two facts in mind, Pfeiffer and Jenney¹tested the effect of certain tertiary amine muscarinic stimulants on the conditioned avoidance responses of rats protected peripherally with atropine methylnitrate. The drugs arecoline, pilocarpine, and physostigmine were found to be effective inhibitors of the conditioned avoidance response. To test the correlation between the inhibition of the conditioned avoidance response in animals and the production of "lucid intervals" * in schizophrenic patients, arecoline was administered to schizophrenic patients. Two-thirds of the patients showed an apparent reversal of the schizophrenic symptoms for a period of 15 to 20 minutes. Several of the arecoline-induced lucid intervals appeared as dramatic as those produced by the administration of amobarbital sodium (Amytal sodium) or by the inhalation of