LYSERGIC ACID AND ITS EFFECTS ON VISUAL DISCRIMINATION IN MONKEYS

Abstract

Lysergic acid diethylamide (LSD-25) administered to monkeys in small dosage has clear effects on tachistoscopic perception. These effects are verified in the two studied variables (a) the percentage of correct responses in discrimination of briefly presented visual cues, and (b) the reaction time to the presentation of these cues. While the percentage of correct responses is lowered, the reaction time is considerably increased by the drug. The effects are proposed to be explained by an inhibitory action of the drug upon the axodendritic synapses of the central nervous system. A LSD-25 inhibition of the cortical terminal synapses of the cerebral reticular structures appears to be corroborated by the results of the present behavioral study.