Lack of a Long-term Effect of LSD on Y-maze Learning in Mice

Abstract

IT has recently been reported that lysergic acid diethylamide-25 (LSD) has an inhibitory effect on T-maze learning in mice¹. The animals were tested 2 min after an intraperitoneal injection of LSD, in view of the observations of Uyeno and Benson that the effect of LSD on agonistic behaviour approaches a maximum 5 min after injection². Because of the controversy regarding potential long-term psychological effects of LSD, we had undertaken an examination of the effect on learning a shock avoidance task by repeated treatment of mice with increasing quantities of LSD over a long period. We report here the effect of this regimen on Y-maze learning in mice.