Studies in the Effects of Lysergic Acid Diethylamide (LSD-25): Visual Perception of Verticality in Schizophrenic and Normal Adults

This study is concerned with the effect of change in organismic state, induced by a pharmacological agent, upon spatial localization. Aside from the current concern with the psychological effects induced by the drug, d-lysergic acid diethylamide (LSD-25)* the problem has its roots in two lines of investigation: 1. Studies of perception viewed in terms of an organismic theory of behavior, viz., sensory-tonic field theory of perception. 2. Studies of perception from the comparative and developmental point of view; here, the effect of this drug is significant because previous investigations have found that it produces primitive behavior in normal adults.^1,4,6,8

Sensory-tonic theory of perception, within which the present study was conceived, stands in contrast to traditional theories, which treat perception as a relatively isolated event. According to sensory-tonic theory, perception is held to be not simply a function of stimulus conditions but, rather, a function of the relations obtaining