Mental changes experimentally produced by d-lysergic acid diethylamide tartrate

Introduction

The paper opens with a historical overview of early observations of the effects of d-lysergic acid diethylamide (LSD), beginning with Albert Hofmann's self-observations and subsequent investigations by several clinicians. Earlier experimental work by W. A. Stoll, Condrau, Becker and others is summarised as reporting disturbances in perception (notably visual hallucinations), vegetative and motor symptoms, changes in affect and thought processes, variable disturbance of consciousness but preserved judgement, and a striking potency of very small oral doses. Some investigators emphasised similarities to psychotic syndromes or diencephalic dysfunction, while others highlighted the drug's “psychoticum” qualities and its variable expression across individuals. Miss and colleagues set out to add to this literature by conducting controlled experimental administrations of LSD to healthy adult volunteers, systematically observing the psychiatric picture, autonomic and some neurophysiological measures, and selected psychological tests. The study aimed to characterise the mental changes produced by small oral doses of LSD, describe the time course of the reaction, and explore electrophysiological and psychological correlates that might clarify how the drug affects higher nervous-system function.