Differential Behavioral Responsivity to LSD-25: Study in Normal and Schizophrenic Adults

The major question posed in this report is whether chronic schizophrenics show less psychologic response to the administration of a given dosage of lysergic acid diethylamide (LSD-25) than do normal adults. Data relevant to this question are of importance in at least three ways: (1) they are of relevance in delineating the mechanism of action of LSD insofar as such mechanisms—whether psychological, physiological, biochemical, etc—must be broadly enough conceived to encompass differences in effect of LSD in schizophrenics and normals; (2) they provide a fuller picture of similarities and differences between schizophrenics and normals and thereby contribute to a theoretical understanding of schizophrenia; and (3) they contribute to the body of evidence pertinent to the question whether "biochemical sluggishness" is a general characteristic of schizophrenia. The literature concerning the relative responsivity of normals and schizophrenics to LSD-25 is controversial. The several historical