Preclinical Behavioral Approaches to the Identification and Study of Antipsychotic Drug Action and Schizophrenia

Schizophrenia is a group of illnesses of unknown origin with a yearly prevalence of 0.4–0.8% in the general population (Dohrenwend, 1980). Schizophrenia is characterized by a spectrum of symptoms that are commonly grouped into positive (including hallucinations, incoherence, delusions, distorted thought, and incongruity of affect) and negative (including poverty of speech, flat affect, low social drive, curbing of interest, and diminished sense of purpose) categories (Crow, 1980; Berrios, 1985; Kane, 1993a).