DSM-III implications of the diagnoses of catatonia and bipolar disorder

Although catatonia has traditionally been thought of as a type of schizophrenia, the author presents studies indicating that catatonia may be at least as common in bipolar disorder as it is in schizophrenia. He points out that changing definitions of schizophrenia and affective disorder require a reassessment of catatonia and its incorporation in modern diagnostic systems. The discussion represents material presented at the Affective Disorders Advisory Committee of the American Psychiatric Association Work Group to Revise DSM-III.