Negative Symptoms, Tardive Dyskinesia and Depression in Chronic Schizophrenia

Abstract

The existence of a definable and distinct negative syndrome within schizophrenia remains to be established (Barnes & Liddle, 1989). Addressing this issue, Sommers (1985) discusses three stages required to demonstrate validity for a syndrome. These are first, that the signs and symptoms must be shown to occur together. Second, operational definitions must be developed which will reliably identify and rate and features, and third, the relationships between the syndrome and other variables must be shown to be predictable. With respect to the second and third stages, this paper reports briefly on two recent studies which explored the relationship between negative features and other clinical features, specifically depressive symptoms and drug-induced movement disorder. The results of such studies (see also McKenna et al; and Lindenmayer & Kay, this volume) allow some assessment of the ability of the rating methods used to discriminate between negative symptoms and features such as drug-related bradykinesia and depressive features.