Toward a Definition of the Schizoid State: Evidence from Studies of Twins and Their Families

Abstract

Over the years investigators have described psychiatrically abnormal individuals in the families of schizophrenics. These unusual persons have been given a variety of names: schizoids, schizoid psychopaths, and the condition called schizoidia or schizophrenia-spectrum illness (Kahn, 1923; Planansky, 1966). With recent developments in family and adoptive studies of schizophrenia which have indicated a genetic factor playing a causative role, the schizoid state has assumed more importance, especially in estimating the type of inheritance (Heston, 1970). Furthermore, the schizoid state is of considerable interest from a clinical standpoint since it may represent a ‘forme fruste’ of schizophrenia, and as such a study of schizoids from the point of view of the factors which may have prevented a full-blown schizophrenic process would be of great interest.