Executive dysfunction, self, and ego pathology in schizophrenia: an exploratory study of neuropsychology and personality.

Schizophrenic patients show a variety of symptoms, including positive and negative symptoms and ego pathology. Their exact underlying neuropsychological mechanisms as well as related changes in personality, however, remain unclear. We therefore conducted an exploratory study to investigate the relationship among neuropsychological functions, various dimensions in personality, and the different kinds of psychopathological symptoms. We investigated 22 paranoid schizophrenic patients and 22 age- and sex-matched healthy controls using a battery of neuropsychological, personality, and psychopathological tests and scales. Neuropsychological tests included executive function, working memory, and episodic memory, whereas personality assessment relied on the Temperament and Character Inventory by Cloninger (Arch Gen Psychiatry. 1987;44:573-88). Psychopathological rating included the scales for the assessment of positive and negative symptoms and the Ego Pathology Inventory by Scharfetter (Psychol Med. 1981;11(2):273-80). Schizophrenic patients showed significant deficits in executive function, working memory, and episodic memory. In contrast to healthy subjects, no significant correlation between working memory and executive function was observed in schizophrenic patients. Instead, both working memory and executive dysfunction were rather related to deficits in retrieval of episodic memory. Positive and negative symptoms correlated with episodic memory deficits but not with any dimension of the personality, whereas ego pathology, in contrast, correlated with executive dysfunction and working memory deficits. Moreover, schizophrenic patients showed specific changes in the self-dimensions of their personality, which correlated significantly with both executive dysfunction and ego pathology. Schizophrenic patients show deficits in working memory and executive function as well as functional dissociation between both. In contrast to positive and negative symptoms, ego pathology in these patients is specifically related to executive dysfunction and alterations in the self-dimension of their personality. It can therefore be concluded that ego pathology must be distinguished from positive and negative symptoms in both underlying neuropsychological dysfunction and predisposing changes in personality.