Personality and psychopathology in schizophrenia: the association between personality traits and symptoms.

Research has indicated that stable individual differences in personality exist among persons with schizophrenia, and that they likely predate the onset of illness. Little is known, however, about whether individual differences in personality are related to levels of psychopathology. This study tested the hypotheses that levels of Extroversion, Neuroticism, and Psychoticism are associated with symptomatology. Accordingly, measures of these dimensions of personality and of symptomatology were obtained simultaneously for 113 male subjects with schizophrenia or schizoaffective disorder. Next, subjects were characterized as having high or low levels on each personality dimension and their scores on the five components of the Positive Negative Syndrome Scale were compared using multivariate and univariate procedures. Results indicate that extroverted subjects had lower levels of Positive, Negative, and Emotional Discomfort symptoms, and higher levels of Excitement symptoms than introverted subjects. Subjects with higher levels of Neuroticism had higher levels of Positive and Emotional Discomfort symptoms than subjects with lower levels of Neuroticism. No differences in symptoms were found among subjects with higher versus lower levels of Psychoticism. Results suggest individual differences in personality are associated with psychopathology in schizophrenia and may help further explain the heterogeneity widely observed in this disorder.