The functional significance of symptomatology and cognitive function in schizophrenia.

The relationships between positive and negative symptomatology, cognitive function, and the ability to perform basic activities of daily living in patients with schizophrenia were examined in two studies. In study 1, 112 medicated patients were assessed utilizing the Brief Psychiatric Rating Scale (positive symptoms), the Negative Symptom Assessment (negative symptoms and cognitive function), and the Functional Needs Assessment (activities of daily living). Study 2 (n = 41), utilized the same measures of symptomatology and added a comprehensive neuropsychological test battery. Regression analyses in both studies determined that symptomatology predicts a relatively small amount of the variance in the ability to perform basic activities of daily living. Cognitive function, whether assessed with the Cognition subscale of the Negative Symptom Assessment or a comprehensive neuropsychological test battery, predicted over 40% of the variance in scores on the Functional Needs Assessment. A path model in which cognition predicted both concurrent symptomatology and activities of daily living and where symptomatology had little direct impact upon activities of daily living fit the data. The importance of addressing cognitive deficits in psychosocial intervention programs is discussed.

Relationship between specific types of communication deviance and attentional performance in patients with schizophrenia.

Communication Deviance (CD) characterizes the speech of schizophrenic patients and their relatives. The relationship between specific types of CD as measured from verbatim transcripts of Thematic Apperception Test protocols and attentional performance was investigated in 27 patients with schizophrenia. Assessments were conducted just prior to hospital discharge. Results revealed that a continuous performance attentional test with visually presented stimuli was most highly related to the CD factor indicating that the respondent had misperceived elements of the card. A continuous performance attentional test with auditory stimuli was found to be associated with the factor reflecting odd language use in the speaker. A measure of selective attention/executive control, from the Stroop Color-Word test, was found to be most highly related to the CD factors which involve higher level functions such as abstraction and integration of various elements of the card into a coherent story. Results suggest that CD may be a behavioral consequence of deficits in attention and executive control, and add to the growing literature suggesting that specific types of neuropsychological deficits can be linked to specific overt behaviors.