The broad, long-term goals of this program of research are to identify the pathophysiological processes underlying schizophrenic disordered speech. The specific goals of the proposed study are (1) to identify communication disturbances in the speech of people with schizophrenia using the Communication Disturbances Index (CDI), a recently developed "natural language" measure that assesses six different types of referential communication disturbances, (2) to test for associations between the different types of communication disturbance and specific neuropsychological deficits, and (3) to assess the stability of each type of communication disturbance over time and across clinical state. In the proposed study three speech samples would be collected over six months from each of 60 schizophrenia outpatients and 40 control subjects. A battery of neuropsychological tests specifically designed to measure facets of working memory, sustained attention, and other areas of cognitive functioning potentially related to communication disturbances also would be administered. Levels of each type of communication disturbance would be compared between groups. Associations between performance on the neuropsychological tests and each type of communication disturbance would be examined within and between groups. The within group analyses would control for differences among subjects in global verbal intelligence and, in the patients, in global severity of illness. The proposed study would attempt to confirm preliminary findings of connections between impairments in working memory and sustained attention, and particular kinds of communication disturbances in schizophrenia. Stability of CDI ratings over time and across clinical state also would be examined, with the expectation that those types of disturbances most highly associated with working memory deficits would be most stable over time and across state. The proposed study could help to elucidate the cognitive underpinnings of particular types of communication failures in schizophrenia. It also could assist in differentiating between "state" vs. "trait" forms of communication impairment, thereby contributing to the effort to discriminate potential vulnerability markers from state-specific episode markers in schizophrenic language symptoms. Undergraduates would be involved in rating the speech samples, scoring and entering the neuropsychological tests, analyzing the data, and reporting the results.