Mismatch negativity, social cognition, and functioning in schizophrenia patients.

BACKGROUND Cognition and social cognition have been found to influence functional outcome in schizophrenia patients. However, little is known about the underlying neural substrates that are associated with social cognition or daily functioning. Prior studies found associations between mismatch negativity (MMN), an event-related potential response indexing early auditory processing, and functioning in schizophrenia patients. METHODS In this study, we examined MMN, social cognition (social perception and theory of mind), and four domains of functioning (work, independent living, social networks, and family networks) in 33 schizophrenia patients and 42 demographically comparable healthy control subjects. RESULTS Schizophrenia patients exhibited reduced MMN activity at frontocentral electrode sites compared with healthy control subjects. Within the schizophrenia sample, greater MMN activity at frontocentral sites correlated with better work and independent living (but not social or family networks) and with better social perception. CONCLUSIONS These results suggest that MMN activity is more closely tied to some outcome domains (work and independent living) than others. Mismatch negativity has been previously shown to be associated with basic cognition and functional outcome in schizophrenia, but these findings are the first, to our knowledge, to show MMN associations with social cognition. These results are consistent with cascade models of information processing in which deficits in early perceptual processing have a downstream impact on higher order social cognition and community functioning.