Longitudinal relationships between mismatch negativity, cognitive performance, and real-world functioning in early...

Area of Science:

• Neuroscience
• Psychiatry
• Cognitive Science

Background:

• Reduced mismatch negativity (MMN) is a known biomarker in early psychosis (EP).
• Longitudinal relationships between MMN, cognition, and functioning in EP require further investigation.
• Diagnostic specificity of MMN deficits in EP, particularly between schizophrenia-spectrum (SZ) and bipolar disorder (BD), is not well-established.

Purpose of the Study:

• To examine the longitudinal changes in MMN, neuro-cognition, social-cognition, and functional measures in EP patients over one year.
• To determine the diagnostic specificity of MMN abnormalities in SZ versus BD.
• To investigate the associations between MMN, cognitive, and functional outcomes in EP.

Main Methods:

• 54 EP patients (24 SZ, 30 BD) and 42 healthy controls underwent baseline assessments of MMN, neuro-cognition, social-cognition, and functioning.
• 30 EP patients completed 12-month follow-up assessments.
• Longitudinal comparisons of MMN, correlational analyses, and predictive modeling were conducted.

Main Results:

• EP patients exhibited significantly reduced MMN compared to controls at baseline.
• MMN remained impaired in SZ patients at both baseline and follow-up, while BD patients showed no significant MMN differences from controls.
• MMN was associated with symptom severity and functioning at baseline, and with social cognition and functioning at follow-up, but did not predict future functional outcomes.

Conclusions:

• MMN abnormalities are characteristic of early psychosis in schizophrenia-spectrum disorders but not bipolar disorder.
• While MMN is cross-sectionally associated with functioning, it does not predict future functional trajectories.
• MMN deficits are linked to social cognition impairments, suggesting potential downstream effects on community functioning and targets for intervention.