Intact Mismatch Negativity Responses in Clinical High Risk for Psychosis and First-Episode Psychosis: Evidence From...

Area of Science:

• Neuroscience
• Psychiatry
• Cognitive Science

Background:

• Mismatch negativity (MMN) is an auditory evoked potential reflecting early sensory processing.
• Investigating MMN in clinical high risk for psychosis (CHR-P) and first-episode psychosis (FEP) is crucial for understanding early psychosis pathophysiology.
• Previous research suggests potential MMN deficits in psychosis, but findings are inconsistent.

Purpose of the Study:

• To examine MMN response integrity in CHR-P individuals and FEP patients.
• To determine if MMN deficits predict clinical outcomes, including transition to psychosis, in CHR-P individuals.
• To utilize magnetoencephalography (MEG) for precise MMN source localization.

Main Methods:

• Magnetoencephalography (MEG) data were acquired using a duration-deviant MMN paradigm.
• Participants included 116 CHR-P, 33 FEP (15 antipsychotic-naïve), 38 high-risk negative controls, and 49 healthy controls.
• Source analysis focused on bilateral Heschl's and superior temporal gyri, examining event-related fields, time-frequency, and intertrial coherence.

Main Results:

• Significant MMN responses were observed in bilateral Heschl's and superior temporal gyri across all groups.
• MMN amplitude, time-frequency, and intertrial coherence were comparable between CHR-P/FEP groups and healthy controls.
• No significant relationship was found between MMN deficits and persistent attenuated psychotic symptoms or psychosis transition in CHR-P participants.

Conclusions:

• Magnetic MMN responses, as measured by MEG, are not impaired in early psychosis (CHR-P and FEP).
• MMN does not appear to be a reliable predictor of clinical outcomes in CHR-P individuals.
• These findings challenge the role of MMN as a biomarker for psychosis risk or progression.