Abstract
Background
Whether mismatch negativity (MMN) is associated with clinical status or reflects the disease progression in first-episode psychosis (FEP) patients has not been established. We aimed to investigate whether the change in MMN impairment fluctuates with the change in clinical status during 1-year.
Methods
MMN and the clinical status of 25 patients with FEP were measured at baseline and reassessed after 1 year. MMN of 25 matched healthy controls (HCs) were measured at baseline. Repeated-measures analysis of variance (ANOVA) was used to compare MMN at baseline among the groups, and paired t-tests were utilized to compare baseline and 1-year MMN amplitude of FEP. To identify the association between MMN impairment change and symptomatic, cognitive or functional change during 1-year, this study used multiple regression analysis controlling possible confounders.
Results
MMN amplitudes at baseline were significantly attenuated in FEP patients compared to HC. One-year follow-up MMN amplitude decreased significantly at Fz electrode site in FEP group. Also, the change in MMN amplitudes significantly correlated with the worsened TMT-B but did not with the symptomatic or functional recovery.
Discussion
These results suggest that MMN impairment may be more closely related to cognitive deficits reflecting disease progression than the currently apparent symptoms and functional status during the beginning of a psychotic episode. Future studies are needed to elucidate the relationship with the disease pathophysiology of psychosis and MMN.