Beyond a blunted ERN - Biobehavioral correlates of performance monitoring in schizophrenia

•External performance monitoring is relatively preserved in schizophrenia.•Underactive internal error monitoring is robustly found in schizophrenia.•Smaller error-related negativity (ERN) is an easy to derive quantification of this finding.•Blunted ERPs are best interpreted as disrupted midfrontal theta activity.•Future work is needed to reveal trial-by-trial dynamics between theta activity and behavior adjustments. Cognitive deficits are well documented in schizophrenia. Here, we reviewed alterations in performance monitoring as potential marker of cognitive deficits in schizophrenia. We found that performance monitoring alterations in schizophrenia are specific to early (indexed by blunted error-related negativity (ERN)) and late (reflected in blunted error positivity (Pe)) internal error processing, while external performance feedback processing in simple response feedback tasks is relatively preserved. We propose, that these performance monitoring deficits may best be interpret as one aspect of disrupted theta band (4−8 Hz) oscillations over medial frontal recordings sites. Midfrontal theta dynamics are an increasingly established direct neural index of the recruitment of cognitive control and are impaired in several clinical populations. While theta-related ERPs (the ERN) may be an easy to assess marker of cognitive deficits in schizophrenia, further work investigating the trial-by-trial dynamics of theta in both the time and time-frequency domain is needed to parse cognitive deficits in schizophrenia into finer levels of detail and evaluate theta modulation as a therapeutic tool.