Abstract
Monitoring actions and outcomes is essential for flexible adaptation to environmental demands. Information about errors is important regardless of whether it is internally generated or externally signaled. Following incorrect responses, an event-related potential (ERP) component known as error-related negativity (ERN) appears in electroencephalographic (EEG) signals and reflects activity of the performance monitoring system located in the posterior medial frontal cortex (pMFC). Another ERP component associated with performance monitoring, feedback-related negativity (FRN), has been shown to process feedback stimuli related to performance errors. However, unlike the ERN, which is elicited by errors that may not reach conscious awareness, it remains unclear whether the FRN is modulated by unconsciously perceived errors. To examine modulation of the FRN by objective and subjective response correctness, EEG was recorded from 28 participants performing a digit-entering task that included trials with false feedback. Single-trial EEG analysis using linear mixed-effects models revealed that FRN amplitudes were modulated by objective response correctness after controlling for subjective reports of error certainty. Response time in the subsequent trial was also influenced by objective correctness, although no behavioral measure fully aligned with ERN or FRN patterns. These findings suggest a common representation of objective correctness in response- and feedback-related pMFC activity.