Event-related brain potential signaling unexpected timing of feedback: A source localization analysis

Mediofrontal event-related potential (ERP) components have been extensively reported following performance error or unexpected feedback, and could reflect dopaminergic phasic changes conveyed to medial prefrontal cortex. Recent studies suggest a role for medial prefrontal cortex not only in signaling unexpected feedback but also unexpected timing of expected feedback. However, analyses of this aspect are still scarce. In this study, a task creating a condition of unexpected (anticipated) timing of a predicted feedback was designed and the associated ERP analyzed. Both an aversive and a neutral feedback were considered. ERP analysis evidenced frontocentral component elicited by unexpected, relative to expected, timing of feedback, more significant for aversive than neutral feedback. Cortical generators of this ERP component were estimated using sLORETA source localization method: we found that some regions in the frontal and prefrontal cortex may be responsive to unexpected timing of feedback, to a larger extent in case of aversive than neutral feedback. Results are discussed with respect to findings of previous works. This study can contribute to inform current theories of performance monitoring in frontal/prefrontal cortex and to drive future investigations.