Neural aftereffects of errors in a stop-signal task.

In order to maintain goal-directed behavior in a changing and distractive environment, one needs to continuously monitor one's own performance and adjust it in case of unfavorable outcomes. One aspect of behavioral adjustment commonly observed in reaction time tasks is an increase in response time in trials following an error, referred to as post-error slowing (PES). Using a stop-signal task with a four-on-two stimulus-response mapping, we here investigated the neural aftereffects of stop-errors. We examined oscillatory activity in the inter-trial interval as well as event-related potentials (ERP) in the next trial. Behavioral results speak against general adjustments after stop-errors as post-error behavioral changes could be attributed to stimulus or response repetitions. This corresponded with ERP effects in the next trial with only the visual N1 showing an effect of previous trial type and both N2 and P3 showing an effect of stimulus repetition. During the inter-trial interval, we observed stronger and later occipital alpha power increase after stop-errors compared to go- or inhibited trials. Errors also elicited enhanced frontal beta power relative to stop-trials and by trend to correct go-trials, which largely returned to baseline before the onset of the next trial. These transient changes in the neural aftereffects of stop-errors might be related to previous behavioral observations of PES after short, but not long response-stimulus intervals.