Useful distracting information: ERP correlates of distractors in stimulus-response-episodes.

A basic process in regulating behavior that helps us to disentangle meaningful from distracting information is the binding of stimulus and response features into stimulus-response episodes or "event files". Recent studies have shown that even irrelevant information is bound into event files; distractor repetition on the next trial can trigger the response encoded in this episode, which is indicated by faster reaction times. The present study was conducted to get further insight into the electrophysiological underpinnings of those distractor-based retrieval. For that, we analyzed the N2, a negative deflection in event-related potentials that has been associated with a multitude of processes occurring when relevant and irrelevant stimuli compete with each other within a given trial or even in sequences of trials. Our study showed that distractor which did not provide useful information regarding the required behavior led to more negative N2 amplitudes, whereas distractors that provide useful response-related information were associated with less negative N2 amplitudes. Our results are explained as an adaptive mechanism that helps to hedge against invalid stimulus-response-bindings before an error occurs to increase efficiency of human behavior.