Proactive and reactive control in S-R compatibility: A brain potential analysis


  • This work is part of the research program with Grant 400-03-392, which is financed by the Netherlands Organization for Scientific Research (NWO). Maurits van der Molen was supported also by a grant from the Netherlands Institute for Advanced Study for Humanities and Social Sciences (NIAS).

Address correspondence to: Geert van Boxtel, Department of Psychology, Tilburg University, Postbus 90153, 5000 LE, Tilburg, The Netherlands. E-mail:


We investigated how proactive and reactive control facilitates performance in mixed stimulus–response compatibility (SRC) tasks. SRC effects were eliminated in mixed tasks and reversed following incompatible trials. In mixed tasks, early preferential response activation was present in stimulus-locked lateralized readiness potentials (LRPs) but reduced following incompatible trials. In event-related potentials (ERPs), stimulus-locked N2 was enhanced in all mixed trials but was not significantly influenced by the preceding trial. A response-locked fronto-central negative component (N-120), peaking just before the response, was largest for mixed compatible trials preceded by incompatible trials. This N-120 was paired with an enhancement to the peak of the response-locked LRP. Proactive control is involved in selection of an S-R mapping via the indirect route of a dual-route model. Reactive control corrects the S-R mapping, particularly when alternating between S-R mappings.