Neural mechanism of conflict control in a number interference task.

The electrophysiological bases of conflict control in a number interference task was measured in 21 healthy study participants using event-related brain potentials (ERPs). In the number interference task, participants were instructed to ignore the number words meaning and to report the number of the number words. The number words were 'two', 'three', or 'four'. We focused on the differences between the incongruent condition (e.g. 'two' written four times) and the congruent condition (e.g. four written four times). Scalp ERP analysis revealed that the incongruent condition elicited a more negative ERP deflection (N350-470) than the congruent condition between 350 and 470 ms, and a more late positive deflection (LPC) than the congruent condition between 550 and 650 ms. N350-470 was a critical sign of conflict monitoring in the early phase, and LPC mirrored conflict resolution in the terminal stage. The results provided evidence for the dissociation between conflict monitoring and conflict resolution in the number interference task.