Examining the Independence of Flanker and Simon Effects in the Auditory Modality

When tasks require the processing of conflicting information, it is the role of the executive system to resolve this conflict and enable successful task completion. Common tasks for studying conflict resolution include Simon, Stroop, and flanker tasks, among others. Although these tasks are conceptually similar, there is evidence both for and against the notion that they tap the same neural resources. The present study extends this debate by examining the overlap between auditory Simon and flanker tasks. Thirty-eight young adults completed a combined auditory conflict task, in which two simultaneous voices (target and flanker) spoke the words “right” or “left” in the same ear to evoke a lateralized response. While both ear-response (Simon) conflict and target-flanker conflict significantly slowed response times and decreased accuracy, the Simon effect was very weak. Effects of conflict on response times were additionally qualified by an interaction in which the Simon effect was only present for congruent flanker trials. The results might suggest either shared neural resources, or modulation of the Simon effect by the attentional demands of the auditory flanker task.