Task Switching: Mechanisms Underlying Rigid vs. Flexible Self-Control

This chapter reviews the historical and current literature on task switching, focusing primarily on cognitive-behavioral studies on healthy human subjects. It outlines what I see to be widely accepted conclusions. These include the notion that tasks have mental representations ("task sets") and that a change in this representation results in slowing (although the exact reasons for the slowing are debated). Following Ach (2006/1910), the chapter divides the processes that are currently mentioned in the literature into those making an inner obstacle against a task switch (thus causing rigidity) and those that enable a task switch (thus supporting flexibility). It also discusses some major controversies in the field and suggest that many of these controversies are more apparent than real by pointing out the many issues where a broad consensus exists.