Cognitive control involved in overcoming prepotent response tendencies and switching between tasks.

A dissociable set of regions was active for the executive processing associated with overcoming a prepotent response tendency and task switching. Regions associated with overcoming prepotency were primarily frontal and may be part of a system involved in top-down biasing for conflict reduction. Posterior regions were recruited for switching between tasks and likely play a role in reconfiguring stimulus-response mappings. Precuneus activity was common to both manipulations and may reflect increased visual attention due to more difficult task demands.