BrainTalks

Thinking about things that are absent from the perceptual moment is core to multiple aspects of human cognition. Such “stimulus-independent” cognition is essential in tasks with complex time varying rules, but also when our minds wander from the here and now and we revisit the past or imagine possible futures. We used magnetencephalography (MEG) to test the hypothesis that these superficially different types of cognition share a common reliance on alpha oscillations to allow cognition to be guided by internal information (stimulus-independent thought). Alpha power increased preceding fast accurate actions more for those dependent on representations of prior task events. Alpha power was also high during prospective and retrospective off-task states (identified via experience sampling), but only when tasks are easy because appropriate actions are determined by immediate sensory input. Our study establishes alpha oscillations support different types of perceptually decoupled states in a flexible, context-specific manner.