Local build-up of sleep pressure could trigger mind wandering: evidence from sleep, circadian and mind wandering research

Abstract

Mind wandering (MW) or having thoughts unrelated to the task at hand is a very pervasive phenomenon. Although research on MW has exponentially grown during the last decade and a half, the mechanisms behind this omnipresent phenomenon remain largely unknown. In this review, we will discuss some factors that have been shown to contribute to the occurrence of MW: the quality of sleep, the time of day when the task is performed, the chronotype of the individual and the duration of the task. The intriguing commonality between these specific factors is that they all suggest a relation between MW and “fatigued” brain states. This suggestion nicely fits a recent proposal that related MW to local “fatigued” brain areas involved in task performance. We will argue that one of the mechanisms underlying the pervasiveness of MW might be the local build-up of homeostatic sleep pressure that inevitably occurs during task performance in the brain areas related to the task.