The Wandering Mind in Sleep and Wakefulness
Mind-wandering is a mental state in which attention shifts from the present environment or current task to self-referent thoughts about past experiences, future events, or planned actions. A variety of studies estimated that humans spend at least one-third of their waking hours lost in such self-generated mental content. Although mind-wandering seems to reflect a default state of the brain and putatively serves a variety of cognitive functions such as autobiographical memory, creative/divergent thinking, mindreading, or anticipation of future scenarios, excessive mind-wandering comes with high cognitive and emotional burdens. Since mind-wandering is characterized by sensory disengagement and by immersion in internally driven mental processes, it is assumed to be at least partly akin to dreaming experienced during sleep. Accordingly, mind-wandering during attention-demanding cognitive tasks is coupled with neurophysiological indicators of local sleep, supporting the assumption that attentional lapses, sensory disengagement, and spontaneous thoughts are underlined by transient sleep-like neuronal activity. In the present talk, I will summarize two recent studies that build on the above view. The first study examined if daytime mind-wandering could be predicted from the previous night's sleep, specifically the amount spent in sleep stages when intense dreaming occurs. The second study examined the potential benefit of mind-wandering in automatic, implicit learning, opening future avenues to study mind-wandering in relation to information processing and memory consolidation.