More than three centuries after philosopher John Locke observed that ideas sometimes drift through the mind unbidden—a phenomenon the French called “reverie”—modern psychologists are reconsidering the value of moments when the mind wanders freely. In an era dominated by constant phone use, researchers warn that such mental meandering, often dismissed as distraction, may actually serve important cognitive functions.

A recent review by Shivang Shelat and Jonathan Schooler of the University of California, Santa Barbara, examined over a decade of research on mind wandering, defined as when one’s thoughts disengage from the immediate environment. Although traditionally viewed as a lapse in attention, accumulating evidence suggests that this state often contributes to key mental processes.

One notable benefit involves memory consolidation. Studies indicate that allowing thoughts to roam can reinforce recently acquired information as the mind revisits it during periods of idle reflection. Additionally, mind wandering may enhance “statistical learning,” the brain’s capacity to detect patterns amid complex data streams. For example, a music enthusiast listening to an unfamiliar melody may become better at anticipating its progression during spontaneous mental wandering.

This research challenges the prevailing wellness narrative that idealizes constant present-moment awareness. In some cases, disengaging from focused thought can prevent unnecessary mental exertion. An experiment asking participants to select a poster demonstrated that those instructed to let their minds wander arrived at choices with satisfaction comparable to those who deliberately weighed their options, but with less cognitive effort.

However, Shelat cautions that mind wandering is not universally beneficial. Complex or consequential decisions—such as choosing a mortgage or a political leader—likely require active deliberation. Moreover, mind wandering can sometimes impair performance, especially if it interferes with tasks requiring attention or leads to negative rumination that exacerbates emotional distress.

According to Shelat, the timing and context of mind wandering are crucial. It tends to be most advantageous when it occurs voluntarily and during low-stakes moments, such as while walking. Yet, modern lifestyles may restrict these opportunities. Shelat argues that pervasive smartphone use has supplanted many chances for constructive mental wandering, as people frequently shift rapidly between apps in search of constant stimulation.

“To benefit from mind wandering, we need to relearn how to be bored and to engage in deep, unstructured thought,” Shelat said. He suggests that reducing screen time could help restore these valuable brain states, allowing the mind space to explore, consolidate information, and foster creativity.