Is a wandering mind a sign of aging?

Mind wandering occupies an essential part of our awakened life and concerns all spontaneous thoughts unrelated to an ongoing activity. Laboratory research has studied this mental state during the execution of specific tasks measuring the conditions of emergence, the frequency and content of spontaneous thoughts and the consequences, usually harmful, on the performances tested. This mini review aims to define the phenomenon, expose the prejudices on performance and the assets of the wandering mind, and present the literature on the effects of cognitive aging on the incidence and characteristics of mind wandering. Various studies have shown a reduction in task-unrelated thoughts in the elderly, combined with an increase in task-related interfering thoughts. Some explanations are proposed, such as reducing cognitive resources or increasing motivation in the context of normal aging. The content of mind wandering seems crucial to understanding how this phenomenon evolves in aging. Hence, in future research, an assessment of the characteristics of the thoughts (emotion, temporality, association with stimuli, etc.) will deepen our knowledge of the link between mind wandering and aging.