Keeping Busy May Also Keep Dementia at Bay by Improving Cognitive Skills
A somewhat hectic schedule might protect a person from cognitive decline, a study from the University of Texas at Dallas reported. Busy people had better processing speed, working memory, episodic memory, and reasoning and language skills independent of age and education, indicating that a busy lifestyle might boost neuronal connections.
Busy lifestyles — a hallmark of our time — are frequently associated with negative health outcomes, but few studies have looked into the relationship between keeping busy and cognitive health.
The study,“The Busier the Better: Greater Busyness Is Associated with Better Cognition,” explored engagement levels and cognition, and how they vary with age in 330 individuals enrolled in the Dallas Lifespan Brain Study (DLBS). The participants, ages 50 to 89, were assessed on five cognitive constructs — processing speed, working memory, episodic memory, reasoning, and crystallized knowledge, which measures vocabulary. They also completed a questionnaire about their levels of activity.
Demographic data revealed that younger participants tended to be more busy than older ones. Likewise, women were more busy than men, as were people with higher education levels.
Busier people also had faster processing speed, better working and episodic memory, as well as better reasoning and vocabulary.  An older age did not impact the relationship, since analyses showed the association was similar across the age range investigated. Taking both age and education into account, the study, published in the journal Frontiers in Aging Neuroscience, also revealed that keeping busy was the main determinant of cognition, particularly episodic memory.
As with all correlational studies, there is no way to know how activity levels and cognition are linked. Engagement might boost cognition, but it might also be true that individuals who  perform better cognitively are capable of engaging in more activities. But other studies have indicated that an active lifestyle, of which busyness might be considered a proxy, delays cognitive decline and protects against dementia.
Nevertheless, the study suggested a number of mechanisms by which activity might promote cognition. As busyness is likely to promote opportunities for learning, and learning is known to slow the loss of neurons in the brain’s memory headquarters — the hippocampus — busyness might contribute to the maintenance of these neurons.
Some studies also suggest that new neural pathways might be formed as a consequence of engagements present in a busy life. Yet others hypothesize that busyness promotes the development of a cognitive reserve — the encouragement of better cognitive strategies — or expanded processing resources, often referred to as the brain reserve.
According to what is known as the environmental complexity hypothesis, busy people might also encounter more complex situations, find they need to take more complex decisions or solve difficult or ill-defined problems — stimuli that scientists believe promote cognition. Busy people also tend to rely more on memory strategies and aids that may improve performance.
Whether any of these mechanisms are involved in building the link between a busy lifestyle and cognition remains to be established in prospective studies following participants over time. Until then, keeping yourself busy is likely a safe bet that will, at least, not reduce those cognitive abilities.