Having or losing a family physician: a protocol for a survey-based study of patient's continuity of primary care experience in Quebec, Canada.

As people live longer, there is growing interest in identifying everyday behaviors and activities that support cognitive functioning across the lifespan (). Rather than viewing cognitive aging as an inevitable decline, research highlights the capacity of the aging brain to remain adaptive and responsive to lifestyle influences well into later life (). Leisure activities are activities people engage in discretionary time, free of work and other obligations (; ). Commonly categorized as physical, social, cognitive, and passive activities, effects of leisure activities on cognitive functioning have been primarily examined in older populations who are at heightened risk of cognitive decline (; ). Physical, social, and cognitive activities refer to activities that are actively engaging in terms of physical functioning (e.g., exercises), social engagement (meeting with friends), and mental stimulation (reading, internet), while passive activities are characterized by low levels of physical, social, and cognitive engagement (e.g., watching TV, napping) (; ; ). Leisure activities are associated with older adults’ cognitive functioning in cross-sectional studies and at follow-up waves in long-term longitudinal studies (; ). These findings are promising because they suggest that individuals can proactively shape their cognitive trajectories, by allocating their time and effort to certain leisure activities (). However, most studies have focused on aggregate measures of activity engagement (e.g., frequency) over extended periods (), limiting the understanding of the fine-grained processes through which specific activity episodes shape cognitive functioning in daily life (; ). Emerging research using ambulatory assessment designs (i.e., involving repeated measurements of activities and cognition in participants’ natural environments) offers a higher-resolution view. Notably, leisure activities may produce short-term “boosts” in cognitive performance over hours. For example, two recent studies reported that single bouts of leisure activity had a time-lagged association with improved numerical working memory in middle-aged and older adults (; ). These findings are important elements toward developing evidence-based behavioral guidelines and interventions (; ). Yet, more research is needed to understand the short-term dynamics between leisure activity and other cognitive domains beyond numerical working memory. In cognitive aging research, the “use it or lose it” hypothesis posits that engagement in cognitive, social, and physical activities protects older adults from age-related cognitive decline (; ). That is, the “use it or lose it” hypothesis recommends continuously engaging in cognitively enriching activities or else the protective effects from activities will wane (Hertzog, 2009). In support of this hypothesis, longitudinal studies showed that physical (e.g., walking), social (e.g., meeting with friends), and cognitive activities (e.g., reading) were associated with better subsequent cognitive abilities after years, whereas passive activities (e.g., watching TV) were associated with worse subsequent cognitive abilities (; ; ). Similarly, the cognitive reserve hypothesis posits that leisure activities contribute to building up cognitive reserve, the accumulation of which can help resist cognitive decline (). This hypothesis emphasizes that reserve accumulation is a long-term process, necessitating a decent amount of activity engagement over a long time (). Yet both theories focus on long-term outcomes, leaving open the question of how single bouts of leisure activity may influence cognitive performance on more immediate timescales.