Learning is not just a process of acquiring knowledge; it’s a fundamental aspect of human development with profound implications for brain health, mental wellbeing, and societal progress. Continuous learning fosters resilience, cognitive flexibility, and problem-solving abilities, vital for managing stress and promoting emotional wellbeing. It empowers individuals to develop self-confidence, competence, and mastery over challenges, enhancing self-esteem and overall mental health. Moreover, learning fuels critical thinking, creativity, and innovation, driving societal advancement and cultural evolution. Brain plasticity, the brain’s ability to adapt and change throughout life, underpins learning and cognitive development. Structural and functional changes in the brain occur in response to learning experiences, highlighting the importance of cognitive stimulation in maintaining brain health and cognitive function. Lifelong learning builds cognitive reserve, a reservoir of cognitive capacity that buffers against age-related cognitive decline and neurological disorders. Engaging in diverse, intellectually stimulating activities enhances cognitive reserve, underscoring the lifelong value of education and mental stimulation in preserving brain health and cognitive function.

Participation in activities that provide opportunities for mental, physical, or social engagement have been supported as cognitively protective in later life. Theories propose how mentally stimulating activities might improve or maintain specific cognitive abilities across the life course or reduce age-related cognitive changes, for example, while physical activities might promote brain health via a reduction in cardiovascular risk profiles. Given that such lifestyles and behaviors are potentially modifiable, positive associations between activity participation and maintained cognitive abilities in old age highlight leisure-time pursuits as targets for intervention. However, associations between activity participation and cognitive aging may be prone to reverse causation: those with higher engagement across the life course might have always had higher levels of cognitive ability. Life course approaches are therefore needed to correctly identify the potentially beneficial effects of activity participation. In addition, given the growth and development of cognitive abilities across the life span, there may be specific types of activity or engagement that are beneficial at different points. Understanding the associations between mental, physical, and social activity participation and cognitive aging supports the development of interventions against age-related cognitive decline, ranging from targeted cognitive training programs to broader engagement-based approaches. An ultimate goal of research exploring activity participation and cognitive aging is to provide clear and accurate information to individuals regarding the steps they might take to promote brain health in later life.