Human Cognitive Aging: Maintenance Versus Dedifferentiation

Human cognitive aging differs between and is malleable within individuals. In the absence of a strong genetic program, it is open to a host of hazards, such as vascular and metabolic risk, but also open to protective and enhancing factors, such as experience-dependent cognitive plasticity. Longitudinal studies suggest that leading an intellectually challenging, physically active, and socially engaged life might mitigate losses and consolidate gains, but results need to be interpreted with caution, as individuals are not randomly assigned to lifestyles. In this presentation, I will report on (i) the degree to which individual differences in cognitive decline generalize across abilities; (ii) the role education in adult cognitive development; (iii) the search for domain-general causes of cognitive aging that reduce the distinctiveness of representations and processing pathways (i.e., dedifferentiation); (iv) brain maintenance as a potential mechanism for mitigating dedifferentiation and cognitive decline.