When I'm 64: Age-related variability in over 40,000 online cognitive test takers.
Annalise A LaPlumeNicole D AndersonLarissa McKettonBrian LevineAngela K TroyerPublished in: The journals of gerontology. Series B, Psychological sciences and social sciences (2021)
Lifespan cognitive performance shows a non-linear pattern, with gradual decline over early and mid-adulthood, followed by a transition in the sixties to notably accelerated, but more variable, decline. Some people show less decline than others, and some cognitive abilities show less within-person decline than others.