Cognition across the lifespan: Aging and gender differences

Maintaining cognitive health across the lifespan has been the focus of a multi-billion-dollar industry. In order to guide treatment and interventions, a clear understanding of the way that proficiency in different cognitive domains develops and declines across the lifespan is necessary. Additionally, there are gender differences in a range of other factors, such as anxiety and substance use, that are also known to affect cognition, although the scale of this interaction is unknown. Our objective was to assess differences in cognitive function across the lifespan in men and women in a large, representative sample. Over 45,000 individuals were tested on 12 cognitive tasks. Segmented regression was used to model the trajectory of three cognitive domains: short-term memory, verbal abilities, and reasoning. Each domain showed a unique trajectory, suggesting that not all cognitive abilities develop and decline in the same way. Gender differences were found in all three domains; however, after controlling for socio-demographic factors, these differences were greatly reduced or disappeared. These results suggest that the trajectory of cognition across the lifespan differs for men and women, but is greatly influenced by environmental factors. We discuss these findings within a framework that describes gender differences in cognition as likely guided by a complex interplay between biology and environment.