Acquisition of Cognitive Data

Data were collected for comprehensive medical, physiological, and neuropsychological evaluations approximately every 2 years and since 2000 every year for participants older than 80 years. We selected six cognitive tests that have previously been shown to be sensitive to individual differences in primarily memory (Golski et al., 1998; Balthazar et al., 2008; Goh et al., 2012) or both memory and executive function (Paula et al., 2013; Shao et al., 2014) during healthy cognitive aging. These tests included the Boston Naming Test (BNT), the Benton Visual Retention Test (BVRT), California Verbal Learning Test (CVLT), the Clock Drawing Test (CLOCKs), the Category and Letter Fluency Tests. The data used in our analysis was acquired for the BVRT between 1960 and 2014, for the CVLT between 1993 and 2014, and for the remaining three tests between 1984 and 2014. Until 2005 the CLOCKs and Fluency Tests were only obtained from participants with age ≥60 years instead of at every visit. The specific measures used from each cognitive test, the range for each measure and a summary of the cognitive processes contributing to each measure are shown in Supplementary Table S2.