title: Keeping it steady: older adults perform more consistently on cognitive tasks than younger adults.
abstract: People often attribute poor performance to having bad days. Given that cognitive aging leads to lower average levels of performance and more moment-to-moment variability, one might expect that older adults should show greater day-to-day variability and be more likely to experience bad days than younger adults. However, both researchers and ordinary people typically sample only one performance per day for a given activity. Hence, the empirical basis for concluding that cognitive performance does substantially vary from day to day is inadequate. On the basis of data from 101 younger and 103 older adults who completed nine cognitive tasks in 100 daily sessions, we show that the contributions of systematic day-to-day variability to overall observed variability are reliable but small. Thus, the impression of good versus bad days is largely due to performance fluctuations at faster timescales. Despite having lower average levels of performance, older adults showed more consistent levels of performance across days.
authors.affiliation: 1Center for Lifespan Psychology, Max Planck Institute for Human Development, Berlin, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Schmiedek
authors.forename: Martin
authors.initials: M
authors.lastname: Lövdén
authors.forename: Ulman
authors.initials: U
authors.lastname: Lindenberger
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000523:psychology*; D003071:Cognition / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology; D011930:Reaction Time / Q000502:physiology; D013647:Task Performance and Analysis; D055815:Young Adult
keywords: adult development; aging; cognitive development; cognitive performance; daily fluctuations; normal aging; within-person variability