Heterogeneity in cognitive maturation and aging: Why there is no such thing as an adult control
24.17, Saturday, May 11, 2:30 - 4:15 pm, Royal Ballroom 1-3
Laura Germine1,2,3, Joshua Hartshorne4, Jeremy Wilmer5, Christopher Chabris6, Garga Chatterjee4, Ken Nakayama1; 1Psychology Department, Harvard University, 2Psychiatry Department, Massachusetts General Hospital, 3Center for Human Genetic Research, Massachusetts General Hospital, 4Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, 5Psychology Department, Wellesley College, 6Department of Psychology, Union College
Research on cognitive change typically focuses on early development or aging, and thus we have little knowledge of cognitive changes that might occur in adulthood. Taking advantage of large Web-based samples, we previously showed that both face learning ability and approximate number sense peak relatively late in adulthood (after age 30), whereas recognition memory for inverted faces and memory for names peak much earlier (Germine et al., 2011; Halberda et al., 2012). Here, we expand on these findings by examining cognitive change over the lifespan across a wide range of cognitive abilities. First, we present results from a systematic analysis of published data from the Wechsler Adult Intelligence Scales and Wechsler Memory Scales showing that there is wide variation in the ages of peak performance on standardized IQ and memory tests. Second, we present findings from year-by-year analysis of large web samples on tests of processing speed, verbal and visual recognition memory, verbal and visual working memory, complex emotion perception, and crystallized verbal intelligence (sample sizes ranging from 3,000 to 10,000 for each test). Again, we find substantial heterogeneity in the peaks of different cognitive functions across the age range. While some cognitive abilities peak very early, declining after age 20 (e.g. processing speed), other cognitive abilities do not peak until around age 40 (e.g. complex emotion perception). Our findings also add to the growing list of cognitive functions that peak around age 30, including verbal and visual domains of working memory. Our data support the notion that changes in cognitive function over the lifespan are impacted by age-related change in multiple, dissociable factors. Finally, our data suggest that there is no age at which an adult has reached peak for all major cognitive functions.