Figure 3.

Evidence for a shift in the brain-derived neurotrophic factor genotype-phenotype association in executive function over a 10-year span in older adults. Participants in this study performed a switching task, a common measure of executive function twice over a 10-year period. There were two conditions: a repeat condition in which two tasks of the same type follow each other and switch conditions when the tasks switch from one trial to the next. There was a main effect of condition such that all participants were slower on the switch condition than repeat. Although Val/Val carriers performed faster at time 1, they were the only group to show a decline in performance over a 10-year span (data adapted from Erickson and others 2008).