The effect of aging on high level cognitive functions is still relatively misunderstood. The aim of this research is to better understand individual performance differences between young and elderly individuals, by studying the attentional control processes involved in task switching. Initially, two switching tasks were administered to young and elderly adults. The results indicate no age effect on the switching cost but show an asymmetric switching cost (Study 1) and different local and global switching costs between individuals (study 1 and 2). In a second step, a computational cognitive modeling of cognitive functioning is built using the ACT-R architecture. It enables to test the veracity of the assumptions of reduced processing speed (PS) and reduced capacity of working memory (WMC), to reproduce the observed performance differences between young and old individuals. The results of the hypothesis tests for both studies indicate that these assumptions do not reproduce adequately the empirically observed effects, which implies that the assumptions of decreased PS or WMC are insufficient to explain the individual performance differences observed. This study highlights the interest of computational cognitive modeling in the understanding of the processes underlying human cognitive functioning.
