Understanding sources of adult age differences in task switching: Evidence from behavioral and ERP studies

The task-switching paradigm is a valid tool to measure age-related changes in executive functions. It allows identifying the most vulnerable cognitive control processes affected by aging. This review provides an overview about the current evidence on behavioral and electrophysiological signatures of adult age differences in task switching with a focus on age-related changes in ERP correlates of three task-processing phases: (1) advanced task preparation as reflected by the cue-P3 and the CNV; (2) task implementation including P1 / N1, P2, N2, N450 / Ni as well as target-P3; and (3) response monitoring mechanisms as indicated by the Nc / CRN / MFN during correct responding and Ne / ERN in error trials. While most of these ERP correlates of executive control are reduced in older age, qualitative ERP differences between age groups are less consistent. We also report some recent findings from cognitive training research showing the potential for enhancement in task switching in older age. The results are discussed in the light of current models of cognitive control