What the Stroop, Simon, and Flanker tasks reveal on the neurocognitive changes related to ageing and Alzheimer’s disease?

Interference tasks such as the Simon, Flanker, and Stroop tasks have largely been used to investigate cognitive processing, with an emphasis on executive control processes such as the ability to inhibit irrelevant information (i.e., inhibition) and disengage attention from the previous trial (i.e., attentional switching). In the present study, we aim to examine the theoretical issues concerning changes in speed of processing, executive control processes, and modified brain activity patterns underlying physiological ageing, mild cognitive impairment (MCI) and Alzheimer’s disease (AD). To this end, we will carry out a meta-analysis of studies that used the mentioned interference tasks and that tested cognitive changes in healthy older adults as well as in older adults with MCI and AD. In addition, we will review the neurophysiological findings obtained by means of electroencephalogram (EEG), event-related brain potentials (ERP), and functional magnetic resonance imaging (fMRI) to shed light on several theoretical issues concerning changes in speed of processing, inhibitory control, and modified brain activity patterns underlying physiological ageing and AD. We conclude by discussing to what extent the results of the present study provide support for neurocognitive theories explaining cognitive and neural changes associated with physiological ageing, MCI, and AD.