Evidence for the sparing of reactive cognitive control with age.

The dual mechanisms of control account posited two qualitatively different cognitive control mechanisms (Braver, Gray, & Burgess, 2007). Proactive control is a sustained and capacity-demanding mechanism that is used to prevent interference, whereas reactive control acts transiently, poststimulus onset, to resolve interference. Prior research has demonstrated age-related deficits in proactive control, including in conflict tasks. However, few studies have examined the putative sparing of reactive control with age, and the purpose of this study was to fill that gap. In Experiment 1, older adults, like young adults, showed less interference for mostly incongruent items than mostly congruent items in a picture-word Stroop task, and this pattern extended to novel, 50% congruent transfer items. In Experiment 2, flanker stimuli in one screen location (or color) were mostly congruent whereas flanker stimuli in a second location (or color) were mostly incongruent. Young and older adults demonstrated context-specific proportion congruence effects, showing less interference in the mostly incongruent as compared to mostly congruent context for the location cue but not the color cue. These findings provide converging evidence for the intact and flexible use of reactive control with age, and challenge the view that aging is associated with a general deficit in cognitive control.