Aging Cognitive Control and Inhibition: Parallel or Joint Processes?

Working memory is fundamental to cognitive control, maintaining and updating information to adjust behaviors. Age-related deficits in working memory may account for the shift from proactive control (young adults; YA) towards reactive control (older adults; OA). The inhibitory deficit hypothesis suggests that age-related decline in cognitive inhibition, a filtering mechanism of goal-irrelevant information, may account for these deficits. However, little is known about the role of cognitive inhibition in cognitive control. We tested 83 OA and 75 YA on a modified cognitive control task: goal-irrelevant information (distractors) was introduced during interstimulus delays. OA responded faster to congruent trials (i.e., distractors matching cues) compared to incongruent or neutral trials, whereas this effect was absent in YA. OA showed a slightly higher proactive control tendency than YA. Although the results are partially consistent with an age-associated inhibitory deficit, no clear evidence was found for the role of cognitive inhibition in cognitive control.