Age affects the adjustment of cognitive control after a conflict: evidence from the bivalency effect.

Age affects cognitive control. When facing a conflict, older adults are less able to activate goal-relevant information and inhibit irrelevant information. However, cognitive control also affects the events after a conflict. The purpose of this study was to determine whether age affects the adjustment of cognitive control following a conflict. To this end, we investigated the bivalency effect, that is, the performance slowing occurring after the conflict induced by bivalent stimuli (i.e., stimuli with features for two tasks). In two experiments, we tested young adults (aged 20-30) and older adults (aged 65-85) in a paradigm requiring alternations between three tasks, with bivalent stimuli occasionally occurring on one task. The young adults showed a slowing for all trials following bivalent stimuli. This indicates a widespread and long-lasting bivalency effect, replicating previous findings. In contrast, the older adults showed a more specific and shorter-lived slowing. Thus, age affects the adjustment of cognitive control following a conflict.