Effects of aging and valence on emotional response inhibition: conclusions from a novel stop-signal task

Emotional and cognitive processes interact in myriad ways during daily life, and the relation between emotion and cognition changes across the lifespan. Aging is associated with decreasing cognitive control and inhibition alongside improvements in emotional control and regulation. However, little is known about how aging impacts response inhibition within emotionally relevant contexts. The current study examined how aging impacts emotional response inhibition by comparing older and younger adults' ability to stop responses to emotional images. Participants completed a novel stop-signal task where pleasant and unpleasant scene images appeared on a minority of trials, while participants developed a pre-potent 'go' response during trials presenting neutral shapes. Notably, in each task block only one of the two types of emotional scene images served as a task-relevant stop cue, e.g., unpleasant images as stop-signals. Accordingly, in a given task block participants should continue to respond at the onset of the other type of emotional image (i.e., pleasant scenes as 'go-images'). Overall, older adults exhibited less efficient stopping than younger adults. However, stopping did not differ between pleasant and unpleasant images in either age group. Thus, while response inhibition is less efficient in older adults, it does not differ by emotion across adulthood. The innovative design also permitted exploratory analyses of responses to images that were not the current stop-signal, i.e., responses correctly executed for 'go-image' trials. In contrast with response inhibition on stop trials, emotion and aging significantly interacted during response execution, with older adults performing less accurately than younger adults on unpleasant go-image trials. Taken together, aging interacts with emotion only for response execution but not response inhibition for emotional scenes. This study offers new insights into the effects of aging on response inhibition in emotionally complex contexts and increases the ecological validity of response inhibition research. It also highlights the distinct effects of aging and emotion on response execution versus inhibition for task-relevant emotional information.