The effects of emotion on executive functions in ageing

Abstract

Executive functions are control mechanisms that allow us to direct thoughts and behaviour according to goals and play an important role in everyday life. Research suggests that emotion can affect these functions, but it is less clear how the emotion-cognition interactions change with age, as ageing is associated with changes in both emotional and cognitive functioning. The aim of the present research was to investigate the effects of emotion on younger and older adults’ performance in tasks targeting three executive functions: updating, inhibition and task switching. It was also investigated whether emotional valence, the task relevance of emotion and the modality of emotional items (e.g., verbal or facial material) played a role in the modulating effect of emotion on cognition. Across nine behavioural experiments, the following main results were observed. First, it was found that age modulated the effects of emotional valence on executive functions. More specifically, positive emotion improved cognitive performance in both age groups, whereas the mixed but predominantly impairing effects of negative emotion were more pronounced in older adults. Second, emotion affected executive functions when it was task-relevant and older adults were not more affected by task-irrelevant emotional material than younger adults. Third, effects observed for emotional faces could not be replicated with emotional words and the effects of emotion varied for different executive functions, suggesting that the effects of emotion are modality- and task-specific. This dissertation highlights that theories aimed at explaining the effects of emotion on executive functions need to be extended to accommodate age-related differences in this interaction. A better understanding of the facilitating and impairing effects of emotion on executive functions in ageing is important, as it can help identifying areas in which emotion buffers age-related cognitive decline