Young participants data supporting for "An investigation into semantic cognition in the ageing brain"

This pre-registered fMRI study investigated the nature of age-related neural activation changes within the domain of semantic cognition. We used functional magnetic resonance imaging (fMRI) to examine the neural activity patterns of classic semantic regions and large-scale brain networks and their relationships with task demands. We found that both left and right inferior frontal gyri (IFG) exhibited a linear activation-demand relationship across age groups and semantic tasks, indicating the left IFG as a main semantic area accompanied with a compensation-related recruitment of the right IFG for increasing semantic demands. However, a similar effect was not replicated in anterior temporal regions (ATL). At network-level, we found that aligning with older people’s greater reserves of prior knowledge and declined executive control ability, the senior brain exhibited a greater engagement of the default mode network (DMN) and less of the executive multiple demand network (MDN). Older adults also showed a degraded ability in modulating the activation of MDN as a function of demand in the non-semantic task (but not in the semantic tasks), whereas this ability was preserved in the network contributing specifically for semantic control (SCN). No age-related changes in network coupling were found in the current dataset. These findings depict a comprehensive picture of how the brain adapts in older age, and the factors we found may account for the preserved performance of older people in the semantic domain.