The neural substrates of enhanced response Inhibition induced by attentional capture in older adults with a higher moderate-to-vigorous physical activity: a VBM and resting-state functional connectivity study.

Abstract

Response inhibition is more sensitive to aging than other forms of inhibitory control. Mounting evidence suggests that moderate-to-vigorous physical activity (MVPA) can promote response inhibition and age-related brain structure and function in the frontal cortex. Nevertheless, a limitation of existing work is that it primarily focuses on the direct influence of MVPA on response inhibition, without directly examining how MVPA affects the component task processes that are involved in response inhibition. ActiGraph GT3X+ accelerometers were employed to quantify MVPA and to categorize older adults aged 60-79 years old into a higher physical activity group (HG) and a lower physical activity group (LG). The participants in the two groups completed three novel versions of the stop-signal task (SST), and structural as well as resting-state functional magnetic resonance images were collected. First, the behavioural data showed that the participants in the HG exhibited superior performance in inhibitory and attentional control than those in the LG. Second, the voxel-based morphometry (VBM) analysis revealed that the grey matter volume (GMV) in the right inferior frontal gyrus (rIFG) and the left superior frontal gyrus (lSFG) differed between the two groups. Third, the resting-state functional connectivity (rsFC) analysis with the rIFG, lSFG or right pre-supplementary motor area (rpre-SMA) as a seed region revealed that the participants in the HG had a greater functional connectivity (rsFC) than the LG. Finally, partial correlation analysis indicated that the GMV and the rsFC could jointly account for group differences in response inhibition and attentional control induced by MVPA. (1) MVPA is positively associated with response inhibition in older adults, and the positive relationship is associated with effective attentional resource allocation for faster attentional capture; and (2) distinct frontal subregions of the brain induced by MVPA participate in different cognitive processes involved in response inhibition; particularly, the benefit from rIFG enhancement may be realized through optimizing attentional capture.