The relationships between cardiorespiratory fitness, white matter integrity, and cognitive function in older adulthood
Year: 2015
Type: article
Study design: Observational Study
Abstract: White matter in the brain supports higher-order cognitive processes by facilitating signal transmission between diverse cortical regions. White matter integrity declines with advancing age, leading to impairments in memory and executive processes in older adulthood. Recent research suggests that higher-fit older adults may be less susceptible to white matter degeneration, although evidence for this relationship is limited. Here we examine whether cardiorespiratory fitness correlates with white matter integrity and whether this relationship further predicts cognitive performance in a large, older adult sample. Diffusion tensor imaging was used to determine microstructural white matter integrity in a group of 113 (mean age = 66.61) neurologically healthy adults. Measures of cardiorespiratory fitness (VO2), working memory, and executive function were also collected. Using a whole-brain voxelwise analysis, we found that higher fitness levels predicted greater white matter integrity in multiple fiber pathways. We explored this relationship further using a region of interest approach, and found that higher fitness was associated with greater microstructural integrity in the anterior internal capsule and corona radiata, which contain fibers that project from subcortical to prefrontal structures. Further, statistical mediation analysis revealed that white matter integrity within the anterior internal capsule and corona radiata mediated the relationship between fitness and spatial working memory performance. Results suggest that higher levels of aerobic fitness may protect against age-related declines in white matter integrity, which may, in turn, preserve memory performance in older adulthood.
Author: Lauren E. Oberlin
Language: English
Subfield: Radiology, Nuclear Medicine and Imaging
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W945014665