Format

Send to

Choose Destination
See comment in PubMed Commons below
Neuroimage. 2016 May 1;131:91-101. doi: 10.1016/j.neuroimage.2015.09.053. Epub 2015 Oct 9.

White matter microstructure mediates the relationship between cardiorespiratory fitness and spatial working memory in older adults.

Author information

  • 1Department of Psychology, University of Pittsburgh, USA; Center for the Neural Basis of Cognition, University of Pittsburgh, USA. Electronic address: leo11@pitt.edu.
  • 2Center for the Neural Basis of Cognition, University of Pittsburgh, USA; Department of Psychology, Carnegie Mellon University, USA.
  • 3Department of Human Development and Family Studies, Colorado State University - Fort Collins, USA; Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, USA.
  • 4Department of Psychological and Brain Sciences, University of Iowa, USA.
  • 5Department of Psychology, Ohio State University, USA.
  • 6Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, USA.
  • 7Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, USA.
  • 8Department of Kinesiology, Wayne State University, USA.
  • 9Department of Preventative Medicine, Northwestern University, USA.
  • 10Department of Kinesiology, Kansas State University, USA.
  • 11Harvard Medical School, USA.
  • 12Exercise Science Department, Bellarmine University, USA.
  • 13Department of Psychology, University of Pittsburgh, USA; Center for the Neural Basis of Cognition, University of Pittsburgh, USA.

Abstract

White matter structure declines with advancing age and has been associated with a decline in memory and executive processes in older adulthood. Yet, recent research suggests that higher physical activity and fitness levels may be associated with less white matter degeneration in late life, although the tract-specificity of this relationship is not well understood. In addition, these prior studies infrequently associate measures of white matter microstructure to cognitive outcomes, so the behavioral importance of higher levels of white matter microstructural organization with greater fitness levels remains a matter of speculation. Here we tested whether cardiorespiratory fitness (VO2max) levels were associated with white matter microstructure and whether this relationship constituted an indirect pathway between cardiorespiratory fitness and spatial working memory in two large, cognitively and neurologically healthy older adult samples. Diffusion tensor imaging was used to determine white matter microstructure in two separate groups: Experiment 1, N=113 (mean age=66.61) and Experiment 2, N=154 (mean age=65.66). Using a voxel-based regression approach, we found that higher VO2max was associated with higher fractional anisotropy (FA), a measure of white matter microstructure, in a diverse network of white matter tracts, including the anterior corona radiata, anterior internal capsule, fornix, cingulum, and corpus callosum (PFDR-corrected<.05). This effect was consistent across both samples even after controlling for age, gender, and education. Further, a statistical mediation analysis revealed that white matter microstructure within these regions, among others, constituted a significant indirect path between VO2max and spatial working memory performance. These results suggest that greater aerobic fitness levels are associated with higher levels of white matter microstructural organization, which may, in turn, preserve spatial memory performance in older adulthood.

KEYWORDS:

Aging; Fitness; Memory; White matter

PMID:
26439513
PMCID:
PMC4826637
[Available on 2017-05-01]
DOI:
10.1016/j.neuroimage.2015.09.053
[PubMed - in process]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Support Center