The effect of vascular health factors on white matter microstructure mediates age-related differences in executive function performance

摘要: Even within healthy aging, vascular risk factors can detrimentally influence cognition, with executive functions (EF) particularly vulnerable. Fronto-parietal white matter (WM) connectivity in part, supports EF and may be sensitive to risk. Here, we utilized structural equation modeling 184 adults (aged 20-94 years of age) test the hypotheses that: 1) fronto-parietal WM microstructure mediates age effects on EF; 2) higher blood pressure (BP) hyperintensity (WMH) burden influences this association. All participants underwent comprehensive cognitive neuropsychological testing including tests processing speed, function (with a focus tasks that require switching inhibition) completed an MRI scanning session included FLAIR imaging for semi-automated quantification diffusion-weighted tractography. Structural models were specified (as continuous variable) predicting within-tract WMH fractional anisotropy speed. Results indicated genu corpus collosum, superior longitudinal fasciculus, inferior frontal occipital fasciculus mediated association between EF. Additionally, increased systolic these tracts contribute worsening health are important underlying age-brain-behavior associations. These findings suggest aging brings about increases both BP burden, which involved degradation turn, negatively impact as age.