Dataset Information

High-resolution multi-shot diffusion imaging of structural networks in healthy neurocognitive aging.

ABSTRACT: Healthy neurocognitive aging has been associated with the microstructural degradation of white matter pathways that connect distributed gray matter regions, assessed by diffusion-weighted imaging (DWI). However, the relatively low spatial resolution of standard DWI has limited the examination of age-related differences in the properties of smaller, tightly curved white matter fibers, as well as the relatively more complex microstructure of gray matter. Here, we capitalize on high-resolution multi-shot DWI, which allows spatial resolutions < 1 mm³ to be achieved on clinical 3T MRI scanners. We assessed whether traditional diffusion tensor-based measures of gray matter microstructure and graph theoretical measures of white matter structural connectivity assessed by standard (1.5 mm³ voxels, 3.375 μl volume) and high-resolution (1 mm³ voxels, 1μl volume) DWI were differentially related to age and cognitive performance in 61 healthy adults 18-78 years of age. Cognitive performance was assessed using an extensive battery comprising 12 separate tests of fluid (speed-dependent) cognition. Results indicated that the high-resolution data had larger correlations between age and gray matter mean diffusivity, but smaller correlations between age and structural connectivity. Moreover, parallel mediation models including both standard and high-resolution measures revealed that only the high-resolution measures mediated age-related differences in fluid cognition. These results lay the groundwork for future studies planning to apply high-resolution DWI methodology to further assess the mechanisms of both healthy aging and cognitive impairment.

SUBMITTER: Merenstein JL

PROVIDER: S-EPMC10482115 | biostudies-literature | 2023 Jul

REPOSITORIES: biostudies-literature

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High-resolution multi-shot diffusion imaging of structural networks in healthy neurocognitive aging.

Merenstein Jenna L JL Zhao Jiayi J Mullin Hollie A HA Rudolph Marc D MD Song Allen W AW Madden David J DJ

NeuroImage 20230525

Healthy neurocognitive aging has been associated with the microstructural degradation of white matter pathways that connect distributed gray matter regions, assessed by diffusion-weighted imaging (DWI). However, the relatively low spatial resolution of standard DWI has limited the examination of age-related differences in the properties of smaller, tightly curved white matter fibers, as well as the relatively more complex microstructure of gray matter. Here, we capitalize on high-resolution mult ...[more]

PMID: 37244322

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Dataset Information

High-resolution multi-shot diffusion imaging of structural networks in healthy neurocognitive aging.

Publications

High-resolution multi-shot diffusion imaging of structural networks in healthy neurocognitive aging.

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