White matter differences between younger and older adults revealed by fixel-based analysis

Area of Science:

• Neuroscience
• Gerontology
• Radiology

Background:

• Healthy aging involves neural structure alterations, impacting cognitive and motor functions.
• White matter (WM) changes are significant in aging.
• Conventional neuroimaging methods have limitations in capturing complex WM geometry.

Purpose of the Study:

• Investigate whole-brain WM differences between young and old individuals.
• Utilize a novel technique, fixel-based analysis (FBA), for WM assessment.
• Characterize complex WM changes and their link to cognitive abilities in healthy aging.

Main Methods:

• Study involved 120 healthy volunteers.
• Employed fixel-based analysis (FBA) for whole-brain WM analysis.
• Assessed age-related differences in WM tracts and their correlation with cognitive performance and risk factors.

Main Results:

• Older adults exhibited reduced FBA-derived metrics in several WM tracts, notably in frontal areas.
• Age-related WM differences did not correlate significantly with alcohol consumption, exercise frequency, or pulse pressure.
• FBA-derived WM measures predicted cognitive performance in older adults.

Conclusions:

• FBA is a potent technique for characterizing complex WM changes associated with aging.
• WM alterations are linked to cognitive abilities in healthy aging.
• Comprehensive assessments integrating neuroimaging, cognitive evaluation, and demographics are crucial for understanding healthy aging.