White matter microstructure and macrostructure brain charts across the human lifespan

Area of Science:

• Neuroscience
• Medical Imaging
• Developmental Biology

Background:

• Normative reference charts are crucial for assessing development by comparing individual traits to population data.
• Existing charts cover brain gray matter but lack a framework for white matter (WM), essential for neural communication.
• White matter's microstructural and macrostructural evolution across the lifespan remains uncharacterized by normative data.

Purpose of the Study:

• To create the first comprehensive white matter brain charts for normative reference across the lifespan.
• To characterize the age- and sex-stratified trajectories of white matter microstructural and macrostructural features.
• To establish a foundational metric for neuroscience research and clinical applications by providing interpretable WM reference data.

Main Methods:

• Leveraged a large dataset of 26,199 diffusion MRI scans from 42 harmonized studies.
• Employed generalized additive models for location, scale, and shape (GAMLSS) for trajectory estimation.
• Estimated age- and sex-stratified normative trajectories for 72 individual white matter pathways.

Main Results:

• Developed comprehensive white matter brain charts detailing microstructural and macrostructural features across the lifespan.
• Quantified normative trajectories for 72 distinct white matter pathways, revealing maturation and decline patterns.
• Demonstrated applications in identifying developmental milestones, detecting clinical deviations, and enabling standardized centile scoring.

Conclusions:

• The presented white matter brain charts offer a unified, interpretable reference framework for brain structure.
• These charts are foundational for research and clinical neuroscience, facilitating precise mapping of WM development, aging, and pathology.
• Open-access tools and methods are provided to support cross-study analysis and application in diverse populations.