Regional Superficial White Matter Macrostructural and Microstructural Changes Across the Lifespan

Motivation: Superficial white matter (SWM) comprises a majority of total brain white matter. However, there is currently no clear classification for SWM and its changes across the lifespan have been underexplored. Goal(s): We propose lobe-specific analyses of SWM to characterize how regional SWM macrostructure and microstructure change across the lifespan. Approach: Leveraging large-scale neuroimaging data (2380 healthy participants, 5-100 years old), we applied advanced quantitative diffusion tractography to track lobe-specific SWM. Results: There are differential trajectories in SWM macrostructure and microstructure spatially across brain lobes and temporally across the lifespan, with the greatest changes occurring during development. Impact: This study characterizes typical lobe-specific changes in SWM integrity and structure across the lifespan. The normative trajectories of macrostructural and microstructural properties further lay a foundation for future research to investigate atypical changes in SWM in neurologic disease.