Cross-Population White Matter Atlas Creation for Concurrent Mapping of Brain Connections in Neonates and Adults with Diffusion MRI Tractography

2025-12-23

AI Summary

Existing white matter (WM) atlases are limited to single populations—either adults or neonates—and lack spatial harmonization, impeding cross-population comparisons. This study introduces the first unified neonatal–adult brain atlas (NABA) of WM connectivity, enabling direct intergroup comparison and developmental analysis using diffusion MRI tractography data. Methodologically, we establish the first lifespan-spanning spatial normalization framework; develop a robust, data-driven fiber clustering algorithm to accommodate large-scale anatomical variability; and integrate fractional anisotropy (FA) quantification with multidimensional group-level modeling (accounting for age, sex, and preterm birth). Key findings include: (1) 23 core WM tracts shared between neonates and adults; (2) rapid FA maturation in long-range association fibers; (3) earlier FA development in female versus male neonates; and (4) compensatory FA elevation in preterm infants within specific tracts—including the corticospinal tract.

Technology Category

• Cognitive Modeling & Cognitive Systems: Adaptive Behavior
• Natural Language Processing: Lexical Semantics and Morphology
• Humans and AI: Brain-Sensing and Analysis

Application Category

• Web Mining and Content Analysis: Large pretrained models with web data
• Graph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphs
• Social Networks and Social Media: Fairness and bias in social network and social media analysis

Abstract

Comparing white matter (WM) connections between adults and neonates using diffusion MRI (dMRI) can advance our understanding of typical brain development and potential biomarkers for neurological disorders. However, existing WM atlases are population-specific (adult or neonatal) and reside in separate spaces, preventing direct cross-population comparisons. A unified WM atlas spanning both neonates and adults is still lacking. In this study, we propose a neonatal/adult brain atlas (NABA), a WM tractography atlas built from dMRI data of both neonates and adults. NABA is constructed using a robust, data-driven fiber clustering pipeline, enabling group-wise WM atlasing across populations despite substantial anatomical variability. The atlas provides a standardized template for WM parcellation, allowing direct comparison of WM tracts between neonates and adults. Using NABA, we conduct four analyses: (1) evaluating the feasibility of joint WM mapping across populations, (2) characterizing WM development across neonatal ages relative to adults, (3) assessing sex-related differences in neonatal WM development, and (4) examining the effects of preterm birth. Our results show that NABA robustly identifies WM tracts in both populations. We observe rapid fractional anisotropy (FA) development in long-range association tracts, including the arcuate fasciculus and superior longitudinal fasciculus II, whereas intra-cerebellar tracts develop more slowly. Neonatal females exhibit faster overall FA development than males. Although preterm neonates show lower overall FA development rates, they demonstrate relatively higher FA growth in specific tracts, including the corticospinal tract, corona radiata-pontine pathway, and intracerebellar tracts. These findings demonstrate that NABA is a useful tool for investigating WM development across neonates and adults.

Problem

• Creating a unified white matter atlas for neonates and adults
• Enabling direct comparison of brain connections across different age groups
• Investigating white matter development and differences in neurological conditions

Innovation

• Unified neonatal-adult white matter atlas creation
• Data-driven fiber clustering for cross-population atlasing
• Standardized template enabling direct tract comparison