Microstructural Features Linking White Matter and Mathematics in Adolescence

Area of Science:

• Neuroscience
• Developmental Neuroscience
• Neuroimaging

Background:

• Mathematics relies on coordinated brain networks, but the specific white matter microstructural features involved are not fully understood.
• Diffusion Tensor Imaging (DTI) has identified white matter tracts supporting math, yet lacks specificity in microstructural detail.
• Advanced Magnetic Resonance Imaging (MRI) methods offer more precise insights into white matter microstructure.

Purpose of the Study:

• To investigate the relationship between specific white matter microstructural features and mathematical abilities in children.
• To utilize advanced MRI techniques beyond DTI to probe axon packing, fiber orientation, and myelin content.
• To examine both cross-sectional and longitudinal associations between white matter microstructure and math skills.

Main Methods:

• Applied DTI alongside advanced MRI techniques (NODDI, ihMT, mcDESPOT, g-ratio imaging) in a longitudinal cohort of 33 children (ages 6-16).
• Analyzed partial correlations between white matter microstructure metrics and math skill in specific white matter tracts (superior/inferior longitudinal fasciculi, corticospinal tract, splenium).
• Controlled for age and gender in cross-sectional and longitudinal analyses.

Main Results:

• Cross-sectionally, fiber coherence in the corticospinal tract and superior longitudinal fasciculus correlated with math performance.
• Longitudinally, changes in axonal packing and myelin markers were associated with changes in math skill and fluency.
• Myelin-sensitive metrics showed the most prevalent links, with decreased myelin correlating with improved math skills over time.

Conclusions:

• White matter microstructure, especially myelin, plays a regionally specific role in mathematical abilities during development.
• Longitudinal findings suggest ongoing refinement of the neural networks supporting mathematics, potentially involving myelin adjustments.
• While preliminary and not surviving multiple comparisons, these results offer valuable insights for future research on brain-math relationships.