Dual-axis myelination covariance drives the functional connectivity emergence during infancy

Area of Science:

• Neuroscience
• Developmental Neuroscience
• Brain Imaging

Background:

• Perinatal brain functional connectivity mechanisms are not fully understood.
• Existing models emphasize white matter myelination, yet neonates show mature networks with immature white matter.

Purpose of the Study:

• To propose gray matter myelination covariance as a basis for early functional connectivity.
• To introduce a dual-axis myelination covariance framework and a myelination-function coupling (MFC) index for newborns.

Main Methods:

• Development of a dual-axis myelination covariance framework.
• Derivation of a novel myelination-function coupling (MFC) index for the neonatal brain.
• Analysis of spatial patterns, age-dependency, and correlation with gene expression.

Main Results:

• The MFC index revealed distinct spatial patterns in sensory and motor cortices.
• MFC strength increased with age and showed distance-dependent properties.
• Neonatal MFC patterns correlated with gene expression related to neurovascular coupling and predicted later behaviors.

Conclusions:

• Early brain functional integration relies on both white matter and intracortical microstructure synchrony.
• Gray matter myelination covariance is a critical factor in the emergence of neonatal functional networks.
• The findings provide a new framework for understanding the developmental connectome in infancy.