Robust probabilistic measurement of structural-functional module consistency in infant brain development

Area of Science:

• Neuroimaging
• Network Neuroscience
• Developmental Neuroscience

Background:

• Brain networks are typically segmented into modules to analyze segregated functional roles in group-level neuroimaging studies.
• Assessing structural-functional consistency across individuals presents challenges due to varying module sizes and inter-individual variability.

Purpose of the Study:

• To introduce a novel method for robust probabilistic measurement of structural-functional module consistency (SFMC) in brain networks.
• To evaluate the consistency between structural and functional brain modules while accounting for population size differences and inter-individual variability.
• To compare the novel stochastic module approach with conventional methods for assessing structural-functional coupling.

Main Methods:

• Development of stochastic modules, representing the probability of a brain region's assignment to a group-level sub-network across subjects.
• Application of the stochastic module method to assess SFMC in a group of subjects.
• Comparison of SFMC trends with conventional structural-functional coupling approaches.

Main Results:

• The stochastic module method robustly evaluates SFMC, accommodating differing module population sizes and inter-individual variability.
• A more pronounced decline in structural-functional coupling was observed using the stochastic module method compared to conventional approaches, suggesting significant developmental reorganization.
• Analysis of Baby Connectome Project (BCP) data revealed that SFMC decreases from 0 to 5 years old.
• SFMC was found to be higher in primary brain regions (e.g., visual areas) and lower in advanced cognitive regions (e.g., attention, control, default mode network).

Conclusions:

• Stochastic modules provide a robust probabilistic framework for measuring structural-functional module consistency in brain networks.
• The novel method highlights significant developmental reorganization and a decline in structural-functional coupling during early childhood.
• Findings indicate differential developmental trajectories of structural-functional integration across brain regions, with primary areas showing higher consistency than advanced cognitive networks.