Tracking Age-Related Topological Changes in Individual Brain Morphological Networks Across the Human Lifespan

Area of Science:

• Neuroscience
• Network Science
• Developmental Biology

Background:

• Population-based studies reveal age-related topological alterations in brain morphological networks.
• Individual-level changes in brain networks across the lifespan remain less understood.

Purpose of the Study:

• To characterize age-related topological changes in individual brain networks throughout the lifespan.
• To investigate the relationship between individual and group brain network structures at nodal, modular, and connectome levels.

Main Methods:

• Retrospective analysis of T1-weighted MPRAGE MRI scans from 179 healthy individuals (aged 6-85 years).
• Calculation of nodal (similarity, matching), modular (modularity, AMI), and connectome (efficiency, path length) indicators.
• Regression models were used to analyze lifespan trajectory patterns of network attributes.

Main Results:

• 34 out of 68 nodes showed significant age-related patterns in nodal similarity, with linear and quadratic trends.
• Connectome-level attributes displayed U-shaped or inverse U-shaped lifespan trajectories.
• Average nodal similarity between individual and group networks was 0.67, and average Adjusted Mutual Information (AMI) for module partitions was 0.57.

Conclusions:

• Lifespan trajectories of nodal similarity primarily followed linear decreasing and nonlinear trends.
• Modularity and global topological attributes exhibited nonlinear age-related patterns.
• High consistency was observed between individual and group brain network analyses in terms of nodal similarity and modular division.