Longitudinal Study of Adolescent Brain Connectivity Development Using Sign-Aware Graph Theory Metrics

Area of Science:

• Neuroscience
• Developmental Neuroscience
• Network Science

Background:

• Adolescence involves significant brain network reorganization impacting cognitive and behavioral development.
• The sensorimotor-association (SA) axis is a proposed framework for functional connectivity development.
• Previous studies often use cross-sectional data and treat positive and negative connections equally.

Purpose of the Study:

• To investigate longitudinal changes in adolescent brain functional connectivity using resting-state fMRI.
• To compare network development using absolute-value versus sign-aware graph-theoretical approaches.
• To examine the influence of positive and negative connections on developmental gradients.

Main Methods:

• Analysis of longitudinal resting-state fMRI data from 125 adolescents (ages 12-18, 3 time points).
• Application of functional connectivity strength and graph-theoretical metrics.
• Comparison of absolute-value networks (ignoring connection sign) versus sign-aware networks.

Main Results:

• Positive connections showed age-related changes along the SA axis (r=-0.614, p<0.001), particularly in sensorimotor regions.
• Negative connections did not align with the SA axis (r=0.031, p=0.803).
• Graph-theoretical measures yielded opposing developmental gradients based on network construction (absolute-value vs. positive-only).

Conclusions:

• Developmental inferences in the adolescent brain are highly dependent on the treatment of negative connections and network topology.
• The study challenges the concept of a single organizational gradient in brain development.
• Sign-aware graph-theoretical approaches are crucial for accurately understanding adolescent brain maturation.