Within node connectivity changes, not simply edge changes, influence graph theory measures in functional connectivity
Wenjing Luo1, Abigail S Greene2, R Todd Constable3
1Biomedical Engineering, Yale University School of Medicine, United States.
Neuroimage
|July 5, 2021
Summary
Brain connectivity studies using graph theory are impacted by how nodes are defined. Reconfiguring nodes, not just fixed ones, significantly alter network-level findings, revealing crucial brain state changes.
Area of Science:
- Neuroscience
- Network Science
- Computational Biology
Background:
- Graph theory is widely applied to functional connectivity studies in the brain.
- Functional brain nodes are known to reconfigure with changing brain states.
- Previous studies have predominantly used fixed nodes for graph theory analysis.
Purpose of the Study:
- To investigate the impact of different node parcellation strategies on brain functional connectivity findings.
- To determine if considering dynamic node reconfigurations influences network-level analysis outcomes.
- To highlight the importance of voxel-level changes in node definition for graph theory studies.
Main Methods:
- Utilized fixed, group, state-specific, and individualized parcellations to define graph nodes.
- Analyzed functional connectivity data across different brain states and groups.
- Compared network-level findings based on static versus dynamic node definitions.
Main Results:
- Functional connectivity changes within nodes significantly influence network-level findings.
- Some previously reported state- or group-dependent changes were not observed when considering node reconfigurations.
- Network changes were only apparent when voxel-level node reconfigurations were accounted for.
Conclusions:
- Graph theory analyses of brain connectivity should incorporate dynamic node reconfigurations.
- Voxel-level changes impacting node definition are critical for accurate network analysis.
- The choice of node parcellation significantly affects the interpretation of functional brain organization.


