A framework for quantifying node-level community structure group differences in brain connectivity networks

Med Image Comput Comput Assist Interv. 2012;15(Pt 2):196-203. doi: 10.1007/978-3-642-33418-4_25.

Abstract

We propose a framework for quantifying node-level community structures between groups using anatomical brain networks derived from DTI-tractography. To construct communities, we computed hierarchical binary trees by maximizing two metrics: the well-known modularity metric (Q), and a novel metric that measures the difference between inter-community and intra-community path lengths. Changes in community structures on the nodal level were assessed between generated trees and a statistical framework was developed to detect local differences between two groups of community structures. We applied this framework to a sample of 42 subjects with major depression and 47 healthy controls. Results showed that several nodes (including the bilateral precuneus, which have been linked to self-awareness) within the default mode network exhibited significant differences between groups. These findings are consistent with those reported in previous literature, suggesting a higher degree of ruminative self-reflections in depression.

MeSH terms

  • Algorithms*
  • Brain / anatomy & histology*
  • Connectome / methods*
  • Diffusion Tensor Imaging / methods*
  • Female
  • Humans
  • Image Enhancement / methods
  • Image Interpretation, Computer-Assisted / methods*
  • Imaging, Three-Dimensional / methods*
  • Male
  • Middle Aged
  • Nerve Net / anatomy & histology*
  • Reproducibility of Results
  • Sensitivity and Specificity