Network Analysis of Brain Structure and Function

The human brain is a complex network of neurons whose dynamic patterns of electrical activity give rise to our rich conscious experience. How do the white matter pathways in our brain facilitate correlated brain activity between various brain regions? Using a network science approach, we seek to elucidate this relationship between brain structure and function. Networks are defined as brain regions (nodes) with their connectivity inferred from DTI and rsfMRI data to derive structural and functional brain networks respectively. We uncover fundamentally different hierarchical, modular organisations in brain structure and function. The structural network is spatially constrained with an apparent core comprising midbrain structures, while the functional network is a diffuse network with many cross-hemispheric long-range connections. Both networks show high levels of clustering with the presence of varying community structures and rich/diverse clubs. Interestingly, a non-small-world structural network appears to enable a small-world functional network, yielding more food for thought about the reciprocal relationship between brain structure and function.