I strongly recommend the following article, "Mapping the Structural Core of the Human Cerebral Cortext" by Patric Hagmann et al…
Here's an excerpt:
"Structurally segregated and functionally specialized regions of the human
cerebral cortex are interconnected by a dense network of cortico-cortical
axonal pathways. By using diffusion spectrum imaging, we noninvasively mapped
these pathways within and across cortical hemispheres in individual human
participants. An analysis of the resulting large-scale structural brain
networks reveals a structural core within posterior medial and parietal
cerebral cortex, as well as several distinct temporal and frontal modules.
Brain regions within the structural core share high degree, strength, and
betweenness centrality, and they constitute connector hubs that link all major
structural modules. The structural core contains brain regions that form the
posterior components of the human default network. Looking both within and
outside of core regions, we observed a substantial correspondence between
structural connectivity and resting-state functional connectivity measured in
the same participants. The spatial and topological centrality of the core
within cortex suggests an important role in functional integration."
Core centrality and arborescence… sound familiar?
Sorry for the quality of the image. Best to consult the article online!