Mapping the Structural Core of Human Cerebral Cortex

TLDR

Structurally segregated and functionally specialized regions of the human cerebral cortex are interconnected by a dense network of cortico‑cortical axonal pathways. Using diffusion spectrum imaging, we noninvasively mapped these pathways within and across cortical hemispheres in individual human participants. The analysis revealed a structural core in posterior medial and parietal cortex, comprising high‑centrality connector hubs that link distinct temporal, frontal, and default‑network modules, and showed strong correspondence between structural and resting‑state functional connectivity, underscoring the core’s role in cortical integration.

Abstract

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.