Functional Geometry of Human Connectome and Robustness of Gender Differences

TL;DR

This study explores the higher-order geometric structure of human brain networks, revealing gender-related differences in connectome complexity and connectivity patterns using advanced topological methods.

Contribution

It introduces a novel simplicial complex approach to analyze higher-order brain network relationships and compares the functional geometry between male and female connectomes.

Findings

Common F extbackslash&M-connectome shares hyperbolic geometry with M-connectome.

F-connectome exhibits additional connections, larger simplexes, and new cycles.

Gender differences influence the complexity and organization of brain network structures.

Abstract

Mapping the brain imaging data to networks, where each node represents a specific area of the brain, has enabled an objective graph-theoretic analysis of human connectome. However, the latent structure on higher-order connections remains unexplored, where many brain regions acting in synergy perform complex functions. Here we analyse this hidden structure using the simplicial complexes parametrisation where the shared faces of simplexes encode higher-order relationships between groups of nodes and emerging hyperbolic geometry. Based on data collected within the Human Connectome Project, we perform a systematic analysis of consensus networks of 100 female (F-connectome) and 100 male (M-connectome) subjects by varying the number of fibres launched. Our analysis reveals that the functional geometry of the common F\&M-connectome coincides with the M-connectome and is characterized by a complex architecture of simplexes to the 14th order, which is built in six anatomical communities, and short cycles among them. Furthermore, the F-connectome has additional connections that involve different brain regions, thereby increasing the size of simplexes and introducing new cycles. By providing new insights into the internal organisation of anatomical brain modules as well as into the links between them that are essential to dynamics, these results also highlight the functional gender-related differences