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arXiv · 2503.14700

From Density to Void: Why Brain Networks Fail to Reveal Complex Higher-Order Structures

Moo K. Chung·Anass B. El-Yaagoubi·Anqi Qiu·Hernando Ombao
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Abstract

In brain network analysis using resting-state fMRI, there is growing interest in modeling higher-order interactions beyond simple pairwise connectivity via persistent homology. Despite the promise of these advanced topological tools, robust and consistently observed higher-order interactions over time remain elusive. In this study, we investigate why conventional analyses often fail to reveal complex higher-order structures - such as interactions involving four or more nodes - and explore whether such interactions truly exist in functional brain networks. We utilize a simplicial complex framework often used in persistent homology to address this question.

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Moo K. Chung, Anass B. El-Yaagoubi, Anqi Qiu, Hernando Ombao. 2025-03-18. From Density to Void: Why Brain Networks Fail to Reveal Complex Higher-Order Structures. https://arxiv.org/abs/2503.14700

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