Activate index: an integrated index to reveal disrupted brain network organizations of major depressive disorder patients

TL;DR

This study introduces the 'active index', a new metric combining rich club and diverse club concepts, to analyze brain network disruptions in MDD patients, revealing insights into brain functional organization.

Contribution

The paper proposes the novel 'active index' for brain network analysis, demonstrating its effectiveness in distinguishing MDD patients from healthy controls.

Findings

Active index outperforms existing metrics in MDD analysis.

Rich and diverse club metrics are complementary in brain network studies.

Active index reveals new aspects of brain functional integration in MDD.

Abstract

Altered functional brain networks have been a typical manifestation that distinguishes major depressive disorder (MDD) patients from healthy control (HC) subjects in functional magnetic resonance imaging (fMRI) studies. Recently, rich club and diverse club metrics have been proposed for network or network neuroscience analyses. The rich club defines a set of nodes that tend to be the hubs of specific communities, and the diverse club defines the nodes that span more communities and have edges diversely distributed across different communities. Considering the heterogeneity of rich clubs and diverse clubs, combining them and on the basis to derive a novel indicator may reveal new evidence of brain functional integration and separation, which might provide new insights into MDD. This study for the first time discussed the differences between MDD and HC using both rich club and diverse club metrics and found the complementarity of them in analyzing brain networks. Besides, a novel index, termed "active index", has been proposed in this study. The active index defines a group of nodes that tend to be diversely distributed across communities while avoiding being a hub of a community. Experimental results demonstrate the superiority of active index in analyzing MDD brain mechanisms.