Dwelling Quietly in the Rich Club: Brain Network Determinants of Slow Cortical Fluctuations

TL;DR

This study investigates how the brain's rich club network influences slow cortical fluctuations, revealing a core that stabilizes internal states and surrounding regions that support rapid perception, with implications for psychiatric disorders.

Contribution

It demonstrates the role of the rich club in maintaining slow, stable brain activity and highlights the interaction between structural topology and functional dynamics.

Findings

Rich club regions promote stable, slow fluctuations in brain activity.

Surrounding cortical regions exhibit rapid, unstable dynamics.

Implications for understanding mood, anxiety, and psychiatric disorders.

Abstract

For more than a century, cerebral cartography has been driven by investigations of structural and morphological properties of the brain across spatial scales and the temporal/functional phenomena that emerge from these underlying features. The next era of brain mapping will be driven by studies that consider both of these components of brain organization simultaneously -- elucidating their interactions and dependencies. Using this guiding principle, we explored the origin of slowly fluctuating patterns of synchronization within the topological core of brain regions known as the rich club, implicated in the regulation of mood and introspection. We find that a constellation of densely interconnected regions that constitute the rich club (including the anterior insula, amygdala, and precuneus) play a central role in promoting a stable, dynamical core of spontaneous activity in the primate cortex. The slow time scales are well matched to the regulation of internal visceral states, corresponding to the somatic correlates of mood and anxiety. In contrast, the topology of the surrounding "feeder" cortical regions show unstable, rapidly fluctuating dynamics likely crucial for fast perceptual processes. We discuss these findings in relation to psychiatric disorders and the future of connectomics.