Coexisting forms of coupling and Phase-Transitions in physiological networks

Abstract

Utilizing methods from nonlinear dynamics and a network approach we investigate the interactions between physiologic organ systems. We demonstrate that these systems can exhibit multiple forms of coupling that are independent from each other and act on different time scales. We also find that physiologic systems interaction is of transient nature with intermittent “on” and “off” periods, and that different forms of coupling can simultaneously coexist representing different aspects of physiologic regulation. We investigate the network of physiologic interactions between the brain, cardiac and respiratory systems across different sleep stages, well-defined physiologic states with distinct neuroautonomic regulation, and we uncover a strong relationship between network connectivity, patterns in network links strength and physiologic function. We show that physiologic networks exhibit pronounced phase transitions associated with reorganization in network structure and links strength in response to transitions across physiologic states.