The human organism is an integrated network where complex physiological systems, each with its own regulatory mechanisms, continuously interact, and where failure of one system can trigger a breakdown of the entire network. Identifying and quantifying dynamical networks of diverse systems with different types of interactions is a challenge. Here we develop a framework to probe interactions among diverse systems, and we identify a physiological network. We find that each physiological state is characterized by a specific network structure, demonstrating a robust interplay between network topology and function. Across physiological states, the network undergoes topological transitions associated with fast reorganization of physiological interactions on time scales of a few minutes, indicating high network flexibility in response to perturbations. The proposed system-wide integrative approach may facilitate the development of a new field, Network Physiology.
Bibliographical noteFunding Information:
We thank T. Penzel for providing the data and helpful comments, and A.Y. Schumann for help with data selection, data pre-processing and discussions. We acknowledge support from NIH Grant 1R01-HL098437, the US-Israel Binational Science Foundation (BSF Grant 2008137), the Office of Naval Research (ONR Grant 000141010078), the Israel Science Foundation, the European Community (projects DAPHNet/FP6 IST 018474-2 and SOCIONICAL/FP7 ICT 231288) and the Brigham and Women’s Hospital Biomedical Research Institute Fund. R.P.B. acknowledges support from the German Academic Exchange Service (DAAD fellowship within the Postdoc-Programme).