School of Physics Nonlinear Science & Mathematical Physics: Prof. Plamen Ch. Ivanov, Boston University

Physiological systems under neural regulation exhibit erratic fluctuations, which traditionally have been considered as noise and thus, often neglected. However, recent findings indicate that physiologic dynamics are characterized by temporal scale-invariant structures spanning time scales from seconds to hours, nonlinear forms of phase synchronization and self-organized criticality type behavior resembling nonequilibrium physical systems. We will briefly review fundamental concepts in modern physics, and we will demonstrate their usefulness in studying cardiac dynamics, cardio-respiratory coupling and sleep across different physiologic states and conditions.