Modeling heart rate variability by stochastic feedback

Amaral, L. A.; Goldberger, A. L.; Stanley, H. E.

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NASA NTRS · 20040088956

Modeling heart rate variability by stochastic feedback

Amaral, L. A.·Goldberger, A. L.·Stanley, H. E.

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Abstract

We consider the question of how the cardiac rhythm spontaneously self-regulates and propose a new mechanism as a possible answer. We model the neuroautonomic regulation of the heart rate as a stochastic feedback system and find that the model successfully accounts for key characteristics of cardiac variability, including the 1/f power spectrum, the functional form and scaling of the distribution of variations of the interbeat intervals, and the correlations in the Fourier phases which indicate nonlinear dynamics.

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Non-NASA Center NASA Discipline Cardiopulmonary Nonlinear Dynamics Heart Rate/physiology Stochastic Processes Models, Cardiovascular Human Sympathetic Nervous System/physiology Heart/innervation Parasympathetic Nervous System/physiology Sinoatrial Node/physiology

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Amaral, L. A., Goldberger, A. L., Stanley, H. E.. 1999-01-01. Modeling heart rate variability by stochastic feedback. https://ntrs.nasa.gov/citations/20040088956

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