Summary: Computer Physics Communications 121­122 (1999) 126­128
www.elsevier.nl/locate/cpc
Modeling heart rate variability by stochastic feedback
Luís A. Nunes Amaral a,1, Ary L. Goldberger b, Plamen Ch. Ivanov c, H. Eugene Stanley c
a Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
b Cardiovascular Division, Harvard Medical School, Boston, MA 02215, USA
c Centre for Polymer Studies and Department of Physics, Boston University, Boston, MA 02215, USA
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. © 1999 Published by Elsevier Science B.V. All rights reserved.
The principle of homeostasis asserts that biological
systems seek to maintain a constant output after
perturbation [1]. Recent evidence, however, indicates
that healthy systems display highly irregular dynamics
with complex fluctuations [2]. A particularly striking
example is heart rate variability [3­6]. Contrary to
what we would naively expect [7], the human heart

Source: Amaral, Luis A.N. - Department of Chemical and Biological Engineering, Northwestern University
Stanley, H. Eugene - Department of Physics, Boston University

Collections: Biology and Medicine; Computer Technologies and Information Sciences; Materials Science; Physics