STOCHASTIC FEEDBACK AND THE REGULATION OF BIOLOGICAL RHYTHMS

We propose a general approach to the question of how biological rhythm s spontaneously self-regulate, based on the concept of ''stochastic fe edback''. We illustrate this approach by considering at a coarse-grain ed level the neuroautonomic regulation of the heart rate. The model ge nerates complex dynamics and successfully accounts for key characteris tics of cardiac variability, including the 1/f power spectrum, the fun ctional form and scaling of the distribution of variations, and correl ations in the Fourier phases indicating nonlinear dynamics.