Stochastic sensitivity analysis of noise-induced transitions in a biochemical model with birhythmicity

A mathematical model of the biochemical reaction with nonlinear recycling of the product into substrate is considered. The main control parameter of this model is the substrate injection rate, which is subject to random disturbances. We study noise-induced oscillations in the parameter zones where the system is bistable and exhibit a coexistence of the equilibrium and limit cycle, or two stable cycles (birhythmicity). Phenomena of the generation of noisy birhythmicity and 'stochastic preference' of attractors are studied on the basis of the stochastic sensitivity function technique, confidence domains method, and statistics of interspike intervals. (paper)