Spatiotemporal stochastic resonance in excitable media.

Pattern formation far from equilibrium has been studied very extensively in the last years (for a recent review, see [1,2]). Representative examples are Rayleigh-Benard convection rolls, Taylor-Couette flow, and spiral waves in the Belousov-Zhabotinsky reaction. Typically a pattern starts to build up when the control parameter (the temperature difference in case of the Rayleigh-Benard system) becomes larger than a critical value. Noise makes the bifurcation smooth by triggering the onset of the pattern even below threshold r , rc. The role of fluctuations for the onset and selection of patterns has been studied in some detail and is reported on in a number of articles in [3,4] and [5]. In this paper, we discuss the role of noise for the formation of patterns in two-dimensional excitable media from a different perspective. It has been shown that a certain amount of noise can amplify temporal patterns by increasing the system’s sen