Lifetime enhancement of scroll rings by spatiotemporal fluctuations

The dynamics of three-dimensional scroll rings with spatiotemporal random e xcitability is investigated numerically using the FitzHugh-Nagumo model. De pending on the correlation time and length scales of the fluctuations, the lifetime of the ring filament is enlarged and a resonance effect between th e time scale of the scroll ring and the time correlation of the noise is ob served. Numerical results are interpreted in terms of a simplified stochast ic model derived from the kinematical equations for three-dimensional excit able waves.