title: Mechanism of spiral formation in heterogeneous discretized excitable media.
abstract: Spiral waves on excitable media strongly influence the functions of living systems in both a positive and negative way. The spiral formation mechanism has thus been one of the major themes in the field of reaction-diffusion systems. Although the widely believed origin of spiral waves is the interaction of traveling waves, the heterogeneity of an excitable medium has recently been suggested as a probable cause. We suggest one possible origin of spiral waves using a Belousov-Zhabotinsky reaction and a discretized FitzHugh-Nagumo model. The heterogeneity of the reaction field is shown to stochastically generate unidirectional sites, which can induce spiral waves. Furthermore, we found that the spiral wave vanished with only a small reduction in the excitability of the reaction field. These results reveal a gentle approach for controlling the appearance of a spiral wave on an excitable medium.
authors.affiliation: Meiji Institute for Advanced Study of Mathematical Sciences (MIMS), 4-21-1 Nakano, Tokyo 164-8525, Japan.
authors.forename: Shu-ichi
authors.initials: S
authors.lastname: Kinoshita
authors.forename: Mayuko
authors.initials: M
authors.lastname: Iwamoto
authors.forename: Keita
authors.initials: K
authors.lastname: Tateishi
authors.forename: Nobuhiko J
authors.initials: NJ
authors.lastname: Suematsu
authors.forename: Daishin
authors.initials: D
authors.lastname: Ueyama
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000818:Animals; D016477:Artifacts; D001683:Biological Clocks; D003198:Computer Simulation; D006801:Humans; D008959:Models, Neurological; D009415:Nerve Net / Q000502:physiology*; D009431:Neural Conduction / Q000502:physiology*