https://doi.org/10.1140/epjb/e2013-40422-7
Regular Article
Frequency enhancement in coupled noisy excitable elements: effects of network topology
1 Department of Physics, Graduate Institute of Biophysics, and Center for Complex Systems, National Central University, Chungli, Taiwan 320, P.R. China
2 Institute of Physics, Academia Sinica, Nankang, Taipei, Taiwan 115, P.R. China
a
e-mail: pylai@phy.ncu.edu.tw
Received: 21 April 2013
Received in final form: 13 May 2013
Published online: 22 July 2013
Coupled excitable elements in the presence of noise can exhibit oscillatory behavior with non-trivial frequency dependence as the coupling strength of the system increases. The phenomenon of frequency enhancement (FE) occurs in some coupling regime, in which the elements can oscillate with a frequency higher than their uncoupled frequencies. In this paper, details of the FE are investigated by simulations of the FitzHugh-Nagumo model with different network topologies. It is found that the characteristics of FE, such as the maximal enhancement coupling, enhancement level etc, are functions of the network topology and spatial dimensions. The effect of excitability and the spatio-temporal patterns during FE are investigated to provide an intuitive picture for the enhancement mechanism. Interestingly, some of these characteristics of FE can be described by scaling laws; suggesting the existence of universality in the FE phenomenon. The relevance of these results to biological rhythms are also discussed.
Key words: Statistical and Nonlinear Physics
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag, 2013