Mathematical Biology Seminar: Frequency Variation and Waves in Coupled Excitable Systems

  • Date: 02/09/2010
Pik-Yin Lai (National Central University, Taiwan)

University of British Columbia


Two topics will covered in this talk. The first part concerns the
dynamics of coupled excitable FitzHugh-Nagumo elements in the presence
of noise, which is used to model the frequency variations in beating
cardiac cultures. As the coupling strength increases, the frequency
increases with a peak which is associated with the synchronization of
the elements. The physical mechanism of frequency enhancement is due to
the variation of the potential barrier for firing as the coupling
changes and can be estimated by Kramer's escape rate theory which shows
good agreement with simulations. The second part is about waves in
phase coupled excitable medium. The corresponding phase diagrams for
stable plane waves and spiral waves are obtained by simulations. This
discrete model corresponds to an excitable medium with
zero-refractoriness and in the continuum limit supports zero-core
spiral waves.


2:00pm - 3:00pm, WMAX 110.