Pulse Dynamics in Coupled Excitable FIbers: Soliton-like Collision,   Recombination, and Overtaking
  We study the dynamics of a reaction-diffusion system composed of two mutually coupled excitable fibers. We focus on the situation in which dynamical properties of the two fibers are not identical because of the parameter difference between the fibers. Using the spatially one-dimensional FitzHugh-Nagumo equations as a model of a single excitable fiber, we show that the system exhibits a rich variety of dynamical behavior, including soliton-like collision between two pulses, recombination of a solitary pulse and synchronized pulses, and overtaking of a slow-moving solitary pulse by fast-moving synchronized pulses. 
Hiromichi Suetani, Tatsuo Yanagita, and Kazuyuki Aihara