  Trapping and un-trapping of spiral tips in a two-dimensional homogeneous
excitable medium with local small-world connections is studied by numerical
simulation. In a homogeneous medium which can be simulated with a lattice of
regular neighborhood connections, the spiral wave is in the meandering regime.
When changing the topology of a small region from regular connections to
small-world connections, the tip of a spiral waves is attracted by the
small-world region, where the average path length declines with the
introduction of long distant connections. The "trapped" phenomenon also occurs
in regular lattices where the diffusion coefficient of the small region is
increased. The above results can be explained by the eikonal equation and the
relation between core radius and diffusion coefficient.
