Controlled movement and suppression of spiral waves in excitable media

Here we propose mechanisms for controlling the movement and suppression of spiral waves in discrete excitable media. We show that the controlled drift and subsequent annihilation of a spiral wave can be achieved through the c ombination of two factors: the introduction of small spatial inhomogeneitie s in the medium and the interaction of the wave with the boundaries of the medium. The inhomogeneities can be introduced in the spatial distribution o f the relaxation parameters or in the coupling coefficient of the slow vari ables of the partial cells making up the medium. [S1063-651X(98)00912-X].