The modelling of the modes of propagation of SD waves in brain structures taking into account the nonuniform density of the active elements

: Character of spreading depression (SD) wave propagation was studied on two-dimensional model of excitable tissue. It was shown that strips with diminished density of active elements were of different permeability for the waves depending on their front orientation and curvature. When triggered near the border with a rarefied strip the wave could not penetrate through it and the effect of wave "sliding" along this strip was observed. In several-compartment model imitating the diffusely connected cortico-striatal system of the rat brain the sequence of events was determined by a primary focus position. In this model a single stimulus could provoke not only one wave but re-entry waves and reverberators. Described mechanism of repetitive waves generation in inhomogeneous tissue allow to interpret unusual SD wave consequences observed in electrophysiological experiments.