Electrical stimulation of excitable cells-a model approach

The authors provide an introduction to the study of the quantitative response of excitable cells to stimulating currents through the use of mathematical models. Considered is the behavior of a spherical cell in a uniform field and a circular fiber in a point source field, where, for simplicity, only steady-state solutions are included. In each case a characteristic length is associated with the cell and governs the nature of its response. Some work is presented on the response of a fiber bundle to a point-source stimulus. Here, too, a characteristic length is found to be important. In this case, the steady-state behavior of a particular fiber depends on the location of that fiber within the bundle. It is concluded that these results should be useful in the initial design of electrodes for functional electrical simulation