Impulse Propagation

Abstract

If a cell of approximately spherical shape is placed in a stimulating electric field, the induced transmembrane potential will be the same over the entire membrane. If this potential is transthreshold, the entire cell will be excited synchronously and a membrane action potential results. On the other hand, for a long thin fiber the initial depolarized region, using a pair of closely spaced electrodes, has a limited extent; in this case, propagation from the active to adjoining inactive regions will take place. Since the topic of this chapter is propagation we will consider the latter configuration.