Autowave Processes , Nerve Pulse Propagation , and Heart Activity

Abstract

The main property of nerve cells is their ability to conduct nerve pulses—electrical waves spreading along the nerve fiber. The conduction property is based on the fact that the elementary volume of a membrane is a local active element possessing the ability to amplify an incoming electrical signal. Nerve pulse propagation is one of the most striking examples of autowave processes in living systems. In the middle of the nineteenth century it was found that nerve pulses in frogs spread without visible damping over rather large distances, up to 10 cm (Helmholtz 1850). German scientist Hermann Ludwig Ferdinand von Helmholtz (1821–1894) was the first scientist to measure the speed of excitation spread in a nerve—in experiments on frogs in 1850, and in 1867–1870 together with Russian scientist Nikolai Bakst—in a human being and determined the conditions of the threshold electrical stimulation of nerve fibers. Helmholtz also made the first experimental attempt to determine the rhythm of pulses sent by the brain to muscles and determined the period of muscle response to sensory irritation.