ABSTRACT
A breakthrough in our understanding of the physics of neural signals, which propagate as membrane voltage along a nerve fiber (axon), was achieved by the ingenious work of Hodgkin and Huxley
on the nonmyelinated squid axon. This work helped explain the action potential or “spike” that conveys the all-or-none response of neurons. To explore the complicated gating mechanism of the ion channels, the stimulating electrode was a long uninsulated wire, thus every part of the neural membrane had to react in the same way; that is, propagation of signals was prevented (Figure 3.1A). Refinements of their method as well as the application of patch clamp techniques have supplied us with models for different neural cell membranes. Reliable prediction of membrane voltage
V
as a function of time is possible for arbitrary stimulating currents
I
with proper membrane models.
