Figure 7.

Thermal block length scales with the square root of axon diameter. (A) Thermal block length scales linearly with the square root of axon diameter in the unmodified Hodgkin/Huxley model, and length decreases with increasing temperature. (B) Thermal block length scales linearly with the square root of axon diameter in the modified Hodgkin/Huxley model, and the minimum length required for thermal block decreases with increasing temperature. (C) Expanded view of region highlighted by a square in panel (B). The linear relationship between the square root of axon diameter and threshold block length is observed for axon diameters similar to those of vertebrate unmyelinated C fibers.