A simulation study of generation of unidirectionally propagated action potentials with bipolar electrodes

Electrical stimulation of unmyelinated nerve fibers was analyzed, using bipolar point electrodes in a simple volume conductor model and a dynamic model of Hodgkin-Huxley. The cathodal excitation threshold, the anodal block threshold and the virtual cathodal excitation threshold were calculated by a numerical method with axons of different radii. The results show that the rectangular stimulation pulse should have an appropriate width and the two stimulation electrodes should be placed much closely in order to generate unidirectionally propagated action potentials (UPAPs) and use less stimulation energy