Nerve fiber stimulation using plural equally active electrodes

Abstract

Nerve fiber stimulation is disclosed to substantially increase the activity of the then selected nerve fibers, with optimization being achieved through utilization of electrical pulses that are caused to occur in a predetermined pattern with respect to polarity, spacing, frequency and duration so as to interact with the electroneurophysiological characteristics of the particular nerve fibers then to be electrically stimulated. Bi-phased pulse pairs are repeatedly generated and applied to the nerve fibers to be stimulated through plural active electrodes with the first pulse of each applied pulse pair being a positive polarity pulse causing the nerve to be set into the refractory period, while the second pulse of each applied pulse pair is a negative polarity pulse that is made to occur substantially at the end of the refractory period for the particular nerve fibers then being stimulated to thereby excite those nerve fibers, and the pulse pairs are repeated at a rate based upon the timewise occurrence of the enhanced excitability condition of the nerve fibers then being stimulated. By stimulation of each of a plurality of electrodes using positive/negative pulse pairs, all electrodes can be made substantially equally active. Since additional pulses occurring during the period closely following occurrence of a pulse pair do not normally adversely affect performance, additional pulses can be added to form additional pulse pairs such that a plurality of electrodes can be made substantially equally active to thereby enhance overall achievement of optimum stimulation.