Stimulation of small diameter myelinated and unmyelinated abdominal vagal neurons using high frequency pulses

The voltage required to stimulate small diameter myelinated (Adelta fibres) and unmyelinated (C fibres) neurons consistently is so large that it is unsafe for chronic vagal stimulation. We present here a solution that reduces by 80% the amount of electrical charge necessary to produce action potential. These solutions were tested in a porcine model that allowed simultaneously to locate the origin of the afferent neurons, to stimulate the vagal trunks at distance from the recording electrode and to record the evoked activity of one neuron using the single afferent method. The reduction in current supplied by the most effective pulse pattern makes possible to incorporate this solution in an implanted device without damaging the vagal nerve.