Despite widespread clinical use, the theoretical framework by which to understand safety of electrical stimulation through implanted electrodes is surprisingly limited. Most of our current understanding of stimulation safety was phenomenologically determined in the 80s and 90s using very limited electrode geometries, materials, stimulation systems, and stimulation locations. Current benchtop testing of electrode safety to support submissions to the Food and Drug Administration (FDA) is predominantly focused on identifying the applied charge density that drives the hydrolysis of water at the electrode/electrolyte interface. In this proposal, we seek to validate, optimize, and distribute a benchtop testing framework that more accurately predicts chronic in-vivo safety issues. This framework is extensible to coated microelectrode designs, including high-density and/or thin-film arrays, as well as to novel stimulation waveforms – both of which are critically enabling for next-generation minimally invasive neuromodulation therapies.
