NEURAL STIMULATION ELECTRODES: GEOMETRIC FACTORS

While stimulating electrode charge delivery and safety performance depends to a large extent on electrochemistry, the utility of neural stimulation devices is geometry dependent at several scales from nanometer to millimeter. The molecular scale of the chemical reaction, the tortuosity properties of the surface, micron scale micromachining, through to the gross physical features of an electrode system all contribute to the distribution and dynamics of current surrounding the device. Here, we explore the effects of geometry at some of these scales with examples of some of the more common forms that electrodes take.