The perceptual effects of interphase gap duration in cochlear implant stimulation

Abstract

The most common current pulse shape used for cochlear implants is a biphasic rectangular pulse. The interphase gap (IPG) is the duration of the zero-current portion which lies between the two phases. It is known from single-nerve studies in animals that, as the IPG decreases, the biphasic pulse becomes less efficient in activating the nerve cell. Thus, it can be predicted that stimulation using smaller IPGs will necessitate the use of higher currents to maintain the loudness required by the cochlear implantee. The development of contemporary processing schemes commonly involves the maximization of the rate parameter, and to achieve this in sequential pulsatile stimulation, the IPG as well as..