| 摘要 |
A device is described for stimulating the auditory transmission branch of the 8th nerve. It uses electrodes designed to restrict the electrical field to the region of their respective nerve fiber group and produce a gradient field for each channel such that the latency characteristics of the nerve fibers in a given channel will cause a sequential firing (streaming) of the nerve fibers during a portion of the channel stimulus pulse. In the analog system the nerve fiber channels are stimulated in sequence but with their stimulus overlapping their previous channel by an amount equal to the shortest latency period of said channel. During the period when a stimulus pulse is causing nerve fiber streaming the pulse amplitude is modulated with the audio information. In addition during the nerve fiber streaming either electrical means or the shape of the probe compensate for the strength-duration characteristics of the individual nerve fibers. In the digital system there is no streaming as there is a single firing time for nerve fibers in a channel. The channel overlap exists over a number of channels and the audio modulation is in the form of frequency modulation of the channel sequence frequency.
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