The Relationship Between Pulse Rate and Mandarin Tone Recognition: A Preliminary Study with CCi-Mobile Cochlear Implant Research Processor

Abstract

The aim of this study is to evaluate the effects of pulse rate (i.e., stimulation rate) on Mandarin tone recognition by cochlear implant users. Mandarin tone recognition was measured by using monosyllabic and disyllabic tone data-bases at three pulse rates in cochlear implant users. The three pulse rates included each participant's clinical default pulse rate (i.e., 900 or 1200 pulses per second (pps) for each electrode), 400 pps, and 200 pps. A real-time research speech processor, CCi-Mobile, was used to implement the signal processing strategies. Although the results are variable among participants, there was a trend that the recognition rates of both monosyllabic and disyllabic databases decreased with lower pulse rates, indicating that low pulse rates degrade acoustic cues, like periodicity, for Mandarin tone perception. This study also provided preliminary data for evaluating the CCi-Mobile research processor for the first time in China. The processor could be used for signal processing algorithm development and psychophysical experiments in the future.