ACOUSTIC SIMULATIONS COCHLEAR IMPLANTS TONAL LANGUAGE

数以千计的聋人从人工耳蜗植入中受益。然而，仍然非常需要继续研究以改善人工耳蜗的性能，以便尽可能多的患者可以获得最大的益处。当语音信号以与人工耳蜗的语音处理器类似的方式进行处理，并通过扬声器将输出呈现给听力正常的受试者时，我们可以用人工耳蜗模拟听力。拟议的研究是使用人工耳蜗植入的声学模拟来研究对语音感知很重要的植入刺激的特征。这些特征包括电极数量、电极位置、用于提取信号包络的低通截止频率、模拟的插入深度和激励扩展以及语音处理策略。拟议的研究还将定义植入刺激的时间和频谱特征，这些特征对声调语言（特别是汉语普通话）很重要。声调语言与英语的不同之处在于，单音节词的音高或音调传达词汇意义。听力正常的受试者将被要求对处理后的语音信号进行语音辨别和识别任务。对人工耳蜗植入体重要刺激特征的理解对于未来人工耳蜗植入体的设计和人工耳蜗植入体的临床拟合至关重要。我们关于如何处理重要的语音特征（如人工耳蜗的音调）的知识将导致人工耳蜗的发展，从而使全世界数百万聋人受益。

Thousands of deaf people have benefitted from cochlear implantation. Yet, there is still a great need for continuing research to improve the performance of the cochlear implants so that as many patients as possible may receive maximum benefit. When speech signals are processed in a similar manner to the speech processors of the cochlear implants and the outputs are presented to normal-hearing subjects via loudspeakers, we can simulate the hearing with the cochlear implants. The proposed study is to use acoustic simulations of cochlear implants to study features of implant stimulation that are important for speech perception. Those features include number of electrodes, electrode location, low-pass cut- off frequencies for extracting signal envelopes, simulated insertion depth and spread of excitation, and speech-processing strategies. The proposed study will also define temporal and spectral features of implant stimulation that are important for a tonal language (specifically Mandarin Chinese). A tonal language differs from English in that the pitch or tonality of a monosyllable word conveys lexical meanings. Normal-hearing subjects will be required to perform speech discrimination and recognition tasks on processed speech signals. The understanding of stimulus features important for cochlear implants is essential to designs of future cochlear implants and to clinical fitting of cochlear implants. Our knowledge on how to process important speech feature such as tones for cochlear implants will lead to the development of cochlear implants for tonal languages and thus benefit millions of deaf people around the world.