声电信号对双模式人工耳蜗使用者的言语音乐感知的贡献及二者相互作用机制研究

Cochlear implant (CI) users have difficulty understanding speech in noisy listening conditions and perceiving music. Aided residual acoustic hearing in the contralateral ear can mitigate these limitations. The benefits of combined electric and acoustic hearing for speech perception are well documented. In general, combined device performance is better than CI-only performance, but outcomes may be subject- and/or task-dependent. In contrast to speech recognition, music perception has not been as deeply investigated with bimodal or EAS listeners. The previous studies demonstrate a widely ranging contribution of acoustic hearing to bimodal and EAS users. However, differences in test paradigms and stimuli in speech and music testing can make it difficult to assess the relative contributions of each device. The previous studies also demonstrated a number of implications for mapping bimodal listeners by which could improve the benefit of bimodal stimulation. Noted that the Mandarin Chinese is tonal language, which is different with English. Previous studies had showed that there is significant correlation between lexical tone recognition and music perception. As such, we hypothesized: The contribution of electric and acoustic hearing may be different between Mandarin Chinese and English. Moreover, better hearing aid (HA) mapping may improve the benefit of bimodal stimulation. So in the present study, the Mandarin Sung Speech Corpus (SSC) will be created, which could control the “better ear effect”. The SSC contains 50 monosyllable words sung over an octave range and can be used to test both speech and music perception using the same stimuli. In addition, we will do the balance of the loudness and frequency allocation between HA and CI. The performance will be compared in all conditions with different parameter setting.

人工耳蜗（CI）联合助听器（HA）的声电联合刺激模式的应用逐渐广泛，但使用者的言语音乐感知获益并不一致，这使研究双模式刺激下声、电信号对不同感知表现的影响及二者的相互作用成为目前研究热点。考虑已往研究未排除“优势耳”效应，以及汉语声调与旋律音高的内在联系，我们假设声电信号对讲汉语普通话的双模式CI使用者的言语、音乐感知的影响及二者可能的相互作用可能与已往研究有所不同，且我们推测通过优化声信号处理参数平衡声电信号，可使CI使用者获益最大化。为验证假说，我们拟研发集音乐言语信息于一体的测听材料，排除优势耳效应，应用此材料更客观的评估声电信号对言语音乐感知的影响，并探索声、电信号的相互作用。另外我们从HA的信号处理角度出发，个体化调节HA的信号处理参数以达到HA与CI的匹配，通过对比分析不同参数设置下的感知表现来验证声电信号的相互作用，为提高双模式CI使用者的获益提供一定理论依据。

虽然一侧人工耳蜗（CI）联合对侧助听器（HA）的双模式的应用越来越广泛，但这种双模式使用者的听觉获益并不一致，这使研究双模式聆听方式下声、电信号对不同感知表现的影响及二者的相互作用成为目前研究热点。由于研究方法学的差异，导致已有研究结果并无可比性及推广性。并且由于汉语与音高信息本身的内在联系，声电信号对讲汉语普通话的双模式使用者的言语、音乐感知的贡献及二者可能的相互作用模式是否会有特殊性。项目通过应用自主研发的测试软件(闭集中文短句测试)，对讲汉语普通话双模式使用者的声调、困难言语及音乐感知进行了系统评估，通过严控声学信息，明确了通过助听器利用低频声信号对汉语普通话四声调的感知影响，同时发现声信号对困难语境的帮助更加显著，且这种帮助与困难程度及低频残余听力水平显著相关。同时也揭示了CI使用者声调与音乐感知的内在联系，从而探索提高CI使用者声调感知表现的新方法。研究结果对提高CI使用者的术前指导及术后康复水平提供了重要实验依据。