Cai Jieqing, Liu Yimeng, Yao Minyun, Xu Muqing, Zhang Hongzheng
Department of Otolaryngology Head & Neck Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China 510282.
Neural Plast. 2020 Jul 22;2020:4576729. doi: 10.1155/2020/4576729. eCollection 2020.
Music perception in cochlear implant (CI) users is far from satisfactory, not only because of the technological limitations of current CI devices but also due to the neurophysiological alterations that generally accompany deafness. Early behavioral studies revealed that similar mechanisms underlie musical and lexical pitch perception in CI-based electric hearing. Although neurophysiological studies of the musical pitch perception of English-speaking CI users are actively ongoing, little such research has been conducted with Mandarin-speaking CI users; as Mandarin is a tonal language, these individuals require pitch information to understand speech. The aim of this work was to study the neurophysiological mechanisms accounting for the musical pitch identification abilities of Mandarin-speaking CI users and normal-hearing (NH) listeners. Behavioral and mismatch negativity (MMN) data were analyzed to examine musical pitch processing performance. Moreover, neurophysiological results from CI users with good and bad pitch discrimination performance (according to the just-noticeable differences (JND) and pitch-direction discrimination (PDD) tasks) were compared to identify cortical responses associated with musical pitch perception differences. The MMN experiment was conducted using a passive oddball paradigm, with musical tone C4 (262 Hz) presented as the standard and tones D4 (294 Hz), E4 (330 Hz), G#4 (415 Hz), and C5 (523 Hz) presented as deviants. CI users demonstrated worse musical pitch discrimination ability than did NH listeners, as reflected by larger JND and PDD thresholds for pitch identification, and significantly increased latencies and reduced amplitudes in MMN responses. Good CI performers had better MMN results than did bad performers. Consistent with findings for English-speaking CI users, the results of this work suggest that MMN is a viable marker of cortical pitch perception in Mandarin-speaking CI users.
人工耳蜗（CI）使用者的音乐感知能力远不能令人满意，这不仅是因为当前CI设备存在技术限制，还由于耳聋通常伴随的神经生理改变。早期行为学研究表明，基于CI的电听觉中，音乐音高感知和词汇音高感知有着相似的机制。尽管针对说英语的CI使用者的音乐音高感知的神经生理学研究正在积极开展，但针对说普通话的CI使用者的此类研究却很少；由于普通话是一种声调语言，这些个体需要音高信息来理解语音。这项工作的目的是研究解释说普通话的CI使用者和听力正常（NH）听众音乐音高识别能力的神经生理机制。分析行为数据和失配负波（MMN）数据，以检验音乐音高处理能力。此外，比较了在音高辨别性能良好和较差的CI使用者（根据恰可察觉差异（JND）和音高方向辨别（PDD）任务）的神经生理学结果，以确定与音乐音高感知差异相关的皮层反应。MMN实验采用被动oddball范式进行，以音乐音调C4（262Hz）作为标准音，以音调D4（294Hz）、E4（330Hz）、G#4（415Hz）和C5（523Hz）作为偏差音。CI使用者表现出比NH听众更差的音乐音高辨别能力，这体现在音高识别的JND和PDD阈值更大，以及MMN反应的潜伏期显著延长和波幅减小。CI表现良好者的MMN结果优于表现较差者。与说英语的CI使用者的研究结果一致，这项工作的结果表明，MMN是说普通话的CI使用者皮层音高感知的一个可行指标。
