Vandali Andrew E, Dawson Pam W, Arora Komal
a The Hearing CRC , Carlton , Victoria , Australia.
b The Bionics Institute , East Melbourne , Victoria , Australia , and.
Int J Audiol. 2017;56(sup2):S74-S85. doi: 10.1080/14992027.2016.1190872. Epub 2016 Jun 22.
To evaluate the effectiveness of an experimental pitch-coding strategy for improving recognition of Mandarin lexical tone in cochlear implant (CI) recipients.
Adult CI recipients were tested on recognition of Mandarin tones in quiet and speech-shaped noise at a signal-to-noise ratio of +10 dB; Mandarin sentence speech-reception threshold (SRT) in speech-shaped noise; and pitch discrimination of synthetic complex-harmonic tones in quiet. Two versions of the experimental strategy were examined: (OPAL) linear (1:1) mapping of fundamental frequency (F0) to the coded modulation rate; and (OPAL+) transposed mapping of high F0s to a lower coded rate. Outcomes were compared to results using the clinical ACE™ strategy.
Five Mandarin speaking users of Nucleus® cochlear implants.
A small but significant benefit in recognition of lexical tones was observed using OPAL compared to ACE in noise, but not in quiet, and not for OPAL+ compared to ACE or OPAL in quiet or noise. Sentence SRTs were significantly better using OPAL+ and comparable using OPAL to those using ACE. No differences in pitch discrimination thresholds were observed across strategies.
OPAL can provide benefits to Mandarin lexical tone recognition in moderately noisy conditions and preserve perception of Mandarin sentences in challenging noise conditions.
评估一种实验性音调编码策略对改善人工耳蜗（CI）植入者普通话词汇声调识别的有效性。
对成年CI植入者进行测试，内容包括在安静环境以及信噪比为+10 dB的言语噪声环境下对普通话声调的识别；言语噪声环境下的普通话句子言语接受阈值（SRT）；以及安静环境下对合成复谐音调的音调辨别。研究了该实验策略的两个版本：（OPAL）基频（F0）到编码调制率的线性（1:1）映射；以及（OPAL+）将高F0转置映射到较低编码率。将结果与使用临床ACE™策略的结果进行比较。
五名使用Nucleus®人工耳蜗的普通话使用者。
与ACE相比，在噪声环境下使用OPAL时，词汇声调识别有小但显著的益处，但在安静环境下没有；与ACE或OPAL相比，在安静或噪声环境下使用OPAL+时均无此益处。使用OPAL+时句子SRT显著更好，使用OPAL时与使用ACE时相当。各策略之间在音调辨别阈值上未观察到差异。
OPAL可在中等噪声条件下对普通话词汇声调识别提供益处，并在具有挑战性的噪声条件下保持对普通话句子的感知。
