Luo Xin, Fu Qian-Jie, Wu Hung-Pin, Hsu Chuan-Jen
Department of Speech, Language, and Hearing Sciences, Purdue University, 500 Oval Drive, West Lafayette, IN 47907, USA.
Hear Res. 2009 Oct;256(1-2):75-84. doi: 10.1016/j.heares.2009.07.001. Epub 2009 Jul 10.
In Mandarin Chinese, tonal patterns are lexically meaningful. In a multi-talker environment, competing tones may create interference in addition to competing vowels and consonants. The present study measured Mandarin-speaking cochlear implant (CI) users' ability to recognize concurrent vowels, tones, and syllables in a concurrent-syllable recognition test. Concurrent syllables were constructed by summing either one Chinese syllable each from one male and one female talker or two syllables from the same male talker. Each talker produced 16 different syllables (4 vowels combined with 4 tones); all syllables were normalized to have the same overall duration and amplitude. Both single- and concurrent-syllable recognition were measured in 4 adolescent and 4 adult CI subjects, using their clinically assigned speech processors. The results showed no significant difference in performance between the adolescent and adult CI subjects. With single syllables, mean vowel recognition was 90% correct, while tone and syllable recognition were only 63% and 57% correct, respectively. With concurrent syllables, vowel, tone, and syllable recognition scores dropped by 40-60 percentage points. Concurrent-syllable performance was significantly correlated with single-syllable performance. Concurrent-vowel and syllable recognition were not significantly different between the same- and different-talker conditions, while concurrent-tone recognition was significantly better with the same-talker condition. Vowel and tone recognition were better when concurrent syllables contained the same vowels or tones, respectively. Across the different vowel pairs, tone recognition was less variable than vowel recognition; across the different tone pairs, vowel recognition was less variable than tone recognition. The present results suggest that interference between concurrent tones may contribute to Mandarin-speaking CI users' susceptibility to competing-talker backgrounds.
在汉语普通话中，声调模式具有词汇意义。在多说话者环境中，除了元音和辅音相互竞争外，相互竞争的声调也可能产生干扰。本研究在一项同时音节识别测试中，测量了使用人工耳蜗（CI）的普通话使用者识别同时出现的元音、声调及音节的能力。同时音节是通过将一名男性说话者和一名女性说话者各自的一个汉语音节相加，或者将同一名男性说话者的两个音节相加构建而成。每位说话者发出16个不同的音节（4个元音与4种声调组合）；所有音节均进行了标准化处理，使其具有相同的总时长和振幅。使用4名青少年和4名成年人工耳蜗使用者临床配备的言语处理器，对单音节和同时音节识别能力进行了测量。结果显示，青少年和成年人工耳蜗使用者在表现上没有显著差异。对于单音节，元音识别的平均正确率为90%，而声调识别和音节识别的正确率分别仅为63%和57%。对于同时音节，元音、声调及音节识别分数下降了40至60个百分点。同时音节的表现与单音节表现显著相关。在相同说话者和不同说话者条件下，同时元音和音节识别没有显著差异，而在相同说话者条件下，同时声调识别明显更好。当同时音节包含相同的元音或声调时，元音和声调识别表现更好。在不同的元音对中，声调识别的变异性小于元音识别；在不同的声调对中，元音识别的变异性小于声调识别。目前的结果表明，同时声调之间的干扰可能导致使用人工耳蜗的普通话使用者在有竞争说话者的背景环境中更易受到影响。
