Zhang Jianxing, McPherson Bradley
Division of Speech and Hearing Sciences, Faculty of Education, University of Hong Kong, Hong Kong SAR, China.
Folia Phoniatr Logop. 2008;60(4):179-87. doi: 10.1159/000128276. Epub 2008 Apr 29.
To investigate the impact of low frequency cuts (LCs) in hearing aid frequency response on Mandarin tone and vowel perception at varying signal-to-noise ratios (S/N ratios).
Four LC conditions were reviewed, using a programmable, behind-the-ear hearing aid: no LC (NoLC), a 6-dB/octave LC (LC6), a 12-dB/octave LC (LC12), and an 18-dB/octave LC (LC18). Five S/N ratios for speech to white noise were selected: +10 dB, +5 dB, 0 dB, -5 dB and -10 dB. Speech and noise stimuli were presented to 25 normal-hearing, native Mandarin-speaking listeners monaurally.
Tone and vowel recognition scores were high for subjects in all experimental conditions except for LC18 and S/N -10 dB. The LCs had minimal impact on tone perception in the positive S/N and S/N 0 conditions. Significant differences for tone recognition were found between the NoLC and LC6, and the LC6 and LC18 conditions with negative S/N ratios. Significant differences in vowel recognition were observed between the LC12 and LC18 settings, at all S/N conditions.
LC hearing aid settings may negatively impact on vowel recognition, and may adversely affect Mandarin tone recognition in adverse noise conditions, in normal-hearing listeners.
研究助听器频率响应中的低频削减（LC）对不同信噪比（S/N比）下普通话声调及元音感知的影响。
使用一台可编程的耳背式助听器，评估了四种LC条件：无LC（NoLC）、6 dB/倍频程LC（LC6）、12 dB/倍频程LC（LC12）和18 dB/倍频程LC（LC18）。选取了语音与白噪声的五种S/N比：+10 dB、+5 dB、0 dB、-5 dB和-10 dB。语音和噪声刺激以单耳方式呈现给25名听力正常、以普通话为母语的听众。
除LC18和S/N为-10 dB的情况外，所有实验条件下受试者的声调及元音识别分数都很高。在正S/N和S/N为0的条件下，LC对声调感知的影响最小。在负S/N比条件下，NoLC与LC6以及LC6与LC18条件之间，声调识别存在显著差异。在所有S/N条件下，LC12和LC18设置之间的元音识别存在显著差异。
在听力正常的听众中，LC助听器设置可能会对元音识别产生负面影响，并且在不利的噪声条件下可能会对普通话声调识别产生不利影响。
