Bharadwaj Sneha V, Graves Amanda G
Callier Center, University of Texas at Dallas, 811 Synergy Park Boulevard, Richardson, TX 75080, USA.
J Speech Lang Hear Res. 2008 Jun;51(3):629-35. doi: 10.1044/1092-4388(2008/045).
This investigation explored the utility of an acoustic measure, called the discreteness of voicing category (DOVC), in identifying voicing errors in stop consonants produced by children with cochlear implants. Another objective was to examine the perceptual relevance of the DOVC measure and 2 commonly used voice onset time (VOT)-based measures, namely, mean VOT and DeltaVOT (e.g., VOT /t/-VOT /d/).
Phonetic transcription and acoustic analyses were carried out on syllable-initial /t / and /d/ produced by 10 children with cochlear implants. The DOVC was calculated as the difference between the shortest VOT value of a voiceless stop and the longest VOT value of a voiced stop across several productions of each.
Phonetic transcription revealed that 4 of the 10 talkers demonstrated atypical voicing distinctions. Acoustic analyses indicated that the DOVC measure identified these same 4 talkers as producing atypical values, whereas mean VOT and DeltaVOT identified a different set of talkers as demonstrating values outside the normal ranges.
Preliminary findings suggest that the DOVC measure corresponded with perceptual data better than the other acoustic measures examined in the present study. Data indicate that the DOVC measure may provide perceptually relevant information concerning the production of voicing distinctions.
本研究探讨了一种声学指标——嗓音类别离散度（DOVC），在识别人工耳蜗植入儿童塞音发声错误方面的效用。另一个目的是检验DOVC指标以及另外两种常用的基于嗓音起始时间（VOT）的指标，即平均VOT和DeltaVOT（例如，VOT /t/ - VOT /d/）在感知方面的相关性。
对10名人工耳蜗植入儿童发的音节起始音/t/和/d/进行语音转录和声学分析。DOVC的计算方法是，在每个音的多次发音中，清塞音的最短VOT值与浊塞音的最长VOT值之间的差值。
语音转录显示，10名受试者中有4名表现出非典型的嗓音区别。声学分析表明，DOVC指标识别出这4名受试者产生了非典型值，而平均VOT和DeltaVOT则识别出另一组受试者表现出超出正常范围的值。
初步研究结果表明，DOVC指标比本研究中所检验的其他声学指标与感知数据的对应性更好。数据表明，DOVC指标可能提供与嗓音区别产生有关的感知相关信息。
