Hocevar-Boltezar Irena, Vatovec Jagoda, Gros Anton, Zargi Miha
University Department of Otorhinolaryngology and Head & Neck Surgery, Zaloska 2, SI-1000 Ljubljana, Slovenia.
Int J Pediatr Otorhinolaryngol. 2005 Dec;69(12):1635-40. doi: 10.1016/j.ijporl.2005.03.045. Epub 2005 Jun 6.
Some of the voice characteristics of deaf people differ considerably from those of speakers with normal hearing. After a cochlear implantation, auditory control of voice production is possible and the quality of the voice is improved. The aim of this study was to investigate the changes in some of the voice parameters in deaf children after cochlear implantation.
Thirty-one prelingually deafened children implanted unilaterally at the age of 2.5-13 years were included in the study. For all of the children an acoustic analysis (Multi-Dimensional Voice Program, Kay Elemetrics Corp., USA) of the Slovene vowel 'a' was performed before cochlear implantation and 6, 12 and 24 months after the implantation. The fundamental frequency (F0), jitter, shimmer and noise-to-harmonic ratio (NHR) were compared before and after the implantation. The results of the acoustic analyses were compared for the children who were implanted before or at the age of 4 years and the children who were implanted after the age of 4 years.
After the cochlear implantation the fundamental frequency did not change significantly. However, an improvement was noticed in the measurements of jitter (p=0.006) and shimmer (p=0.021) as early as 6 months after the implantation. The noise-to-harmonic ratio improved (p=0.013) 24 months after the implantation. The children implanted before or at the age of 4 years showed a significant improvement in jitter (p=0.003) and shimmer (p=0.004) as early as 6 months and in noise-to-harmonic ratio (p=0.021) 12 months after the implantation. In the children implanted after the age of 4 years the only significant change was detected in F0 (p=0.045), 12 months after the implantation, and in Shimmer (p=0.017), 24 months after the implantation.
The results of the present study have confirmed that cochlear implantation enables auditory moment-to-moment control of pitch and loudness. The determination of jitter and shimmer in the vowel 'a' sample proved to be a good and early indicator of improved phonation control, even in young children. The deaf children who were implanted before the age of 4 years improved their voice control more quickly and to a greater extent than the children implanted after the age of 4 years.
聋人的一些嗓音特征与听力正常的说话者有很大差异。人工耳蜗植入后，语音产生的听觉控制成为可能，嗓音质量得到改善。本研究的目的是调查人工耳蜗植入后聋儿某些嗓音参数的变化。
本研究纳入了31名单侧植入人工耳蜗的语前聋儿童，年龄在2.5至13岁之间。对所有儿童在人工耳蜗植入前以及植入后6、12和24个月进行斯洛文尼亚语元音“a”的声学分析（多维嗓音程序，美国凯公司）。比较植入前后的基频（F0）、抖动、闪烁和噪声谐波比（NHR）。对4岁及4岁以前植入人工耳蜗的儿童和4岁以后植入人工耳蜗的儿童的声学分析结果进行比较。
人工耳蜗植入后基频没有显著变化。然而，早在植入后6个月，抖动（p = 0.006）和闪烁（p = 0.021）的测量值就有所改善。植入后24个月，噪声谐波比有所改善（p = 0.013）。4岁及4岁以前植入人工耳蜗的儿童早在植入后6个月抖动（p = 0.003）和闪烁（p = 0.004）就有显著改善，植入后12个月噪声谐波比（p = 0.021）有显著改善。4岁以后植入人工耳蜗的儿童，仅在植入后12个月F0（p = 0.045）和植入后24个月闪烁（p = 0.017）有显著变化。
本研究结果证实，人工耳蜗植入能够实现对音高和响度的瞬间听觉控制。在元音“a”样本中测定抖动和闪烁被证明是改善发声控制的良好且早期的指标，即使在幼儿中也是如此。4岁以前植入人工耳蜗的聋儿比4岁以后植入人工耳蜗的儿童更快且更大程度地改善了他们的嗓音控制。
