元音类型对估计的声门下压力和气流的气动测量的影响。

文献信息

中文摘要

引言： 本研究的目的是调查舌高和舌前伸以及声道收缩等因素对声音气动测量（平均气流[MAF]和估计的声门下压力[Psub]）的潜在影响。一个关键问题是，诱发元音的选择是否会对基于MAF或Psub测量的规范预期和随后的临床决策产生实质性影响。
方法： 43名非发音障碍的男性（n = 13）和女性（n = 30）参与者，年龄在18至30岁之间，使用发声气动系统（型号6600，Pentax Medical Inc.）进行测试。MAF是从持续元音/i/、/u/和/α/在舒适的音高和响度下使用舒适持续发声协议测量的。MAF和Psub也从重复音节/pV/中测量，其中V是目标元音（/i, u, α/）。在上述协议中，还测量了元音产生期间的声基频（F0）。持续元音与音节产生任务的顺序以及目标元音在受试者之间进行了平衡。
结果： 对舒适持续发声中的MAF分析显示，元音类型有显著主效应（小效应量），事后分析表明，/i/的MAF显著低于/α/的MAF（分别为0.139 vs. 0.152 L/s）。元音/u/的MAF介于两者之间（0.147 L/s），/i/与/u/以及/α/与/u/之间的MAF差异不显著。相比之下，音节语境中MAF的分析显示元音无显著主效应。在音节语境中获得的Psub测量中，元音主效应显著（小效应量），包含高阻抗元音/i/的音节与包含低阻抗元音/α/的音节相比，Psub显著更高（分别为7.96 vs. 7.54 cm H2O）。包含/u/的音节的Psub平均值再次介于两者之间（7.64 cm H2O），/i/与/u/以及/α/与/u/之间的Psub差异不显著。来自不同元音语境的MAF和Psub测量高度相关。声F0未被观察到是MAF或Psub的显著预测因子。
结论： 尽管元音类型对气动测量的效应通常较小，表明这一发现可能几乎没有实际意义，但本研究的结果支持元音类型对MAF（在舒适持续发声）和音节语境中的Psub测量具有可预测和可测量的影响的观点。元音之间发音差异导致的声门上阻抗变化主要负责元音在MAF和Psub上的差异，而不是可能伴随不同元音产生的喉部活动的F0相关变化。本研究的结果表明，元音类型不应对MAF或Psub的规范预期产生任何实质性影响，线性回归方程可用于在不同元音之间转换MAF和Psub的气动测量，误差相对较小。

英文摘要

INTRODUCTION: The purpose of this study was to investigate the potential effect of factors such as tongue height and advancement and vocal tract constrictions on aerodynamic measures of voice (mean airflow [MAF] and estimated subglottal pressure [Psub]). A key question was whether the choice of elicitation vowel would have a substantial impact on normative expectations and subsequent clinical decision making that may be based on measures of MAF or Psub.
METHOD: Forty-three nondysphonic male (n = 13) and female (n = 30) participants between the ages of 18 and 30 years were tested using the Phonatory Aerodynamic System (Model 6600, Pentax Medical Inc.). MAF was measured from sustained vowels /i/, /u/, and /α/ in their comfortable pitch and loudness using the comfortable sustained phonation protocol. MAF and Psub were also measured from repetitions of the syllable /pV/, where V was the target vowel (/i, u, α/. Measurement of vocal fundamental frequency (F0) during vowel production in the aforementioned protocols was also measured. The order of sustained vowel versus syllable production tasks and the target vowels were counterbalanced across subjects.
RESULTS: Analysis of MAF in comfortable sustained phonation showed a significant main effect of vowel type (small effect size), with post hoc analysis indicating that the MAF observed for /i/ was significantly lower than that observed for /α/ (0.139 vs. 0.152 L/s, respectively). MAF for the vowel /u/ fell in between (0.147 L/s), with differences in MAF between /i/ versus /u/ and /α/ versus /u/ being nonsignificant. In contrast, the analysis of MAF in syllable context showed no significant main effect of vowel. The main effect of vowel was significant for measures of Psub obtained in the syllable context (small effect size), with syllables including the high-impedance vowel /i/ observed to have significantly higher Psub compared with syllables including the low-impedance vowel /α/ (7.96 vs. 7.54 cm H2O, respectively). Mean Psub for the syllables including /u/ was again observed to fall in between (7.64 cm H2O), with differences in Psub between /i/ versus /u/ and /α/ versus /u/ being nonsignificant. Measures of MAF and Psub from different vowel contexts were highly correlated. Vocal F0 was not observed to be a significant predictor of MAF or Psub.
CONCLUSIONS: Although the generally small effect sizes for the effect of vowel type on aerodynamic measures indicate that this finding may be of little practical significance, the results of this study support the view that vowel type has a predictable and measurable effect on measures of MAF (in comfortable sustained phonation) and Psub in syllable context. Supraglottal impedance changes secondary to articulatory differences between vowels are primarily responsible for the differences between vowels on MAF and Psub versus F0-related changes in laryngeal activity that may accompany different vowel productions. The results of this study indicate that vowel type should not have any substantial effect on normative expectations for MAF or Psub, and linear regression equations may be used to convert aerodynamic measures of MAF and Psub between different vowels with relatively little error.