Zajac D J
Craniofacial Center, Department of Dental Ecology, University of North Carolina at Chapel Hill, 27599, USA.
J Commun Disord. 1998 May-Jun;31(3):201-12; quiz 212-3. doi: 10.1016/s0021-9924(97)00050-6.
The purpose of this study was to determine the effects of an intraoral air pressure target on estimation of laryngeal airway resistance (LAR) in normal children. Ten children produced the syllable /pi/ (a) with self-determined normal loudness, (b) with increased loudness, and (c) at a predetermined intraoral air pressure level of 6.5 to 7.5 cm of water. The target pressure level was selected because it was expected to result in estimated subglottal pressures that were lower than those associated with self-determined loudness levels. Results indicated significant differences in estimated subglottal pressure among the three conditions. As expected, estimated subglottal pressures were highest during loud speech and lowest during the pressure target task. LAR values associated with normal loudness were similar to values previously reported for children. The use of the pressure target resulted in LAR values that were reduced by 31% from normal loudness. These resistance values, however, were still greater than those reported for adult speakers at similar subglottal pressure levels. The results are explained relative to preferred loudness levels and vocal tract size differences in children and adults. It is suggested that use of a pressure target during estimation of LAR in children may provide additional data that more accurately reflect the aerodynamic integrity of the larynx. Implications for clinical assessment are discussed.
本研究的目的是确定口腔内气压目标对正常儿童喉气道阻力（LAR）估计值的影响。10名儿童分别在以下三种情况下发出音节/pi/：（a）以自我确定的正常响度；（b）以增加的响度；（c）在6.5至7.5厘米水柱的预定口腔内气压水平下。选择该目标压力水平是因为预计其会导致估计的声门下压力低于与自我确定的响度水平相关的压力。结果表明三种情况下估计的声门下压力存在显著差异。正如预期的那样，大声说话时估计的声门下压力最高，而在压力目标任务期间最低。与正常响度相关的LAR值与先前报道的儿童值相似。使用压力目标导致LAR值比正常响度时降低了31%。然而，这些阻力值仍高于在类似声门下压力水平下成年说话者的报道值。根据儿童和成人的偏好响度水平以及声道大小差异对结果进行了解释。建议在儿童LAR估计过程中使用压力目标可能会提供更准确反映喉部空气动力学完整性的额外数据。并讨论了对临床评估的影响。
