耳道温度梯度对海拔相关共振偏移及助听器输出的影响

文献信息

中文摘要

背景： 随着越来越多的使用者暴露于高海拔环境，理解海拔如何影响助听器性能日益重要。此前的计算模型预测在第一共振区附近会出现显著的输出下降，但假设耳道温度随环境温度变化，可能高估了共振相关效应。方法：本研究纳入了耳道温度梯度敏感性模型，并使用两种代表性听力损失曲线配以National Acoustic Laboratories-Non-Linear Version 2处方，评估其对海平面（0 m）和4572 m处预测助听器输出及言语可听度的影响。结果：在所有温度梯度条件下，峰值衰减降至小于3 dB，而原始均匀温度模型约为5.7 dB，并在最强体温调节条件下进一步降至约1.8-1.9 dB。更细分辨率的18频带美国国家标准学会式言语可懂度指数分析显示模型间差异很小，在4572 m处最大绝对差异约为N3听力图的0.011和N6听力图的0.002。结论：这些发现表明，纳入温度梯度模型可显著降低预测的海拔相关共振效应，而不会相应大幅改变预测的言语可听度。

英文摘要

Understanding how altitude influences hearing aid performance is increasingly important as more users are exposed to high-altitude environments. A previous computational model predicted substantial output reductions near the first-resonance region but assumed that ear canal temperature followed ambient temperature, potentially overestimating resonance-related effects. The present study incorporated an ear canal temperature-gradient sensitivity model and evaluated its effects on predicted hearing aid output and speech audibility at sea level (0 m) and 4572 m using two representative hearing-loss profiles fitted with the National Acoustic Laboratories-Non-Linear Version 2 prescription. Across all temperature-gradient conditions, peak attenuation was reduced to less than 3 dB, compared with approximately 5.7 dB in the original uniform-temperature model, and decreased further to approximately 1.8-1.9 dB under the strongest thermal-regulation condition. A finer-resolution 18-band American National Standards Institute-style Speech Intelligibility Index analysis showed only small between-model differences, with maximum absolute differences at 4572 m of approximately 0.011 for the N3 audiogram and 0.002 for the N6 audiogram. These findings suggest that incorporating the temperature-gradient model substantially reduces predicted altitude-related resonance effects without producing a correspondingly large change in predicted speech audibility.