Souza Natalie N, Dhar Sumitrajit, Neely Stephen T, Siegel Jonathan H
Department of Communication Sciences and Disorders and Knowles Hearing Center, Northwestern University, 2240 Campus Drive, Evanston, Illinois 60208.
Boys Town National Research Hospital, 555 North 30th Street, Omaha, Nebraska 68131.
J Acoust Soc Am. 2014 Oct;136(4):1768-87. doi: 10.1121/1.4894787.
The reliability of nine measures of the stimulus level in the human ear canal was compared by measuring the sensitivity of behavioral hearing thresholds to changes in the depth of insertion of an otoacoustic emission probe. Four measures were the ear-canal pressure, the eardrum pressure estimated from it and the pressure measured in an ear simulator with and without compensation for insertion depth. The remaining five quantities were derived from the ear-canal pressure and the Thévenin-equivalent source characteristics of the probe: Forward pressure, initial forward pressure, the pressure transmitted into the middle ear, eardrum sound pressure estimated by summing the magnitudes of the forward and reverse pressure (integrated pressure) and absorbed power. Two sets of behavioral thresholds were measured in 26 subjects from 0.125 to 20 kHz, with the probe inserted at relatively deep and shallow positions in the ear canal. The greatest dependence on insertion depth was for transmitted pressure and absorbed power. The measures with the least dependence on insertion depth throughout the frequency range (best performance) included the depth-compensated simulator, eardrum, forward, and integrated pressures. Among these, forward pressure is advantageous because it quantifies stimulus phase.
通过测量行为听力阈值对耳声发射探头插入深度变化的敏感性，比较了人耳道中刺激水平的九种测量方法的可靠性。其中四种测量方法是耳道压力、据此估算的鼓膜压力以及在有和没有插入深度补偿的耳模拟器中测量的压力。其余五个量是从耳道压力和探头的戴维南等效源特性推导出来的：正向压力、初始正向压力、传入中耳的压力、通过将正向和反向压力的大小相加估算出的鼓膜声压（积分压力）以及吸收功率。在26名受试者中，将探头插入耳道相对较深和较浅的位置，测量了从0.125至20kHz的两组行为阈值。对插入深度依赖性最大的是传输压力和吸收功率。在整个频率范围内对插入深度依赖性最小（性能最佳）的测量方法包括深度补偿模拟器、鼓膜、正向和积分压力。其中，正向压力具有优势，因为它可以量化刺激相位。
