Korczak Peggy A, Sherlock LaGuinn P, Hawley Monica L, Formby Craig
Department of Audiology, Speech Language Pathology and Deaf Studies, Towson University, Towson, Maryland.
Army Hearing Division, United States Public Health Center, Aberdeen Proving Ground, Aberdeen, Maryland; National Military Audiology and Speech Pathology Center, Walter Reed National Military Medical Center, Bethesda, Maryland.
Semin Hear. 2017 Feb;38(1):94-114. doi: 10.1055/s-0037-1598067.
This study characterizes changes in response properties of toneburst-evoked auditory brainstem responses (ABRs) and/or middle latency responses (MLRs) as a function of perceived loudness and physical intensity of these stimuli and delineates the range of levels corresponding to categorical loudness judgments for these stimuli. ABRs/MLRs were recorded simultaneously to 500- and 2,000-Hz tonebursts in 10 normal-hearing adults at levels corresponding to each listener's loudness judgments for four categories on Contour Test of Loudness. Group mean ABR wave V and MLR wave Pa latency values increased significantly as loudness judgments decreased. Group mean amplitude values for ABR wave V-V' and MLR wave Na-Pa increased as the listeners' categorical judgments increased. Listeners assigned a broad range (30 to 40 dB) of stimulus intensities when judging loudness of these stimuli within a specific loudness category. This was true for all four loudness categories and both frequencies. Thus, it appears that tone-evoked ABR/MLR response measures reflect, in part, the listener's perception of loudness. Response latencies are a more sensitive indicator of listener's loudness percept than corresponding response amplitudes. An appreciable range of signal levels was judged to be categorically equivalent across listeners. Thus, limiting how loudness judgments can be applied to prescriptive hearing aid fittings in individuals who cannot provide accurate loudness judgments.
本研究描述了短纯音诱发的听觉脑干反应（ABR）和/或中潜伏期反应（MLR）的反应特性随这些刺激的响度感知和物理强度的变化，并划定了与这些刺激的分类响度判断相对应的强度范围。在10名听力正常的成年人中，同时记录了对应于每个听众在响度等高线测试中对四个类别的响度判断水平下，500赫兹和2000赫兹短纯音诱发的ABR/MLR。随着响度判断的降低，ABR波V和MLR波Pa的组平均潜伏期值显著增加。随着听众分类判断的增加，ABR波V-V'和MLR波Na-Pa的组平均幅度值增加。当在特定响度类别内判断这些刺激的响度时，听众分配了较宽范围（30至40分贝）的刺激强度。对于所有四个响度类别和两个频率都是如此。因此，似乎短纯音诱发的ABR/MLR反应测量部分反映了听众的响度感知。反应潜伏期比相应的反应幅度更能敏感地反映听众的响度感知。在不同听众中，相当范围的信号强度被判断为分类等效。因此，这限制了响度判断在无法提供准确响度判断的个体中应用于助听器处方适配的方式。
