Audiology and Deafness Research Group, University of Manchester, Manchester, United Kingdom.
Ear Hear. 2011 Jul-Aug;32(4):485-97. doi: 10.1097/AUD.0b013e31820a77e2.
To assess a novel objective method of measuring response amplitude curves (RACs) using auditory steady state responses in adults.
RACs were recorded in 20 normal-hearing adults. The RACs were measured by recording the changes in the amplitude of the auditory steady state response in the presence of (1) swept frequency narrowband masking noise and (2) fixed narrowband masking noise.
The mean recorded RAC tip frequency for a 2-kHz signal was 2250 Hz for the swept masker method and 2239 Hz for the fixed masker method. The estimated repeatability coefficients, calculated using an assumed mean difference of zero, were 389 Hz for the swept method and 342 Hz for the fixed method.
These initial results indicate that the swept- and fixed-masking methods appear to be viable and fast ways to record RACs in normal-hearing adults. Further work is needed to further optimize the accuracy of the tip frequency estimation and to establish the normative range of tip frequencies over a wide range of test frequencies in normal-hearing and hearing-impaired subjects.
评估一种使用成人听觉稳态反应测量反应幅度曲线(RAC)的新客观方法。
在 20 名听力正常的成年人中记录 RAC。通过记录存在(1)扫频窄带掩蔽噪声和(2)固定窄带掩蔽噪声时听觉稳态反应幅度的变化来测量 RAC。
对于 2 kHz 信号,扫频掩蔽器方法记录的平均 RAC 尖端频率为 2250 Hz,固定掩蔽器方法为 2239 Hz。使用假设平均差为零计算的估计可重复性系数分别为扫频法 389 Hz 和固定法 342 Hz。
这些初步结果表明,扫频和固定掩蔽方法似乎是在听力正常的成年人中记录 RAC 的可行且快速的方法。需要进一步的工作来进一步优化尖端频率估计的准确性,并在正常听力和听力障碍受试者中建立广泛测试频率范围内的尖端频率的正常范围。