Purcell David W, Van Roon Patricia, John M Sasha, Picton Terence W
The Rotman Research Institute, Baycrest Centre for Geriatric Care, Toronto, Ontario, Canada.
J Acoust Soc Am. 2006 May;119(5 Pt 1):2869-80. doi: 10.1121/1.2191616.
The purpose of this research was to simultaneously estimate processing delays in the cochlea and brainstem using the same acoustic stimuli. Apparent latencies were estimated from ear canal measurements of 2f1-f2 distortion product otoacoustic emissions (DPOAEs), and scalp recordings of the f2-f1 envelope following response (EFR). The stimuli were equal level tone pairs (65 dB SPL) with the upper tone f2 set at either 900 or 1800 Hz to fix the initiation site of the DPOAE and EFR. The frequency of f1 was swept continuously between frequency limits chosen to keep the EFR response between 150 and 170 Hz. The average DPOAE latencies were 9.6 and 6.2 ms for f2 =900 and 1800 Hz, and the corresponding EFR latencies were 12.4 and 8.8 ms. In a control condition, a third (suppressor) tone was added near the DPOAE response frequency to evaluate whether the potential source at fdp was contributing significantly to the measured emission. DPOAE latency is the sum of both inward and outward cochlear delays. The EFR apparent latency is the sum of inward cochlear delay and neural processing delay. Neural delay was estimated as approximately 5.3 ms for both frequencies of stimulation.
本研究的目的是使用相同的声学刺激同时估计耳蜗和脑干中的处理延迟。通过耳道测量2f1-f2畸变产物耳声发射（DPOAE）以及f2-f1包络跟随反应（EFR）的头皮记录来估计表观潜伏期。刺激为等响度音对（65 dB SPL），高音f2设置为900或1800 Hz，以确定DPOAE和EFR的起始部位。f1的频率在选定的频率范围内连续扫描，以使EFR反应保持在150至170 Hz之间。对于f2 = 900和1800 Hz，平均DPOAE潜伏期分别为9.6和6.2 ms，相应的EFR潜伏期分别为12.4和8.8 ms。在对照条件下，在DPOAE反应频率附近添加第三个（抑制）音，以评估fdp处的潜在源是否对测量的发射有显著贡献。DPOAE潜伏期是耳蜗内向和外向延迟的总和。EFR表观潜伏期是耳蜗内向延迟和神经处理延迟的总和。两种刺激频率下的神经延迟估计约为5.3 ms。
