Xu Z M, De Vel E, Vinck B, van Cauwenberge P B
Department of Otolaryngology, University Hospital Ghent, Belgium.
Auris Nasus Larynx. 1997 Oct;24(4):333-40. doi: 10.1016/s0385-8146(97)10014-1.
The effects of stimulus rise-fall and plateau times on the middle-latency response (MLR) waveform (Na-Pa amplitude and Pa latency) were investigated in 14 normally hearing subjects and an objective MLR threshold was evaluated at low and middle frequencies in ten normally hearing subjects and ten patients with slope of sensorineural hearing loss, using a selected stimulus-envelope time. After analyzing the effects of envelope times on the MLR waveform and the spectra of tone-pips, it was found that a rise-fall time of 4 ms with a plateau of 2 ms (4-2-4) is an acceptable compromise between a synchronous discharge and frequency specificity for estimating the MLR threshold. The MLR threshold produced by 4-2-4 tone-pips approximated the psychoacoustic threshold at low and middle frequencies in the normal and hearing impaired subjects. This demonstrates the clinical usefulness of the MLR in estimating low- and middle-frequency thresholds.
在14名听力正常的受试者中，研究了刺激上升-下降和平台时间对中潜伏期反应（MLR）波形（Na-Pa振幅和Pa潜伏期）的影响，并使用选定的刺激包络时间，在10名听力正常的受试者和10名感音神经性听力损失斜率患者中，评估了低频和中频的客观MLR阈值。在分析了包络时间对MLR波形和短纯音频谱的影响后，发现4毫秒的上升-下降时间和2毫秒的平台期（4-2-4）是在同步放电和频率特异性之间的可接受折衷，用于估计MLR阈值。由4-2-4短纯音产生的MLR阈值在正常和听力受损受试者的低频和中频处接近心理声学阈值。这证明了MLR在估计低频和中频阈值方面的临床实用性。
