Fowler C G, Mikami C M
Veterans Administration Medical Center, Long Beach, CA.
J Speech Hear Res. 1992 Feb;35(1):216-21. doi: 10.1044/jshr.3501.216.
The purpose of this study was to determine whether the masking-level difference (MLD) obtained with the late (P2) auditory evoked potentials has characteristics similar to those reported for the behavioral MLD with respect to the effects of noise level. Psychoacoustic studies have shown that the magnitude of the MLD increases as a function of the noise level. In the present study, P2 thresholds were measured in SoNo (signals and noise in phase at the ears) and S pi No (signals out of phase and noise in phase at the ears) conditions for noise levels of 0-60 dB pressure spectrum level (Lps). Subjects were 5 normal-hearing young adults. The difference in SoNo and S pi No thresholds, or the MLD, increased linearly as the noise levels increased through 60 dB Lps, whereas the behavioral MLD magnitude is reported to saturate at high noise levels. These results suggest that the late-potential MLD reflects characteristics similar to, but not identical with, those of the behavioral MLD.
本研究的目的是确定利用晚期（P2）听觉诱发电位获得的掩蔽级差（MLD）在噪声水平影响方面是否具有与行为学MLD所报告的特征相似的特性。心理声学研究表明，MLD的大小随噪声水平的变化而增加。在本研究中，针对0至60分贝声压谱级（Lps）的噪声水平，在SoNo（双耳信号与噪声同相）和S pi No（双耳信号异相且噪声同相）条件下测量P2阈值。受试者为5名听力正常的年轻成年人。随着噪声水平增加至60 dB Lps，SoNo和S pi No阈值之差即MLD呈线性增加，而据报道行为学MLD大小在高噪声水平时会趋于饱和。这些结果表明，晚期电位MLD反映出与行为学MLD相似但不完全相同的特征。
