Department of Speech and Hearing Science, University of Illinois at Urbana-Champaign, 901 South Sixth Street, Champaign, Illinois 61820, USA.
J Acoust Soc Am. 2019 Mar;145(3):1529. doi: 10.1121/1.5094766.
The medial olivocochlear (MOC) efferent system modifies cochlear output to aid signal detection in noise, but the precise role of efferents in speech-in-noise understanding remains unclear. The current study examined the contribution of the MOC reflex for speech recognition in noise in 30 normal-hearing young adults (27 females, mean age = 22.7 yr). The MOC reflex was assessed using contralateral inhibition of transient-evoked otoacoustic emissions. Speech-in-noise perception was evaluated using the coordinate response measure presented in ipsilateral speech-shaped noise at signal-to-noise ratios (SNRs) ranging from -12 to 0 dB. Performance was assessed without and with the presence of contralateral noise to activate the MOC reflex. Performance was significantly better with contralateral noise only at the lowest SNR. There was a trend of better performance with increasing contralateral inhibition at the lowest SNR. Threshold of the psychometric function was significantly correlated with contralateral inhibition. Response time on the speech task was not significantly correlated with contralateral inhibition. Results suggest that the MOC reflex contributes to listening in low SNRs and the relationship between the MOC reflex and perception is highly dependent upon the task characteristics.
内侧橄榄耳蜗（MOC）传出系统调节耳蜗输出，以帮助在噪声中检测信号，但传出系统在语音理解中的精确作用仍不清楚。本研究在 30 名听力正常的年轻成年人（27 名女性，平均年龄 22.7 岁）中检查了 MOC 反射对噪声中语音识别的贡献。使用对侧瞬态诱发耳声发射的抑制来评估 MOC 反射。使用在同侧语音成形噪声中呈现的坐标反应测量来评估语音在噪声中的感知，信号噪声比（SNR）范围从-12 到 0 dB。在没有和存在对侧噪声以激活 MOC 反射的情况下评估性能。只有在最低 SNR 时，有对侧噪声的情况下性能显著更好。在最低 SNR 时，随着对侧抑制的增加，性能有更好的趋势。心理物理函数的阈值与对侧抑制显著相关。语音任务的反应时间与对侧抑制无显著相关性。结果表明，MOC 反射有助于在低 SNR 下聆听，并且 MOC 反射和感知之间的关系高度依赖于任务特征。
