Whitehead M L, Lonsbury-Martin B L, Martin G K
Department of Otorhinolaryngology and Communicative Sciences, Baylor College of Medicine, Houston, Texas 77030.
Hear Res. 1991 Feb;51(2):293-300. doi: 10.1016/0378-5955(91)90045-b.
A slow, reversible change in f2-f1 distortion-product otoacoustic emission (DPOAE) amplitude in the absence of correlated changes in 2f1-f2 DPOAE amplitude has been recently reported in anesthetized guinea pigs and gerbils, suggesting a dissociation in the generation of these two emissions. It was proposed that the observed changes in f2-f1 amplitude may represent an efferent influence on cochlear mechanics [Brown, A.M., Hear. Res., 34, 27-38, 1988]. In the present study, a search was made for similar changes in f2-f1 amplitude in awake rabbits. Qualitatively similar variations in f2-f1 DPOAE amplitude, in the absence of 2f1-f2 amplitude variations, were found in all ears tested, supporting the hypothesis of a dissociation of the generators of the two DPOAEs. The behavior of the f2-f1 DPOAE amplitude changes observed here, however, provided no evidence of an efferent involvement.
最近有报道称,在麻醉的豚鼠和沙鼠中,f2 - f1畸变产物耳声发射(DPOAE)幅度出现缓慢、可逆的变化,而2f1 - f2 DPOAE幅度没有相关变化,这表明这两种耳声发射的产生存在分离现象。有人提出,观察到的f2 - f1幅度变化可能代表传出神经对耳蜗力学的影响[Brown, A.M., Hear. Res., 34, 27 - 38, 1988]。在本研究中,我们对清醒兔子的f2 - f1幅度是否存在类似变化进行了研究。在所有测试的耳朵中,均发现f2 - f1 DPOAE幅度存在定性相似的变化,而2f1 - f2幅度没有变化,这支持了两种DPOAE产生源分离的假说。然而,此处观察到的f2 - f1 DPOAE幅度变化行为并未提供传出神经参与的证据。