Whitehead M L, Martin G K, Lonsbury-Martin B L
Department of Otorhinolaryngology and Communicative Sciences, Baylor College of Medicine, Houston, Texas 77030.
Hear Res. 1991 Jan;51(1):55-72. doi: 10.1016/0378-5955(91)90007-v.
Recent studies in anesthetized cats suggest that contralateral-sound stimulation acts to suppress ipsilateral neural responses via the medial olivocochlear-efferent system. Activation of this descending efferent pathway presumably influences ipsilateral outer hair cell motility and, thus, cochlear micromechanics, resulting in reduced input to auditory-nerve fibers. The principal aim of the present study was to determine if contralateral-sound stimuli influence the generation of ipsilateral distortion-product otoacoustic emissions, in the ears of awake rabbits. The results showed no effects of contralateral stimuli on these emissions that could not be attributed to the crossed acoustic middle-ear reflex. The findings further indicate that distortion-product otoacoustic emission amplitudes over a wide range of frequencies can be dramatically reduced when the middle-ear reflex is activated.
