Time-frequency analysis of stimulus frequency otoacoustic emissions and their changes with efferent stimulation in guinea pigs

作     者：Maria A. Berezina-Greene John J. Guinan, Jr. 

作者机构：*Speech & Hearing Bioscience and Technology Program Harvard-MIT Division of Health Science and Technology Cambridge Massachusetts USA †Eaton-Peabody Laboratory of Auditory Physiology Massachusetts Eye and Ear Infirmary Boston Massachusetts USA **Department of Otology and Laryngology Harvard Medical School Boston Massachusetts USA 

出 版 物：《AIP Conference Proceedings》 

年 卷 期：2015年第1703卷第1期

学科分类：07[理学] 0702[理学-物理学] 

摘      要：To aid in understanding their origin, stimulus frequency otoacoustic emissions (SFOAEs) were measured at a series of tone frequencies using the suppression method, both with and without stimulation of medial olivocochlear (MOC) efferents, in anesthetized guinea pigs. Time-frequency analysis showed SFOAE energy peaks in 1-3 delay components throughout the measured frequency range (0.5-12 kHz). One component’s delay usually coincided with the phase-gradient delay. When multiple delay components were present, they were usually near SFOAE dips. Below 2 kHz, SFOAE delays were shorter than predicted from mechanical measurements. With MOC stimulation, SFOAE amplitude was decreased at most frequencies, but was sometimes enhanced, and all SFOAE delay components were affected. The MOC effects and an analysis of model data suggest that the multiple SFOAE delay components arise at the edges of the traveling-wave peak, not far basal of the peak. Comparisons with published guinea-pig neural data suggest that the short latencies of low-frequency SFOAEs may arise from coherent reflection from an organ-of-Corti motion that has a shorter group delay than the traveling wave.