Effect of Contralateral Medial Olivocochlear Feedback on Perceptual Estimates of Cochlear Gain and Compression.

摘要: The active cochlear mechanism amplifies responses to low-intensity sounds, compresses the range of input sound intensities a smaller output range, and increases frequency selectivity. gain can be modulated by medial olivocochlear (MOC) efferent system, creating possibility top-down control at earliest level auditory processing. In humans, MOC function has mostly been measured suppression otoacoustic emissions (OAEs), typically as result activation contralateral elicitor sound. exact relationship between OAE reduction, however, remains unclear. Here, we effect on perceptual estimates compression, obtained using established temporal masking curve (TMC) method. measurements were taken signal 2 kHz compared with click-evoked suppression. was broadband noise, set pressure 54 dB avoid triggering middle ear muscle reflex. Despite its low level, had significant TMCs, consistent reduction in gain. amount estimated 4.4 dB average, corresponding around 18 % without-elicitor As result, compression exponent increased from 0.18 0.27.