Effect of contralateral medial olivocochlear feedback on perceptual estimates of cochlear gain and compression

The active cochlear mechanism amplifies responses to low-intensity sounds, compresses the range of input sound intensities to a smaller output range, and increases cochlear frequency selectivity. The gain of the active mechanism can be modulated by the medial olivocochlear (MOC) efferent system, cre...

Full description

Bibliographic Details
Main Authors: Fletcher, Mark D., Krumbholz, Katrin, de Boer, Jessica
Format: Article
Published: Springer 2016
Subjects:
Online Access:https://eprints.nottingham.ac.uk/36187/
_version_ 1848795239101235200
author Fletcher, Mark D.
Krumbholz, Katrin
de Boer, Jessica
author_facet Fletcher, Mark D.
Krumbholz, Katrin
de Boer, Jessica
author_sort Fletcher, Mark D.
building Nottingham Research Data Repository
collection Online Access
description The active cochlear mechanism amplifies responses to low-intensity sounds, compresses the range of input sound intensities to a smaller output range, and increases cochlear frequency selectivity. The gain of the active mechanism can be modulated by the medial olivocochlear (MOC) efferent system, creating the possibility of top-down control at the earliest level of auditory processing. In humans, MOC function has mostly been measured by the suppression of optoacoustic emissions (OAEs), typically as a result of MOC activation by a contralateral elicitor sound. The exact relationship between OAE suppression and cochlear gain reduction, however, remains unclear. Here, we measured the effect of a contralateral MOC elicitor on perceptual estimates of cochlear gain and compression, obtained using the established temporal masking curve (TMC) method. The measurements were taken at a signal frequency of 2 kHz and compared with measurements of click-evoked OAE suppression. The elicitor was a broadband noise, set to a sound pressure level of 54 dB to avoid triggering the middle ear muscle reflex. Despite its low level, the elicitor had a significant effect on the TMCs, consistent with a reduction in cochlear gain. The amount of gain reduction was estimated as 4.4 dB on average, corresponding to around 18 % of the without-elicitor gain. As a result, the compression exponent increased from 0.18 to 0.27.
first_indexed 2025-11-14T19:28:55Z
format Article
id nottingham-36187
institution University of Nottingham Malaysia Campus
institution_category Local University
last_indexed 2025-11-14T19:28:55Z
publishDate 2016
publisher Springer
recordtype eprints
repository_type Digital Repository
spelling nottingham-361872020-05-04T18:23:26Z https://eprints.nottingham.ac.uk/36187/ Effect of contralateral medial olivocochlear feedback on perceptual estimates of cochlear gain and compression Fletcher, Mark D. Krumbholz, Katrin de Boer, Jessica The active cochlear mechanism amplifies responses to low-intensity sounds, compresses the range of input sound intensities to a smaller output range, and increases cochlear frequency selectivity. The gain of the active mechanism can be modulated by the medial olivocochlear (MOC) efferent system, creating the possibility of top-down control at the earliest level of auditory processing. In humans, MOC function has mostly been measured by the suppression of optoacoustic emissions (OAEs), typically as a result of MOC activation by a contralateral elicitor sound. The exact relationship between OAE suppression and cochlear gain reduction, however, remains unclear. Here, we measured the effect of a contralateral MOC elicitor on perceptual estimates of cochlear gain and compression, obtained using the established temporal masking curve (TMC) method. The measurements were taken at a signal frequency of 2 kHz and compared with measurements of click-evoked OAE suppression. The elicitor was a broadband noise, set to a sound pressure level of 54 dB to avoid triggering the middle ear muscle reflex. Despite its low level, the elicitor had a significant effect on the TMCs, consistent with a reduction in cochlear gain. The amount of gain reduction was estimated as 4.4 dB on average, corresponding to around 18 % of the without-elicitor gain. As a result, the compression exponent increased from 0.18 to 0.27. Springer 2016-12-31 Article PeerReviewed Fletcher, Mark D., Krumbholz, Katrin and de Boer, Jessica (2016) Effect of contralateral medial olivocochlear feedback on perceptual estimates of cochlear gain and compression. Journal of the Association for Research in Otolaryngology, 17 (6). pp. 559-575. ISSN 1525-3961 medial olivocochlear reflex (MOCR); temporal masking curve (TMC); click-evoked otoacoustic emissions (CEOAEs); contralateral acoustic stimulation; cochlear amplification http://link.springer.com/article/10.1007/s10162-016-0574-8 doi:10.1007/s10162-016-0574-8 doi:10.1007/s10162-016-0574-8
spellingShingle medial olivocochlear reflex (MOCR); temporal masking curve (TMC); click-evoked otoacoustic emissions (CEOAEs); contralateral acoustic stimulation; cochlear amplification
Fletcher, Mark D.
Krumbholz, Katrin
de Boer, Jessica
Effect of contralateral medial olivocochlear feedback on perceptual estimates of cochlear gain and compression
title Effect of contralateral medial olivocochlear feedback on perceptual estimates of cochlear gain and compression
title_full Effect of contralateral medial olivocochlear feedback on perceptual estimates of cochlear gain and compression
title_fullStr Effect of contralateral medial olivocochlear feedback on perceptual estimates of cochlear gain and compression
title_full_unstemmed Effect of contralateral medial olivocochlear feedback on perceptual estimates of cochlear gain and compression
title_short Effect of contralateral medial olivocochlear feedback on perceptual estimates of cochlear gain and compression
title_sort effect of contralateral medial olivocochlear feedback on perceptual estimates of cochlear gain and compression
topic medial olivocochlear reflex (MOCR); temporal masking curve (TMC); click-evoked otoacoustic emissions (CEOAEs); contralateral acoustic stimulation; cochlear amplification
url https://eprints.nottingham.ac.uk/36187/
https://eprints.nottingham.ac.uk/36187/
https://eprints.nottingham.ac.uk/36187/