Rights statement: Copyright © 2014 Yasin et al. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution andreproduction in any medium providedthatthe original work is properly attributed.
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Final published version
Licence: CC BY
Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Effect of human auditory efferent feedback on cochlear gain and compression
AU - Yasin, Ifat
AU - Drga, Vit
AU - Plack, Christopher J.
N1 - Copyright © 2014 Yasin et al. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution andreproduction in any medium providedthatthe original work is properly attributed.
PY - 2014/11/12
Y1 - 2014/11/12
N2 - The manunalian auditory system includes a brainstem-mediated efferent pathway from the superior olivary complex by way of the medial olivocochlear system, which reduces the cochlear response to sound (Warr and Guinan, 1979; Liberman et al., 1996). The human medial olivocochlear response has an onset delay of between 25 and 40 ms and rise and decay constants in the region of 280 and 160 ms, respectively (Backus and Guinan, 2006). Physiological studies with nonhuman mammals indicate that onset and decay characteristics of efferent activation are dependent on the temporal and level characteristics of the auditory stimulus (Bacon and Smith, 1991; Guinan and Stankovic, 1996). This study uses a novel psychoacoustical masking technique using a precursor sound to obtain a measure of the efferent effect in humans. This technique avoids confounds currently associated with other psychoacoustical measures. Both temporal and level dependency of the efferent effect was measured, providing a comprehensive measure of the effect of human auditory efferents on cochlear gain and compression. Results indicate that a precursor (>20 dB SPL) induced efferent activation, resulting in a decrease in both maximum gain and maximum compression, with linearization of the compressive function for input sound levels between 50 and 70 dB SPL. Estimated gain decreased as precursor level increased, and increased as the silent interval between the precursor and combined masker-signal stimulus increased, consistent with a decay of the efferent effect Human auditory efferent activation linearizes the cochlear response for mid-level sounds while reducing maximum gain.
AB - The manunalian auditory system includes a brainstem-mediated efferent pathway from the superior olivary complex by way of the medial olivocochlear system, which reduces the cochlear response to sound (Warr and Guinan, 1979; Liberman et al., 1996). The human medial olivocochlear response has an onset delay of between 25 and 40 ms and rise and decay constants in the region of 280 and 160 ms, respectively (Backus and Guinan, 2006). Physiological studies with nonhuman mammals indicate that onset and decay characteristics of efferent activation are dependent on the temporal and level characteristics of the auditory stimulus (Bacon and Smith, 1991; Guinan and Stankovic, 1996). This study uses a novel psychoacoustical masking technique using a precursor sound to obtain a measure of the efferent effect in humans. This technique avoids confounds currently associated with other psychoacoustical measures. Both temporal and level dependency of the efferent effect was measured, providing a comprehensive measure of the effect of human auditory efferents on cochlear gain and compression. Results indicate that a precursor (>20 dB SPL) induced efferent activation, resulting in a decrease in both maximum gain and maximum compression, with linearization of the compressive function for input sound levels between 50 and 70 dB SPL. Estimated gain decreased as precursor level increased, and increased as the silent interval between the precursor and combined masker-signal stimulus increased, consistent with a decay of the efferent effect Human auditory efferent activation linearizes the cochlear response for mid-level sounds while reducing maximum gain.
KW - cochlear
KW - compression
KW - efferent
KW - gain
KW - masking
KW - neural
KW - BASILAR-MEMBRANE NONLINEARITY
KW - CROSSED OLIVOCOCHLEAR BUNDLE
KW - IMPAIRED HEARING
KW - ELECTRICAL-STIMULATION
KW - FREQUENCY-SELECTIVITY
KW - OTOACOUSTIC EMISSION
KW - PERIPHERAL GAIN
KW - NERVE RESPONSE
KW - NOTCHED-NOISE
KW - TIME-COURSE
U2 - 10.1523/JNEUROSCI.1043-14.2014
DO - 10.1523/JNEUROSCI.1043-14.2014
M3 - Journal article
VL - 34
SP - 15319
EP - 15326
JO - Journal of Neuroscience
JF - Journal of Neuroscience
SN - 0270-6474
IS - 46
ER -