A Component of Stimulus-Frequency Otoacoustic Emissions Evoked due to Perturbation of Nonlinear Force in a Cochlear Model

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21230%2F24%3A00374888" target="_blank" >RIV/68407700:21230/24:00374888 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/68407700:21340/24:00374888

Výsledek na webu

<a href="https://doi.org/10.1063/5.0189467" target="_blank" >https://doi.org/10.1063/5.0189467</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1063/5.0189467" target="_blank" >10.1063/5.0189467</a>

Jazyk výsledku

angličtina

Název v původním jazyce

A Component of Stimulus-Frequency Otoacoustic Emissions Evoked due to Perturbation of Nonlinear Force in a Cochlear Model

Popis výsledku v původním jazyce

Stimulus-frequency otoacoustic emissions (SFOAEs) are evoked by a single tone presented into the ear. The emissions are generated by reflection of a forward traveling wave (TW) on localized irregularities in the impedance along the basilar membrane (BM). The strongest wavelets are reflected from the place where the TW reaches its largest amplitude. Since the irregularities are localized in fixed places along the basilar membrane, the latency of the SFOAE phase can be used to estimate delay of cochlear filters. We used an iterative approach of Shera et al. [JASA (2005) 118:287-313] to obtain an analytical solution for SFOAEs in a nonlinear two-dimensional cochlear model. The solution allowed for decomposition of a reflection component and a component due to perturbation of the nonlinear force. The nonlinear force which in the smooth cochlea may reflect the forward TW backwards [Talmadge et al., JASA (2000) 108, 2911-2931], is perturbed due to irregularities. The perturbed nonlinear force in the model generates an SFOAE component with latency comparable with the latency of the component due to reflection. This means that although the component is evoked due to nonlinear force, it has a comparable (long) latency to the SFOAE component due to reflection. The amplitude of this component due to perturbation of the nonlinear force grows as the amplitude of irregularities increases. In addition, the component amplitude also grows with the tone intensity. The growth is determined by the amplitude of the nonlinear force. It is almost cubic at the lowest intensities and quickly saturates at levels above about 40 dB SPL (the intensity is determined by the position of the compressive nonlinearity in the input/output function of the basilar membrane displacement). An interesting result is that the nonlinear component partly cancels the reflection component because its phase is shifted by approximately 0.5 cycles, independent of stimulus intensity and frequency. As the level increases, the component due to perturbation reaches an amplitude comparable to the component due to coherent reflection, especially in the portions of SFOAEs with the longest latencies. The destructive interference between the components due to perturbation of the nonlinear force and coherent reflection emphasizes shorter latency wavelets in the overall SFOAEs as stimulus intensity increases and contributes to the saturation of SFOAE amplitude reported, for example, in human experimental data of Abdala and Kalluri [JASA (2017) 142, 812-824].

Název v anglickém jazyce

A Component of Stimulus-Frequency Otoacoustic Emissions Evoked due to Perturbation of Nonlinear Force in a Cochlear Model

Popis výsledku anglicky

Stimulus-frequency otoacoustic emissions (SFOAEs) are evoked by a single tone presented into the ear. The emissions are generated by reflection of a forward traveling wave (TW) on localized irregularities in the impedance along the basilar membrane (BM). The strongest wavelets are reflected from the place where the TW reaches its largest amplitude. Since the irregularities are localized in fixed places along the basilar membrane, the latency of the SFOAE phase can be used to estimate delay of cochlear filters. We used an iterative approach of Shera et al. [JASA (2005) 118:287-313] to obtain an analytical solution for SFOAEs in a nonlinear two-dimensional cochlear model. The solution allowed for decomposition of a reflection component and a component due to perturbation of the nonlinear force. The nonlinear force which in the smooth cochlea may reflect the forward TW backwards [Talmadge et al., JASA (2000) 108, 2911-2931], is perturbed due to irregularities. The perturbed nonlinear force in the model generates an SFOAE component with latency comparable with the latency of the component due to reflection. This means that although the component is evoked due to nonlinear force, it has a comparable (long) latency to the SFOAE component due to reflection. The amplitude of this component due to perturbation of the nonlinear force grows as the amplitude of irregularities increases. In addition, the component amplitude also grows with the tone intensity. The growth is determined by the amplitude of the nonlinear force. It is almost cubic at the lowest intensities and quickly saturates at levels above about 40 dB SPL (the intensity is determined by the position of the compressive nonlinearity in the input/output function of the basilar membrane displacement). An interesting result is that the nonlinear component partly cancels the reflection component because its phase is shifted by approximately 0.5 cycles, independent of stimulus intensity and frequency. As the level increases, the component due to perturbation reaches an amplitude comparable to the component due to coherent reflection, especially in the portions of SFOAEs with the longest latencies. The destructive interference between the components due to perturbation of the nonlinear force and coherent reflection emphasizes shorter latency wavelets in the overall SFOAEs as stimulus intensity increases and contributes to the saturation of SFOAE amplitude reported, for example, in human experimental data of Abdala and Kalluri [JASA (2017) 142, 812-824].

Druh

D - Stať ve sborníku

CEP obor

—

OECD FORD obor

10307 - Acoustics

Projekt

—

Návaznosti

S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2024

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

Nonlinearity and Hearing: Advances in Theory and Experiment - Proceedings of the 14th International Mechanics of Hearing Workshop

ISBN

9780735448445

ISSN

1551-7616

e-ISSN

1551-7616

Počet stran výsledku

7

Strana od-do

"030014-1"-"030014-7"

Název nakladatele

American Institute of Physics

Místo vydání

New York

Místo konání akce

Helsingør

Datum konání akce

24. 7. 2022

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

001226934800026