Stimulus-frequency, transient-evoked, and distortion product otoacoustic emissions (OAEs) have been measured in eight normal-hearing human ears over a wide stimulus level range, with high spectral resolution. The single-reflection component of the response was isolated using time-frequency filtering, and its average delay was measured as a function of frequency and stimulus level. The apical-basal transition was studied by fitting the average delay of the filtered single-reflection OAEs, expressed in number of cycles, to a three-slope power-law function with two knot frequencies. The results show that the scale-invariant prediction of constant dimensionless delay approximately holds only over a narrow intermediate frequency range (1-2.5 kHz). Below 1 kHz, and, to some extent, above 2.5 kHz, the dimensionless delay increases with frequency, at all stimulus levels. Comparison with the numerical simulations of a delayed-stiffness active cochlear model show that the increase of tuning with frequency reported by behavioral experiments only partly explains this result. The low-frequency scaling symmetry breaking associated with the deviation of the Greenwood tonotopic map from a pure exponential function is also insufficient to explain the steep low-frequency increase of the OAE delay. Other sources of symmetry breaking, not included in the model, could therefore play a role.
Moleti, A., Pistilli, D., & Sisto, R. (2017). Evidence for apical-basal transition in the delay of the reflection components of otoacoustic emissions. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA, 141(1), 116-126 [10.1121/1.4973866].
|Tipologia:||Articolo su rivista|
|Citazione:||Moleti, A., Pistilli, D., & Sisto, R. (2017). Evidence for apical-basal transition in the delay of the reflection components of otoacoustic emissions. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA, 141(1), 116-126 [10.1121/1.4973866].|
|Settore Scientifico Disciplinare:||Settore FIS/07 - Fisica Applicata(Beni Culturali, Ambientali, Biol.e Medicin)|
|Revisione (peer review):||Esperti anonimi|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1121/1.4973866|
|Stato di pubblicazione:||Pubblicato|
|Data di pubblicazione:||2017|
|Titolo:||Evidence for apical-basal transition in the delay of the reflection components of otoacoustic emissions|
|Autori:||Moleti, A; Pistilli, D; Sisto, R|
|Appare nelle tipologie:||01 - Articolo su rivista|