Details

Autor(en) / Beteiligte

• Siegel, Jonathan H.
• Cerka, Amanda J.
• Recio-Spinoso, Alberto
• Temchin, Andrei N.
• van Dijk, Pim
• Ruggero, Mario A.

Titel

Delays of stimulus-frequency otoacoustic emissions and cochlear vibrations contradict the theory of coherent reflection filtering

Ist Teil von

• The Journal of the Acoustical Society of America, 2005-10, Vol.118 (4), p.2434-2443

Ort / Verlag

Woodbury, NY: Acoustical Society of America

Erscheinungsjahr

2005

Link zum Volltext

Quelle

AIP Journals Complete

Beschreibungen/Notizen

• When stimulated by tones, the ear appears to emit tones of its own, stimulus-frequency otoacoustic emissions (SFOAEs). SFOAEs were measured in 17 chinchillas and their group delays were compared with a place map of basilar-membrane vibration group delays measured at the characteristic frequency. The map is based on Wiener-kernel analysis of responses to noise of auditory-nerve fibers corroborated by measurements of vibrations at several basilar-membrane sites. SFOAE group delays were similar to, or shorter than, basilar-membrane group delays for frequencies > 4 kHz and < 4 kHz , respectively. Such short delays contradict the generally accepted "theory of coherent reflection filtering" [ Zweig and Shera , J. Acoust. Soc. Am. 98 , 2018-2047 ( 1995 ) ], which predicts that the group delays of SFOAEs evoked by low-level tones approximately equal twice the basilar-membrane group delays. The results for frequencies higher than 4 kHz are compatible with hypotheses of SFOAE propagation to the stapes via acoustic waves or fluid coupling, or via reverse basilar membrane traveling waves with speeds corresponding to the signal-front delays, rather than the group delays, of the forward waves. The results for frequencies lower than 4 kHz cannot be explained by hypotheses based on waves propagating to and from their characteristic places in the cochlea.