TY - JOUR
T1 - Spatial distribution of electrically induced high frequency vibration on basilar membrane
AU - Hu, Ning
AU - Nuttall, Alfred L.
AU - Ren, Tianying
N1 - Funding Information:
This work was supported by NIDCD Grants DC00141, DC04554 and VA RR&D Center Grants.
PY - 2005/4
Y1 - 2005/4
N2 - We reported that the electrically evoked basilar membrane (BM) vibration at frequencies above the best frequency (BF) showed a lowest BM velocity magnitude, called a "dip", in the velocity-frequency spectra, indicating a cancellation. In the present study, we measured the high frequency BM motion as functions of the longitudinal and radial locations. Measurements were taken at three longitudinal locations in the first turn and the hook region: 14.9, 15.8 and 16.8 mm from the apex, corresponding to the BFs of 17, 21.3 and 28.0 kHz calculated from Greenwood [J. Acoust. Soc. Am. 87, 2592], and at different radial locations across the width of the BM. It was found that the dip frequency (DF) varied with the longitudinal and radial locations. In the longitudinal direction, the average value of the DF was 49.6, 55.6 and 72.8 kHz, respectively. Thus, the longitudinal distribution of the high frequency BM vibration was correlated with the BF. In the radial direction, there was consistent variation of the response spectrum such that the dip was mainly evident in the pectinate zone of the BM. These results imply that the high frequency BM motion is related to mechanical properties of the cochlear partition, including the outer hair cells (OHCs) themselves. Data also indicate different vibration modes across the width of the organ of Corti.
AB - We reported that the electrically evoked basilar membrane (BM) vibration at frequencies above the best frequency (BF) showed a lowest BM velocity magnitude, called a "dip", in the velocity-frequency spectra, indicating a cancellation. In the present study, we measured the high frequency BM motion as functions of the longitudinal and radial locations. Measurements were taken at three longitudinal locations in the first turn and the hook region: 14.9, 15.8 and 16.8 mm from the apex, corresponding to the BFs of 17, 21.3 and 28.0 kHz calculated from Greenwood [J. Acoust. Soc. Am. 87, 2592], and at different radial locations across the width of the BM. It was found that the dip frequency (DF) varied with the longitudinal and radial locations. In the longitudinal direction, the average value of the DF was 49.6, 55.6 and 72.8 kHz, respectively. Thus, the longitudinal distribution of the high frequency BM vibration was correlated with the BF. In the radial direction, there was consistent variation of the response spectrum such that the dip was mainly evident in the pectinate zone of the BM. These results imply that the high frequency BM motion is related to mechanical properties of the cochlear partition, including the outer hair cells (OHCs) themselves. Data also indicate different vibration modes across the width of the organ of Corti.
KW - Basilar membrane
KW - Cochlea
KW - Electromotility
KW - Guinea pig
KW - High frequency
KW - Laser Doppler velocimeter
KW - Outer hair cells
KW - Vibration
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U2 - 10.1016/j.heares.2004.11.002
DO - 10.1016/j.heares.2004.11.002
M3 - Article
C2 - 15811697
AN - SCOPUS:16344388751
SN - 0378-5955
VL - 202
SP - 35
EP - 46
JO - Hearing Research
JF - Hearing Research
IS - 1-2
ER -