Abstract
Basilar-membrane responses to white Gaussian noise were recorded using laser velocimetry at basal sites of the chinchilla cochlea with characteristic frequencies near 10 kHz and first-order Wiener kernels were computed by cross correlation of the stimuli and the responses. The presence or absence of minimum-phase behavior was explored by fitting the kernels with discrete linear filters with rational transfer functions. Excellent fits to the kernels were obtained with filters with transfer functions including zeroes located outside the unit circle, implying nonminimum-phase behavior. These filters accurately predicted basilar-membrane responses to other noise stimuli presented at the same level as the stimulus for the kernel computation. Fits with all-pole and other minimum-phase discrete filters were inferior to fits with nonminimum-phase filters. Minimum-phase functions predicted from the amplitude functions of the Wiener kernels by Hilbert transforms were different from the measured phase curves. These results, which suggest that basilar-membrane responses do not have the minimum-phase property, challenge the validity of models of cochlear processing, which incorporate minimum-phase behavior.
Original language | English (US) |
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Article number | 5483155 |
Pages (from-to) | 1456-1465 |
Number of pages | 10 |
Journal | IEEE Transactions on Biomedical Engineering |
Volume | 58 |
Issue number | 5 |
DOIs | |
State | Published - May 2011 |
Funding
Manuscript received March 15, 2010; revised May 1, 2010; accepted May 28, 2010. Date of publication June 10, 2010; date of current version April 20, 2011. This work was supported in part by the National Institutes of Health under Grant DC-000419. Asterisk indicates corresponding author.
Keywords
- Autoregressive moving-average (ARMA) modeling
- Hilbert transform
- Wiener kernels
- basilar membrane (BM)
- cochlea
- minimum phase
ASJC Scopus subject areas
- Biomedical Engineering