Abstract
The response of 17 primary auditory nerve fibers in the American bullfrog (Rana catesbeiana) to acoustic noise stimulation of the tympanic membrane was recorded. For each fiber, the first- and second-order Wiener kernels, k(1)(tau(1)) and k(2)(tau(1),tau(2)), were computed by cross correlation of the stimulus and the response. The kernels revealed amplitude and phase characteristics of auditory filters of both phase-locking and non-phase-locking fibers. Wiener kernels of high- and midfrequency fibers (best frequency, BF>500 Hz), implied a simple sandwich model, consisting of a cascade of a linear bandpass filter, a static nonlinearity, a linear low-pass filter, and a spike generator. The bandpass filter was at least of order 7, and had a linear phase response, for both the high- and the midfrequency fibers. Averaged across fibers, filter order 2, and cutoff frequency 451 Hz for the second filter in the model was observed. The responses of low-frequency fibers (BF<500 Hz) could not be fit with the sandwich model, because the Fourier transform K-2(f(1),f(2)) of the second-order Wiener kernel showed significant components at off-diagonal frequencies f(1) not equal+/-f(2). The presence of these off-diagonal components shows that, in addition to the phase and gain characteristics of auditory filters, the Wiener kernel analysis reveals nonlinear two-tone interactions.
Original language | English |
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Pages (from-to) | 904-919 |
Number of pages | 16 |
Journal | Journal of the Acoustical Society of America |
Volume | 95 |
Issue number | 2 |
DOIs | |
Publication status | Published - Feb-1994 |
Keywords
- PERIPHERAL AUDITORY-SYSTEM
- NERVE-FIBERS
- RANA-CATESBEIANA
- SYNCHRONIZATION
- SENSITIVITIES
- SELECTIVITY
- RESPONSES
- NEURONS
- PAPILLA