 |
Workshop on the Auditory Basis of Speech PerceptionKeele University, UK |
 |
|
Workshop on the Auditory Basis of Speech PerceptionKeele University, UK |
|
We present a phenomenological filter model that simulates the non-linear characteristics of basilar membrane filtering in mammalian cochlea. Cochlear non-linearity has already been shown to have important functions in the processing of complex stimuli by mammals. The Dual Resonance Non- linearity (DRNL) model closely simulates empirical results obtained from mechanical cochlear experiments. This purely passive model demonstrates a centre frequency shift, and filter width increase with a rise in stimulus level. It also reproduces two-tone suppression, combination tone distortion products and other data dependent upon cochlear non-linearity. The DRNL model is a composite filter consisting of two parallel filter paths: one linear and the other containing a compressive non-linearity. The model parameters were optimised at best frequencies of 0.3, 8 and 18 kHz, using simulated annealing. The model was incorporated into an auditory simulation computing library (LUTEar) and used to demonstrate non-linear auditory phenomena.
Bibliographic reference. O'Mard, L. P. / Meddis, R. (1996): "A computational model of non-linear auditory frequency selectivity", In ABSP-1996, 114-119.