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Re: Traveling waves or resonance?



Richard F. Lyon wrote:

> I accept
> that we have at least a four-way split over how to interpret Ren's
> experiment.  I'm not saying that any of you is wrong, but that
> Ren's data are also very much consistent with the traveling wave
> models.  Furthermore, those models can accommodate local resonances
> that interact with and determine the wave.  So I don't see why we need
> such a dichotomy between the approaches, when they can be integrated.

Martin already subordinates TW but ascribes CFs to the properties of OHCs.
Andrew shares my view that TW is just an epiphenomenon. A first reason
to do so is the lack of essential energy transmission from base to apex. An
additional reasons for me is the fit of my real-valued spectrogram to known data
without any problem and without any tweaking.
Sophisticated wave equations are a bit too flexible as to be trustworthy.
Moreover, speculations on reflected waves and also the argument of phase
accumulation have proven untenable. Otherwise, I would be ready to interpret my
Fig. 3 in M277 in terms of a TW-model. The epiphenomenal travel inside a
standing envelope is well to be seen in this figure. Look at the 3 kHz component
showing frequency chirping up with elapsed time. This effect continuously
broadens bandwidth as a precondition for subsequent cepstral analysis. Do
TW-models exhibit the same?
So my spectrogram would be able to replace the subordinated TW in combination
with Martin's OHC-hypothesis. Alternatively, it could incorporate any good
mechanical or electromechanical model of cochlea.

I only expect much additional insight from models that more quantitatively
mimick the definitely more involved processes inside cochlea. So far neither the
radial coupling between the rows nor the tilted structure of OHC-bundles has
been taken into account. Also, Nelson's notch, and many other phenomena are
still to be implemented. Even simple lever models might perform better than blind
application of differential equations with more input parameters than one can
reasonably handle.

Anticipating ongoing distrust against my unaccustomed mathematical results, I
would like to inform you that I got unexpected support concerning a marginal but
fundamental issue: http://www.fh-augsburg.de/~mueckenh/

Eckard