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Re: HC selectivity ... was Re: Physiological models of cochlea activity - alternatives to the travelling wave

Quoting Matt Flax <flatmax@xxxxxxxx>:

Hi Eckard,

Can you please link me to your model, I would like to include it on the


Hi matt,

Since you are on the AUDITORY list for many years, you should know several links. I hope, they are still available.

My last paper: "A Still Valid Argument by Ritz" has just been submitted.

My paper "Adaptation of Spectral Analysis to Reality" was recently amended by Robert Fritzius. The new version is hopefully still available at
The original version is available from IEEE:

My paper
"Alternatives to the traditional spectrogram: Real-valued spectrogram and
cepstrum-like autocorrelation" is on the CD of 23th TMT 2004 Leipzig: VDT International Audio Convention. It is also hopefully still available via

http://iesk.et.uni-magdeburg.de/~blumsche/M275.html "Comment on 'Paradoxial Cochlea' "
provides the link to

Let me clarify that my primary concern was not to create a model of cochlea.
Dealing with thwe many notorious imperfections of spectrograms, I finally found out a spectral analysis that is free of the usual burden of an arbitrarily chosen point of reference.

Its agreement with results of modeling is good. Its agreement with physiological data is even better. I consider the speed of traveling wave a weak point in all models which are based on wave equations. I agree with Martin Braun and others that all longitudinal wave models do not have anything to do with what is really going on in cochlea. Of course BM and TM, OHCs and IHCs, afferents and efferents, nois and spontaneous activity, LSR and HSR fibers, etc. form a highly efficient and so far just partially understood system.
Peculiarities with animals should open our eyes and indicate that cochlear mechanics does definitely not work as believed. I recall Jont Allen confessing being shocked for a moment when he was pointed to something like a fovea. However, he perhaps forgot the shock and returned to the agenda.

Let me repeat: My purified from double redundancy cosine spectrogram automatically yields what is still believed a wave phenomenon: propagating as well as rolling on the spot traveling waves depending on the sign of stimulus.
I vaguely recall an ARO paper that dealt with the question how strong the longitudinal coupling along BM is and arrived at the conclusion that it can be neglected.

Obviously, all research in cochlear mechanics so far is on the wrong track, and it will presumably not yield anything of value.

What about the picometer issue. Yes, this is less than the diameter of the hydrogen atom, the smallest one. I share the idea that active response to noise makes possible what seems to be a miracle to physicist.

Eckard Blumschein

On Mon, Oct 01, 2007 at 07:35:03PM +0200, Eckard Blumschein wrote:
Quoting Martin Braun <nombraun@xxxxxxxxx>:

You need meta-knowledge to be able to asses if a model is correct and
useful. In science this meta-knowledge is: All Relevant Data.

Dear Martin,

Exactly, almost ten years ago Jont Allen confessed: No model fits all data.
I would like to mock: The model by Lighthill alias Lichtenberg was too good
as to be honest. The Nobel price was awarded to a compatriot of those who
get famous in connection with Berlin: v. Neumann, Wigner, Szilard.  The
laureat just selected the idea of traveling wave. In order to deny that
this brought shame on the price, reigning referees passed every stupid
trial to defend the wrong idea of energy transfer from the base to the apex
of the cochlea as the mechanism of the traveling wave.

For example, because a wealth of data proves that the basilar membrane
BM) in the mammalian cochlea does not respond to sound levels below
about 60 dB, once the outer hairs cells (OHC) have been made temporally
or ultimately non-functional, I reject all models of cochlear mechanics
that state that the BM triggers the OHCs at ALL sound levels. However
beautiful these models are!

Why not taking into account the possibility that OHCs respond to noise and this lowers the threshold for the combination BM + OHC by 60 bB? Such getting into resonance would explain the additional delay at low SPL. It is just a guess of mine: Mammal hearing is superior due to higher frequencies. I guess: The exceptional high frequencies of bats, dolphines and whales are not coupled with high sensitivity. Calls of bats are loud enough. Water alllows for higher SPL. Most likely, mechanics functions up to higher frequencies.

False models of mammalian cochlear functions have seriously impeded
basic research and medical research for decades - and up to this very

I agree with you that we do not need fundamentally wrong models if both types of traveling waves are just epiphenomena of local resonance, the propagating one and also the narrow one rolling on the spot. Do you have any objection against my cosine spectrogram as the only model of hearing so far that resembles cochlear function in all essentials: - highest possible resolution in terms of time and frequency simultaneously - local and propagating traveling waves to be seen - absolute agreement with delay data without tweaking at will - plausible distinction between positive and negative clicks

I remember that you are insusceptible for ideas other tha yours. Tell me
how outer hair cells alone could made the distinction.


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