Subject: Re: HC selectivity ... was Re: Physiological models of cochlea activity - alternatives to the travelling wave From: Eckard Blumschein <Eckard.Blumschein@xxxxxxxx> Date: Mon, 1 Oct 2007 19:35:03 +0200 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>Quoting Martin Braun <nombraun@xxxxxxxx>: > 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 > day. 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. Regards, Eckard