Talk:Basilar membrane

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I removed this section:

The benefit that animals have from this third function is still a matter of research. The hypothesis of von Békésy that it would provide frequency selectivity for the hair cells turned out to be in error. Research results of recent decades showed that frequency selectivity in hearing remains intact even with an immobilized basilar membrane [1]. Therefore one had to conclude that also mammals, as all other land vertebrates, hear frequency-selectively due to intrinsically tuned hair cells. This conclusion was later confirmed by an extensive study where a large-scale pharmacological knockout of one type of hair cells resulted in a complete loss of frequency-selective hearing, even though the basilar membrane had remained fully functional [2].

because the cited articles do not support the gist of the paragraph. The results of article two and the role of outer hair cells in general (which was the true mystery of von Bekesy's results) do need to be incorporated into this article. But it is the role of outer hair cells to augment the resonance of the basilar membrane that probably leads to hearing loss in bats without outer hair cells, not special frequency tuning of the outer hair cells. The first article doesn't speak to the issues of the removed paragraph. --Chinasaur 01:55, 22 March 2006 (UTC)

Dear Chinasaur, the report by Nageris et al. (1996) clearly presents data in the text and in the figures that demand the above stated conclusion. You also misunderstood the report by Kössl et al. (2000). It is not true that the basilar membrane (BM) must move, before the stereocilia can move. Nilsen and Russell (1999) showed in highly sophisticated experiments that the BM on its own (post mortem) starts moving above noise (displacement of 0.5 nm) at levels > 65 dB SPL (their Fig.5). This clearly shows that the BM on its own cannot carry any sound signal at low sound levels. The cochlear fluids, however, can. It is therefore necessary to assume that they provide the adequate stimulus for the stereocilia in all vertebrates. See also the replication of these results in Nilsen and Russell (2000). I will therefore re-install the section that you deleted, and then extend the reference list. DiMare 14:34, 30 June 2006 (UTC)