Subject: Re: A question on Bekesy. From: "reinifrosch@xxxxxxxx" <reinifrosch@xxxxxxxx> Date: Sat, 20 Mar 2010 11:58:40 +0000 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>David, What was the material in the cochlear duct that Bekesy repeatedly removed from the basilar membrane "with a fine brush" ? Today I re-consulted the review "Structure of the Mammalian Cochlea" by the late Norma Slepecki (1996), in the book "The Cochlea", Dallos et al., Eds., Springer, New York. If one looks at her Fig. 2.2, it appears possible that the mentioned material was the Claudius cells and the Hensen cells. In her Section 2.5.1, she wrote that the Hensen cells "[...] contain no filament or tubule bundles." In the Hensen cells there are "lipid droplets, which glisten like pearls". The Claudius cells resemble the Hensen cells. The agar that you mentioned yesterday may have played a role, however, in the BM stiffness measurements presented in Bekesy's Fig. 11-73. The helicotrema was closed with agar (so that a static pressure difference across the BM could be applied). That agar may have increased the BM stiffness near the apex. Reinhart. ----Ursprüngliche Nachricht------------------- Von: dcm@xxxxxxxx Datum: 19.03.2010 21:07 An: <reinifrosch@xxxxxxxx> Kopie: <AUDITORY@xxxxxxxx> Betreff: Re: A question on Békésy. If your real interest is the basilar membrane stiffness gradient, then I would take Fig. 11-73 on face value. [...] ----------------------------------------------------------- Reinhart Frosch, Dr. phil. nat., r. PSI and ETH Zurich, Sommerhaldenstr. 5B, CH-5200 Brugg. Phone: 0041 56 441 77 72. Mobile: 0041 79 754 30 32. E-mail: reinifrosch@xxxxxxxx .