Overt and covert paths for sound in the auditory system of mammals

of the article “Overt and covert paths for sound in the auditory system of mammals”, by Bernard M. Auriol, Jérôme Béard, Jean-Marc Broto, Didier F. Descouens , Lise J.S. Durand, Frederick Garcia, Christian F. Gillieaux, Elizabeth G. Joiner, Bernard Libes, Robert Ruiz, and Claire Thalamas. (May 08, 2014) The consensus, according to which the transmission of sound from the tympanum to the Outer Hair Cells is solely mechanical, is problematic, especially with respect to high pitched sounds. We demonstrate that the collagenous fibers of the tympanum produce electric potentials synchronous to acoustic vibrations and that, contrary to expectations, their amplitude increases as the frequency of the vibration increases. These electrical potentials cannot be reduced to the cochlear microphonic. Moreover, the alteration of collagen as well as gap junctions between Deiters cells results in hypoacusis or deafness. The discovery of an electronic pathway, complementary to air and bone conduction has the potential for elucidating certain important as yet unexplained aspects of hearing with respect to cochlear amplification, otoacoustic emissions, and hypoacusis related to the deterioration of collagen or of gap-junctions. Thus, our findings have important implications for both theory and practice.