Subject: Re: cochlear discussions From: Antony Locke <A.Locke(at)SOTON.AC.UK> Date: Tue, 18 Jul 2000 12:10:39 +0100Andrew, Andrew Bell wrote: >This is just the point of the recent discussion on this list in which I gave >a positive answer to Antony Locke's question of whether the traveling wave >was "an epiphenomenon". I suggested (in my post of 28/6) that, in a sense, a >graded delay in a bank of tuned resonators can be seen as a TW, making the >TW epiphenomenal -- because it doesn't carry energy. However, in Jont >Allen's post in reply (29/6), he pointed out that the TW also embodies >additional, theoretically based, hydraulic elements that couple to the >basilar membrane and carry energy from one partition element to the next. So >we have ended up with two different (incompatible) mechanisms distinguished >by how energy propagates in the cochlea, as well as by what the >frequency-analysing elements are. No, we haven't "ended up with two different (incompatible) mechanisms distinguished by how energy propagates in the cochlea". Re-read my emails. In my original posting I stated that "the slow wave is a hydromechanical wave that is dependent upon the interaction of the CP [cochlear partition] and fluid within the scalae; it is referred to as the travelling wave." You did not satisfactorily answer my two original questions concerned with energy flow at the most basic level of description. Jont Allen explained to you that a bank of tuned resonators is not a physically meaningful model of energy flow in the cochlea. It was politely suggested that you submit an explanation of your model to JASA. It is difficult to follow and then counter a proposed model when it has not been stated in a logical fashion. After hundreds of words in your emails, I conclude that : 1) You do not understand the travelling wave model of energy propagation in the cochlea. 2) You propose an alternative model that i) ignores established anatomical/physiological/mechanical findings and ii) requires numerous assumptions about the properties of the cochlear partition, all of which have not been observed. IMO, you do a disservice to science by stating there is an incompatibility in the current thinking on energy flow within the cochlea at the most basic level of description. Antony Locke