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Re: A new paradigm?(On pitch and periodicity (was "correction to post"))

Since I only subscribe to the daily digest, apologies if this post is superfluous or has already been pre- and superseded by something more helpful.

> Richard F. Lyon <DickLyon@xxxxxxx> wrote:

My impression is that "transmission line models" is too tied to
one-dimensional or long-wave approximations. Am I wrong? Is it the
case that you can make a 1D electrical transmission-line analog of a
2D or 3D hydrodynamic traveling-wave system? Or do you mean to
include 2D electrical analogs in what you call transmission-line
models? We just need to be clear what the scope of your preferred
term is.

More credit to Diek Duifhuis is due here. In a 1988 conference paper [in Edelman et al (eds) Auditory Function: Neurological Bases for Hearing] he introduced an averaging procedure that allows the reduction of a 2- or 3D model to an equivalent 1D transmission line. (Obviously, it's only "equivalent" for some purposes.) Talmadge, Tubis, and I used this approach in our study of wave scattering in a 2D cochlea [J Acoust Soc Am 2005; 118:287–313]. Our study was motivated, in part, by Zwislocki's claims [1983 Hear Res 9, 103–111] that wave scattering cannot occur in the "short-wave" region near the peak of the traveling wave. It turns out that Zwislocki, who introduced an alternate but flawed dimensional-reduction procedure, made some technical errors that invalidated his result. More recently, I believe that Steve Elliot and colleagues at ISVR have a forthcoming paper on dimensional-reduction issues.

... The experiments you [Heerens] are
refering to on retrograde waves and the delays of OAEs also fall in this
category. I wish I had the time to show what the outcome of a
transmission line model would be on simulations of these experiments. I
am sure they would show agreement with the experiments instead of
agreement with the criticism. Please don't take a lack of proof as a
proof of lack.
This exact question was looked at in a paper at the 2011 Mechanics of
Hearing meeting, with the result that simulations using the traveling
wave models do agree with Ren's observations on OAEs. The resulting
book isn't out yet, and I'm not able to spot the right paper on the
web site right now, but I'll look for it; maybe someone else will
recall which one I refer to.

There were several papers on this topic at MoH2011, including those by de Boer et al, Sisto et al, and Vestesnik and Gummer. All are included in the forthcoming proceedings book [What Fire is in Mine Ears: Progress in Auditory Biomechanics, now in final production at AIP Press and also soon to be available online (open access)].

The MoH2011 papers are just the latest in a series of papers that show that conventional, active transmission-line models can readily reproduce Ren et al.'s findings. The first that I know of was presented at MoH2005 [Shera, Talmadge, and Tubis in Nuttall et al (eds) Auditory Mechanisms: Processes and Models]. At MoH2008, Zhang and Mountain had a nice paper addressing the issue [in Cooper and Kemp (eds) Concepts and Challenges in the Biophysics of Hearing]. There have also been several papers in JASA, most recently by Sisto et al [2011; 129:3141–3152]. The bottom line, as others have emphasized on this list, is that Ren et al.'s results are not compelling evidence for the absence of reverse traveling waves or the failure of conventional models.