On Fri, May 21, 2010 at 1:33 PM, Bastian Epp
<Bastian.Epp@xxxxxxxxxxxxxxxx> wrote:
Dear list!
As the comparison and evaluation of cochlear models is exactly what bothered my during the last year (or so), I think I want to share my points:
In general, it is very interesting to compare and to evaluate models of the cochlea...even though that is sometimes quite hard due to different approaches.
I agree with the view, that one way to evaluate cochlear models is to look at their performance to account for many different datasets (physical (OAE), physiological(I/O) and even psychoacoustical) simultaneously with a "decent" amount of fixed parameters....but especially for the psychoacoustic paradigms, the potential for arguing starts at the metric which is evaluated to account for the data. So maybe one should start with physiological data and/or use very simple (and still feasable) approaches for psychoacoustics. Some ideas as a starter:
Excitation patterns:
Evaluation of the shape of the excitation pattern (slopes basal/apical, Q-factor, ...) in a panoramic view (whole cochlea) and at a single place for different frequencies (place-fixed view).
I/O-functions:
Evaluation of the response of the model at a fixed place for different levels of the same frequency
OAE:
Propagation of the cochlear activity through a simple model of the middle ear (which should be comparable as long as the used middle ear is linear).
Phase-issues with evoked (e.g. CEOAE) emissions?
Two-tone suppression:
Here it's getting neccessary to define the metric which is evaluated, but there should be the phenomenon of a nonlinear interaction of two tones...independently of the analysis which is applied.
...
All these measures should be relatively robust against absolute scaling and hence be comparable and (if the model is supposed to be "realistic" in one sense or the other) in line with data.
I see a big chance in that, since different models account (and are developped for) different aspects of cochlear functioning, and all reflect a special case of THE cochlea which was implemented by nature.
We did the things mentioned above (and some more) using the Duifhuis-Transmission line in a modifed form. I would be happy to share ideas with anybody who is also interested. We are also preparing a manuscript and I am also happy to share that as soon as it is in a readable form. (BTW: Thx Jon for sharing the manuscript, nice collection of data and a good start for discussions....)
If anybody read the message until here: Sorry for the length.
Best from Oldenburg
BAstian