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



Dear List,


In this thread:  “A new paradigm?(On pitch and periodicity ..)” the 
original start of all this  was the question of Nedra Floyd-Pautler about 
auditory illusions in relation to hearing aids.
But it was the comment of Randy Randhawa addressed to her with the 
following content:

In my opinion the most enduring (over 200 years) of all 
auditory "illusions" is what has been called the "missing fundamental". The 
fact that this has not been satisfactorily resolved by the tortured use of 
existing signal processing techniques leads some, including yours truly, to 
believe that the auditory system has figured out a unique way to do 
frequency analysis and to meet the dictum in biology that "form follows 
function". Taking into account where we are and the discussions that take 
place, e.g. this forum, it is interesting that there has been no discussion 
as to why the cochlear has the shape it does. Therefore some experimental 
phenomenon that we may call as an illusion, could have a very natural 
consequence of how frequency analysis is done. One is lead to believe that 
we are truly very far from understanding how the auditory system works and 
therefore hearing aid designs are a bit of a hoax foisted on 
the "proletariat". Sorry if I sound a bit harsh, but I think it is time 
people recognized that the emperor has not clothes.

And sorry for those who have other ideas, I completely agree with Randy’s 
remarks here above. And I have reasons for this opinion.

Although not being an auditory expert, but having an academic applied 
physics background I have studied already for more than ten years the 
functionality of the mammalian hearing sense.
Together with ENT MD J. Alexander de Ru I have recently published a booklet 
with the following title:

Applying Physics Makes Auditory Sense

With subtitle:
A new paradigm in hearing

This booklet describes in the first chapter – Introduction – the objections 
we have against a number of existing hypotheses, simply because they are at 
variance with general laws of physics.

In the second chapter – The new hypothesis – we describe how based on our 
findings the mammalian hearing sense can function in such a way that it is 
on the one hand in full agreement with the rules and laws of general 
physics and mechanics and that on the other hand it explains clearly all 
the salient mysteries and anomalies, has the potential to explain even much 
more yet unclear details in our auditory system and predicts other 
verifiable hearing phenomena.

The third chapter – Methods and experiments for verification – deals with 
perception experiments in which the ‘missing fundamental’ and the ‘strike 
note of bells’ are found to be normal hearing phenomena, so no illusions, 
while the ‘shift in pitch’, described in literature as result of a uniform 
frequency shift in higher ‘incomplete harmonic’ sound complexes, is found 
as an illusion, based on subjective perception of musically trained 
experimenters. 

The other four chapters describe details about the functioning of the 
cochlea.

If you combine this with the formulation of Richard Lyon in his comment to 
Ita Katz:

It would be much more robust to say that "The pitch is determined based on 
an approximately common periodicity of outputs of the cochlea," which I 
believe is consistent with your intent.

Why is this better?  

First, it doesn't say the periodicity is determined; what is determined is 
the pitch (even that is a bit of stretch, but let's go with it).  
Second, it doesn't depend on whether the signal is periodic, that is, 
whether harmonics exist. 
Third, it doesn't depend on being able to isolate and separately 
characterize components, harmonic or otherwise.  
Fourth, it doesn't need "multiples" (or divisors), but relies on the 
property of periodicity that a signal with a given period is also periodic 
at multiples of that period, so it only needs to look for "common" 
periodicities--which doesn't require any arithmetic, just simple neural 
circuits.  Fifth, it admits approximation, so that things like "the strike 
note of a chime" and noise-based pitch can be accommodated.  
Sixth, it recognizes that the cochlea has a role in pitch perception.  It's 
still not complete or perfect, but I think presents a better picture of how 
it actually works, in a form that can be realistically modeled.

You will observe that all these six aspects are forming parts of the 
concept we have named a new paradigm in hearing.

You can download the e-book version of our booklet from the website of the 
University of Utrecht:

http://igitur-archive.library.uu.nl/med/2011-0204-200555/UUindex.html

But for your convenience I have attached the PDF version of the booklet to 
this message



Regards

Pim Heerens


Attachment: Book Heerens de Ru EN.pdf
Description: Adobe PDF document