There are 10 messages totalling 716 lines in this issue.
Topics of the day:
1. Is there considerable phase locking up to 6 kHz? (4)
2. 2 post-doctoral positions in music structure research (London, UK)
3. Critical bands - fixed or "floating"?
4. Discussion about "place pitch" concept (3)
5. seeking an image of the auditory system
----------------------------------------------------------------------
Date: Thu, 18 Mar 2004 09:53:10 +0100
From: Eckard Blumschein <Eckard.Blumschein@E-TECHNIK.UNI-MAGDEBURG.DE>
Subject: Re: Is there considerable phase locking up to 6 kHz?
Dear all,
I appreciate clear objections against the idea of periodicity detection
from temporal envelope by Roy Patterson: "The work on IRN stimuli suggests
that periodicities are not a necessary and sufficient condition for
processing complex pitch, since there are no periodicities in the IRN
waveform (see Yost et al, 1996), yet they have a clear pitch (see Yost,
1996a). Our current work suggests that the information for processing the
pitch of IRN stimuli is not in the envelope."
However, we all should be wary of thoughtlessly using notions like
spectrum and temporal fine structure.
Already the fundamentally inappropriate traditional spectrogram
illustrates that the iteration of a segment of noise without any spectral
profile introduces an audible spectral signature. Of course, the
FCT-based natural spectrogram shows a more realistic picture of firing
pattern in the auditory nerve. I remind those who do not trust in FCT,
because they wrongly put it in the drawer of an exotic mathematical idea
while it actually replaces FT, of the need to define what we are talking
about if we are using terms like spectral component.
Martin Braun is certainly correct in that, there are at least two main
streams of auditory information within each CN. However, he apparently
ignores tonotopy as long as he doesn't follow my suggestion that place
code is the best base for subsequent temporal processing. For more than a
century, Fourier analysis and place code were considered the basis of
hearing and of related audio technology because alternative temporal
models failed.
Why not seriously dealing with an unseen mathematically correct and
physiologically plausible model that unites function of cochlea and brain
in a somewhat strange hidden manner which is already known as cepstral
analysis? It also may elucidate why different codes contribute to a
unitary pitch.
I do not appreciate glossing over FCT as a red herring since such
emotional arguments are difficult to falsify. Nonetheless, I would hope
that expert listeners confirm or deny the putative 400/800 Hz confusion.
So far, I am only aware of a plausible 50/100 Hz confusion in case of
iterated noise segments with alternating polarity inversion (Warren &
Wrightson 1981).
Eckard Blumschein
------------------------------
Date: Thu, 18 Mar 2004 09:46:52 +0000
From: Michael Casey <casey@SOI.CITY.AC.UK>
Subject: 2 post-doctoral positions in music structure research (London,
UK)
Dear Auditory list members,
the following post-doctoral positions may be suitable for recent PhD's
with a background in auditory research. (Closing March 22nd).
Best regards,
Dr. Michael Casey, Lecturer
Centre for Computational Creativity
City University, London
http://ccc.soi.city.ac.uk
+44 (0)20 7040 8380
Job Title: Post-Doctoral Research Assistant for SeMMA project
Tenure: Fixed term for three years
Responsible to: Prof. Mark Sandler (Queen Mary College University of
London) and Dr Michael Casey (City University London)
Project Overview:
The 3 year Engineering and Physical Sciences Research Council (EPSRC)
project Hierarchical Segmentation and Semantic Markup of Musical Signals
is a collaboration between the Centre for Digital Music at Queen Mary
University of London and the Centre for Computational Creativity at City
University. It is concerned with the extraction and exploitation of
musically relevant semantic features direct from musical content. Each
partner will employ one post-doctoral researcher. It is expected that both
researchers will spend some time in each other's laboratory, which are
only about 2 miles apart in Central London.
Main Duties:
The aim of this research programme is to develop new signal processing
algorithms that perform meaningful segmentations of musical signals. The
specific objectives are to:
develop new machine learning techniques to automatically produce a
hierarchical segmentation directly from an audio recording
evaluate the methods and algorithms using a test corpus consisting of a
range of different musical styles and recording qualities
develop a framework to construct two applications (information retrieval
& intelligent editing) and evaluate the performance and opportunities
The post-docs will engage in research to fulfil the requirements of the
grant. They must have expertise in some of the following research areas:
DSP for Music and Audio.
Statistical (Bayesian) Modelling and Statistical Mechanics
Low level audio feature extraction (e.g. MFCC)
Databases and Music Information Retreival
MPEG7, XML, C++, Java, Matlab
They will be required to co-operate with and to communicate with members
of the research team at the other partner, and be required to attend
regular project meetings.
The post-docs will be required to write and to edit contributions to
project documents, including learned papers for journals and conferences.
Additionally the post-doc will be offered the opportunity to lecture on
Masters level courses as part of career development.
Deadline for applicatoin: 5PM GMT 22nd March '04
For details of how to apply see
http://www.city.ac.uk/hr/jobs/04046/dp.htm
------------------------------
Date: Thu, 18 Mar 2004 14:26:27 +0100
From: Martin Braun <nombraun@TELIA.COM>
Subject: Re: Is there considerable phase locking up to 6 kHz?
On Thursday, March 18, 2004 3:40 AM, Richard F. Lyon wrote:
> Martin, thanks for your comments. I will be more than happy to adopt
> your suggestion and give up the old idea of "place pitch" as
> unsupportable by any evidence.
>
> However, I'm not sure I like your division of timing pathways.
>
> The first one (a), with "phase locking of resolved harmonics" seems
> to be rather narrowly construed. Sound does not in general
> consistent of discrete sinusoids, since it is not in general
> periodic, so the mechanisms must be much more general. Even for
> periodic sounds, partials are in general only partly "resolved". The
> phase locking in the auditory nerve will follow the time structure of
> arbitrary waveforms at the different points along the cochlea.
> Conceptualizing in terms of sinusoids does more harm then good, in my
> opinion.
Yes, Dick, what the cochlea and then various nuclei in the auditory
pathways do is much more than delivering clean phase coupling to clean
sinusoid components. We see various techniques of band filtering and the
final results are probabilistic. But, as FFR studies showed (frequency
following responses recorded on the human scalp originating in the upper
brain stem), the neural population responses reflect a remarkably clean
periodicity coding upon complex periodic stimuli.
> The second pathway (b) seems funny, too. Why would information be
> encoded "for the purpose of sound localization" and then used for a
> different purpose?
Because many, if not most, neurons in the cochlear nuclei and in the
nuclei of inferior colliculus are multiplexing units. Monaural delay
coding in the cochlear nuclei and binaural delay coding in nuclei of the
superior olivary complex does not occur in units that are exclusively
engaged in sound localization. Therefore, not only the results of delay
analysis are delivered upstream, but also the raw delay periods. The
period detectors in the midbrain then (periodicity tuned neurons) respond
to these delays, simply because they present period information.
The environments that our hearing has adapted to did not present stimuli
where proper and secondary pitch pathways can come up with conflicting
results. So there was no evolutionary advantage of fully separating the
mechanisms for sound localization and pitch extraction.
Martin
--------------------------------
Martin Braun
Neuroscience of Music
S-671 95 Klässbol
Sweden
web site: http://w1.570.telia.com/~u57011259/index.htm
------------------------------
Date: Thu, 18 Mar 2004 13:52:55 -0000
From: "Richard H." <auditory@AUGMENTICS.COM>
Subject: Critical bands - fixed or "floating"?
Hi,
Newbie question: are the critical bands physically real measurable bands -
or are they simply a "ratiometric artefact"?
regards,
Richard
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------------------------------
Date: Thu, 18 Mar 2004 17:24:55 +0100
From: Eckard Blumschein <Eckard.Blumschein@E-TECHNIK.UNI-MAGDEBURG.DE>
Subject: Re: Is there considerable phase locking up to 6 kHz?
Dear Martin,
At 14:26 18.03.2004 +0100, you wrote:
... many, if not most, neurons in the cochlear nuclei and in the nuclei
> of inferior colliculus are multiplexing units.
Do you know how a multiplexer works, and can you specify the pertaining
role you are ascribing to spherical bushy cells and T-multipolars of CN,
at least?
Regards,
Eckard
------------------------------
Date: Thu, 18 Mar 2004 08:33:15 -0800
From: "Richard F. Lyon" <DickLyon@ACM.ORG>
Subject: Re: Is there considerable phase locking up to 6 kHz?
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Content-Transfer-Encoding: quoted-printable
At 9:53 AM +0100 03/18/2004, Eckard Blumschein wrote:
> However, we all should be wary of thoughtlessly using notions like
> spectrum and temporal fine structure.
I'm glad that we have that point of agreement.
> Already the fundamentally inappropriate traditional spectrogram
> illustrates that the iteration of a segment of noise without any
> spectral profile introduces an audible spectral signature. Of course,
> the FCT-based natural spectrogram shows a more realistic picture of
> firing pattern in the auditory nerve. I remind those who do not trust
> in FCT, because they wrongly put it in the drawer of an exotic
> mathematical idea while it actually replaces FT, of the need to define
> what we are talking about if we are using terms like spectral component.
I'm trying to decide whether that comment is=20
directed at me. Certainly I've always been very=20
careful about concepts such as spectral=20
components, as I believe the such=20
frequency-domain concepts often force thinking=20
into wrong directions. I also don't regard=20
=46ourier Cosine Transforms as any more exotic than=20
other mathematical transforms. But I do mistrust=20
them as auditory models.
> Martin Braun is certainly correct in that, there are at least two main
> streams of auditory information within each CN. However, he apparently
> ignores tonotopy as long as he doesn't follow my suggestion that place
> code is the best base for subsequent temporal processing. For more than
> a century, Fourier analysis and place code were considered the basis of
> hearing and of related audio technology because alternative temporal
> models failed.
Here we have a different view of the impact of=20
the Fourier analysis approach and place code on=20
the historical development of auditory theory.=20
I'm more aligned with a quote that I heard=20
attributed to Georg von B=E9k=E9sy: "Dehydrated cats=20
and the application of Fourier analysis to=20
problems in hearing become more and more a=20
handicap for progress in hearing research."
As far as I know, temporal models have succeeded=20
more than failed (that is, temporal models of=20
processing in and beyond the cochlea, not to be=20
confused with temporal processing of raw sound=20
waveforms). Spectral models, while widely used,=20
often run into limitations that make them "fail".
> Why not seriously dealing with an unseen mathematically correct and
> physiologically plausible model that unites function of cochlea and
> brain in a somewhat strange hidden manner which is already known as
> cepstral analysis? It also may elucidate why different codes contribute
> to a unitary pitch.
Cepstral analysis is fine as far as it goes. But=20
it is rather limiting, as a mathematical=20
framework that stops short of describing what's=20
going on in detail, essentially ignoring temporal=20
fine structure on the auditory nerve.
> I do not appreciate glossing over FCT as a red herring since such
> emotional arguments are difficult to falsify. Nonetheless, I would hope
> that expert listeners confirm or deny the putative 400/800 Hz
> confusion. So far, I am only aware of a plausible 50/100 Hz confusion
> in case of iterated noise segments with alternating polarity inversion
> (Warren & Wrightson 1981).
OK, this part I'm certain is directed at me,=20
since I mentioned red herrings. My comment was=20
not directed at the FCT itself, which is a=20
perfectly fine transform, but rather to the idea=20
that if you use it then you can ignore questions=20
of temporal fine structure. Specifically, what I=20
said quoted your assertion, this way ...the idea=20
that "FCT is the only realistic cochlear=20
transform" is just a mathematician trying to=20
force a biological system to be something he can=20
analyze.' I apologize for putting it in such=20
personal terms.
Dick
> Eckard Blumschein
--============_-1132494356==_ma============
Content-Type: text/html; charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
<!doctype html public "-//W3C//DTD W3 HTML//EN">
<html><head><style type=3D"text/css"><!--
blockquote, dl, ul, ol, li { padding-top: 0 ; padding-bottom: 0 }
--></style><title>Re: Is there considerable phase locking up to 6
kHz?</title></head><body>
<div>At 9:53 AM +0100 03/18/2004, Eckard Blumschein wrote:</div>
<blockquote type=3D"cite" cite>However, we all should be wary of
thoughtlessly using notions like spectrum</blockquote>
<blockquote type=3D"cite" cite>and temporal fine structure.</blockquote>
<div><br></div>
<div><br></div>
<div>I'm glad that we have that point of agreement.</div>
<div><br>
<br>
</div>
<blockquote type=3D"cite" cite>Already the fundamentally inappropriate
traditional spectrogram illustrates<br>
that the iteration of a segment of noise without any spectral
profile<br>
introduces an audible spectral signature. Of course, the FCT-based
natural<br>
spectrogram shows a more realistic picture of firing pattern in
the<br>
auditory nerve. I remind those who do not trust in FCT, because
they<br>
wrongly put it in the drawer of an exotic mathematical idea while
it<br>
actually replaces FT, of the need to define what we are talking about
if we</blockquote>
<blockquote type=3D"cite" cite>are using terms like spectral
component.</blockquote>
<div><br>
<br>
</div>
<div>I'm trying to decide whether that comment is directed at me.
Certainly I've always been very careful about concepts such as
spectral components, as I believe the such frequency-domain concepts
often force thinking into wrong directions. I also don't regard
=46ourier Cosine Transforms as any more exotic than other mathematical
transforms. But I do mistrust them as auditory models.</div>
<div><br></div>
<div><br></div>
<blockquote type=3D"cite" cite>Martin Braun is certainly correct in
that, there are at least two main<br>
streams of auditory information within each CN. However, he
apparently<br>
ignores tonotopy as long as he doesn't follow my suggestion that place
code<br>
is the best base for subsequent temporal processing. For more than
a<br>
century, Fourier analysis and place code were considered the basis
of<br>
hearing and of related audio technology because alternative temporal
models<br>
failed.</blockquote>
<div><br>
<br>
</div>
<div>Here we have a different view of the impact of the Fourier
analysis approach and place code on the historical development of
auditory theory. I'm more aligned with a quote that I heard
attributed to<font face=3D"Arial" size=3D"-3" color=3D"#000000"> Georg von
B=E9k=E9sy</font>: "Dehydrated cats and the application of
=46ourier analysis to problems in hearing become more and more a
handicap for progress in hearing research."</div>
<div><br></div>
<div>As far as I know, temporal models have succeeded more than failed
(that is, temporal models of processing in and beyond the cochlea, not
to be confused with temporal processing of raw sound waveforms).
Spectral models, while widely used, often run into limitations that
make them "fail".</div>
<div><br></div>
<div><br></div>
<blockquote type=3D"cite" cite>Why not seriously dealing with an unseen
mathematically correct and<br>
physiologically plausible model that unites function of cochlea and
brain<br>
in a somewhat strange hidden manner which is already known as
cepstral<br>
analysis? It also may elucidate why different codes contribute to a
unitary</blockquote>
<blockquote type=3D"cite" cite>pitch.</blockquote>
<div><br></div>
<div><br></div>
<div>Cepstral analysis is fine as far as it goes. But it is
rather limiting, as a mathematical framework that stops short of
describing what's going on in detail, essentially ignoring temporal
fine structure on the auditory nerve.</div>
<div><br>
<br>
</div>
<blockquote type=3D"cite" cite>I do not appreciate glossing over FCT as
a red herring since such emotional<br>
arguments are difficult to falsify. Nonetheless, I would hope that
expert<br>
listeners confirm or deny the putative 400/800 Hz confusion. So far, I
am<br>
only aware of a plausible 50/100 Hz confusion in case of iterated
noise</blockquote>
<blockquote type=3D"cite" cite>segments with alternating polarity
inversion (Warren & Wrightson 1981).</blockquote>
<div><br></div>
<div><br></div>
<div>OK, this part I'm certain is directed at me, since I mentioned
red herrings. My comment was not directed at the FCT itself,
which is a perfectly fine transform, but rather to the idea that if
you use it then you can ignore questions of temporal fine structure.
Specifically, what I said quoted your assertion, this way ...the idea
that "FCT is the only realistic cochlear transform" is just
a mathematician trying to force a biological system to be something he
can analyze.' I apologize for putting it in such personal
terms.</div>
<div><br></div>
<div>Dick</div>
<div><br>
<br>
</div>
<blockquote type=3D"cite" cite>Eckard Blumschein</blockquote>
<div><br></div>
</body>
</html>
--============_-1132494356==_ma============--
------------------------------
Date: Thu, 18 Mar 2004 18:49:39 +0100
From: "Dr. Uwe Baumann" <uwe.baumann@HNO.MED.UNI-MUENCHEN.DE>
Subject: Discussion about "place pitch" concept
Dear Martin, Christian, Dick, Roy, and others -
The ongoing discussion about temporal pitch emerged the statement=20
"There is no physiology of a "place pitch", and this concept should be =
given up." by Martin Braun, which was supported by several others.
I would like to point the discussion to electrical excitation of the =
spiral ganglion cells by means of a cochlear implant electrode array.
With direkt pulsatile stimulation of the auditory nerve, Zengs' (2002) =
as well as our own results (Baumann & Nobbe, submitted) do clearly show, =
that:
a) the upper limit for temporal pitch with pulsatile stimulation is 300 =
pulses per second
b) pure temporal pitch discrimination (without place cues) is =
astonishingly worse: depending on base rate an average rate change of =
23% to 33% pulse rate is required to elicit a just noticeable difference =
in terms of pitch perception.
c) The absence of a difference in terms of repetition rate =
discrimination between apical and basal electrode locations indicates =
that a reduction of the base rate/place mismatch does not improve =
discrimination performance.
d) Concerning autocorelation based models of pitch perception:
"With electrical stimulation, identical temporal information can be =
provided to different channels by independently stimulating basal and =
apical electrodes. The summed autocorrelation function should be =
identical between basal and apical stimulation, predicting an =
independence of rate pitch on the place of stimulation. This prediction =
is clearly inconsistent with the observed joint dependence
of pitch perception on rate and place [by pulsatile electrical =
stimulation]." (Zeng, 2002)
There have been discussions about the reasons of the poor contribution =
of temporal information to pitch perception in electrical hearing. Poor =
neural survival is one major argument. But even in case of a reduced =
number of fibers, the rate code will be transmitted more accurately in =
electrical hearing than by normal acoustical stimulation (Hartmann, =
1984).
These and several other arguments will be discused in our alredy =
mentioned (presumably upcoming) paper.
The outlined observations are not able to counter the notion "There is =
no physiology of place pitch", but they clearly indicate that there is a =
place pitch in psychophysical electrical stimulation of the cochlea by =
means of intracochlear electrode arrays.
Uwe
Dr.-Ing. Uwe Baumann
Electrical Engineer/Medical Physicist/Audiologist
University of Munich
Dept. Otolaryngology/Audiology
Marchioninistr. 15
D-81377 M=FCnchen
Tel: ++49-89-7095-3878
Fax: ++49-89-7095-6869
email: uwe.baumann@med.uni-muenchen.de
www: http://ghn86x.hno.med.uni-muenchen.de/bau
References:
Baumann U, Nobbe A (2004) Pulse rate discrimination with deeply inserted =
electrodes. Hearing Research submitted
Hartmann R, Topp G, Klinke R (1984) Discharge patterns of cat primary =
auditory fibers with electrical stimulation of the cochlea. Hear. =
Res.13:47-62
Zeng, F.-G. (2002) Temporal pitch in electric hearing. Hear.Res. 174, =
101-106.
------------------------------
Date: Thu, 18 Mar 2004 23:07:23 +0100
From: Martin Braun <nombraun@TELIA.COM>
Subject: Re: Discussion about "place pitch" concept
On Thursday, March 18, 2004 6:49 PM, Uwe Baumann wrote:
> There have been discussions about the reasons of the poor contribution
> of temporal information to pitch perception in electrical hearing. Poor
neural
> survival is one major argument. But even in case of a reduced number of
> fibers, the rate code will be transmitted more accurately in electrical
> hearing than by normal acoustical stimulation (Hartmann, 1984).
Because this is an accuracy that is enforced rather "brutally". The price
of the "brutality" is the low limit of neural phase coupling. More
important than reduced numbers of afferent fibers in the cochlea probably
is the absence of inner hair cells and their afferent synapses. Both are
extremely sophisticated machines, which we only have started to explore.
The secrets of HF period coding are hidden here.
> The outlined observations are not able to counter the notion "There is
> no physiology of place pitch", but they clearly indicate that there is a
place
> pitch in psychophysical electrical stimulation of the cochlea by means
> of intracochlear electrode arrays.
Thanks, Uwe. This is an important point. For peripheral encoding of period
information the place of encoding is important, also in normal hearing.
But this is not what theories of "place pitch" were dealing with. Rather,
they suggested a coding of pitch by central cochleotopic patterns of
harmonics, for which physiological evidence could never be found.
By the way, there is a very recent and highly interesting paper which
demonstrates the importance of peripheral encoding place: Oxenham et al.
"Correct tonotopic representation is necessary for complex pitch
perception", which appeared in Proc. Natl. Acad. Sci. USA, published
online before print January 12, 2004 (10.1073/pnas.0306958101).
This paper should be recommended to all who have to do with cochlear
implants. It is also of importance for physiological concepts of pitch.
For this reason I published a short comment on it:
http://w1.570.telia.com/~u57011259/Oxenham.htm
Martin
--------------------------------
Martin Braun
Neuroscience of Music
S-671 95 Klässbol
Sweden
web site: http://w1.570.telia.com/~u57011259/index.htm
------------------------------
Date: Thu, 18 Mar 2004 17:47:40 -0500
From: Mark Ballora <ballora@PSU.EDU>
Subject: seeking an image of the auditory system
Hello --
I am looking for an image of the human auditory system for use in a
brief article that I am writing on psychoacoustics.
Can anyone on the list point me towards images that might be
available for licensing for use in a commercial publication
(Electronic Musician magazine).
Thank you --
Mark Ballora
--
=========================================================================
====== Mark Ballora
http://www.music.psu.edu/Faculty%20Pages/Ballora/index.html
Assistant Professor - Music Technology
School of Music/Dept. of Integrative Arts
The Pennsylvania State University tel. (814) 863-3386
14 Music Building II fax (814) 865-6785
University Park, PA 16802-1901 USA
The mysterious is the source of all true art and science.
He to whom this emotion is a stranger,
who can no longer pause to wonder and stand rapt in awe,
is as good as dead: his eyes are closed.
Albert Einstein
=========================================================================
======
------------------------------
Date: Fri, 19 Mar 2004 10:51:30 +1100
From: Colette McKAY <colette@UNIMELB.EDU.AU>
Subject: Re: Discussion about "place pitch" concept
Uwe Baumann wrote:
* d) Concerning autocorelation based models of pitch perception:
* "With electrical stimulation, identical temporal information can
be = provided to different channels by independently stimulating basal
and = apical electrodes. The summed autocorrelation function should be =
identical between basal and apical stimulation, predicting an =
independence of rate pitch on the place of stimulation. This prediction =
is clearly inconsistent with the observed joint dependence
* of pitch perception on rate and place [by pulsatile electrical =
stimulation]." (Zeng, 2002)
*=09
However, there are many studies which have consistently demonstrated the =
independence of percepts related to rate of stimulation and place of =
stimulation. The earliest of these was Tong et al. (Tong, Y. C., P. J. =
Blamey, et al. (1983). "Psychophysical studies evaluating the =
feasibility of a speech processing strategy for a multiple-channel =
cochlear implant." Journal of the Acoustical Society of America 74(1): =
73-80.) who used a multidimensional scaling task and showed a =
2-dimensional stimulus space relating to rate and electrode position.
A more recent study was by McKay, C., H. McDermott, & Carlyon. (2000). =
"Place and temporal cues in pitch perception: are they truly =
independent?" Acoustic Research Letters Online 1(1): 25-30. We showed =
that subjects could use independent information about rate and place =
changes in a difference-limen task. Combined changes which were =
inconsistent (e.g. increasing rate and apicalward place shift) were =
equally discriminable to changes which were consistent and this was =
inconsistent with the idea that such information is combined into a =
single 'pitch' percept or.=20
The latter study is inconsistent with studies such as Zeng (2002) in =
which the both place and rate seem to influence the 'pitch' estimate of =
the subject. My personal view on the reason for this inconsistency is =
that, when subjects are asked to rate the 'pitch' of sounds which differ =
both in pitch and timbre (as in the Zeng experiment) they are forced to =
make decisions based on two different percepts at once, and thus are =
forced to respond based on some weighted average of the two percepts. =
Also, an implantee (or even a normal hearing person) is likely to rank =
timbre as a pitch difference if played two sounds differing only in =
timbre. Experiments like this one tend to suggest that you can adjust =
the rate on one electrode to make an equal pitch to stimulation on =
another electrode at a different rate. However, if these two stimuli =
were directly compared by a subject they would immediately tell you they =
are very different sounds, with different pitches, and they would choose =
one of the place or rate percepts to tell you which one had the higher =
pitch.
Colette McKay
***********************************************************************
A/Prof Colette McKay
NHMRC Principal Research Fellow
Department of Otolaryngology, The University of Melbourne
384-388 Albert St. East Melbourne, Australia
Phone +613 9667 7506 Fax +613 9667 7518
email: colette@unimelb.edu.au
**********************************************************************
------------------------------
End of AUDITORY Digest - 17 Mar 2004 to 18 Mar 2004 (#2004-54)
**************************************************************