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Increment versus decrement detection
There are for me, at least two parts to this thread (see sig), Al
Bregman' comments, and Bruno Repp's question.
I agree with Al on this and see the time when what he would like to
see, becomes possible. My experience is that this is a continuation of
the decline of the present way of collecting and disseminating
information. There is much interesting work that has taken place
because the results have been locked into vaults, called publications,
whereas a new model of dissemination is found in the Wiki world, and
through sites such as MySpace (in the arts) and the kind of more rapid
communications found in FaceBook. In the professional world in which I
travel, these ideas are frowned upon, but in the educational world --
the world of the growing researcher, these are the models for
communication. More on the 'communications' thread later if anyone is
I find Bruno Repp's questions interesting, but am not able to provide
either a framework or a context in which to reply. If I read
correctly, the question is based around presenting 12 equally spaced
piano notes, all of the same dynamic level. I would like to be able to
hear what was presented in order to compare my perceptions with the
findings. Was the experiment worked in the middle register of the
piano where variations in decay times can be detected in the rate of
change of the harmonic partials? Was this done with a sampled piano
If it was done with an acoustic piano, then the spectral content of
each note changes at the microsecond level, and a well-formed ear
works on multiple levels of multiple parameters to detect changes.
More likely, this was done with a sampled instrument. Was this a
sampled instrument that each sample was transposed up and down one
semitone, or was it an 88 sample library?
Was the change of dynamic expressed simply by changing the amplitude
of the sound file, or was it a library that contained 88o piano
samples, that is, each note was recorded with 10 dynamic levels?
When the audio samples were being selected for the experiment, what
was the amount of variation? (.3 dB, 1 dB, 3 dB ...)
What was the period between the notes? What was the amount of change?
These, in my experience, are important factors. Were the note 3
seconds apart, or 350 ms apart? Was the amount of variance 10 ms, 50
ms or 150 ms?
Once the 'other' parameters are set, (and controled for), it might be
possible to start the examination of the role of memory in this study.
If all 12 notes were to be equally spaced and of equal amplitude, why
would the 'control' version need to be played?
If the control version were played with no variation in amplitude or
timing, did the participants report changes in amplitude or in timing?
I would see this as being a 'control' on the outcome of any subsequent
test. If in the 'control' (unvaried) version, all participants
reported that the notes were of equal amplitude and equal timing, then
I would consider their ability to detect differences as being
'significant'. But if there were errors in the 'control' version, how
would these be controled for in the test.
In response to why it is easier to detect increment than decrement,
the term hysteresis comes to mind immediately. http://en.wikipedia.org/wiki/File:B-H_loop.png
In the second part of the experiment I am most interested in the
'false alarms', as the subject has detected something changing when no
change has taken place.
In the second part, without knowing anything about the "so-called"
melodies, it is hard to comment. The word melody is both language-
constrained, and culturally constrained. Were these melodies based
upon a twelve-note equally tempered scale that showed 'tonal'
features? Was an underlying metric structure implied, or inherent? I
think of how the Viennese play waltzes. http://www.youtube.com/watch?v=KEdJ6pQXmoU
For a view of how Sachs and Nettl disagree on aspects of melody, start
Sometimes the conclusion drawn is the one which is predicted, but may
not be accurate. There was an article from March 2005, now lost, that
correlated physical violence in men as being inversely proportional to
the length of the first finger (Jupiter). The article went on to point
out that this correlation did not exist in women, for some reason.
Most palmists would explain this immediately -- a view that would be
rejected by scientists, in that in palmistry, Jupiter is reflective of
the individual's self-image regarding superiority / inferiority. Men
with feelings of inferiority may act this out in the form of
aggression, while in women this is reflected by submission. Violence
in women, as reported in the literature on chiromancy, is associated
with a long Jupiter, often supplemented by a short, bulbous nailed
thumb. But such nonsense is not the domain of serious scientific
consideration. Yet, a knowledge of this may strengthen your research.
Date: Fri, 2 Oct 2009 00:02:47 -0400
From: Al Bregman <al.bregman@xxxxxxxxx>
Subject: Re: Increment versus decrement detection
The query you sent about your new data was just the sort of thing
that the AUDITORY list should be used for -- the sharing of ideas
that can strengthen research and hasten development. Thanks from
all of us for sharing these findings. I hope that the responses will
beneficial effects for your research.
On Wed, Sep 30, 2009 at 10:37 AM, Bruno Repp <repp@xxxxxxxxxxxxxxxx>
I recently conducted some experiments in which participants had to
single changed tone in an isochronous melody consisting of 12
complex tones (piano tones) of different pitch but equal loudness.
change to be detected was either in intensity or in duration, and
either an increment or a decrement. These were four separate tasks,
intermixed. The melody containing the change was immediately
preceded by the
same melody not containing any change. I would be grateful for
references that would help me understand the following trends in my
(1) Decrements are harder to detect than increments. Is this well
previous psychoacoustic research? What is the reason?
(2) The pattern of variation in detection scores (hits and false
across the 12 tones in the melody, which reflects influences of pitch
contour and other factors, is uncorrelated between increment and
detection. It seems like these two tasks have little in common. Why?
(3) In increment detection, both hits and false alarms tend to
across the 12 tones in a melody, but decrement detection shows the
trend. It is as if tones were expected to become softer as the melody
Many thanks in advance for any helpful replies!
Bruno H. Repp
Haskins Laboratories 300 George Street
New Haven, CT 06511-6624
Tel. (203) 865-6163, ext. 236
Fax (203) 865-8963
Albert S. Bregman, Emeritus Professor
Psychology Department, McGill University
1205 Docteur Penfield Avenue
Montreal, QC, Canada H3A 1B1.
Office: Phone: (514) 398-6103, Fax: (514) 398-4896
Residence phone & fax: (514) 484-2592
Date: Sat, 3 Oct 2009 12:57:50 -0400
From: Fred Herzfeld <herzfeld@xxxxxxxxxxxx>
Subject: Jan Nordmark
Can anyone tell me the whereabouts of Dr. Nordmark. Up to the end of
1993 I was in touch with him
(in London and in Stockholm) regarding my new theories of the
hearing mechanisms in vertebrates.
This work is now "completed" and I cannot locate Jan to let him know
the final mathematical model.
Fred Herzfeld, MIT '54
78 Glynn Marsh Drive #59
End of AUDITORY Digest - 2 Oct 2009 to 3 Oct 2009 (#2009-226)