grouping and streaming

["W. M. Hartmann" <hartmann@xxxxxxxxxx>]

In connection with comments by Bruno Repp
and Chuck Watson on definitions for
"grouping" and "streaming"  ...

Auditory Grouping vs Stream Segregation
   - An Idiosyncratic Perspective

Auditory grouping is really important! It is
the wonderful process by which we sort out
sounds, making sense of our auditory world -
assigning perceived elements to different
sources or to backgrounds such as noise or
reverberation. Important though it is,
auditory grouping turns out to be hard to study.

Then there is stream segregation. It started
with the trill threshold by Miller and Heise,
Richard Warren and company, Leon van Noorden's
thesis, Al Bregman and innumerable coauthors,
Jay Dowling, and others. This is the sequential
pattern, the ya da ya da ya da, that we all know
and love. Stream segregation turns out to be easier
to study. Partly that's because it is almost
entirely attributable to peripheral channeling -
tonotopic and lateral.

Why should there be confusion about the difference
between auditory grouping and stream segregation?

(1) Stream segregation is a part of grouping. It
would be nice to think that by understanding
stream segregation we understand something
about grouping. There is a natural tendency to
want to think so. Maybe it's even partly true.

(2) About a decade ago - say 1988-1992 - a gang
of bright and enthusiastic computer guys from
Britain decided that grouping and streaming
were such similar concepts that both could be called
"streaming." This they proceeded to do. They did it
a lot and loudly. The honchos of stream segregation
knew better, of course, but they let it pass. For the
reason that they let it pass see (1).

Best,
Bill