carrell and opie research

[BOBC@xxxxxxxxxxxxxxxxxx]

I was interested to read al bregman's comments on the interesting research
carried out by carell and opie. This is a good example of what the list
should be about: informing researchers of interesting and relevant research
that they might otherwise overlook. In this spirit, and in relation to al's
suggestion about separating concurrent sounds via differences in AM rate,
I would like to mention an experiment by summerfield and culling. In a
double vowel paradigm, they measured the level of a target vowel
necessary for its identification in the presence of a masking vowel. they
found no effect of diferences in AM rate between masker and target.
My guess is that the PRESENCE of AM on the target will aid identification,
but, as Summerfield and Culling showed, there will be little or no effect of its
incoherence with that of a masker. This would tie in with McAdams' earlier
findings on FM incoherence.

The Summerfield and Culling article appeared in Phil Trans Roy. Soc. Lond. B,
vol 336, p 357-366 (june 1992), and also appears in a fascinating book,
"Processing of complex sounds by the auditory system" , edited by
R.P. Carlyon, C.J. Darwin, and I.J. Russell, to be published by Oxford Univ.
Press this month.

Bob Carlyon