I need to follow up on the psychophysical info but the physiology
seems to make it unlikely that there is temporal (rather than a phase)
discrimination of such brevity, an aspect acknowledged in the review.

Kal


On Sun, 28 May 2006 10:46:03 -0400, "Robert Morein"
wrote:


"Kalman Rubinson" wrote in message
.. .
On Sat, 27 May 2006 09:44:11 -0400, "Robert Morein"
wrote:
How about this:
http://illumin.usc.edu/article.php?articleID=45&page=3

If the brain can localize based upon differential delays as small as 10
us,

This is highly unlikely and not supported by reference.

Kal

From http://www.physiol.ox.ac.uk/~raac/pd...aa_curBiol.pdf

"Humans can discriminate ITDs as small as 10-20 ?s [3] - an astonishing
achievement given that the duration of an
action potential is two orders of magnitude greater than this."

From http://www.pubmedcentral.gov/article...gi?artid=34336
" But even a sound coming directly from one side reaches the near ear only
600 ?s earlier than the far one, an interval comparable to the duration of a
single action potential. Our finest discrimination of a source's position
involves measurement of interaural time delay with a precision of less than
20 ?s-a seemingly impossible feat that we reflexively perform dozens of
times a day."

Interesting note on the speed of cilial response:
http://www.hhmi.org/news/coreydp.html

"Within 5 to 10 microseconds of this motion, channels in the hair cell open
and allow ions to enter - the first step in sending a sound signal to the
brain.

According to Corey, the rapidity of this response - which is as much as
1,000 times faster than the opening of similar channels in the eye in
response to light - indicated to scientists that the channel must respond
directly to the mechanical stimulus, rather than relying on a signal from
another molecule. The speed of the response was determined more than 20
years ago in the laboratory of HHMI investigator A. James Hudspeth - but
since that time, no one had been able to identify the channel protein."