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Re: comparison of vision and auditory system

On Fri, 30 May 1997, Charles S. Watson wrote:

> Richard, right!
> And,
> as Lloyd Jeffress used to point out, if (1) it takes a millisecond or so
> to cross a synapse, (2) there is some reasonably proportional variance in
> that crossing time, and (3) there are several synapses between cochlea and
> cortex....then you'd darned well better extract any microsec-level
> temporal information early on in the system, because it won't be in very
> good shape further on...if it can be found at all.  (Lloyd probably said
> it more simply)  That was the point in putting his "coincidence detector"
> in the medial geniculate, and then later moving it down to the superior
> olive.
> Chuck

I'm currently working on a GENESIS model to investigate this specific
issue. The variation in trigger time of a cell that is the target of an
end bulb of Held is quite small. How small isn't certain, but I wouldn't
be surprised to be in the 10-100 microsecond range. That can then be
refined by convergence and averaging to produce the figures seen in
experiments. Answer due (for a course grade) by the end of the summer.
Ping me then.

Harry Erwin

Harry Erwin, Internet: herwin@gmu.edu, Web Page: http://osf1.gmu.edu/~herwin
Senior Software Analyst supporting the FAA, PhD student in computational
neuroscience--modeling how bats echolocate--and lecturer for CS 211 (data
structures and advanced C++).