Subject: Re: comparison of vision and auditory system From: Harry Erwin <herwin(at)OSF1.GMU.EDU> Date: Mon, 2 Jun 1997 19:39:18 -0400On 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 herwin(at)gmu.edu Harry Erwin, Internet: herwin(at)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++).