The file pavlov.g is a second demonstration of the hebbsynchan, written by
Srivatsun Sadagopan (with some additional modifications by Dave Beeman)
during the Computational Neuroscience course held December 6-18, 1999 at
the National Centre for Biological Sciences, Bangalore, India.

This greatly oversimplified model of Pavlovian conditioning is based on
Scripts/tutorials/tutorial5.g, which uses readcell to create a simple cell
with squid-like Na and K channels in the soma, and an excitatory synchan
(Ex_channel) in the single dendrite compartment.  It then adds an
excitatory hebbsynchan (hebb).  The hebbsynchan receives continous input
from the bell (the conditioned stimulus) in the form of a train of spikes.
Unlike tutorial5, there is no feedback connection from a spike generator in
the soma to either the synchan or hebbsynchan.

Initially food (the unconditioned stimulus) is present, represented by a
train of spikes to the non-Hebbian synchan.  Toggling the "Food!" button to
"No Food!" will remove this stimulus.  Clicking the Run button steps the
simulation for 0.1 seconds.  Reset clears the graphs and resets the
simulation to continue with the current weight.  The Unlearn button resets
the Hebbian weight to the original value.

Click on "Run" to run it for 0.1 seconds with the food stimulus present.
Repeat this a few times, toggle the food stimulus off, and then click on
"Run" again.  If the weight to the hebbian synapse has built up
sufficiently, the stimulus from the bell will be sufficient to cause the
cell to continue to fire in the absence of the food stimulus.  If not, give
it more food, or experiment with the Weight Change Rate dialog.
