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# [Neuroscience] Re: Wherefore art thou Neuron Code?

Glen M. Sizemore via neur-sci%40net.bio.net (by gmsizemore2 from yahoo.com)
Sat Apr 7 09:35:34 EST 2007

```Here's an experiment - you tell me what the outcome would be based on your
fanciful notions:

This experiment involves pigeons pecking illuminated Plexiglas "keys"
usually mounted behind a circular aperture in an aluminum wall of an operant
chamber.

Beginning of trial: Two keys are transilluminated, both with white lights,
and th pigeon can peck either key. Pecking the right hand key causes both
lights to be extinguished. After t s, both keys are illuminated, one with a
red light, the other with green (and the position is random), and the pigeon
can peck either key. If the pigeon pecks the red key, the lights go out and,
1.0 s later, a solenoid-operated feeder swings into position for 3.0 s. This
is followed by a 20.0 s inter-trial interval (ITI). If, on the other hand,
the pigeon pecks the green key, the lights go out, there is a 4.0 s delay,
and the pigeon gets 12.0 s access to the feeder at the end of the delay.
This is followed by an 8.0 s ITI. If, however, the pigeon had pecked the
left-hand key (when both lights are white - i.e., at the beginning of the
trial) there is a delay of t s, at the end of which only one key is lit, and
it is the green key. Pecking the green key has the same effect as it does on
the trials in which it is present with the red alternative.

What does the pigeon do under these circumstances when t=0.2 s? What is it
likely to do when t=20.0 s? Explain which white key is pecked. If the
red/green choice comes up, what does the pigeon do (if only the green
alternative is present the pigeon can only do one experimenter-defined
thing). If the red/green alternative is presented anyway as a probe (when
the procedure would otherwise dictate only the green key being illuminated)
what does the pigeon do?

Since all behavior is just a matter of "TD E/I-minimization," you should
have no trouble telling me, qualitatively, what happens to behavior as a
function of manipulating t. Right? No fair consulting any literature or
textbook - Jesus is watching.

<snip>

```