Learned behavior consists of the operation of a sequence of tasks, with one leading
seamlessly into the other.  To perform these sequences, animals must "keep in mind" not
only where they are in the overall task, but also the plan for the upcoming movement.  The
prefrontal cortex has been shown to be critical in the performance of this "working
memory" and simple behavioral paradigms have been developed that test working memory in
its simplest, and therefore most approachable, form.  One of these simple behavioral
paradigms is the ODR (Oculomotor Delay Response) task, in which a monkey must remember,
over a period of seconds, a precise location to move his eyes when cued.  Prior evidence
from Pat Goldman-Rakic's lab has shown that during the "memory" period, cells in the
prefrontal cortex discharge in relation to the upcoming movement.  Two of her goals, which
are now also part of the goals of my own laboratory, were: 1) How does the network of
cells in the prefrontal cortex generate the persistent activity of the delay (memory)
period?  2) What is the functional architecture of working memory in the prefrontal
cortex?  Is there a spatial relation of delay period activity in the cortex that maps
easily onto the spatial relation of remembered locations?  Does this relation change with
different tasks?
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It is our goal to answer these questions.  In the first series of
experiments, we will address the mechanisms of generation of persistent activity through
intracellular recordings in awake, behaving monkeys.  Through these recordings, we will be
able to differentiate between network (and even excitatory and inhibitory) versus
intrinsic membrane contributions to the generation of the persistent activity associated
with working memory.
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In the second series of experiments (which may run concurrently
with the first) we will record from 64 multiple unit electrodes (two sets of 32 with one
of each placed in the prefrontal cortex of each hemisphere or two sets of 32 placed in the
prefrontal cortex of one hemisphere) during the performance of working memory tasks. 
These experiments will help illuminate whether or not there is a simple architecture to
working memory in the ODR task as well as the functional relationship between cortical
sites within and between hemispheres during the performance of working memory.