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Dr. Maida's research interests are in artificial intelligence and cognitive
science. His current and primary research effort develops multimedia tools to
interactively visualize neuronal simulations of small systems of neurons such as the rat hippocampus. The hippocampus
is an interesting part of the brain because, in humans, it is needed to add
new information to long-term memory. In rats, the hippocampus maintains
representations that allow the rat to remember how to return to previously
visited food locations. More details are known about neuronal structure and
function in the rat than in humans because neuroscientists can take more direct
measurements (e.g., inserting electrodes into the brain to measure neuronal
activity). Thus, more information is available to tell us how to "wire up"
virtual neurons to build a simulation. Neuroscientists have not yet produced a
complete wiring diagram of the hippocampus. Consequently, one must use many
forms of indirect evidence to first piece together a plausible model of
hippocampal function and then build a simulation to generate predictions.
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The predictions help one to judge whether the model is correct and may also
help neuroscientists design better experiments. Complications arise when
building such simulations. First, one does not have the luxury of using
existing mathematical models found in the artificial neural network literature.
Though such models are historically "brain inspired," they do not match the
structural details of the brain. Alternatively, if one builds a simulation
directly from the incomplete wiring diagram of the known nervous system, the
simulation's internal causal structure will remain a mystery. The simulation
will likely generate odd and counter-intuitive predictions that pose the
awkward problem of determining whether the implementation has a bug or whether
the implementation is correct but the model really does make the prediction.
These problems motivated his research to develop simulation tools to allow
cognitive and neuroscientists to study hippocampal models using exploratory
visualizations. The technology will allow a user to begin with an idealized
mathematical model
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and develop intuitions about causes underlying its function. The user may then
incrementally add biological realism to the model while comparing visualizations
over the series of refinements in order to judge effects of modifying the model.
His earlier research studies description-based communication protocols for
autonomous agents. The agents are assumed to cooperatively explore an unknown
environment such as the Martian surface. They independently discover or
rediscover new objects (such as geologically significant rocks) and must
exchange information about these discoveries. The description-based approach
derives from analogy to a similar communication problem in human language where
humans use descriptions to refer to objects that do not have names (such as
that plastic thing on the tip of your shoe lace).
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