Second, redeployment may offer a clearer way of organizing the search for the
neurological bases of cognitive function. In particular, it suggests that in order to
determine the functional role of a given brain region it is necessary to consider its
participation across multiple task categories, and not just focus on one, as has been the
typical practice. Making this claim a bit more specific, when modeling a given cognitive
function, and attempting to map that model onto brain areas, it will be necessary to
consider not just the model of the function under primary consideration, but also the
models of other functions recruiting the same brain areas, such that the sub-functional
elements of each model attribute the same role to the brain areas where they overlap.
Finding the functional role of a given brain area will be something like finding the right
letter to go into a box on a (multidimensional) crossword puzzle, determined not just by
the answer to a single clue, but by all the clues whose answers cross that box. This
makes the task both harder, because it is multiply constrained, but also easier, because it
offers the possibility of leveraging information from several sources to make the
attribution.
Third, and closely related to the last point above, as we come to recognize the diverse
cognitive functions supported by given brain regions, this should suggest more fine-
grained predictions about such matters as priming and cognitive interference, as well as
the likely effects (and the localization) of brain injuries. The knowledge that a given brain
area is used in multiple tasks and domains opens the possibility of designing experiments
leveraging these overlaps, e.g. in cross-domain priming or interference studies, or in the
development of cross-domain therapies for brain-injury patients.
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