In a paper to be published April 29, 2011, in the journal Science, a team of Boston University researchers under the direction of Michael Hasselmo, professor of psychology and director of Boston University's Computational Neurophysiology Laboratory, and Mark Brandon, a recent graduate of the Graduate Program for Neuroscience at Boston University, present findings that support the hypothesis that spatial coding by grid cells requires theta rhythm oscillations, and dissociates the mechanisms underlying the generation of entorhinal grid cell periodicity and head-direction selectivity.

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