An Emergent Model of Visual Cortical Orientation Selectivity
نویسندگان
چکیده
We demonstrate a cortical circuit based on known anatomical details and cellular properties which achieves sharp orientation tuning despite poorly tuned thalamo-cortical input. Sharp tuning arises emergently from excitatory interactions between similarly tuned neurons, which also receive broadly tuned inhibition. This model accounts for data obtained from intracellular recording and pharmacological blockade studies, which had previously appeared to connict over the role of inhibition. We suggest that inhibition acts non-speciically and indirectly to maintain the selectivity of individual neurons by balancing strong intracortical excitation at the columnar level.
منابع مشابه
Journal of Neuroscience in press AN EMERGENT MODEL OF ORIENTATION SELECTIVITY IN CAT VISUAL CORTICAL SIMPLE CELLS
It is well known that visual cortical neurons respond vigorously to a limited range of stimulus orientations while their primary a erent inputs neurons in the lateral geniculate nucleus LGN respond well to all orientations Mechanisms based on intracortical inhibition and or converging thalamocortical a erents have previ ously been suggested to underlie the generation of cortical orientation sel...
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