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On the Mechanisms Underlying Directional Selectivity
1Department of Electrical Engineering, University of Houston, Houston, TX 77204-4793 USA.
Abstract:
Recent efforts in the understanding of motion detection and directional selectivity include electrophysiological studies using single photoreceptor stimulations and a combination of electrophysiology and neuropharmacology. Results of the former have been interpreted in favor of facilitator motion detection models while results of the latter have been interpreted in favor of inhibitory models. In this paper, this conflicting data interpretation problem is addressed by mathematically modeling some effects of neuropharmacological substances and by applying this formalism to a neural network model of directionally selective motion perception. The study offers a possible resolution to the paradox.
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