Directional selectivity and its use in early visual processing.

D Marr; S Ullman

doi:10.1098/rspb.1981.0001

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Directional selectivity and its use in early visual processing.

D Marr·S Ullman

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Abstract

The construction of directionally selective units, and their use in the processing of visual motion, are considered. The zero crossings of delta 2G (x,y) * I(x,y) are located, as in Marr & Hildreth (1980). That is, the image is filtered through centre-surround receptive fields, and the zero values in the output are found. In addition, the time derivative delta[delta 2G(x,y) * I(x,y)]/delta t is measured at the zero crossings, and serves to constrain the local direction of motion to within 180 degrees. The direction of motion can be determined in a second stage, for example by combining the local constraints. The second part of the paper suggests a specific model of the information processing by the X and Y cells of the retina and lateral geniculate nucleus, and certain classes of cortical simple cells. A number of psychophysical and neurophysiological predictions are derived from the theory.

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Animals Geniculate Bodies Humans Mathematics Models, Biological Retina Space Perception Vision, Ocular Visual Cortex Visual Perception Journal Article Research Support, U.S. Gov't, Non-P.H.S.

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D Marr, S Ullman. 1981-03-06. Directional selectivity and its use in early visual processing.. https://doi.org/10.1098/rspb.1981.0001

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