Motion-contrast computation without directionally selective motion sensors.

B K Dellen; J W Clark; R Wessel

doi:10.1103/physreve.70.031907

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Motion-contrast computation without directionally selective motion sensors.

B K Dellen·J W Clark·R Wessel

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Abstract

The detection of relative motion, i.e., motion contrast, has been reported for motion-sensitive neurons in several vertebrate systems, yet the mechanism underlying motion-contrast sensitivity remains unknown. An algorithm for computing motion contrast directly from the moving intensity distribution is proposed. In this algorithm, the time-dependent intensity distribution of the visual space is convolved with a periodic function. For coherent motion, the resulting convolution integral reduces to a traveling wave of fixed amplitude, while incoherent motion causes the amplitude to oscillate. The frequency of the amplitude oscillation provides a measure of motion contrast. The algorithm is successful in reproducing tuning curves derived from measurements of motion-contrast sensitivity in avian tectum and primate middle temporal area.

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Algorithms Animals Brain Computer Simulation Humans Models, Neurological Motion Perception Nerve Net Neurons Pattern Recognition, Automated Transducers Comparative Study Evaluation Study Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S.

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B K Dellen, J W Clark, R Wessel. 2004-09-21. Motion-contrast computation without directionally selective motion sensors.. https://doi.org/10.1103/physreve.70.031907

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