The split herringbone illusion. Alternating columns of tilting line segments move up and down. Under certain conditions one has the illusion that the herringbone pattern is moving continuously to the right. See text.

The split herringbone illusion. Alternating columns of tilting line segments move up and down. Under certain conditions one has the illusion that the herringbone pattern is moving continuously to the right. See text.

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Introduction When one looks at a two-dimensional scene of moving objects, one can usually assign a velocity to each point in that scene with little effort. This suggests that some early visual processes are able to generate a twodimensional velocity map using fast parallel computations. But it is not obvious how this should be done, and we are curr...

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... Direction selective cells were also found in the Complex layer; but unlike the Simple layer cells, these direction selective Complex layer cells showed evidence of additional invariances related to phase, multiple spatial frequencies and speed (not shown). This result suggests a potential for pattern-motion selectivity [Adelson et al. 1983]. We note that others have also demonstrated learning motion using sparse coding [Cadieu and Olshausen 2008]. ...
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