Splitting Colors Optical Illusion

Brain Decoder reports: [edited]

The Best Illusion of the Year Contest winner was "Splitting Colors,". We start off with two identical, flickering coloured stripes that remain unchanged throughout the demonstration.

Different surroundings make these stripes appear completely different. When the stripe is flanked by a yellow/blue pattern, drifting to the left, it changes appearance, and looks red and cyan, drifting to the right, while the same stripe, flanked by a red/cyan pattern drifting to the right, suddenly looks yellow and blue, drifting to the left.
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