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bioRxiv · 10.1101/095935

The Constancy of Colored After-Images

Zeki, S.·Cheadle, S.·Pepper, J.·Mylonas, D.
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Abstract

We undertook psychophysical experiments to determine whether the color of the after-image produced by viewing a colored patch which is part of a complex multi-colored scene depends on the wavelength-energy composition of the light reflected from that patch. Our results show that, just as the color of a patch which is part of a complex scene is independent of the wavelength-energy composition of the light coming from it alone, but depends as well on the wavelength-energy composition of the light coming from its surrounds, so is the color of its after-image. Hence, traditional accounts of after-images as being the result of retinal adaptation or the perceptual result of physiological opponency, are inadequate. We propose instead that the color of after-images is generated after colors themselves are generated in the visual brain.

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Zeki, S., Cheadle, S., Pepper, J., Mylonas, D.. 2016-12-21. The Constancy of Colored After-Images. https://doi.org/10.1101/095935

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