Color from invisible patterns.

Sherif Shady; Donald I A MacLeod

doi:10.1038/nn894

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Color from invisible patterns.

Sherif Shady·Donald I A MacLeod

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Abstract

Human pattern resolution is limited by optical blurring as well as neural filtering by a cascade of retinal and cortical sites with progressively lower resolution limits. Curiously, pattern structure can influence perceived color: a high-contrast, monochromatic (single wavelength) pattern appears desaturated (closer to white) relative to a uniform field of the same wavelength. Here we show that this desaturation is evident even when the pattern's frequency is too high for conscious perception, implicating a nonlinear process--namely light adaptation--at the level of single cone photoreceptors. We propose a neural mechanism in which fast, involuntary eye movements serve to shift control over perception between two competing cone populations, each operating at different levels of adaptation.

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Color Perception Contrast Sensitivity Eye Movements Humans Pattern Recognition, Visual Photic Stimulation Retinal Cone Photoreceptor Cells Time Factors Clinical Trial Journal Article Research Support, U.S. Gov't, P.H.S.

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Sherif Shady, Donald I A MacLeod. 2002. Color from invisible patterns.. https://doi.org/10.1038/nn894

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