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PubMed · 3660643

Spatial influences on colour opponent contributions to pattern detection.

K T Mullen
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Abstract

The contribution of colour opponent mechanisms to detection thresholds is investigated at different spatial frequencies by presenting monochromatic, sinusoidal gratings on a uniform white background. Colour opponent mechanisms, characterised by a triple peaked spectral sensitivity function, determine threshold at low spatial frequencies (below 1 c/deg) and their contribution flattens the Weber function. They display low pass spatial frequency characteristics, becoming relatively more sensitive than non-opponent mechanisms as spatial frequency decreases. Colour opponent contributions are not revealed when the test grating and background are presented dichoptically.

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Color PerceptionForm PerceptionHumansLightMalePattern Recognition, VisualSensory ThresholdsSpectrophotometryJournal ArticleResearch Support, Non-U.S. Gov't

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K T Mullen. 1987. Spatial influences on colour opponent contributions to pattern detection.. https://doi.org/10.1016/0042-6989(87)90079-4

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