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PubMed · 11804633

Simultaneous S-cone contrast.

Claire S Barnes·Steven K Shevell
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Abstract

Chromatic induction is the change in appearance of one light caused by a second, nearby light. We measured chromatic induction in a central test viewed within an inducing field that was varied in only short-wavelength-sensitive (S) cone stimulation. The observer matched the appearance of the central test by adjusting the chromaticity of a haploscopically presented comparison field, seen by the other eye on a dark background. When the central test weakly stimulated S cones, the S-cone level in the surround caused little change in the color appearance of the test. When the central test substantially stimulated S cones, on the other hand, the appearance of the center showed S-cone contrast: raising the level of S in the surround reduced the level of S set to match the central test. Further, a surround that weakly stimulated S cones raised the matching S-cone level above that required without a surround (dark-adapted condition). These results cannot be explained by S-cone sensitivity loss or by a two-process model of adaptation. A cortical mechanism is proposed to mediate S-cone antagonism.

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Color PerceptionContrast SensitivityDark AdaptationFemaleHumansPsychophysicsRetinal Cone Photoreceptor CellsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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BibTeXRIS

Claire S Barnes, Steven K Shevell. 2002. Simultaneous S-cone contrast.. https://doi.org/10.1016/s0042-6989(01)00269-3

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