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PubMed · 8046537

Human luminance pattern-vision mechanisms: masking experiments require a new model.

J M Foley
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Abstract

A widely used model of simultaneous luminance pattern masking is based on mechanisms that sum inputs linearly and produce a response that is an S-shaped function of that sum. This model makes two predictions about masking: (1) Changing the masker spatial waveform will shift the threshold-versus-masker contrast function horizontally by a multiplicative constant. (2) Adding a second fixed-contrast masker will shift this function horizontally by an additive constant. Experimental tests do not support these predictions. The results can be explained by a new model that incorporates broadband divisive inhibition, consistent with physiology.

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Contrast SensitivityHumansLightMathematicsModels, BiologicalOrientationPattern Recognition, VisualVision, OcularJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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BibTeXRIS

J M Foley. 1994. Human luminance pattern-vision mechanisms: masking experiments require a new model.. https://doi.org/10.1364/josaa.11.001710

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