Sinusoid = light bar + dark bar?

W McIlhagga; R Peterson

doi:10.1016/j.visres.2005.12.004

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Sinusoid = light bar + dark bar?

W McIlhagga·R Peterson

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Abstract

A sinusoidal grating can be viewed as a series of light and dark bars. Here we measure the contrast discrimination thresholds for light and dark bars individually, and find that the contrast discrimination thresholds for the whole sinusoid can be explained as ideal summation of the light and dark bar thresholds. We propose a model for light bar, dark bar, and sinusoidal contrast discrimination which involves local light adaptation and multiplicative noise. The model accounts for the data very well, and also accounts for contrast discrimination of light and dark edges.

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Adaptation, Ocular Contrast Sensitivity Discrimination, Psychological Humans Models, Neurological Models, Psychological Perceptual Masking Photic Stimulation Psychophysics Sensory Thresholds Journal Article

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W McIlhagga, R Peterson. 2006-02-15. Sinusoid = light bar + dark bar?. https://doi.org/10.1016/j.visres.2005.12.004

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