Model of visual contrast gain control and pattern masking

Watson, A. B.; Solomon, J. A.

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NASA NTRS · 20040172913

Model of visual contrast gain control and pattern masking

Watson, A. B.·Solomon, J. A.

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Abstract

We have implemented a model of contrast gain and control in human vision that incorporates a number of key features, including a contrast sensitivity function, multiple oriented bandpass channels, accelerating nonlinearities, and a devisive inhibitory gain control pool. The parameters of this model have been optimized through a fit to the recent data that describe masking of a Gabor function by cosine and Gabor masks [J. M. Foley, "Human luminance pattern mechanisms: masking experiments require a new model," J. Opt. Soc. Am. A 11, 1710 (1994)]. The model achieves a good fit to the data. We also demonstrate how the concept of recruitment may accommodate a variant of this model in which excitatory and inhibitory paths have a common accelerating nonlinearity, but which include multiple channels tuned to different levels of contrast.

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NASA Discipline Space Human Factors NASA Center ARC Contrast Sensitivity/physiology Perceptual Masking/physiology Pattern Recognition, Visual/physiology Models, Biological Visual Perception/physiology Photic Stimulation/methods Computer Simulation Human Support, Non-U.S. Gov't Support, U.S. Gov't, Non-P.H.S

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Watson, A. B., Solomon, J. A.. 1997-09-01. Model of visual contrast gain control and pattern masking. https://ntrs.nasa.gov/citations/20040172913

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