Opponent model for line interval discrimination: interval and vernier performance compared.

M J Morgan; D Regan

doi:10.1016/0042-6989(87)90147-7

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Opponent model for line interval discrimination: interval and vernier performance compared.

M J Morgan·D Regan

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Abstract

Vernier and spatial interval thresholds were determined as a function of contrast, using thin bars with a Gaussian luminance profile. The previously reported contrast dependence of vernier acuity was confirmed, but contrast had a much smaller effect upon interval acuity. A subsidiary experiment showed that the relative contrast of the two bars in an interval discrimination could be randomly perturbed over trials without substantially reducing acuity. A model of interval discrimination is developed, including an opponent stage between hypothetical spatial coincidence detectors.

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Discrimination, Psychological Form Perception Humans Models, Neurological Pattern Recognition, Visual Sensory Thresholds Visual Acuity Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S.

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M J Morgan, D Regan. 1987. Opponent model for line interval discrimination: interval and vernier performance compared.. https://doi.org/10.1016/0042-6989(87)90147-7

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