Discrimination of compound gratings: Spatial-frequency channels or local features?
نویسندگان
چکیده
منابع مشابه
Discrimination of compound gratings: Spatial-frequency channels or local features?
Models based on spatial-frequency channels and local features provide alternative explanations for suprathreshold pattern discrimination. We compared psychophysical discrimination data with the predictions of the Wilson and Gelb channel model and three local-feature models. The features were peak-valley local contrast, peak-peak local contrast, and luminance gradients. We measured visual sensit...
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Previous studies have shown that adapting to a complex grating may produce little rise in the contrast threshold of a test grating whose spatial frequency matches one of the higher harmonics of the adapting pattern. The present study shows that adaptation may be strong if the adapting component of a complex grating appears visible as a separate grating. The adapting component could be made to a...
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ژورنال
عنوان ژورنال: Vision Research
سال: 1995
ISSN: 0042-6989
DOI: 10.1016/0042-6989(95)00030-4