Mechanisms of covert attention: External noise exclusion and stimulus enhancement in early visual areas
نویسندگان
چکیده
منابع مشابه
Blood oxygenation level-dependent contrast response functions identify mechanisms of covert attention in early visual areas.
Covert attention can lead to improved performance in perceptual tasks. The neural and functional mechanisms of covert attention are still under investigation. Using both rapid event-related and mixed designs, we measured the blood oxygenation level-dependent functional MRI contrast response functions over the full range of contrast (0-100%) in the retinotopically defined early visual areas (V1,...
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Keeping track of multiple moving objects is an essential ability of visual perception. However, the mechanisms underlying this ability are not well understood. We instructed human observers to track five or seven independent randomly moving target objects amid identical nontargets and recorded steady-state visual evoked potentials (SSVEPs) elicited by these stimuli. Visual processing of moving ...
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Shifts of covert attention differ depending on whether the shift is exogenously or endogenously motivated. The present study examined whether crossing imaginary meridia in the visual field influences shifts directed by central or peripheral cues. A two-alternative forced-choice discrimination task was employed under direction from 70 % valid central and peripheral cues. In comparison to central...
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ژورنال
عنوان ژورنال: Journal of Vision
سال: 2010
ISSN: 1534-7362
DOI: 10.1167/7.9.783