Luminance thresholds for circular and bar-shape stimuli
نویسندگان
چکیده
منابع مشابه
Low number of luminance levels in the luminance noise increases color discrimination thresholds estimated with pseudoisochromatic stimuli
In pseudoisochromatic stimuli the presence of spatial and luminance noise forces the subject to discriminate the target from the background solely on the basis of chromaticity difference. Color-blind subjects may show difficulty to identify the target due to the elimination of borders and brightness clues caused by the luminance and spatial noise. Few studies have fully described the features o...
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We investigated the interactions between flicker thresholds and luminance pedestals using threshold versus contrast (TvC) and method of constant stimuli paradigms. High amplitude luminance pedestals were found to elevate flicker thresholds, but low amplitude luminance pedestals were unable to reduce flicker thresholds. Luminance pedestals elevated flicker thresholds more at low temporal frequen...
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The goal of this study was to compare luminance contrast discrimination and polarity identification in the inferred Parvocellular (PC-) and Magnocellular (MC-) pathways. The position identification task tested ability to locate a contrast change within a stimulus. The polarity identification task tested ability to classify the contrast change as either brighter or darker. Three paradigms were e...
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Errors in the perception of speed of moving visual stimuli can occur when presented stimuli are of unequal contrast and when they appear alongside additional modifier stimuli that move at different speeds. We have examined these misperceptions for chromatic and luminance grating stimuli in order to assess to what extent these different kinds of motion cue might be utilised in the analysis of sp...
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ژورنال
عنوان ژورنال: Bulletin of the Psychonomic Society
سال: 1975
ISSN: 0090-5054
DOI: 10.3758/bf03333183