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Updated: Mar 29, 2026

Creating Objects and Object Categories for Studying Perception and Perceptual Learning
Published on: November 2, 2012
Categorical perception of color: evidence from secondary category boundary
1Department of Psychology, King Saud University, Riyadh, Kingdom of Saudi Arabia.
Abstract:
Despite a plethora of behavioral research exploring the phenomenon of color categorical perception (CP) known as "better discrimination between pair of colors stimuli from different categories and pair of colors stimuli from the same category even when the stimulus differences between the pairs of stimuli are equal", most of the evidence for the CP of color was derived from Roman or top-to-down script readers and very rarely from right-to-left script readers in primary category. To date, no studies of color CP have been conducted on right-to-left script readers in secondary category boundary to support this theory. Three experiments have been conducted: Experiments 1 and 2 established the Arabic blue-purple secondary category boundary, and Experiment 3 tested the CP of color in the blue-purple category boundary. Sixty participants (30 men and 30 women) took part in this study. All spoke Arabic as their first language, and all were undergraduate or postgraduate students at King Saud University. Their ages ranged from 18-35 years with a mean age of 21.9 years (SD =5.2). The result indicated that for Experiments 1 and 2, it appeared that the Arabic blue-purple category boundary was approximately 10PB and it is in the same location as for English. For Experiment 3, reaction times in the between-categories condition were significantly faster than those in the within-category condition; this suggested that CP of color was shown in the Arabic's blue-purple secondary category boundary.
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