Contrast is the relative difference in perception, intensity, or experience between two stimuli and their effect on each other.
Contrast, or contrast effect, is the difference in color, brightness, or tone that distinguishes one visual stimulus from another within the same visual field. Contrast may also refer to the differences in color and perceived brightness between different parts of the same image.
Psychologists study the contrast threshold, also called just noticeable difference, which is the point at which differences in two stimuli can just barely be detected. These concepts are used in the study of visual and spatial perception.
Understanding contrast effect has practical applications: for example, black and yellow have the lowest contrast effect, which means the largest percentage of the population can clearly detect the difference between these two colors. As a result, black and yellow are often used to mark school buses, traffic signs, and taxicabs.
See also Figure-ground perception ; Just noticeable difference ; Sensory modalities ; Vision .
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