Texture segmentation and pop-out from orientation contrast

In arrays of oriented lines, a target at a different orientation is effortlessly detected; it "pops out" from the pattern. Similarly, textures with line arrays at different orientations seem to dissect into separate areas with the spontaneous percept of distinct borders between them. In recent models, these perceptual phenomena were linked to the pre-attentive detection of certain features and of first-order differences in their spatial distribution. In contrast, however, psychophysical experiments show that texture segmentation and visual pop-out arise from orientation differences rather than from the orientation features themselves, a view which is supported by neurophysiological data from the monkey visual cortex.