Papathomas TV, Gorea A, Fehér A, Conway TE. "Attention-based texture segregation," Perception & Psychophysics, vol. 61(7), 1399-1410, 1999.



Do you see a vertical "edge" in this image, that separates the left and right parts?
See figures B and C below.
So, as you see form Figures B and C, there IS a vertical "edge" in Figure A. It is masked by the so-called "double conjunction" of the orientation and polarity (black/white).

What features are visible in Figures B and C?

Only the white bars of image A are shown   Only the -45 degree oriented bars of image A are shown