Last but not least. Flashing lines.
In a periodic pattern of horizontally and vertically aligned quadrangles, two sets of illusory lines are seen to pulsate at orthogonal orientations, corresponding to the directions of knight's moves on a chessboard. The illusion seems to be governed by subtle rules of long-range interactions between parallel and non-parallel orientation filters.
Ninio
J
J
Laboratoire de Physique Statistique (associated to CNRS and to Paris 6 and Paris 7 Universities), France. jacques.ninio@lps.ens.fr
D006801:Humans; D009903:Optical Illusions / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology; D011601:Psychophysics