Stereokinesis with moving visual phantoms.
When a flat pattern composed of a solid ellipse with two symmetrical semirings (corresponding to the visible parts of a contour ellipse whose major axis is perpendicular to that of the solid ellipse) is slowly rotated in the frontoparallel plane, a compelling three-dimensional impression occurs. Subjects report seeing an egg-shaped object that is inserted into a circular ring: the two objects move solidly into three-dimensional space and a moving visual phantom is generated so that the ring appears completed by an illusory curved bar in the region closest to the observer during rotation. A number of variations of this illusion are presented. It is shown that stereokinetic phantoms (i) maintain the shape of the inducing elements; (ii) appear only after the stereokinetic transformation has taken place; and (iii) depend on the organization of the three-dimensional percept as a whole. Relations between stereokinetic phantoms and other completion phenomena are presented and discussed.
Bressan
P
P
Dipartimento di Psicologia Generale, Università di Padova, Italy.
Vallortigara
G
G
D003867:Depth Perception; D005133:Eye Movements; D005556:Form Perception; D006801:Humans; D007088:Illusions; D009039:Motion Perception; D009903:Optical Illusions; D010364:Pattern Recognition, Visual; D010466:Perceptual Closure