Stereokinesis with moving visual phantoms.

P Bressan; G Vallortigara

doi:10.1068/p160073

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Stereokinesis with moving visual phantoms.

P Bressan·G Vallortigara

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Abstract

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.

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P Bressan, G Vallortigara. 1987. Stereokinesis with moving visual phantoms.. https://doi.org/10.1068/p160073

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