Illusions of perception of 3-D house models.
In five experiments some edgelines on different polyhedrons (house models in 3-D) were, from a certain vantage point, optically confluent, ie in optical prolongation of each other in 2-D on the retinal image and on photos. Other edgelines on the same polyhedrons were non-confluent, ie optically separate in 2-D. These conditions were found to lead to five different illusory shapes in 3-D. Five spatiofigural illusions were perceived. From these findings an edgeline principle is formulated that: "a straight edgeline in 2-D, whether confluent or separate, is perceived as a unitary and continuously straight edgeline in 3-D". To this is added a supplementary perceptual principle, an amodal completion principle. In the experiments reported here, the illusory perception of shapes in 3-D with confluent edgelines as well as the veridical perception of other shapes in 3-D with only separate or non-confluent edgelines could all be explained by the edgeline principle and the amodal completion principle. By applying the concepts of edgeline confluence and the edgeline principle, a new explanation of the Kopfermann (1930 Psychologische Forschung 13 293- 364) cube phenomena is proposed together with one example of how to test this explanation experimentally.
Nielsen
Torsten Ingemann
TI
Center for Visual Cognition, Department of Psychology, University of Copenhagen, Denmark. bekhoej@ruc.dk
D001108:Architecture; D003867:Depth Perception / Q000502:physiology*; D005556:Form Perception / Q000502:physiology*; D006801:Humans; D008960:Models, Psychological; D009903:Optical Illusions; D010364:Pattern Recognition, Visual / Q000502:physiology; D010469:Perceptual Distortion / Q000502:physiology; D011601:Psychophysics