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Measuring Visual Constancy for Stationary or Moving Objects

Naturevolume 191pages416417 (1961) | Download Citation



IF two objects of the same size are viewed so that one is twice as far from the eyes as the other, the retinal image of the farther object will be one-half the size of the image of the nearer object, but it does not appear half the size to the observer. They both appear almost the same size and the effect, which is due to perceptual interpretation of the retinal image, is known as size constancy1,2.

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  1. 1

    Thouless, R. H., Brit. J. Psychol., 21, 339 (1931) ; 22, 1 (1931) ; 22, 216 (1932).

  2. 2

    Vernon, M. D., A Further Study of Visual Perception (Cambridge Univ. Press, 1954).

  3. 3

    Wohlgemuth, A., “On the After-Effect of Seen Movement,” Brit. J. Psychol. Monograph Supplement (Cambridge Univ. Press, 1911).

  4. 4

    Duncker, K., “Induced Motion” in A Source Book of Gestalt Psychology, edit. by Ellis, W. (Routledge and Kegan Paul, London, 1938).

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  1. Psychological Laboratory, University of Cambridge

    • S. M. ANSTIS
    • , C. D. SHOPLAND
    •  & R. L. GREGORY


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