Abstract
The inverted-T illusion was studied by the magnitude estimation method. The horizontal line in the inverted T is perceptually shorter than the same horizontal line presented singly, and the vertical line in the inverted T is perceptually longer than the same vertical line presented singly. Thus, the inverted-T illusion is due to both a perceptual lengthening of the vertical line and a shortening of the horizontal line. In the light of these findings, current theories of the illusion seem to give unsatisfactory explanations.
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The study on which this manuscript is based has been described in Report 34 of the Institute of Psychology, University of Padua, March 1981.
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Masin, S.C., Vidotto, G. A magnitude estimation study of the inverted-T illusion. Perception & Psychophysics 33, 582–584 (1983). https://doi.org/10.3758/BF03202941
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DOI: https://doi.org/10.3758/BF03202941