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The 'bookshelf illusion'--a real-world Zöllner-type illusion?
Otto H MacLin1, Dwight J Peterson
1University of Northern Iowa, Cedar Falls, IA 50614, USA.
Abstract:
We discovered an interesting perceptual distortion in our office where an upright lamp in front of a bookshelf was noticeably curved to form several subtle S-shaped bends. We realized that the books in the bookshelf fell in a particular manner, leaning in alternative directions, which caused the straight lamp to appear bent, creating what may be a real-world example of the Zöllner illusion. Evidence for the production of the illusion diagrammatically and an explanation for the effect are provided.
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