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Updated: May 13, 2026

Creating Virtual-hand and Virtual-face Illusions to Investigate Self-representation
Published on: March 1, 2017
The Okuma illusion: a new illusion of leaning
Takashi Yasuda1, Takashi Ueda, Kenpei Shiina
1Faculty of Science and Engineering, Waseda University, 3-4-1, Okubo, Sinjuku-ku/Tokyo 169-8555, Japan. t-yasuda@asagi.waseda.jp
Abstract:
A new illusion demonstrating the perception of tilted objects is reported. Physically, all the objects in a rotated image should tilt at the same degree. We, however, found that the tilt of objects in a rotated frame is perceived differently. We tested several objects and found that this phenomenon is especially noticeable when an element in the image has a non-geometric shape. A possible mechanism for this illusion is proposed.
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