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Updated: Jun 10, 2026
09:11
Controlled Rotation of Human Observers in a Virtual Reality Environment
Published on: April 21, 2022
The 'rotating snakes' in smooth motion do not appear to rotate
Erika Tomimatsu1, Hiroyuki Ito, Takeharu Seno
1Faculty of Design, Kyushu University, 4-9-1 Shiobaru, Minami-ku, Fukuoka 815-8540, Japan. tomimatsu@kyudai.jp
Perception
|August 4, 2010
Summary
The rotating snakes illusion requires a stationary image on the retina. Smoothly moving the image prevents the perception of rotation, even with continuous retinal image refreshment.
Area of Science:
- Visual perception
- Neuroscience
- Psychology
Background:
- The 'rotating snakes' is a visual illusion.
- This illusion involves the perception of rotating 'snakes' within a static image.
- The underlying mechanisms of this illusion are not fully understood.
Purpose of the Study:
- To investigate the conditions necessary for the 'rotating snakes' illusion.
- To determine the role of retinal image motion and refreshment in generating the illusion.
Main Methods:
- Presented the 'rotating snakes' visual stimulus.
- Manipulated image motion, including smooth movement and stationary presentation.
- Observed and recorded participant perception of snake rotation.
Main Results:
- Smoothly moving the image eliminated the perception of rotation.
- The illusion persisted when the image remained stationary on the same retinal position for a duration.
- Continuous retinal image refreshment during motion did not induce the illusion.
Conclusions:
- The 'rotating snakes' illusion is dependent on maintaining a static retinal image.
- Image stability, rather than continuous refreshment, is crucial for inducing the illusory rotation.
- This suggests a mechanism sensitive to prolonged, unchanging retinal stimulation.
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