Illusion news 10

since May 1, 2008

A workwhop on the optimized Fraser-Wilcox illusions, which "Rotating snakes" depends on, was held in the 72nd annual convention of the Japanese Psychological Association. <August 8, 2008>

WS005 Experimental studies of anomalous motion illusions September 19, 2008
10:00-12:00 E207

  Organizer   Kyoto University   Hiroshi ASHIDA  

  Organizer   Ritsumeikan University   Akiyoshi KITAOKA  

  Moderator   Kyoto University   Hiroshi ASHIDA  

  Speaker   Optimized Fraser-Wilcox illusions: A pictorial classification by Akiyoshi Kitaoka Ritsumeikan University   Akiyoshi KITAOKA  

  Speaker   The effects of eccentricity and retinal illuminance on the illusory motion seen in a stationary luminance gradient University of Tokyo    Rumi HISAKATA  

  Speaker   Infants see the illusory motion in the static figure Japan Women's University   So KANAZAWA  

  Speaker   Functional brain imaging of the Rotating Snakes illusion by fMRI Tohoku University   Ichiro KURIKI

  Commentator   Some comments NTT Communication Science Laboratories   Tatsuto TAKEUCHI

The 73rd annual convention of the Japanese Psychological Association (August 2009) will be hosted by the Ritsumeikan University!

My 2007's paper on tilt illusions published in the Japanese Psychological Research have got the top five! <September 13, 2008>

Kitaoka, A. (2007) Tilt illusions after Oyama (1960): A review. Japanese Psychological Research, 49, 7-19. PDF

Someone kindly let me know a novel illusion, called the "rotating grid" illusion. It's interesting! <August 25, 2008>

"Rotating snakes" has appeared in an in-flight magazine of Lufthansa. <August 12, 2008>

The PDF of Hisakata and Murakami's paper on the "Rotating snakes" illusion is now available from them. <August 8, 2008>

Hisakata, R. and Murakami, I. (2008) The effects of eccentricity and retinal illuminance on the illusory motion seen in a stationary luminance gradient. Vision Research, 49, 1940-1948.

Rumi's page --- Ikuya's page

Illusion contest will be held in Japan, too! It will be a formal contest in the 2009 meeting of the Japanese Psychonomic Society (Kiso-shinri-gakkai). <August 4, 2008>

The Thatcher illusion using the face of Professor Takao Sato, the president of the Japanese Psychonomic Society, is displayed in this poster.

A paper using the "Rotating snakes" illusion has appeared on line!

Beer, A. L., Heckel, A. H. and Greenlee, M. W. (2008) A motion illusion reveals mechanisms of perceptual stabilization. PLoS ONE, 3(7): e2741, 1-7. doi:10.1371/journal.pone.0002741 Freely available online

<August 1, 2008>

"Rotating snakes"

Circular snakes appear to rotate 'spontaneously'.

Copyright A.Kitaoka 2003 (September 2, 2003)

Explanation of the elemental illusion (optimized Fraser-Wilcox illusion) (PDF)

The image of the fractal spiral illusion was first published in a paper (Arai, 2008). <July 23, 2008>

Arai, H. (2008) Mathematical models of vision and wavelet. Suuri-kagaku (Mathematical Science), 46(8), 64-69 (in Japanese).

The image below is reproduced from Illusion designs from friends #5.

"Fractal spiral illusion"

Concentric rings made up of fractal islands appear to form spirals.

Copyright Hitoshi & Shinobu Arai 2007
from Professor Hitoshi Arai, Graduate School of Mathematical Sciences, University of Tokyo, October 4, 2007

A new illusion book "Trick Eyes Mechanism" will soon be published. <July 18, 2008>

(in Japanese)

An error hidden in the image shown below was corrected. <July 12, 2008> The latest works 33

"Four cards"

It appears as if there were blue and green gratings, though they are of the same color.

Copyright Akiyoshi Kitaoka 2008 (July 7)

Albert pointed out that the apparent blue and green gratings are really different in color. This error occurred in the downsizing process with antialiasing.from the high-resolution (giant) bitmap (12000 x 4957 pixel). The image shown below is an image without antialiasing, in which the gratings are just the same color (R = 0, G = 255, B = 151). <July 12, 2008>

The image shown below might be better, in which the gratings are just the same color (R = 0, G = 255, B = 150). <July 12, 2008>

A paper on the "Rotating snakes" illusion has been accepted for publication in Vision Research! <June 21, 2008>

Hisakata, R. and Murakami, I. (2008) The effects of eccentricity and retinal illuminance on the illusory motion seen in a stationary luminance gradient. Vision Research, in press

Rumi's page --- Ikuya's page

Related references

Chi, M-T., Lee, T-Y., Qu, Y., and Wong, T-T. (2008) Self-Animating Images: Illusory Motion Using Repeated Asymmetric Patterns. ACM Transaction on Graphics (Proceedings of SIGGRAPH 2008), 27, No.3. SIGGRAPH2008 --- Authors' page --- PDF (SIGGRAPH)

Scientific American Reports Special Edition on Perception (2008).

Kitaoka, A. and Ashida, H. (2007) A variant of the anomalous motion illusion based upon contrast and visual latency. Perception, 36, 1019-1035. PDF request to Akiyoshi Kitaoka

Newton Press (Ed.), A. Kitaoka (Supervisor) (2007) Newton magazine book: Special issue "How is the brain deceived? Perfect demonstration of visual illusions" Tokyo: Newton Press (in Japanese; published in October 2007). 

Ramachandran, V. S. and Rogers-Ramachandran, D. (2007) A Moving Experience: How the eyes can see movement where it does not exist. Scientific American Mind, February/March, 14-16.

Kitaoka, A. (2007) Phenomenal classification of the “optimized” Fraser-Wilcox illusion and the effect of color. Poster presentation in DemoNight, VSS2007, GWiz, Sarasota, Florida, USA, May 14, 2007.

Murakami, I., Kitaoka, A. and Ashida, H. (2006) A positive correlation between fixation instability and the strength of illusory motion in a static display. Vision Research, 46, 2421-2431. PDF request should be sent to Dr. Murakami

Kitaoka, A. (2006) Anomalous motion illusion and stereopsis. Journal of Three Dimensional Images (Japan), 20, 9-14. PDF (manuscript but the same as the printed one)

Kanazawa, S., Kitaoka, A. and Yamaguchi, M. K. (2006) Infants see the “Rotating Snake” illusion. Dorsal and ventral streams in the visual system (Talk): Monday, 21 August 2006; 12:00-12:30 (29th European Conference on Visual Perception, St-Petersburg, Russia, 20th-25th August, 2006) Abstract

Kitaoka, A., Ashida, H., and Murakami, I. (2005) Does the peripheral drift illusion generate illusory motion in depth? Journal of Three Dimensional Images (Tokyo), 19, 6-8. PDF (scanned copy) (poor quality) --- MS-Word file (manuscript, the same as the paper) (high quality)

Conway, R. B., Kitaoka, A., Yazdanbakhsh, A., Pack, C. C., and Livingstone, M. S. (2005) Neural basis for a powerful static motion illusion. Journal of Neuroscience, 25, 5651-5656. PDF request should be sent to Dr. Conway

Backus, B. T. and Oruç, I. (2005) Illusory motion from change over time in the response to contrast and luminance. Journal of Vision, 5, 1055-1069.

Kitaoka, A. and Ashida, H. (2003) Phenomenal characteristics of the peripheral drift illusion. VISION (Journal of the Vision Society of Japan), 15, 261-262. PDF

Naor-Raz, G. and Sekuler, R. (2000) Perceptual dimorphism in visual motion from stationary patterns. Perception, 29, 325-335.

Faubert, J. and Herbert, A. M. (1999) The peripheral drift illusion: A motion illusion in the visual periphery. Perception, 28, 617-621.

Fraser, A. and Wilcox, K. J. (1979) Perception of illusory movement. Nature, 281, 565-566.

Ben sent me a T-shirt. <May 30, 2008>

("2003" is correct.)


The "Best Visual Illusion of the Year Contest" Gala (May 11th, 2008, Naples FL, Philharmonic Center for the Arts) was a huge success, with more attendees than ever! This event was the fourth annual edition of the "Best Visual Illusion of the Year Contest". Previous editions drew numerous accolades from attendees as well as international media coverage.

The TOP THREE winners of the 2008 "Best Visual Illusion of the Year Contest" are:

- 1st PRIZE: Rob van Lier and Mark Vergeer (Radboud University Nijmegen, The Netherlands) -- "Filling in the Afterimage after the Image"
- 2nd prize: Rob Jenkins (University of Glasgow, UK)-- "Ghostly Gaze"
- 3rd prize: Thomas Papathomas (Rutgers University, USA)--"Rolling Eyes on a Hollow Mask"

The 2009 contest (5th annual edition!) will be hosted on May 10th, at 7pm (Philharmonic Center for the Arts, Naples, Florida). Illusion submissions for the 2009 contest are now being accepted!

Check out the WINNING ILLUSIONS, and all TOP TEN finalists at:

The winners took home a "Guido", a trophy designed by the renowned Italian sculptor Guido Moretti.

If you took PICTURES or VIDEOS of the event, please send them to us and we will post the best ones!!

This event was hosted by the Neural Correlate Society, a non-profit organization whose mission is to promote public awareness of neuroscience research and discovery, and sponsored by the Mind Science Foundation.

As the Platinum Sponsor of the "Best Visual Illusion of the Year Contest", the Mind Science Foundation is featuring complimentary visual illusion eCards at

On behalf of the Neural Correlate Society,

Susana Martinez-Conde (Executive Director and Illusion Contest Coordinator)

Neural Correlate Society Executive Committee: Jose-Manuel Alonso, Stephen
Macknik, Luis Martinez, Xoana Troncoso, Peter Tse

<May 27, 2008>

Professor Arthur Shapiro, Bucknell University, has opened his illusion blog! Click here. <May 25, 2008>

A Rotating snakes image has decorated a cover of Scientific American Reports! <May 19, 2008>

Thanks to So, Ikuya and Rumi

A review on perceptual research of Gestalt psychology in Japan has been published in Gestalt Theory! The authors are (the late) Kaoru Noguchi, Akiyoshi Kitaoka, and Midori Takashima. <May 1, 2008>

Noguchi, K., Kitaoka, A., and Takashima, M. (2008) Gestalt-oriented perceptual research in Japan: Past and present. Gestalt Theory, 30, 11-28. PDF request to me

The figures are available from here.

In this paper, as shown below, we proposed an explanation of the paradoxical figure-ground stability shown in the watercolor illusion (Pinna, 1987; Pinna et al., 2001) in terms of "unique transparency" (Adelson and Anandan, 1990; Anderson, 1997) in the study of achromatic transparency.

Figure 7. Watercolor illusion and apparent transparency. (a) The watercolor illusion. The corridor area appears to be tinted orange, to be veiled, and to be figure. (b) Achromatic watercolor illusion. The corridor area q appears to be veiled, to be darker than the surround b though they are the same in luminance, and to be figure. The alphabets a, b, p and q correspond to those shown in (c) or (d). (c) A possibly novel image of apparent transparency. It appears that a black square bearing a square window in the center is placed on the white background, and that a translucent disk appears to be in front of the black square and to cover the window entirely. The disk always appears to be transparent in front, i.e. unique transparency (Adelson and Anandan, 1990; Anderson, 1997). (d) Metelli's figure demonstrating  unique transparency. The disk always appears to be transparent in front.

Illusion news 9 (February 2008 - April 2008)

Illusion news 8 (November 2007 - February 2008)

Illusion news 7 (September 2007 - October 2007)

Illusion news 6 (June 2007 - September 2007)

Illusion news 5 (January 2007 - May 2007)

Illusion news 4 (January 2006 - December 2006)

Illusion news 3 (January 2006 - May 2006)

Illusion news 2 (April 2005 - December 2005)

Illusion news 1 (2002 - March 2005)

Akiyoshi's illusion pages