The YouTube video below is doing the rounds. It is of a kitten that supposedly is experiencing the illusory motion in Akiyoshi Kitaoka’s beautiful Rotating Snakes illusion.
Perception and the nature of illusions are my passion. So the question of whether animals, like this kitten, might also experience visual illusions is a fascinating one. Moreover, Kitaoka’s Rotating Snakes is one of my favourite illusions and features in the Illusions Gallery that I developed for the science museum I work for.
Rotating Snakes illusion by Akiyoshi Kitaoka
Although several sites (Boingboing, Popsci, io9) have posted this video, encouraging the public to test this illusion on their cats, they have forgotten an important prerequisite for good science: a control condition.
The fact that the kitten in this video interacts, attacks, teases, and plays with the image is not necessarily evidence that it is experiencing the illusory motion inherent in Rotating Snakes. For such a conclusion, you need to compare the cat’s behaviour to a control condition in which the cat views a similar image that contains no such illusory motion. If it seems uninterested and does not interact or play with the control image, you could infer that the cat might indeed be experiencing the illusory motion in the Rotating Snakes illusion.
Akiyoshi Kitaoka was kind enough to provide such a control image, so now we have the ingredients necessary to test whether cats might be experiencing the Rotating Snakes illusion.
So, cat owners, help collect data on whether cats are fooled by visual illusions. And please share this post and encourage other cat owners to take part in this experiment.
Here’s what to do:
- Click on Kitaoka’s link: http://www.psy.ritsumei.ac.jp/~akitaoka/rotsnakes15e.html
- Download and print the first two images of his Rotating Snakes illusion: the first one will rotate in front of your eyes (experimental condition), the second one will not (control condition).
- Set your camera or smart phone on <record> and get someone to start filming.
- Present the non-rotating version to your cat first, flat on the floor: tape it to the floor so that it doesn’t move around when touched.
- Allow a minute and a half of experimenting, then stop.
- Now tape and present the rotating version to your cat and film for another minute and a half.
Is there a difference in the cat’s behavior when viewing the non-rotating versus rotating version (more clawing, attacking, playing… like the kitten in the original video)?
Please post your comments and observations here, and preferably a link to your video!
Long live crowd-sourced science 😉
Diana
The Playful Mind 
I did this experiment on my housemates’ cat, but he was more interested in licking his bum! The only way I could get him to show any interest in either image was to move the paper around, but the actual illusion didn’t seem to hold any interest for him.
Thanks, Keith, for taking part!
I did this experment on my 2 cats. They first reacted to the the paper with illusion like they would do with a blanc paper, smelling it for a bit. I had to use snacks and toys to attrack further attention to the paper. They did not show any interest in the illusion.
Thanks for taking part, Elles!
I also took part! Tried both the illusion and the control condition on both my cats. I couldn’t explain to my oldest one that she had to look at the paper instead of sitting on it, but there was definitely some response(albeit not like the kitten in the video) in my younger cat in the experimental condition, compared to the control condition. I uploaded both videos so you can see it for yourself: the experimental condition can be found here(http://www.youtube.com/watch?v=uem0BLTQCZo&feature=youtu.be) and the control condition here (http://www.youtube.com/watch?v=d8uh6BLAOFc&feature=youtu.be). Note how, in the experimental condition, at the end, something on the paper does seem to have attracted my younger cat’s attention.
Hi Alexander,
Yes, your cat in the experimental condition does seem to be attracted by the image (from 1.00 onwards, it seemed to me). Her ears perk up and s/he seems to focus on the paper. Her reaction to the illusion version looks different than non-illusion version, in which she hardly looked at the paper. Interesting. Thanks so much for taking part in the experiment! I’m not surprised, seeing you are a psychology student ;-)! Maybe you can earn a point in one of your classes with this :-). Best, Diana