Spinning Dancer

So Cari shared this optical illusion with me: The Right Brain vs Left Brain. Before reading the article’s content, I’d like you to first stare at the spinning dancer and see if she’s going clockwise or counter-clockwise.

You can also see the dancer here:
spinning dancer
Click image to start animation or view it in the gallery.

If you could comment which orientation you first saw it in, I’d like to collect some statistics.

Most people I know saw her originally as spinning clockwise, which leads me to think the right brain vs left brain thing doesn’t really make sense, since most of the people I work with I would say are logical and math/science based instead of “uses feelings”. Then again, I’ve been able to get the dancer to swap orientations, so what does that say about me? What does it say about those who can swap them easier than others?

Anyway, if you want to get her to swap, we found staring at the legs and focusing at shadow helps. Sometimes closing your eyes for a bit or looking away helps too.

What’s happening here is that there is very little hints for depth perception, so the brain doesn’t really know which leg is in front of the other. If you truly believe that the dancer is only spinning in one direction or think that the animation is really just randomly switching directions on you, I’d like to give you the following 2 images:

Clockwise:
clockwise spinning dancer
Click image to start animation or view it in the gallery.

Counter-clockwise:
spinning dancer
Click image to start animation or view it in the gallery.

The 2 images above contain all the frames from the original and the frames are in the exact same order, but I’ve added some lines to help with the depth perception. If you think I’ve just reversed the order, then I’d bring you to my final animation:

all spinning dancer

By having these side by side, where the middle one is the original, it is now a lot easier to switch the orientation of the original. What’s that old saying? Don’t always believe what you see? ;p

One thing I noticed that’s different between the 2 spinning orientations is that the dancer is spinning on different legs. When she’s spinning clockwise, she’s spinning on her left foot. When she’s spinning counter-clockwise, she’s spinning on her right foot.

Xyon did point out that the shadow does align correctly with the counter-clockwise spinning, and maybe that’s why they decided that people who are logical would see her spinning counter-clockwise. But the experiment seems quite lacking and no justification was really given, so I’d wouldn’t say what they’re claiming is definitive.

18 Comments

  1. ångel said:

    Other people are pretty sure it has nothing to do with “brain handed-ness” either: http://www.newscientist.com/blog/shortsharpscience/2007/10/bring-on-dancing-girl.html

  2. Hank said:

    Looks clockwise to me. I can’t get perceive it the other way except by catching it in the corner of my eye for a split second.

  3. Dave said:

    Good Job. I was able to get her to switch directions in my brain by concentrating on her foot. But… Then I would blink and she would be going counter clockwise again.

  4. Ed Darrell said:

    Nice work to show how the illusion works. Thanks for dropping by the Bathtub to let us know.

  5. Rebecca said:

    Indeed. Very nice work on dissecting the image and I thank you, too, for stopping by rebeccahartong.net with a link to your work. Nice!

  6. dj said:

    just amazing. I really appreciate the animation with all three dances — one with lines defining clockwise, the original, and finally one with lines defining counterclockwise.

    I was only able to see it clockwise until I saw the line drawings allowing me to see the switch in perspectives.

    after that I was able to view it both ways.

    Is there some chart that shows statistically how people perceive it? I don’t see how people could see it as anything other than a clockwise spin at first.

  7. Andrew said:

    excellent work!

    I was fiddling with her unraised foot rotating in the opposite direction and your perspective makes this easier. I then briefly can rotate her head in the opposite direction.

    Any chance of a version with different parts having different perspective so it all rotates differently please?

    Thanks

  8. Krunk said:

    Haha! I’ll see what I can do. Probably won’t have time till this weekend.

  9. heater said:

    I first saw her going counter-clockwise as viewed from above. As I stared at it, she started oscillating, always facing forward. Interesting. Nice analysis.

  10. Daniel Richard said:

    Woah, It required me to view the line perspective to turn it from clockwise to counter clockwise. Or else I’d be watching it spin in the clockwise direction forever. :D

  11. A.J. said:

    Wow, that’s really cool. At first I could only see her spinning counter-clockwise. After looking at the version with the lines that force you to see her spinning clockwise, I was able to see the original spin either way, though I needed to blink to get her to “change” directions.

  12. Nick said:

    Thank you!!! I seriously could not get it until your explanation. Now I will be able to sleep tonight (beer will also help).

  13. Dave said:

    I can easily make her go anti-clockwise by simply hitting refresh on my browser! Its a daft trick – th animation changes – time it and see it changes at the same point each time and is reset by hitting refresh. You people are seriously gullable.

  14. soylatteQT said:

    she always looks as though she is spinning counter-clockwise. no matter how hard i try i can’t get her to spin the other way…

  15. Vremmi said:

    Excellent explanation to the original version http://www.shamozzle.com/RightLeftBrainTest.html which has been tripping my mind, thanx heaps Krunkster :)

  16. justis chase said:

    The reason that most people see the dancer in right brain mode when they first look at it is because almost everyone uses the right brain to process images. So even a very strong left brain person will use their right brain initially. If they have internal dialog then they will almost immediately switch to the left brain and the dancer will change direction. If they focus on the image they will get right brain activity, if they start to speak, or use language, (reading etc) most times it will switch to left brain activity again.

  17. christine said:

    totally mental, I managed to get two to turn one way and one the other than flipped them over wonder what that means. well done.

  18. Andrew said:

    Thank you for painting the ass on the top of that woman :P I could only see her spin clockwise and couldn’t get her to switch no mater what! But that picture helped and I finally saw her move counterclockwise as well.

Leave a Reply