The Spinning Dancer and the Brain

spinning dancer illusion This image, originally created by Nobuyuki Kayahara, is a great scientific personality test. If you see the dancer spinning clockwise, you’ve got excess spleen qi in your left frontal crockus. This means that you’re a vibrant personality whose passions are apparent to everyone around you, but sometimes you are indecisive. If you see her spinning counter-clockwise, the right ascension of your natal chart lies in your sagittal broab and there are Fire humours dribbling out your left nostril. You should see a doctor as soon as possible.

An Australian tabloid recently republished the dancer with a little spiel about how you can use her spin as an indication of whether you are right-brained or left-brained. Since then, she’s propagated all over the internets, and so has the accompanying spiel.

In contrast to my deeply insightful, completely factitious interpretations of the left frontal crockus, the tabloid’s claims about “left brain” and “right brain” personality types are vastly overblown. But the spinny dancer is captivating, and because we are watching her with our brains in addition to our eyeballs, she must surely tell us something about how our brains work… so what’s actually going on?

As it happens, my fiancé is a professional optical illusion geek. He spends his time making monkeys play video games, in order to figure out their visual processing systems. So I made him explain it to me.

This much is true: you process some visual stimuli on the right side of your brain, and some on the left. You also have two optic nerves, one from the back of each eyeball. On their way to the brain these nerves meet up in a location called the optic chiasm. From the optic chiasm, information about the left side of your field of view, no matter which eye it’s coming from, is sent to the right hemisphere of your brain to be processed. Information about the right side of your field of view is sent to the left hemisphere. Therefore, if you want to see what your right brain makes of the dancer, you just need to look over to her right and watch her from your peripheral vision. Looking to her left will show you the left-brained view.

After a little practice, I can get the dancer to switch between clockwise and counter-clockwise spins – from either side of my visual field. This means both sides of my brain see both directions of spin just fine. This effect doesn’t have anything to do with differences in visual processing by the right and left sides of the brain.

Actually, the spinning dancer is an example of something called bistable perception. As an object that can be seen in either of two ways, it’s in the same class of illusion as the Necker cube and the face-vase.

Your visual system has evolved to construct a reasonable mental image of the world with a limited amount of information, and it uses a dizzying array of assumptions to do so. In the natural world these assumptions are mostly valid, and there’s only one right way to interpret any given set of signals. Artists and sundry neuroscientists, however, can consciously exploit the assumptions your brain makes about the objects it’s looking at to produce images with two or more equally valid interpretations.

When presented with stimuli that have two valid, mutually contradictory interpretations, your brain just picks one. Then, sometimes, it picks the other. We still don’t understand why this happens, or what role conscious efforts might play in this shift in perception. Many people are able to make the dancer shift directions at will, but the strategies I’ve seen almost always invoke a change of focus – I shift my attention to her feet, or scroll up and down, others look at her hands or to her side. (I’ve also seen lots of people talk about staring at her nipples, but none who report that it helps them see her change directions.)

There is absolutely nothing special about what your brain is doing when it takes some funny black shapes and turns them into a dancer who spins in both directions. Bistable stimuli are resolved using the exact same neural circuitry as everything else, and you can prove it by sticking electrodes into monkeys’ heads (e.g., Grunewald et al., 2002). You could probably prove it by sticking electrodes into your own head, too, if you felt like it. Bistable images are useful tools for experiments, because they allow us to isolate the part of visual processing where the brain is actually making a decision about how to interpret an image from the parts that are purely determined by the action at the back of your eyeball.

Bistability is not just a visual phenomenon, either – there’s an audio version called the tritone paradox. * If humans had less wimpy olfactory processing, I’m sure we could figure out some bistable smell illusions, too – though as far as I know no one has tried to confuse dogs with this particular technique.

If this explanation hasn’t been technical enough for you, try this review paper by Parker and Krug.

* The way you perceive the tones in the tritone paradox is strongly related to your native language and the region in which you grew up. It’s harder to switch your perception of this paradox than it is to switch with most visual illusions, but after listening a couple times and paying attention to the overtones, I could hear the second pair of tones in the other direction.

There are lots of cool audio illusions to play with if you poke around that site. This one, which ostensibly induces your brain to pick out words related to things it has been dwelling on lately, is depressing – I default to hearing the words “no way” repeated over and over. But if I move my speakers around a little I also start to hear “burp”, “rainbow”, “wanker”, and the name of the guy in the office next door. I think I’ll stick to interpreting my dreams instead.

Trackbacks & Pings

  1. The Spinning Dancer Explained » Manolo's Shoe Blog: Shoes, Fashion, Celebrity, and Manolo! on 20 Oct 2007 at 8:42 pm

    [...] It turns out that the actual explanation of why she seems to spin one way, and then the other, is much more interesting. [...]

  2. Official GMD Social Thread - Page 225 - Ultimate Metal Forum on 21 Oct 2007 at 8:06 am

    [...] this online today. It’s brain test. Which way does the dancer spin for you? Article here __________________ Escorted by a thousand souls Remembered but still [...]

  3. Strange! - Personal Development for Smart People Forums on 21 Oct 2007 at 8:15 am

    [...] this interests you – there is more information about optical and auditory illusions here: The Spinning Dancer and the Brain he better explains this illusion and why you see her spin in the direction that you do. [...]

  4. greg hughes - dot net - Are you right- or left-brained? on 23 Oct 2007 at 8:18 am

    [...] stuff is hooey, and you can see why it must be with a little knowledge of neural anatomy and a simple experiment.yamiTuesday, 23 October 2007 08:00:24 (Pacific Daylight Time, UTC-07:00)@Yami – thanks for the [...]

  5. Spinning Dancer Brain Optical Illusion on 05 Nov 2007 at 7:56 pm

    [...] See more of the explanation from Gabbro. [...]

  6. ??????? ?? ?? ?????? - Page 4 - AKB Forums on 03 Dec 2007 at 7:38 am

    [...] ? ??? ??????- ??????, ? ????? ?????? ???-???? ?????? ? ????????? ??? ?? ????? ?????????? ????????: The Spinning Dancer and the Brain C??? ??????: ???? ???????? ?????? ? ??????????????? ???????????? ???????. ??????, ???? ??? [...]

  7. You spin me right round, baby; right round « Snapshots of a… Crazy Kinda Life on 29 Jan 2009 at 6:41 pm

    [...] want it to be, but if you are curious as to why she can be seen spinning in both directions at once check out this article, or this NY Times article, or the Wikipedia article. (And if you need it explained in plain [...]

  8. The Spinning Dancer | Tyge Mortensen on 31 Jan 2010 at 11:57 pm

    [...] Hvis man stirre tilstrækkelige længe på hende, vil hun begynde at snurre den modsatte vej rundt. Måske. Nogle får hende til at skifte retning ved at kikke på brystvorterne, andre på skyggerne. Men det har ikke noget med din hjernehalvdel at gøre (kilde). [...]

  9. The Spinning Dancer | Sounds Like Life to Me on 17 Feb 2010 at 12:06 pm

    [...] way can you make the Spinning dancer go?? Go to this link and see for yourself! Feel free to leave a comment after you try this [...]

  10. The Spinning Dancer | murhardiningtyas on 28 Mar 2011 at 3:45 am

    [...] 1 The spinning dancer and the brain. http://greengabbro.net/2007/10/20/the-spinning-dancer-and-the-brain/ [...]

  11. The Spinning Dancer « Neuroscience in Action: Section 4 on 28 Jul 2014 at 6:51 pm

    […] sources: http://greengabbro.net/2007/10/20/the-spinning-dancer-and-the-brain/  http://www.sciencedirect.com/science/article/pii/S0959438803000990 […]

Comments

  1. Kent wrote:

    I find it interesting how nobody specifies whether the spin direction is when viewed from above or below.

  2. Mad Hatter wrote:

    How cool! I love optical illusions and found this one mesmerizing. I actually see the rotation both ways–if I just look away for a few moments and then look at it again, the dancer will have switched from one direction to the other. But I can’t seem to make it switch on purpose….

  3. mithua wrote:

    The dancer’s spinward arm is raised. If that changes with the direction of spin, then this whole presentation seems bogus.

  4. mithua wrote:

    …and of course you can change the direction of the “spinning” by clicking on your scroll bar– sometimes once, sometimes twice, three or four times will do the trick. That way you can stop the image and see that when it changes direction it mirrors the previous image.

  5. Jessica wrote:

    If you look at it indirectly, then look directly at it when its leg it pointed to one of the bottom corners, it tricks your eye to think that it is switching direction. Do it over and over and it just looks like the dancer is turning to its left and right, not in a circle…..pretty nifty.

  6. Andrew Ironwood wrote:

    I can’t get it to go clockwise to save my life — but then, being borderline autistic and hardcore INTJ might have *something* to do with that, yes? [grin]…

  7. Andrew Ironwood wrote:

    Scratch my previous — on my home monitor, it switches (dernded cheap work monitor, anyhoo [grin]…)

  8. Dillo wrote:

    You can prove the “Your brain just picks one” statement by clicking on the scrollbar in your browser and dragging the page up and down slightly. This forces the animation in the window to freeze or halt on certain frames, moving the scrollbar in the opposite direction gives it enough time to start up again for a frame or two. While not at all scientific, I would say my simply messing with the animation in this way results in an apparent 50/50 split between going clockwise vs. counter-clockwise.

    It really is all just an illusion. We are very, very complex mechanisms, but mechanisms nonetheless.

  9. captain banana wrote:

    The shadow seems to blow the illusion off… If she were to be spinning counter-clockwise, we’d see the shadow appear at her opposite side of rotation.

  10. Hob wrote:

    It seems a little different than the Necker cube because it doesn’t just have ambiguous cues, it has cues that are *wrong* either way. Whichever hand/foot you pick to be in “front”, it doesn’t get bigger when it’s closer and smaller when it’s farther away – it gets a little smaller when it’s either near or far, and big when it’s on the side. And the shadow doesn’t behave like a shadow would no matter which way she’s rotating; it looks like they just took the 2-D image and flipped it 180 degrees, and moved them both up and down kind of randomly.

  11. Krunk wrote:

    I’ve added some extra lines to help with the depth perception:

    http://www.krunk4ever.com/blog/2007/10/17/spinning-dancer/
    http://gallery.krunk4ever.com/v/Animated_Gifs/all-spinning-dancer.gif.html

  12. Lab Lemming wrote:

    Is this the same visual picking that turns craters into mesas and rivers into ridges in aerial photos?

  13. Anonymous wrote:

    The real reason why you can see her spinning both directions: http://www.shvoong.com/internet-and-technologies/1695919-optical-illusion-right-brain-left/

  14. Scot wrote:

    Although I can see her spin both directions, her shadow or mirror image, or whatever it is that is below her doesn’t make sense if she’s turning to the right. The way her shadow moves when she turns to the right isn’t possible. When she turns right, her foot and the shadow move to the left right? Right. But her shadow would keep revolving around her left foot on the opposite side of her instead of moving out of the picture. When you look at her turn left you can see that the shadow makes sense.

  15. Mikey2 wrote:

    Of course this is an oversimplification, but I do think there is something to this test that shows imagination:

    Which do you automatically assume? Is she floating in a void with the light-source behind her? [clockwise] or is she against a 2-d wall with the light behind the viewer? [counter-clockwise]

    Of course anything like this is an oversimplification and not “scientific” …but it may provide *some* insight more than a mere illusion.

  16. Tokuwuwoh wrote:

    The rotation direction can be controlled with a technique, its a surefire. Find out in this web site:

    http://www.wefooleffect.com/WFE%20on%20optical%20illusion.htm

  17. Anonymous wrote:

    Here’s a better illustration of hot the image was created:

    http://gallery.krunk4ever.com/v/Animated_Gifs/all-spinning-dancer.gif.html

    http://gallery.krunk4ever.com/v/Animated_Gifs/all-spinning-dancer.gif.html

  18. Flicka Mawa wrote:

    Thanks for this great explanation of what’s going on here. This makes a lot more sense than that it actually tells you if you’re left brained or right brained.

  19. jonho wrote:

    http://anuragworld.googlepages.com/mysteryofthespinningdancer has a very lucid description of what is causing the illusion. It also has a trick to help those who see the dancer spin only in one direction

  20. borneo wrote:

    couldnt make it spin counter-clockwise so i turned my monitor upside-down and voila – its spinning counter-clockwise :)))

  21. borneo wrote:

    nice optical illusion, i had actually to cover the legs, watch torso only, not looking directly at the picture but having it in my peripherical sight. then i was able to switch the spinning direction. as soon as i uncovered the legs and shadow, it was spinning clockwise again.

  22. Shuda wrote:

    Proberly the best thing ever.

  23. Andrea wrote:

    I found that i can change her direction by blinking. It’s really easy for me to see her spinning left, it does get hard sometimes to blink and change the direction to the right. I don’t change my focus, move the screen or look anywhere other than where I was originally looking and I stare at the screen straight ahead!

  24. Lauren wrote:

    omg, its spins to the right around 10 times and then auto changes.. its not you.

  25. Carl wrote:

    I just like the her tits.

  26. Tania wrote:

    omd……….. i just made it move clockwise then anticlockwise on purpose hehe u have to be able to pretend that the shadow is going clockwise or anticlockwise to be able to change the way in which she is going!

    OMD this is so cool lol

  27. Cameron wrote:

    The pictrue shown is bogus she has to go in a couterclokwise direction (DUH).

  28. kathleen wrote:

    to make her change direction, i just have to blink and visual her spinning the other way. works every time.

  29. baconn wrote:

    Lauren, the direction is NOT changing. It’s an optical illusion. For some people, when they first see the dancer, they think she is dancing counterclockwise. It isn’t a trick.

    Cameron, huh? She goes in either direction. Not one. Her direction is ambiguous.

  30. Eduardo wrote:

    Es muy sencillo, solo tienes que mirar de reojo la imagen, y solo
    cambia el giro a voluntad de uno
    mismo, va y viene y voluntad
    propia, es muy divertido, me gusta mucho!!!!!!!!!!!!!!!!!

  31. monir hossain wrote:

    Lot of thanks for a great illussion for visible objects from eye sights

  32. RJB wrote:

    How about a little credit to the guy who actually created this illusion? Very clever. Somewhat strange to spend time on something like this, but clever.

  33. Jizzle wrote:

    You have got to be kidding me people.

    Copy the .gif to a forum, post it TWICE…and watch the image magically change directions AT THE SAME TIME.

    This is bogus, and I cant believe how many of you fell for it.. quite sad.

    Go Bills.
    Peace.

  34. Annie wrote:

    omg that is sooo cool. what happens if you see her both ways??

  35. RJB wrote:

    Annie…it means the hemispheres of your brain are switched, with the left hemisphere where the right should be, and the right where the left should be. Or your hemispheres are correctly placed, but your eyeballs are switched. You should consider seeing a doctor and having them switched back.

  36. Tim wrote:

    We’ve just had a brilliant argument about this in the office. “No, it’s moving clockwise!” – “No, it’s not, it’s anti-clockwise!”

    Brilliant to do with a few people. I saw her change directions many times, switching legs etc etc. Fascinating :)

  37. Geng Liu wrote:

    The illusiong is too simple.Clockwise or counter-clockwise depends on where are you. Look from the head,it is clockwise;and look from the feet,it is conter-clockwise. It cannot tell the difference of the brain.

  38. claire wrote:

    jessica’s method work, but i had to use the shadow at the start, the shadows make the dancer change sides at the left, i have no idea why

  39. t1op wrote:

    Whether you see the dancer moving clockwise or anti-clockwise depends on whether you choose to examine her axis from above or beneath.

    If you look at the turning axis from above that means she is turning clockwise. However, if you view the turning axis from beneath that means she is turning counter-clockwise.

    Test this: Point your index finger up and, at chest level, rotate your hand clockwise on the transverse plane (ie the floor or table represent transverse planes, your mirror does not).
    Now, still rotating the hand the same way, raise it above your head. It will now appear to be moving counter-clockwise.

    How the image works: First, the model leans back and rotates on a diagonal axis so that your view of her rotates between slanted downward and slanted upward. Second, the model is moving up and down. Depending on which up-down slant or up-down movement you unconsciously fix on either the above or below perspective of the turning axis.

  40. JC John SESE Cuneta wrote:

    @Jizzle: Of course it will change directions twice. Your brain cannot process two optical illusions, much more THE SAME optical illusions, twice. You can only process one.

    If your brain can see two or more similar optical illusions like that one, moving in counter and clockwise, then you are not from this Planet.

    If you think it is “timed” then do this:
    1) Duplicate the image yourself; or
    2) Write down in a piece of paper the number of minutes each direction changes occured to you;
    3) Repeat #2 up to 5 times.
    4) Compare your results.

    You will see that you have different time span for each directional switch of the girl.

  41. jamaica wrote:

    w0w, i see it rotating clockwise, but i can also control it and see it spin counter-clockwise,..

    do that mean anything?

  42. onno wrote:

    Its a front and back issue, for in drawing, one requires overlap to help force things into distance, but in this image, there is no clue as to what is front or back, so your brain has to make an assumption, and both assumptions are similarly compelling. The switch happens because you switch which arm/leg is overlapping the other. Since there is no visual indication, it can go either way, at first like magic, then once you understand, whatever your preference.

  43. steph wrote:

    omg this is kreepy
    so if i see it both directions do i have stuff leaking out of my nose?
    is it true that ur married to a science geek?
    do you think that im a 12 year old?
    cuz i am

  44. robert wrote:

    took me about 30 seconds to get the change in direction going.
    had a closer look at it and worked out how it works.
    its a matter of perspective.
    the image is not 3D and because it is black you cannot tell wether you are
    looking at the front or the or the back of the girl,except when she is side on and
    when she is side on you cannot tell wether you are looking at her left side or her right side.
    so depending on which perspective your brain takes she will spin one way or the other.
    change your perspective and you change the direction.
    with a bit of practice you can change her direction every half rotation.

  45. cici wrote:

    this is fukin gay

  46. amy wrote:

    well that is becuse you did not look at it

  47. Ryan Husman wrote:

    am i the only one who sees the leg spinning one direction and the body spinning in anoher direction?

  48. Abdul wrote:

    I checked this out a while ago, surprisingly I can get my mind to view it both ways. I first saw it moving clock-wise, I focused a bit and saw it moving couter-clock wise. Still a pretty interesting thing though. :)

  49. Elizabeth wrote:

    @ Kent, the image is not actually spinning its moving from side to side. that means that the spinning is all in your head. there is no right or wrong answer, and there is no view from above. oh and by the way, i can change which way its spinning on command now.

  50. Amal wrote:

    you cared me by advicing to go to the doctoe bcaz i m able to switch but most of the time i see it counter clockwise…

  51. Jules wrote:

    I have seen the dancer spin in both directions; it’s a matter of concentration. In fact, it helps to stimulate the brain with a few push-ups. After 20 push-ups, I regarded the image, and she spun clockwise. But after two mintues, she magically slipped into counter-clockwise. Visually, focus on her face in order to catch both directions.

  52. Heather wrote:

    If you concentrate on her face, not her leg then you can noticably see it switch directions, her head is leaning in the direction she is turning and you can see it jolt when it changes.

  53. ahoy wrote:

    i think the dancer is “being” made to change rotation and has nothing to do with illusion or right/left brain

  54. Shaly wrote:

    Hi

    this is actually fake … the image changes direction by itself … have a group of friends watch it with you … you’ll all notice the direction change at the same time (not your brain interpreting but the direction changing by itself)

  55. Kyla wrote:

    Weird… I was looking at her and she was spinning anti-clock wise and then I looked again and she was spinning clock wise!

  56. Indy wrote:

    There is no big deal about this. The person who created this, did so that the lady spins both ways. Nobody’s mind makes it goes into any different direction. It was made to switch directions intemitenly. Just another thing people come up with from time to time, to give the impression that their brain is working better than the rest of us. Try something better to fool me.

  57. joe wrote:

    fake

  58. jezz wrote:

    I wonder if the rotation is fixed for me because I am continually distracted by the nipples?

  59. TMM wrote:

    the best way to see the different directions is looking at the heel/foot

  60. bella wrote:

    why can’t I make this rotate clockwise? I can only perceive it rotating anti-clockwise, staring at it too long makes me nauseous :(

  61. Craig wrote:

    Cool stuff

  62. Tia wrote:

    There is NO optical illusion here.The animation spins one way for a period of time and then the other,and then at different time intervals.

    You can do this with your own hands.Pretend that you are opening a large bottle cap.Rotate many times one way to open the cap then without pausing rotate to close the cap.Your hand goes left to right and right to left in both cases i.e they are always moving in opposite directions but it is the ‘jerk’ on either direction(when either opening or closing) which gives the illusion of clockwise movement or anticlockwise movement.

  63. Bruno wrote:

    5.Jessica wrote:
    “If you look at it indirectly,…”
    Look close, you can see her swtiching legs too.

  64. Anthony wrote:

    I see her change direction occasionally.
    What does this mean ?

  65. kalyan upadhyay wrote:

    ow!!

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