Silhouette pirouette

October 8, 2007 8:00 PM

Is the dancer spinning clockwise or counterclockwise? An optical illusion.

Ignore the right brain/left brain gobblydegook.

posted by painquale (133 comments total)

If you say the dancer is spinning counterclockwise, then you're a dirty dirty liar.
posted by item at 8:03 PM on October 8, 2007 [5 favorites]

After watching this image rotate clockwise for several minutes, it seems like the direction reversed. I could not figure out how it should be moving in the opposite direction and yet still look the same. After another minute it switched direction again.
posted by semantic scope at 8:05 PM on October 8, 2007

She was spinning clockwise for a while, but then she suddenly started spinning counter-clockwise.

This is one of the stranger illusions I've come across...
posted by WetherMan at 8:06 PM on October 8, 2007

well, she is obviously spinning counter-clockwise. she never changed directions for me, but I only looked for 15 seconds or so.
posted by ouchitburns at 8:08 PM on October 8, 2007

Look at the shadow for a few seconds — this will trick your mind into looking at her spin the other direction.
posted by Blazecock Pileon at 8:08 PM on October 8, 2007

well, I focused like crazy and she switched. neat.
posted by ouchitburns at 8:10 PM on October 8, 2007

I think this is a hoax.
posted by mert at 8:10 PM on October 8, 2007

WOW! ...lame.
posted by Balisong at 8:10 PM on October 8, 2007

Wait... she changed
posted by mert at 8:11 PM on October 8, 2007

It spins clockwise as seen from above, yet spins anticlockwise as seen from below; IT'S CRAZY!!!!!11!
posted by Tube at 8:11 PM on October 8, 2007 [2 favorites]

She's almost always spinning clockwise for me. I got her spinning counterclockwise by staring at her foot and imagining what would have to be the case for her to change directions, and then for a little while I was able to swap directions at will, but I seem to have lost that ability. Now she's just spinning clockwise forever and I've become nauseous.
posted by painquale at 8:11 PM on October 8, 2007

I just made it switch WITH MY MIND.
posted by hermitosis at 8:12 PM on October 8, 2007 [11 favorites]

When she's spinning clockwise, her right leg is raised. Counter clockwise it's her left leg.. Doesnt that mean it's a hoax?
posted by mert at 8:13 PM on October 8, 2007

I watched for about a minute and a half, and nothing ever changed for me. She spun clockwise the whole time. I even tried Blazecock Pileon's suggestion of looking at the shadow and she still didn't change direction.
posted by amyms at 8:15 PM on October 8, 2007 [1 favorite]

Neat. I too found it easiest to have her switch direction by focusing on the foot she's spinning on.

I don't think it's a hoax, I opened up the GIF file in ImageReady and it's just one revolution in 34 frames, repeating infinitely.
posted by good in a vacuum at 8:15 PM on October 8, 2007 [2 favorites]

When I focus on her left hand, I see her spinning counterclockwise, indicating that my left brain is functioning at a higher level.

When I focus on her shadow, I see her spinning clockwise, indicating that my right brain is functioning at a higher level.

When I focus on her boobs, my IQ drops 140 points and my brain shuts down completely.
posted by googly at 8:16 PM on October 8, 2007 [17 favorites]

Nope. Following the shadow didn't change anything either. I have to agree with item: You counterclockwise-ers are all liars.
posted by Weebot at 8:17 PM on October 8, 2007

always clockwise...
and i second googly's last line.
posted by ruwan at 8:18 PM on October 8, 2007

I got her to switch directions by closing one eye, blurring her as much as I could, and, like painquale said, thinking about her raised foot moving in the other direction.
posted by zachk at 8:19 PM on October 8, 2007

I'd guess the optical trick is that the direction she appears to be spinning is dependent on whether your brain thinks her outstretched leg is on the near side of her body, or the far side at a given moment. Since there's no shadows on her body to help determine depth, it's sort of a "do you see a vase or two faces" -type illusion.
posted by good in a vacuum at 8:20 PM on October 8, 2007

Yeah, her boobs are awesome.

Wait. She's turning?
posted by Brockles at 8:20 PM on October 8, 2007

I was able to go back and forth, with the power of my mind, but now I'm weirded out.
posted by jsavimbi at 8:20 PM on October 8, 2007

I don't see how anyone could perceive her spinning anti-clockwise.
posted by Malor at 8:21 PM on October 8, 2007

She's spinning any damn way I tell her to. Now if I can just get her to go to the fridge and get me another beer.
posted by ranchocalamari at 8:22 PM on October 8, 2007

In all seriousness, I default to counter-clockwise, but by focusing on her foot I can switch back and forth.
posted by googly at 8:25 PM on October 8, 2007

The exploratorium has a physical, 3d version of this (it looks like a picture frame).
posted by alexei at 8:26 PM on October 8, 2007

She spins clockwise for me until I start pondering the cause of the effect.
posted by bunnytricks at 8:34 PM on October 8, 2007

I started out counterclockwise, successfully switched her around a couple of times by looking at the shadow, then noticed she had nipples and lost my focus. I was going to send this to my niece to freak her out, but now I can't bring myself to do it. Nipples! OH THE HUMANITY!

(as it were)
posted by socratic at 8:34 PM on October 8, 2007

No matter how hard I try, I can NOT see her spinning counter-clockwise. *stomps and pouts*
posted by katillathehun at 8:35 PM on October 8, 2007

I was an unbeliever (clockwise variety) until I blocked my view of everything but her foot's shadow, closed one eye, and got it going counterclockwise. After that it took a few tries to see the whole dancer that way, but it did work, if only for a few seconds. Wow.
posted by dontoine at 8:35 PM on October 8, 2007 [1 favorite]

I could see her spinning either way pretty easily. That's pretty neat.
posted by The Great Big Mulp at 8:35 PM on October 8, 2007

Wait! I can! I can! I really can! IT'S WITCHCRAFT.
posted by katillathehun at 8:37 PM on October 8, 2007 [1 favorite]

Wow, that's crazy. I was totally convinced that she could only be going counterclockwise, but then I got it to switch. The foot is definitely the key...
posted by equalpants at 8:37 PM on October 8, 2007

i can't get it her to spin counter clockwise... to me it's just clockwise no matter how i look at it.
posted by jcruelty at 8:37 PM on October 8, 2007

This is driving me crazy. I haven't been able to focus enough to switch the apparent rotation from clockwise to counter-clockwise, so I blocked everything but the head with a sheet of paper. Eventually, that did start rotating counter-clockwise, so I unblocked a bit more. I was able to lower the paper until just the feet were uncovered without changing the apparent rotation, but once I could see the entire figure, BAM, clockwise.

Now I need some painkillers.
posted by agent at 8:38 PM on October 8, 2007

This is so irritating! She switched once and now won't switch back. If I hadn't seen her do it once, I wouldn't have believed it.
posted by rottytooth at 8:39 PM on October 8, 2007 [1 favorite]

It's a very cool illusion, and the key is that the two middle frames (when the bent leg is directly behind (or in front of) the body) can be seen either way. Which way you "interpret" those frames dictates whether you see the next frame as facing you or not facing you. Once you make that "decision", the rest fall like dominoes (we humans are pattern-seeing creatures) until your mind gets confused again, deliberately or not, and has to re-interpret and find a new pattern.

You'll only get a fresh re-interpretation if your brain starts figuring it out again from that one ambiguous frame.... and I'd guess that even then, you have a 50-50 (?) shot of interpreting it clockwise or anticlockwise.

Sorry for explaining the obvious. I've always liked this one. Those of you who give up after 15s should try again. For some people, it takes several minutes, but in my experience there's always a "holy crap!" moment eventually.
posted by rokusan at 8:39 PM on October 8, 2007 [2 favorites]

You gots to look at the feet, people!
posted by Reggie Digest at 8:40 PM on October 8, 2007 [1 favorite]

The shadow. I noticed that it didn't really look like her shadow was rotating so much as moving side-to-side, and now I can change her direction almost at will. (at least, that's how it worked for me)
posted by katillathehun at 8:40 PM on October 8, 2007

Yeah, it's the foot. Stare at it and you can perceive the change in direction.
posted by strontiumdog at 8:41 PM on October 8, 2007

Most of the time, she was spinning clockwise for me. Sometimes, she'd switch to counter-clockwise though. Very interesting. Thanks for posting that.
posted by whatideserve at 8:42 PM on October 8, 2007

you can make it switch in your head right when the two feet converge in the center
posted by strontiumdog at 8:47 PM on October 8, 2007

To make her spin in any direction, stare at the image for a few seconds, then close your eyes and imagine what she would look like spinning the opposite direction and open them again. Pretty neat.
posted by softriver at 8:49 PM on October 8, 2007

sorry for commenting so much but that is so cool. I am getting it to switch when the model rotates every 180 degrees.

this is trippy. Thanks for sharing painquale
posted by strontiumdog at 8:50 PM on October 8, 2007

haha! That works too softriver. I'm all left brain / right brain and shit.
posted by strontiumdog at 8:52 PM on October 8, 2007

Yeah, if you cover up everything but her lower foot, focus on it and imagine it going the way you want, then slowly reveal the rest of the picture, it'll switch. At least that worked for me.
posted by LogicalDash at 8:55 PM on October 8, 2007

Took me a minute, but when I stared at the food bouncing on the shadow I could eventually do the 180 deg. thing.
posted by carsonb at 8:56 PM on October 8, 2007

The crazy thing is not only does she appear to change directions, but her head tilts to opposite sides as well.
posted by itchylick at 8:58 PM on October 8, 2007

Being hosted from Australia, she's also upside down.
posted by hal9k at 8:58 PM on October 8, 2007 [2 favorites]

I'm part of the "I can switch her direction at will but then I get nauseous" crowd.

And my right eye won't stop twitching now. Thanks!
posted by gummi at 9:01 PM on October 8, 2007

She has switched twice, the first time after about five minutes, but I have no control over her whatsoever. I yell and yell and she just ignores me and spins whatever damn way she pleases.
posted by PhatLobley at 9:07 PM on October 8, 2007

This is weird and cool. I also got her to switch directions by staring at her feet. The trick behind it kind of reminds me of one of my friends, who while watching MST3k, used to swear that most of the time he thought Crow was facing away from the movie and towards the audience, but sometimes looked like he was facing the right direction.
posted by Venadium at 9:08 PM on October 8, 2007 [2 favorites]

I can flip her by looking at her foot, but it's not instantaneous.
posted by juv3nal at 9:11 PM on October 8, 2007

When the animation was still loading, it looked counterclockwise. Once it finished, and started moving at a constant (non-jerky) speed, definitely clockwise.
posted by Godbert at 9:11 PM on October 8, 2007

Use two hands, block out the shadow and everything above her ankle.

Watch the foot, you can kind of choose whether it's going clockwise or counterclockwise just as it crosses the middle. Move your hands away just as you feel yourself interpreting it a certain way.
posted by empath at 9:14 PM on October 8, 2007

Venadium, I thought the same thing. I swear he was facing away from the movie. I mean, it made sense, the movies were terrible, he didn't want to watch them...

Anyway, looking at the dancer, if I told myself she moved clockwise, she moved clockwise, and if told myself she moved counter-clockwise, she did. The feet thing didn't seem to have any effect, I just had to tell myself she moved in a certain direction and it happened. Showing my friend, all he stated was "she's hot". She only appeared to move clockwise for him. Now I have "Private Dancer" playing in my head on repeat...
posted by sephira at 9:20 PM on October 8, 2007

I find that I can get her to switch directions most easily if I blink rapidly a few times at just the right rate. That works for me a lot better than staring at her foot does.
posted by hades at 9:20 PM on October 8, 2007

I can only see it clockwise, no matter how much I block out.
posted by Mr. President Dr. Steve Elvis America at 9:22 PM on October 8, 2007

OK, after several minutes of swearing that it could not go counter-clockwise, I finally figured it out.

I covered up everything but the the very bottom of the shadow, where there's just a foot moving from right to left. Then I decided whether I wanted the shadow foot to pass in front of the shadow leg or behind the shadow leg. Then I looked away, and I looked back.

With these steps I can make her rotate in either direction. Then I just uncover her. And it sticks.
posted by yeolcoatl at 9:23 PM on October 8, 2007

NO SWITCHY! Goddamnit!
posted by schwa at 9:26 PM on October 8, 2007

Ah there we go. In a fit of desperation i turned the laptop screen sideways. All of a sudden she was turning in the other direction. But I've been trying for so long i forgot which way she was originally turning.
posted by schwa at 9:28 PM on October 8, 2007

The eyes cannot see what the mind cannot perceive.
posted by Avenger at 9:36 PM on October 8, 2007

She's counterclockwise for me when I look directly at her, but clockwise in peripheral vision. Always.
posted by roll truck roll at 9:40 PM on October 8, 2007

She started out counter-clockwise, then switched to clockwise... and now she KEEPS SWITCHING BACK AND FORTH!!

Witch!!!!!
posted by bigbigdog at 9:41 PM on October 8, 2007

If only we all had the power to get girls to go both ways at will.
posted by empatterson at 9:43 PM on October 8, 2007

Startled me! I knew this was another necker cube phenomenon, but having glanced at it a few times (ccw), I got distracted, and when I glanced back -- it had changed!

I find this one very hard to switch. If I narrow my focus down to one rotating foot, I can force myself to think through what would be happening were it spinning "the other way" and then, looking at the whole image, it is.

Very neat.
on preview, what googly said.
posted by dreamsign at 9:58 PM on October 8, 2007

After ten minutes of feeling highly disempowered (emasculated?), I got it. Just stare at her legs, and DECIDE whether the swinging-around one is going to pass in front or behind the steady inner one. If you visualise it passing in front when you're expecting it to pass behind, you can make her switch.

The visual cues (shadow, light, texture) that we normally use to disambiguate the two aren't there, so we read it in according to our preferences.
posted by bicyclefish at 9:58 PM on October 8, 2007 [1 favorite]

Anyway, looking at the dancer, if I told myself she moved clockwise, she moved clockwise, and if told myself she moved counter-clockwise, she did. The feet thing didn't seem to have any effect, I just had to tell myself she moved in a certain direction and it happened.

That's interesting to me. I'd be curious to know whether beliefs about the direction the dancer should be turning really do influence your interpretation, or if something else is going on.

One of my psychology professors who works in visual imagery claims that because low level vision is cognitively impenetrable (meaning it can't be influenced by high-level beliefs), the gestalt-like switch in pretty much all illusions of ambiguity (such as the Necker cube) is due to where we focus our focal attention. Eye-tracking experiments confirm this. After fixing out attention on certain aspects of the image, our interpretation of the scene is pretty much automatic.

It seems like the dancer's rotation is something that should be computed at a relatively low level in the visual system. What happens in cognition to cause the switch? Is it merely a reassignment of focal attention? Or is something else involved? This is a complex illusion.
posted by painquale at 10:05 PM on October 8, 2007

Jesus. Concentrating on the area around the knee of the outstretched leg, I was able to make it switch once every half a rotation, giving a very strange effect.
posted by dreamsign at 10:06 PM on October 8, 2007

This is bizarre- it seems every time I blink she's changing direction. IT'S WITCHY! BURN IT! BUUUUUUUUURN IT!
posted by maryh at 10:20 PM on October 8, 2007

OK, I'm no-brained enough that it took me 5 minutes to figure out which direction spin constituted clockwise.

Oy.

I can only see her flip to counter-clockwise if I look at her out of the corner of my eye.
posted by jamaro at 10:20 PM on October 8, 2007

I can only see her flip to counter-clockwise if I look at her out of the corner of my eye.

She loves it when you do that.
posted by rokusan at 10:36 PM on October 8, 2007

I noticed the same as googly, except default's clockwise.
when the foot touches shadow, looking up from that point can switch her direction.

the fact that they know how to invoke this illusion unnerves me.
posted by Busithoth at 10:50 PM on October 8, 2007

Oddly, I can hit refresh and it will reliably rotate clockwise for a moment, stutter, and then reliably rotate counter-clockwise for an indefinite period of time. I can hit refresh before she appears to switch direction, and have this pattern occur; or I can hit refresh after her apparent switcharoo, and have this pattern occur.

I can not rule out the possibility that the frame order is reversed at random. It strikes me as quite odd that the first few seconds of a refresh have a consistent pattern.
posted by five fresh fish at 10:53 PM on October 8, 2007

...otoh, a few more minutes of staring and I can make her ping-pong pretty much at will. Very cool illusion!
posted by five fresh fish at 10:55 PM on October 8, 2007

I need to see this live to be sure this isn't an illusion. Anyone have the model's number?
posted by maxwelton at 10:56 PM on October 8, 2007

there's no image trickery here. i couldn't get anything to happen by focusing on the feet, but the thing that worked for me was to look away from the screen, so that i was seeing the image with my peripheral vision. by looking away just the right amount, so that i could just sort of start to make out details, i found that i could interpret the image as rotating one way or the other. then when i looked back, it was rotating whichever way my peripheral-vision brain had been last set for.

what's more interesting to me than the right/left brained-ness of this is the distinction between those who can easily switch between interpretations, and those who are stuck with one or the other. i bet it says something about what part of the brain the image processing is happening in, but i'm not really sure what. fascinating to think about though.
posted by sergeant sandwich at 11:08 PM on October 8, 2007

I stared at it for two minutes... ...and now I have a strange compulsion to refinance my mortgage. Spooky.
posted by blenderfish at 11:12 PM on October 8, 2007 [1 favorite]

I can get her to bounce back and forth, always facing me.

Follow the tips of her toes of the raised foot - when it reaches the far edge (left or right) move your gaze to her body. (or just stare at the toes). Repeat.

Maybe they have some reason to say this is a left/right type of thing, but I suspect it's actually more dependent on what side of the frame her raised foot is on when your brain makes the determination.

If that doesn't work, here's a cheat:

1. get a hand mirror
2. watch the reflection of the figure spin until the raised leg reaches the left or right side of the frame
3. take a bong hit
4. unplug the internet so the government can't monitor what you're doing
5. lose the pants
6. crap, is that the pizza guy at the door or the cops?

where was I?
posted by Davenhill at 11:15 PM on October 8, 2007 [1 favorite]

I'd hit it
posted by Catfry at 11:18 PM on October 8, 2007

Nuuuuts.

I was totally clockwise for the longest time till I started focusing on the hand that is near her body. Then she switched to counter, and for a while it seemed like I could get her to go back and forth just by mentally remembering how the other way looked. Then I got stuck on counterclockwise.
posted by Phire at 11:28 PM on October 8, 2007

Wow, that is so bizarre. The image defaults to counter clockwise for me (which seems doubly bizarre reading the left/right brain info) but I can now get her to change fairly easily by focusing on the foot.

So weird!
posted by aclevername at 11:33 PM on October 8, 2007

Clockwise, no matter how I look at it. Trying some of the suggestions above made no difference.

Hmph.
posted by aerotive at 11:42 PM on October 8, 2007 [1 favorite]

From a recent new scientist article (subscriber protected, so I pasted it all here)...
http://www.newscientist.com/channel/being-human/mg19526221.300-mind-tricks-six-ways-to-explore-your-brain.html

3 A brain of two halves

WOULD you consider yourself to be logical and analytical or creative and empathic? According to popular psychology you're one or the other, and it's all down to which half of your brain you use the most: the rational and calculating left or the intuitive, artistic right.

It's a myth, of course, but like all good ones it contains a grain of truth. Your cerebral cortex - the outer layer of your brain that deals with higher functions - is indeed split into two halves. They are connected by a flat bundle of nerve fibres called the corpus callosum, but work in subtly different ways - and these differences occasionally flicker into your conscious awareness.

The left-brain/right-brain myth arose from experiments done in the early 1970s on people who had had their corpus callosum cut as a last-ditch treatment for epilepsy. These "split-brain" patients showed some strikingly odd responses to information that was preferentially sent to one side of the brain or the other by presenting it to the extreme left or right of their visual field. This works because the right visual field is monitored by the right eye, which routes straight into the left brain, and vice versa.

For example, when a word or picture is presented to their right brain, split-brain patients are often unable to read or recognise it. This and similar experiments led to the idea that the left side of the brain deals with logic and facts while the right side is more intuitive and interpretive. We now know that this dichotomy is too simplistic, but its essence holds true. The latest view is that the two hemispheres have subtly different styles of information processing: the left has a bias towards detail, the right a more holistic outlook. You can watch a video of a split-brain experiment at www.youtube.com/watch?v=ZMLzP1VCANo&mode=related&search=.

Most people, of course, have a functional corpus callosum that shunts information between the hemispheres. Even so, subtle left-right differences exist. One task where the hemispheres operate differently is face recognition. When most of us see a face, our right cerebral hemisphere does the lion's share of the work recognising its gender and decoding its expression. And because the right hemisphere is fed by the left visual field, that means we have a notable left-sided bias in our judgement of faces.

Look at this pair of faces (left). Which appears happier? Chances are you chose the bottom one. The two faces are, however, identical apart from being mirror images of one another. The picture is called a chimeric face and is made by taking two pictures of the same face, one with a neutral expression and the other smiling, chopping the pictures in half and joining the two mismatched pieces. Our general bias towards the left side of the face (as we look at it) makes us see the faces as different even though they are essentially equivalent.

It isn't just visual processing that is lateralised. There is some evidence that emotion is too, with the right side of the brain more specialised for negative emotions and the left for positive ones. Amazingly, simply activating one or other hemisphere by moving parts of your body can noticeably change your emotional state.

You can experience this by repeating an experiment first done in 1989 by Bernard Schiff and Mary Lamon of the University of Toronto in Canada (Neuropsychologia, vol 27, p 923). They asked 12 volunteers to perform a "half smile", lifting one corner of their mouths and holding it for a minute. Left-smilers reported feeling sadder afterwards, while right-smilers felt more positive.

Other researchers have reproduced the effect simply by getting people to contract the muscles of their left or right hand a few times. More recent research has suggested that motivation is similarly affected: people who performed right-sided muscle contractions became more assertive and spent longer trying to crack an impossible maths puzzle.

Unsurprisingly, these claims are controversial, with some teams failing to replicate the results. Last year, however, Eddie Harmon-Jones of Texas A&M University in College Station used EEG to confirm that flexing the hand muscles produces changes in emotion, but only when it is preceded by activation of the opposite cortex (Psychophysiology, vol 43, p 598). The left-brain/right-brain legend, it appears, is alive and well.
posted by leibniz at 12:57 AM on October 9, 2007 [4 favorites]

I've always thought of this illusion as a variant on the Ames Window. The Exploratorium link that alexei provides has a good explanation:

TRAPEZOIDAL WINDOW takes a familiar-looking object to illustrate how strongly experience influences what we see. What looks like a window swinging back and forth is really a rotating trapezoid. When the viewer stands far way or looks with one eye, the eye-brain ignores the perspective clues about the true shape of the object in favor of what it is used to seeing

You can see a kind of crappy demo of the Ames Window here, and here.

I'm not sure why the article talks about left brain/right brain differences -- as far as I know, this perceptual illusion has absolutely nothing to do with lateralization of brain functions.
posted by tickingclock at 1:06 AM on October 9, 2007

This made my brain hurt for a minute. At first, I could not imagine it spinning any way other than clockwise. Then I stared at the foot, it reversed, and I couldn't get it back. Just now I think I found the "cheat" for making it switch at will: blink quickly to "strobe" the scene while imagining the reversal. Somehow, it made it infinitely easier. I just did it twice, seems to work.
posted by Edgewise at 1:34 AM on October 9, 2007

Why do our brains hurt? (Mine does too). Are we creating new pathways and reducing the likelihood of alziemers? Perhaps it is just eye strain. (But I'm sure it's my brain that hurts - am I damaging it? What's happening in there?)
posted by b33j at 3:58 AM on October 9, 2007

So is there a genuine predominance of people who see the rotation as clockwise? Or did item's comment set people up to see it that way?

For me it was solidly counterclockwise, and it took a couple of minutes of concentration for me to switch it round. Closing my eyes and then opening them whilst mentally picturing the rotation in the chosen direction seemed to do the trick.
posted by le morte de bea arthur at 4:29 AM on October 9, 2007

I don't see how this is even a question. Clearly clockwise and I can't make it switch any more than I can see her face (as much as I'd like to--nice nips.)
posted by DU at 4:30 AM on October 9, 2007

Oh fuck no.

I wasted hours on this when I saw it a few months back. I covered, I tilted, I deconstructed the image, I'm not going there again.

Ralph's viking is a metaphor; .999r is 1, but only because repeaters are placeholders for fractions; a plane can't take off from a conveyor belt, and if you think this shadow bitch turns in more than one direction, you've got another thing coming.

Fuck y'all.
posted by Uther Bentrazor at 5:11 AM on October 9, 2007 [2 favorites]

If I concentrate out her outstretched foot, I can fool myself into seeing it as her just rocking from side to side - not turning at all!

Sweet.
posted by 6am at 5:16 AM on October 9, 2007

I have seen many messages after his/hers, but many metafites haven't realised that yeolcoatl Has it:

I covered up everything but the the very bottom of the shadow, where there's just a foot moving from right to left. Then I decided whether I wanted the shadow foot to pass in front of the shadow leg or behind the shadow leg. Then I looked away, and I looked back.

With these instructions I can see the girl rotate clockwise or counterclockwise at will, with almost no lag in response: I just llook at the foot shadow, decide whether it's passing in front or behind the leg shadow, and it happens.

It's like Dawn in season 5 of Buffy in that the girl doesn't seem to reverse direction, it's almost as if *she had always been turning in the new direction*! Spooky!
posted by kandinski at 5:17 AM on October 9, 2007

Clockwise all the time, can't make it flip at all. I wonder if it's something to do with ghosting on my monitor producing an illusion of shading? I'm going to try it on some different screens and see if I can get a different result.

(And I know I should ignore it, but that "sciencey" left/right characteristic listing is deeply irritating. Grr.)
posted by tomsk at 5:38 AM on October 9, 2007

If you're still having trouble try this: say "front" and "back" for a few times when you see those sides facing you. Then say it in reverse. I think it helps when you stare at the hips when you make the transition.

Also try thinking that she isn't spinning at all, just swaying from side to side while facing you the whole time. When the raised foot reaches its farthest left or right, she changes direction and sways back the other way.

Now that Ames Window really hurts my brain.
posted by effwerd at 5:44 AM on October 9, 2007

That's cool. I can't figure out what that should affect the head tilt, though. Maybe we're switching the orientation of the torso as well, i.e. towards/away from us.
posted by carter at 5:49 AM on October 9, 2007

One freaky thing I noticed is that when you reverse direction, you reverse the side of her body that she is holding the leg up. I don't want to look anymore, brain pain.
posted by Edgewise at 6:01 AM on October 9, 2007

I stared for half an hour and she started impersonating a digital clock.
posted by Crusty at 6:11 AM on October 9, 2007

I tend to see the dancer moving clockwise, but I also found that with a little concentration I could make the image switch to counter-clockwise rotation. I'm very skeptical about what this reveals about right-brain vs. left-brain thinking. Is that indicative of a right-brain dominant, yet switch-hitting thinker? OK, now I HAVE to get back to work!
posted by Dead Man at 6:29 AM on October 9, 2007

It's a sailboat.
posted by Who_Am_I at 6:42 AM on October 9, 2007

I find it helpful to stare at her nipples. Does that mean I think with my 'south brain'?
posted by LordSludge at 6:43 AM on October 9, 2007

It's an interesting exercise....getting your brain to see it either way at will. That one could apply such a skill to all problems.
posted by zorro astor at 6:55 AM on October 9, 2007

What blows my mind more than the illusion is that there are people here who flat out refuse to believe that she can be perceived as spinning either way. Is that just sarcasm? Bitterness? Surely you can't honestly believe that she's only capable of spinning in one direction.
posted by solipsophistocracy at 7:32 AM on October 9, 2007

Well done illusion. I bet it could be applied to any spinning object. The trick being that it's a perfectly symetrical silhouette and each body part passes through the center of the axis and emerges into the identical shape.

I found it very difficult to change the direction while looking at the whole image and it seemed to occur when I'd given up trying to will it in an opposite direction.

Then, I used my hands to crop out everything except her calf (the one she spins on) and could easily choose which way she would spin when I removed my hands.
posted by JBennett at 8:17 AM on October 9, 2007

I've been practicing, and I can now switch at will by keeping the stripper, uh, I mean, dancer, in my peripheral vision (and blurring it slightly) and concentrating on her raised leg as it crosses the axis of her body--is it in front going behind or vice versa? That's when I make the switch. I'm going to go vomit now.
posted by SixteenTons at 8:50 AM on October 9, 2007

She's obviously a submissive, but I can make her switch to a dom in my imagination after the first forty strokes or so. However, if I'm wearing my testicle weights and nipple clamps, I can get that speed down to about twenty strokes
posted by PeterMcDermott at 8:57 AM on October 9, 2007

This is a viral ad for the Democrats, isn't it?
posted by cenoxo at 8:58 AM on October 9, 2007

I can get it to switch, but it is predominantly clockwise for me.

The responses here remind me of the "Magic Eye" craze in the 90's.

IT'S JUST STATIC! IT'S A TRICK AND THERE'S NO REAL PICTURE HERE. I HATE YOU.
posted by exlotuseater at 9:28 AM on October 9, 2007

There is no spoon.
posted by The Bellman at 9:35 AM on October 9, 2007

OMGWTF?! She was obviously going clockwise, just spinning along, a little repetitive, what's the big deal and then WHAM! She switched!

That really is cool. Thanks!
posted by misha at 10:01 AM on October 9, 2007

If you're having trouble seeing both, it might help to just use one eye, and then switch eyes (assuming that the eye you're using is initially correlated to the appropriate hemisphere).
posted by solipsophistocracy at 10:38 AM on October 9, 2007

So, is she standing on the face of clock or is she beneath the face of a clock - I mean, which way is clockwise? Is your clockwise the same as mine? do you see blue when I point at things that are red?
posted by mouthnoize at 10:49 AM on October 9, 2007

I'm just really impressed that she doesn't get dizzy.
posted by quin at 10:57 AM on October 9, 2007

Someone needs to dummy up a version of this that blasts you with the Exorcist girl's face and a loud scream after about 45 seconds.
posted by hermitosis at 11:06 AM on October 9, 2007

God I hate you all. No matter what tricks I try and how long I stare at her, I CAN'T GET HER TO SWITCH FROM CLOCKWISE!!!!!

exlotuseater: The responses here remind me of the "Magic Eye" craze in the 90's.

Oh I can't do that either. Found out after some googling and wiki-ing that it was probably due to amblyopia... so I blame that here too! DAMNIT!!!
posted by ClarissaWAM at 12:28 PM on October 9, 2007 [1 favorite]

I don't get it. Spinning? All I get is a two dimentional picture that changes shape.
posted by Pollomacho at 12:32 PM on October 9, 2007 [1 favorite]

Big page of illusions, including this one and a similar spinning ferris wheel one. That author attributes the first appearance of the spinning dancer here, but that author claims it's even older.
posted by yhbc at 12:36 PM on October 9, 2007

you know i could never get the magic eye things to work either, so maybe i have amblyopia or whatever.
posted by jcruelty at 12:46 PM on October 9, 2007

Place your hand at one side of the image so you can see it peripherally. Raise your hand slightly and point your index finger down and slightly toward you, then spin your finger around counter-clockwise. Make sure you are looking at the spin from underneath. This predisposes your brain to see an anti-clockwise spin from below. When you notice her spinning the same direction, you can look directly at the image and it will hold in that direction.

To get her spinning the other way, lower your hand slightly, poing your index finger up and slightly toward you, then spin your finger around clockwise. Make sure you are looking at the spinning finger from above.
posted by Araucaria at 1:03 PM on October 9, 2007

s/poing/point/
posted by Araucaria at 1:03 PM on October 9, 2007

I think it's a powerful political metaphor. Those who see it spinning to the left are Lefties. Those who see it spinning to the right are Righties. Both swear that their way of seeing things is the only possible way, and will viciously attack any who would question their view. And those of us who understand that it can be seen two ways "depending on how you look at it" ...well, I'll see the rest of you in the gulag or the secret detention center, I guess. Or perhaps in a vase-shaped prison with two faces staring at us...
posted by haricotvert at 1:34 PM on October 9, 2007 [1 favorite]

What blows my mind more than the illusion is that there are people here who flat out refuse to believe that she can be perceived as spinning either way. Is that just sarcasm? Bitterness? Surely you can't honestly believe that she's only capable of spinning in one direction.

I really want to be able to see her counter-clockwise. I feel pretty limited. I've tried all of the suggestions in this thread. But she's going clockwise. And I insist on this the same way I could insist that a real dancer is spinning clockwise or not.

Look, I just got up and twirled a few times, clockwise. Anyone who'd say I was going counterclockwise would just be wrong. I don't see the difference. The figure is going clockwise. I just spun around in my chair...clockwise. Now I just spun counter-clockwise. Clearly different.

I can't see her other than as she is. It's not an illusion to me. It's a shadow figure spinning clockwise. Once again, I fail.
posted by Danila at 3:31 PM on October 9, 2007

I'd guess the optical trick is that the direction she appears to be spinning is dependent on whether your brain thinks her outstretched leg is on the near side of her body

That's how you switch them. First say...this time the raised foot is going in front of the leg. Let that happen for a while. Then say...now the raised foot is going behind the leg. It should switch. Good luck.
posted by telstar at 4:44 PM on October 9, 2007

I understood how it could look either way long before I was able to see it both ways.

I think it really helped me to stare at the Ames window silhouette animation tickingclock linked for a little while and then looking back at the spinning girl. Both are completely black, two dimensional images changing shape that could look like they are spinning around or flapping back and forth.

It's not like you spinning around, because she's not real and she's not really spinning.
posted by lampoil at 5:04 PM on October 9, 2007

It isn't amblyopia. Because that limits me and the magic eye too (and geez do I have the eye surgery and prescription to prove it), but I can make the dancer switch at will.
posted by dame at 6:56 PM on October 9, 2007

GOD this is maddening, i've gotten to where if i just look at the foot i can see it going counterclockwise, but as soon as i look at more of it it pops back to clockwise. driving me nuts.
posted by jcruelty at 7:54 PM on October 9, 2007

Squinting is very effective. Squint so much that you can barely see movement, and try to relax. Squint through one eye with the other eye closed. Switch eyes if it's not working. Eventually it'll flip, if you just relax and stop trying to will it.

For those convinced it doesn't flip -- you're wrong, but the idea of a big con kind of reminds me of a college drinking game called "Jet". The name of the game is Jet. Jet calls three! Anyone know it?
posted by haricotvert at 8:59 PM on October 9, 2007

rip the gif and get over your imaginative, big picture powers. 1:50 frames one way, 1:50 another. sigh...taze me bro.
posted by wallstreet1929 at 9:32 PM on October 9, 2007

That certainly explains the reload glitch and, really, it was the only realistic answer to that glitch. What's weird is the time distortion: I could swear it sometimes ping-ponged; other times seemed to take forever.

Perhaps that's a subtle effect of having a multitasking system: as the load varies, the frame timing varies ever so slightly, and one's mind distorts it.

Or maybe it's just we're the shits at judging that sort of thing. Brain numbs out or some such thing.

Whatever it is, it was cool.
posted by five fresh fish at 9:48 PM on October 9, 2007

got it! finally!

that is really the most astounding illusion ever.
posted by jcruelty at 11:12 PM on October 9, 2007

Clockwise for me.

"RIGHT BRAIN FUNCTIONS
uses feeling, "big picture" oriented, imagination rules, symbols and images, present and future, philosophy & religion, can "get it" (i.e. meaning), believes, appreciates, spatial perception, knows object function, fantasy based, presents possibilities, impetuous, risk taking"

Hmm. That's probably why I can't stand corporate-life. Not one person "gets it".

Stupid counterclockwise weenies.
posted by dasheekeejones at 4:07 AM on October 10, 2007

I tried yesterday. I tried today. Clockwise only. My brain hurts.

Showed the link to my partner, for whom it was immediately counter-clockwise, and then she exclaimed, "She switched!"

Clearly the left side of my brain is rotted away.
posted by atayah at 7:29 AM on October 10, 2007

She spins clockwise if I emphasize with her -- seeing it from her perspective -- looking down on her feet. But if I imagine myself staring up on her from beneath that transparent floor while hidden in the shadows, drooling and touching myself, she spins counterclockwise -- implying a masculine type of brain. Yes, this test really works! It’s not much of a visual illusion though.
posted by JeNeSaisQuoi at 8:12 AM on October 20, 2007

It's hokey pop-psych, but doing maths in my head could make her switch directions if I focused on them for long enough, and then humming a tune made her return to spinning clockwise. It shouldn't work, but, dammit, it does.
posted by kyleg at 10:55 PM on October 20, 2007