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The Spinning Woman
This optical illusion is so compelling it is hard to believe that it is an illusion and not a computer trick. I have my doubts about the left-brain right-brain story but check it out. Which way does she spin and does this fit your profession?
Posted by Alex Tabarrok on October 13, 2007 at 07:10 AM in Science | Permalink
Comments
Repeatedly opening and closing my eyes, or looking away and back again, I sometimes see clockwise rotation and sometimes counter-clockwise rotation. My background is in the hard sciences.
Posted by: David Wright at Oct 13, 2007 7:29:20 AM
I had it clockwise, then read the text, and when I looked back to the picture, it was counter-clockwise. After enough staring I was able to get my brain to see it as clockwise again.
I'm pretty sure it is neither an illusion nor a computer trick. I work with 3D models all the time, and if you look at a 3D wireframe without any perspective added, it is impossible to tell what is the front and what is the back. By rendering in all black without any shading, they get the same effect -- the picture would look exactly the same whichever way it was rotated. So the perception of direction comes from whichever interpretation of the picture your brain clings to.
Posted by: Sol at Oct 13, 2007 7:40:18 AM
I have my doubts about the left-brain/right-brain story, as the first time I saw it, she was spinning clockwise, and it was very hard to see it the other direction, but I'm definitely a left-brain sort. Maybe the rotation pattern is reversed for Australians?
Posted by: Anthony at Oct 13, 2007 7:45:09 AM
OMG!! this is so awesome. I first saw it turning anti-clockwise, then after reading the test I saw clockwise, and then by focusing hard and long enough I could make it turn clockwise and anticlockwise at will!!! this is so amazing!!
Posted by: rahul at Oct 13, 2007 7:57:23 AM
I see it clockwise and can't get it to change. And I'm about as left-brained as you can get! A computer programmer by trade, with no artistic talents and frequently confused by spatial relationships.
Posted by: Michael at Oct 13, 2007 8:05:26 AM
I think it is fake. I looked for a while and thought that I saw her switching to the other direction - twice! Oh well, I may be naive about 3D.
Posted by: J at Oct 13, 2007 8:25:22 AM
I see it clockwise and I can't get it to change. I'm a computer programmer with artistic talent.
Posted by: Thomas at Oct 13, 2007 8:37:17 AM
This is so cool. It's counter-clockwise for me - but i could get it to switch by shifting my focus to other parts of the screen for a few seconds. My background is in engineering.
Posted by: Nitin at Oct 13, 2007 8:39:38 AM
I can't get any effect except clockwise. I wonder if it's because my two eyes aren't exactly the same -- one is better for close, one is better for distance. The right-brain/left-brain theories are often over-interpreted (to say the least). Maybe there are better explanations.
Posted by: anon at Oct 13, 2007 8:41:40 AM
When I first looked, it was counter-clockwise. Then, after staring at it for a couple of minutes trying to get it to change direction, it was still counter-clockwise and I was dizzy. Economics graduate student.
Also, based on proportions, is this a rotating pornstar?
Posted by: David Jinkins at Oct 13, 2007 8:43:51 AM
When I first looked, it was counter-clockwise. Then, after staring at it for a couple of minutes trying to get it to change direction, it was still counter-clockwise and I was dizzy. Economics graduate student.
Also, based on proportions, is this a rotating pornstar?
Posted by: David Jinkins at Oct 13, 2007 8:44:06 AM
I see it clockwise and can't get it to change. And I'm about as left-brained as you can get! A computer programmer by trade, with no artistic talents and frequently confused by spatial relationships.
Oh no, somebody else already SAID THAT! But it goes double.
Posted by: Jens Fiederer at Oct 13, 2007 8:47:58 AM
It´s a trick. You only have to wait 30 sec. and you´ll see her change the spinning way.
Posted by: at Oct 13, 2007 8:55:24 AM
This is an animated GIF picture. It is comprised of 34 individual frames, each showing the "girl" from a slightly rotated perspective, like a "flip-book". If you scroll through each frame manually, you can see the rotation.
The "trick" part is that the way she is drawn can and does lead the mind to interpret the movement as BOTH clockwise and counter-clockwise movement. It's not a computer "trick."
Though I do think the "left-brain", "right-brain" accompanying text is just plain BS....
vty,
--Dennis
Posted by: Dennis Liu at Oct 13, 2007 9:02:30 AM
This is an example of what we who study perception call a bistable percept. That is, it's a stimulus that has two stable interpretations that someone exposed to it will flip between, given a long enough period of time. This is really just an advanced version of the Necker Cube (findable through a brief search). It's interesting in that sense, but it has very few implications for neural processing.
The right/left brain story is utterly ridiculous. While there is some differentiation between the right and left hemispheres of the brain, it has absolutely nothing to do with how "logical" one is, or "creative." If you needed any proof beyond the say so of someone who works on brain stuff, consider people who've undergone hemispherectomies, i.e. people who have had an entire hemisphere of their brain removed. This is sometimes done in childhood for intractable epilepsy. If done early enough, these people end up being developmentally normal. One of them a few years ago completed a degree at the University of Cambridge. No major functions can be entirely localized to a hemisphere in light of evidence like this.
Also, which hemisphere is more active in a given task seems to be correlated mostly with handedness. Are all lefties holistic artists?
Posted by: J. Riley at Oct 13, 2007 9:16:39 AM
No wonder I don't like mathematical economics :)
Posted by: David Zetland at Oct 13, 2007 9:21:24 AM
It was initially counterclockwise but I can now make it shift back and forth about every 10 seconds. I focus on the foot that is on the ground and the spinning leg to get it to shift.
Posted by: AZ at Oct 13, 2007 9:25:36 AM
Awesome, just an update on my last entry, i am now able to turn the girl within 15 seconds by changing my perception, and I am a budding economist! does this justify claims that economists switch sides as fast as their mind works?
Posted by: rahul at Oct 13, 2007 9:47:11 AM
Very interesting - initially I saw it as CCW, I am a PhD student in the hard sciences.
I second Sol's opinion - the illusion is real. When going CCW, the perspective on the dancer is at a slight upward angle, so the ellipse the hand traces is higher when the hand is closer to you, and lower when away. When going CW, the opposite is true - the perspective on the dancer is at a slight downward angle, so the hand is higher when away from you, and lower when closer to you. This allows the same animation to go both CW and CCW. All other body parts trace similar ellipses.
To switch direction, focus on one body part (foot, for example), and mentally switch perspectives from higher to lower or vice versa.
Posted by: altoids at Oct 13, 2007 9:49:20 AM
At first, I thought it was a computer trick. I was absolutely sure that when I sasw here turning counterclockwise, her face went from facing right to facing *backwards*, and the ponytail went from facing left to facing me. So when she switched, I thought it must be a scam.
Then I figured out how to make her switch on demand. I was also able to see her facing me full-time and going back and forth. Very impressive illusion.
I'm a software developer, and my first view was counterclockwise.
Posted by: Phil at Oct 13, 2007 10:15:29 AM
Clockwise, although by hiding the legs I could see it turning the other way. Diplomat
Posted by: Tom at Oct 13, 2007 10:17:24 AM
Me: engineering; first saw it CCW, now it changes at random but usually CCW.
And did they REALLY have to include the nipples to get the illusion to work?
Posted by: Person at Oct 13, 2007 10:22:46 AM
My wife and I saw opposite directions at the same moment, so not a trick, I suppose. I saw it mostly clockwise, but some the other way.
Posted by: Daniel Klein at Oct 13, 2007 10:49:49 AM
Clockwise. Could not get to counter-clockwise at all. The theory does not fit with my backgound at all.
Posted by: Bernard Yomtov at Oct 13, 2007 10:59:40 AM
Programmer, clockwise. Can occasionally switch it.
Posted by: Braden at Oct 13, 2007 11:15:54 AM
