*promote... this is seriously cool, and much easier than the damn ballerina.

>> ^coolhund:
"According to Dr. Rankin, if you didn't get the sarcastic tone of the previous sentences you must have some damage to your parahippocampal gyrus which is located in the right brain. People with dementia, or head injuries in that area, often lose the ability to pick up on sarcasm, and so they don't respond in a socially appropriate ways."

Either that or they haven't found Jesus.

lol he got 2 minus. Proves that there are still people out there who dont understand sarcasm.

"According to Dr. Rankin, if you didn't get the sarcastic tone of the previous sentences you must have some damage to your parahippocampal gyrus which is located in the right brain. People with dementia, or head injuries in that area, often lose the ability to pick up on sarcasm, and so they don't respond in a socially appropriate ways."
http://news.yahoo.com/s/livescience/20080620/sc_livescience/sarcasmseenasevolutionarysurvivalskill

>> ^E_Nygma:
i'll be honest, when i clicked on the link at first, i was wondering what language it was.

i'll be equally honest: i knew what it was, without a moment's doubt.
but this had me completely fooled, the first time.

it's one of those left-brained, right-brained things.

are you kidding me? blankfist is responsible for driving me INSANE for 3 days trying to get that damn ballerina to work all proper like! ...then again, i guess he made up for it by giving me a one-word catchphrase to irritate all my friends with. congrats!

Cool illusion, but yeah, the left-brain/right-brain thing is BS. Whether you see it going clockwise or counter-clockwise has nothing to do with your brain function, intelligence, inclinations, talents, or whatever. It's just visual perception.

how did you do it. this is driving my crazy

Q

In reply to this comment by gorillaman:
OMG she's going anti-clockwise. Finally.

from my brother-in-law, who does research in cognitive psychology:

As far as I can tell, it's an optical illusion that is in the same class as the necker cube, an illusion that I'm sure you are all familiar with, even if you don't know it by name. Both of these are "bi-stable images" (or, in the case of the ballerina, a bi-stable movie, I guess), that your brain can interpret in one of two ways. If you are looking at the cube, with a little practice, you can force it to switch between the two interpretations pretty easily. I suspect that a forced switch will be harder with the ballerina because it's a moving image, but it should be possible. I've found that if I focus just on her planted foot, I can get the rotation to change directions almost at will.

How does it work? The key is that what you are looking at is essentially a two-dimensional image (I was going to say it was a flat image, but that's clearly not the case...) of the ballerina. There are no depth cues and no 3D shading. It is as if you are looking at the projected shadow of a twirling ballerina, if that makes sense. With that in mind, think about it this way: Imagine the ballerina is facing exactly sideways (right or left, doesn't matter). Then imagine that she spins, say, 45 degrees. First, think about what she would look like if she was spinning toward you. Then think about what she would look like if she was spinning away from you. Remember that all you have to look at is a shadow - you can't see a face or any other front/back distinctions. What you should realize is that if she spins 45 degrees "away" or 45 degrees "towards" you, the resulting image is exactly the same. Spin her another 45 degrees (so she's now rotated 90 degrees), and she will either be facing you or she will have her back to you, but again, since it's just a shadow, the image is exactly the same... What it boils down to is that with a 2D projected image (of a ballerina, of a motorcycle, anything, really, there's nothing special about the image they chose), you do not have enough information to tell the direction of rotation. They add the shadow of the feet to make the image more interesting, but again, there's no real rotational information there.

Since you don't have enough information, your mind could choose between two equally likely interpretations (hence the "bi-stable image" name). So when you look at it, your brain picks one interpretation, and then typically sticks with it until it is pushed to reinterpret the image (either by looking away for a while, or really trying to convince yourself that the image is going the other way or, I don't know, whatever else works).

As far as the right-brain, left-brain stuff goes, I don't put any real scientific faith in that terminology. Yes, certain functions like language skills and spatial processing are more localized to one side of the brain than the other. However, calling someone "left brained" or "right brained" should be viewed as an easy label to use to indicate if someone is more creative or more analytical, but it's more like saying that they are "introverted" or "extroverted" than it is a statement about their neuroanatomy.

Does the spin direction of the image reveal your brain-sidedness? I highly doubt it. I can't think of any reason that such a test would be diagnostic.

-- He's way smart.

I seem to have two right brain halves... Drives me nuts!

Next thing I will see spinning is my laptop out the window in a second (clockwise)

For "Discuss!": http://www.videosift.com/video/The-Right-Brain-vs-The-Left-Brain

The whole left/right brain thing is nonsense. There is such a thing as hemispheric dominance, but it doesn't have any bearing on your personality. And this animation isn't even a test for it. I wish people would leave this silly little myth behind, it's so brainless for people to keep spouting "oh yes, I'm a left-brain person" as if it means they're all artistic and woo. It's embarrassing.

It spins both ways for me too.

Oh, and the left-brain/right-brain non-sense has been shown to be a bunch of new-age garbage. It means nothing. Some of the greatest artists in history were left-handed. Some of the greatest artists in history were right handed.

It doesn't matter. This is an optical illusion. Look at the feet and you can get her to spin either way. Doesn't mean anything.

Same for me Gorillaman. Even using SG's link, i have no luck. Tried covering up all bar the foot, and just making the foot turn anti clockwise. nope. Not evne with just one eye.

Maybe i have 2 right brains.

let's put this on a job interview test, so that we only hire right-brained people. Seriously, we need to measure every inch of your brain so we can place you accurately.

Well, Eratosthenes calculated the circumference, which is more than just guessing its shape.

But still,information flow hasnt always been like it is now, to put it mildly. One reason I dig this story so much (apart from Sagan telling it) is that this little piece of information, a mere curiousity, could do so much if the right brain happens to come across it, this is why I love the internet so much, it really has potential to change the world, simply over the information flow, its so easy to get information nowadays..

Anyway, for the greater part of the last 3000 years, and certainly all the time before it, information flow sucked. Yes, people back this and this time figured it out, but its not like putting it on Youtube and everyone can cry OLD! three days later. No, most information just got stowed away and forgotten by everyone for hundreds of years before re-emerging, and wars were not being broadcast live on CNN either, news took weeks and months to reach more distant places, and the information had suffered through a heavy game of "telephone" before reaching the majority's ears.

This lack of effective communication prevented people from hearing about disease outbreaks, it created ignorant religions and left most people clueless. Hence you get times like the dark ages, where people thought the earth was flat, hundreds of years after these discoveries. It is readily apparent from an honest interpretation of the Qu'ran, for instance, that Muhammed thought the earth was flat as a pancake.