I know it’s not actually 3-D but the figure itself looks like something one might create with the 3-D modeling program called Poser… I actually wouldn’t be surprised if it was created with that.

Anti-clockwise, Sadie?  Don’t you mean widdershins?

Dof- I’m suspicious of astrology too.  But that’s typical for us Aries…

The left-brain right-brain dichotomy is real, but most of the pop-psychological interpretation riding on it is, well, astrology.  That goes, I strongly suspect, for this dancer too.

Since our retinas are 2-D, our vision is also 2-D: not just internet pics but everything we see is “flat”.  Of course, we can reconstruct the third dimension in various ways: accommodation, stereoscopy, shading, perspective, etc., but the images we get are still flat.

Les how did you get the picture to animate, you know, how did you get the girl to twirl like that, and please don’t tell me “practice!“

It rotates for you all too?
I thought it ‘twere the pills

I tried just “save picture” but the bitch won’t twirl.

Save as .gif and open in “windows picture and fax viewer” or similar. MS Paint can’t handle animation (if that’s what your default is)

Moses, I didn’t create this animation. It’s a standard animated GIF file so as long as you have a picture viewer that will work with it, see Bahamat’s suggestion, it should spin as soon as you open it.

Quicktime will twirl her too.

It seems to me to be of the same illusion type as the Necker Cube or the widow/bride illusion

The spinning illusion in perfect silhouette is due to the fact that features do not change angular size as they rote to near and far perimeter of the circle.  If it were a real physical object spinning in front of a camera with a wide-angle lens (telephoto would more approximate the flattening effect) there would be no ambiguity about which direction it was rotating.