Which Way is She Whirling?

My sister Alex sent this image to me. It was accompanied by a discussion of right brain and left brain. I don't remember which was which.

The image is whirling. Either clockwise or counterclockwise. Click on the image to see her whirl. For some reason, she only whirls off-page.

The question is does she sometimes go the other way? Can you make her go the other way? And, if you can, or if sometimes it happens, how does it happen? What is in the mind's eye that makes it change direction? Can you make it change direction at will?

Where is the thing seen? On the screen or in the mind?