I had to search and search to find this webpage.
My husband and I played with this for quite some time, out of pure wonderment. I thought of it when I mentioned what my brain means to me on another thread, and thought you all might be interested, too.

http://itknowledgeexchange.techtarget.co...e-of-the-brain/

Even if you answer with an A or a B, initially, move your eyes away from the illustration and move them back. I found that if I moved them down to the verbage and read, "What? You don’t believe she could be spinning the other way? Show this to someone who thinks very differently than you do. Or better yet, get a couple of people to look at it at the same time." to look up again afterwards, the direction changed for a short period. My husband could see the image going counter clockwise simultaneously while I saw it going clockwise.... intermittently changing to vice versa. SOOOOO interesting!!!!!! The brain is amazing, simply amazing!!!!

Also, here is a link to trial runs on brain exercises/training, which we can all benefit from: http://www.lumosity.com/.

If anyone has brain exercises they can share, please do.... let's keep them alive and well. I hope sharing these links is ok in the forums... I have no connection to them.