It is a cool optical illusion but the right brain/left brain stuff is just BS that has been added on by somebody as it moved through the internets. This is about the third time I've seen that make the rounds but the first two times it was just presented as a cool optical illusion without any mention of brain dominance.
Here's a Yale neurologist talking about it. Neat, though; I go through periods where I can switch her at will (there are tricks to it but I usually forget them between viewings) to being perpetually stuck in one direction no matter how hard I try to switch it.