When I don't try to do anything and go into non-doing as in meditation, the image just takes turns spinning left and right, about every 8 - 12 revolutions. After a while of that, this one person spins in both directions simultaneously. Maybe only Buddhists can see such a paradox - or people who have been married for a long time and raised many kids. At that point all awareness of her being female vanishes as well, which I found very interesting. Either I am really smart, or Yale wasted a lot of money on these brain studies. I doubt I'd score that high on an IQ test with all those tricky brainteaser puzzles, which involve neither nakedness nor dancing.
But - I am very impressed with whatever science must be behind this moving image.
If you see this lady turning in clockwise you are using your right brain.
If you see it the other way, you are using left brain.
Some people do see both ways, but most people see it only one way.
If you try to see it the other way and if you do see, your IQ is above 160 which is almost a genius.
Then see if you can make her go one way and then the other by shifting the brain's current.
BOTH DIRECTIONS CAN BE SEEN
and its functions. Only 14% of the US population can see her move both ways.