I stared at this movie for thirty minutes today. It supposedly indicates whether you're using the right side or the left side of your brain, depending on whether you view the dancer moving in a clockwise or counter-clockwise direction.
I immediately assumed she was moving in a _____ direction.
Then I tried to picture her moving in a _____ direction.
Then the test was to figure out how to make her switch directions whenever I wanted. (My personal solution below.)
The movie is on a loop.
If you're familiar with lawn sprinklers, think of her entire motion as like one of those sprinklers that makes high, arcing shots in one direction, and then switches directions and makes rapid-fire, low-to-the-ground shots.
1. At the beginning of the loop, her swinging foot is at 9 o'clock moving clockwise. This is the rapid-fire, low-to-the-ground motion.
2. At 12 o'clock she jumps off with her left foot, and her right foot begins a long, arcing motion.
3. At 3 o'clock she is at the height of her jump. This is where the change occurs. Her right thigh, which should be passing in front of her left thigh (closer to the viewer), instead slips behind the left thigh (farther away from the viewer), and emerges from behind in a counter-clockwise direction. So it's like a satellite coming out from behind the far side of the moon. The trick is to wait until the moment when the two thighs meld together, without any space between them. Then imagine the switch occurring.
(Another way to consider this, in case the thighs aren't distinct enough: When the foot on her extended leg is at 4 o'clock, it immediately teleports up to 1 o'clock, and is now moving in a counter-clockwise direction.)
4. She continues to float slowly to the ground in a counter-clockwise motion, eventually hitting the ground at 9 o'clock. At this point, she immediately switches directions like a sprinkler, churning clockwise and low to the ground until 12 o'clock, at which point she jumps off again.