Twirling Ballerina Cognitive Trick

This intriguing video has been making its rounds on various blogs and forums lately, and has become a rather contentious issue amongst a few friends and I. The website that hosts the video purports to tell you whether or not you are a right or left brained person based on the directional spin you see the animated female twirl. When I first watched it I was alone and only saw it twirling in one direction, clockwise, but after a few minutes passed the mysterious female reversed her twirl, and began spinning counter clock-wise. I figured it was programmed to reverse its twirl after a certain amount of minutes had passed, but later I watched the same video with a handful of friends, and two of us argued, passionately, that she was twirling counter-clockwise, while three of my other friends argued, just as assuredly, that she was twirling clockwise. This is incredibly weird indeed and I have yet to figure out how it works or what makes your mind switch the motion in which you perceive it to be twirling. Thus far my theories have been pretty tentative and speculative.

Which reminds me, there is another video I had watched a while back that was extremely cool/mind blowing, as it revealed just how much the mind often misses.

Before you click start on the video the task you are asked to perform is to count the amount of times the people wearing the white tee-shirts pass the basketball to one another. See if you can follow the ball and get the right amount of passes. It's hard.

http://viscog.beckman.uiuc.edu/grafs/demos/15.html

Post the amount of passes you counted in the comments section below and I will tell you if you were right.