Follow the link to try this experiment.
When viewing the video, see if you can count the total number of times that the people wearing white pass the basketball. How many passes?
http://viscog.beckman.uiuc.edu/grafs/demos/15.html
Then watch it again.
More at http://viscog.beckman.uiuc.edu/djs_lab/demos.html
My comments coming in the post titled “Experiment Results.”