Why can't we pay attention?

Here's a great Harvard study on inattentional blindness, the phenomenon where we don't notice objects because we're too intent on something else. I'm really relieved to know there's a name for it; I must be the reigning queen. I can't tell you how many times somebody's told me they blew their horn, waved at me, or tried to get my attention some other way and I never even noticed.

There's a video that gives a good illustration of the point. Read the directions below, then click on the green arrow to start the video. http://viscog.beckman.uiuc.edu/grafs/demos/15.html
Several people emailed me a similar video that was perhaps less obvious and more fun, but I must have been to happy with the delete button this week.

Directions for video:
You will see 2 teams playing basketball. Count the number of times the white team passes the ball. Then click this button and answer the question.