Here's an example. The video below was constructed by overlaying two different movies, each of a team of three people passing a basketball back and forth. All the people from the first filming wear black shirts and all those from the second wear white. Your task is to watch carefully and count the number of passes made by the players watching the black shirts. See if you can manage it!
Don't read further until you've watched the video...it's only 18 seconds long.
No, I mean it! Go watch the video.
Did you manage to track the passes? Did you see the woman with an umbrella walk across the screen? Our class of highly-motivated executives got the count right, but only one person (out of about eighty) saw the woman with the umbrella. So the next time your spouse says, "I already told you that!" don't be so sure they didn't.
There was a lot more to it and the discussion of cognitive bias was really interesting. I'll probably come back to it in a couple of weeks but since I can't cover everything in the course in real time I'm going to move on to things more directly tied to negotiations. You can learn some examples of cognitive bias at a blog that shares the name of this post, but again, if you ever get the chance to see Mahzarin...take it.