In a classic demonstration of change blindness, Simons and Levin (1997) conducted a field experiment in the city of Ithaca, New York. Participants were chosen at random on the Cornell University campus. In the experiment, an experimenter posing as a tourist asked a person on campus for directions. When the participant started giving directions, two other experimenters, posing as construction workers, passed by carrying a detached door. The construction workers passed between the experimenter who had asked for directions and the participant. At this point, Simons and Levin had the first experimenter hide behind the door and exit the scene, while a second experimenter, the same gender and age as the first experimenter, replaced the first. The question was would the participant notice that the person to whom he was giving directions had changed? It seems obvious—if you were just talking to one person, and he was replaced by another person, of course you would notice the difference. However, this obvious answer turned out to be wrong most of the time.
What do you predict the outcome of experiment will be? Got to the next tab and watch video from this experiment.
You can check out Dr. Simon's website here to see more examples of change blindness.