A watch is a fairly common item, and most people wear one. That’s what makes this experiment so easy to do – especially with people who aren’t expecting it.
Ask someone to describe their watch to you. They are allowed to look at it and try and remember every detail. Ask them to remember what style the numbers are, the colour of the face and the colour of the watch strap. Ask them to remember the shape of the hands, and the details of any other dials or day and date information. They’re allowed to look at their watch for as long and as intently as they like.
When they’ve stopped examining their watch ask them what time it is. Most people will be stumped, and will have to look at their watch again. Besides making them foolish what’s going on there?
It’s called inattentional blindness, and it happens when we’re engaged in an absorbing task. Some scientists believe that it’s because we are so engaged in the details of the watch that we choose not to look at the time. Others say that we take in the time along with all the other information but filter it out.
Whatever the actual mechanism in the brain inattentional blindness is what made a gorilla effectively invisible in one of the most famous psychology experiments.
People were asked to watch a film of a basketball match and to count the number of passes. During this a woman in a gorilla suit walked through the game in full view. The gorilla was only seen by half of the people who watched the film, and the more attention they paid to the number of passes the less likely they were to see it.
Inattentional blindness isn’t a fault or a failing. Without our ability to filter out and ignore information every day would be chaos, and magicians wouldn’t be able to misdirect us. It’s only when we try and deny it, like texting whilst driving, that it becomes dangerous.
If you found this experiment with a watch interesting why try one with a paintbrush and a rubber glove. Or why not sign up for my monthly newsletter here with three stories every month on the quirky side of psychology and relationships.