[MUSIC]
[SIMONS] I am Dan Simons. I am a professor in the Psychology department at the University of Illinois
and I also have an appointment at the Beckman Institute for Advanced Science and Technology.
My research here focuses on visual cognition -- what we see, what we don't see,
how much of our visual world we are aware of,
and how much we remember from one moment to the next.
One of my best known studies was done with my collaborator Chris Chabris some years ago.
And it was based on some much earlier work by our colleague Dick Neisser.
And what we have is a video in which people were passing basketballs.
So three people were wearing white shirts and they were passing a ball.
And your task, when you were watching the video, was just to count how many times
those three players passed the ball.
We also had three players wearing black shirts passing their own ball.
And you were supposed to ignore their passes.
So as you are doing this task, after about thirty seconds, we would have a person wearing
a full-body gorilla suite walk into the middle of the scene, stop in the center,
turn and face the camera, thump its chest, and then walk out the other side...
...a total of about nine seconds later.
And what we find is that about half the people who do this simply don't notice the gorilla.
[GORILLA] When Dan asked me to be a part of this experiment, I thought...
"No Way! People are totally going to see me. I am a 400 pound gorilla!"
[SIMONS] We will ask them afterwards, "How many passes did you count?"
Which they generally get pretty close to right.
We then asked them, "Did you notice anything unusual?"
"Did you notice anything other than the players?"
"Did you notice anything walk though the scene?"
And they will say, "No."
Then we asked them, "Did you notice a gorilla?"
And their response is typically, "A what?!"
[GORILLA] So this Simons guy says, you know, "We can show you and not everyone is going to see you."
Yeah, right!
How can people not see me? I'm huge! I'm ferocious! I'm a four hundred pound gorilla!
What was he thinking?
We rewind the tape and show it to them again and their reaction is typically, "I missed that?"
It's shocking that you could possibly miss something as obvious as a gorilla.
Of course the people who noticed the gorilla are shocked that anybody could possibly have missed it,
because it's right there in front of you.
[GORILLA] I walk in there. I walk in the middle of all these kids running around throwing this ball around.
I stand there. I thump my chest. Not once. Not twice. But three times I thump my chest.
That's scary, man! What else are people going to look at?
You know, I'm big, I'm a gorilla, and they don't see me.
What's up with that?
[SIMONS] This is the intuition we have, that if something important or distinctive or unusual --
like a person in a gorilla suit -- walks into our field of view, we'll automatically notice it.
The reality is that only about half the people do.
About ninety percent think they will.
[GORILLA] People are just so focused on counting those passes that they don't notice me.
You know, I'm not trying to be subtle here!
[SIMONS] Even more remarkable, my colleague Daniel Memmert used the gorilla video in a study
in which he had people wearing an eye-tracker.
And what that does is tells you exactly where they are looking at as they are watching this
video and counting the passes by the team wearing white.
And what he found was that the people who missed the gorilla looked at it for up to a second.
So they looked right at it, but still didn't see it. Looking isn't the same as seeing.
We have to focus attention on something in order to become aware of it.
[GORILLA] [SIGHS]
How do you think it makes me feel?
You know... I'm trying to be intimidating.
It makes me feel...
...inadequate.
[SIMONS] The most consistent question we get is,
"Are there some people who consistently notice the gorilla and other people who don't?"
So, are there 'Noticers' and 'Missers' among us?
And the reality seems to be no. That it is largely just a matter of a flip of the coin.
We know when we've noticed something unexpected.
But we are not aware of the times when we have missed something unexpected.
The failure to notice people in gorilla suits is really a natural byproduct of something that we do quite well,
and that is very important to us, which is focusing our attention.
We need to be able to filter out the distractions from our world and not let them interfere
with our ability to do the task of trying to do.
The key is that, when you are focusing your attention on one aspect of your world,
you do not have an unlimited amount of attention to devote to other things.
And we only see those things that the focus our attention on.
The problem is that, on occasion, we filter something that we might want to notice.
And we do not realize that we are doing that.
That sort of mismatch between what we see and what we think we see
is a really profound one that has all sorts of consequences for our daily lives.
[MUSIC]
[GORILLA] [SIGHS]
Okay, I admit it.
I didn't see me either.