Experimental Psychology: Human Perception
by Jeff Sickles
In pyschology and the cognitive sciences, perception is the process of acquiring, interpreting, selecting, and organizing sensory information. (At least, that’s how wikipedia defines it)
As a small experiment of perception I want show you a brief video during which you will count the number of times a basketball is passed - seems easy enough, right? Okay, follow these short steps and then we’ll discuss it..
1.While watching the following video, ignore the team in black - they are trying to confuse the situation. Count only the number of passes made by the team in white t-shirts.
2.When you are done, click the back button to return to this page with the answers and follow up discussion.
3.Alright, go Watch the Video by clicking here
YouTube - selective attention test
Do not be reading below this point if you haven’t yet watched the video…
Well, how did you do? Did you concentrate?
How many times was the basketball passed among the members of the white team?
Were you also able to count the number of passes among the black team? That’s okay, you weren’t asked to.
Did you see anything else in the video, perhaps a cat, small lizard, or a gorilla?
No, really - did you se the gorilla?
Regardless of what you did or did not see, you should go post your results in the comments below. A vast majority of people (if telling the truth) probably did not observe the gorilla that showed up in the middle of the basketball frenzy, this can be attributed to perceptual blindness. Now, if you are really embarrassed about your inability to see the gorilla, you may post anonymously so that you can feel like no one knows who you are. But honestly, I’m interested to know the results. And if you’ve seen this video before - state that in your comment too. This isn’t a new concept, infact even this test has been around for a while.
Perceptual blindness — including related phenomena is known as inattentional blindness and change blindness. When people are engaged in an engrossing task, such as monitoring swimmers in a pool, they often fail to notice otherwise obvious events because they happen outside the immediate focus of attention.
This is a good example of how people who have seen a car accident or a mugging can come up with such different stories - their attention can be focused on any number of visual stimuli, where they are otherwise cognitively engaged. How about talking on the cell phone? Strikingly, those involved in these crashes usually have no idea there was an object there, and cannot explain their failure to have seen it. Scarry - but I’m sure you’ve experienced the same type of thing, even if it didn’t result in an accident. Ever forget how you got from point ‘A’ to point ‘B’ or somehow can’t recall a portion of your drive home.
Real-life case studies of this blindness include drivers running over bicyclists, train engineers plowing into cars, submarine pilots surfacing under ships and airline pilots landing on other planes. In each case, the object or obstruction should have been easily noticed but was not.
Scientists have been researching this “inattentional blindness”, and other similar phenomenon - and the theory seems to be that there is no perception without attention.
The right number is (I think) 14. But that’s not really the point.
The point is this: did you see the gorilla walk across the screen and beat its chest? According to the original research (you can read it here), there’s a fifty-fifty chance you didn’t. Which fifty are you?