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My favorite visual illusion

August 31, 2007

coglanglab's picture

Even if you've seen this beore, it's worth seeing again. The following link is to a video of two teams (white and black) playing a ball game. Your task is to watch the white team and carefully count how many times they pass the ball (concentration is important):

http://viscog.beckman.uiuc.edu/grafs/demos/15.html

Now, watch it again, paying attention to everything on the screen. Most people will notice something they did not see the first time when they were just watching the white team. (This is hard to do in a blog, without spoilers!)

This gets back to my previous posts about how attention affects how you perceive what you see. The professor that designed this, by the way, is Daniel Simons of the University of Illinois. He's produced a great deal of fantastic research; this is just one example. In a random small-world coincidence, he was the previous tenent of the office suite I worked in last year at Harvard.

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Comments

very cool

September 2, 2007 by Anonymous (not verified), 1 year 43 weeks ago
Comment id: 24777

I think that's an awesome experiment... watching it the second time and seeing the quite obvious anomaly it blows me away that I didn't notice it at first

Funny everytime

September 2, 2007 by Louis Choquel (not verified), 1 year 43 weeks ago
Comment id: 24768

Thanks for the link. Sadly they use this stupid applet to display the video sooo scared to be pirated I guess, although it could be ripped very easily with a screen capture tool.

But the test is great, I really didn't see the intrusion at all when I was counting the ball. Actually I must admit I was concentrating on finding anomalies in the ball's movement...

Typo

September 1, 2007 by Anonymous (not verified), 1 year 43 weeks ago
Comment id: 24763

...he was the previous tenent of the office suite I worked in last year at Harvard...

Tenant is spelled with an "a."

Agree with comment

August 31, 2007 by Paul L. (not verified), 1 year 43 weeks ago
Comment id: 24761

I saw numerous things and had no trouble counting how many times the ball passed or the "anomaly". However, I tried to go back and count how many time the black team passed the ball and found it to be a little tougher. But, I agree, definitely not worth a post nor the download time.

Soo..

August 31, 2007 by Eric B. (not verified), 1 year 43 weeks ago
Comment id: 24756

Concentrating blocks out distractors? Errr... Isn't that why we concentrate? I mean, I guess I understand the concept of "your mind does x" but this is hardly worthy of a post. If I exclude all other things from my input than that which I want to measure, aren't I, by virtue of the act, expected to miss things?

Now, if you had claimed that even superficial concentration results in high percentage of peripheral data being lost then I would say "ok..." But this only works if you attempt exclusion of all else. I was able to count the ball passings AND notice the anomoly quite easily - barely any effort. I fail to see what this proves other than "if you concentrate on comething, you only see that one thing..." which is the point of concentration in my mind...

Eric



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