Serendip is an independent site partnering with faculty at multiple colleges and universities around the world. Happy exploring!

Reply to comment

emily's picture

Gorilla Graphs

After reading the article in from the nature journal about magic tricks, I was reminded of the experiment (because it was mentioned) on unintentional blindness where people are supposed to count the number of passes a certain team makes and will not notice that a big gorilla walks through the scene because they are focusing so much on counting. I decided to send that video to people (http://viscog.beckman.uiuc.edu/flashmovie/15.php) along with my survey about it and told them the following:

"Please watch the following video clip.

this is a video clip of two different teams passing a basketball around.

focus VERY CAREFULLY on how many passes the team in the black shirts makes and make sure to count the passes.
the following survey will ask you how many passes they make along with a few other questions."

The survey asked 5 questions. question 1 asked the participant to state how many passes the team he or she was watching made. The second asked if they noticed the gorilla that walked through the middle of the players (yes, no). The third asked "If yes, have you seen this video before?" (Yes, No, I did not see the gorilla). Question four asked "If yes but you have not seen this video before, did you accurately count the number of passes made?" (Yes, No, I have already seen this video, I did not see the gorilla). Question five asked the participant, if they did not see the gorilla, to watch it again and rate how surprised they were to have not seen it at first (Not surprised, somewhat surprised, very surprised, utterly speechless, I have already seen this video, I did not see the gorilla). 

After 10 people had taken it, and every single person had seen the gorilla (when we did it in my psych class last year, only another girl and me saw the gorilla because we were not paying attention to counting...everybody else missed it!), I realized that something was wrong with the way I was conducting my experiment. I decided to send out my survey again, only this time asking the new participants to count the passes made by the team in the white shirts, not the black shirts as before. I was wondering if the black gorilla was getting caught by people's eyes who were watching the black shirts. However, everyone there too saw the gorilla. I have concluded that the way which this video was presented, online in an email, greatly inhibited my results. If I were telling the participants in person to really focus on the passes made, I could make my voice sound really important and probably make them focus more, as my psych teacher did to my class. However, the fact that the video was presented so impersonally made people not focus that much on the counting. This is shown in my graphs:

The first graph just shows that almost everyone saw the gorilla, except for one person counting the black shirts. The second graph just shows what percent of those who saw the gorilla had not seen the video before, because once you see the video once you are sure to see the gorilla the second time you watch it because you will not be concentrating on the passes as hard or you will know the gorilla is there. The third graph, however, is the most interesting to me. This shows that the majority of the people who had not seen the video already did not count the passes accurately. This shows that they were not focusing extremely hard and therefore probably noticed the gorilla (the person who did not see the gorilla left question 3 and 4 blank for some reason, so they are not represented on those graphs). My last graph just shows that the person who did not see the gorilla was "very surprised" that he or she did not see it. 

Reply

To prevent automated spam submissions leave this field empty.
10 + 2 =
Solve this simple math problem and enter the result. E.g. for 1+3, enter 4.