Every February Penn State’s Dance Marathon or “THON” packs thousands of people into the Bryce Jordan Center in order to dance for children with pediatric cancer, and this year I was on a committee called DAR or Donor Alumni Relations. Our committee gives mostly tours and often we have a lot of down time to simply go into the stands and watch THON casually together. Each of the tours crosses the floor twice once in the beginning of the tour and once near the end. People on tours can become astray in the crowd easily, and it can be very hard sometimes to locate lost donors, parents, and in our case committee members. Unfortunately, one girl was lost we will call her “Jesse” to protect the privacy of the individual, and one tour guide simply mentioned that she didn’t return to the concourse and no one has been able to find her on the floor.

During downtime, many of the committee members were in the upper bowl of the BJC watching THON, and we were trying to locate her if possible. One of my friend’s called our search “Where at THON is Jesse” in honor of the game “Where is Waldo”. It was very fitting, because in the sea of hundreds of dancers, moralers, and pass list holders we were looking for one specific person. Be it as it may, the moment that my friend mentioned trying to find her, I see her in the upper right corner of the floor standing with what seemed to be two other dancers. I told everyone the approximate location where I saw her with some context clues, and they immediately began to see her as well. How is it that humans can notice people so far away but also mixed with a large crowd?

This phenomenon is weird, because in reality the brain only sees detail from a very small portion of the retina called the fovea. The retina is located in the back of the eye and contains photo receptors that converts light images into electrical signals that are sent to the brain.  You see less and less detail the further the object’s images is from the fovea. If you extend your arm at full length and take a look at the width of your thumb, that is on average the size of your fovea. This is the only portion of your perceived surroundings that you can see in detail at a particular time. The human eye moves constantly, so that is why it appears we have full detail of everything all the time. Additionally, there are theories that humans recognize objects by a list of features and shapes that are stored in memory. Jesse was wearing a blue THON 2014 DAR committee shirt, she has brown skin, and she has very long black hair. Using these features and the fact that many objects on the floor were far enough away that their whole image was the size of our thumb, or lied entirely on our fovea, we were actually able to recognize people very far away in the large dancer crowd. Later, it was confirmed by one of our captains that it was indeed Jesse on the floor who we had spotted.