A recent study conducted by a research team from the University of New York reveals how many faces the average mind retains in memory. To get a rough idea of the average person’s “facial vocabulary,” research was conducted with 25 people. There were 2 phases to the experiment.
All the participants were given one hour to list as many faces as possible from their personal lives. Again, they were given an additional hour to list all the famous faces they could remember including politicians or anyone they may have seen through any form of media. With both lists, even if they couldn’t remember a name, they were permitted to list the face as a description. For example, “my high school math teacher,” or “the bald man with green eyes that lived down the street,” or “the main actress in the movie There’s Something About Mary,” etc.
Within the first minutes the participants were on a roll quickly listing names. Over the course of an hour the rate of remembrance dropped. By graphing this relationship and extrapolating it to the moment when most people would run out of faces, the researchers were able to calculate an estimate to the number of faces an average person can recall from memory.
The participants were shown photographs of 3,441 celebrities, including presidents or any public figure in the media. Two photographs of each celebrity were revealed and both had to be recognized in order to qualify. This phase of the testing was done to figure out how many additional faces the people recognized even though they had been unable to recall them without prompting.
Dr. Rob Jenkins, from the Department of Psychology at the University of York, said: “Our study focused on the number of faces people actually know- we haven’t yet found a limit on how many faces the brain can handle.”
The lists from phase 1 and 2 were then united. From the two sets, any duplicate faces were canceled out and the rest of them merged together to get a combined total number of recognitions. The conclusion came to be that the average human knows about 5,000 faces. The researchers reported in the Proceedings of the Royal Society B that all 25 participants in the study recognized between 1,000 and 10,000 faces.
Dr. Jenkins added: “The range could be explained by some people having a natural aptitude for remembering faces. There are differences in how much attention people pay to faces, and how efficiently they process the information. Alternatively, it could reflect different social environments-some participants may have grown up in more densely populated places with more social input.”
The mean age of the studies participants was 24 and, according to the researchers, age provides an intriguing avenue for further research. “It would be interesting to see whether there is a peak age for the number of faces we know”, said Dr. Jenkins. “Perhaps we accumulate faces throughout our lifetimes, or perhaps we start to forget some after we reach a certain age.”
Even though this experiment is quite vague about the rate of remembrance and relays on the honesty of its participants, the results provide a baseline quantity for future facial recognition studies, the research team explains.