Families, friends and relatives combined, humans live in groups of about 100. But does this mean our facial recognition abilities are limited to just a few?
Not really – and a new study has found that our brain is outfitted with an ability to deal with as many as faces we encounter every day in the modern world – whether on screens or in social interactions.
The study published in the journal Proceedings of the Royal Society B is the first to provide an evidence-based estimate on the number of faces humans can recognize. It puts the number at a staggering 5,000 on average.
“Our study focused on the number of faces people actually know” says Rob Jenkins, from the Department of Psychology at the University of York in a news release. “We haven’t yet found a limit on how many faces the brain can handle.”
“The ability to distinguish different individuals is clearly important–it allows you to keep track of people’s behaviour over time, and to modify your own behaviour accordingly.”
For the study, researchers recruited 25 participants and asked them to think of as many as faces possible – belonging to their family, colleagues, and famous people – as they could in an hour. The participants, on average, could recall around 550 faces.
The researchers then asked them to review 3,441 faces of famous people. They were able to recognize about 800 faces.
For every participant, the team measured “facial vocabulary” on the basis of the ratio of number of famous people the they recalled to number of faces they recognized. They found that the average number of faces each participant knew was 5,000, while some reached as many as 10,000 faces.
“The range could be explained by some people having a natural aptitude for remembering faces,” Jenkins explains. “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.”
Researchers are yet to figure out the limit to how many faces our brain can handle, or if there is a peak age for the number of faces we can remember.
“Perhaps we accumulate faces throughout our lifetimes, or perhaps we start to forget some after we reach a certain age,” says Jenkins.