Humans recognize 5,000 faces, study says

From family and friends to strangers on the subway and public figures on 24-hour news cycles, humans recognize an astonishing 5,000 faces, scientists said Wednesday in the first study of its kind.

Through most of history humans lived in small groups of a hundred or so individuals, a pattern that has changed drastically in recent centuries.

A study by scientists at Britain’s University of York found that our facial recognition abilities allow us to process the thousands of faces we encounter in busy social environments, on our smartphones and our television screens every day.

“In everyday life, we are used to identifying friends, colleagues, and celebrities, and many other people by their faces,” Rob Jenkins, from York’s Department of Psychology, told AFP.

“But no one has established how many faces people actually know.”

For the study, published in the journal Proceedings of the Royal Society B, Jenkins and his team asked participants to write down as many faces they could remember from their personal lives.

The volunteers were then asked to do the same with people they recognized but did not know personally.

They were also shown thousands of images of famous people – two photos of each to ensure consistency – and asked which ones they recognized.

The team found an enormous range of the number of faces each participant could recall, from roughly 1,00010,000. “We found that people know around 5,000 faces on average,” Jenkins said.

“It seems that whatever mental apparatus allows us to differentiate dozens of people also allows us to differentiate thousands of people.”