Researchers have identified a single, universal facial expression that is interpreted across cultures -- whether one speaks Mandarin Chinese or English -- as the embodiment of negative emotion.
This facial expression that the researchers call "Not face" consists of furrowed brows of "anger", raised chin of "disgust" and the pressed-together lips of "contempt", the study said.
"To our knowledge, this is the first evidence that the facial expressions we use to communicate negative moral judgment have been compounded into a unique, universal part of language," said Aleix Martinez, cognitive scientist and professor of electrical and computer engineering at the Ohio State University in the US.
The look proved identical for native speakers of English, Spanish, Mandarin Chinese and American Sign Language (ASL), the researchers said.
The study, published in the journal Cognition, also revealed that our facial muscles contract to form the "not face" at the same frequency at which we speak.
For this new study, the researchers hypothesised that if a universal "not face" existed, it was likely to be combination of three basic facial expressions that are universally accepted to indicate moral disagreement -- anger, disgust and contempt.
To test the hypothesis, they recruited 158 Ohio State students in front of a digital camera. The students, divided in four groups, were filmed and photographed as they had a casual conversation with the person behind the camera in their native language.
In all four groups -- speakers of English, Spanish, Mandarin and ASL -- the researchers identified clear grammatical markers of negation.
The students' answers translated to statements like "That's not a good idea," and "They should not do that."
The researchers manually tagged images of the students speaking, frame by frame, to show which facial muscles were moving and in which directions.
Then computer algorithms searched the thousands of resulting frames to find commonalities among them.
Regardless of language, the participants' faces displayed the "Not Face" when they communicated negative sentences.
