Facial expressions don't tell the whole story about a person's emotions, say OSU researchers

If you’re hoping to better understand people, their facial expressions may not be as reliable of an indicator of someone’s emotional state, according to new study by researchers at Ohio State University and other organizations.

The group, led by Aleix Martinez, a professor of electrical and computer engineering at Ohio State University, explored the question of whether or not emotion is actually detectable from facial articulations. Martinez told the attendees of the annual meeting of the American Association for the Advancement of Science in Seattle on Feb. 16, that the answer is “no.”

In studying the kinetics of muscle movement and comparing those movements with emotions, the team found that attempts to define what a person was feeling based on what their face showed were almost always incorrect.

"Everyone makes different facial expressions based on context and cultural background," Martinez said, as reported by Science Daily. "And it's important to realize that not everyone who smiles is happy. Not everyone who is happy smiles. I would even go to the extreme of saying most people who do not smile are not necessarily unhappy. And if you are happy for a whole day, you don't go walking down the street with a smile on your face. You're just happy."

The danger of believing that you can tell what someone is feeling based on what you see on someone’s face is that it’s possible to miss how they’re really feeling or what their true intention is and making judgments about their futures, Martinez said.

The team included scientists from Northeastern University, the California Institute of Technology and the University of Wisconsin.

"What we showed is that when you experience emotion, your brain releases peptides – mostly hormones – that change the blood flow and blood composition, and because the face is inundated with these peptides, it changes color," Martinez said.

There are other hints too, like context, and cultural biases can play a role in hiding what an individual actually feels.    

Martinez says it's important to remember that you’ll never been 100 percent accurate in judging what someone is feeling based on their facial expressions, even with technology, and that deciphering intent goes far beyond facial expressions.