People can read your emotions even if your facial movements don’t give them away, a new report has found.
The study details a previously unknown connection between emotional facial expressions and the central nervous system.
Researchers constructed computer algorithms, based on the new findings, that can recognize human emotions by analyzing facial color patterns.
New research suggests that humans can read other humans’ moods based on facial colors alone – but that AI can do this more accurately than people can. Scientists developed AI that can predict what emotion a person is experiencing based on their facial colors alone
Cognitive scientist and Ohio State professor Aleix Martinez explained how the report informs our understanding of the connection between our feelings and our anatomy.
Professor Martinez said: ‘We identified patterns of facial coloring that are unique to every emotion we studied.
‘We believe these color patterns are due to subtle changes in blood flow or blood composition triggered by the central nervous system.
‘Not only do we perceive these changes in facial color, but we use them to correctly identify how other people are feeling, whether we do it consciously or not.’
The research team responsible for the new report, published in the Proceedings of the National Academy of Sciences (PNAS), is in the process of patenting their new computer algorithms.
The report said the team members hope their work inspires future artificial intelligence that can read and imitate people’s facial expressions.
Previously, Professor Martinez’s team had identified several facial expressions that are produced via unique muscle movement patterns.
But the new research is different because it focuses solely on how facial color changes communicate emotion without any muscle movement.
The researchers analyzed hundreds of photos of facial expressions for the study.
The images were separated into color categories, and, by way of computer analysis, the researchers learned that people expressing emotions such as ‘sad’ or ‘happy’ show unique color patterns.
The scientists determined that the amount of a certain color on a person’s face – as well as the color’s positioning – speaks volumes about the person’s attitude. Above, the face is shown as it was originally photographed
The study said: ‘Regardless of gender, ethnicity or overall skin tone, everybody displayed similar patterns when expressing the same emotion. To test whether colors alone could convey emotions – without smiles or frowns to go along with them – the researchers superimposed the different emotional color patterns on pictures of faces with neutral expressions.
‘They showed the neutral faces to 20 study participants and asked them to guess how the person in the picture was feeling, choosing from a list of 18 emotions.’
These emotions included simple ones, such as ‘sad’ and ‘happy’, in addition to complex ones, including ‘sadly angry’ or ‘happily surprised’.
Professor Martinez admitted that the images looked bizarre, but he said that the participants’ guesses were mostly correct.
The report said that nearly 70 percent of the time participants guessed correctly when shown a neutral face overlain with the colors representing happiness.
They guessed correctly for faces supposed to be ‘sad’ 75 percent of the time, but their corresponding success rate for ‘angry’ was 65 percent.
‘They perceived the emotion even though their only clue was the color superimposed on the face with no facial movements,’ the study said.
A smiling person with red cheeks and temples and blue around their chin is presumed to be ‘happy’, the new study said. The researchers have enhanced the colors to emphasize this
After that, the researchers showed the participants facial expressions representing sadness, happiness and other emotions, but, this time, the colors of some of the images were mixed up.
‘For example, they sometimes took a happy face and put angry colors on it or vice versa,’ the report explained.
The study participants detected that something was ‘off’, though they were not completely sure what was weird about the images.
Professor Martinez said: ‘Participants could clearly identify which images had the congruent versus the incongruent colors.’
This led to the development of algorithms capable of guessing a person’s emotion based on their face color, and, in fact, the technology was more accurate than were the human study participants.
‘Given photographs of people expressing emotion, the computer could match face color to feeling better than the human study participants could,’ the report said.
The computer’s success rates were 90 percent for ‘happiness’, 80 percent for ‘anger’, 75 percent for ‘sadness’ and 70 percent for ‘fear’.
The report said the technology can be used to inform research among various fields including cognition, computer science, neuroscience and human evolution.
It stated: ‘Language is replete with idioms that equate face color to emotion. When we argue until we’re “blue in the face”, we’re angry. If we look “green around the gills”, something has triggered our disgust…This study shows that there is some physiological truth to these old sayings, though the color scheme of human emotion is not as simple as a monochromatic blue, green or red.’
WHAT ARE THE 27 DISTINCT EMOTIONS HUMANS FEEL?
In a recent study, researchers at UC Berkeley found there are 27 distinct human emotions.
It was originally thought we feel just six emotions.
Researchers asked more than 800 participants to freely report or rank the emotions they felt after watching 30 short video clips.
In addition to happiness, sadness, anger, surprise, fear, and, disgust, they also determined confusion, romance, nostalgia, sexual desire, and others to be distinct emotions.
The full list inclues:
The researchers learned that the amount and location of hints of green, blue, red and yellow around the face can reveal one’s emotions.
For example, they found that disgust can be characterized by a blue-yellow shade around one’s lips combined with a red-green shade about the forehead and nose.
‘It’s all the more impressive, then, that our brains are able to decipher the meaning of these color arrangements in an instant. We see a smiling person with red cheeks and temples (with a little blue around the chin) and we automatically read their emotion as “happy”. But the same face with a slightly redder forehead and slightly less blue chin registers as “surprised”,’ the study said.
The study pointed out the fact that humans might be the only primates with the ability to read emotions based on facial colors, though this is hard to know for sure considering the faces of other primates are covered in hair.
This raises the question of whether or not humans’ relatively bald faces are the results of evolutionary changes.
The study explained: ‘The fact that we evolved much less facial hair than the apes suggests that our early ancestors may have found some advantage to letting their blushes show.’