Emotions influence circulation, and therefore coloration, in our faces, helping express how we feel
A perfect poker face may be physiologically impossible. No matter how well someone might try to hide their emotions behind a clenched jaw and vacant stare, they probably won’t be able to control their cardiovascular system well enough to stop changes in blood flow just below their skin. While these shifts aren’t necessarily as dramatic as the pink cheeks many of us get when feeling nervous or embarrassed, they are clear enough to help people read each other’s emotions with up to 75 percent accuracy.
Researchers from Ohio State University found that emotional states changed people’s circulation in their nose, eyebrows, cheeks and chin, and set out to test how much those changes were noticed by onlookers. The slight shifts in color, like a blue-yellow cast around a disgusted person’s lips, are subtle enough that most of us have never consciously noticed them. So computers were used to analyze images and find the patterns that turned up as a person experienced sadness, anger, happiness and more.
Reading emotions without facial expressions
Once those patterns were found, they were used to manipulate photos of people making neutral facial expressions. Those photos were then examined by test participants to see if they could correctly identify what emotion was coloring the otherwise blank expression. Some emotional color-schemes were harder to identify than others, but people definitely detected the correct emotion the more often than not. For example, angry colors were correctly identified 65 percent of the time, while happier hues were spotted 70 percent of the time.
A second phase of testing approached things from the opposite direction. Instead of identifying emotions on blank faces, participants were asked to assess photos were the emotional coloration was purposely mismatched to the expression being made by the face’s muscles. For instance, a rosy chin normally associated with a big smile was digitally added to a photo of someone otherwise expressing despair. Test participants couldn’t put their finger on what was wrong, but they did note that something was “off” with this round of photos, indicating that our brains do look for this kind of information, even if we’re not aware of it.
Communicating with color
These results make sense considering how social and visually oriented human beings are. We spend a lot of time trying to read each other’s faces to form bonds, get signs of danger and more. Even if we don’t take our shifting hues to the extremes of a stressed chameleon, we certainly wouldn’t be the first animal to adjust skin temperatures according to emotional states. Of course, before we pat ourselves on the back for this subtle form of communication, it’s worth noting that the entity that could most accurately read the emotional states expressed by skin coloration was a computer. Once it was trained on what to look for, image analysis was able to identify a happily-colored face with 90 percent accuracy.
Source: Happy or sad, the colour of your face reveals how you feel by Haroon Siddique, The Guardian