Smile your mood

How to Lift Your Mood? Try Smiling - TIME

I was skeptical until I read a paper in the January issue of the Journal of Personality and Social Psychology, a peer-reviewed publication of the American Psychological Association. That paper led me to other papers, and it turns out the trainer is right: The face isn't a pressure-relief valve. It is more like a thermostat. When you turn down the setting, the machinery inside has to do less work.

In the Journal of Personality and Social Psychology paper, David Matsumoto of San Francisco State University and Bob Willingham of the Center for Psychological Studies in Berkeley, Calif., present the results of the first study ever conducted comparing the facial expressions of blind people with those of sighted people in a natural, nonlaboratory setting. Those studied were all judo athletes — blind ones who competed in the 2004 Paralympic Games in Athens and sighted ones who competed in the 2004 Olympics in the same competition hall a few weeks earlier. (See pictures of "Second Place: Faces of Defeat.")

Matsumoto conceived the paper to investigate one of the oldest dilemmas in the study of physiology. We have known for many years that people all over the world, even those from remote cultures, use the same facial expressions to convey basic emotions like grief or joy. Charles Darwin noted this phenomenon in the 19th century, and Matsumoto's mentor, a famous psychologist named Paul Ekman who traveled the globe in the 1960s, proved that both isolated tribesmen and urban Westerners identified pictures of facial expressions in the same way. Ekman demonstrated that a frown means unhappiness the world over; wide eyes mean fright or surprise; a wrinkled nose means disgust. But no one has yet found the source of these universal expressions: Do we all learn the expressions through our culture, or are facial configurations genetically coded for everyone?

This question has occupied many scientists. Darwin wrote a long, highly entertaining 1872 book, The Expression of the Emotions in Man and Animals, that came to the conclusion — unsurprising, given the author — that the universality of facial expressions owed to their evolutionary origin.

In his concluding chapter, Darwin noted that a pastor who ran a school for the blind told him that "those born blind" and "those gifted with eyesight" display facial expressions equally well. But somehow it took more than 130 years for someone to test this hypothesis scientifically. Matsumoto has finally proved the hypothesis. He examined 123 photographs taken by Willingham, a professional photographer, and carefully coded all the expressions on the athletes' faces. The authors found that regardless of whether the athletes could see, the gold-medal winners were significantly more likely to display real, joyful smiles — those that engage not just the muscles around the mouth but also those around the eyes — than those athletes who got silver medals. The ones who received silvers, whether blind or sighted, were significantly more likely to display social or lying smiles — those in which only the mouth muscles are engaged. (You can tell the difference between real and social smiles after training in facial movements; once you have the training, it's impossible not to study the eyes whenever someone smiles at you.)

Because blind people can't learn cultural cues from looking at others, Matsumoto and Willingham conclude that all of us are born with the ability to express both real and social emotions through our facial expressions. The fact that blind people display fake smiles shows that the skill is probably one we acquired through evolution in order to get along with others. (See pictures of facial yoga.)

Beyond that, what the genetic origin of facial expressions suggests is that the way your face looks is strongly related to what you are feeling inside. What I began to wonder was whether the train might run in the opposite direction: Could you change what you're feeling inside by pulling your face into a different expression? This is what the trainer had suggested: my exercises would be easier if I kept my face passive rather than twisted.

The possibility that your expression could affect your mood was first suggested to me by Marsha Linehan, a University of Washington psychologist who treats suicidal patients. She has found that helping patients modulate their facial expressions — relaxing the face when angry, for instance — can help them control their emotions. Ekman and his colleagues provided evidence of this in a Science paper back in 1983. They found that those instructed to produce certain facial movements showed the same physiological responses as those asked to recall a highly emotional experience. Later, a study showed that if you hold a pencil between your teeth — causing your mouth to approximate a smile — it will be easier for you to find cartoons funny.

In short, the emotional train does run in two directions: between your brain, which may be screaming from the pain that your trainer is causing, and your face, which can — if you draw it into a relaxed expression — inform your brain that it shouldn't be protesting so much. So next time you're working out and grimacing, push your facial muscles into submission. Look blank. You will find it's easier to get through one more rep.