Smile more

This is a fascinating look at the science of studying facial expressions, but I found this nugget expecially interesting:

[some guy] received his most memorable lesson in this truth when he and [some other guy] first began working on expressions of anger and distress. "It was weeks before one of us finally admitted feeling terrible after a session where we' d been making one of those faces all day," [] says. "Then the other realized that he'd been feeling poorly, too, so we began to keep track." They then went back and began monitoring their body during particular facial movements. "Say you do A.U. one, raising the inner eyebrows, and six, raising the cheeks, and fifteen, the lowering of the corner of the lips," [] said, and then did all three. "What we discovered is that that expression alone is sufficient to create marked changes in the autonomic nervous system. When this first occurred, we were stunned. We weren't expecting this at all. And it happened to both of us. We felt terrible . What we were generating was sadness, anguish. And when I lower my brows, which is four, and raise the upper eyelid, which is five, and narrow the eyelids, which is seven, and press the lips together, which is twenty-four, I' m generating anger. My heartbeat will go up ten to twelve beats. My hands will get hot. As I do it, I can't disconnect from the system. It's very unpleasant, very unpleasant."

[], [], and another colleague, [], who teaches at [], published a study of this effect in Science. They monitored the bodily indices of anger, sadness, and fear -- heart rate and body temperature -- in two groups. The first group was instructed to remember and relive a particularly stressful experience. The other was told to simply produce a series of facial movements, as instructed by [] -- to "assume the position," as they say in acting class. The second group, the people who were pretending, showed the same physiological responses as the first. A few years later, a German team of psychologists published a similar study. They had a group of subjects look at cartoons, either while holding a pen between their lips -- an action that made it impossible to contract either of the two major smiling muscles, the risorius and the zygomatic major -- or while holding a pen clenched between their teeth, which had the opposite effect and forced them to smile. The people with the pen between their teeth found the cartoons much funnier. Emotion doesn't just go from the inside out. It goes from the outside in. What's more, neither the subjects "assuming the position" nor the people with pens in their teeth knew they were making expressions of emotion. In the facial-feedback system, an expression you do not even know that you have can create an emotion you did not choose to feel.

So yeah. Smile more. Your well being may depend on it.