“Sometimes your joy is the source of your smile, but sometimes your smile can be the source of your joy.” ~Thich Nhat Hanh
"The French neurologist Guillaume Duchenne mapped 100 facial muscles in 1862. He pointed out that false, or even half-hearted, smiles involved only muscles of the mouth. But "the sweet emotions of the soul," he said, activate the pars lateralis muscle around the eyes.
Since then, physiologists have talked about the Duchenne marker in a smile. It's a slight crinkling of crows-feet and a droop in the eyelid toward the temples -- along with a lift of the cheeks and the corners of the mouth. You know the sign. You recognize true delight in a friend's face.
Now psychologist Paul Ekman has gone back to the smile and found out something very important about it. The Duchenne smile, it seems, is accompanied by increased activity in the left prefrontal cortex -- known to be the seat of positive emotions." ~by John H. Lienhard, The Engines of Our Ingenuity
That's right, the very act of smiling activates neurons in your brain that can help elevate your mood. Sounds absurd, but it's true. And, Duchenne would argue that you can sense when someone is just pretending to be happy or if they're pretending to be glad to see you just by looking at them. A few years back, I wrote here about how what joy really is, is being connected to others, being in relationship. Duchenne, Ekman and Lienhard would probably agree that joy is that "I'm so glad to see you" glint in one's eye.
No wonder the blessing in Numbers 6:24 says "may God's face shine upon you, smile on you, and look favorably upon you." I know when my children are excited that I've come home from work it makes my face "light-up." God is always glad to be with us, He loves us so much, just thinking about us makes Him happy.
Psychologists recommend interacting with others rather than isolation when we're depressed. No wonder. Joy is about feeling connected and unconditionally accepted.
But it's not just something you receive. Joy is one of the greatest gifts that you can give. Doctors and scientists have also discovered a thing called "mirror neurons." When you see someone with a genuine smile, it triggers the smile neurons in your own brain. When your parents warned you that if you lie down with dogs, you pick up fleas, they mean that if you hang out with negative people, you pick up negative attitudes yourself. If you're having trouble with the blues, surround yourself with positive, upbeat people and sooner or later, you'll probably start to come around too.
Likewise, if you want to affect the emotional climate around you, smiling and being positive is a great way to start.
“There is now compelling evidence that smiling causes people to feel happy. Requiring people to smile, no matter how they really feel at first, results in increased positive feelings; frowning conversely decreases positive feelings. Robert Zajonc and his colleagues show that smiling leads to physiological changes in the brain that cool the blood, which in turn makes people feel happy." ~Gretchen Rubin, The Happiness Project
Anderson, C.A. “Temperature and Aggression: Ubiquitous Effects of Heat on the Occurrence of Human Violence”, Psychological Bulletin 106 (1989): 74-96.
Zajonc, R. B., S. T. Murphy, & M. Inglehart, “Feeling and Facial Efference: Implications of the Vascular Theory of Emotion” Psychological Review 96 (1989): 395-416.