Many years ago came across a study that spoke about all the tiny muscles around the mouth and how smiling engaged those muscles in a particular way resulting in a release of endorphins, natural pain killers and serotonin. It also lowers blood pressure and boosts the immune system. In addition, in the 1980s, some interesting studies on the physiology of smiling brought it back into the consciousness of the psychology field. One study found that when subjects contorted their faces to indicate fear, their body temperatures increased and their pulses sped up. Dr. Zajonc’s research took this observation further, into a full-fledged proposal for why a smile might trigger happiness. It basically goes like this: When the temperature of any body part changes, the chemical activities connected with that area also change. Therefore, when facial muscles are activated in an expression, the biochemical processes associated with those areas of the face are altered according to their temperature change. And research suggests that a cooler brain creates good emotions, while a warmer brain produces negative emotions [source: Goleman].
Zajonc points to the part of the body called the internal carotid artery, which is the “pipe” that delivers the majority of blood to the brain. This artery flows through an opening called the cavernous sinus, which contains lots of facial veins. When someone smiles, causing certain facial muscles to stretch and tighten, veins are constricted. This would cut down on the blood flowing to the cavernous sinus, which in turn would reduce the amount of blood flowing through the carotid artery to the brain. Less blood volume means the temperature of that blood drops. When that cooler blood gets to the brain, brain temperature would drop, too, triggering a happy feeling. The theory works in reverse, too: Zajonc says that when the muscles involved in a frown tighten, the result is increased blood flow to the cavernous sinus and, by extension, a warmer brain. So, if Zajonc is right — and not everybody thinks he is, but it’s an interesting possibility — does that mean you could avoid sadness for the rest of your life by faking a smile?
Definitely not. Even proponents of the theory don’t suggest that smiling can make unhappiness go away. The theory basically states that in a state of emotional neutrality, putting a smile on your face can tip you in the direction of a positive feeling. My experience is that it can actually go further than that. I’ve seen positive effects for a wide spectrum of starting negative emotional states, not just neutral ones. Suffice it to say that if you are already happy it simply enhances the happiness. The smile can be forced or not, either way it works.
So many years ago I decided to put it all to the test. I started putting a small smile on my face while meditating, much like we see in pictures of the Buddha. I was pleased with the results so started ending my MBSR classes with an exercise I made up one day. At the end of class we all spend 60 seconds putting on a big smile and noticing what is going on physically, mentally and emotionally much like we do in a mindfulness practice. After 60 seconds we go for another 60 seconds with that same big smile and same mindful attention only this time making eye contact with everyone in the class. So that’s a 2 minute exercise and the results have been impressive. I have continued for over 20 years to do this class ending exercise and it continues to be a high point of everyone’s experience.