I think the fine folks at NCBI ROFL covered this one recently, but it's too good not to share.
Have you ever been in a terrible mood, and someone tells you to smile? It usually doesn't make your mood any better to be TOLD to smile, but what if you actually DO smile? Does it help?
Well, according to this paper, actually smiling may really help. But if you're holding chopsticks in your mouth in a truly ridiculous manner, can you really HELP feeling a little better about life?
Kraft and Pressman. "Grin and Bear It : The Influence of Manipulated Facial Expression on the Stress Response" Psychological Science, 2012.
There are some scientists who have spent a lot of time analyzing people's smiles. Specifically, whether smiling more is actually good for you. For example, they have found that people who take more photos when they are smiling then to have better health than those who don't. However, I notice there's no control here for whether people who smile more in photos have things like more friends, more people asking flatteringly to take their photo, or heck, more photogenic faces (also, I should note, no research has been done on the potential health benefits of duckface).
But it appears in general that smiling, whether you're forced to do it (by people positioning your face) or asked to, can generally influence your attitude, making you rate things as funnier.
But can it HELP? Can smiling specifically help, say, stress? To look at this, the authors of this study prepared to force some smiles. Preparation presumably involved bulk purchase of disposable chopsticks.
Why chopsticks? Well you have to manipulate the smiles, you see. As the authors wisely note:
Facial-expression researchers have long agreed that not all
smiles are equal.
Basically, there are two types of smile, the kind of awkward, forced one that you put on for some family photos and the times when you really don't want to see your colleagues, and the happy, real, BIG genuine smile that appears on you when you finally see a friend you've wanted to see for a very long time. The lame smile is called the "standard" smile, while the big one is called the "Duchenne" smile (though I can't figure out why it is called that, it specifically involves lifting the cheek muscles).
To make the participants slap on a smile, the authors of the study 170 students hold chopsticks in their mouths, telling them it was a study on multitasking. Some were told to just hold them in their teeth. The second group was told to hold them such that they got a small standard smile. The third was instructed to hold them in way that gave them a big Duchenne smile, with the final result looking like it might induce a headache if you hold it long enough.
To control for awareness, half of each smiling group was told to smile, but the other half was not.
Then they made all their participants perform a really stressful, very frustrating task (I've done it, it's frustrating). You have to put your non-dominant hand in a box where you can't see it. Then you have to try and trace a star. While you are doing this, you are looking at the mirror image of the star and your hand. It's...frustrating in the extreme. They also received a pain stress test involving submerging your hand in cold water. During both of these tests they looked at the heart rate, specifically how fast the heart rate recovered following the stress.
Here you can see the heart rate recovery rates following the stressful condition of having to trace a star. While the statement of the statistics is...overly confusing and not particularly helpful for the findings (p=0.06 is apparently "marginally significant". Well played. And all analysis of variance are uncorrected), they did appear to get a significant effect of smiling on heart rate recovery, with people forced to smile (aware or not) recovering from stress FASTER than those who weren't smiling. And it appears that in this case, bigger is better, with the Duchenne smiles having the biggest effect (and that one really is significant).
Here's the thing though. Holding chopsticks in your mouth is all fun and games, but, well, it's holding chopsticks in your mouth. Where's the non-chopstick condition, with people being instructed to smile without manual assistance? And, even more importantly, how did the participants FEEL about it? Did smiling make them rate the tasks as less arduous? More?
And of course there's the issue of the stats. Why uncorrected analysis of variance? And "marginally significant" at p=0.06? Man, my life would be SO much better if I was allowed to stop at marginal significance. And with n's as high as they got (around 58 people PER group), well...let's just say the effects were probably minor.
But still, there's nothing wrong with trying on a smile to try and fight the stress. And if you're particularly worried, you might try adding chopsticks! And then, whether or not it works for you, you'll at least amuse the people around you. They might be laughing AT you rather than WITH you, but hey...grin and bear it.
Kraft TL, & Pressman SD (2012). Grin and bear it: the influence of manipulated facial expression on the stress response. Psychological science, 23 (11), 1372-8 PMID: 23012270