It turns out that this age-old trick to make oneself feel happier actually works

The idea that we can force emotions by expressing them is as old as psychology. It was supported, then debunked, and supported again (with warnings). Now, it may be necessary to admit that there is something to do "return this frown" after all.

With 138 studies on the effect of our facial expressions on our mood, researchers from the University of Tennessee and Texas A & M University have looked closely at the evidence and found a small but significant effect under certain circumstances.

"Conventional wisdom tells us that we can feel a little happier if we simply smile, or that we can get in a bad mood if we growl," says social psychologist Nicholas Coles of the University of Tennessee.

"But psychologists have disagreed on this idea for over 100 years."

Even the good old Charles Darwin had an opinion on the subject. "The free expression by the outward signs of an emotion intensifies it," writes the naturalist in his less famous book. The expression of emotions in humans and animals.

This "facial feedback hypothesis", as we have come to know, has been kicked regularly ever since. Various experiments have made it possible to verify whether the execution of a facial expression to obtain a change of mood would reverse the usual order, where the emotion was followed by a physical reaction.

One of the best-known examples in recent history is asking volunteers to evaluate cartoons while holding a pen in the mouth and pushing their lips in a rather awkward smile.

The results suggested that even a tense grin could be enough for people to feel like laughing, sparking a new generation of discounted bins filled with guides on how to laugh for a better life.

Nearly thirty years later, a famous 1988 experiment sparked controversy when a coordinated replication study conducted by the original researchers and using more than 1,800 participants spread across 17 labs. nothing revealed.

For those who are tired of being told to smile because it will make you feel better, the result has been nice.

"But we can not focus on the results of a particular study," said Coles. "Psychologists have been testing this idea since the early 1970s, so we wanted to look at all the evidence."

Such psychological experiences can be notoriously difficult, with all kinds of variables that can skew the results. There are various badumptions of facial feedback and a range of disagreements about their effects.

Coles and his colleagues, Jeff Larsen, and psychologist Heather Lench of Texas A & M University conducted a statistical meta-badysis to explore the diversity of methods to dispel some common prejudices and see if there were more.

The effect was not really huge. But it was there, suggesting that we can feel a little smarter while smiling, or experience a degree of disgust if we sneer. On the other hand, playing the emotions of fear or surprise will not do you much.

They also found that these effects were different for some evocative stimuli, such as cartoons versus sentences. Forcing yourself to smile while watching a Garfield comic book will not make it funny, no matter how big that smile is.

The research will undoubtedly keep the field of research on facial feedback alive for a moment. The cause-and-effect relationship between our mood and the reactions of our body is undoubtedly a complicated relationship that will require serious work to solve it.

"We still have a lot to learn about these facial feedback effects, but this meta-badysis brings us a little closer to understanding how emotions work," said Coles.

The researchers made it clear that they did not think it meant we could just smile at our depression.

Nevertheless, we will probably need to endure being told a little longer by well-intentioned life coaches. Just try to smile and bear it.

This research was published in Psychological Bulletin.