Faking a smile does improve mood, study confirms

A man fakes a smile with his teeth and fingers close-up.

Even forcedly, the simple act of smiling can improve mood, establish work published in the journal Nature Human Behavior.

The idea that simply mimicking emotions can induce them is not new. Although a hundred studies have been published on the subject, their results so far did not clearly establish that facial expressions influence our emotional experience, a hypothesis known as facial feedback.

It is a very simple hypothesis which assumes that if we mime a facial expression on our face, then we will tend to feel this emotion, explains Pierrich Plusquellec, researcher at the Center for Studies in Science of the nonverbal communication (CESCNOV) affiliated with the University of Montreal, which did not participate in the work.

“For example, if I make an angry facial expression, after a few seconds I will feel angry. If I make a facial expression of joy, as tested in this article, then I will feel more joy. »

— Pierrich Plusquellec, researcher at CESCNOV

But the facial feedback hypothesis is not easy to prove since it is necessary to measure the emotion and ensure that people mimic expressions correctly.

• In 1978, psychologists Paul Ekman and Wallace Friesen developed a method for describing facial movements (facial action coding system) which became the main measurement tool used in studies focusing on to facial expression.
• In 1988, the social psychologist Fritz Strack published a study which tends to show the existence of the phenomenon of facial feedback. In his experiment, the researcher asks participants to rate how funny a cartoon series is by holding a pencil between their lips, which forces a frown; then between the teeth, which compels a smile. The results showed that those who smiled judged the cartoons funnier than those who frowned.
• As of 2016, experiments conducted in 17 laboratories failed to replicate the results obtained in 1988.
• In 2019, Stanford University researcher Nicholas Coles compiled fifty years of research and 138 studies in a meta-analysis that suggests changing facial expression can alter the emotions experienced.

Following his meta-analysis, the researcher Nicholas Coles decides to settle the question once and for all by bringing together within the same study, the Many Smiles project, researchers who support or oppose the facial feedback theory.

“It hardly ever happens that researchers with opposing ideas come together. We are rather entitled to steeple battles, and we will settle the question in congresses with sometimes very emotional discussions. »

— Pierrich Plusquellec, University of Montreal

Researchers have agreed on an experimental methodology with the objective of determining whether a person's subjective emotional experiences can be influenced by their facial expressions.

This is a solid study, very well done. One of the strengths of his research protocol is that it can be transposed from one culture to another, with participants from countries as varied as France and Japan, notes Pierrich Plusquellec.

The study was conducted among 3878 participants in 19 countries divided into three groups in which the three techniques used in previous studies were tested:

1) imitate facial expressions of actors appearing in photos;

2) move the corners of the mouth to the cheeks using only the facial muscles;

3) use the pen-in-the-mouth technique which involves moving the facial muscles to simulate a smile.

In each of the groups, half of the participants performed the task while looking at happy images of puppies, kittens, flowers, and fireworks, and the other half simply observed a blank screen. They also viewed these same types of images (or lack thereof) while exhibiting a neutral facial expression.

To mask the objective of the experiment and minimize On the bias, the researchers incorporated several other small physical tasks and asked the participants to solve simple mathematical problems. Then, after each task, participants rated how happy they felt.

There are two types of smiles:

• The true (involuntary) smile involves the zygomatic major muscles, which stretch obliquely from the cheekbone to the corner of the lips, and the orbicular muscles of the eye, which form an elliptical area around the eyelids and spread out in a thin layer over the eyelids themselves.
• The smile false or social (voluntary), in which only the zygomatic muscles are contracted.

Thus, the contraction of the muscles around the eyes would distinguish a smile reflecting a really positive emotion from a smile of circumstance.

The results obtained establish that the first two methods lead to a perceptible increase in happiness, which proves that human emotions are linked to muscle movements. The pen technique did not yield conclusive results, probably because it does not create an authentic expression that closely resembles a smile.

These results make a compelling argument in favor of a link between human emotions and muscle movements or other physical sensations.

The authors of the work believe that the effect observed with the first two techniques arises because facial expressions provide sensorimotor feedback to the brain that contributes to the perception of an emotion, a view shared by Pierrich Plusquellec.

Facial feedback exists, but its effects are weak. Nothing, however, to give hope of treating depression, says Pierrich Plusquellec, who nevertheless thinks that these results, obtained after 5-second facial feedback, open the door to other experiments.

“Now imagine if participants were asked to smile involuntarily or voluntarily multiple times for 5 seconds a day. If you were asked to do this 10 times in the morning, would that significantly increase your joy throughout the day? »

— Pierrich Plusquellec, University of Montreal

Pierrich Plusquellec points out that there are other types of feedback, such as that of power postures, described by Pre Amy Cuddy of Harvard University in 2010. His method, tested on his students, shows that when they adopt a strength posture two minutes before a stressful moment, their testosterone (the dominance hormone) level rose and cortisol (the stress hormone) level dropped. According to the researcher, body language influences how others perceive you, but also how you perceive yourself.

Two examples:

< li>stand tall, feet apart, hands on hips and chin tilted up;
• sit on a chair, back leaning against the backrest, legs crossed on the desk with hands behind the neck.

Work on power postures seems to follow a similar path to that on facial feedback. Other researchers were unable to replicate Amy Cuddy's findings in subsequent studies, but a meta-analysis published in 2020 appears to provide preliminary evidence of the effect of power posture on responses. affective and behavioral. A future study conducted with a methodology similar to that used by researcher Nicholas Coles could settle the question in the coming years.

For Pierrich Plusquellec, work carried out on facial or postural feedback tend to show that creating something with our body in a conscious way leads to a feeling of confidence.

“It allows us to feel what is related to that movement. I do, therefore I feel something. »

— Pierrich Plusquellec, University of Montreal

Pierrich Plusquellec believes that the results of the Many Smiles project will lead to the study of the link between social feedback and emotional contagion, the door to empathy.

“There is scientific consensus on the neurocognitive model of empathy, which states that when you face someone x27;one and that person smiles at you or has any facial expression, you will automatically mimic that facial expression, which is called motor empathy. This will create emotional contagion in you which will help you recognize the emotion. »

— Pierrich Plusquellec, University of Montreal

The present work will, according to him, create a consensus on the existence of facial feedback, one of the mechanisms of emotional contagion. We have just suddenly explained one of the reasons why we can be contaminated by the emotions of others, he believes.