November 20, 2024
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Forcing a smile using electrical stimulation can boost your mood
The researchers directed an electric current to activate facial muscles and then asked the study participants how they felt.
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The saying “a smile a day keeps the blue away” may have credence beyond the realm of greeting card messages. The perennial question of whether a smile or a frown elevates or depresses emotion has persisted for decades and is still debated.
In a new study, researchers looked for a more precise answer by using electrical muscle stimulation to force people to literally turn the corners of their mouths up or down by smiling or frowning. They found evidence of what appears to be a physical act of making these statements it directly affects human emotionsmake a person feel more positive or negative.
The idea that the body plays a role in shaping how people feel and perceive the world is “old and fascinating,” says Sebastian Korb, senior professor of psychology at the University of Essex in England and lead author of the published study. in the year the emotion. “But it’s not universally accepted.” Korb says the new research suggests that facial activity affects emotions and adds evidence to this long-standing but controversial hypothesis.
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The roles that facial expressions play in influencing human emotions in the 19th century. It has its roots in the 19th century, when Charles Darwin and the philosopher and psychologist William James postulated that physiological changes in the body can influence emotions. In the 20th century researchers began to look at the influence of facial expression, and in the 1970s this idea was formally described as the “facial feedback hypothesis”.
In the decades since, the hypothesis has received mixed empirical support. In 1988, German researchers published a study that has become public as a pen task. The participants were divided into two groups and asked to manipulate a pen with their mouth in different ways. Both groups drew the pen straight, perpendicular to the lips, but one group held the pen between the teeth, which facilitated the appearance of a smile, while the other group held the pen between the lips and closed their mouth, creating a kissing expression. The participants then found a series of cartoons to be humorous. Those whose mouths stretched into a smile found the cartoons funnier than those that resembled a kiss, which the researchers interpreted as evidence supporting the facial feedback hypothesis.
The well-known study was challenged, however, in 2016 by a group of researchers—including Korb.tried to replicate the findings Across 17 laboratories, each of which conducted a study with more than 100 participants. In contrast to the original study, the researchers’ results did not reveal significant evidence to support the facial feedback hypothesis.
“Some people said we should forget the hypothesis altogether,” says Korb, “others, like me, were like, ‘Wait a second, maybe we shouldn’t throw the baby out with the bath water.’ rather than putting it in your mouth.”
For the new study, Korb and his colleagues turned to electrical stimulation, a method that allowed them to target specific facial muscles for a specific amount of time. They placed electrodes on the skin of 58 participants and gradually increased the current until it caused a contraction that forced them to frown or smile. Anatomical variability between participants means that each received a slightly different level of current to activate the target muscle.
Each participant was subjected to various experimental conditions for five seconds: smiling or frowning while looking at a blank screen; smiling while looking at a happy picture, such as a beautiful beach; and frowning at a depressing image, such as a beach covered in trash. They also performed the same set of experiments with weaker stimulations that produced no visible movement of the participants’ facial muscles. After experiencing each condition, participants rated how positively or negatively they felt.
Across all measures, the researchers found correlations between participants’ facial features and how they said they felt, but no change in mood when exposed to weaker stimulation. The strongest correlation occurred when smiles were paired with positive images. However, in the absence of accompanying images, participants rated mood lower when their facial muscles were forced to frown and higher when they were encouraged to smile. For non-imaging findings, “the effect wasn’t dramatic,” says Korb. “But remember, we’re activating some muscles at a very small level for five seconds, so we’re already putting ourselves in a situation where it’s not obvious that we’d find an effect.”
Heather Lench, a professor of psychological and brain sciences at Texas A&M University who was not involved in the research, says the new research was well done and “opens up a whole new way of influencing facial expressions.”
Now that Korb and his colleagues have preliminary confirmation that the method works, they are planning additional studies, he says. Future research could investigate how activating different facial muscles makes people feel, or use electroencephalograms to determine how quickly the brain responds to these emotional changes. More work will also be needed, he added, to clarify the more difficult question, whether it is actually the activity of the facial muscles that affects emotions, or whether the study participants are aware that those muscles are being activated, which makes them think. corresponding emotion
Lench added that there may also be practical applications for Korb and his colleagues’ findings. “If there is a strong enough relationship between muscle activation and emotions, it opens up an interesting application of the work: that people can self-stimulate their muscles using wearable devices, for example, to change their emotional state,” he says. “The health, ethical and societal implications of this type of application are very interesting.”
