By Peter M. Vishton, PhD, William & Mary

Edited by Kate Findley and proofread by Angela Shoemaker, The Great Courses Daily

Studies have found that smiling actually leads to happiness. Where does plastic surgery—specifically, Botox—fit into this equation? Professor Vishton examines the evidence.

How Botox Affects Emotions

The facial feedback hypothesis suggests that how you use your face dictates your mood—for example, if you smile, you will start feeling happy. If this hypothesis is correct, then something that plastic surgeons do every day affects the emotions and emotional expression of many of their patients: Botox injections. 

It’s become a routine procedure for medical professionals to inject botulinum toxin into the skin of patients, with the goal of producing smoother, less wrinkled skin. The botulinum toxin—Botox—achieves this by paralyzing the muscles that squeeze and stretch the face.

Many people receive Botox injections to reduce frown lines—wrinkles that often appear beyond the edges of the mouth associated with the downward movements we make with our mouths. Once a patient has these injections, they partially lose the ability to frown. 

If you survey those people a few weeks later, they ironically don’t tend to rate themselves as looking more attractive, but they do report feeling happier—or at least, less sad. If the face loses its ability to make sad expressions, it seems that our tendency to feel sad feelings may be reduced.

This particular Botox study fits the narrative, but some details are less than compelling. Maybe people just feel better in general once they’ve received a treatment aimed at improving their appearance. 

Maybe that’s what produced the observed reduction in sadness and/or the increase in happiness. Other studies, however, suggest that that’s not the case.

MRI Botox Study

“In one of my favorite studies on this topic, participants who had received facial Botox injections were placed in a functional magnetic resonance imaging scanner—an fMRI,” Professor Vishton said.

This type of scanner senses the pattern of blood flow in the brain, and can thus determine when different parts of the brain become especially active or inactive. If you look at pictures of faces and mimic those expressions, the emotion processing centers of the brain will light up. 

That’s been well-established in the past. If you compare Botox patients, however, they produce significantly less activity in those emotional centers than do typical participants.

This result is different from those found in other studies on facial feedback hypothesis in some important ways. These studies have examined how your own facial expressions affect your own mood. Here, it seems that how you process the emotional states of the people around you is also affected by what you do—and don’t do—with your face.

In a related study, experimenters asked people to read short text passages and judge their emotional content. Participants who’d received general Botox treatments were slower at this task than standard control participants.

Evidence for Facial Feedback Hypothesis

In a sense, this is the best type of evidence for facial feedback hypothesis. The theory rests on the premise that the very nature of your emotional reasoning—the emotion processing that takes place in your brain—is based on things that you do with your body, specifically with your face. 

Here, people aren’t explicitly making or perceiving facial expressions at all. They are reading words and judging the emotional content.

According to Professor Vishton, research on the cognitive neuroscience of emotions indicates that you should avoid Botox injections—or anything else that might affect the ability of your face to express emotions. However, if one feels they are too emotional or too strongly influenced by the emotions of others, then Botox might be a possible treatment to reduce that effect. 

Regardless of your decision, be aware that your face is important for lots of reasons that don’t have to do with your personal appearance.

When you feel or express an emotion or process the emotional states of others around you, a lot of information processing takes place. Certainly, some of that computation takes place in the emotion centers of your brain. Some important parts of it take place in the muscles of your face, though.

These studies suggest a new set of ideas about the relationship between our brains and the rest of our bodies. Much of modern science has often thought of the brain as a standalone, information-processing device—like the king of the body that makes unilateral calculations and hands down orders to be carried out. Many cognitive neuroscientists have adopted an alternative approach, centered around the notion of embodied cognition.

The basic idea is that many of the impressive feats that we credit to our cerebrum are actually accomplished by a complex interaction between the brain and the rest of the body. Certainly in terms of emotional processing that seems to be the case. What you do with your body—and your face in particular—plays an important role in how you feel.

This article was edited by Kate Findley, Writer for The Great Courses Daily, and proofread by Angela Shoemaker, Proofreader and Copy Editor for The Great Courses Daily.

Peter M. Vishton is Associate Professor of Psychology at William & Mary. He earned his PhD in Psychology and Cognitive Science from Cornell University. Before joining the faculty of William & Mary, he taught at Northwestern University and served as the program director for developmental and learning sciences at the National Science Foundation.