There are millions of botulinum toxin (botox) treatments performed, mostly on women, around the world every year. And this sort of cosmetic intervention may have side effects — ones that go beyond the merely cosmetic.
In the Pixar movie Inside Out, the emotions are represented as little people living inside of us. To feel an emotion, according to this fantasy, is for one or another of these inner characters, now anger, now sadness, for example, to take center stage in our mental theaters. (I discussed Inside Out here when it came out.)
The intuitive idea that emotions are inside us, and that they cause our bodies to give vent to them in different ways, has been subject to scientific scrutiny and criticism for more than a century. William James, for example, proposed that it is a mistake to think of emotions as occurring in you, and of their physical and physiological expression as being merely bodily effects. Part of what it is to feel happy, James argued, is to experience your bodily smile. Famously, according to James, the fear that I feel when confronted with the bear is not the cause of my flight response; it is my flight response — or at least part of it. The fear is, in part, an experience of my body's reaction to the threatening creature.
James's theory actually makes a lot of intuitive sense. "Put on a brave face." "Keep a stiff upper lip." "Turn that frown upside down." This is folk wisdom and it speaks to the thought that if you do it, you will feel it.
Which brings us back to botox. One of the main applications of botulinum toxin is to paralyze (temporarily) corrugator muscles between the eyes; this has the effect of relaxing glabellar frown lines, or in other words, of soothing the furrowed brow.
If James is right, if the tension in the face is the emotion and not merely an effect of it, then treating the tension lines in the face may be a way of getting rid of unwanted negative feeling and restoring positive emotion.
So maybe those millions of woman are on to something. Cosmetic surgery isn't just skin deep after all. Or rather, our emotional lives are, in a way, skin deep as well. Emotions are on our bodies.
In fact, the possibility that botox treatments can enhance positive emotion and even be used to treat depression is one that has been researched closely, and, it seems, with some success, in the last few years. Even patients showing no cosmetic benefit from treatments, report mood improvement after treatment.
But where there are effects, there are side-effects — and these, too, are just beginning to come into focus. It is widely suspected that our ability to perceive and understand the emotional states of other people is tied to our spontaneous and usually unconscious tendency to imitate. I understand what you are feeling by acting it out myself, however partially, however implicitly. If this is right, then it stands to reason that it would be harder for me to discern your mood, as it finds itself expressed on your face, if I am myself unable, for what ever reason, to perform the same expressive dance of my own facial muscles.
This is exactly what new research on the effects of temporary botox paralysis supports: After getting botox injections, patients were somewhat impaired, as compared with people who had received no injections, in their ability to detect very slight emotional expressions in other people (as measured, for example, by the speed with which they could categorize pictures of faces as happy or sad, or by their ability to rate the emotional intensity and valence of face pictures and even sentences).
The bottom line of the research: Botox treatments blunt the sensitivity of otherwise healthy people to the emotions of others. And it does so, presumably, because the botox has the effect of impairing the ability to move the muscles in your face in the way you see them being moved by the other.
Sample sizes were small in this study; only 11 Italian-speaking woman aged 35 to 66. But the potential significance of the finding is striking. As the authors J.-C. Baumeister,, G. Papam and F. Foroni, working in Trieste, Italy, write, "a blunting towards [slightly emotional] stimuli may have important consequences for interpersonal communication and everyday life."
Emotion may be skin deep, after all. And perceiving emotion may depend as much on the quality of one's own skin as it does on one's eyesight.
Alva Noë is a philosopher at the University of California, Berkeley, where he writes and teaches about perception, consciousness and art. He is the author of several books, including his latest, Strange Tools: Art and Human Nature (Farrar Straus and Giroux, 2015). You can keep up with more of what Alva is thinking on Facebook and on Twitter: @alvanoe