Botox may smooth your wrinkles, but it can dull your ability to understand the emotions of others, a new study suggests.
Botox, used in cosmetic and medical procedures for 20 years, paralyzes muscles, hindering certain facial movements, such as frowns, that over time can cause wrinkles.
Therein lies the problem, says David Neal, a psychology professor at the University of Southern California, lead author of the research, published today in the journal Social Psychology and PersonalityScience.
"People who use Botox are less able to read others' emotions," says Neal, who worked with a researcher at Duke University in Durham, N.C.
People read emotions partly by mimicking facial expressions, Neal says, so "if muscular signals from the face to the brain are dampened, you're less able to read emotions."
Researchers conducted two experiments, one of 31 women, comparing Botox with Restylane, a dermal filler, and the other of 56 women and 39 men, using a gel that amplifies muscular signals. Participants in both experiments viewed computer images of faces and identified the emotions they saw.
"When the facial muscles are dampened, you get worse in emotion perception, and when the facial muscles are amplified, you get better at emotion perception," Neal says.
A similar study published last year in the journal Emotion said Botox injections may decrease a person's ability to feel emotions. That study, conducted at Columbia University, compared Botox and Restylane in 68 people. Its lead author, psychologist Joshua Davis, hasn't seen the new study but says the finding "would suggest that facial expression is an integral component of what we consider our emotional experience. Certainly the concept is one that fits with the research we did."
Dermatologist Elizabeth Tanzi of Washington says she's treated at least 10 patients a day with Botox for a decade and has never heard a complaint related to emotions.
"It's important that facial expression is there," she says. "People care about what they look like, but they do not want to look overly done or overly plasticized."
Neal says users should "consider whether these procedures are having any indirect costs — reducing their ability to empathize and understand people's emotions."