Botox injections may not just limit facial expressions, but they may also decrease a person’s ability to feel emotions.
Many people undergo Botox injections to paralyze facial muscles in order to decrease the appearance of wrinkles, but new findings show that by limiting facial expressions, they may also be limiting their ability to feel emotions.
“With Botox, a person can respond otherwise normally to an emotional event, e.g. a sad movie scene, but will have less movement in the facial muscles that have been injected, and therefore less feedback to the brain about such facial expressivity,” said Dr. Joshua Davis of Barnard College, who led the study with colleague Dr. Ann Senghas.
It has been thought for years that facial expressions influence emotions, for example, that smiling can make you happier, and frowning can make you sadder, but research has never before been able confirm the theory.
“With the advent of Botox, it is now possible to work with people who have a temporary, reversible paralysis in muscles that are involved in facial expression,” said Davis. “The muscle paralysis allows us to isolate the effects of facial expression and the subsequent sensory feedback to the brain that would follow from other factors, such as intentions relating to one’s expression and motor commands to make an expression.”
Davis and Senghas enrolled two groups of participants into their study. One group underwent Botox injections, and the control group had Restylane injections. Restylane injections are also used in cosmetic surgery to decrease the appearance of wrinkles, but Restylane works as a filler, not by paralyzing the muscle.
The group who underwent the Botox injections were shown both positively and negatively emotionally charged video clips before and after the injections, and asked to rate their emotional responses. After the injections, the participants were still able to respond emotionally to the most positive and negative emotional clips.
However, compared to the control group, the Botox participants “exhibited an overall significant decrease in the strength of emotional experience.”
The greatest difference was seen in the Botox group’s diminished ability to respond to the mildly positive video clips.
Davis and Senghas’s findings confirm the long-suspected belief that facial expressions, while not a necessary element, do in fact contribute to real emotions. While this diminished emotional response is believed to be temporary, patients planning to undergo such cosmetic procedures may need to consider this factor in their decision process.
Further research can help to clarify the relationship between facial expression and emotion, and may help to determine if some patients are at higher risk for emotional consequences from Botox injections.
Dr. Davis’s research is published in the June issue of the journal Emotion.