Researchers now believe that facial expressions may influence emotional experiences, meaning people who are unable to make facial expressions to show emotions may also have a limited ability to feel these emotions.
"With Botox, a person can respond otherwise normally to an emotional event, [such as] 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," according to researcher Joshua Davis, a psychologist at Barnard College in New York.
Botox Emotion Study
The Barnard researchers showed study participants emotionally charged videos before and after they were injected with either Botox or Restylane -- which is a filler used to plump lips or facial wrinkles but does not limit facial movement. The Restylane group was used as a control group.
While Restylane appeared to have no effect on emotions, the Botox participants "exhibited an overall significant decrease in the strength of emotional experience," the researchers wrote in the study. Mildly positive clips in particular had a lower effect on Botox patients after they received the injections, the study noted.
Researchers believe the results stem from the fact that the mere act of smiling, for example, can help make a person happy, while frowning can bring them down, LiveScience reported.