The coming of winter means cooler temperatures, shorter days and flu shots. While no one looks forward to a vaccination, a study led by the University of California, Irvine, has found that either a sincere smile or a grimace can reduce the pain of a needle injection by as much as 40 percent. A genuine, or Duchenne, smile—one that elevates the corners of the mouth and creates crow’s feet around the eyes—can also significantly blunt the stressful, needle-related physiological response by lowering the heart rate.
“When facing distress or pleasure, humans make remarkably similar facial expressions that involve activation of the eye muscles, lifting of the cheeks and baring of the teeth,” said principal investigator Sarah Pressman, UCI professor of psychological science. “We found that these movements, as opposed to a neutral expression, are beneficial in reducing discomfort and stress.”