I love it when I learn something new that adds a bit of joy to life. In the book Blink by Malcolm Gladwell, I read of a study done by three men – Paul Ekman, Wallace Friesen and Robert Levenson, on what happens in the body as a result of facial expressions.
Volunteers were “…hooked up to monitors measuring their heart rate and body temperature – the physiological signals of such emotions as anger, sadness, and fear. Half the volunteers were told to try to remember and relive a particularly stressful experience. The other half were simply shown how to create, on their faces, the expressions that corresponded to stressful emotions, such as anger, sadness, and fear. The second group, the people who were acting, showed the same physiological responses, the same heightened heart rate and body temperature, as the first group.” (p. 207)