How Treating Wrinkles May Also Relieve Depression Juan Silva / Getty Images Mature woman receiving injection to her forehead It's a popular cosmetic treatment but early data hints that Botox could have a role in treating not just aging, but mental illness as well. And the connection may actually be skin deep. Data now suggests that treating frown lines and erasing the outward signs of aging may actually lift spirits among people with depression. As odd (and superficial) as it sounds, the connection actually derives from a significant body of research. The idea that physical expressions of emotion influence our experience of feelings goes back to Charles Darwin, who studied emotions in both animals and humans in various cultures. Darwin referred to the frown muscles as the "grief muscles," and connected frowns to feelings of sadness. MORE: The Internet Knows You're Depressed, But Can It Help You? "We feel sorry because we cry; we feel angry because we strike [out] and not vice versa," Dr. Eric Finzi, medical director of the Chevy Chase Cosmetic Center in Maryland, said as he presented the latest study on Botox's influence on depression at the annual meeting of the American College of Neuropsychopharmacology in December. Although later research has showed that the connection runs both ways - you can feel sorry and then cry or the other way around - physically expressing an emotion does seem to be important trigger for feelings. For example, forcing a frown can launch a depressed mood while deliberately smiling can elevate it, at least temporarily (hence the research showing that people who laugh or smile regularly can improve their mood). Studies have also shown that people find jokes funnier when they place a pencil between their teeth lengthwise, which forces a smile, than when they hold it pointing outwards, which doesn't. MORE: How Childhood Trauma May Make the Brain Vulnerable to Addiction, Depression The new study is the second to compare Botox to placebo, although the results have not yet been thoroughly reviewed enough for publication in a scientific journal. Two prior open label studies and one small controlled trial, however, suggest that it holds promise. The 84 study participants had severe depression that lasted on average for two years and had failed to completely respond to antidepressant medication. The patients were randomized to receive either Botox treatment for smoothing out frown lines or a placebo injection into the same facial region, and were assessed three and six weeks later. By the end of the study, around 27% of those receiving Botox reported nearly complete remission of their depression, compared to just 7% of those who received placebo. "[This trial shows] that inhibition of frowning can lead to remission in depression," Finzi said. MORE: Should Depressed People Avoid Having Children? While the data showed a trend that suggested greater remission was linked with a larger reduction in visible frowning, "an observable frown at rest was not necessary to see improvement," he said. Of course, it's possible that Botox may be affecting depression in a more biological way, such as through the immune system, which can be altered during depression. But Finzi said that other studies with larger Botox doses have not found significant systemic effects, leading him to believe its primary benefit may be in helping people to see themselves as "happier." Because there has been so little research, however, it's too soon to suggest that Botox could be the next Prozac. But the results suggest an intriguing mind-body connection that could open up new ways to alleviate the symptoms of depression. MORE: America's Failing Mental Health System: Families Struggle to Find Quality Care