A few weeks ago, a friend of mine was telling me about some of the trials and tribulations she was dealing with in raising her teenaged daughter. She realized that because the tension between the two of them had grown so great, she found herself scowling whenever her daughter walked into the room. Not surprisingly, her daughter responded to her mom's angry face with anger of her own.  

Fortunately, my friend realized what was happening, and while I can't say that altering her scowl completely fixed their relationship, she did say that it made a huge difference when she made an effort to project a relaxed, happy image to her daughter. More often than not, her daughter responded with her own relaxed smiles, and the lines of communication were kept open rather than slamming shut at first glance.

This story popped into my mind this morning after reading this piece on NPR that highlighted new research about how much we are are affected by the faces of those around us. The study, published in a recent issue of Psychological Science, found that people with aggression tend to see aggression in the faces of others around them — even those folks who might really be making happy or otherwise ambiguous faces. The problem is that it becomes a self-fulfilling prophecy when a hostile person sees an otherwise ambiguous person and mistakes their expression for aggression. The hostile person then responds aggressively, which causes the people around them to be aggressive, even if they didn't begin that way.

Dizzying, isn't it?

To further understand this relationship, and how to break the cycle, the authors of the study attempted to retrain participants — in this case, teens in a troubled youth program — who had problems with aggression. To start, the kids were asked to look at images of faces on a computer and label them as "happy" or "angry." Some of the faces were clearly happy while others were others clearly angry, but most were somewhere in the middle. This set point determined how each participant responded to the faces around them.

For the next phase of the study, researchers broke the kids into two groups and continued asking them to identify faces as "happy" or "angry" on the computer. But this time, kids in one half of the study group were given feedback about whether the person in the photo was actually happy or angry. After two weeks, researchers found that the kids who had been trained to see differently interacted with the world in a different way: They were less aggressive. According to the study, there was a 30 percent difference in aggression between the two groups.

So, could teens be happier and less aggressive if they were exposed to more happy faces? It's certainly worth a smile to find out.

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