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In a quest to learn what leads some people to turn to Facebook to connect with others, doctoral student Russell Clayton of the Missouri School of Journalism found that anxiety and alcohol use seem to play a big role.

For his master's thesis, which appears in the May issue of Computers in Human Behavior, Clayton surveyed more than 225 college freshman about two emotions, anxiety and loneliness, and two behaviors, alcohol and marijuana use. He found that the students who reported both higher levels of anxiety and greater alcohol use also appeared the most emotionally connected with Facebook. Those who reported higher levels of loneliness, on the other hand, said they used Facebook to connect with others but were not emotionally connected to it.

It probably isn't terribly surprising that those who are anxious may feel more emotionally connected to a virtual social setting than a public one, which Clayton acknowledges in a school news release. "Also, when people who are emotionally connected to Facebook view pictures and statuses of their Facebook friends using alcohol, they are more motivated to engage in similar online behaviors in order to fit in socially."

Marijuana use, on the other hand, predicted the opposite -- the absence of emotional connectedness to the site. Clayton has a theory about this as well: "Marijuana use is less normative, meaning fewer people post on Facebook about using it. In turn, people who engage in marijuana use are less likely to be emotionally attached to Facebook."

Whether Facebook is therapeutic for those feeling anxious is debatable. Last year one study found that people who use social networking sites regularly saw their behaviors change negatively, and that included having trouble disconnecting and relaxing. So the question becomes: Which came first, the anxiety or the networking?

Meanwhile, Facebook appears to be showing its laughter lines as teenagers "meh" their way to Twitter and Instagram. Surveys of their levels of anxiety and drug use while on those sites are surely imminent.