Many mental health conditions begin to emerge in adolescence. Some conditions, such as depression and anxiety, are much more common in adolescent females than males. For me, OCD emerged before any full-blown depression, although I did get very depressed during my OCD episodes. As the OCD improved, so would the depression. It wasn't until college that I was walloped with out-and-out depression completely separate from OCD.

But a recent study looking at how adolescents process emotions and social interaction shows how these features change during adolescence and how they can make a person vulnerable to anxiety and depression. The study asked a group of healthy adolescents between the ages of 9 and 17 to view a series of photos and determine both who they would be most interested in speaking with and who would be most interested in speaking with them. While they were evaluating the last question (who would be most interested in speaking with them), the teens' brains were scanned using functional Magnetic Resonance Imaging (fMRI).

During this evaluation, the fMRI scans found that older female adolescents showed greater activation in areas that processed social emotion, such as "the nucleus accumbens (reward and motivation), hypothalamus (hormonal activation), hippocampus (social memory) and insula (visceral/subjective feelings)." Very little shift in activity was found in younger vs. older male adolescents.

Lead researcher Daniel Pine, of the National Institutes of Mental Health, said this:

"In females, absence of activation in areas associated with mood and anxiety disorders, such as the amygdala, suggests that emotional responses to peers may be driven more by a brain network related to approach than to one related to fear and withdrawal," said Pine. "This reflects resilience to psychosocial stress among healthy female adolescents during this vulnerable period."

And it was this last quote that really stuck with me and made me think not just in terms of EDs, but in terms of ED vulnerabilities. Although I don't have social anxiety disorder, I do have social anxiety. Back in February, I had to go to a large science conference for work, and part of my task involved networking. My supervisor also went, and this is a man who loves to schmooze. He thrives on this kind of social interaction. I would just as soon volunteer to have a new dentist fix my messed-up teeth sans Novocain. I made my appearance, did my duty, and then got the hell out of there. I retreated back to my hotel room and read a book. When I have to mingle, I feel very anxious, very fearful, and more than just a little threatened. I'm edgy. I can't relax. I'm constantly evaluating how people respond to me and what they must be thinking and the second I can leave, I usually do.

So when Pine said that emotional responses in people with anxiety and depression are related to "fear and withdrawal," I realized how true this was. I'm guessing that I'm not the only person with an ED to respond this way to social interactions. This isn't true for all social interactions, but for many of them, especially where I might be "evaluated" by my peers. And maybe a transfer of activity from the more functional emotional circuitry (the nucleus accumbens, the insula, etc) to the amygdala is part of what drives not only the emergence of depression and anxiety, but also when these illnesses occur.