A new study conducted by researchers at the National Institute of Mental Health (NIMH) and Georgia State University looked at psychiatrically healthy Americans ages 9 to 17 to determine what happens in the brains of preteens and teens at a time of significant change in social behavior.

The youths looked at photos of peers and rated their interest in interacting with each one. Then they underwent a brain scan while reviewing the pictures and rated how much each young person in the picture might want to interact with them in return. The youths were told they would be matched with a peer for a chat after the scan.

The study was conducted among mostly White psychiatrically healthy Americans and found that in older girls (as compared to younger girls), brain regions (the nucleus accumbens, insula, hypothalamus, hippocampus, and amygdala) associated with social rewards and motivation, processing emotions, hormonal changes, and social memory responded differently when they thought about being judged by their peers, especially peers with whom they wanted to interact. These differences were not evident between younger and older boys.

"The findings offer a fresh perspective on how changes in the brain relate to changes in the way young people think and feel about how their peers view them," according to Amanda E. Guyer, a research fellow at NIMH, who led the study. "They are relevant for parents, teachers, and clinicians who are trying to help teens adjust socially during adolescence. They may be especially relevant for girls, who are more likely than boys to feel anxious and depressed at this time."

The research was supported by NIMH and appears in the July/August 2009 issue of the journal Child Development.