November 21, 2011
Science Daily/Society for Research in Child Development
A nationwide Dutch study of 100 fourth graders sought to determine whether victimization and exclusion by peers were related to increases in cortisol (a stress hormone), and whether friendships moderated this association. The study found that children who were excluded by their classmates had elevated levels of cortisol at school, indicating that exclusion is stressful. Victimization by classmates wasn't associated with increased cortisol levels, suggesting that victimization is not as stressful as exclusion.
Children who were excluded by their classmates had elevated levels of cortisol at school, the study found. And they had a smaller decline in cortisol over the course of the day. Both of these findings may indicate that exclusion is stressful. This was even more pronounced for excluded kids who had few friends or had friendships that were characterized as low in quality.