Nearly one in five adolescents has engaged in non-suicidal self-injury, and those adolescents with friends who engage in self-harm are at higher risk for the behavior.
But adolescent social networks are complex.
New research from Northeastern University shows this complexity — finding that having a greater number of friends can protect against non-suicidal self-injury among friends, while also being a greater risk factor for adolescents who are in multiple social groups.
“It’s a very complex data analysis,” says Jiaao Yu, a Ph.D. student in sociology at Northeastern who studies the formation of social relationships and how they impact behavior and mental health.
Non-suicidal self-injury (NSSI) is defined as harming one’s own body without suicidal intent. Common examples include cutting, burning, scratching and banging or hitting; and most people who engage in the behavior have used multiple methods.
Yu explains that researchers generally study the topic from one of two perspectives: social contagion (the spread of attitudes or behaviors) and social integration (the process by which groups and individuals come together).
The social contagion aspect of the research focuses on why adolescents who have friends involved in NSSI are more likely to engage in NSSI themselves, whether they see it as normal behavior for coping with distress or as a way to fit in or signal membership in a group.
The social integration (or social position) research, on the other hand, focuses on connections across a broader peer network — including friends, friends of friends and beyond — whether they engage in NSSI.
“Social contagion is more intimate, the direct connection between one person and his or her friends,” Yu explains. “Social integration is more of how you connect to a broader peer group and how you are embedded within a peer group.”
For the latest study, published in the Journal of Youth and Adolescence, Yu wanted to combine these perspectives.
So, using data from 9,581 Chinese schoolchildren across 221 classrooms and including early adolescents (ages 9-13) and middle-to-late adolescents (ages 14-20), Yu examined whether children who act as bridges — meaning they have friends among multiple peer groups — were more likely than children with friends in one social group to engage in NSSI.
He found that, although there is an association between friends’ NSSI and an individual’s self-harm, the more friends one has in their social group, the weaker this association becomes.
“So, it is important to have more social connections,” Yu says.
“Bridges” with more than five friends among many social groups and in early adolescence, however, are more likely to engage in self-harm.
“It may be that it’s more challenging to balance the demands of multiple peer groups,” Yu said. “I think this is especially likely for early adolescents, who are less secure in their problem-solving abilities.”
Yu says he next wants to try a similar analysis of social position as it relates to other adolescent behaviors such as bullying, or outcomes such as delinquency.
“Mapping relationships creates a dynamic picture of where and through whom risk travels,” Yu says. “And it points us to the most effective places to intervene.”