Entering "self-injury" as a search term in Google yields over 15 million results. Using the same term to search YouTube brings up 2,140 videos (1). Self-injury appears in popular movies, music lyrics, and music videos. It is described in books, the news, and on the Internet. Ask any adolescent today what self-injury is, and not only will he or she likely be able to define it, nearly half asked will personally know someone who has engaged in the behavior. Self-injury has become such a part of the social landscape today there are even jokes about it: "I wish my grass were Emo so it would cut itself." How are these two phenomena, presence of self-injury in the media and widespread knowledge of it in adolescent populations, related?
Non-suicidal self-injury (NSSI) is defined as the deliberate, self-inflicted destruction of body tissue without suicidal intent and for purposes not socially sanctioned (International Society for the Study of Self-Injury, 2007). Notably common in adolescent and young adult populations (e.g., ages 13-24), studies have found that between 14% and 23% have engaged in NSSI at some point in their lives (e.g., Muehlenkamp & Gutierrez, 2007; Ross & Heath 2002; Whitlock, Eckenrode, & Silverman, 2006) and studies of mental health providers consistently find broad agreement that prevalence has increased over time (Heath, Toste, & Beettam, 2006; Purington, Whitlock, & Pochtar, 2009; Whitlock, Eells, Cummings, & Purington, 2009). With such widespread use of NSSI amongst youth, awareness of NSSI across mental health providers, and large numbers of today's youth reporting they personally know at least one person who has self-injured (i.e., 41% of all respondents in a large 8 college sample; Whitlock, 2009), some have gone so far as to call NSSI the "next teen disorder" (Welsh, 2004). Whether this characterization would garner widespread agreement or not, one thing is clear: self-injury is now a common feature of the adolescent and young adult social landscape. What is less clear is this: what makes NSSI, often used as a maladaptive coping method (Klonsky, 2007; Nock, 2009), so common now?
The answer may be what epidemiologists call "social contagion." Like bacteria that result in disease, behaviors and attitudes are transmissible. The acceptance and adoption of certain behaviors can be communicable and passed from one person to another through vehicles not always recognized for this capacity.
Evidence of contagion has been clearly documented in the adoption of fashion trends (Gladwell, 2000), disordered eating (Crandall, 1988), smoking cessation (Christakis & Fowler, 2008), and even suicide (Phillips, 1974). If NSSI is increasing in prevalence, it is highly likely that contagion is at work in the spread of NSSI as well. But just how do ideas and behaviors, like NSSI, spread? While peer-to-peer interactions are certainly influential, their effects are likely to be restricted to small, relatively isolated groups. Moreover, this level of influence does not explain how NSSI could have spread so far and wide over a fairly short period of time. To understand this, the remainder of this article first...
This is a preview. Get the full text through your school or public library.