Developmental perspectives on vulnerability to nonsuicidal self-injury in youth.

Nonsuicidal self-injury (NSSI) is defined as intentionally causing bodily harm to oneself without the intent to kill oneself. Recently, there has been an increase in research aimed at understanding why individuals, especially youth and young adults, engage in NSSI. This chapter explores the emergence and maintenance of NSSI from a developmental perspective. Epidemiological research suggests that rates of NSSI increase dramatically from early adolescence to young adulthood. No study has investigated NSSI in youth younger than age 10. Current understanding of how emotion and cognitions as well as interpersonal processes play a role in the emergence and maintenance of NSSI is explored. Further, the role of biology (e.g., neurological underpinnings, genetic associations, HPA-axis functioning) on NSSI is explored. Throughout the chapter, particular limitations (e.g., sample selection, measurement issues) in the extant corpus of knowledge are highlighted. Finally, we consider future research directions that may inform developmentally sensitive understanding of the proximal and distal risk factors that may affect the emergence and maintenance of NSSI across the life span.