Although research on the reasons for engaging in nonsuicidal self-injury (NSSI) has increased dramatically in the last few years, there are still many aspects of this pernicious behavior that are not well understood. The purpose of this study was to address these gaps in the literature, with a particular focus on investigating whether NSSI (a) regulates affective valence in addition to affective arousal and (b) serves a cognitive regulation function in addition to an affect regulation function. To elucidate these issues, the present study utilized a sample of 112 participants (33 controls, 39 no pain controls, 16 NSSI individuals, and 24 controls matching the affect dysregulation levels of the NSSI group), employed psychophysiological measures of affective valence (startle-alone reactivity) and quality of information processing (prepulse inhibition), and used experimental methods involving an NSSI-proxy to model the NSSI process. Results largely were consistent with predictions, supporting the hypotheses that NSSI serves to regulate cognitive processing and affective valence. On this latter point, however, the control groups also showed a decrease in negative affective valence after the NSSI-proxy. This unexpected finding is consistent with the hypothesis that opponent processes may contribute to the development of self-injurious behaviors (Joiner, 2005). Overall, the present study represents an important extension of previous laboratory NSSI studies and provides a fertile foundation for future studies aimed at understanding why people engage in NSSI.

Research suggests that adolescents' engagement in nonsuicidal self-injurious (NSSI) behaviors may be increasing over time, yet little is known regarding distal longitudinal factors that may promote engagement in these behaviors. Data from two longitudinal studies are presented to examine whether NSSI may be associated with peer influence processes. Study 1 included 377 adolescents from a community-based sample; Study 2 included 140 clinically-referred adolescents recruited from a psychiatric inpatient facility. In Study 1, adolescents' NSSI was examined at baseline and one year later. Adolescents' nominated best friend reported their own levels of NSSI. In Study 2, adolescents' NSSI was examined at baseline as well as 9 and 18-months post-baseline. Adolescents' perceptions of their friends' engagement in self-injurious behavior (including suicidality) and depressed mood also were examined at all three time points. Baseline depressive symptoms were measured in both studies; gender and age were examined as moderators of peer influence effects. Results from both studies supported longitudinal peer socialization effects of friends' self-injurious behavior on adolescents' own NSSI for girls, but not for boys, even after controlling for depressive symptoms as a predictor. Study 1 suggested socialization effects mostly for younger youth. Results from Study 2 also suggested longitudinal socialization effects, as well as peer selection effects; adolescents' NSSI was associated with increasing perceptions of their friends' engagement in depressive/self-injurious thoughts and behavior. Findings contribute to the nascent literature on longitudinal predictors of NSSI and to work on peer influence.

The emergence of a research literature exploring parallels between physical and nonphysical (i.e., social, relational, indirect) forms of aggression has raised many questions about the developmental effects of aggressive behavior on psychological functioning, peer relationships, and social status. Although both forms of aggression have been linked to problematic outcomes in childhood and adolescence, more recent findings have highlighted the importance of considering the possible social rewards conferred by socially aggressive behavior. This paper examines relevant theory and empirical research investigating the adaptive and maladaptive correlates specific to nonphysical forms of aggression. Findings are explored at the level of group (e.g., peer rejection), dyadic (e.g., friendship quality), and individual (e.g., depressive symptoms) variables. Key developmental considerations and methodological issues are addressed, and recommendations for future research integrating current theoretical conceptualizations and empirical findings on social aggression are advanced.

No abstract

Objective Little is known about the patterns among individuals in the long-term course of suicidal thoughts and behaviors (STBs). The objective of this study was to identify developmental trajectories of STBs from adolescence through young adulthood, as well as risk and protective covariates, and nonsuicidal outcomes associated with these trajectories. Method 180 adolescents (ages 12–18 at recruitment) were repeatedly assessed over an average of 13.6 years (2,273 assessments) since their psychiatric hospitalization. Trajectories were based on ratings of STBs at each assessment. Covariates included psychiatric risk factors (proportion of time in episodes of psychiatric disorders, hopelessness, trait anxiety, impulsivity, and aggression in adulthood, sexual and physical abuse, parental history of suicidal behavior), protective factors (survival and coping beliefs, social support in adulthood, parenthood), and nonsuicidal outcomes (social adjustment and functional impairment in adulthood, school drop-out, incarcerations). Results Using a Bayesian group-based trajectory model, four trajectories of STBs were identified: (1) an Increasing Risk class (11%), (2) a Highest Overall Risk class (12%), (3) a Decreasing Risk class (33%), and (4) a Low Risk class (44%). The four classes were associated with distinct patterns of correlates in risk and protective factors and nonsuicidal outcomes. Conclusion Adolescents and young adults have heterogeneous developmental trajectories of STBs. These trajectories and their covariates may inform strategies for predicting STBs and targeting interventions for individuals at risk for suicidal behavior.