Self-injuring adolescent girls exhibit insular cortex volumetric abnormalities that are similar to those seen in adults with borderline personality disorder.

Self-inflicted injury (SII) in adolescence is a serious public health concern that portends prospective vulnerability to internalizing and externalizing psychopathology, borderline personality development, suicide attempts, and suicide. To date, however, our understanding of neurobiological vulnerabilities to SII is limited. Behaviorally, affect dysregulation is common among those who self-injure. This suggests ineffective cortical modulation of emotion, as observed among adults with borderline personality disorder. In borderline samples, structural and functional abnormalities are observed in several frontal regions that subserve emotion regulation (e.g., anterior cingulate, insula, dorsolateral prefrontal cortex). However, no volumetric analyses of cortical brain regions have been conducted among self-injuring adolescents. We used voxel-based morphometry to compare cortical gray matter volumes between self-injuring adolescent girls, ages 13-19 years (n = 20), and controls (n = 20). Whole-brain analyses revealed reduced gray matter volumes among self-injurers in the insular cortex bilaterally, and in the right inferior frontal gyrus, an adjacent neural structure also implicated in emotion and self-regulation. Insular and inferior frontal gyrus gray matter volumes correlated inversely with self-reported emotion dysregulation, over-and-above effects of psychopathology. Findings are consistent with an emotion dysregulation construal of SII, and indicate structural abnormalities in some but not all cortical brain regions implicated in borderline personality disorder among adults.

Forms of non-suicidal self-injury as a function of trait aggression.

To date, the considerable body of research on predictors of non-suicidal self-injury (NSSI) has conceptualized NSSI as a unitary construct despite the fact that NSSI can exist in many forms (e.g., hitting, cutting, burning). The goal of the present study is to examine differential prediction of forms of NSSI. Specifically, we examined trait aggression as a predictor of more aggressive forms of NSSI (i.e., hitting). We hypothesized that higher trait aggression would differentiate those who engaged in hitting forms of NSSI from those who did not, whereas other factors (i.e., emotion regulation and trait anger) would serve as a non-specific predictor of NSSI. We also hypothesized that higher trait aggression would be related to lifetime frequency of hitting NSSI, but not other forms of NSSI, whereas emotion regulation and anger would act as predictors of other forms of NSSI. To test these hypotheses, a large sample of young adults completed measures of trait aggression, trait anger, emotion regulation, and NSSI behaviors. Results were generally in line with our hypotheses. Higher levels of trait aggression differentiated those who engaged in hitting NSSI from those who did not and was also associated with greater frequency of hitting NSSI. These results imply that different factors predict different forms of NSSI and that NSSI may be best examined as a multi-faceted construct.

The Relationship Between Nonsuicidal Self-Injury Age of Onset and Severity of Self-Harm.

This study examined how age of nonsuicidal self-injury (NSSI) onset relates to NSSI severity and suicidality using decision tree analyses (nonparametric regression models that recursively partition predictor variables to create groupings). Those with an earlier age of NSSI onset reported greater NSSI frequency, NSSI methods, and NSSI-related hospital visits. No significant splits were found for suicide ideation or attempts, although those with an earlier onset were more likely to have a suicide plan. Overall, findings suggest that onset of NSSI before age 12 is associated with more severe NSSI and may be a crucial age for prevention efforts.

Negative urgency and reward/punishment sensitivity in intermittent explosive disorder.

UNLABELLED: Intermittent explosive disorder (IED) is the sole psychiatric diagnosis in which affective aggression is the cardinal symptom. Previous research has been equivocal with regard to the relationship between IED and impulsivity. This inconsistency may reflect the varied facets of impulsivity, with some aspects of impulsivity (e.g. negative urgency) as well as some overlapping, albeit distinct constructs (e.g. reward and punishment sensitivity) yet to be studied. METHODS: The present study compared individuals diagnosed with IED (n=81) with psychiatric controls (PCs; n=52) and healthy volunteers (HVs; n=58) on the impulsivity domains of negative and positive urgency, perseverance, sensation seeking, and premeditation, as well as on reward and punishment sensitivity. We hypothesized that individuals with IED would show greater negative and positive urgency, reward sensitivity, punishment sensitivity, with negative urgency independently predicting IED status. We also hypothesized that negative urgency would predict levels of anger, aggression, and aggression control among those with IED. RESULTS: The IED participants reported greater negative urgency than both comparison groups, and greater levels of positive urgency, reward sensitivity, and punishment sensitivity compared to HVs. Further, heightened negative urgency was the sole predictor an IED diagnosis. Within the IED group negative urgency uniquely predicted decreased aggression control and increased trait anger. LIMITATIONS: Limitations included reliance on self-report measures to assess RS/PS, impulsivity, and aggression. CONCLUSIONS: These findings suggest that negative urgency is a key factor associated with IED and is associated with dampened control of aggression within those with IED.