Longitudinal examination of marijuana use and physical teen dating violence: Antisocial peers and impulsivity as mediators.

BACKGROUND: Prior studies have shown that marijuana use is often associated with physical teen dating violence. However, few studies have examined the longitudinal mediating effects of associating with antisocial peers and impulsivity on this relationship. Also, few studies have estimated the cascading developmental impact of marijuana use and antisocial peer association, predicting the continued marijuana use and antisocial peer associations while considering the risk of impulsivity in physical teen dating violence. Thus, the current study utilized the problem behavior theory and an alternative path to physical dating violence to address these limitations. OBJECTIVE: The current study tested the longitudinal effects of marijuana use on physical teen dating violence and the indirect effects of antisocial peer association and impulsivity on this relationship (M = 12.29); 52.1 % of males and 47.9 % of females participated. METHODS: Adolescents completed questionnaires at baseline and were assessed six months later (n = 836). Generalized structural equation modeling (GSEM) and cross-lagged mediation models were used first to analyze the direct effect of lifetime marijuana use on physical dating violence and antisocial peer association and impulsivity as potential mediators of this relationship. Then, the cross-lagged mediation models were used to estimate the alternative path to physical teen dating violence using lifetime marijuana use and antisocial peer association as predictors at baseline and continued antisocial peer association, marijuana use, and impulsivity at the subsequent wave as mediators. RESULTS: Results suggested that marijuana use at baseline was not positively associated with physical teen dating violence over time. The association with antisocial peers but not impulsivity mediated the relationship between marijuana use and physical dating violence. Cross-lagged mediation results suggested that marijuana use at baseline positively predicted antisocial peer association in the subsequent wave, which led to an increase in physical teen dating violence. Further, antisocial peer association at baseline is positively associated with continued antisocial peer association at the subsequent wave; thus, antisocial peer association is positively related to physical teen dating violence when controlling for depressive symptoms, family support, number of dates, and parental monitoring. CONCLUSION: These results suggest though marijuana use alone is not statistically associated with physical teen dating violence, it does increase the risk of antisocial social peer associations that could increase adolescents' likelihood to engage in physical teen dating violence. Further, the onset of antisocial peer association could persist over time, thus serving as a risk factor for physical teen dating violence over time.

Neurodiversity and Intelligence: Evaluating the Flynn Effect in Children with Autism Spectrum Disorder.

The Flynn Effect (FE) among child and adolescent populations indicates that intelligence scores improve by about three points per decade. Using nine years of data from the National Database for Autism Research, this study examined whether general intelligence changed significantly for nine cohorts with autism spectrum disorder (ASD; N = 671). Analyses demonstrated a downward trend such that Cohen's d from 1998 to 2006 was - 0.27. The mean IQ is 92.74 for years 1-3, 91.54 for years 4-6, and 87.34 for years 7-9, indicating a reverse FE of 5.4 points per decade. A linear regression revealed a significant negative FE comparable to the positive effect of age on IQ among those with ASD. Implications for research, practice, and law are discussed.