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Background: Orbitofrontal cortex (OFC) dysfunction has been proposed to increase the risk for developing a substance use disorder (SUD) during adolescence. In this study, we suggest that a reduction in OFC volumes might underlie temperament-based risk factors for SUD, and examined whether smaller OFC volumes during early adolescence could predict later development of SUD. Methods and Materials: Adolescents (n = 107; 58 male, 49 female) underwent structural MRI and completed a self-report measure of temperamental effortful control at age 12. At 3 subsequent assessments (aged 15, 16, and 18) SUD was assessed via a semi-structured clinical interview. By the third assessment, 24 participants (22.4%) had received a lifetime diagnosis of SUD. Results: Smaller volumes of the left OFC, right OFC, and left medial subregions predicted lifetime history of SUD by age 18. Volumes of the left OFC and left lateral subregions were positively correlated with effortful control, and left OFC volumes mediated the relationship between effortful control and SUD. Conclusions: Smaller volumes of the OFC and low effortful control during adolescence appear to be associated phenotypes that increase the risk of subsequent SUD. Further studies examining the temporal sequence of these risk factors are needed to fully understand this relationship.

AbstractEarly to mid‐adolescence is an important developmental period for subcortical brain maturation, but longitudinal studies of these neurodevelopmental changes are lacking. The present study acquired repeated magnetic resonance images from 60 adolescent subjects (28 female) at ages 12.5 and 16.5 years to map changes in subcortical structure volumes. Automated segmentation techniques optimized for longitudinal measurement were used to delineate volumes of the caudate, putamen, nucleus accumbens, pallidum, hippocampus, thalamus and the whole brain. Amygdala volumes were described using manual tracing methods. The results revealed heterogeneous maturation across the regions of interest (ROIs), and change was differentially moderated by sex and hemisphere. The caudate, thalamus and putamen declined in volume, more for females relative to males, and decreases in the putamen and thalamus were greater in the left hemisphere. The pallidum increased in size, but more so in the left hemisphere. While the left nucleus accumbens increased in size, the right accumbens decreased in size over the follow‐up period. Increases in hippocampal volume were greater in the right hemisphere. While amygdala volume did not change over time, the left hemisphere was consistently larger than the right. These results suggest that subcortical brain development from early to middle adolescence is characterized by striking hemispheric specialization and sexual dimorphisms, and provide a framework for interpreting normal and abnormal changes in cognition, affect and behavior. Moreover, the differences in findings compared to previous cross‐sectional research emphasize the importance of within‐subject assessment of brain development during adolescence.

AbstractMeta‐emotion philosophy refers to an organized set of thoughts, reactions, and feelings about one's emotions and the emotions of others (Gottman, Katz, & Hooven, 1997). This study investigated the prospective relationship between family meta‐emotion processes and adolescent‐onset major depressive disorder (MDD). Adolescents (N = 198, mean age 12.5 years) and one of their parents each completed the Meta‐Emotion Interview (Katz & Gottman, 1986), and adolescents were followed‐up at ages 15, 16.5, and 19 years to assess for MDD onset. In the Meta‐Emotion Interviews, parents and adolescents were asked about both their own, and the others', anger and sadness. Results showed that parent‐report of their own meta‐emotion philosophy of sadness prospectively predicted MDD onset in adolescence, as did adolescent‐report of low parental emotion coaching in relation to sadness, and adolescent self‐perceived emotional competence in relation to sadness. Adolescents' perceptions of family emotional environments characterized by high levels of parental anger expression and family conflict also prospectively predicted MDD onset. These findings highlight the continued importance of family emotional processes in adolescence, and provide insight into how parents' and adolescents' perceptions of emotional processes within the family, particularly in relation to sadness, may be prospectively associated with risk for adolescent onset MDD.