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Background: Neuroimaging studies on adolescents at risk for depression have relied on a single risk factor and focused on adolescents in high‐income countries. Using a composite risk score, this study aims to examine neural activity and connectivity associated with risk and presence of depression in adolescents in Brazil. Methods: Depression risk was defined with the Identifying Depression Early in Adolescence Risk Score (IDEA‐RS), calculated using a prognostic model that included 11 socio‐demographic risk factors. Adolescents recruited from schools in Porto Alegre were classified into a low‐risk (i.e., low IDEA‐RS and no lifetime depression), high‐risk (i.e., high IDEA‐RS and no lifetime depression), or clinically depressed group (i.e., high IDEA‐RS and depression diagnosis). One hundred fifty adolescents underwent a functional MRI scan while completing a reward‐related gambling and a threat‐related face‐matching task. We compared group differences in activity and connectivity of the ventral striatum (VS) and amygdala during the gambling and face‐matching tasks, respectively, and group differences in whole‐brain neural activity. Results: Although there was no group difference in reward‐related VS or threat‐related amygdala activity, the depressed group showed elevated VS activity to punishment relative to high‐risk adolescents. The whole‐brain analysis found reduced reward‐related activity in the lateral prefrontal cortex of patients and high‐risk adolescents compared with low‐risk adolescents. Compared with low‐risk adolescents, high‐risk and depressed adolescents showed reduced threat‐related left amygdala connectivity with thalamus, superior temporal gyrus, inferior parietal gyrus, precentral gyrus, and supplementary motor area. Conclusions: We identified neural correlates associated with risk and presence of depression in a well‐characterized sample of adolescents. These findings enhance knowledge of the neurobiological underpinnings of risk and presence of depression in Brazil. Future longitudinal studies are needed to examine whether the observed neural patterns of high‐risk adolescents predict the development of depression. [ABSTRACT FROM AUTHOR]

Background: Childhood maltreatment is one of the most potent predictors of future psychopathology, including internalizing disorders. It remains unclear whether heightened amygdala reactivity to threat and elevated stress exposure may be implicated in the pathogenesis and maintenance of internalizing disorders among individuals with a history of childhood maltreatment. Methods: Using data from a sample of 1,144 young adults, we investigated the contribution of baseline threat‐related amygdala reactivity and prospective major stressful life events to internalizing symptoms severity 1 year later (on average) in individuals with a history of maltreatment (n = 100) and propensity score matched nonmaltreated peers (n = 96). Results: Even after stringently matching for several potentially confounding variables – including baseline internalizing symptoms, socioeconomic status and IQ – childhood maltreatment status predicted increased amygdala reactivity at baseline, elevated post‐baseline exposure to major stressful life events and internalizing symptoms at follow‐up. We also showed, for the first time, that amygdala reactivity at baseline and also post‐baseline exposure to major stressful life events mediated the association between a history of maltreatment and future internalizing symptoms. Conclusions: These findings provide support for the view that maltreatment is a potent developmental insult leading to long‐lasting neurocognitive recalibrations of the threat processing system. It is possible that such alterations, over time, may impact mental health functioning by compromising the ability to effectively negotiate everyday challenges (stress susceptibility). These alterations were not, however, found to sensitize an individual to the impact of major stressful life events. The results of this study also lend compelling support to the view that increased psychiatric risk, in the context of childhood maltreatment, follows from an increased propensity to experience major stressful life events (stress generation). [ABSTRACT FROM AUTHOR]

Autism spectrum disorders (ASD) involve a core deficit in social functioning and impairments in the ability to recognize face emotions. In an emotional faces task designed to constrain group differences in attention, the present study used functional MRI to characterize activation in the amygdala, ventral prefrontal cortex (vPFC), and striatum, three structures involved in socio-emotional processing in adolescents with ASD. Twenty-two adolescents with ASD and 20 healthy adolescents viewed facial expressions (happy, fearful, sad and neutral) that were briefly presented (250 ms) during functional MRI acquisition. To monitor attention, subjects pressed a button to identify the gender of each face. The ASD group showed greater activation to the faces relative to the control group in the amygdala, vPFC and striatum. Follow-up analyses indicated that the ASD relative to control group showed greater activation in the amygdala, vPFC and striatum ( p < .05 small volume corrected), particularly to sad faces. Moreover, in the ASD group, there was a negative correlation between developmental variables (age and pubertal status) and mean activation from the whole bilateral amygdala; younger adolescents showed greater activation than older adolescents. There were no group differences in accuracy or reaction time in the gender identification task. When group differences in attention to facial expressions were limited, adolescents with ASD showed greater activation in structures involved in socio-emotional processing. [ABSTRACT FROM AUTHOR]