Characterizing heterogeneity in early adolescent reward networks and individualized associations with behavioral and clinical outcomes

AbstractAssociations between connectivity networks and behavioral outcomes such as depression are typically examined by comparing average networks between known groups. However, neural heterogeneity within groups may limit the ability to make inferences at the individual level as qualitatively distinct processes across individuals may be obscured in group averages. This study characterizes the heterogeneity of effective connectivity reward networks among 103 early adolescents and examines associations between individualized features and multiple behavioral and clinical outcomes. To characterize network heterogeneity, we used extended unified structural equation modeling to identify effective connectivity networks for each individual and an aggregate network. We found that an aggregate reward network was a poor representation of individuals, with most individual-level networks sharing less than 50% of the group-level network paths. We then used Group Iterative Multiple Model Estimation to identify a group-level network, subgroups of individuals with similar networks, and individual-level networks. We identified three subgroups that appear to reflect differences in network maturity, but this solution had modest validity. Finally, we found numerous associations between individual-specific connectivity features and behavioral reward functioning and risk for substance use disorders. We suggest that accounting for heterogeneity is necessary to use connectivity networks for inferences precise to the individual

Adolescent Developmental Trajectories of Self-Reported Reward Responsiveness and Inhibitory Control and the Role of Clinical and Neural Predictors

Understanding the adolescent development of reward responsiveness and inhibitory control, as well as predictors of this development, is important due to associations with key outcomes such as depression and substance use disorders. However, relatively few studies have examined this development longitudinally, and past findings have been mixed, particularly for self-reported development of reward responsiveness. Here, we examined the longitudinal development of self-reported reward responsiveness and inhibitory control in a sample of over 200 adolescents aged 9-17 across 5 waves. We also examined associations between several clinical and neural measures as predictors of longitudinal trajectories. We found that inhibitory control increased across adolescence. However, contrary to hypotheses and common models of adolescent development, we found that self-reported reward responsiveness decreased across adolescence. These results suggest that within-person changes of experiences of reward responsiveness may not correspond with developmental assumptions built on studies of neural responses to reward. We also found that heightened centrality of a cognitive control functional connectivity hub during a reward task was associated with increased social anhedonia and greater decreases in reward responsiveness trajectories, suggesting a potential risk factor warranting further study. Overall, results conflict with traditional models of adolescent development and highlight the need for increased longitudinal study of subjective experience of reward responsiveness

Examining the Neurobiology of Non-Suicidal Self-Injury in Children and Adolescents: The Role of Reward Responsivity

Although prior work has shown heightened response to negative outcomes and reduced response to positive outcomes in youth with a history of non-suicidal self-injury (NSSI), little is known about the neural processes underlying these responses. Thus, this study examined associations between NSSI engagement and functional activation in specific regions of interest (ROIs) and whole-brain connectivity between striatal, frontal, and limbic region seeds during monetary and social reward tasks. To test for specificity of the influence of NSSI, analyses were conducted with and without depressive symptoms as a covariate. We found that NSSI was associated with decreased activation following monetary gains in all ROIs, even after controlling for depressive symptoms. Exploratory connectivity analyses found that NSSI was associated with differential connectivity between regions including the DS, vmPFC, insula, and parietal operculum cortex when controlling for depressive symptoms. Disrupted connectivity between these regions could suggest altered inhibitory control of emotions and pain processing in individuals with NSSI. Findings suggest dysfunctional reward processes in youth with NSSI, even very early in the course of the behavior

Specificity of Brain Volume Alterations in Children with Various Parental Histories of Psychopathology

Background: Multiple forms of parental psychopathology have been associated with differences in child subcortical brain volume. Much of this work has relied on studies of individual forms of parental psychopathology without considering the role of comorbid disorders. Here, we examine the specificity of relationships between multiple forms of parental psychopathology and alterations in child subcortical brain structure. Method: We examined 6581 children from the ABCD study with no history of mental disorders. Hierarchical linear models were used to examine whether neuroanatomical correlates of parental history of depression, anxiety, mania, and alcohol/substance use are disorder-specific or general across different disorders, and whether interactions between parental disorders were associated with offspring brain structure. Results: There were several significant interactions such that the effects of parental histories of depression, anxiety, and substance use problems on the volume of the amygdala and striatal regions were moderated by comorbid parental history of another disorder. Additionally, a parental history of depression was associated with smaller amygdala volume and a parental history of mania was associated with larger amygdala, pallidum, thalamus, and total subcortical volume before and after controlling for histories of other parental disorders. Conclusion: Results suggest that effects of a parental history of various forms of psychopathology on offspring subcortical brain volume are moderated by comorbid history of other disorders, highlighting the importance of assessing multiple forms of psychopathology when examining neurobiological associations. A limitation is that measures of parental psychopathology did not come from gold standard interview assessments and lacked information of timing, duration, and severity

Highly emissive layers based on organic/inorganic nanohybrids using Aggregation Induced Emission effect

International audienceFluorescent nanohybrids, based on p-extended hydroxyoxophosphole ligands grafted onto ZnO nanoparticles, were designed and studied. The restriction of the intramolecular motions of the organic fluorophore, through either aggregates' formation in solution or processing into thin films, forms highly emissive materials due to a strong Aggregation Induced Emission effect. Theoretical calculations and XPS analyses were performed to analyze the interactions between the organic and inorganic counterparts. Preliminary results on the use of these nanohybrids as solution-processed emissive layers in Organic Light Emitting Diodes (OLEDs) illustrate their potential for lighting applications