Deadly gun violence, neighborhood collective efficacy, and adolescent neurobehavioral outcomes

Heterogeneous Effects of Environmental Exposure to Gun Violence on Adolescent Problem Behavior

Mounting evidence suggests that gun violence occurring within a community can affect community members even when they do not experience it firsthand. Building on this expanded view of exposure, the present study examined the effects of environmental exposure to gun violence-that is, living or attending school within 1,300 m of a past-year firearm homicide occurrence-on adolescents' problem behaviors (delinquent, externalizing, and internalizing behaviors) using data from the Future of Families and Child Wellbeing Study merged with information on firearm homicide incidents from the Gun Violence Archive (N = 3,086; girls: N = 1,504; Black/white/Latinx/other: N = 525/1,547/773/241). Employing propensity score matching methods, we estimated the average effects of environmental gun violence exposure on adolescents' problem behaviors and assessed heterogeneity in these effects across subgroups of youth with different exposure probabilities (low, moderate, and high). While average effects were not observed, environmental gun violence exposure was associated with increased delinquent (but not externalizing) behavior among adolescents, particularly girls, with low risk of exposure and decreased internalizing behavior among adolescents with low and moderate risk of exposure. These findings highlight the importance of investigating the differential impacts of gun violence exposure across subgroups with varying pre-exposure risks. Adolescents at relatively low risk of exposure may benefit from supportive services to address behavior problems in the aftermath of gun violence; though, resources for adolescents with elevated pre-exposure risks remain vital for redressing broader inequities that contribute to gun violence in the first place.

Early childhood family threat and longitudinal amygdala-mPFC circuit development: Examining cortical thickness and gray matter-white matter contrast

Early threat-associated cortical thinning may be interpreted as accelerated cortical development. However, non-adaptive processes may show similar macrostructural changes. Examining cortical thickness (CT) together with grey/white-matter contrast (GWC), a proxy for intracortical myelination, may enhance the interpretation of CT findings. In this prospective study, we examined associations between early life family-related threat (harsh parenting, family conflict, and neighborhood safety) and CT and GWC development from late childhood to middle adolescence. MRI was acquired from 4200 children (2069 boys) from the Generation R study at ages 8, 10 and 14 years (in total 6114 scans), of whom 1697 children had >1 scans. Linear mixed effect models were used to examine family factor-by-age interactions on amygdala volume, caudal and rostral anterior cingulate (ACC) and medial orbitofrontal cortex (mOFC) CT and GWC. A neighborhood safety-by-age-interaction was found for rostral ACC GWC, suggesting less developmental change in children from unsafe neighborhoods. Moreover, after more stringent correction for motion, family conflict was associated with greater developmental change in CT but less developmental change in GWC. Results suggest that early threat may blunt ACC GWC development. Our results, therefore, do not provide evidence for accelerated threat-associated structural development of the amygdala-mPFC circuit between ages 8-14 years.

Assessing the acute effects of exposure to community violence among adolescents: A strategic comparison approach

This paper examines whether exposure to spatially proximate homicide affects norms, attitudes, and the adaptive strategies adolescents take to insulate themselves from violent victimization. Drawing on survey data from a large sample of urban youth (n = 3195), we assess the impact of homicides occurring within a one-mile radius of respondents' homes on a variety of psychosocial outcomes. We exploit random variation in the timing of survey administration to compare the survey responses of youths who were exposed to a homicide in the immediate vicinity of their homes in the one-month period leading up the administration of the survey with students who did not experience a homicide near their homes during that period but would the following month. This strategic comparison approach minimizes the confounding influence of endogenous processes that funnel children and families into places where homicides tend to concentrate.

Exposure to community violence as a mechanism linking neighborhood disadvantage to amygdala reactivity and the protective role of parental nurturance

Emerging literature links neighborhood disadvantage to altered neural function in regions supporting socioemotional and threat processing. Few studies, however, have examined the proximal mechanisms through which neighborhood disadvantage is associated with neural functioning. In a sample of 7- to 19-year-old twins recruited from disadvantaged neighborhoods (354 families, 708 twins; 54.5% boys; 78.5% White, 13.0% Black, 8.5% other racial/ethnic group membership), we found that exposure to community violence was related to increased amygdala reactivity during socioemotional processing and may be one mechanism linking neighborhood disadvantage to amygdala functioning. Importantly, parenting behavior appeared to modulate these effects, such that high parental nurturance buffered the effect of exposure to community violence on amygdala reactivity. These findings elucidate the potential impact of exposure to community violence on brain function and highlight the role parents can play in protecting youth from the neural effects of exposure to adversity. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Building towards an adolescent neural urbanome: Expanding environmental measures using linked external data (LED) in the ABCD study

Many recent studies have demonstrated that environmental contexts, both social and physical, have an important impact on child and adolescent neural and behavioral development. The adoption of geospatial methods, such as in the Adolescent Brain Cognitive Development (ABCD) Study, has facilitated the exploration of many environmental contexts surrounding participants' residential locations without creating additional burdens for research participants (i.e., youth and families) in neuroscience studies. However, as the number of linked databases increases, developing a framework that considers the various domains related to child and adolescent environments external to their home becomes crucial. Such a framework needs to identify structural contextual factors that may yield inequalities in children's built and natural environments; these differences may, in turn, result in downstream negative effects on children from historically minoritized groups. In this paper, we develop such a framework - which we describe as the "adolescent neural urbanome" - and use it to categorize newly geocoded information incorporated into the ABCD Study by the Linked External Data (LED) Environment & Policy Working Group. We also highlight important relationships between the linked measures and describe possible applications of the Adolescent Neural Urbanome. Finally, we provide a number of recommendations and considerations regarding the responsible use and communication of these data, highlighting the potential harm to historically minoritized groups through their misuse.

Neighborhood collective efficacy and environmental exposure to firearm homicide among a national sample of adolescents

BACKGROUND

Living near an incident of firearm violence can negatively impact youth, regardless of whether the violence is experienced firsthand. Inequities in household and neighborhood resources may affect the prevalence and consequences of exposure across racial/ethnic groups.

FINDINGS

Using data from the Future of Families and Child Wellbeing Study and the Gun Violence Archive, we estimate that approximately 1 in 4 adolescents in large US cities lived within 800 m (0.5 miles) of a past-year firearm homicide during 2014-17. Exposure risk decreased as household income and neighborhood collective efficacy increased, though stark racial/ethnic inequities remained. Across racial/ethnic groups, adolescents in poor households in moderate or high collective efficacy neighborhoods had a similar risk of past-year firearm homicide exposure as middle-to-high income adolescents in low collective efficacy neighborhoods.

CONCLUSIONS

Empowering communities to build and leverage social ties may be as impactful for reducing firearm violence exposure as income supports. Comprehensive violence prevention efforts should include systems-level strategies that jointly strengthen family and community resources.

Adolescent neurodevelopment and psychopathology: The interplay between adversity exposure and genetic risk for accelerated brain ageing

In adulthood, stress exposure and genetic risk heighten psychological vulnerability by accelerating neurobiological senescence. To investigate whether molecular and brain network maturation processes play a similar role in adolescence, we analysed genetic, as well as longitudinal task neuroimaging (inhibitory control, incentive processing) and early life adversity (i.e., material deprivation, violence) data from the Adolescent Brain and Cognitive Development study (N = 980, age range: 9-13 years). Genetic risk was estimated separately for Major Depressive Disorder (MDD) and Alzheimer's Disease (AD), two pathologies linked to stress exposure and allegedly sharing a causal connection (MDD-to-AD). Adversity and genetic risk for MDD/AD jointly predicted functional network segregation patterns suggestive of accelerated (GABA-linked) visual/attentional, but delayed (dopamine [D2]/glutamate [GLU5R]-linked) somatomotor/association system development. A positive relationship between brain maturation and psychopathology emerged only among the less vulnerable adolescents, thereby implying that normatively maladaptive neurodevelopmental alterations could foster adjustment among the more exposed and genetically more stress susceptible youths. Transcriptomic analyses suggested that sensitivity to stress may underpin the joint neurodevelopmental effect of adversity and genetic risk for MDD/AD, in line with the proposed role of negative emotionality as a precursor to AD, likely to account for the alleged causal impact of MDD on dementia onset.

Heterogeneous effects of spatially proximate firearm homicide exposure on anxiety and depression symptoms among U.S. youth

The burden of firearm homicide in the United States is not evenly distributed across the population; rather, it disproportionately affects youth in disadvantaged and marginalized communities. Research is limited relevant to the impacts of exposure to firearm violence that occurs near where youth live or attend school - spatially proximate firearm violence - on youths' mental health and whether those impacts vary by characteristics that shape youths' risk for experiencing that exposure in the first place. Using a dataset linking the Fragile Families and Child Wellbeing Study with the Gun Violence Archive (N = 3086), we employed propensity score matching and multilevel stratification to examine average and heterogeneous associations between spatially proximate firearm homicide exposure and anxiety and depression among all youth and then separately for boys and girls. We found a statistically significant average association between firearm homicide exposure and symptoms of depression among youth. Furthermore, heterogeneous effects analyses yielded evidence that the average association is driven by youth, and particularly boys, who are the most disadvantaged and have the highest risk of firearm homicide exposure. The results of this study suggest that the accumulation of stressors associated with structural disadvantage and neighborhood disorder, coupled with exposure to spatially proximate and deadly firearm violence, may make boys and young men, particularly Black boys and young men, uniquely vulnerable to the mental health impacts of such exposure. Ancillary analyses of potential effect moderators suggest possible future areas of investigation.

Neighborhood influences on the development of self-regulation among children of color living in historically disinvested neighborhoods: Moderators and mediating mechanisms

We present a conceptual model of the ways in which built and social environments shape the development of self-regulation in early childhood. Importantly, in centering children of color growing up in historically disinvested neighborhoods, we first describe how systemic structures of racism and social stratification have shaped neighborhood built and social environment features. We then present evidence linking these neighborhood features to children's development of self-regulation. Furthermore, we take a multilevel approach to examining three potential pathways linking neighborhood contexts to self-regulation: school environment and resources, home environment and resources, and child health behaviors. Finally, we consider how racial-ethnic-cultural strengths and multilevel interventions have the potential to buffer children's development of self-regulation in disinvested neighborhood contexts. Advancing multilevel approaches to understand the development of self-regulation among children of color living in historically disinvested neighborhoods is an important step in efforts to promote equity in health and education.