The acute effects of community violence on young children's regulatory, behavioral, and developmental outcomes in a low-income urban sample in Brazil

Effects of homicide timing on test scores: Quasi-experimental evidence from two cities in Colombia

This study examines the effect of homicides around schools on the standardized test scores of fifth and ninth graders (N = 4729; Mage = 12.71 years, SDage = 2.13) using a quasi-experimental design in two Colombian cities. Exposure to homicides occurring within 7 days of the test and within 500 m of the school decreases test scores by 0.10 SD. Effects show a greater sensitivity to timing than distance, becoming null as the time to the testing date increases but remaining consistent across larger radii. Since students in the study are on average exposed to 12.1 homicides per year, even short-lived learning losses can accumulate to impair learning for substantial portions of the school year. Findings are discussed, considering previous empirical work.

It takes a safe village to raise a child-a commentary on Dana McCoy et al. (2023)

This commentary on the study by McCoy et al. (2023) examining the negative effects of neighborhood violence on the development of toddlers growing up in the city of São Paulo (Brazil) interprets these outcomes from the perspective of ecological system theory, modern brain research, and the prospect of resilience. We argue that societies should give children the opportunity to grow up in a safe and sufficiently affluent social environment in order to give them a chance to achieve their full developmental potential. Governments and the health care system should, therefore, first and foremost invest in safe and stimulating child-rearing environments, informed by scientific research.

Community violence and early childhood language development: The moderating role of maternal efficacy and satisfaction

This paper estimates the acute effect of community-level homicides on early childhood language development and explores the moderating role of maternal efficacy and satisfaction in Chile. It uses data from the 2017 wave of the Early Childhood Longitudinal Survey of Chilean Children (N = 1194, Mage: 52.8 months, 52% girls). Children in municipalities with homicides 1 month before the Peabody Picture Vocabulary assessment scored between 0.18 and 0.41 SDs lower compared to children in the same municipality but for whom homicides happened after the assessment. On average, higher maternal satisfaction appears to have a protective effect, though it dissipates in the most violent municipalities. Evidence that higher maternal efficacy protects children from the negative effects of violence is inconclusive.

Unique and shared risk factors for early childhood victimisation and polyvictimisation in a Brazilian population-based birth cohort

Background

Identifying modifiable risk factors for child victimisation and polyvictimisation (exposure to multiple types of victimisation) is critical for informing prevention efforts, yet little evidence is available in low- and middle-income countries. The authors aimed to estimate the prevalence of child victimisation and polyvictimisation, and examine unique and shared risk factors in a population-based cohort in Southern Brazil.

Methods

Lifetime child victimisation was based on maternal report when children were aged 4 years old (N∼3900) and included five types of victimisation (conventional crime, child maltreatment, peer/sibling victimisation, sexual victimisation, and witnessing/indirect victimisation) and polyvictimisation. Based on a socioecological model, possible risk factors were examined in four levels: community, maternal and family, parent, and child.

Findings

Conventional crime and peer/sibling victimisation were the most common types of victimisation (46.0 and 46.5%, respectively), followed by witnessing/indirect victimisation (27.0%), and child maltreatment (11.3%). Sexual victimisation had the lowest prevalence (1.4%). One in 10 (10.1%) children experienced polyvictimisation. In general, boys had higher victimisation rates than girls. There were few risk factors related only to specific types of victimisation (e.g., child disability was uniquely associated with child maltreatment and peer/sibling victimisation). Instead, most risk factors were shared across nearly all victimisation types and also associated with polyvictimisation. These shared risk factors were: violent neighbourhood and low social cohesion, maternal adverse childhood experiences, younger maternal age, parental antisocial behaviour, intimate partner violence against mothers, and maternal depression.

Interpretation

These findings reveal a general pattern of accumulative risk effects for different types of victimisation and polyvictimisation, rather than unique risk profiles in children aged four year Prevention efforts should target risk factors at multiple levels (e.g.,: community, maternal and family and parent) during early childhood.

Funding

Wellcome Trust grant 10735_Z_18_Z.

Multilayer network associations between the exposome and childhood brain development

Growing up in a high poverty neighborhood is associated with elevated risk for academic challenges and health problems. Here, we take a data-driven approach to exploring how measures of children's environments relate to the development of their brain structure and function in a community sample of children between the ages of 4 and 10 years. We constructed exposomes including measures of family socioeconomic status, children's exposure to adversity, and geocoded measures of neighborhood socioeconomic status, crime, and environmental toxins. We connected the exposome to two structural measures (cortical thickness and surface area, n = 170) and two functional measures (participation coefficient and clustering coefficient, n = 130). We found dense connections within exposome and brain layers and sparse connections between exposome and brain layers. Lower family income was associated with thinner visual cortex, consistent with the theory that accelerated development is detectable in early-developing regions. Greater neighborhood incidence of high blood lead levels was associated with greater segregation of the default mode network, consistent with evidence that toxins are deposited into the brain along the midline. Our study demonstrates the utility of multilayer network analysis to bridge environmental and neural explanatory levels to better understand the complexity of child development.