Parents, neighborhoods, and the developing brain

The ecology of poverty and children's brain development: A systematic review and quantitative meta-analysis of brain imaging studies

A growing number of studies have demonstrated associations between poverty and brain structure and function. However, the strength of this association and the effects of poverty level (e.g., family or neighborhood poverty), age and sex on the association are strikingly inconsistent across studies. We aimed to synthesize findings on gray matter volume and task-based brain activation associated with poverty in youth samples and disentangle the effects of poverty level, age, and sex. In general, poverty was associated with alterations in volume and activation in the frontal, temporal, and subcortical regions. Among 14,188 participants and 14,057 participants, poverty was associated with smaller gray matter volumes in the amygdala and hippocampus, respectively. Moderator testing revealed that family poverty had a stronger association than neighborhood poverty and that poverty was related to slower development of amygdala volume. Among 2696 participants, convergent functional alterations associated with poverty were observed in the left middle temporal gyrus (MTG) and left middle frontal gyrus across all task domains, with the percentage of girls positively associated with increased activation in the precuneus. Subgroup analyses revealed that greater poverty was associated with deactivation in the left MTG for top-down control and hyperactivity in the right superior temporal gyrus, left superior frontal gyrus, left insula, cerebellum/left fusiform gyrus, and left amygdala/hippocampus for bottom-up processing. These findings provide insights into the neuroscience of poverty, suggesting implications for targeted interventions to support the cognitive and mental health of children living in poverty.

Toward a multi-level approach to the study of the intergenerational transmission of trauma: Current findings and future directions

A central goal in the field of developmental psychopathology is to evaluate the complex, dynamic transactions occurring among biological, psychological, and broader social-cultural contexts that predict adaptive and maladaptive outcomes across ontogeny. Here, I briefly review research on the effects of a history of childhood maltreatment on parental, child, and dyadic functioning, along with more recent studies on the intergenerational transmission of trauma. Because the experience and sequelae of child maltreatment and the intergenerational transmission of trauma are embedded in complex biopsychosocial contexts, this research is best conceptualized in a developmental psychopathology framework. Moreover, there is a pressing need for investigators in this area of study to adopt dynamic, multi-level perspectives as well as using developmentally guided, sophisticated research methods. Other directions for research in this field are suggested, including the implementation of collaborative interdisciplinary team science approaches, as well as community-based participatory research, to increase representation, inclusion, and equity of community stakeholders. A greater focus on cultural and global perspectives is also recommended.

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.

Developmental Timing of Associations Among Parenting, Brain Architecture, and Mental Health

Importance

Parenting is associated with brain development and long-term health outcomes, although whether these associations depend on the developmental timing of exposure remains understudied. Identifying these sensitive periods can inform when and how parenting is associated with neurodevelopment and risk for mental illness.

Objective

To characterize how harsh and warm parenting during early, middle, and late childhood are associated with brain architecture during adolescence and, in turn, psychiatric symptoms in early adulthood during the COVID-19 pandemic.

Design, Setting, and Participants

This population-based, 21-year observational, longitudinal birth cohort study of low-income youths and families from Detroit, Michigan; Toledo, Ohio; and Chicago, Illinois, used data from the Future of Families and Child Well-being Study. Data were collected from February 1998 to June 2021. Analyses were conducted from May to October 2023.

Exposures

Parent-reported harsh parenting (psychological aggression or physical aggression) and observer-rated warm parenting (responsiveness) at ages 3, 5, and 9 years.

Main Outcomes and Measures

The primary outcomes were brainwide (segregation, integration, and small-worldness), circuit (prefrontal cortex [PFC]-amygdala connectivity), and regional (betweenness centrality of amygdala and PFC) architecture at age 15 years, determined using functional magnetic resonance imaging, and youth-reported anxiety and depression symptoms at age 21 years. The structured life-course modeling approach was used to disentangle timing-dependent from cumulative associations between parenting and brain architecture.

Results

A total of 173 youths (mean [SD] age, 15.88 [0.53] years; 95 female [55%]) were included. Parental psychological aggression during early childhood was positively associated with brainwide segregation (β = 0.30; 95% CI, 0.14 to 0.45) and small-worldness (β = 0.17; 95% CI, 0.03 to 0.28), whereas parental psychological aggression during late childhood was negatively associated with PFC-amygdala connectivity (β = -0.37; 95% CI, -0.55 to -0.12). Warm parenting during middle childhood was positively associated with amygdala centrality (β = 0.23; 95% CI, 0.06 to 0.38) and negatively associated with PFC centrality (β = -0.18; 95% CI, -0.31 to -0.03). Warmer parenting during middle childhood was associated with reduced anxiety (β = -0.05; 95% CI -0.10 to -0.01) and depression (β = -0.05; 95% CI -0.10 to -0.003) during early adulthood via greater adolescent amygdala centrality.

Conclusions and Relevance

Neural associations with harsh parenting were widespread across the brain in early childhood but localized in late childhood. Neural associations with warm parenting were localized in middle childhood and, in turn, were associated with mental health during future stress. These developmentally contingent associations can inform the type and timing of interventions.

Shaping infants' social brains through vicarious social learning: the importance of positive mother-father interactions

Introduction

This study is the first to assess whether infants' developing social brains may be susceptible to the vicarious social experience of interparental positivity. Specifically, we explored whether infants' exposure to interparental positivity may vicariously shape their neural substrates of social development.

Methods

In a sample of 45 infants (M AgeMonths = 11.01; 48.9% girls), infant left-frontal resting alpha electroencephalogram (EEG) asymmetry was derived as a reliable indicator of neural substrates linked to adaptive social development. Moreover, positive characteristics of the mother-father couple relationship were assessed both by means of observation and self-report by mother and father. Importantly, various relevant covariates were considered, including interparental negativity (observed and self-reported), as well as infants' direct caregiving experiences and duration of infant exposure to mother-father relationship-dynamics (parent-report).

Results

Results indicated that higher levels of observed interparental positivity were associated with greater infant left-frontal alpha EEG asymmetry, even after accounting for covariates (β's > 0.422).

Discussion

The current study's results are first to suggest that positive vicarious social experiences in infants' day-to-day lives play a significant role for early neural development.

Association of Neighborhood Opportunity with Infant Brain Activity and Cognitive Development

BACKGROUND AND OBJECTIVES

Neighborhood socioeconomic disadvantage is associated with lower neurocognitive scores and differences in brain structure among school-age children. Associations between positive neighborhood characteristics, infant brain activity, and cognitive development are underexplored. We examined direct and indirect associations between neighborhood opportunity, brain activity, and cognitive development.

METHODS

This longitudinal cohort study included infants from 2 primary care clinics in Boston and Los Angeles. Using a sample of 65 infants, we estimated path models to examine associations between neighborhood opportunity (measured by the Child Opportunity Index), infant electroencephalography (EEG) at 6 months, and infant cognitive development (measured using the Mullen Scales of Early Learning) at 12 months. A mediation model tested whether EEG power explained associations between neighborhood opportunity and infant cognition.

RESULTS

Neighborhood opportunity positively predicted infant absolute EEG power across multiple frequency bands: low ( b = 0.12, 95% CI 0.01-0.24, p = 0.04, = 0.21); high ( b = 0.11, 95% CI 0.01-0.21, p = 0.03, = 0.23); ( b = 0.10, 95% CI 0.00-0.19, p = 0.04, = 0.20); and ( b = 0.12, 95% CI 0.02-0.22, p = 0.02, = 0.24). The results remained statistically significant after applying a Benjamini-Hochberg false discovery rate of 0.10 to adjust for multiple comparisons. No significant associations emerged between neighborhood opportunity, relative EEG power, and infant cognition. Mediation was not significant.

CONCLUSION

Neighborhood opportunity is positively associated with some forms of infant brain activity, suggesting that positive neighborhood characteristics may play a salient role in early development.

Language processing following childhood poverty: Evidence for disrupted neural networks

Childhood poverty is related to deficits in multiple cognitive domains including adult language function. It is unknown if the brain basis of language is disrupted in adults with childhood poverty backgrounds, controlling for current functioning. Fifty-one adults (age 24) from an existing longitudinal study of childhood poverty, beginning at age 9, were examined on behavioral phonological awareness (LP) and completed an event-related fMRI speech/print processing LP task. Adults from childhood poverty backgrounds exhibited lower LP in adulthood. The middle-income group exhibited greater activation of the bilateral IFG and hippocampus during language processing. In psychophysiological interaction (PPI) analyses, the childhood poverty group exhibited greater coupling between ventral Broca's and the middle temporal gyrus (MTG) as well as coupling between Wernicke's region and bilateralization. Childhood poverty disrupts language processing neural networks in adulthood, after controlling for LP, suggesting that poverty in childhood influences the neurophysiological basis for language processing into adulthood.

Experience-dependent neurodevelopment of self-regulation in adolescence

Adolescence is a period of rapid biobehavioral change, characterized in part by increased neural maturation and sensitivity to one's environment. In this review, we aim to demonstrate that self-regulation skills are tuned by adolescents' social, cultural, and socioeconomic contexts. We discuss adjacent literatures that demonstrate the importance of experience-dependent learning for adolescent development: environmental contextual influences and training paradigms that aim to improve regulation skills. We first highlight changes in prominent limbic and cortical regions-like the amygdala and medial prefrontal cortex-as well as structural and functional connectivity between these areas that are associated with adolescents' regulation skills. Next, we consider how puberty, the hallmark developmental milestone in adolescence, helps instantiate these biobehavioral adaptations. We then survey the existing literature demonstrating the ways in which cultural, socioeconomic, and interpersonal contexts drive behavioral and neural adaptation for self-regulation. Finally, we highlight promising results from regulation training paradigms that suggest training may be especially efficacious for adolescent samples. In our conclusion, we highlight some exciting frontiers in human self-regulation research as well as recommendations for improving the methodological implementation of developmental neuroimaging studies and training paradigms.

Long-term Neighborhood Poverty Effects on Internalizing Symptoms in Adolescents: Mediated Through Allostatic Load and Pubertal Timing

PURPOSE

The long-term effect of neighborhood poverty on internalizing symptoms in adolescents and the biological mechanisms underlying this association remain unclear. We defined neighborhood poverty at the village level in two dimensions: intensity (i.e., poverty rate) and duration. This study investigated how the poverty rate and duration of exposure to neighborhood poverty interact to predict internalizing symptoms in adolescents through biological mechanisms (i.e., allostatic load and early pubertal timing).

METHODS

A total of 418 adolescents (50.2% girls; 11-14 years old; mean age = 12.57 years) living in rural China participated in two waves of data collection. Path analysis was conducted to examine the mediating role of allostatic load and pubertal timing in the relationship between the duration of exposure to neighborhood poverty and internalizing symptoms. Moreover, the interactive effect between the poverty rate and duration of neighborhood poverty on the allostatic load was tested.

RESULTS

The positive association between the duration of exposure to neighborhood poverty and internalizing symptoms of adolescents was explained by elevated allostatic load and early pubertal timing after adjusting for gender, age, prior family socioeconomic states and internalizing symptoms. The duration in neighborhood poverty was a stronger predictor of allostatic load for adolescents living in high poverty rate neighborhoods than for those living in low poverty rate neighborhoods.

DISCUSSION

Neighborhood poverty gets "under the skin" through biological pathways and affects internalizing symptoms among adolescents. The findings highlight the importance of considering different dimensions of neighborhood poverty (e.g., intensity and duration) on adolescents' health.

Neighborhood poverty during childhood prospectively predicts adolescent functional brain network architecture

Family poverty has been associated with altered brain structure, function, and connectivity in youth. However, few studies have examined how disadvantage within the broader neighborhood may influence functional brain network organization. The present study leveraged a longitudinal community sample of 538 twins living in low-income neighborhoods to evaluate the prospective association between exposure to neighborhood poverty during childhood (6-10 y) with functional network architecture during adolescence (8-19 y). Using resting-state and task-based fMRI, we generated two latent measures that captured intrinsic brain organization across the whole-brain and network levels - network segregation and network segregation-integration balance. While age was positively associated with network segregation and network balance overall across the sample, these associations were moderated by exposure to neighborhood poverty. Specifically, these positive associations were observed only in youth from more, but not less, disadvantaged neighborhoods. Moreover, greater exposure to neighborhood poverty predicted reduced network segregation and network balance in early, but not middle or late, adolescence. These effects were detected both across the whole-brain system as well as specific functional networks, including fronto-parietal, default mode, salience, and subcortical systems. These findings indicate that where children live may exert long-reaching effects on the organization and development of the adolescent brain.

Socioeconomic resources in youth are linked to divergent patterns of network integration and segregation across the brain's transmodal axis

Socioeconomic resources (SER) calibrate the developing brain to the current context, which can confer or attenuate risk for psychopathology across the lifespan. Recent multivariate work indicates that SER levels powerfully influence intrinsic functional connectivity patterns across the entire brain. Nevertheless, the neurobiological meaning of these widespread alterations remains poorly understood, despite its translational promise for early risk identification, targeted intervention, and policy reform. In the present study, we leverage the resources of graph theory to precisely characterize multivariate and univariate associations between household SER and the functional integration and segregation (i.e., participation coefficient, within-module degree) of brain regions across major cognitive, affective, and sensorimotor systems during the resting state in 5,821 youth (ages 9-10 years) from the Adolescent Brain Cognitive Development (ABCD) Study. First, we establish that decomposing the brain into profiles of integration and segregation captures more than half of the multivariate association between SER and functional connectivity with greater parsimony (100-fold reduction in number of features) and interpretability. Second, we show that the topological effects of SER are not uniform across the brain; rather, higher SER levels are related to greater integration of somatomotor and subcortical systems, but greater segregation of default mode, orbitofrontal, and cerebellar systems. Finally, we demonstrate that the effects of SER are spatially patterned along the unimodal-transmodal gradient of brain organization. These findings provide critical interpretive context for the established and widespread effects of SER on brain organization, indicating that SER levels differentially configure the intrinsic functional architecture of developing unimodal and transmodal systems. This study highlights both sensorimotor and higher-order networks that may serve as neural markers of environmental stress and opportunity, and which may guide efforts to scaffold healthy neurobehavioral development among disadvantaged communities of youth.

Biology, Society, or Choice: How Do Non-Experts Interpret Explanations of Behaviour?

Explanations for human behaviour can be framed in many different ways, from the social-structural context to the individual motivation down to the neurobiological implementation. We know comparatively little about how people interpret these explanatory framings, and what they infer when one kind of explanation rather than another is made salient. In four experiments, UK general-population volunteers read vignettes describing the same behaviour, but providing explanations framed in different ways. In Study 1, we found that participants grouped explanations into 'biological', 'psychological' and 'sociocultural' clusters. Explanations with different framings were often seen as incompatible with one another, especially when one belonged to the 'biological' cluster and the other did not. In Study 2, we found that exposure to a particular explanatory framing triggered inferences beyond the information given. Specifically, psychological explanations led participants to assume the behaviour was malleable, and biological framings led them to assume it was not. In Studies 3A and 3B, we found that the choice of explanatory framing can affect people's assumptions about effective interventions. For example, presenting a biological explanation increased people's conviction that interventions like drugs would be effective, and decreased their conviction that psychological or socio-political interventions would be effective. These results illuminate the intuitive psychology of explanations, and also potential pitfalls in scientific communication. Framing an explanation in a particular way will often generate inferences in the audience-about what other factors are not causally important, how easy it is to change the behaviour, and what kinds of remedies are worth considering-that the communicator may not have anticipated and might not intend.

Prenatal socioenvironmental exposures and autism spectrum disorder: A web of confusion

Although evidence of heritability for autism spectrum disorder (ASD) is strong, studies of twin pairs suggest that at least some portion of the etiology is attributable to environmental factors, either directly or through interaction with genes. Given the multitude of environmental and psychosocial exposures that have been reported to increase atypical neurodevelopment in offspring, in this article, we summarize what prenatal air pollutant, chemical, and occupational exposures and psychosocial stressors have been reportedly associated with ASD and co-occurring neurodevelopmental disorders. We highlight consistencies in reported associations and recommend areas for research to close gaps in our understanding of environmental risk for ASD. Because this issue is of particular importance in historically marginalized communities and low- and middle-income countries, we also discuss the importance of environmental justice issues and exposure disparities in research, and we advocate for prioritizing policies to reduce disparities and improve service provision in vulnerable populations.

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.

Assessment of Parent Income and Education, Neighborhood Disadvantage, and Child Brain Structure

IMPORTANCE

Although different aspects of socioeconomic status (SES) may represent distinct risk factors for poor mental health in children, knowledge of their differential and synergistic associations with the brain is limited.

OBJECTIVE

To examine the independent associations between distinct SES factors and child brain structure.

DESIGN, SETTING, AND PARTICIPANTS

We used baseline data from participants aged 9 to 10 years in the Adolescent Brain Cognitive Development (ABCD) study. These data were collected from 21 US sites between September 2017 and August 2018. Study participants were recruited from schools to create a participant sample that closely reflects the US population.

EXPOSURES

Neighborhood disadvantage was measured using the area deprivation index. We also used data on total parent or caregiver educational attainment (in years) and household income-to-needs ratio.

MAIN OUTCOMES AND MEASURES

T1-weighted magnetic resonance imaging was used to assess measures of cortical thickness, surface area, and subcortical volume.

RESULTS

Data from 8862 ABCD participants aged 9 to 10 years were analyzed. The mean (SD) age was 119.1 (7.5) months; there were 4243 girls (47.9%) and 4619 boys (52.1%). Data on race or ethnicity were available for 8857 of 8862 participants: 173 (2.0%) were Asian, 1099 (12.4%) were Black or African American, 1688 (19.1%) were Hispanic, 4967 (56.1%) were White, and 930 (10.5%) reported multiple races or ethnicities. Using 10-fold, within-sample split-half replication, we found that neighborhood disadvantage was associated with lower cortical thickness in the following brain regions (η2 = 0.004-0.009): cuneus (B [SE] = -0.099 [0.013]; P < .001), lateral occipital (B [SE] = -0.088 [0.011]; P < .001), lateral orbitofrontal (B [SE] = -0.072 [0.012]; P < .001), lingual (B [SE] = -0.104 [0.012]; P < .001), paracentral (B [SE] = -0.086 [0.012]; P < .001), pericalcarine (B [SE] = -0.077 [0.012]; P < .001), postcentral (B [SE] = -0.069 [0.012]; P < .001), precentral (B [SE] = -0.059 [0.011]; P < .001), rostral middle frontal (B [SE] = -0.076 [0.011]; P < .001), and superior parietal (B [SE] = -0.060 [0.011]; P < .001). Exploratory analyses showed that the associations of low educational attainment or neighborhood disadvantage and low cortical thickness were attenuated in the presence of a high income-to-needs ratio (η2 = 0.003-0.007).

CONCLUSIONS AND RELEVANCE

The findings of this cross-sectional study suggest that different SES indicators have distinct associations with children's brain structure. A high income-to-needs ratio may play a protective role in the context of neighborhood disadvantage and low parent or caregiver educational attainment. This study highlights the importance of considering the joint associations of different SES indicators in future work.