Intergenerational impacts of trauma and hardship through parenting.

BACKGROUND: Millions of people worldwide experience severe trauma in their lifetime. Trauma has immediate and long-term effects on emotional wellbeing. Moreover, the experiences of one generation may influence subsequent generations via social and biological pathways. Poor mental health and emotion dysregulation associated with trauma may affect parenting behaviours, which may have long-lasting effects on children's development. METHODS: We use longitudinal data from a unique sample of 732 caregivers of children aged 6-36 months living in extremely poor rural households in Rwanda to examine associations of caregiver lifetime trauma, recent daily hardships, mental health, and emotion dysregulation with parenting behaviours reflecting parental acceptance and rejection of their offspring. RESULTS: Cumulative trauma exposure (ß = .234, p < .001) and recent daily hardships (ß = .323, p < .001) are associated with higher levels of internalising symptoms. Trauma (ß = .257, p < .001) and daily hardships (ß = .323, p < 0.001) are also associated with post-traumatic stress disorder (PTSD) symptoms. Internalising symptoms predict more rejection (ß = .177, p = .001), but show no association with acceptance. Caregiver PTSD symptoms predict more rejection (ß = .277, p < .001) and less acceptance (ß = -.190, p = .003). Both internalising symptoms (ß = .557, p < .001) and PTSD symptoms (ß = .606, p < .001) are strongly associated with poor emotion regulation. Indirect effects suggest that caregiver trauma and hardships affect parenting indirectly via elevated caregiver internalising symptoms and PTSD and that some of these effects are accounted for by emotion dysregulation. CONCLUSIONS: Caregiver internalising and PTSD symptoms are important mechanisms through which caregiver trauma and hardship affect parenting behaviours. Emotion dysregulation is a shared mechanism linking caregivers' mental health problems with parenting behaviours that reflect acceptance and rejection of the child. Emotion regulation is indicated as a key target for prevention of adverse effects of caregiver trauma on mental health and child wellbeing.

Promoting parent-child relationships and preventing violence via home-visiting: a pre-post cluster randomised trial among Rwandan families linked to social protection programmes.

BACKGROUND: Sugira Muryango is a father-engaged early child development and violence-prevention home-visiting programme delivered by trained lay workers. This cluster-randomised trial evaluates whether families living in extreme poverty (Ubudehe 1, the poorest category in the Government of Rwanda's wealth ranking) who receive Sugira Muryango in combination with a government-provided social protection programme demonstrate greater responsive, positive caregiving, nutrition, care seeking, hygiene, and father involvement compared with control families receiving usual care (UC). METHODS: Using detailed maps, we grouped closely spaced villages into 284 geographic clusters stratified by the type of social protection programmes operating in the village clusters; 198 clusters met all enrolment criteria. Sugira Muryango was delivered to n = 541 families in 100 treatment clusters with children aged 6-36 months living in extreme poverty. We assessed changes in outcomes in intervention and n = 508 UC control families using structured surveys and observation. Analyses were intent to treat using mixed models to accommodate clustering. RESULTS: Families receiving Sugira Muryango improved on core outcomes of parent-child relationships assessed using the Home Observation for Measurement of the Environment (Cohen's d = 0.87, 95% CI: 0.74, 0.99) and the Observation of Mother-Child Interaction (Cohen's d = 0.29, 95% CI: 0.17, 0.41). We also saw reductions in harsh discipline on items from the UNICEF MICS (OR = 0.30: 95% CI: 0.19, 0.47) and in violent victimisation of female caregivers by their partners (OR = 0.49, 95% CI: 0.24, 1.00) compared with UC. Moreover, children in families receiving SM had a 0.45 higher increase in food groups consumed in the past 24 h (Cohen's d = 0.35, 95% CI: 0.22, 0.47), increased care seeking for diarrhoea (OR = 4.43, 95% CI: 1.95, 10.10) and fever (OR = 3.28, 95% CI: 1.82, 5.89), and improved hygiene behaviours such as proper treatment of water (OR = 3.39, 95% CI: 2.16, 5.30) compared with UC. Finally, Sugira Muryango was associated with decreased caregiver depression and anxiety (OR = 0.58, 95% CI: 0.38, 0.88). CONCLUSIONS: Sugira Muryango led to improvements in caregiver behaviours linked to child development and health as well as reductions in violence. TRIAL REGISTRATION: ClinicalTrials.gov number NCT02510313.

Growth faltering is associated with altered brain functional connectivity and cognitive outcomes in urban Bangladeshi children exposed to early adversity.

BACKGROUND: Stunting affects more than 161 million children worldwide and can compromise cognitive development beginning early in childhood. There is a paucity of research using neuroimaging tools in conjunction with sensitive behavioral assays in low-income settings, which has hindered researchers' ability to explain how stunting impacts brain and behavioral development. We employed high-density EEG to examine associations among children's physical growth, brain functional connectivity (FC), and cognitive development. METHODS: We recruited participants from an urban impoverished neighborhood in Dhaka, Bangladesh. One infant cohort consisted of 92 infants whose height (length) was measured at 3, 4.5, and 6 months; EEG data were collected at 6 months; and cognitive outcomes were assessed using the Mullen Scales of Early Learning at 27 months. A second, older cohort consisted of 118 children whose height was measured at 24, 30, and 36 months; EEG data were collected at 36 months; and Intelligence Quotient (IQ) scores were assessed at 48 months. Height-for-age (HAZ) z-scores were calculated based on the World Health Organization standard. EEG FC in different frequency bands was calculated in the cortical source space. Linear regression and longitudinal path analysis were conducted to test the associations between variables, as well as the indirect effect of child growth on cognitive outcomes via brain FC. RESULTS: In the older cohort, we found that HAZ was negatively related to brain FC in the theta and beta frequency bands, which in turn was negatively related to children's IQ score at 48 months. Longitudinal path analysis showed an indirect effect of HAZ on children's IQ via brain FC in both the theta and beta bands. There were no associations between HAZ and brain FC or cognitive outcomes in the infant cohort. CONCLUSIONS: The association observed between child growth and brain FC may reflect a broad deleterious effect of malnutrition on children's brain development. The mediation effect of FC on the relation between child growth and later IQ provides the first evidence suggesting that brain FC may serve as a neural pathway by which biological adversity impacts cognitive development.

Cumulative psychosocial risk and early child development: validation and use of the Childhood Psychosocial Adversity Scale in global health research.

BACKGROUND: Evidence suggests that cumulative early psychosocial adversity can influence early child development (ECD). The Childhood Psychosocial Adversity Scale (CPAS) is a novel measure of cumulative risk designed for use in global ECD research. We describe its development and assess validity from its first application in Bangladesh, where it predicts cognitive development scores among young children. METHODS: Items were generated from literature review and qualitatively assessed for local relevance. Two-hundred and eighty-five mother-child dyads from an urban slum of Dhaka completed the CPAS at child ages 18, 24, 48, and/or 60 months. The CPAS was assessed for internal consistency, retest reliability, and convergent, incremental, and predictive validity. RESULTS: The CPAS includes subscales assessing child maltreatment, caregiver mental health, family conflict, domestic violence, and household/community psychosocial risks. In Bangladesh, subscales had good internal consistency (Cronbach's α > 0.70). Full-scale score had good 2-week test-retest reliability (intra-class correlation coefficient = 0.89; F(38,38) = 8.45, p < 0.001). Using multivariate regression, 48-month CPAS score significantly predicted 60-month intelligence quotient, accounting for more variance than socioeconomic status or malnutrition. CONCLUSIONS: The CPAS is a novel tool assessing cumulative childhood psychosocial risk. Evidence supports validity of its use in ECD research in Bangladesh, and ongoing work is applying it in additional countries.

Introduction to special issue on global child development studies.

As global child development research is taking off, this special issue provides a collection of recent research characterizing child development across the globe, validating behavioral and neuroimaging tools across diverse geographical setting and cultures, exploring relationships between risk and protective factors and diverse child outcomes, and testing novel avenues of innovative intervention. In particular, three prominent themes that emerge from this special issue are (a) research linking biology and behavior in the service of uncovering biological systems that are susceptible to experience and may mediate associations between experiences and long-term developmental outcomes in global child development research, (b) a movement towards inclusion of more detailed investigation of children's socio-emotional functions in global child development research, and (c) longitudinal studies of developmental outcomes across global settings. In this introduction we outline key themes and findings from the 25 articles included in the special issue.

Using functional near-infrared spectroscopy to assess social information processing in poor urban Bangladeshi infants and toddlers.

Children living in low-resource settings are at risk for failing to reach their developmental potential. While the behavioral outcomes of growing up in such settings are well-known, the neural mechanisms underpinning poor outcomes have not been well elucidated, particularly in the context of low- and middle-income countries. In this study, we measure brain metabolic responses to social and nonsocial stimuli in a cohort of 6- and 36-month-old Bangladeshi children. Study participants in both cohorts lived in an urban slum and were exposed to a broad range of adversity early in life including extreme poverty, malnutrition, recurrent infections, and low maternal education. We observed brain regions that responded selectively to social stimuli in both ages indicating that these specialized brain responses are online from an early age. We additionally show that the magnitude of the socially selective response is related to maternal education, maternal stress, and the caregiving environment. Ultimately our results suggest that a variety of psychosocial hazards have a measurable relationship with the developing social brain.

The relationship between biological and psychosocial risk factors and resting-state functional connectivity in 2-month-old Bangladeshi infants: A feasibility and pilot study.

Childhood poverty has been associated with structural and functional alterations in the developing brain. However, poverty does not alter brain development directly, but acts through associated biological or psychosocial risk factors (e.g. malnutrition, family conflict). Yet few studies have investigated risk factors in the context of infant neurodevelopment, and none have done so in low-resource settings such as Bangladesh, where children are exposed to multiple, severe biological and psychosocial hazards. In this feasibility and pilot study, usable resting-state fMRI data were acquired in infants from extremely poor (n = 16) and (relatively) more affluent (n = 16) families in Dhaka, Bangladesh. Whole-brain intrinsic functional connectivity (iFC) was estimated using bilateral seeds in the amygdala, where iFC has shown susceptibility to early life stress, and in sensory areas, which have exhibited less susceptibility to early life hazards. Biological and psychosocial risk factors were examined for associations with iFC. Three resting-state networks were identified in within-group brain maps: medial temporal/striatal, visual, and auditory networks. Infants from extremely poor families compared with those from more affluent families exhibited greater (i.e. less negative) iFC in precuneus for amygdala seeds; however, no group differences in iFC were observed for sensory area seeds. Height-for-age, a proxy for malnutrition/infection, was not associated with amygdala/precuneus iFC, whereas prenatal family conflict was positively correlated. Findings suggest that it is feasible to conduct infant fMRI studies in low-resource settings. Challenges and practical steps for successful implementations are discussed.

Associations between prenatal, childhood, and adolescent stress and variations in white-matter properties in young men.

OBJECTIVE: Previous studies have shown that both pre- and post-natal adversities, the latter including exposures to stress during childhood and adolescence, explain variation in structural properties of white matter (WM) in the brain. While previous studies have examined effects of independent stress exposures within one developmental period, such as childhood, we examine effects of stress across development using data from a prospective longitudinal study. More specifically, we ask how stressful events during prenatal development, childhood, and adolescence relate to variation in WM properties in early adulthood in young men recruited from a birth cohort. METHOD: Using data from 393 mother-son pairs from a community-based birth cohort from England (Avon Longitudinal Study of Parents and Children), we examined how stressful life events relate to variation in different structural properties of WM in the corpus callosum and across the whole brain in early adulthood in men aged 18-21 years. We distinguish between stress occurring during three developmental periods: a) prenatal maternal stress, b) postnatal stress within the first four years of life, c) stress during adolescence (age 12-16 years). To obtain a comprehensive quantification of variation in WM, we assess structural properties of WM using four different measures, namely fractional anisotropy (FA), mean diffusivity (MD), magnetization transfer ratio (MTR) and myelin water fraction (MWF). RESULTS: The developmental model shows that prenatal stress is associated with lower MTR and MWF in the genu and/or splenium of the corpus callosum, and with lower MTR in global (lobar) WM. Stress during early childhood is associated with higher MTR in the splenium, and stress during adolescence is associated with higher MTR in the genu and lower MD in the splenium. We see no associations between postnatal stress and variation in global (lobar) WM. CONCLUSIONS: The current study found evidence for independent effects of stress on WM properties during distinct neurodevelopmental periods. We speculate that these independent effects are due to differences in the developmental processes unfolding at different developmental time points. We suggest that associations between prenatal stress and WM properties may relate to abnormalities in neurogenesis, affecting the number and density of axons, while postnatal stress may interfere with processes related to myelination or radial growth of axons. Potential consequences of prenatal glucocorticoid exposure should be considered in obstetric care.

Inflammation-related epigenetic risk and child and adolescent mental health: A prospective study from pregnancy to middle adolescence.

In 785 mother-child (50% male) pairs from a longitudinal epidemiological birth cohort, we investigated associations between inflammation-related epigenetic polygenic risk scores (i-ePGS), environmental exposures, cognitive function, and child and adolescent internalizing and externalizing problems. We examined prenatal and postnatal effects. For externalizing problems, one prenatal effect was found: i-ePGS at birth associated with higher externalizing problems (ages 7-15) indirectly through lower cognitive function (age 7). For internalizing problems, we identified two effects. For a prenatal effect, i-ePGS at birth associated with higher internalizing symptoms via continuity in i-ePGS at age 7. For a postnatal effect, higher postnatal adversity exposure (birth through age 7) associated with higher internalizing problems (ages 7-15) via higher i-ePGS (age 7). Hence, externalizing problems were related mainly to prenatal effects involving lower cognitive function, whereas internalizing problems appeared related to both prenatal and postnatal effects. The present study supports a link between i-ePGS and child and adolescent mental health.

Biological embedding of childhood adversity: from physiological mechanisms to clinical implications.

BACKGROUND: Adverse psychosocial exposures in early life, namely experiences such as child maltreatment, caregiver stress or depression, and domestic or community violence, have been associated in epidemiological studies with increased lifetime risk of adverse outcomes, including diabetes, heart disease, cancers, and psychiatric illnesses. Additional work has shed light on the potential molecular mechanisms by which early adversity becomes "biologically embedded" in altered physiology across body systems. This review surveys evidence on such mechanisms and calls on researchers, clinicians, policymakers, and other practitioners to act upon evidence. OBSERVATIONS: Childhood psychosocial adversity has wide-ranging effects on neural, endocrine, immune, and metabolic physiology. Molecular mechanisms broadly implicate disruption of central neural networks, neuroendocrine stress dysregulation, and chronic inflammation, among other changes. Physiological disruption predisposes individuals to common diseases across the life course. CONCLUSIONS: Reviewed evidence has important implications for clinical practice, biomedical research, and work across other sectors relevant to public health and child wellbeing. Warranted changes include increased clinical screening for exposures among children and adults, scale-up of effective interventions, policy advocacy, and ongoing research to develop new evidence-based response strategies.

Developmental inter-relations between early maternal depression, contextual risks, and interpersonal stress, and their effect on later child cognitive functioning.

BACKGROUND: Maternal depression and contextual risks (e.g. poverty) are known to impact children's cognitive and social functioning. However, few published studies have examined how stress in the social environment (i.e. interpersonal stress) might developmentally inter-relate with maternal depression and contextual risks to negatively affect a child in these domains. This was the purpose of the current study. METHOD: Mother-child pairs (n = 6979) from the Avon Longitudinal Study of Parents were the study participants. Mothers reported on depression, contextual risks, and interpersonal stress between pregnancy and 33 months child age. At age 8, the children underwent cognitive assessments and the mothers reported on the children's social cognitive skills. RESULTS: Maternal depression, contextual risks, and interpersonal stress showed strong continuity and developmental inter-relatedness. Maternal depression and contextual risks directly predicted a range of child outcomes, including executive functions and social cognitive skills. Interpersonal stress worked indirectly via maternal depression and contextual risks to negatively affect child outcomes. CONCLUSION: Maternal depression and contextual risks each increased interpersonal stress in the household, which, in turn, contributed to reduced child cognitive and social functioning.

Prenatal maternal depression symptoms and nutrition, and child cognitive function.

BACKGROUND: Little is currently known about how maternal depression symptoms and unhealthy nutrition during pregnancy may developmentally interrelate to negatively affect child cognitive function. AIMS: To test whether prenatal maternal depression symptoms predict poor prenatal nutrition, and whether this in turn prospectively associates with reduced postnatal child cognitive function. METHOD: In 6979 mother-offspring pairs participating in the Avon Longitudinal Study of Parents and Children (ALSPAC) in the UK, maternal depression symptoms were assessed five times between 18 weeks gestation and 33 months old. Maternal reports of the nutritional environment were assessed at 32 weeks gestation and 47 months old, and child cognitive function was assessed at age 8 years. RESULTS: During gestation, higher depressive symptoms were related to lower levels of healthy nutrition and higher levels of unhealthy nutrition, each of which in turn was prospectively associated with reduced cognitive function. These results were robust to postnatal depression symptoms and nutrition, as well as a range of potential prenatal and postnatal confounds (i.e. poverty, teenage mother, low maternal education, parity, birth complications, substance use, criminal lifestyle, partner cruelty towards mother). CONCLUSIONS: Prenatal interventions aimed at the well-being of children of parents with depression should consider targeting the nutritional environment.

Family Violence Reduction Within a Parenting Intervention in Rwanda: A Mixed-Methods Study.

BACKGROUND AND OBJECTIVES: A mixed-methods study of mechanisms of change through which a home-visiting-based early childhood development intervention, Sugira Muryango ("strong family"), reduced violent discipline and intimate partner violence in Rwanda. METHODS: The cluster-randomized trial of Sugira Muryango enrolled socioeconomically vulnerable families with children aged 6 to 36 months in rural Rwanda. We interviewed 18 female caregivers early in the intervention, and 21 female caregivers and 11 male intimate partners were interviewed after the intervention. Coded interviews identify risk factors for violence and mechanisms of intervention-related change in violence. Quantitative analyses included 931 caregivers (52.6% female) who lived with an intimate partner to examine risk factors for violence, intervention effects, and mechanisms of violence reduction. RESULTS: The qualitative data identified daily hardships and alcohol problems as risk factors for violent discipline and intimate partner violence. Through Sugira Muryango, caregivers learned that strong relationships between partners and engagement of male caregivers in child care has positive impacts on children's development. Techniques taught by community lay workers improved communication, promoted positive parent-child interactions, and reduced intimate partner violence and violent discipline. Quantitative analyses also found that daily hardships predict violent discipline and intimate partner violence. Sugira Muryango reduced violent discipline, increased father engagement, and increased female caregiving warmth. Moreover, pre- to postintervention change in caregiving warmth was associated with reduced use of violent discipline among female caregivers and marginally associated with reduced female victimization. CONCLUSIONS: Violence reduction can be integrated into early child development programs to reduce violent discipline and intimate partner violence.

Measuring the cost-effectiveness of a home-visiting intervention to promote early child development among rural families linked to the Rwandan social protection system.

Early childhood development (ECD) programmes are heralded as a way to improve children's health and educational outcomes. However, few studies in developing countries calculate the effectiveness of quality early childhood interventions. This study estimates the cost and cost-effectiveness of the Sugira Muryango (SM) trial, a home-visiting intervention to improve ECD outcomes through positive parent-child relationships. Cost-effectiveness analysis of ECD interventions is challenging given their potential to have multiple benefits. We propose a cost-effectiveness method using a single outcome, in this case the improvement in cognitive development per home-visit session, as an indication of efficiency comparable across similar interventions. The trial intervention cost US$456 per family. This cost will likely fall below US$200 if the intervention is scaled through government systems. The cost-effectiveness analysis suggests that while SM generated a relatively small impact on markers of early development, it did so efficiently. The observed improvements in cognitive development per home-visit are similar to other home-visiting interventions of longer duration. SM by focusing on the family had benefits beyond ECD, including reductions in violence against children and intermate partner violence, further analysis is needed to include these returns in the economic evaluation.

Systemic inflammation during the first year of life is associated with brain functional connectivity and future cognitive outcomes.

The first years of life are a sensitive period of rapid neural and immune system development vulnerable to the impact of adverse experiences. Several studies support inflammation as a consequence of various adversities and an exposure negatively associated with developmental outcomes. The mechanism by which systemic inflammation may affect brain development and later cognitive outcomes remains unclear. In this longitudinal cohort study, we examine the associations between recurrent systemic inflammation, defined as C-reactive protein elevation on ≥ 2 of 4 measurements across the first year of life, electroencephalography (EEG) functional connectivity (FC) at 36 months, and composite cognitive outcomes at 3, 4, and 5 years among 122 children living in a limited-resource setting in Dhaka, Bangladesh. Recurrent systemic inflammation during the first year of life is significantly negatively associated with cognitive outcomes at 3, 4, and 5 years, after accounting for stunting and family care indicators (a measure of stimulation in the home environment). Recurrent systemic inflammation is significantly positively associated with parietal-occipital FC in the Beta band at 36 months, which in turn is significantly negatively associated with composite cognitive scores at 3 and 4 years. However, FC does not mediate the relationship between recurrent systemic inflammation and cognitive outcomes.

Associations of socioeconomic and other environmental factors with early brain development in Bangladeshi infants and children.

Studies of infants growing up in high-income countries reveal developmental changes in electroencephalography (EEG) power whereby socioeconomic factors - specifically, low SES and low income - are associated with lower EEG power in infants aged newborn to nine months. In the current paper we explore relationships of spectral EEG power across three regions (frontal, central, and parietal) and four frequency bands (theta, alpha, beta, and gamma) with socioeconomic and psychosocial factors in a cohort of n = 160 6-month-old infants and n = 187 36-month-old children living in Dhaka, Bangladesh. Household wealth is assessed as a multi-dimensional composite score encompassing income, assets, and housing materials. Psychosocial factors include maternal perceived stress and family caregiving activities. Among the 6-month-old infants we do not observe any association of household wealth or psychosocial factors with EEG power. Among the 36-month-old children, we find that household wealth is negatively associated absolute power in the beta and gamma bands across frontal, central, and parietal electrodes. We also find that higher reports of maternal perceived stress are associated with more absolute theta power in frontal and central regions in the 36-month-old children. The finding of a negative relationship of household wealth with beta and gamma power in 36-month-old children differs from findings previously observed in infants in high-income countries. Overall, findings suggest that children's environment continues to influence the development of EEG oscillations and provide support for the utility of EEG to quantify developmental effects of early life experiences on neural functional outcomes in low income countries.

EEG signatures of cognitive and social development of preschool children-a systematic review.

BACKGROUND: Early identification of preschool children who are at risk of faltering in their development is essential to ensuring that all children attain their full potential. Electroencephalography (EEG) has been used to measure neural correlates of cognitive and social development in children for decades. Effective portable and low-cost EEG devices increase the potential of its use to assess neurodevelopment in children at scale and particularly in low-resource settings. We conducted a systematic review aimed to synthesise EEG measures of cognitive and social development in 2-5-year old children. Our secondary aim was to identify how these measures differ across a) the course of development within this age range, b) gender and c) socioeconomic status (SES). METHODS AND FINDINGS: A systematic literature search identified 51 studies for inclusion in this review. Data relevant to the primary and secondary aims was extracted from these studies and an assessment for risk of bias was done, which highlighted the need for harmonisation of EEG data collection and analysis methods across research groups and more detailed reporting of participant characteristics. Studies reported on the domains of executive function (n = 22 papers), selective auditory attention (n = 9), learning and memory (n = 5), processing of faces (n = 7) and emotional stimuli (n = 8). For papers investigating executive function and selective auditory attention, the most commonly reported measures were alpha power and the amplitude and latency of positive (P1, P2, P3) and negative (N1, N2) deflections of event related potential (ERPs) components. The N170 and P1 ERP components were the most commonly reported neural responses to face and emotional faces stimuli. A mid-latency negative component and positive slow wave were used to index learning and memory, and late positive potential in response to emotional non-face stimuli. While almost half the studies described changes in EEG measures across age, only eight studies disaggregated results based on gender, and six included children from low income households to assess the impact of SES on neurodevelopment. No studies were conducted in low- and middle-income countries. CONCLUSION: This review has identified power across the EEG spectrum and ERP components to be the measures most commonly reported in studies in which preschool children engage in tasks indexing cognitive and social development. It has also highlighted the need for additional research into their changes across age and based on gender and SES.

An exploratory study of predictors of cognition in two low-income samples of infants across the first year of life.

OBJECTIVE: In this exploratory longitudinal study we assessed cognitive development in a community sample of infants born into predominantly low-income families from two different urban sites, to identify family and community factors that may associate with outcomes by 1 year of age. METHOD: Infant-mother dyads (n = 109) were recruited in Boston and Los Angeles community pediatric practices. Infant cognition was measured using the Mullen Scales of Early Learning when the infant was aged 2, 6, 9, and 12 months. Longitudinal linear mixed effects modeling and linear regression models explored potential predictors of cognitive outcomes. RESULTS: Cognitive scores were lower than the reference population mean at both 6 and 12 months. There were site differences in demographics and cognitive performance. Maternal education predicted expressive language in Boston, and speaking Spanish and lower rates of community poverty were associated with greater increases in overall cognition in Los Angeles. CONCLUSION: This exploratory study identified a number of drivers of child development that are both shared across cohorts and unique to specific community samples. Factors influencing heterogeneity within and across populations both may be important contributors to prevention and intervention in supporting healthy development among children.

Child development in the context of biological and psychosocial hazards among poor families in Bangladesh.

It is well established that low resource environments early in life can predispose children to adverse health and compromised developmental outcomes. We explore possible mechanistic pathways underlying poor developmental outcomes in children growing up in a low resource setting in urban Bangladesh. We tested associations between psychosocial risks, namely maternal distress and poor caregiving experiences, and biological risks, namely poor growth (HAZ) and inflammation (C-reactive protein: CRP), and children's developmental outcomes. Child development was measured using the Mullen Scales of Early Learning (MSEL) at 6 and 27 months in one cohort, and using the MSEL and Wechsler Preschool and Primary Scale of Intelligence (WPPSI) at 36 and 60 months respectively in another cohort. In the younger cohort, we found that more inflammation (estimated by the child's CRP level at four months) predicted lower receptive language scores at 6 months, while more frequent caregiving interactions predicted higher receptive language scores at 6 months. In the older cohort, we found that at 27 months, a child's growth measured by his or her current HAZ was positively associated with gross motor, visual reception, receptive language, and expressive language scores. In the oldest cohort, we found that higher HAZ and more frequent stimulating activities in the home predicted higher motor and language scores, whereas more inflammation (as estimated by CRP over the first two years of life) predicted lower motor scores at 36 months. At 60 months, we found that HAZ and caregiving experiences were positively associated with verbal IQ, whereas inflammation was negatively associated with verbal IQ. This work identifies malnutrition, inflammation, and caregiving as potential sites of intervention to improve neurodevelopment in children growing up in global poverty.

Neural correlates of early adversity among Bangladeshi infants.

In this paper we explore the relationship between the Visual Evoked Potential (VEP), a component of the electroencephalogram elicited by visual stimuli, and cognitive functions in children growing up in an urban slum in Bangladesh. VEPs in response to pattern-reversing checkerboards were collected in 6 month-old-infants (n = 91) and 36-month-old children (n = 112). We examine variation in the amplitude and latency of the first positive component, the P1, of the VEP in relation to cognitive scores on the Mullen Scales of Early Learning and the Wechsler Preschool and Primary Scale of Intelligence. We also examine whether children's caregiving experiences prior to the neuro-cognitive assessment explain variation in the P1 of the VEP. We find that the P1 amplitude of the VEP is related to concurrent cognitive performance in each respective cohort. We also find that the P1 amplitude at 6 months is prospectively associated with cognitive outcomes at 27 months, and the P1 amplitude at 36 months is prospectively associated with children's IQ at 60 months. We find no associations between caregiving experiences and variation in the P1 of the VEP at 6 months, yet caregiving experience do explain variation in the P1 amplitude at 36 months. Caregiving experiences also explain variation in children's concurrent and prospective cognitive functioning. The VEP may be used as a biomarker to index the neurobiological embedding of early adversity, which in turn may impact children's cognitive functions.