Maternal depression in childhood and aggression in young adulthood: evidence for mediation by offspring amygdala-hippocampal volume ratio

Fetal Frontolimbic Connectivity Prospectively Associates With Aggression in Toddlers

Background

Aggression is a major public health concern that emerges early in development and lacks optimized treatment, highlighting need for improved mechanistic understanding regarding the etiology of aggression. The present study leveraged fetal resting-state functional magnetic resonance imaging to identify candidate neurocircuitry for the onset of aggressive behaviors before symptom emergence.

Methods

Pregnant mothers were recruited during the third trimester of pregnancy to complete a fetal resting-state functional magnetic resonance imaging scan. Mothers subsequently completed the Child Behavior Checklist to assess child aggression at 3 years postpartum (n = 79). Independent component analysis was used to define frontal and limbic regions of interest.

Results

Child aggression was not related to within-network connectivity of subcortical limbic regions or within-medial prefrontal network connectivity in fetuses. However, weaker functional coupling between the subcortical limbic network and medial prefrontal network in fetuses was prospectively associated with greater maternal-rated child aggression at 3 years of age even after controlling for maternal emotion dysregulation and toddler language ability. We observed similar, but weaker, associations between fetal frontolimbic functional connectivity and toddler internalizing symptoms.

Conclusions

Neural correlates of aggressive behavior may be detectable in utero, well before the onset of aggression symptoms. These preliminary results highlight frontolimbic connections as potential candidate neurocircuitry that should be further investigated in relation to the unfolding of child behavior and psychiatric risk.

Nutritional factors and cross-national postpartum depression prevalence: an updated meta-analysis and meta-regression of 412 studies from 46 countries

Background

Postpartum depression (PPD) is the most common complication associated with childbirth and can lead to adverse outcomes for both mothers and their children. A previous meta-analysis found that PPD prevalence varies widely across countries. One potential underexplored contributor to this cross-national variation in PPD is diet, which contributes to mental health and varies significantly around the world. Here, we sought to update the global and national estimates of PPD prevalence using systematic review and meta-analysis. Further, we examined whether cross-national variation in PPD prevalence is associated with cross-national variation in diet using meta-regression.

Methods

To estimate national rates of PPD prevalence, we conducted an updated systematic review of all papers reporting PPD prevalence using the Edinburgh Postnatal Depression Scale between 2016-2021 and combined our findings with a previous meta-analysis of articles published between 1985-2015. PPD prevalence and methods were extracted from each study. Random effects meta-analysis was used to estimate global and national PPD prevalence. To examine dietary predictors, we extracted data on sugar-sweetened beverage, fruit, vegetable, total fiber, yogurt, and seafood consumption from the Global Dietary Database. Random effects meta-regression was used to test whether between-country and within-country variation in dietary factors predicted variation in PPD prevalence, controlling for economic and methodological variables.

Results

412 studies of 792,055 women from 46 countries were identified. The global pooled prevalence of PPD was 19.18% (95% confidence interval: 18.02 to 20.34%), ranging from 3% in Singapore to 44% in South Africa. Countries that consumed more sugar-sweetened beverages (SSBs) had higher rates of PPD (Coef. = 0.325, p = 0.044, CI:0.010-0.680); Moreover, in years when higher rates of sugar-sweetened beverages were consumed in a country, there were correspondingly higher rates of PPD in that country (Coef. = 0.129, p = 0.026, CI: 0.016-0.242).

Conclusion

The global prevalence of PPD is greater than previous calculations, and drastically varies by country. Sugar-sweetened beverage consumption explained some of the national variation in PPD prevalence.

Neurobiology of Aggression-Review of Recent Findings and Relationship with Alcohol and Trauma

Aggression can be conceptualized as any behavior, physical or verbal, that involves attacking another person or animal with the intent of causing harm, pain or injury. Because of its high prevalence worldwide, aggression has remained a central clinical and public safety issue. Aggression can be caused by several risk factors, including biological and psychological, such as genetics and mental health disorders, and socioeconomic such as education, employment, financial status, and neighborhood. Research over the past few decades has also proposed a link between alcohol consumption and aggressive behaviors. Alcohol consumption can escalate aggressive behavior in humans, often leading to domestic violence or serious crimes. Converging lines of evidence have also shown that trauma and posttraumatic stress disorder (PTSD) could have a tremendous impact on behavior associated with both alcohol use problems and violence. However, although the link between trauma, alcohol, and aggression is well documented, the underlying neurobiological mechanisms and their impact on behavior have not been properly discussed. This article provides an overview of recent advances in understanding the translational neurobiological basis of aggression and its intricate links to alcoholism and trauma, focusing on behavior. It does so by shedding light from several perspectives, including in vivo imaging, genes, receptors, and neurotransmitters and their influence on human and animal behavior.

Overgrowth of the Amygdala in Children with Single Ventricle Congenital Heart Disease

Aim: Early life stress is associated with overgrowth of the amygdala, which plays a key role in the processing and memory of emotional responses. Herein, we aimed to explore the amygdala volume in children with single-ventricle congenital heart disease who experience repeated admissions during the neonatal period and infancy. Methods: We compared the amygdala volume measured using brain magnetic resonance imaging (MRI) between 40 patients after completion of the Fontan procedure and 40 age- and sex-matched control subjects Results: Age at the MRI study were 9.2 (8.5-11.1) and 10.2 (9.2-10.3) years in the Fontan and control groups, respectively. The maximum amygdala volume in the Fontan group was significantly larger than in the control group (1232 [983-1392] mm³/m² vs. 980 [728-1166] mm³/m², P < 0.001). The amygdala volume did not correlate to cardiac index (r  =  0.260) and central venous pressure (r = -0.107) in the Fontan group. Conclusions: Children with single-ventricle congenital heart disease exhibited amygdala overgrowth.

Subcortical brain volumes in young infants exposed to antenatal maternal depression: Findings from a South African birth cohort

BACKGROUND

Several studies have reported enlarged amygdala and smaller hippocampus volumes in children and adolescents exposed to maternal depression. It is unclear whether similar volumetric differences are detectable in the infants' first weeks of life, following exposure in utero. We investigated subcortical volumes in 2-to-6 week old infants exposed to antenatal maternal depression (AMD) from a South African birth cohort.

METHODS

AMD was measured with the Beck Depression Inventory 2nd edition (BDI-II) at 28-32 weeks gestation. T2-weighted structural images were acquired during natural sleep on a 3T Siemens Allegra scanner. Subcortical regions were segmented based on the University of North Carolina neonatal brain atlas. Volumetric estimates were compared between AMD-exposed (BDI-II ⩾ 20) and unexposed (BDI-II < 14) infants, adjusted for age, sex and total intracranial volume using analysis of covariance.

RESULTS

Larger volumes were observed in AMD-exposed (N = 49) compared to unexposed infants (N = 75) for the right amygdala (1.93% difference, p = 0.039) and bilateral caudate nucleus (left: 5.79% difference, p = 0.001; right: 6.09% difference, p < 0.001). A significant AMD-by-sex interaction was found for the hippocampus (left: F(1,118) = 4.80, p = 0.030; right: F(1,118) = 5.16, p = 0.025), reflecting greater volume in AMD-exposed females (left: 5.09% difference, p = 0.001, right: 3.54% difference, p = 0.010), but not males.

CONCLUSIONS

Volumetric differences in subcortical regions can be detected in AMD-exposed infants soon after birth, suggesting structural changes may occur in utero. Female infants might exhibit volumetric changes that are not observed in male infants. The potential mechanisms underlying these early volumetric differences, and their significance for long-term child mental health, require further investigation.

Problematic internet use in children according to maternal depression trajectories: A population-based cohort study with 9-year follow-up

OBJECTIVES

We investigated the association between maternal depression trajectories from pregnancy until 2 years postpartum, and problematic internet use in children at nine years of age.

METHODS

A total of 1132 mother-child pairs from the Panel Korea Study for Children were used. Maternal depression was assessed repeatedly using the Kessler scale (K-scale) (during pregnancy, and at 6, 12, and 24 months of age). Problematic internet use was assessed in children 9 years old using the K-scale. The children's behavioral problems were assessed using the Child Behavior Checklist at nine years old. Latent profile analysis was used to identify the group trajectories of maternal depression. We compared the severity of problematic internet use of the children according to the maternal depression trajectories. We also identified behavioral problems in children with problematic internet use in each maternal depression trajectory.

RESULTS

Trajectory analysis identified three group trajectories of maternal depression: no symptoms (n = 478), mild symptoms (n = 534), and moderate symptoms (n = 120). The mild and moderate maternal depression trajectory groups were more associated with high-risk internet use in 9-year-old children compared to the non-depressed group. In children with high-risk internet use, more severe behavioral problems were reported when their mothers had depression.

CONCLUSION

Maternal depression up to two years after childbirth affected problematic internet use in middle childhood.

Parental Education, Household Income, Race, and Children's Working Memory: Complexity of the Effects

Background. Considerable research has linked social determinants of health (SDoHs) such as race, parental education, and household income to school performance, and these effects may be in part due to working memory. However, a growing literature shows that these effects may be complex: while the effects of parental education may be diminished for Blacks than Whites, household income may explain such effects. Purpose. Considering race as sociological rather than a biological construct (race as a proxy of racism) and built on Minorities' Diminished Returns (MDRs), this study explored complexities of the effects of SDoHs on children's working memory. Methods. We borrowed data from the Adolescent Brain Cognitive Development (ABCD) study. The total sample was 10,418, 9- and 10-year-old children. The independent variables were race, parental education, and household income. The primary outcome was working memory measured by the NIH Toolbox Card Sorting Test. Age, sex, ethnicity, and parental marital status were the covariates. To analyze the data, we used mixed-effect regression models. Results. High parental education and household income were associated with higher and Black race was associated with lower working memory. The association between high parental education but not household income was less pronounced for Black than White children. This differential effect of parental education on working memory was explained by household income. Conclusions. For American children, parental education generates unequal working memory, depending on race. This means parental education loses some of its expected effects for Black families. It also suggests that while White children with highly educated parents have the highest working memory, Black children report lower working memory, regardless of their parental education. This inequality is mainly because of differential income in highly educated White and Black families. This finding has significant public policy and economic implications and suggests we need to do far more than equalizing education to eliminate racial inequalities in children's cognitive outcomes. While there is a need for multilevel policies that reduce the effect of racism and social stratification for middle-class Black families, equalizing income may have more returns than equalizing education.

Socioeconomic Status Inequalities Partially Mediate Racial and Ethnic Differences in Children's Amygdala Volume

BACKGROUND

While race/ethnicity and socioeconomic status (SES) impact brain structures such as the amygdala, less is known on whether or not family SES partially explains why amygdala volume is smaller for racial and ethnic minority groups.

PURPOSE

This study tested the mediating effects of family SES on racial and ethnic differences in right and left amygdala volume.

METHODS

We borrowed the structural Magnetic Resonance Imaging (sMRI) data of the Children Brain Cognitive Development (ABCD) study, a brain imaging investigation of childhood brain development in the US. The total sample was 8977, 9-10-year-old children. The independent variables were race and ethnicity. The primary outcomes were right and left amygdala volume. Age, sex, household size, and marital status were the covariates. Multiple SES indicators such as family income, subjective family SES, parental employment, parental education, and neighborhood income were the mediators. To analyze the data, we used regression models without and with our mediators. Sobel test was used to test if these mediational paths are statistically significant.

RESULTS

Black and Latino children had smaller amygdala sizes than non-Latino White children. The effects of race and ethnicity on amygdala volume were partially mediated by SES indicators, suggesting that one of the many reasons Black and Latino children have smaller volumes of right and left amygdala is their lower SES.

CONCLUSIONS

For American children, lower family and neighborhood SES indicators partially, but not fully, explain smaller amygdala sizes of Black and Latino children compared to non- Latino White children.

Subjective Socioeconomic Status and Children's Amygdala Volume: Minorities' Diminish Returns

Considerable research has suggested that low socioeconomic status (SES) negatively influences brain structure, including but not limited to decreased amygdala volume. Considering race and ethnicity as sociological rather than biological constructs, this study was built on minorities' diminished returns (MDRs) to test if the effects of family SES on the total amygdala volume is weaker for black and Latino children than white and non-Latino children. We borrowed data from the Adolescent Brain Cognitive Development (ABCD) study, a national multi-center brain imaging investigation of childhood brain development in the US. The total sample was 9380 9-10-year-old children. The independent variables were subjective family SES and parental education. The primary outcome was total amygdala volume. High subjective SES and parental education were independently associated with larger total amygdala size. The association between high subjective SES and larger total amygdala volume was less pronounced for black and Latino children than white and non-Latino children. For American children, family SES has unequal effects on amygdala size and function, a pattern that is consistent with MDRs. This result suggests that SES loses some of its expected effects for racial and ethnic minority families.

Trajectories and Predictors of Children's Early-Starting Conduct Problems: Child, Family, Genetic, and Intervention Effects

Several research teams have previously traced patterns of emerging conduct problems (CP) from early or middle childhood. The current study expands on this previous literature by using a genetically-informed, experimental, and long-term longitudinal design to examine trajectories of early-emerging conduct problems and early childhood discriminators of such patterns from the toddler period to adolescence. The sample represents a cohort of 731 toddlers and diverse families recruited based on socioeconomic, child, and family risk, varying in urbanicity and assessed on nine occasions between ages 2 and 14. In addition to examining child, family, and community level discriminators of patterns of emerging conduct problems, we were able to account for genetic susceptibility using polygenic scores and the study's experimental design to determine whether random assignment to the Family Check-Up (FCU) discriminated trajectory groups. In addition, in accord with differential susceptibility theory, we tested whether the effects of the FCU were stronger for those children with higher genetic susceptibility. Results augmented previous findings documenting the influence of child (inhibitory control [IC], gender) and family (harsh parenting, parental depression, and educational attainment) risk. In addition, children in the FCU were overrepresented in the persistent low versus persistent high CP group, but such direct effects were qualified by an interaction between the intervention and genetic susceptibility that was consistent with differential susceptibility. Implications are discussed for early identification and specifically, prevention efforts addressing early child and family risk.

Longitudinal epigenetic predictors of amygdala:hippocampus volume ratio

BACKGROUND

The ratio between amygdala:hippocampal (AH) volume has been associated with multiple psychiatric problems, including anxiety and aggression. Yet, little is known about its biological underpinnings. Here, we used a methylome-wide approach to test (a) whether DNA methylation in early life (birth, age 7) prospectively associates with total AH volume ratio in early adulthood, and (b) whether significant DNA methylation markers are influenced by prenatal risk factors.

METHODS

Analyses were based on a subsample (n = 109 males) from the Avon Longitudinal Study of Parents and Children, which included measures of prenatal risk, DNA methylation (Infinium Illumina 450k), T1-weighted brain scans and psychopathology in early adulthood (age 18-21). Amygdala and hippocampus measures were derived using Freesurfer 5.3.0. Methylation markers related to AH volume ratio across time were identified using longitudinal multilevel modeling.

RESULTS

Amygdala:hippocampal volume ratio correlated positively with age 18 psychosis-like symptoms (p = .007). Methylation of a probe in the gene SP6 associated longitudinally with (a) higher AH volume ratio (FDR q-value = .01) and (b) higher stressful life events during pregnancy (p = .046). SP6 is expressed in the hippocampus and amygdala and has been implicated in cognitive decline in Alzheimer's disease. The association between SP6 DNA methylation, AH volume ratio and psychopathology was replicated in an independent dataset of 101 patients with schizophrenia and 111 healthy controls.

CONCLUSIONS

Our findings suggest that epigenetic alterations in genes implicated in neurodevelopment may contribute to a brain-based biomarker of psychopathology.

Nucleus accumbens functional connectivity at age 20 is associated with trajectory of adolescent cannabis use and predicts psychosocial functioning in young adulthood

AIMS

(1) To identify trajectories of cannabis use across adolescence, (2) to measure the influence of cannabis use characteristics on functional connectivity of the nucleus accumbens (NAcc) and (3) to assess whether patterns of functional connectivity related to cannabis use are associated with psychosocial functioning 2 years later.

DESIGN

The Pitt Mother and Child Project (PMCP) is a prospective, longitudinal study of male youth at high risk for psychopathology based on family income and gender.

SETTING

Participants were recruited between age 6 and 17 months from the Women, Infants and Children Nutritional Supplement program (WIC) in the Pittsburgh, Pennsylvania area.

PARTICIPANTS

A total of 158 PMCP young men contributed functional magnetic resonance imaging (fMRI) and substance use data at age 20 years.

MEASUREMENTS

Latent class growth analysis was used to determine trajectories of cannabis use frequency from age 14 to 19 years. Psychophysiological interaction (PPI) analysis was used to measure functional connectivity between the NAcc and prefrontal cortex (PFC). Adolescent cannabis use trajectory, recent frequency of use and age of initiation were considered as developmental factors. We also tested whether functional connectivity was associated with depressive symptoms, anhedonia and educational attainment at age 22.

FINDINGS

We identified three distinct trajectories of adolescent cannabis use, characterized by stable high, escalating or stable low use. The cannabis use trajectory group had a significant effect on NAcc functional connectivity to the medial PFC (F = 11.32, Z = 4.04, P_{family-wise error-corrected (FWE-corr)}  = 0.000). The escalating trajectory group displayed a pattern of negative NAcc-mPFC connectivity that was linked to higher levels of depressive symptoms (r = -0.17, P < .05), anhedonia (r = -0.19, P < .05) and lower educational attainment (t = -2.77, P < .01) at age 22.

CONCLUSIONS

Pattern of cannabis use frequency across adolescence in US youth could have consequences for mood symptoms and educational attainment in early adulthood via altered function in neural reward circuitry.

The Role of Neural Plasticity in Depression: From Hippocampus to Prefrontal Cortex

Neural plasticity, a fundamental mechanism of neuronal adaptation, is disrupted in depression. The changes in neural plasticity induced by stress and other negative stimuli play a significant role in the onset and development of depression. Antidepressant treatments have also been found to exert their antidepressant effects through regulatory effects on neural plasticity. However, the detailed mechanisms of neural plasticity in depression still remain unclear. Therefore, in this review, we summarize the recent literature to elaborate the possible mechanistic role of neural plasticity in depression. Taken together, these findings may pave the way for future progress in neural plasticity studies.

EARLY CHILDHOOD PREDICTORS OF LOW-INCOME BOYS' PATHWAYS TO ANTISOCIAL BEHAVIOR IN CHILDHOOD, ADOLESCENCE, AND EARLY ADULTHOOD

Guided by a bridging model of pathways leading to low-income boys' early starting and persistent trajectories of antisocial behavior, the current article reviews evidence supporting the model from early childhood through early adulthood. Using primarily a cohort of 310 low-income boys of families recruited from Women, Infants, and Children Nutrition Supplement centers in a large metropolitan area followed from infancy to early adulthood and a smaller cohort of boys and girls followed through early childhood, we provide evidence supporting the critical role of parenting, maternal depression, and other proximal family risk factors in early childhood that are prospectively linked to trajectories of parent-reported conduct problems in early and middle childhood, youth-reported antisocial behavior during adolescence and early adulthood, and court-reported violent offending in adolescence. The findings are discussed in terms of the need to identify at-risk boys in early childhood and methods and platforms for engaging families in healthcare settings not previously used to implement preventive mental health services.

State of the Art Review: Poverty and the Developing Brain

In the United States, >40% of children are either poor or near-poor. As a group, children in poverty are more likely to experience worse health and more developmental delay, lower achievement, and more behavioral and emotional problems than their more advantaged peers; however, there is broad variability in outcomes among children exposed to similar conditions. Building on a robust literature from animal models showing that environmental deprivation or enrichment shapes the brain, there has been increasing interest in understanding how the experience of poverty may shape the brain in humans. In this review, we summarize research on the relationship between socioeconomic status and brain development, focusing on studies published in the last 5 years. Drawing on a conceptual framework informed by animal models, we highlight neural plasticity, epigenetics, material deprivation (eg, cognitive stimulation, nutrient deficiencies), stress (eg, negative parenting behaviors), and environmental toxins as factors that may shape the developing brain. We then summarize the existing evidence for the relationship between child poverty and brain structure and function, focusing on brain areas that support memory, emotion regulation, and higher-order cognitive functioning (ie, hippocampus, amygdala, prefrontal cortex) and regions that support language and literacy (ie, cortical areas of the left hemisphere). We then consider some limitations of the current literature and discuss the implications of neuroscience concepts and methods for interventions in the pediatric medical home.

Cumulative stress in childhood is associated with blunted reward-related brain activity in adulthood

Early life stress (ELS) is strongly associated with negative outcomes in adulthood, including reduced motivation and increased negative mood. The mechanisms mediating these relations, however, are poorly understood. We examined the relation between exposure to ELS and reward-related brain activity, which is known to predict motivation and mood, at age 26, in a sample followed since kindergarten with annual assessments. Using functional neuroimaging, we assayed individual differences in the activity of the ventral striatum (VS) during the processing of monetary rewards associated with a simple card-guessing task, in a sample of 72 male participants. We examined associations between a cumulative measure of ELS exposure and VS activity in adulthood. We found that greater levels of cumulative stress during childhood and adolescence predicted lower reward-related VS activity in adulthood. Extending this general developmental pattern, we found that exposure to stress early in development (between kindergarten and grade 3) was significantly associated with variability in adult VS activity. Our results provide an important demonstration that cumulative life stress, especially during this childhood period, is associated with blunted reward-related VS activity in adulthood. These differences suggest neurobiological pathways through which a history of ELS may contribute to reduced motivation and increased negative mood.