Socio-economic status and the developing brain in adolescence: A systematic review

Occasional cannabis use is associated with higher premorbid functioning and IQ in youth at clinical high-risk (CHR) for psychosis: Parallel findings to psychosis cohorts

BACKGROUND

Neurocognitive deficits have been widely reported in clinical high-risk for psychosis (CHR) populations. Additionally, rates of cannabis use are high among CHR youth and are associated with greater symptom severity. Cannabis use has been sometimes shown to be associated with better neurocognition in more progressed psychosis cohorts, therefore in this study we aimed to determine whether a similar pattern was present in CHR.

METHODS

CHR participants ages 12-30 from the North American Prodromal Longitudinal Study (NAPLS-3) (N = 698) were grouped according to: "minimal to no cannabis use" (n = 406), "occasional use" (n = 127), or "frequent use" (n = 165). At baseline, cannabis use groups were compared on neurocognitive tests, clinical, and functional measures. Follow-up analyses were used to model relationships between cannabis use frequency, neurocognition, premorbid, and social functioning.

RESULTS

Occasional cannabis users performed significantly better than other use-groups on measures of IQ, with similar trend-level patterns observed across neurocognitive domains. Occasional cannabis users demonstrated better social, global, and premorbid functioning compared to the other use-groups and less severe symptoms compared to the frequent use group. Follow-up structural equation modeling/path analyses found significant positive associations between premorbid functioning, social functioning, and IQ, which in turn was associated with occasional cannabis use frequency.

DISCUSSION

Better premorbid functioning positively predicts both better social functioning and higher IQ which in turn is associated with a moderate cannabis use pattern in CHR, similar to reports in first-episode and chronic psychosis samples. Better premorbid functioning likely represents a protective factor in the CHR population and predicts a better functional outcome.

Racial and ethnic socioenvironmental inequity and neuroimaging in psychiatry: a brief review of the past and recommendations for the future

Neuroimaging is a major tool that holds immense translational potential for understanding psychiatric disorder phenomenology and treatment. However, although epidemiological and social research highlights the many ways inequity and representativeness influences mental health, there is a lack of consideration of how such issues may impact neuroimaging features in psychiatric research. More specifically, the potential extent to which racialized inequities may affect underlying neurobiology and impact the generalizability of neural models of disorders is unclear. The present review synthesizes research focused on understanding the potential consequences of racial/ethnic inequities relevant to neuroimaging in psychiatry. We first discuss historical and contemporary drivers of inequities that persist today. We then discuss the neurobiological consequences of these inequities as revealed through current research, and note emergent research demonstrating the impact such inequities have on our ability to use neuroimaging to understand psychiatric disease. We end with a set of recommendations and practices to move the field towards more equitable approaches that will advance our abilities to develop truly generalizable neurobiological models of psychiatric disorders.

Population-level normative models reveal race- and socioeconomic-related variability in cortical thickness of threat neurocircuitry

The inequitable distribution of economic resources and exposure to adversity between racial groups contributes to mental health disparities within the United States. Consideration of the potential neurodevelopmental consequences, however, has been limited particularly for neurocircuitry known to regulate the emotional response to threat. Characterizing the consequences of inequity on threat neurocircuitry is critical for robust and generalizable neurobiological models of psychiatric illness. Here we use data from the Adolescent Brain and Cognitive Development Study 4.0 release to investigate the contributions of individual and neighborhood-level economic resources and exposure to discrimination. We investigate the potential appearance of race-related differences using both standard methods and through population-level normative modeling. We show that, in a sample of white and Black adolescents, racial inequities in socioeconomic factors largely contribute to the appearance of race-related differences in cortical thickness of threat neurocircuitry. The race-related differences are preserved through the use of population-level models and such models also preserve associations between cortical thickness and specific socioeconomic factors. The present findings highlight that such socioeconomic inequities largely underlie race-related differences in brain morphology. The present findings provide important new insight for the generation of generalizable neurobiological models of psychiatric illness.

Growing Up Together in Society (GUTS): A team science effort to predict societal trajectories in adolescence and young adulthood

Our society faces a great diversity of opportunities for youth. The 10-year Growing Up Together in Society (GUTS) program has the long-term goal to understand which combination of measures best predict societal trajectories, such as school success, mental health, well-being, and developing a sense of belonging in society. Our leading hypothesis is that self-regulation is key to how adolescents successfully navigate the demands of contemporary society. We aim to test these questions using socio-economic, questionnaire (including experience sampling methods), behavioral, brain (fMRI, sMRI, EEG), hormonal, and genetic measures in four large cohorts including adolescents and young adults. Two cohorts are designed as test and replication cohorts to test the developmental trajectory of self-regulation, including adolescents of different socioeconomic status thereby bridging individual, family, and societal perspectives. The third cohort consists of an entire social network to examine how neural and self-regulatory development influences and is influenced by whom adolescents and young adults choose to interact with. The fourth cohort includes youth with early signs of antisocial and delinquent behavior to understand patterns of societal development in individuals at the extreme ends of self-regulation and societal participation, and examines pathways into and out of delinquency. We will complement the newly collected cohorts with data from existing large-scale population-based and case-control cohorts. The study is embedded in a transdisciplinary approach that engages stakeholders throughout the design stage, with a strong focus on citizen science and youth participation in study design, data collection, and interpretation of results, to ensure optimal translation to youth in society.

Minimally invasive surgical approach in children treated for oesophageal atresia is associated with attention problems at school age: a prospective cohort study

The long-term neurodevelopment of children born with oesophageal atresia (OA) is unclear. Therefore, we assessed the neurocognitive domains and their predictors. Patients born with OA between February 2006 and December 2014, who were routinely seen at eight years as part of a structured prospective longitudinal follow-up program, were included. Main outcome measures were need for school support, performance in various neurocognitive domains and potential predictors of neurocognitive problems. We analysed data of 65 children with a mean (SD) age of 8.1 (0.2) years, of whom 89% with OA type C. Thirty-five (54%) surgical corrections were minimally invasive; the median (interquartile range) duration of exposure to anaesthetics in the first 24 months was 398 (296 - 710) minutes. Forty-four (68%) attended regular education without extra support and intelligence was within normal range (99-108). More than 50% had z-scores ≤ -2 on one or more neurocognitive domains, of which attention was the most frequently affected domain. The speed on the sustained attention task was significantly below normal (z-score -1.48 (2.12), p < .001), as was fluctuation of sustained attention (z-score -3.19 (3.80), p < .001). The minimally invasive approach and a lower socio-economic status (both p = 0.006) proved significant predictors for sustained attention problems in multivariable analyses.  Conclusion: Children who undergo minimally invasive surgery for OA correction are at risk for sustained attention problems at school age. Future studies unravelling the effects of perioperative events on neurodevelopment should lead to optimal surgical, anaesthesiological, and intensive care management in the neonatal period. What is Known: • School-aged children born with oesophageal atresia have normal intelligence but problems with sustained attention at eight years. What is New: • Oesophageal atresia patients, who undergo minimally invasive surgery or who have a background of lower socioeconomic status are at serious risk for sustained attention problems at school age. • Moreover, those who have been intubated for a longer period are at risk for stronger fluctuations in sustained attention.

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.

Relationships of the gut microbiome with cognitive development among healthy school-age children

Background

The gut microbiome might play a role in neurodevelopment, however, evidence remains elusive. We aimed to examine the relationship between the intestinal microbiome and cognitive development of school-age children.

Methods

This cross-sectional study included healthy Israeli Arab children from different socioeconomic status (SES). The microbiome was characterized in fecal samples by implementing 16S rRNA gene sequencing. Cognitive function was measured using Stanford-Binet test, yielding full-scale Intelligence Quotient (FSIQ) score. Sociodemographics and anthropometric and hemoglobin measurements were obtained. Multivariate models were implemented to assess adjusted associations between the gut microbiome and FSIQ score, while controlling for age, sex, SES, physical growth, and hemoglobin levels.

Results

Overall, 165 children (41.2% females) aged 6-9 years were enrolled. SES score was strongly related to both FSIQ score and the gut microbiome. Measures of α-diversity were significantly associated with FSIQ score, demonstrating a more diverse, even, and rich microbiome with increased FSIQ score. Significant differences in fecal bacterial composition were found; FSIQ score explained the highest variance in bacterial β-diversity, followed by SES score. Several taxonomic differences were significantly associated with FSIQ score, including Prevotella, Dialister, Sutterella, Ruminococcus callidus, and Bacteroides uniformis.

Conclusions

We demonstrated significant independent associations between the gut microbiome and cognitive development in school-age children.

Parental socioeconomic status is linked to cortical microstructure and language abilities in children and adolescents

Gradients in parental socioeconomic status (SES) are closely linked to important life outcomes in children and adolescents, such as cognitive abilities, school achievement, and mental health. Parental SES may also influence brain development, with several magnetic resonance imaging (MRI) studies reporting associations with youth brain morphometry. However, MRI signal intensity metrics have not been assessed, but could offer a microstructural correlate, thereby increasing our understanding of SES influences on neurobiology. We computed a parental SES score from family income, parental education and parental occupation, and assessed relations with cortical microstructure as measured by T1w/T2w ratio (n = 504, age = 3-21 years). We found negative age-stabile relations between parental SES and T1w/T2w ratio, indicating that youths from lower SES families have higher ratio in widespread frontal, temporal, medial parietal and occipital regions, possibly indicating a more developed cortex. Effect sizes were small, but larger than for conventional morphometric properties i.e. cortical surface area and thickness, which were not significantly associated with parental SES. Youths from lower SES families had poorer language related abilities, but microstructural differences did not mediate these relations. T1w/T2w ratio appears to be a sensitive imaging marker for further exploring the association between parental SES and child brain development.

Association between adverse childhood experiences and brain volumes among Japanese community-dwelling older people: Findings from the NEIGE study

BACKGROUND

Adverse childhood experiences (ACEs) can affect later-life health outcomes via brain structural differences. However, there is no sufficient empirical evidence about whether brain morphological differences remain until old ages.

OBJECTIVE

We examined the association between ACEs and brain volumes among older individuals.

PARTICIPANTS AND SETTING

Residents aged 65-84 years in Tokamachi City, Japan, were randomly recruited, and 491 participants were included in the analysis.

METHODS

ACEs were assessed with a self-reported questionnaire. The volumes of seven brain regions of interests were evaluated via structural magnetic resonance imaging.

RESULTS

In total, 143 (27.1%) participants experienced one ACE and 33 (6.7%) two or more ACEs. Participants with two or more ACEs had a larger anterior cingulate cortex volume (B = 0.346, 95% confidence interval [CI] = 0.04 to 0.66) and smaller hippocampal (B = -0.287, 95% CI = -0.58 to 0.001) and amygdala (B = -0.313, 95% CI = -0.59 to -0.03) volumes. Interestingly, we observed a distinct association between deprivation and threat. That is, deprivation was associated with a smaller amygdala volume (B = -0.164, 95% CI = -0.32 to -0.01) and threat with a larger anterior cingulate cortex volume (B = 0.401, 95% CI = 0.11 to 0.70).

CONCLUSIONS

ACEs were associated with the volumes of brain regions such as anterior cingulate cortex, hippocampus, and amygdala, which are responsible for emotion and self-regulation in older population. The effect of ACEs on the amygdala was commonly driven by deprivation experiences and that on the anterior cingulate cortex by threat.

Risk of lead exposure, subcortical brain structure, and cognition in a large cohort of 9- to 10-year-old children

BACKGROUND

Lead, a toxic metal, affects cognitive development at the lowest measurable concentrations found in children, but little is known about its direct impact on brain development. Recently, we reported widespread decreases in cortical surface area and volume with increased risks of lead exposure, primarily in children of low-income families.

METHODS AND FINDINGS

We examined associations of neighborhood-level risk of lead exposure with cognitive test performance and subcortical brain volumes. We also examined whether subcortical structure mediated associations between lead risk and cognitive performance. Our analyses employed a cross-sectional analysis of baseline data from the observational Adolescent Brain Cognitive Development (ABCD) Study. The multi-center ABCD Study used school-based enrollment to recruit a demographically diverse cohort of almost 11,900 9- and 10-year-old children from an initial 22 study sites. The analyzed sample included data from 8,524 typically developing child participants and their parents or caregivers. The primary outcomes and measures were subcortical brain structure, cognitive performance using the National Institutes of Health Toolbox, and geocoded risk of lead exposure. Children who lived in neighborhoods with greater risks of environmental lead exposure exhibited smaller volumes of the mid-anterior (partial correlation coefficient [rp] = -0.040), central (rp = -0.038), and mid-posterior corpus callosum (rp = -0.035). Smaller volumes of these three callosal regions were associated with poorer performance on cognitive tests measuring language and processing speed. The association of lead exposure risk with cognitive performance was partially mediated through callosal volume, particularly the mid-posterior corpus callosum. In contrast, neighborhood-level indicators of disadvantage were not associated with smaller volumes of these brain structures.

CONCLUSIONS

Environmental factors related to the risk of lead exposure may be associated with certain aspects of cognitive functioning via diminished subcortical brain structure, including the anterior splenium (i.e., mid-posterior corpus callosum).

Socioeconomic status and the developing brain - A systematic review of neuroimaging findings in youth

A growing literature has shown associations between socioeconomic disadvantage and neural properties (such as brain structure and function). In this review, we aimed to synthesize findings on the neural correlates of socioeconomic status (SES) in youth samples across neuroimaging modalities. We also aimed to disentangle the effects of different SES measures (e.g., parent income and education) in our synthesis. We found relatively consistent patterns of positive associations between SES and both volume and cortical surface area of frontal regions, and amygdala, hippocampal, and striatal volume (with most consistent results for composite SES indices). Despite limited longitudinal work, results suggest that SES is associated with developmental trajectories of gray matter structure. Higher SES was also found to be associated with increased fractional anisotropy of some white matter tracts, although there were more null than positive findings. Finally, methodological heterogeneity in brain function and connectivity studies prevented us from making strong inferences. Based on our findings, we make recommendations for future research, discuss the role of mitigating factors, and implications for policy.

Charting brain growth in tandem with brain templates at school age

Brain growth charts and age-normed brain templates are essential resources for researchers to eventually contribute to the care of individuals with atypical developmental trajectories. The present work generates age-normed brain templates for children and adolescents at one-year intervals and the corresponding growth charts to investigate the influences of age and ethnicity using a common pediatric neuroimaging protocol. Two accelerated longitudinal cohorts with the identical experimental design were implemented in the United States and China. Anatomical magnetic resonance imaging (MRI) of typically developing school-age children (TDC) was obtained up to three times at nominal intervals of 1.25 years. The protocol generated and compared population- and age-specific brain templates and growth charts, respectively. A total of 674 Chinese pediatric MRI scans were obtained from 457 Chinese TDC and 190 American pediatric MRI scans were obtained from 133 American TDC. Population- and age-specific brain templates were used to quantify warp cost, the differences between individual brains and brain templates. Volumetric growth charts for labeled brain network areas were generated. Shape analyses of cost functions supported the necessity of age-specific and ethnicity-matched brain templates, which was confirmed by growth chart analyses. These analyses revealed volumetric growth differences between the two ethnicities primarily in lateral frontal and parietal areas, regions which are most variable across individuals in regard to their structure and function. Age- and ethnicity-specific brain templates facilitate establishing unbiased pediatric brain growth charts, indicating the necessity of the brain charts and brain templates generated in tandem. These templates and growth charts as well as related codes have been made freely available to the public for open neuroscience (https://github.com/zuoxinian/CCS/tree/master/H3/GrowthCharts).

Impact of low-level mercury exposure on intelligence quotient in children via rice consumption

Wanshan is a city in southwest China that has several inactive mercury (Hg) mines. The local population are exposed to methylmercury (MeHg) due to the consumption of Hg contaminated rice. The relationship between Hg exposure and the cognitive functions of local children is unknown. This study investigated the relationship between hair Hg concentrations and the intelligence quotient (IQ) of 314 children aged 8-10 years, recruited from three local primary schools in Wanshan area in 2018 and 2019. IQ was evaluated using Wechsler Intelligence Scale for Children - Fourth Edition (WISC-IV). The average THg concentration in children's hair samples was 1.53 μg g^-1 (range: 0.21-12.6 μg g^-1), and 65.6% exceeded the United States Environment Protection Agency (USEPA) recommended value of 1 μg g^-1. Results of logistic regression analysis showed that children with hair Hg ≥ 1 μg g^-1 were 1.58 times more likely to have an IQ score <80, which is the clinical cut-off for borderline intellectual disability (R² = 0.20, p = 0.03). Increasing of 1 μg g^-1 hair Hg resulted in 1 point of IQ loss in Wanshan children, which was.much higher than that via fish consumption. The economical cost due to Hg exposure was estimated to be $69.8 million (9.43% of total GDP) in the Wanshan area in 2018.

Adolescent Brain Development and Progressive Legal Responsibility in the Latin American Context

In this article, we analyze the contributions of neuroscience to the development of the adolescent brain and shed additional light on the minimum age of criminal responsibility in the context of Latin America. In neurobiology, maturity is perceived to be complex because the brain's temporal development process is not uniform across all its regions. This has important consequences for adolescents' behavior; in their search for the acceptance of their peers, they are more vulnerable to pressure and more sensitive to stress than adults. Their affectivity is more unstable, and they show signs of low tolerance to frustration and important emotional reactivity, with a decrease in the capacity to self-regulate. Consequently, risky behavior presents itself more frequently during adolescence, and behaviors that transgress norms and social conventions typically peak between the ages of 17 and 19 years. However, only a small percentage of young offenders escalate their behavior to committing crimes during adulthood. In comparative law, there are considerable differences in Latin American countries' legal dispositions regarding the minimum age of criminal responsibility; Brazil, Costa Rica, and Ecuador regard the age of criminal responsibility to be 12 years, while Argentina accepts this to be 16 years. From a legal viewpoint, however, the debate about the minimum age of criminal responsibility is connected to other circumstances that, because they are still at a developmental stage, are attributed to adolescents' rights in their decision-making and understanding of autonomy (e.g., the minimum ages for voting, alcohol consumption, and medical consent). We argue that research on the development of the adolescent brain does not provide definitive answers about the exact age required for different juridical purposes. Nonetheless, the current state of knowledge does allow for reflection on the development and maturation of adolescents and the implications for considering them criminally responsible. It also validates demands for a system that provides adolescents with greater protection and that favors their healthy integral development. In any case, although a specific minimum age is not evident, this study is disposed not to recommend lowering the age of criminal responsibility, but rather increasing it.