Developmental Cognitive Neuroscience

IntroductionBody mass index (BMI) is widely used to screen for weight-related health risks during adolescence. Prior neuroimaging studies have assumed a linear relationship between BMI and brain microstructure, potentially obscuring how this association varies across the BMI distribution. Using restriction spectrum imaging (RSI) in the Adolescent Brain Cognitive Development (ABCD) Study, previous work has identified positive linear associations between BMI and weight-related metrics and the restricted normalized isotropic (RNI) signal fraction in subcortical structures, but it remains unclear whether these associations are uniform across the full BMI spectrum or driven by particular portions of the distribution. MethodsWe examined the relationship between BMI percentile and voxelwise RNI in subcortical gray matter and white matter structures using data from the ABCD Study 6.1 release, which includes four imaging timepoints spanning ages 9-18 years (22,011 observations from 10,465 unique participants). Sex-stratified generalized additive mixed-effects models with smooth terms for BMI percentile, age, and pubertal development were used to model the shape of the BMI-microstructure association across the full percentile range, controlling for genetic principal components, household income, parental education, and MRI scanner/software version. ResultsThe association between BMI percentile and RNI was nonlinear in the bilateral nucleus accumbens, caudate, pallidum, putamen, thalamus, and forceps minor. A modest, positive association was present across most of the BMI range, but the rate of change accelerated markedly above the 80th percentile. This pattern was consistent across structures and sexes, though the overall magnitude of the partial effect was higher for males across most structures, while females showed steeper rates of change in most structures above the 80th percentile. Voxelwise analyses revealed spatial heterogeneity within structures, with stronger effects concentrated in specific subregions including the posterior forceps minor, dorsal pallidum, anterior putamen, and posterior thalamus. DiscussionThe relationship between BMI and subcortical brain microstructure during adolescence is not uniform but instead accelerates at the upper end of the BMI distribution, suggesting that prior linear estimates may reflect a blended average of a modest slope across most of the range and a steep slope above the 80th percentile. These findings extend the existing literature by capturing a wider developmental window, employing voxelwise rather than ROI-averaged analyses, identifying the forceps minor as a novel region of interest, and highlighting the advantages of nonlinear modeling in revealing dynamic associations.

IntroductionSustained attention and inhibition processes are fundamental components of attention that mature during adolescence, a transitive period between childhood and adulthood characterized by a rapid behavioral and cognitive development. The current study aimed to provide a better understanding of sustained attention and inhibition processes in typically developing adolescents (n = 26) aged 11-18. MethodsFunctional magnetic resonance images (fMRI) were acquired during two different modalities (the face and the scene) from a previously validated gradual{square}onset continuous (gradCPT) paradigm to evaluate sustained attention performances. In addition, we performed linear regression analyses to investigate how cerebral activation varied as a function of covariates of interest. ResultsWe showed a bilateral fronto-parieto-occipito brain activation during response inhibition regardless the type of task. Participants demonstrated better behavioral performances during the scene gradCPT. We observed a mainly left-lateralized pattern of activation in a fronto-cingulo-cerebellum area during the face gradCPT and an extended bilateral fronto-temporo-parieto-occipital activation during the scene gradCPT. Finally, we found associations between brain activity and behavioral attentional responses. ConclusionThis study gives a better understanding of the neural correlates of sustained attention and inhibition in a typically developing adolescent population.

Socioeconomic status (SES) in childhood can impact behavioral and brain development. Past work has consistently focused on the amygdala and hippocampus, two brain areas critical for emotion, memory, and learning. While there are SES differences in total amygdala and hippocampal volumes, there are many unanswered questions in this domain connected to neurobiological specificity and whether these effects vary by participant age or sex. To address these gaps, we combined multiple large neuroimaging datasets of children and adolescents with information about neurobiology and SES (N=2,765). We examined subdivisions of the amygdala and hippocampus, derived from Freesurfer, using linear mixed effects models. Higher SES was associated with larger volumes across all three amygdala subdivisions examined, the superficial cortical division, basolateral complex, and centromedial region. Within the hippocampus, SES was specifically related to volumes in the head, with no significant associations for the body or tail. Contrary to our hypotheses, we found no significant interactions between SES and participant age or sex after correcting for multiple comparisons, suggesting these associations were relatively consistent across the developmental period examined (ages 5-18) and similar for males and females. These results fill in important gaps regarding the neurobiological specificity of SES effects, demonstrating associations across functionally distinct subdivisions of these critical brain structures.

Animal and human postmortem studies provide evidence for changes in gamma-aminobutyric acid (GABA) and glutamate in prefrontal cortex (PFC) during adolescence, suggesting shifts in excitation and inhibition balance consistent with critical period plasticity. However, how GABA and glutamate change through adolescence and how the balance of these inhibitory and excitatory neurotransmitters changes is not well understood in vivo in humans. High field (7 Tesla) Magnetic Resonance Spectroscopic Imaging was used to investigate age-related changes in the balance of GABA/creatine (Cr) and glutamate/Cr in multiple developmentally-relevant regions of PFC in 144 10 to 30-year-olds. Results indicated a homogenous pattern of age-related Glu/Cr decreases across PFC regions, while age-related changes in GABA/Cr were heterogenous, with a mix of stable and decreasing age effects. Importantly, balance between glutamate/Cr and GABA/Cr in areas of prefrontal cortex increased through adolescence, suggesting the presence of critical period plasticity in PFC at this significant time of development when adult trajectories are established.

ObjectiveCardiometabolic risk factors are already detectable in childhood and adolescence, but their relations to the developing brain remains unclear. The current study tested whether poorer cardiometabolic health is associated with brain structure and microstructure development in 10-17-year-old youth. MethodsUsing the Adolescent Brain Cognitive Development Study, we analysed data from 3,527 participants with 4,433 observations across three waves. We related anthropometric (body-mass index, waist circumference), cardiovascular (systolic and diastolic blood pressure, resting heart rate), and metabolic (haemoglobin A1c, high-density lipoprotein cholesterol) indices to global cortical thickness and surface area, and to white matter fractional anisotropy and mean diffusivity. Bayesian multilevel models were fitted to estimate main and time-interaction effects, and sensitivity analyses tested within-person change, prospective prediction to the next wave, and replaced chronological age with puberty status. ResultsHigher body-mass index was associated with thinner cortex, and higher resting heart rate was associated with higher mean diffusivity, an association that strengthened over time. Other cardiometabolic measures favoured the null, and sensitivity analyses provided little evidence that wave-to-wave changes in cardiometabolic health tracked contemporaneous brain change or predicted subsequent brain structure. ConclusionAcross late childhood and adolescence, brain architecture appears largely insensitive to variation in cardiometabolic risk indices.

A growing body of literature associates increases in electronic screen time with a vast array of psychological consequences amongst adolescents, but little is known about the neurological underpinnings of this relationship. This longitudinal study examines structural and diffusion brain MRI scans from the Adolescent Brain Cognitive Development (ABCD)Study: a large multi-site study with thousands of participants. By assessing both gray matter density (GMD) and grey matter measurements of diffusion microstructure in the adolescent brain, we describe how the developmental trajectory of the brain changes with screen-based media consumption at the sub-cellular level. Grey matter microstructure was measured across 13 bilateral regions functionally implicated with screen time use, and associated with either the control or reward system. After controlling for age, sex, total brain volume, scanning site, sibling relationships, physical activity, and socioeconomic status, this study finds significant positive correlations between increased screen time and axonal signal across 6 of the 13 regions while also finding significantly decreased intracellular signal in 8 regions. Comparing these associations to normal developmental trajectories suggests adolescent age-related brain development may be accelerated by increased screen time in brain areas associated with reward processing while age-related brain development may be decelerated in regions of the control system. Highlighting the sensitivity of microstructural analysis, no significant cross-sectional or longitudinal relationship with increased screen time was found using GMD, or fractional anisotropy. This work suggests that increased screen usage during adolescent development has a complex association with brain tissue that cannot be completely described by traditional quantifications of tissue microstructure.

Introduction: The Pubertal Development Scale (PDS) is widely used for puberty assessment, yet its psychometric properties and norms are limited to research data. This study examined the psychometric properties of parent- and self-report PDS and established continuous norms in nationally representative samples. Methods: We analyzed two deidentified survey samples: a parent-report sample of children aged 6-18 (N=2000, Mage=11.37, 47.2% female, 74.9% White), and a youth self-report sample aged 12-18 (N=754, Mage=14.33, 49.6% female, 75.3% White). Both samples were representative of the U.S. population on key demographics, and the self-report sample consisted entirely of children whose parents also participated in the parent sample, thus creating parent-child dyads. Internal consistency was evaluated using Cronbach's alpha and McDonald's Omega. Cross-informant agreement was assessed with Intraclass Correlation Coefficient (ICC; two-way model, absolute agreement, single unit) and Bland-Altman plots. Age-dependent norms of each sex were established with Generalized Additive Models for Location, Scale, and Shape (GAMLSS), with 5th-95th percentile curves and reference tables provided. Results: Parent- and self-report PDS demonstrated acceptable-to-good internal consistency (Cronbach's alpha: 0.78-0.89; McDonald's omega: 0.79-0.90). Among the 754 parent-youth dyads, excellent cross-informant agreement was observed for both sexes (ICC(2,1)=0.88). Parents' and children's PDS total scores did not differ significantly for boys; for girls, parents rated pubertal development on average 0.13 points lower than children's self-report. Regardless of informants, PDS scores increased nonlinearly with age and exhibited sex-specific developmental patterns. Girls showed earlier pubertal onset, faster progression, and greater convergence toward pubertal completion by late adolescence. Discussion: The PDS demonstrated strong psychometrics in national samples, supporting its utility in the general pediatric population. The national norms provide empirical benchmarks for PDS score interpretation, strengthening its value as a broad estimation of pubertal status and a pre-screening tool for identifying early or delayed puberty.

Background: Earlier timing and faster tempo of puberty have been associated with altered brain development and increased mental health symptoms in adolescents, particularly females. However, the role of oestradiol (E2) in these associations is unclear. Methods: Using longitudinal data from the US-based Adolescent Brain Cognitive Development Study SM (ABCD Study (R), we investigated whether, in females (N ~ 3k), E2 timing (at age 10) and tempo (rate of change from age 10 to 12) were prospectively associated with mental health symptoms at age 13 via structural brain development from age 10 to 12. Linear mixed-effects models and Bayesian mediation models were fitted to investigate the aims of the study. Results: Findings showed that E2 timing was not associated with mental health symptoms. However, earlier E2 timing was associated with a greater reduction in total cortical volume, total surface area, and surface area in the superior and middle temporal cortex over time. Further, a faster E2 tempo was associated with an increase in mental health symptoms, and this association was mediated by a faster reduction in total cortical volume and total surface area over time. Conclusion: Findings suggest that earlier E2 timing and faster E2 tempo contribute to accelerated development of gray matter structure in adolescent females, and for E2 tempo, such associated brain changes may partly contribute to increased mental health risk.

The current study examined the relations between hippocampal structure (e.g., volume and neurite density) and performance on a trace eye blink conditioning (EBC) task in young children. Our first aim assessed whether individual differences in hippocampal volume were associated with trace EBC performance, using both percent Conditioned Responses (% CR) and CR onset latency or the average latency (ms) at which the child started their blink, as measures of hippocampal-dependent associative learning. Our second aim evaluated whether individual differences in hippocampal neurite density were associated with EBC performance using the same outcome measures. Typically developing 4- to 6-year-olds (N = 31; 14 girls; Mage = 5.67; SDage = 0.89) completed T1 and diffusion-weighted MRI scans and a 15-minute trace eyeblink conditioning task outside of the scanner. % CR and CR onset latency were computed across all tone-puff and tone-alone trials. While hippocampal volume was not associated with any of our EBC measures, greater hippocampal neurite density bilaterally, was associated with later CR onset. In other words, children with greater left and right hippocampal neurite density blinked closer to the US (i.e., air puff) than children with less hippocampal neurite density, indicating that structural changes in the hippocampus assisted in the accurate timing of conditioned responses.

Executive functioning in children has been linked to intrinsic brain network organization assessed during the resting state, as well as to brain network organization during the performance of cognitive tasks. Prior work has established that task-based brain networks are stronger predictors of behavior than resting state networks, yet it is unclear if tasks only strengthen relationships that exist weakly at rest or if tasks also evoke unique relationships. A lack of discernment regarding how tasks and the resting state commonly and uniquely support executive functions precludes a holistic understanding of the neurobiological basis of executive functions. This project investigated differences in brain network organization and relationships with executive function ability between the resting state and two executive function tasks, a stop signal task and an emotional n-back task, using the Adolescent Brain and Cognitive Development (ABCD) Study dataset. Both executive function tasks evoked a more integrated network organization than the resting state, and executive function ability was related to different aspects of brain network organization during the resting state and during the tasks. Further, task-related shifts in brain network organization evoked several new relationships with executive function that were not detectable during the resting state and strengthened a relationship with executive function that existed weakly during the resting state. Overall, this study establishes a distinction between common and unique features of intrinsic and task-evoked brain function that facilitate executive function in children. SignificanceExecutive functions, which encompass goal-directed behaviors critical for life success, emerge from interactions within and between networks of brain regions. Here, we tested how executive functions are linked to functional brain network interactions during the resting state, in which there are no external cognitive demands, and during executive function tasks in late childhood. We found that brain network organization during the performance of executive function tasks evoked a combination of new and strengthened relationships with executive function ability compared to the resting state. This suggests that the brain facilitates executive function performance in children through the recruitment of specific functional interactions during the enactment of executive function.

BackgroundEvidence for sex differences in cognition in childhood is established, but less is known about the underlying neural mechanisms for these differences. Recent findings suggest the existence of brain-behavior relationship heterogeneities during infancy; however, it remains unclear whether sex underlies these heterogeneities during this critical period when sex-related behavioral differences arise. MethodsA sample of 316 infants was included with resting-state functional magnetic resonance imaging scans at neonate (3 weeks), 1, and 2 years of age. We used multiple linear regression to test interactions between sex and resting-state functional connectivity on behavioral scores of working memory, inhibitory self-control, intelligence, and anxiety collected at 4 years of age. ResultsWe found six age-specific, intra-hemispheric connections showing significant and robust sex differences in functional connectivity-behavior relationships. All connections are either with the prefrontal cortex or the temporal pole, which has direct anatomical pathways to the prefrontal cortex. Sex differences in functional connectivity only emerge when associated with behavior, and not in functional connectivity alone. Furthermore, at neonate and 2 years of age, these age-specific connections displayed greater connectivity in males and lower connectivity in females in association with better behavioral scores. ConclusionsTaken together, we critically capture robust and conserved brain mechanisms that are distinct to sex and are defined by their relationship to behavioral outcomes. Our results establish brain-behavior mechanisms as an important feature in the search for sex differences during development. Plain language summaryEarly childhood differences exist in mental processes and behavior between males and females. The brain-basis for these sex differences may arise in infancy. Indeed, small brain differences in infancy may contribute to major changes in cognitive ability throughout childhood. However, few studies have examined sex differences in brain functionality in infancy and their relationship to future behaviors in early childhood. In this study, we aimed to study this relationship by using sex differences in brain functional measures in neonate, 1, and 2-year-olds and 4-year behavioral outcomes. We identified six functional connections with robust brain-behavior sex differences. These connections were unique to frontal brain regions. Also, these connections were not specific to the brain and were only evident when associated with future behavior. In brief, our analysis shows distinct age-specific brain-behavior relationships in males and females in early childhood. This is helpful for a better understanding of brain-based prediction of behavior and informed intervention of future disorders and disabilities characterized by a sex bias. HighlightsO_LIMultiple linear regression was used to test the interaction between sex and early childhood resting-state functional connectivity on future behavioral scores C_LIO_LISix age-specific, intra-hemispheric functional connections displayed sex differences C_LIO_LIMost connections exist within prefrontal regions (with one connection in the temporal pole) C_LIO_LIFunctional connections are specific to brain-behavior relationships and not in brain connectivity alone C_LIO_LISex differences in brain-behavior relationships are robust at smaller sample sizes C_LI

Individuals undergo protracted changes in cortical morphology during childhood and adolescence, coinciding with cognitive development. Studies quantifying the association between brain structure and cognition do not always assess regional cortical morphology relative to global brain measures and typically rely on mass univariate statistics or ROI-based analyses. After controlling for global brain measures, it is possible to detect a residual regionalisation pattern indicating the size or thickness of different regions relative to the total cortical surface area or mean thickness. Individual variability in regionalisation may be important for understanding and predicting between subject variability in cognitive performance. Here we sought to determine whether the relative configuration of cortical architecture across the whole cortex was associated with cognition using a novel multivariate omnibus statistical test (MOSTest) in 10,145 children aged 9-10 years from the Adolescent Brain and Cognitive Development (ABCD) Study. MOSTest is better powered to detect associations that are widely distributed across the cortex compared to methods that assume sparse associations. We then quantified the magnitude of the association between vertex-wise cortical morphology and cognitive performance using a linear weighted sum across vertices, based on the estimated vertex-wise effect sizes. We show that the relative pattern of cortical architecture, after removing the effects of global brain measures, predicted unique variance associated with cognition across different imaging modalities and cognitive domains. SIGNIFICANCE STATEMENTThis paper demonstrates a significant advance in our understanding of the relationship between cortical morphology and individual variability in cognition. There is increasing evidence that brain-behaviour associations are distributed across the cortex. Using the unprecedented sample from the Adolescent Brain and Cognitive Development (ABCD) study and a novel application of a multivariate statistical approach (MOSTest), we have discovered specific distributed regionalization patterns across the cortex associated with cognition across multiple cognitive domains. This furthers our understanding of the relationship between brain structure and cognition, namely that these associations are not sparse and localized as assumed with traditional neuroimaging analyses. This multivariate method is extremely versatile and can be used in several different applications.

Very preterm (VPT) young adolescents are at high risk of executive, behavioural and socio-emotional difficulties. Previous research has shown significant evidence of the benefits of mindfulness-based intervention (MBI) on these abilities. This study aims to assess the association between the effects of MBI on neurobehavioral functioning and changes in white-matter microstructure in VPT young adolescents who completed an 8-week MBI program. Neurobehavioural assessments and multi-shell diffusion MRI were performed before and after MBI in 32 VPT young adolescents. Combined diffusion tensor imaging (DTI) and neurite orientation dispersion and density imaging (NODDI) measures were extracted on well-defined white matter tracts (TractSeg). A multivariate data-driven approach (partial least squares correlation) was used to explore associations between MBI-related changes on neurobehavioural measures and microstructural changes. Our finding showed an enhancement of global executive functioning after MBI that was associated with a general pattern of significant increase in fractional anisotropy (FA) and decrease in axonal dispersion (ODI) in white-matter tracts involved in executive processes. Young VPT adolescents with lower gestational age at birth showed the greatest gain in white-matter microstructural changes after MBI. HighlightsO_LIVery preterm adolescents (VPT) completed an 8-week mindfulness-based intervention (MBI) C_LIO_LIImprovement in overall executive functioning was observed after MBI C_LIO_LIExecutive gain was associate with white-matter microstructural changes C_LIO_LIThe increase in microstructural properties was in tracts involved in executive processes C_LIO_LIVPT with lower gestational age show bigger gains in microstructural changes C_LI CRediT rolesVanessa Siffredi: Conceptualization; Data curation; Formal analysis; Investigation; Methodology; Project administration; Software; Visualization; Writing - original draft; Writing - review & editing - Maria Chiara Liverani: Conceptualization; Data curation; Investigation; Methodology; Project administration; Writing - review & editing. - Dimitri Van De Ville: Methodology; Resources; Software; Supervision; Writing - review & editing. - Lorena Freitas: Data curation; Investigation; Writing - review & editing. - Cristina Borradori Tolsa: Conceptualization; Funding acquisition; Investigation; Project administration; Resources; Supervision; Validation; Writing - review & editing. - Petra Susan Huppi: Conceptualization; Funding acquisition; Methodology; Project administration; Resources; Supervision; Validation; Writing - review & editing. -Russia Ha-Vinh Leuchter: Conceptualization; Funding acquisition; Investigation; Methodology; Project administration; Resources; Supervision; Validation; Writing - review & editing.

Physical health in childhood is crucial for neurobiological as well as overall development, and can shape long-term outcomes into adulthood. The landmark, longitudinal Adolescent Brain Cognitive Development StudySM (ABCD study(R)), was designed to investigate brain development and health in almost 12,000 youth who were recruited when they were 9-10 years old and will be followed through adolescence and early adulthood. The overall goal of this paper is to provide descriptive analyses of physical health measures in the ABCD study at baseline, including but not limited to sleep, physical activity and sports involvement, and body mass index, and how these measures vary across demographic groups. This paper outlines how the physical health of the ABCD sample corresponds with that of the US population and highlights important avenues for health disparity research. This manuscript will provide important information for ABCD users and help guide analyses investigating physical health as it pertains to adolescent and young adult development.

BackgroundThe COVID-19 pandemic had profound effects on developing adolescents that, to date, remain incompletely understood. Youth with preexisting mental health problems and associated brain alterations were at increased risk for higher stress and poor mental health. This study investigated impacts of adolescent pre-pandemic mental health problems and their neural correlates on stress, negative emotions and poor mental health during the first [~]15 months of the COVID-19 pandemic. MethodsN=2,641 adolescents (median age=12.0 years) from the Adolescent Brain Cognitive Development (ABCD) cohort, with pre-pandemic data on anxiety, depression, and behavioral (attention, aggression, social withdrawal, internalizing, externalizing) problems, longitudinal survey data on mental health, stress and emotions during the first [~]15 months following the outbreak, structural MRI, and resting-state fMRI. Data were analyzed using mixed effects mediation and moderation models. ResultsPreexisting mental health and behavioral problems predicted higher stress, negative affect and negative emotions ({beta}=0.09-0.21, CI=[0.03,0.32]), and lower positive affect ({beta}=-0.21 to -0.09, CI=[-0.31,-0.01]) during the first [~]6 months of the outbreak. Pre-pandemic structural characteristics of brain regions supporting social function and emotional processing (insula, superior temporal gyrus, orbitofrontal cortex, and the cerebellum) mediated some of these relationships ({beta}=0.10-0.15, CI=[0.01,0.24]). Pre-pandemic brain circuit organization moderated (attenuated) relationships between preexisting mental health and pandemic stress and negative emotions ({beta}=-0.17 to -0.06, CI=[-0.27,-0.01]). ConclusionsPreexisting mental health problems and their structural brain correlates were risk factors for youth stress and emotions during the early months of the outbreak. In addition, the organization of some brain circuits was protective and attenuated the effects of preexisting mental health issues on youth responses to the pandemics stressors.

With the evolution of ultra-low-field MRI and the recognition of antenatal maternal anaemia as an important driver of altered neurodevelopment in toddlers and children, it is critical to determine whether these effects are detectable at 64mT in infancy. The aim of this study was to assess the impact of antenatal maternal anaemia on infant brain structure across the first two years of life, using conventional high-field (3T) and ultra-low-field (64mT) MRI. This neuroimaging sub-study was embedded within Khula, an observational population-based birth cohort in South Africa. Pregnant women were enrolled antenatally and postnatally. Mother-child dyads (n=394) were followed prospectively with a subsample attending neuroimaging at approximately 3, 6, 12, 18, and 24 months of age. Anaemia was classified using WHO thresholds and neuroimaging data was processed using MiniMORPH. Linear mixed effects models were used to investigate associations between antenatal maternal anaemia status and absolute regional infant brain volumes using high-field and ultra-low-field MRI. In repeated measures high-field (n=195) and ultra-low-field (n=341) infant neuroimaging subsamples, the prevalence of antenatal maternal anaemia was 28.24% (37/131) and 29.76% (61/205), respectively. Maternal anaemia in pregnancy was associated with altered child brain structure across both MRI systems, with group differences becoming detectable at approximately 12 months. In the ultra-low-field subsample, infants born to anaemic mothers had 3.77% smaller ICV ({beta}=-0.24, p=0.004) and 3.32% smaller putamen volumes ({beta}=-0.18, p=0.04) across the first 2 years of life. The interaction between antenatal maternal anaemia and age was significant for the caudate nucleus ({beta}=-0.13, p=0.038) and the corpus callosum ({beta}=-0.13, p=0.037). Maternal anaemia in pregnancy was associated with 3.70% and 4.29% smaller caudate nucleus at 18 and 24 months of age, respectively. Similarly, infants born to anaemic mothers had 4.18% smaller corpus callosum volumes by 12 months and 7.10% smaller corpus callosum volumes by 24 months. Postnatal child anaemia and antenatal maternal iron deficiency status were not associated with total or regional child brain volumes in the ultra-low-field subsample from this cohort. Maternal anaemia remained a robust predictor of volume differences in sensitivity analyses. This study is the first to demonstrate that the impact of maternal anaemia in pregnancy on child brain structure is detectable as early as infancy. The implications of this research are two-fold; (1) informing the feasibility of ultra-low-field MRI for use in low- and middle-income countries, as well as (2) the timing and optimisation of targeted recommendations for anaemia management in both practice and policy.

Adherence to 24h movement guidelines of [≥]60min of physical activity, [≤]2h of screen time, and 9-11h of sleep has been shown to benefit cognition, physical and psychosocial health in children aged 5-13y. However, these findings are largely based on cross-sectional studies or small samples. Here we utilize data from the Adolescent Brain Cognitive Development (ABCD) study of 10000+ children aged 9-11y to examine whether adherence to 24h movement guidelines benefit cognition, BMI, psychosocial health and brain morphometric measures at baseline (T1) and 2 years later (T2). After adjustment for sociodemographic confounders in multivariable linear mixed models, we observed better cognitive scores, fewer behavioural problems, lower adiposity levels and greater gray matter volumes in children who met both sleep and screen time recommendations compared to those who met none. Longitudinal follow up further supports these findings; participants who met both recommendations at T1 and T2 evidenced better outcome measures than those who met none, even after controlling for T1 measures. These findings support consideration of integrated rather than isolated movement recommendations across the day for better cognitive, physical, psychosocial and brain health.

BackgroundHead motion is a challenge for neuroimaging research in developmental populations. However, it is unclear how transdiagnostic symptom domains including attention, disruptive behavior (e.g., externalizing behavior), and internalizing problems are linked to scanner motion in children, particularly across structural and functional MRI. The current study examined whether transdiagnostic domains of attention, disruptive behavior, and internalizing symptoms are associated with scanner motion in children during multimodal imaging. MethodsIn a sample of 9,045 children aged 9-10 years in the Adolescent Brain Cognitive Development (ABCD) Study, logistic regression and linear mixed-effects models were used to examine associations between motion and behavior. Motion was indexed using ABCD Study quality control metrics and mean framewise displacement for the following: T1-weighted structural, resting-state fMRI, diffusion MRI, Stop-Signal Task, Monetary Incentive Delay task, and Emotional n-Back task. The Child Behavior Checklist was used as a continuous measure of symptom severity. ResultsGreater attention and disruptive behavior problem severity was associated with a lower likelihood of passing motion quality control across several imaging modalities. In contrast, increased internalizing severity was associated with a higher likelihood of passing motion quality control. Increased attention and disruptive behavior problem severity was also associated with increased mean motion, whereas increased internalizing problem severity was associated with decreased mean motion. ConclusionTransdiagnostic domains emerged as predictors of motion in youths. These findings have implications for advancing development of generalizable and robust brain-based biomarkers, computational approaches for mitigating motion effects, and enhancing accessibility of imaging protocols for children with varying symptom severities.

Past studies leveraging cross-sectional data have raised questions surrounding the relationship between diffusion properties of the white matter and academic skills. Some studies have suggested that white matter properties serve as static predictors of academic skills, whereas other studies have observed no such relationship. On the other hand, longitudinal studies have suggested that within-individual changes in the white matter are linked to learning gains over time. In the present study, we look to replicate and extend the previous longitudinal results linking longitudinal changes in the white matter properties of the left arcuate fasciculus to individual differences in reading development. To do so, we analyzed diffusion MRI data, along with reading and mathematics scores in a longitudinal sample of 340 students as they progressed from 1st grade into 4th grade. Longitudinal growth models revealed that year-to-year within-individual changes in reading scores, but not math, were related to the development of the left arcuate fasciculus. These findings provide further evidence linking the dynamics of white matter development and learning in a unique sample and highlight the importance of longitudinal designs.

Adolescence is a critical period that requires balancing exploration of uncertain and novel environments while maintaining safety. This task requires sophisticated neural integration of threat and safety cues to guide behavior. Yet little work has been conducted on threat and safety processing outside of conditioning paradigms, which, while valuable, lack the complexity to identify how the adolescent brain supports distinguishing threat from safety when both are present and as task contingencies change. In the current study, we take an approach that expands on elements of differential conditioning as well as conditioned inhibition. We recorded brain responses to external threat and self-oriented protection cues to examine how the adolescent brain supports threat-safety discrimination using 7-Tesla functional magnetic resonance imaging (fMRI). Our findings reveal an adolescent transition in the neural mechanisms supporting accurate threat-safety discrimination, with younger adolescents (12-14 years) relying predominantly on the hippocampus and older adolescents (15-17 years) utilizing a more integrated circuit involving the hippocampus and anterior ventromedial prefrontal cortex (vmPFC) connectivity. Our results clarify how competition between threat and safety cues is resolved within the visual cortex, demonstrating enhanced perceptual sensitivity to protection that is independent of threat. By examining the dynamic encoding of safety to different stimuli, the current study advances our understanding of adolescent neurodevelopment and provides valuable insights into threat-safety discrimination beyond conventional conditioning models. HighlightsO_LIProtection is more strongly weighted than threat in adolescent safety estimation. C_LIO_LIHippocampus aids accurate safety detection in younger adolescents. C_LIO_LIHippocampal-vmPFC connectivity aids accurate safety detection in older adolescents. C_LIO_LIProtection enhances visual processing, reflecting perceptual prioritization. C_LI