Identifying cognitive profiles in children with neurodevelopmental disorders using online cognitive testing

Children with neurodevelopmental disorders (NDDs) such as autism spectrum disorder (ASD), and attention deficit hyperactivity disorder (ADHD) tend to exhibit similar deficits in attention and memory ability. Early screening of cognitive deficits in children with NDDs, particularly in preschool children, is fundamental to improving cognitive and academic outcomes. In order to determine cognitive profiles in children with ASD and ADHD, we developed accessible audiovisual instructions for an online battery of 13 cognitive tests. Children ages 4-16 who were diagnosed with ADHD (n = 83), or ASD (n = 37), or who were typically developing children (TD) (n = 86) were recruited. Data were analyzed using a stepwise Discriminant Analysis to determine which cognitive tasks were the strongest discriminators between the diagnostic groups. Results revealed four tasks reflective of working memory, reasoning, and attentional processes, which correctly classified approximately 53-60% of each group. The ADHD group had lower scores on attentional tasks compared to TD, while ASD group had lower scores on reasoning tasks compared to the TD children, and made more attempts across all four tasks. The results from this study stress the need for cognitive screening assessments that include domain-specific items to improve the characterization of executive function deficits and promote academic achievement in all children with NDDs.

Altered resting-state functional connectivity in newborns with hypoxic ischemic encephalopathy assessed using high-density functional near-infrared spectroscopy

Hypoxic-ischemic encephalopathy (HIE) results from a lack of oxygen to the brain during the perinatal period. HIE can lead to mortality and various acute and long-term morbidities. Improved bedside monitoring methods are needed to identify biomarkers of brain health. Functional near-infrared spectroscopy (fNIRS) can assess resting-state functional connectivity (RSFC) at the bedside. We acquired resting-state fNIRS data from 21 neonates with HIE (postmenstrual age [PMA] = 39.96), in 19 neonates the scans were acquired post-therapeutic hypothermia (TH), and from 20 term-born healthy newborns (PMA = 39.93). Twelve HIE neonates also underwent resting-state functional magnetic resonance imaging (fMRI) post-TH. RSFC was calculated as correlation coefficients amongst the time courses for fNIRS and fMRI data, respectively. The fNIRS and fMRI RSFC maps were comparable. RSFC patterns were then measured with graph theory metrics and compared between HIE infants and healthy controls. HIE newborns showed significantly increased clustering coefficients, network efficiency and modularity compared to controls. Using a support vector machine algorithm, RSFC features demonstrated good performance in classifying the HIE and healthy newborns in separate groups. Our results indicate the utility of fNIRS-connectivity patterns as potential biomarkers for HIE and fNIRS as a new bedside tool for newborns with HIE.

T2* Mapping of Placental Oxygenation to Estimate Fetal Cortical and Subcortical Maturation

This cohort study investigates the association between T2* mapping of placental oxygenation and cortical and subcortical fetal brain volumes in typically developing fetuses scanned longitudinally in the third trimester.

Sex- and age-based differences in fetal and early childhood hippocampus maturation: a cross-sectional and longitudinal analysis

The hippocampus, essential for cognitive and affective processes, develops exponentially with differential trajectories seen in girls and boys, yet less is known about its development during early fetal life until early childhood. In a cross-sectional and longitudinal study, we examined the sex-, age-, and laterality-related developmental trajectories of hippocampal volumes in fetuses, infants, and toddlers associated with age. Third trimester fetuses (27-38 weeks' gestational age), newborns (0-4 weeks' postnatal age), infants (5-50 weeks' postnatal age), and toddlers (2-3 years postnatal age) were scanned with magnetic resonance imaging. A total of 133 datasets (62 female, postmenstrual age [weeks] M = 69.38, SD = 51.39, range = 27.6-195.3) were processed using semiautomatic segmentation methods. Hippocampal volumes increased exponentially during the third trimester and the first year of life, beginning to slow at approximately 2 years. Overall, boys had larger hippocampal volumes than girls. Lateralization differences were evident, with left hippocampal growth beginning to plateau sooner than the right. This period of rapid growth from the third trimester, continuing through the first year of life, may support the development of cognitive and affective function during this period.

Structural Alterations of the Corpus Callosum in Children With Infantile Hydrocephalus

This study investigates structural alterations of the corpus callosum in children diagnosed with infantile hydrocephalus. We aim to assess both macrostructural (volume) and microstructural (diffusion tensor imaging metrics) facets of the corpus callosum, providing insights into the nature and extent of alterations associated with this condition. Eighteen patients with infantile hydrocephalus (mean age = 9 years) and 18 age- and sex-matched typically developing healthy children participated in the study. Structural magnetic resonance imaging and diffusion tensor imaging were used to assess corpus callosum volume and microstructure, respectively. Our findings reveal significant alterations in corpus callosum volume, particularly in the posterior area, as well as distinct microstructural disparities, notably pronounced in these same segments. These results highlight the intricate interplay between macrostructural and microstructural aspects in understanding the impact of infantile hydrocephalus. Examining these structural alterations provides an understanding into the mechanisms underlying the effects of infantile hydrocephalus on corpus callosum integrity, given its pivotal role in interhemispheric communication. This knowledge offers a more nuanced perspective on neurologic disorders and underscores the significance of investigating the corpus callosum's health in such contexts.

Memoir study: Investigating image memorability across developmental stages

Images have been shown to consistently differ in terms of their memorability in healthy adults: some images stick in one's mind while others are forgotten quickly. Studies have suggested that memorability is an intrinsic, continuous property of a visual stimulus that can be both measured and manipulated. Memory literature suggests that important developmental changes occur throughout adolescence that have an impact on recognition memory, yet the effect that these changes have on image memorability has not yet been investigated. In the current study, we recruited adolescents ages 11-18 (n = 273, mean = 16) to an online visual memory experiment to explore the effects of developmental changes throughout adolescence on image memorability, and determine if memorability findings in adults can be generalized to the adolescent age group. We used the online experiment to calculate adolescent memorability scores for 1,000 natural images, and compared the results to the MemCat dataset-a memorability dataset that is annotated with adult memorability scores (ages 19-27). Our study finds that memorability scores in adolescents and adults are strongly and significantly correlated (Spearman's rank correlation, r = 0.76, p < 0.001). This correlation persists even when comparing adults with developmentally different sub-groups of adolescents (ages 11-14: r = 0.67, p < 0.001; ages 15-18: r = 0.60, p < 0.001). Moreover, the rankings of image categories by mean memorability scores were identical in both adolescents and adults (including the adolescent sub-groups), indicating that broadly, certain image categories are more memorable for both adolescents and adults. Interestingly, however, adolescents experienced significantly higher false alarm rates than adults, supporting studies that show increased impulsivity and reward-seeking behaviour in adolescents. Our results reveal that the memorability of images remains consistent across individuals at different stages of development. This consistency aligns with and strengthens prior research, indicating that memorability is an intrinsic property of images. Our findings open new pathways for applying memorability studies in adolescent populations, with profound implications in fields such as education, marketing, and psychology. Our work paves the way for innovative approaches in these domains, leveraging the consistent nature of image memorability across age groups.

Association of Neonatal Midazolam Exposure With Hippocampal Growth and Working Memory Performance in Children Born Preterm

BACKGROUND AND OBJECTIVES

Early exposure to analgesics and sedatives is a key concern for later learning disorders in children. The hippocampus, a key region for learning and memory, may be selectively affected by exposure to benzodiazepines that are commonly used for sedation, particularly in the neonatal period. In this prospective cohort study, the long-term association of neonatal midazolam exposure, a widely used benzodiazepine in neonatal intensive care, with school age hippocampal growth was examined. Higher-order cognitive function in preterm born children was assessed in relation to hippocampal volumes.

METHODS

Very preterm born children underwent MRI to characterize the hippocampus and its subfields and neuropsychological testing. Generalized linear models were used to determine the predictors of 8-year hippocampal volumes. Children were assessed on the Wechsler Abbreviated Scales of Intelligence, Second Edition, and the Wechsler Intelligence Scales for Children, Fifth Edition (WISC-V).

RESULTS

A total of 140 preterm children who were 8 years of age participated, and 25 (18%) were exposed to midazolam as neonates. Reduced hippocampal volumes at age 8 years were associated with neonatal midazolam exposure (B = -400.2, 95% CI -14.37 to -786.03, p = 0.04), adjusting for neonatal clinical care factors. Boys exposed to higher doses of midazolam as neonates had smaller hippocampal volumes (χ2 = 14.4, p = 0.002) compared with nonexposed boys and girls (both, p < 0.03). Analysis of the hippocampal subfields in relation to neonatal midazolam dose revealed that higher doses were associated with smaller volumes of the subiculum (p = 0.008), a hippocampal-cortical relay region implicated in memory processes. Furthermore, smaller school age subiculum volumes predicted significantly lower working memory scores on the WISC-V (B = 0.04, 95% CI 0.01-0.07, p = 0.017).

DISCUSSION

Early midazolam exposure and the association with impaired hippocampal growth seem long-lasting and are most apparent in boys. Alterations in subiculum volumes may underlie hippocampus-dependent memory formation processes in preterm born children exposed to midazolam as neonates.

Subcortical brain volumes in neonatal hypoxic-ischemic encephalopathy

BACKGROUND

Despite treatment with therapeutic hypothermia, hypoxic-ischemic encephalopathy (HIE) is associated with adverse developmental outcomes, suggesting the involvement of subcortical structures including the thalamus and basal ganglia, which may be vulnerable to perinatal asphyxia, particularly during the acute period. The aims were: (1) to examine subcortical macrostructure in neonates with HIE compared to age- and sex-matched healthy neonates within the first week of life; (2) to determine whether subcortical brain volumes are associated with HIE severity.

METHODS

Neonates (n = 56; HIE: n = 28; Healthy newborns from the Developing Human Connectome Project: n = 28) were scanned with MRI within the first week of life. Subcortical volumes were automatically extracted from T1-weighted images. General linear models assessed between-group differences in subcortical volumes, adjusting for sex, gestational age, postmenstrual age, and total cerebral volumes. Within-group analyses evaluated the association between subcortical volumes and HIE severity.

RESULTS

Neonates with HIE had smaller bilateral thalamic, basal ganglia and right hippocampal and cerebellar volumes compared to controls (all, p < 0.02). Within the HIE group, mild HIE severity was associated with smaller volumes of the left and right basal ganglia (both, p < 0.007) and the left hippocampus and thalamus (both, p < 0.04).

CONCLUSIONS

Findings suggest that, despite advances in neonatal care, HIE is associated with significant alterations in subcortical brain macrostructure.

IMPACT

Compared to their healthy counterparts, infants with HIE demonstrate significant alterations in subcortical brain macrostructure on MRI acquired as early as 4 days after birth. Smaller subcortical volumes impacting sensory and motor regions, including the thalamus, basal ganglia, and cerebellum, were seen in infants with HIE. Mild and moderate HIE were associated with smaller subcortical volumes.

Media screen time use and mental health in school aged children during the pandemic

BACKGROUND

Children's screen time activity has increased significantly during the pandemic. Extended school closures and heightened parent stress are associated with children's behavioural difficulties and time spent watching screens. The primary aim of this study was to determine which school and household factors were associated with challenging behaviours in Canadian schoolchildren during the COVID-19 pandemic.

METHODS

This longitudinal survey study examined the association amongst screen time, internalizing and externalizing behaviours in school-aged children at two time points over the 2020-2021 academic school year. Parents completed survey measures on their parental involvement, stress levels, and their child's screen time use as well as their emotional and behavioural difficulties.

RESULTS

Children's average daily screen time was 4.40 h (SE = 18.45) at baseline and 3.89 h (SE = 16.70) at 1-year follow up, with no significant change across the school year (p = .316). Increased screen time use was associated with a greater incidence of internalizing behaviours in children (p = .03). Children who spent more time on screens and who were in households with parents reporting higher stress levels had increased internalizing behaviours (p < .001). No association between screen time use and externalizing behaviours was evident; however, parent stress was positively associated with children's externalizing behaviours (p < .001).

CONCLUSIONS

Children's screen time use has remained high during the pandemic and is associated with anxious and depressive symptoms. Children who spent more time on screens and who were in households with parents reporting higher stress levels had increased internalizing behaviours. Parent stress was positively associated with children's externalizing behaviours. Targeted family intervention plans focused on reducing parent stress and screen time use may aid in improving children's mental health during the ongoing pandemic.

Funcmasker-flex: An Automated BIDS-App for Brain Segmentation of Human Fetal Functional MRI data

Fetal functional magnetic resonance imaging (fMRI) offers critical insight into the developing brain and could aid in predicting developmental outcomes. As the fetal brain is surrounded by heterogeneous tissue, it is not possible to use adult- or child-based segmentation toolboxes. Manually-segmented masks can be used to extract the fetal brain; however, this comes at significant time costs. Here, we present a new BIDS App for masking fetal fMRI, funcmasker-flex, that overcomes these issues with a robust 3D convolutional neural network (U-net) architecture implemented in an extensible and transparent Snakemake workflow. Open-access fetal fMRI data with manual brain masks from 159 fetuses (1103 total volumes) were used for training and testing the U-net model. We also tested generalizability of the model using 82 locally acquired functional scans from 19 fetuses, which included over 2300 manually segmented volumes. Dice metrics were used to compare performance of funcmasker-flex to the ground truth manually segmented volumes, and segmentations were consistently robust (all Dice metrics ≥ 0.74). The tool is freely available and can be applied to any BIDS dataset containing fetal bold sequences. Funcmasker-flex reduces the need for manual segmentation, even when applied to novel fetal functional datasets, resulting in significant time-cost savings for performing fetal fMRI analysis.

Default mode network functional connectivity strength in utero and the association with fetal subcortical development

The default mode network is essential for higher-order cognitive processes and is composed of an extensive network of functional and structural connections. Early in fetal life, the default mode network shows strong connectivity with other functional networks; however, the association with structural development is not well understood. In this study, resting-state functional magnetic resonance imaging and anatomical images were acquired in 30 pregnant women with singleton pregnancies. Participants completed 1 or 2 MR imaging sessions, on average 3 weeks apart (43 data sets), between 28- and 39-weeks postconceptional ages. Subcortical volumes were automatically segmented. Activation time courses from resting-state functional magnetic resonance imaging were extracted from the default mode network, medial temporal lobe network, and thalamocortical network. Generalized estimating equations were used to examine the association between functional connectivity strength between default mode network-medial temporal lobe, default mode network-thalamocortical network, and subcortical volumes, respectively. Increased functional connectivity strength in the default mode network-medial temporal lobe network was associated with smaller right hippocampal, left thalamic, and right caudate nucleus volumes, but larger volumes of the left caudate. Increased functional connectivity strength in the default mode network-thalamocortical network was associated with smaller left thalamic volumes. The strong associations seen among the default mode network functional connectivity networks and regionally specific subcortical volume development indicate the emergence of short-range connectivity in the third trimester.

Hippocampus long-axis specialization throughout development: A meta-analysis

The human adult hippocampus can be subdivided into the head, or anterior hippocampus and its body and tail, or posterior hippocampus, and a wealth of functional differences along the longitudinal axis have been reported. One line of literature emphasizes specialization for different aspects of cognition, whereas another emphasizes the unique role of the anterior hippocampus in emotional processing. While some research suggests that functional differences in memory between the anterior and posterior hippocampus appear early in development, it remains unclear whether this is also the case for functional differences in emotion processing. The goal of this meta-analysis was to determine whether the long-axis functional specialization observed in adults is present earlier in development. Using a quantitative meta-analysis, long-axis functional specialization was assessed using the data from 26 functional magnetic resonance imaging studies, which included 39 contrasts and 804 participants ranging in age from 4 to 21 years. Results indicated that emotion was more strongly localized to the anterior hippocampus, with memory being more strongly localized to the posterior hippocampus, demonstrating long-axis specialization with regard to memory and emotion in children similar to that seen in adults. An additional analysis of laterality indicated that while memory was left dominant, emotion was processed bilaterally.

A radiofrequency coil for infants and toddlers

Infants and toddlers are a challenging population upon which to perform magnetic resonance imaging (MRI) of the brain, both in research and clinical settings. Because of the large range in head size during the early years of development, paediatric neuro-MRI requires a radiofrequency (RF) coil, or set of coils, that is tailored to head size to provide the highest image quality. Mitigating techniques must also be employed to reduce and correct for subject motion. This manuscript describes an RF coil with a tailored mechanical-electrical design that can adapt to the head size of 3-month-old infants to 3-year-old toddlers. The RF coil was designed with tight-fitting coil elements to improve the signal-to-noise ratio (SNR) in comparison with commercially available adult head coils, while simultaneously aiding in immobilization. The coil was designed without visual obstruction to facilitate an unimpeded view of the child's face and the potential application of camera or motion-tracking systems. Despite the lack of elements over the face, the paediatric coil produced higher SNR over most of the brain compared with adult coils, including more than twofold in the periphery. Acceleration rates of fourfold in each Cartesian direction could be achieved. High SNR allowed for short acquisition times through accelerated imaging protocols and reduced the probability of motion during a scan. Modification of the acquisition protocol, with immobilization of the head through the adjustable coil geometry, and subsequently being combined with a motion-tracking system, provides a compelling platform for scanning paediatric populations without sedation and with improved image quality.

Postnatal maternal distress, infant subcortical brain macrostructure and emotional regulation

BACKGROUND

Maternal distress is associated with an increased risk for adverse emotional development in infants, including difficulties with emotion regulation. Prenatal maternal distress has been associated with alterations in infant brain development. However, less is known about these associations with postnatal maternal distress, despite this being an important modifiable risk factor that can promote healthy brain development and emotional outcomes in infants.

METHODS & RESULTS

Infants underwent magnetic resonance imaging (MRI) and mothers completed standardized questionnaires concerning their levels of perceived distress 2-5 months postpartum. Infant emotion regulation was assessed at 8-11 months via maternal report. When examining the associations between maternal distress and infant macrostructure, maternal anxiety was associated with infant right pallidum volumes. Increased display of negative emotions at 8-11 months of age was associated with smaller hippocampal volumes and this association was stronger in girls than boys.

CONCLUSION

Findings suggest that postnatal maternal distress may be associated with early infant brain development and emphasize the importance of maternal mental health, supporting previous work. Furthermore, macrostructural properties of infant subcortical structures may be further investigated as potential biomarkers to identify infants at risk of adverse emotional outcomes.

Age-related effects on the anterior and posterior hippocampal volumes in 6-21 year olds: A model selection approach

Although recent studies support significant differences in intrinsic structure, function, and connectivity along the longitudinal axis of the hippocampus, few studies have investigated the normative development of this dimension. In addition, factors known to influence hippocampal structure, such as sex or puberty, have yet to be characterized when assessing age-related effects on its subregions. This study addresses this gap by investigating the relationship of the anterior (antHC) and posterior (postHC) hippocampus volumes with age, and how these are moderated by sex or puberty, in structural magnetic resonance imaging scans from 183 typically developing participants aged 6-21 years. Based on previous literature, we first anticipated that non-linear models would best represent the relationship between age and the antHC and postHC volumes. We found that age-related effects are region-specific, such that the antHC volume remains stable with increasing age, while the postHC shows a cubic function characterized by overall volume increase with age but a slower rate during adolescence. Second, we hypothesized that models, which include biological sex or pubertal status would best describe these relationships. Contrary to expectation, models comprising either biological sex or pubertal status did not significantly improve model performance. Further longitudinal research is needed to evaluate their effects on the antHC and postHC development.

Prenatal and postpartum maternal mental health and neonatal motor outcomes during the COVID-19 pandemic

Background

Rates of prenatal and postpartum stress and depression in pregnant individuals have increased during the COVID-19 pandemic. Perinatal maternal mental health has been linked to worse motor development in offspring, with motor deficits appearing in infancy and early childhood. We aimed to evaluate the relationship between prenatal and postpartum stress and depression and motor outcome in infants born during the COVID-19 pandemic.

Methods

One hundred and seventeen participants completed an online prospective survey study at two timepoints: during pregnancy and within 2 months postpartum. Depression was self-reported using the Edinburgh Perinatal/Postpartum Depression Scale (EPDS), and stress via the Perceived Stress Scale (PSS). Mothers reported total infant motor ability (fine and gross) using the interRAI 0–3 Developmental Domains questionnaire.

Results

Prenatal (EPDS median=10.0, interquartile range[IQR]=6.0 – 14.0, B=-0.035, 95%CI=-0.062 to -0.007, p = 0.014) and postpartum maternal depression outcomes (median=7, IQR=4–12, B=-0.037, 95%CI= -0.066 to -0.008, p = 0.012) were significantlynegatively associated with total infant motor ability. Neither pregnancy nor postpartum perceived stress was associated with infant motor function. A cluster analysis revealed that preterm and low-birth weight infants whose mothers reported elevated depressive symptoms during pregnancy and in the postpartum period had the poorest motor outcomes.

Conclusions

Prenatal and postpartum depression, but not stress, was associated with early infant motor abilities. Preterm and low-birth weight infants whose mothers reported elevated depressive symptoms maybe at-risk of experiencing poor motor outcomes. These results highlight the importance of identifying pre- and postnatal maternal mental health issues, especially during the ongoing COVID-19 pandemic.

Semi-automatic segmentation of the fetal brain from magnetic resonance imaging

BACKGROUND

Volumetric measurements of fetal brain maturation in the third trimester of pregnancy are key predictors of developmental outcomes. Improved understanding of fetal brain development trajectories may aid in identifying and clinically managing at-risk fetuses. Currently, fetal brain structures in magnetic resonance images (MRI) are often manually segmented, which requires both time and expertise. To facilitate the targeting and measurement of brain structures in the fetus, we compared the results of five segmentation methods applied to fetal brain MRI data to gold-standard manual tracings.

METHODS

Adult women with singleton pregnancies (n = 21), of whom five were scanned twice, approximately 3 weeks apart, were recruited [26 total datasets, median gestational age (GA) = 34.8, IQR = 30.9-36.6]. T2-weighted single-shot fast spin echo images of the fetal brain were acquired on 1.5T and 3T MRI scanners. Images were first combined into a single 3D anatomical volume. Next, a trained tracer manually segmented the thalamus, cerebellum, and total cerebral volumes. The manual segmentations were compared with five automatic methods of segmentation available within Advanced Normalization Tools (ANTs) and FMRIB's Linear Image Registration Tool (FLIRT) toolboxes. The manual and automatic labels were compared using Dice similarity coefficients (DSCs). The DSC values were compared using Friedman's test for repeated measures.

RESULTS

Comparing cerebellum and thalamus masks against the manually segmented masks, the median DSC values for ANTs and FLIRT were 0.72 [interquartile range (IQR) = 0.6-0.8] and 0.54 (IQR = 0.4-0.6), respectively. A Friedman's test indicated that the ANTs registration methods, primarily nonlinear methods, performed better than FLIRT (p < 0.001).

CONCLUSION

Deformable registration methods provided the most accurate results relative to manual segmentation. Overall, this semi-automatic subcortical segmentation method provides reliable performance to segment subcortical volumes in fetal MR images. This method reduces the costs of manual segmentation, facilitating the measurement of typical and atypical fetal brain development.

Association of Pediatric Buccal Epigenetic Age Acceleration With Adverse Neonatal Brain Growth and Neurodevelopmental Outcomes Among Children Born Very Preterm With a Neonatal Infection

IMPORTANCE

Very preterm neonates (24-32 weeks' gestation) remain at a higher risk of morbidity and neurodevelopmental adversity throughout their lifespan. Because the extent of prematurity alone does not fully explain the risk of adverse neonatal brain growth or neurodevelopmental outcomes, there is a need for neonatal biomarkers to help estimate these risks in this population.

OBJECTIVES

To characterize the pediatric buccal epigenetic (PedBE) clock-a recently developed tool to measure biological aging-among very preterm neonates and to assess its association with the extent of prematurity, neonatal comorbidities, neonatal brain growth, and neurodevelopmental outcomes at 18 months of age.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study was conducted in 2 neonatal intensive care units of 2 hospitals in Toronto, Ontario, Canada. A total of 35 very preterm neonates (24-32 weeks' gestation) were recruited in 2017 and 2018, and neuroimaging was performed and buccal swab samples were acquired at 2 time points: the first in early life (median postmenstrual age, 32.9 weeks [IQR, 32.0-35.0 weeks]) and the second at term-equivalent age (TEA) at a median postmenstrual age of 43.0 weeks (IQR, 41.0-46.0 weeks). Follow-ups for neurodevelopmental assessments were completed in 2019 and 2020. All neonates in this cohort had at least 1 infection because they were originally enrolled to assess the association of neonatal infection with neurodevelopment. Neonates with congenital malformations, genetic syndromes, or congenital TORCH (toxoplasmosis, rubella, cytomegalovirus, herpes and other agents) infection were excluded.

EXPOSURES

The extent of prematurity was measured by gestational age at birth and PedBE age difference. PedBE age was computed using DNA methylation obtained from 94 age-informative CpG (cytosine-phosphate-guanosine) sites. PedBE age difference (weeks) was calculated by subtracting PedBE age at each time point from the corresponding postmenstrual age.

MAIN OUTCOMES AND MEASURES

Total cerebral volumes and cerebral growth during the neonatal intensive care unit period were obtained from magnetic resonance imaging scans at 2 time points: approximately the first 2 weeks of life and at TEA. Bayley Scales of Infant and Toddler Development, Third Edition, were used to assess neurodevelopmental outcomes at 18 months.

RESULTS

Among 35 very preterm neonates (21 boys [60.0%]; median gestational age, 27.0 weeks [IQR, 25.9-29.9 weeks]; 23 [65.7%] born extremely preterm [<28 weeks' gestation]), extremely preterm neonates had an accelerated PedBE age compared with neonates born at a later gestational age (β = 9.0; 95% CI, 2.7-15.3; P = .01). An accelerated PedBE age was also associated with smaller cerebral volumes (β = -5356.8; 95% CI, -6899.3 to -2961.7; P = .01) and slower cerebral growth (β = -2651.5; 95% CI, -5301.2 to -1164.1; P = .04); these associations remained significant after adjusting for clinical neonatal factors. These findings were significant at TEA but not earlier in life. Similarly, an accelerated PedBE age at TEA was associated with lower cognitive (β = -0.4; 95% CI, -0.8 to -0.03; P = .04) and language (β = -0.6; 95% CI, -1.1 to -0.06; P = .02) scores at 18 months.

CONCLUSIONS AND RELEVANCE

This cohort study of very preterm neonates suggests that biological aging may be associated with impaired brain growth and neurodevelopmental outcomes. The associations between epigenetic aging and adverse neonatal brain health warrant further attention.

Anxiety in children and youth with autism spectrum disorder and the association with amygdala subnuclei structure

Autism spectrum disorder (ASD) is clinically characterized by social and communication difficulties as well as repetitive behaviors. Many children with ASD also suffer from anxiety, which has been associated with alterations in amygdala structure. In this work, the association between amygdala subnuclei volumes and anxiety was assessed in a cohort of 234 participants (mean age = 11.0 years, SD = 3.9, 95 children with ASD, 139 children were non-autistic). Children underwent magnetic resonance imaging. Amygdala subnuclei volumes were extracted automatically. Anxiety was assessed using the Screen for Child Anxiety Related Disorders, the Child Behavior Checklist, and the Strength and Difficulties Questionnaire. Children with ASD had higher anxiety scores relative to non-autistic children on all anxiety measures (all, p < 0.05). Anxiety levels were significantly predicted in children with ASD by right basal (right: B = 0.235, p = 0.002) and paralaminar (PL) (B = −0.99, p = 0.009) volumes. Basal nuclei receive multisensory information from cortical and subcortical areas and have extensive projections within the limbic system while the PL nuclei are involved in emotional processing. Alterations in basal and PL nuclei in children with ASD and the association with anxiety may reflect morphological changes related to in the neurocircuitry of anxiety in ASD.

Lay abstract

Autism spectrum disorder (ASD) is clinically characterized by social communication difficulties as well as restricted and repetitive patterns of behavior. In addition, children with ASD are more likely to experience anxiety compared with their peers who do not have ASD. Recent studies suggest that atypical amygdala structure, a brain region involved in emotions, may be related to anxiety in children with ASD. However, the amygdala is a complex structure composed of heterogeneous subnuclei, and few studies to date have focused on how amygdala subnuclei relate to in anxiety in this population. The current sample consisted of 95 children with ASD and 139 non-autistic children, who underwent magnetic resonance imaging (MRI) and assessments for anxiety. The amygdala volumes were automatically segmented. Results indicated that children with ASD had elevated anxiety scores relative to peers without ASD. Larger basal volumes predicted greater anxiety in children with ASD, and this association was not seen in non-autistic children. Findings converge with previous literature suggesting ASD children suffer from higher levels of anxiety than non-autistic children, which may have important implications in treatment and interventions. Our results suggest that volumetric estimation of amygdala’s subregions in MRI may reveal specific anxiety-related associations in children with ASD.

Machine learning-based predictive modeling of resilience to stressors in pregnant women during COVID-19: A prospective cohort study

During the COVID-19 pandemic, pregnant women have been at high risk for psychological distress. Lifestyle factors may be modifiable elements to help reduce and promote resilience to prenatal stress. We used Machine-Learning (ML) algorithms applied to questionnaire data obtained from an international cohort of 804 pregnant women to determine whether physical activity and diet were resilience factors against prenatal stress, and whether stress levels were in turn predictive of sleep classes. A support vector machine accurately classified perceived stress levels in pregnant women based on physical activity behaviours and dietary behaviours. In turn, we classified hours of sleep based on perceived stress levels. This research adds to a developing consensus concerning physical activity and diet, and the association with prenatal stress and sleep in pregnant women. Predictive modeling using ML approaches may be used as a screening tool and to promote positive health behaviours for pregnant women.

Amygdala subnuclei volumes and anxiety behaviors in children and adolescents with autism spectrum disorder, attention deficit hyperactivity disorder, and obsessive-compulsive disorder

Alterations in the structural maturation of the amygdala subnuclei volumes are associated with anxiety behaviors in adults and children with neurodevelopmental and associated disorders. This study investigated the relationship between amygdala subnuclei volumes and anxiety in 233 children and adolescents (mean age = 11.02 years; standard deviation = 3.17) with autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD), and children with obsessive compulsive disorder (OCD), as well as typically developing (TD) children. Parents completed the Child Behavior Checklist (CBCL), and the children underwent structural MRI at 3 T. FreeSurfer software was used to automatically segment the amygdala subnuclei. A general linear model revealed that children and adolescents with ASD, ADHD, and OCD had higher anxiety scores compared to TD children (p < .001). A subsequent interaction analysis revealed that children with ASD (B = 0.09, p < .0001) and children with OCD (B = 0.1, p < .0001) who had high anxiety had larger right central nuclei volumes compared with TD children. Similar results were obtained for the right anterior amygdaloid area. Amygdala subnuclei volumes may be key to identifying children with neurodevelopmental disorders or those with OCD who are at high risk for anxiety. Findings may inform the development of targeted behavioral interventions to address anxiety behaviors and to assess the downstream effects of such interventions.

Joint attention in infants at high familial risk for autism spectrum disorder and the association with thalamic and hippocampal macrostructure

Autism spectrum disorder (ASD) is a heritable neurodevelopmental disorder. Infants diagnosed with ASD can show impairments in spontaneous gaze-following and will seldom engage in joint attention (JA). The ability to initiate JA (IJA) can be more significantly impaired than the ability to respond to JA (RJA). In a longitudinal study, 101 infants who had a familial risk for ASD were enrolled (62% males). Participants completed magnetic resonance imaging scans at 4 or 6 months of age. Subcortical volumes (thalamus, hippocampus, amygdala, basal ganglia, ventral diencephalon, and cerebellum) were automatically extracted. Early gaze and JA behaviors were assessed with standardized measures. The majority of infants were IJA nonresponders (n = 93, 92%), and over half were RJA nonresponders (n = 50, 52%). In the nonresponder groups, models testing the association of subcortical volumes with later ASD diagnosis accounted for age, sex, and cerebral volumes. In the nonresponder IJA group, using regression method, the left hippocampus (B = −0.009, aOR = 0.991, P = 0.025), the right thalamus (B = −0.016, aOR = 0.984, P = 0.026), as well as the left thalamus (B = 0.015, aOR = 1.015, P = 0.019), predicted later ASD diagnosis. Alterations in thalamic and hippocampal macrostructure in at-risk infants who do not engage in IJA may reflect an enhanced vulnerability and may be the key predictors of later ASD development.

Neonatal pain, thalamic development and sensory processing behaviour in children born very preterm

BACKGROUND

Altered sensory processing is commonly reported in children born very preterm (≤32 weeks' gestational age [GA]). The immature nervous system, particularly the development of connections from the thalamus to the cortex, may show enhanced vulnerability to excessive sensory stimulation, and may contribute to altered sensory processing. Our objective was to determine whether sensory processing assessed at preschool-aged in children born very preterm was predicted by neonatal procedural pain and thalamic development.

METHODS

In a prospective longitudinal cohort study, N = 140 very preterm infants (median GA at birth 28 weeks) underwent MRI early-in-life and again at term-equivalent age. Children returned for assessment at 4.5 years. Parents reported on child sensory processing behaviors on the Short Sensory Profile. General linear models were used to assess factors associated with sensory processing behaviors, adjusting for clinical and demographic factors.

RESULTS

Among extremely preterm neonates (born 24-28 weeks' GA), but not very-preterm neonates (29-32 weeks' GA), more invasive procedures were associated with poorer sensory processing (B = -0.09, 95%CI [-0.17, -0.01] p = 0.03). In the overall cohort, fewer sensory processing problems were associated with greater thalamic growth between birth and term-equivalent age (B = 0.3, 95%CI [0.11, 0.42], p < 0.001). Extremely preterm neonates exposed to a high number of skin-breaking procedures who exhibited slower neonatal thalamic growth displayed the highest sensory processing problems (B = -26.2, 95%CI [-45.96, -6.38], p = 0.01).

CONCLUSION

Early exposure to pain and related alterations in the developing thalamus may be a key factor underlying later sensory problems in children born extremely preterm.

Amygdala subnuclei volumes, functional connectivity, and social–emotional outcomes in children born very preterm

Children born very preterm can demonstrate social-cognitive impairments, which may result from limbic system dysfunction. Altered development of the subnuclei of the amygdala, stress-sensitive regions involved in emotional processing, may be key predictors of social-skill development. In a prospective cohort study, 7-year-old children born very preterm underwent neurodevelopmental testing and brain MRI. The Child Behavioral Checklist was used to assess social–emotional outcomes. Subnuclei volumes were extracted automatically from structural scans (n = 69) and functional connectivity (n = 66) was examined. General Linear Models were employed to examine the relationships between amygdala subnuclei volumes and functional connectivity values and social–emotional outcomes. Sex was a significant predictor of all social–emotional outcomes (P < 0.05), with boys having poorer social–emotional outcomes. Smaller right basal nuclei volumes (B = -0.043, P = 0.014), smaller right cortical volumes (B = -0.242, P = 0.02) and larger right central nuclei volumes (B = 0.85, P = 0.049) were associated with increased social problems. Decreased connectivity strength between thalamic and amygdala networks and smaller right basal volumes were significant predictors of greater social problems (both, P < 0.05), effects which were stronger in girls (P = 0.025). Dysregulated maturation of the amygdala subnuclei, along with altered connectivity strength in stress-sensitive regions, may reflect stress-induced dysfunction and can be predictive of social–emotional outcomes.

Three-Dimensional Atlas of the Human Amygdala Subnuclei Constructed Using Immunohistochemical and Ultrahigh-Field Magnetic Resonance Imaging Data

The amygdala is central for social and emotional processing and has been implicated in various disorders including autism spectrum disorder (ASD) and Alzheimer's disease (AD). Animal research and some limited research with humans has indicated that widespread alterations in neuronal development or neuronal loss in the basolateral and other amygdala subnuclei may be a contributing factor to variations in social behaviours. Yet, the basolateral amygdala is comprised of three subnuclei, each with a specialized role related to the coordination of emotional regulation. Due to their small size, the nuclei which comprise the basolateral amygdala remain understudied in humans in vivo. In this work, we describe methodology to examine the basolateral amygdala and other subnuclei in human ex vivo medial temporal lobe prosections using ultrahigh-field magnetic resonance imaging (MRI) at 9.4 T. Manual segmentations of the amygdala subnuclei on MR images, verified with immunohistochemical data, provide a robust three-dimensional atlas of the human amygdala. The goal is to apply the atlas to in vivo MRI scans to examine basolateral amygdala macrostructural development attributed to social cognitive dysfunction in ASD and other neurodevelopmental disorders. Furthermore, the atlas can be used to examine MRI-based correlates of neuronal loss commonly seen in neurodegenerative disorders.

Early adversity and positive parenting: Association with cognitive outcomes in children with autism spectrum disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impairments in social communication and repetitive behaviors. Children with ASD are statistically more likely to experience early adversity; however, little is known about the types of early adversity that place these children at risk, the role of parenting as a protective factor, and how this early life stress impacts cognitive outcomes. We assessed early adversity in 302 children (ASD = 98) aged 6-16 years old, using parent-based report. To identify protective factors, we assessed parenting styles using parent surveys. Executive functions were assessed in the children using the WISC-V. Children with ASD had an increased incidence of familial stressors compared to the typically developing (TD) group. Positive parenting was associated with a significant decrease in the incidence of familial adverse events for both children with ASD and TD children. Examining the relationship between adversity and cognitive outcomes, in young children (6-11 years) with ASD, environmental stressors were associated with cognitive impairments. Findings suggest children with ASD may be at higher risk for familial adversity than their TD peers. However, all children benefit from positive parenting styles, which may mitigate the adverse effects of family-based early life stress. LAY SUMMARY: Some key features of Autism Spectrum Disorder (ASD) include difficulties with communication and social impairments. This means that children with ASD may be more likely to experience early adversity (stressful social interactions which take place during childhood) than children without ASD. Research in typically developing (TD) children has shown that experiencing more stressful events in childhood can cause changes in the brain, which can potentially impact the child's memory, reasoning, and decision-making skills later in life. However, there is evidence to suggest that having a nurturing relationship with a parent can offset some of the negative impacts of childhood adversity. In our study, we found that children with ASD are more likely to experience family-related stress compared to TD children. Having a positive relationship with a parent, however, was linked to experiencing this type of stress less often for all children, regardless of whether they were diagnosed with ASD. We also found that stressors related to environmental factors like financial instability were associated with lower cognitive abilities in children with ASD under 12 years of age. Understanding how these factors interact and differ in children with ASD can help to build stronger families and help children with ASD to thrive throughout their development.

Depression in pregnant women with and without COVID-19

Evidence suggests that pregnant women who test positive for COVID-19 may develop more severe illness than non-pregnant women and may be at greater risk for psychological distress. The relationship between COVID-19 status (positive, negative, never tested) and symptoms of depression was examined in a survey study (May to September 2020) of pregnant women (n = 869). Pregnant women who reported testing positive for COVID-19 were significantly more likely to report depressive symptoms compared with women who tested negative (P = 0.027) and women who were never tested (P = 0.005). Findings indicate that pregnant women who test positive for COVID-19 should be screened and monitored for depressive symptoms.

Sensory Function and Psychological Factors in Children With Complex Regional Pain Syndrome Type 1

OBJECTIVE

To assess thermal-sensory thresholds and psychosocial factors in children with Complex Regional Pain Syndrome Type 1 (CRPS-I) compared to healthy children.

METHODS

We conducted quantitative sensory testing on 34 children with CRPS-I and 56 pain-free children. Warm, cool, heat, and cold stimuli were applied to the forearm. Children with CRPS-I had the protocol administered to the pain site and the contralateral-pain site. Participants completed the self-report Behavior Assessment System for Children.

RESULTS

Longer pain durations (>5.1 months) were associated with decreased sensitivity to cold pain on the pain site (P = .04). Higher pain-intensity ratings were associated with elevated anxiety scores (P = .03). Anxiety and social stress were associated with warmth sensitivity (both P < .05) on the contralateral-pain site.

CONCLUSIONS

Pain duration is an important factor in assessing pediatric CRPS-I. Hyposensitivity in the affected limb may emerge due to degeneration of nociceptive nerves. Anxiety may contribute to thermal-sensory perception in childhood CRPS-I.

Peer victimization and the association with hippocampal development and working memory in children with ADHD and typically-developing children

The symptoms of hyperactivity-impulsivity and inattention displayed by children with ADHD put them at risk of experiencing peer victimization. Hippocampal maturation, may reduce a child's vulnerability to the experience of peer victimization, as it has been associated with decreased ADHD symptomatology. Working memory is an important executive function in the formation and maintenance of social relationships, which is often impaired in ADHD. We aimed to evaluate the relationship between problem behaviours, peer victimization, hippocampal morphology, and working memory in children with and without ADHD. 218 typically-developing participants (50.5% male) and 232 participants diagnosed with ADHD (77.6% male) were recruited. The ADHD group was subdivided into inattentive (ADHD-I) or combined (ADHD-C) types. The Child Behavior Checklist measured problem behaviours and peer victimization. Children underwent Magnetic Resonance Imaging (MRI). Hippocampal subfield volumes were obtained using FreeSurfer. The Wechsler Intelligence Scale for Children-fifth edition measured working memory (WM). The ADHD-C group displayed significantly higher levels of problem behaviours and peer victimization (all, p < 0.001), compared to the other groups. Left Cornu Ammonis 3 (CA3) volume was a positive predictor of peer victimization (all, p < 0.013). Left CA3 volume was a positive predictor of WM and left Cornu Ammonis 4 (CA4) volume negatively predicted WM (all, p < 0.025). A cluster analysis revealed that children displaying symptoms of hyperactivity-impulsivity are the most at risk for peer victimization. Interventions focusing on minimizing peer victimization may aid in mitigating adverse downstream effects, and assist in promoting brain health and cognitive function.

Amygdala subnuclei development in adolescents with autism spectrum disorder: Association with social communication and repetitive behaviors

INTRODUCTION

The amygdala subnuclei regulate emotional processing and are widely implicated in social cognitive impairments often seen in children with autism spectrum disorder (ASD). Dysregulated amygdala development has been reported in young children with ASD; less is known about amygdala maturation in later adolescence, a sensitive window for social skill development.

METHODS

The macrostructural development of the amygdala subnuclei was assessed at two time points in a longitudinal magnetic resonance imaging (MRI) study of adolescents with ASD (n = 23) and typically-developing adolescents (n = 15) . In adolescents with ASD, amygdala subnuclei growth was assessed in relation to ASD symptomatology based on standardized diagnostic assessments. Participants were scanned with MRI at median age of 12 years and returned for a second scan at a median age of 15 years. The volumes of nine amygdala subnuclei were extracted using an automatic segmentation algorithm.

RESULTS

When examining the longitudinal data acquired across two time points, adolescents with ASD had larger basolateral amygdala (BLA) nuclei volumes compared to typically developing adolescents (B = 46.8, p = 0.04). When examining ASD symptomatology in relation to the growth of the amygdala subnuclei, reciprocal social interaction scores on the ADI-R were positively associated with increased growth of the BLA nuclei (B = 8.3, p < 0.001). Growth in the medial nucleus negatively predicted the communication (B = -46.9, p = 0.02) and social (B = -47.7, p < 0.001) domains on the ADOS-G. Growth in the right cortical nucleus (B = 26.14, p = 0.02) positively predicted ADOS-G social scores. Central nucleus maturation (B = 29.9, p = 0.02) was associated with the repetitive behaviors domain on the ADOS-G.

CONCLUSIONS

Larger BLA volumes in adolescents with ASD may reflect underlying alterations in cellular density previously reported in post-mortem studies. Furthermore, findings demonstrate an association between regional growth in amygdala subnuclei volumes and ASD symptomatology. Improved understanding of the developmental trajectories of the amygdala subnuclei may aid in identifying key windows for interventions, particularly for social communication, in adolescents with ASD.

Early protein intake predicts functional connectivity and neurocognition in preterm born children

Nutritional intake can promote early neonatal brain development in very preterm born neonates (< 32 weeks’ gestation). In a group of 7-year-old very preterm born children followed since birth, we examined whether early nutrient intake in the first weeks of life would be associated with long-term brain function and neurocognitive skills at school age. Children underwent resting-state functional MRI (fMRI), intelligence testing (Wechsler Intelligence Scale for Children, 5th Ed) and visual-motor processing (Beery-Buktenica, 5th Ed) at 7 years. Relationships were assessed between neonatal macronutrient intakes, functional connectivity strength between thalamic and default mode networks (DMN), and neuro-cognitive function using multivariable regression. Greater functional connectivity strength between thalamic networks and DMN was associated with greater intake of protein in the first week (β = 0.17; 95% CI 0.11, 0.23, p < 0.001) but lower intakes of fat (β = − 0.06; 95% CI − 0.09, − 0.02, p = 0.001) and carbohydrates (β = − 0.03; 95% CI − 0.04, − 0.01, p = 0.003). Connectivity strength was also associated with protein intake during the first month (β = 0.22; 95% CI 0.06, 0.37, p = 0.006). Importantly, greater thalamic-DMN connectivity strength was associated with higher processing speed indices (β = 26.9; 95% CI 4.21, 49.49, p = 0.02) and visual processing scores (β = 9.03; 95% CI 2.27, 15.79, p = 0.009). Optimizing early protein intake may contribute to promoting long-term brain health in preterm-born children.

Association of early skin breaks and neonatal thalamic maturation: A modifiable risk?

OBJECTIVE

To test the hypothesis that a strategy of prolonged arterial line (AL) and central venous line (CVL) use is associated with reduced neonatal invasive procedures and improved growth of the thalamus in extremely preterm neonates (<28 weeks' gestation).

METHODS

Two international cohorts of very preterm neonates (n = 143) with prolonged (≥14 days) or restricted (<14 days) use of AL/CVL were scanned serially with MRI. General linear models were used to determine the association between skin breaks and thalamic volumes, accounting for clinical confounders and site differences. Children were assessed at preschool age on standardized tests of motor and cognitive function. Outcome scores were assessed in relation to neonatal thalamic growth.

RESULTS

Prolonged AL/CVL use in neonates (n = 86) was associated with fewer skin breaks (median 34) during the hospital stay compared to restricted AL/CVL use (n = 57, median 91, 95% confidence interval [CI] 60.35-84.89). Neonates with prolonged AL/CVL use with fewer skin breaks had significantly larger thalamic volumes early in life compared to neonates with restricted line use (B = 121.8, p = 0.001, 95% CI 48.48-195.11). Neonatal thalamic growth predicted preschool-age cognitive (B = 0.001, 95% CI 0.0003-0.001, p = 0.002) and motor scores (B = 0.01, 95% CI 0.001-0.10, p = 0.02). Prolonged AL/CVL use was not associated with greater incidence of sepsis or multiple infections.

CONCLUSIONS

Prolonged AL/CVL use in preterm neonates may provide an unprecedented opportunity to reduce invasive procedures in preterm neonates. Pain reduction in very preterm neonates is associated with optimal thalamic growth and neurodevelopment.

Can you see what I see? Assessing brain maturation and injury in preterm and term neonates

This scientific commentary refers to ‘Modelling brain development to detect white matter injury in term and preterm born neonates’ by O’Muircheartaigh et al. (doi: 10.1093/brain/awz412).

Sex-Based Differences in Cortical and Subcortical Development in 436 Individuals Aged 4-54 Years

Sex-based differences in brain development have long been established in ex vivo studies. Recent in vivo studies using magnetic resonance imaging (MRI) have offered considerable insight into sex-based variations in brain maturation. However, reports of sex-based differences in cortical volumes and thickness are inconsistent. We examined brain maturation in a cross-sectional, single-site cohort of 436 individuals (201 [46%] males) aged 4-54 years (median = 16 years). Cortical thickness, cortical surface area, subcortical surface area, volumes of the cerebral cortex, white matter (WM), cortical and subcortical gray matter (GM), including the thalamic subnuclei, basal ganglia, and hippocampi were calculated using automatic segmentation pipelines. Subcortical structures demonstrated distinct curvilinear trajectories from the cortex, in both volumetric maturation and surface-area expansion in relation to age. Surface-area analysis indicated that dorsal regions of the thalamus, globus pallidus and striatum, regions demonstrating structural connectivity with frontoparietal cortices, exhibited extensive expansion with age, and were inversely related to changes seen in cortical maturation, which contracted with age. Furthermore, surface-area expansion was more robust in males in comparison to females. Age- and sex-related maturational changes may reflect alterations in dendritic and synaptic architecture known to occur during development from early childhood through to mid-adulthood.

Converging function, structure, and behavioural features of emotion regulation in very preterm children

Children born very preterm (VPT; <32 weeks' gestational age) are at high risk for emotional regulation and social communication impairments. However, the underlying neurobiological correlates of these difficulties remain poorly understood. Using a multimodal approach, including both magnetoencephalographic and structural magnetic resonance imaging, we investigated the functional, structural, and behavioural characteristics of socio-emotional processing in 19 school-age children born VPT and 21 age-matched term-born (TB) children (7-13 years). Structural MRI analyses were conducted on a subset of these groups (16 VPT and 21 age-matched TB). Results showed that the inhibition of aversive socio-emotional stimuli was associated with a sustained reduction of right frontoparietal functional brain activity in children born VPT children. Moreover, whole brain structural analyses showed that reductions of cortical thickness or volume in these regions were associated with poor socio-emotional performance in children born VPT. Hence, our results suggest that functional and structural alterations encompassing the frontoparietal areas might be a biological marker of less efficient emotion regulation processes/performance in school-age children born VPT. These findings open up novel avenues to investigate the potential impact of such atypicalities, and in particular, those related to the atypical maturation of the medial prefrontal regions, on the frequent development of psychiatric disorders in this vulnerable population.

White matter injury in term neonates with congenital heart diseases: Topology & comparison with preterm newborns

BACKGROUND

Neonates with congenital heart disease (CHD) are at high risk of punctate white matter injury (WMI) and impaired brain development. We hypothesized that WMI in CHD neonates occurs in a characteristic distribution that shares topology with preterm WMI and that lower birth gestational age (GA) is associated with larger WMI volume.

OBJECTIVE

(1) To quantitatively assess the volume and location of WMI in CHD neonates across three centres. (2) To compare the volume and spatial distribution of WMI between term CHD neonates and preterm neonates using lesion mapping.

METHODS

In 216 term born CHD neonates from three prospective cohorts (mean birth GA: 39 weeks), WMI was identified in 86 neonates (UBC: 29; UCSF: 43; UCZ: 14) on pre- and/or post-operative T1 weighted MRI. WMI was manually segmented and volumes were calculated. A standard brain template was generated. Probabilistic WMI maps (total, pre- and post-operative) were developed in this common space. Using these maps, WMI in the term CHD neonates was compared with that in preterm neonates: 58 at early-in-life (mean postmenstrual age at scan 32.2 weeks); 41 at term-equivalent age (mean postmenstrual age at scan 40.1 weeks).

RESULTS

The total WMI volumes of CHD neonates across centres did not differ (p = 0.068): UBC (median = 84.6 mm³, IQR = 26-174.7 mm³); UCSF (median = 104 mm³, IQR = 44-243 mm³); UCZ (median = 121 mm³, IQR = 68-200.8 mm³). The spatial distribution of WMI in CHD neonates showed strong concordance across centres with predilection for anterior and posterior rather than central lesions. Predominance of anterior lesions was apparent on the post-operative WMI map relative to the pre-operative map. Lower GA at birth predicted an increasing volume of WMI across the full cohort (41.1 mm³ increase of WMI per week decrease in gestational age; 95% CI 11.5-70.8; p = 0.007), when accounting for centre and heart lesion. While WMI in term CHD and preterm neonates occurs most commonly in the intermediate zone/outer subventricular zone there is a paucity of central lesions in the CHD neonates relative to preterms.

CONCLUSIONS

WMI in term neonates with CHD occurs in a characteristic topology. The spatial distribution of WMI in term neonates with CHD reflects the expected maturation of pre-oligodendrocytes such that the central regions are less vulnerable than in the preterm neonates.

Nutrient Intake in the First Two Weeks of Life and Brain Growth in Preterm Neonates

BACKGROUND

Optimizing early nutritional intake in preterm neonates may promote brain health and neurodevelopment through enhanced brain maturation. Our objectives were (1) to determine the association of energy and macronutrient intake in the first 2 weeks of life with regional and total brain growth and white matter (WM) maturation, assessed by 3 serial MRI scans in preterm neonates; (2) to examine how critical illness modifies this association; and (3) to investigate the relationship with neurodevelopmental outcomes.

METHODS

Forty-nine preterm neonates (21 boys, median [interquartile range] gestational age: 27.6 [2.3] weeks) were scanned serially at the following median postmenstrual weeks: 29.4, 31.7, and 41. The total brain, basal nuclei, and cerebellum were semiautomatically segmented. Fractional anisotropy was extracted from diffusion tensor imaging data. Nutritional intake from day of life 1 to 14 was monitored and clinical factors were collected.

RESULTS

Greater energy and lipid intake predicted increased total brain and basal nuclei volumes over the course of neonatal care to term-equivalent age. Similarly, energy and lipid intake were significantly associated with fractional anisotropy values in selected WM tracts. The association of ventilation duration with smaller brain volumes was attenuated by higher energy intake. Brain growth predicted psychomotor outcome at 18 months' corrected age.

CONCLUSIONS

In preterm neonates, greater energy and enteral feeding during the first 2 weeks of life predicted more robust brain growth and accelerated WM maturation. The long-lasting effect of early nutrition on neurodevelopment may be mediated by enhanced brain growth. Optimizing nutrition in preterm neonates may represent a potential avenue to mitigate the adverse brain health consequences of critical illness.

Clinical Risk Factors for Punctate White Matter Lesions on Early Magnetic Resonance Imaging in Preterm Newborns

OBJECTIVE

To identify clinical risk factors for punctate white matter lesions (PWML) on early magnetic resonance imaging (MRI) in 2 cohorts of newborns born extremely preterm in different neonatal centers.

STUDY DESIGN

A total of 250 newborns born preterm at less than 28 weeks of gestation (mean 26.4 ± 1.1 weeks) with an early MRI were identified from 2 neonatal centers, in Vancouver, Canada (cohort A, n = 100) and Utrecht, the Netherlands (cohort B, n = 150). Cohort A was imaged as part of a prospective research study and cohort B was imaged as part of routine clinical care. PWML were defined as cluster type foci of hyperintensity on T1-weighted imaging and were identified at a mean postmenstrual age of 31.1 (±1.9) weeks. Multivariable analysis was used to identify clinical factors predictive of PWML.

RESULTS

Cluster type PWML were found in 47 newborns born extremely preterm (18.8%) and were more common in cohort A (32%) than in cohort B (10%). Newborns in cohort A generally were sicker than those in cohort B. Multivariable analyses revealed that greater birth weight (B = 0.002; P < .02), grade II-III intraventricular hemorrhage (B = 0.83; P < .02), and cohort A (B = 1.34; P < .0001) were independent predictors of PWML.

CONCLUSION

Several risk factors for PWML on early MRI were identified. The interaction among birth weight, intraventricular hemorrhage, and other aspects of postnatal illness as risk factors for PWML warrants further investigation in newborns born extremely preterm and may help to identify modifiable risk factors for PWML.

Quantitative assessment of white matter injury in preterm neonates: Association with outcomes

OBJECTIVE

To quantitatively assess white matter injury (WMI) volume and location in very preterm neonates, and to examine the association of lesion volume and location with 18-month neurodevelopmental outcomes.

METHODS

Volume and location of WMI was quantified on MRI in 216 neonates (median gestational age 27.9 weeks) who had motor, cognitive, and language assessments at 18 months corrected age (CA). Neonates were scanned at 32.1 postmenstrual weeks (median) and 68 (31.5%) had WMI; of 66 survivors, 58 (87.9%) had MRI and 18-month outcomes. WMI was manually segmented and transformed into a common image space, accounting for intersubject anatomical variability. Probability maps describing the likelihood of a lesion predicting adverse 18-month outcomes were developed.

RESULTS

WMI occurs in a characteristic topology, with most lesions occurring in the periventricular central region, followed by posterior and frontal regions. Irrespective of lesion location, greater WMI volumes predicted poor motor outcomes (p = 0.001). Lobar regional analysis revealed that greater WMI volumes in frontal, parietal, and temporal lobes have adverse motor outcomes (all, p < 0.05), but only frontal WMI volumes predicted adverse cognitive outcomes (p = 0.002). To account for lesion location and volume, voxel-wise odds ratio (OR) maps demonstrate that frontal lobe lesions predict adverse cognitive and language development, with maximum odds ratios (ORs) of 78.9 and 17.5, respectively, while adverse motor outcomes are predicted by widespread injury, with maximum OR of 63.8.

CONCLUSIONS

The predictive value of frontal lobe WMI volume highlights the importance of lesion location when considering the neurodevelopmental significance of WMI. Frontal lobe lesions are of particular concern.

Neural Correlates of Reward Processing in Typical and Atypical Development

Atypically developing children including those born preterm or who have autism spectrum disorder can display difficulties with evaluating rewarding stimuli, which may result from impaired maturation of reward and cognitive control brain regions. During functional magnetic resonance imaging, 58 typically and atypically developing children (6-12 years) participated in a set-shifting task that included the presentation of monetary reward stimuli. In typically developing children, reward stimuli were associated with age-related increases in activation in cognitive control centers, with weaker changes in reward regions. In atypically developing children, no age-related changes were evident. Maturational disturbances in the frontostriatal regions during atypical development may underlie task-based differences in activation.

Interplay of brain structure and function in neonatal congenital heart disease

Objective

To evaluate whether structural and microstructural brain abnormalities in neonates with congenital heart disease (CHD) correlate with neuronal network dysfunction measured by analysis of EEG connectivity.

Methods

We studied a prospective cohort of 20 neonates with CHD who underwent continuous EEG monitoring before surgery to assess functional brain maturation and network connectivity, structural magnetic resonance imaging (MRI) to determine the presence of brain injury and structural brain development, and diffusion tensor MRI to assess brain microstructural development.

Results

Neonates with MRI brain injury and delayed structural and microstructural brain development demonstrated significantly stronger high‐frequency (beta and gamma frequency band) connectivity. Furthermore, neonates with delayed microstructural brain development demonstrated significantly weaker low‐frequency (delta, theta, alpha frequency band) connectivity. Neonates with brain injury also displayed delayed functional maturation of EEG background activity, characterized by greater background discontinuity.

Interpretation

These data provide new evidence that early structural and microstructural developmental brain abnormalities can have immediate functional consequences that manifest as characteristic alterations of neuronal network connectivity. Such early perturbations of developing neuronal networks, if sustained, may be responsible for the persistent neurocognitive impairment prevalent in adolescent survivors of CHD. These foundational insights into the complex interplay between evolving brain structure and function may have relevance for a wide spectrum of neurological disorders manifesting early developmental brain injury.

Manual-Protocol Inspired Technique for Improving Automated MR Image Segmentation during Label Fusion

Recent advances in multi-atlas based algorithms address many of the previous limitations in model-based and probabilistic segmentation methods. However, at the label fusion stage, a majority of algorithms focus primarily on optimizing weight-maps associated with the atlas library based on a theoretical objective function that approximates the segmentation error. In contrast, we propose a novel method—Autocorrecting Walks over Localized Markov Random Fields (AWoL-MRF)—that aims at mimicking the sequential process of manual segmentation, which is the gold-standard for virtually all the segmentation methods. AWoL-MRF begins with a set of candidate labels generated by a multi-atlas segmentation pipeline as an initial label distribution and refines low confidence regions based on a localized Markov random field (L-MRF) model using a novel sequential inference process (walks). We show that AWoL-MRF produces state-of-the-art results with superior accuracy and robustness with a small atlas library compared to existing methods. We validate the proposed approach by performing hippocampal segmentations on three independent datasets: (1) Alzheimer's Disease Neuroimaging Database (ADNI); (2) First Episode Psychosis patient cohort; and (3) A cohort of preterm neonates scanned early in life and at term-equivalent age. We assess the improvement in the performance qualitatively as well as quantitatively by comparing AWoL-MRF with majority vote, STAPLE, and Joint Label Fusion methods. AWoL-MRF reaches a maximum accuracy of 0.881 (dataset 1), 0.897 (dataset 2), and 0.807 (dataset 3) based on Dice similarity coefficient metric, offering significant performance improvements with a smaller atlas library (< 10) over compared methods. We also evaluate the diagnostic utility of AWoL-MRF by analyzing the volume differences per disease category in the ADNI1: Complete Screening dataset. We have made the source code for AWoL-MRF public at: https://github.com/CobraLab/AWoL-MRF.

Maternal Postsecondary Education Associated With Improved Cerebellar Growth After Preterm Birth

The preterm cerebellum is vulnerable to impaired development impacting long-term outcome. Preterm newborns (<32 weeks) underwent serial magnetic resonance imaging (MRI) scans. The association between parental education and cerebellar volume at each time point was assessed, adjusting for age at scan. In 26 infants, cerebellar volumes at term (P = .001), but not birth (P = .4), were associated with 2-year volumes. For 1 cm(3) smaller cerebellar volume (4% total volume) at term, the cerebellum was 3.18 cm(3) smaller (3% total volume) by 2 years. Maternal postsecondary education was not associated with cerebellar volume at term (P = .16). Maternal postsecondary education was a significant confounder in the relationship between term and 2-year cerebellar volumes (P = .016), with higher education associated with improved volumes by 2 years. Although preterm birth has been found to be associated with smaller cerebellar volumes at term, maternal postsecondary education is associated with improved growth detectable by 2 years.

Automatic segmentation of the hippocampus for preterm neonates from early-in-life to term-equivalent age

Introduction

The hippocampus, a medial temporal lobe structure central to learning and memory, is particularly vulnerable in preterm-born neonates. To date, segmentation of the hippocampus for preterm-born neonates has not yet been performed early-in-life (shortly after birth when clinically stable). The present study focuses on the development and validation of an automatic segmentation protocol that is based on the MAGeT-Brain (Multiple Automatically Generated Templates) algorithm to delineate the hippocampi of preterm neonates on their brain MRIs acquired at not only term-equivalent age but also early-in-life.

Methods

First, we present a three-step manual segmentation protocol to delineate the hippocampus for preterm neonates and apply this protocol on 22 early-in-life and 22 term images. These manual segmentations are considered the gold standard in assessing the automatic segmentations. MAGeT-Brain, automatic hippocampal segmentation pipeline, requires only a small number of input atlases and reduces the registration and resampling errors by employing an intermediate template library. We assess the segmentation accuracy of MAGeT-Brain in three validation studies, evaluate the hippocampal growth from early-in-life to term-equivalent age, and study the effect of preterm birth on the hippocampal volume. The first experiment thoroughly validates MAGeT-Brain segmentation in three sets of 10-fold Monte Carlo cross-validation (MCCV) analyses with 187 different groups of input atlases and templates. The second experiment segments the neonatal hippocampi on 168 early-in-life and 154 term images and evaluates the hippocampal growth rate of 125 infants from early-in-life to term-equivalent age. The third experiment analyzes the effect of gestational age (GA) at birth on the average hippocampal volume at early-in-life and term-equivalent age using linear regression.

Results

The final segmentations demonstrate that MAGeT-Brain consistently provides accurate segmentations in comparison to manually derived gold standards (mean Dice's Kappa > 0.79 and Euclidean distance <1.3 mm between centroids). Using this method, we demonstrate that the average volume of the hippocampus is significantly different (p < 0.0001) in early-in-life (621.8 mm³) and term-equivalent age (958.8 mm³). Using these differences, we generalize the hippocampal growth rate to 38.3 ± 11.7 mm³/week and 40.5 ± 12.9 mm³/week for the left and right hippocampi respectively. Not surprisingly, younger gestational age at birth is associated with smaller volumes of the hippocampi (p = 0.001).

Conclusions

MAGeT-Brain is capable of segmenting hippocampi accurately in preterm neonates, even at early-in-life. Hippocampal asymmetry with a larger right side is demonstrated on early-in-life images, suggesting that this phenomenon has its onset in the 3rd trimester of gestation. Hippocampal volume assessed at the time of early-in-life and term-equivalent age is linearly associated with GA at birth, whereby smaller volumes are associated with earlier birth.

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We develop a MAGeT-Brain based automatic protocol to segment hippocampus in preterm neonates.

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MAGeT-Brain can accurately segment hippocampus in preterm neonates, even at early-in-life.

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Hippocampal asymmetry with a larger right side is demonstrated on early-in-life images.

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Smaller hippocampal volumes are associated with earlier birth in preterm neonates.

Tract-Based Spatial Statistics in Preterm-Born Neonates Predicts Cognitive and Motor Outcomes at 18 Months

BACKGROUND AND PURPOSE

Adverse neurodevelopmental outcome is common in children born preterm. Early sensitive predictors of neurodevelopmental outcome such as MR imaging are needed. Tract-based spatial statistics, a diffusion MR imaging analysis method, performed at term-equivalent age (40 weeks) is a promising predictor of neurodevelopmental outcomes in children born very preterm. We sought to determine the association of tract-based spatial statistics findings before term-equivalent age with neurodevelopmental outcome at 18-months corrected age.

MATERIALS AND METHODS

Of 180 neonates (born at 24-32-weeks' gestation) enrolled, 153 had DTI acquired early at 32 weeks' postmenstrual age and 105 had DTI acquired later at 39.6 weeks' postmenstrual age. Voxelwise statistics were calculated by performing tract-based spatial statistics on DTI that was aligned to age-appropriate templates. At 18-month corrected age, 166 neonates underwent neurodevelopmental assessment by using the Bayley Scales of Infant Development, 3rd ed, and the Peabody Developmental Motor Scales, 2nd ed.

RESULTS

Tract-based spatial statistics analysis applied to early-acquired scans (postmenstrual age of 30-33 weeks) indicated a limited significant positive association between motor skills and axial diffusivity and radial diffusivity values in the corpus callosum, internal and external/extreme capsules, and midbrain (P < .05, corrected). In contrast, for term scans (postmenstrual age of 37-41 weeks), tract-based spatial statistics analysis showed a significant relationship between both motor and cognitive scores with fractional anisotropy in the corpus callosum and corticospinal tracts (P < .05, corrected). Tract-based spatial statistics in a limited subset of neonates (n = 22) scanned at <30 weeks did not significantly predict neurodevelopmental outcomes.

CONCLUSIONS

The strength of the association between fractional anisotropy values and neurodevelopmental outcome scores increased from early-to-late-acquired scans in preterm-born neonates, consistent with brain dysmaturation in this population.

Stochastic process for white matter injury detection in preterm neonates

Preterm births are rising in Canada and worldwide. As clinicians strive to identify preterm neonates at greatest risk of significant developmental or motor problems, accurate predictive tools are required. Infants at highest risk will be able to receive early developmental interventions, and will also enable clinicians to implement and evaluate new methods to improve outcomes. While severe white matter injury (WMI) is associated with adverse developmental outcome, more subtle injuries are difficult to identify and the association with later impairments remains unknown. Thus, our goal was to develop an automated method for detection and visualization of brain abnormalities in MR images acquired in very preterm born neonates. We have developed a technique to detect WMI in T1-weighted images acquired in 177 very preterm born infants (24–32 weeks gestation). Our approach uses a stochastic process that estimates the likelihood of intensity variations in nearby pixels; with small variations being more likely than large variations. We first detect the boundaries between normal and injured regions of the white matter. Following this we use a measure of pixel similarity to identify WMI regions. Our algorithm is able to detect WMI in all of the images in the ground truth dataset with some false positives in situations where the white matter region is not segmented accurately.