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Polanczyk, G. V.

Publications and source records attributed to Polanczyk, G. V..

4 recordsLinked to original sources

Growth charts of infant visual neurodevelopment generalize across global contexts

Normative brain growth charts in early life hold great promise for furthering basic and clinical science. We leverage the rapid, substantial development of visual cortex function that is indexed by visual-evoked potentials (VEP) in electroencephalography to create longitudinal normative growth curves of task-related brain function with 1374 observations contributed by 802 infants (57 to 579 days old) from South Africa, Brazil, and the United States. Site-specific models were cross-validated and showed excellent fits to other sites samples, demonstrating functional growth curves generalize across contexts robustly. Deviations from the normative growth models associated with early environmental and behavioral measures such as prenatal exposures and postnatal cognition. These findings demonstrate the utility of using functional growth charts to understand and potentially act on individual neurodevelopmental trajectories. VEP brain function growth charts represent a new direction for EEG research to support healthy brain development globally.

neuroscience↗

Spatiotemporal dynamics of EEG microstate networks over the first two years of life: A multi-cohort longitudinal study

The first two years of life are marked by rapid development of large-scale brain networks that support emerging cognition and behavior. Magnetic-resonance approaches have revealed much about largescale networks in sleep, but very little is known about functional network dynamics in awake, behaving infants during this period of substantial development. Microstates are brief instances of distinct spatial topographies of largescale neural activity measured with electroencephalography (EEG) that offer a novel approach to studying whole-brain network dynamics at sub-second scale in awake infants by capturing their temporally coherent brain activity. While emerging literature is leveraging microstate dynamics in adults to understand mature largescale network function, developmental trajectories during networks rapid construction in infancy remain uncharacterized. In this study, we leveraged longitudinal resting-state EEG data from 854 infants across two geoculturally diverse cohorts to explore largescale network development through EEG microstates over the first two years of life. We provide evidence for conserved emergence of various network configurations (microstate classes A-G) through infancy across cohorts using data-driven clustering analyses. We also demonstrate significant longitudinal changes in microstate dynamics during this period, characterized by more numerous and more rapid transitions between largescale configurations, especially over early infancy. While patterns of sensory microstate development were largely consistent between cohorts, higher-order cognitive microstates showed context-specific developmental trends. Together these results provide novel insights into how large-scale brain networks functionally develop and organize across the first two years of life.

neuroscience↗

Early life microbial succession in the gut follows common patterns in humans across the globe

Characterizing the dynamics of microbial community succession in the infant gut microbiome is crucial for understanding child health and development, but no normative model currently exists. Here, we estimate child age using gut microbial taxonomic relative abundances from metagenomes, with high temporal resolution ({+/-}3 months) for the first 1.5 years of life. Using 3,154 samples from 1,827 infants across 12 countries, we trained a random forest model, achieving a root mean square error of 2.61 months. We identified key taxonomic predictors of age, including declines in Bifidobacterium spp. and increases in Faecalibacterium prausnitzii and Lachnospiraceae. Microbial succession patterns are conserved across infants from diverse human populations, suggesting universal developmental trajectories. Functional analysis confirmed trends in key microbial genes involved in feeding transitions and dietary exposures. This model provides a normative benchmark of "microbiome age" for assessing early gut maturation that can be used alongside other measures of child development.

microbiology↗

Cognitive performance in children and adolescents at high-risk for obsessive-compulsive disorder

BackgroundCognitive performance has been studied in subclinical obsessive-compulsive (OC) adults and in adults relatives of OCD patients. Meanwhile, no study has been conducted with children under the same conditions. Across a sample with 49 participants, we investigated whether children and adolescents at high-risk (HR) for OCD (n=18) would present an impaired performance on neurocognitive domains compared to healthy controls (HC, n=31), especially in visuoconstructive ability, executive functions, and intellectual efficiency, functions previously associated with OCD. MethodsFor the HR group, we considered the first-degree children relatives of patients with OCD that present obsessive-compulsive symptoms (OCS), but do not meet diagnostic criteria for OCD. Child psychiatric diagnoses were assessed by the Kiddie Schedule for Affective Disorders and Schizophrenia (K-SADS-PL) by experienced and trained psychologists and OCS were measured by Yale-Brown Obsessive-Compulsive Scale (Y-BOCS). ResultsAlthough we did not find differences in the domains previously hypothesized, a Multivariate Analysis of Variance (MANOVA) revealed impairments in processing speed in HR group (p =0.019; F=3.115), and a t-test identified a higher IQ discrepancy in HR group when compared to HC (p =0.030; t =-2.239), and a discrepancy in verbal and non-verbal abilities as in the memory and working memory tasks. ConclusionsOur results suggest that differences in motor and processing speed and in IQ discrepancy are already present and were identified in a non-clinical sample of HR subjects. Further studies should investigate neurocognitive domains as possible predictors of pediatric OCD.

neuroscience↗