Publications by authors named "Sein J"

In the past decade, noble gases have emerged as highly promising neuroprotective agents. Previous studies have demonstrated the efficacy of argon neuroprotection in rodent models of cerebral ischemia. The objective of the present pre-clinical study was to confirm the neuroprotective effect of argon in a non-human primate model of endovascular ischemic stroke.

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Recent efforts to chart human brain growth across the lifespan using large-scale MRI data have provided reference standards for human brain development. However, similar models for nonhuman primate (NHP) growth are lacking. The rhesus macaque, a widely used NHP in translational neuroscience due to its similarities in brain anatomy, phylogenetics, cognitive, and social behaviors to humans, serves as an ideal NHP model.

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In a functional magnetic resonance imaging study, we examined speech error monitoring in a cortico-cerebellar network for two contrasts: (a) correct trials with high versus low articulatory error probability and (b) overtly committed errors versus correct trials. Engagement of the cognitive cerebellar region Crus I in both contrasts suggests that this region is involved in overarching performance monitoring. The activation of cerebellar motor regions (superior medial cerebellum, lobules VI and VIII) indicates the additional presence of a sensorimotor driven implementation of control.

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What is the function of auditory hemispheric asymmetry? We propose that the identification of sound sources relies on the asymmetric processing of two complementary and perceptually relevant acoustic invariants: actions and objects. In a large dataset of environmental sounds, we observed that temporal and spectral modulations display only weak covariation. We then synthesized auditory stimuli by simulating various actions (frictions) occurring on different objects (solid surfaces).

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Addictions often develop in a social context, although the influence of social factors did not receive much attention in the neuroscience of addiction. Recent animal studies suggest that peer presence can reduce cocaine intake, an influence potentially mediated, among others, by the subthalamic nucleus (STN). However, there is to date no neurobiological study investigating this mediation in humans.

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Article Synopsis
  • The planum temporale (PT) area in the left hemisphere is crucial for language development and is found to be asymmetrical in both humans and newborn baboons, indicating a possible pre-wired language readiness in the brain.
  • Research showed that 27 newborn baboons with a larger left PT were more likely to develop right-handed communication gestures as they matured, suggesting a link between early brain structure and future communicative behavior.
  • This study implies that PT asymmetry might represent an evolutionary trait that underlies shared gestural communication in both monkeys and humans.
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Texture, a fundamental object attribute, is perceived through multisensory information including touch and auditory cues. Coherent perceptions may rely on shared texture representations across different senses in the brain. To test this hypothesis, we delivered haptic textures coupled with a sound synthesizer to generate real-time textural sounds.

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Biscriptuality is the ability to read and write using two scripts. Despite the increasing number of biscripters, this phenomenon remains poorly understood. Here, we focused on investigating graphomotor processing in French-Arabic biscripters.

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The left ventral occipito-temporal cortex (left-vOT) plays a key role in reading. Interestingly, the area also responds to speech input, suggesting that it may have other functions beyond written word recognition. Here, we adopt graph theoretical analysis to investigate the left-vOT's functional role in the whole-brain network while participants process spoken sentences in different contexts.

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Article Synopsis
  • - The human action observation network (AON) in the brain is responsible for processing observed actions and is present from childhood, but its sensitivity to social versus object-related actions may differ between adolescents and adults.
  • - A study using fMRI scanned teenagers and adults while they watched videos of actions differing in sociality and transitivity, revealing that both groups engaged similar brain areas; however, adolescents showed lower accuracy in processing these actions.
  • - The results suggest that adolescent representation of social actions in the AON is less robust compared to adults, indicating ongoing development in how individuals understand social interactions.
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Introduction: The aim of this study was to determine symptom-level risk factors for retinal tear/retinal detachment (RT/RD) in our patients presenting with symptoms of posterior vitreous detachment (PVD).

Methods: We conducted a prospective cohort study of patients presenting to outpatient ophthalmology clinics at a single academic institution with complaint(s) of flashes, floaters, and/or subjective field loss (SFL). Patients received a standardized questionnaire regarding past ocular history and symptom characteristics including number, duration, and timing of flashes and floaters, prior to dilated ocular examination.

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Background: Studying brain processes underlying tactile perception induced by natural-like stimulation is challenging yet crucial to closely match real-world situations.

New Method: We developed a computer-controlled pneumatic device that allows the delivery of complex airflow patterns on subject's body, through a MR-compatible system fixed on an independent clippable mounting device. The intensity of stimulation as well as the timing of each of the four air channels are completely programmable and independent, allowing the precise control and modularity of the airflow delivery.

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How the evolution of speech has transformed the human auditory cortex compared to other primates remains largely unknown. While primary auditory cortex is organized largely similarly in humans and macaques, the picture is much less clear at higher levels of the anterior auditory pathway, particularly regarding the processing of conspecific vocalizations (CVs). A "voice region" similar to the human voice-selective areas has been identified in the macaque right anterior temporal lobe with functional MRI; however, its anatomical localization, seemingly inconsistent with that of the human temporal voice areas (TVAs), has suggested a "repositioning of the voice area" in recent human evolution.

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An event-related functional magnetic resonance imaging study examined how speakers inspect their own speech for errors. Concretely, we sought to assess 1) the role of the temporal cortex in monitoring speech errors, linked with comprehension-based monitoring; 2) the involvement of the cerebellum in internal and external monitoring, linked with forward modeling; and 3) the role of the medial frontal cortex for internal monitoring, linked with conflict-based monitoring. In a word production task priming speech errors, we observed enhanced involvement of the right posterior cerebellum for trials that were correct, but on which participants were more likely to make a word as compared with a nonword error (contrast of internal monitoring).

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The Planum temporale (PT) is one of the key hubs of the language network in the human brain. The gross asymmetry of this perisylvian region toward the left brain was considered as the most emblematic marker of hemispheric specialization of language processes in the brain. Interestingly, this neuroanatomical signature was documented also in newborn infants and preterms, suggesting the early brain's readiness for language acquisition.

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Purpose: Differing techniques have been reported for focal laser therapy for patients with small and medium retinoblastoma. We report the technique used at our center; and report the functional and anatomical outcomes for small and medium retinoblastomas treated with focal laser therapy with or without systemic chemotherapy.

Methods: A retrospective case study was conducted including pediatric patients with macular retinoblastoma treated with systemic chemotherapy and laser ablation from July 1990 to July 2015 at Washington University School of Medicine/Saint Louis Children's Hospital.

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Background: Recently, pioneering expression quantitative trait loci (eQTL) studies on single cell RNA sequencing (scRNA-seq) data have revealed new and cell-specific regulatory single nucleotide variants (SNVs). Here, we present an alternative QTL-related approach applicable to transcribed SNV loci from scRNA-seq data: scReQTL. ScReQTL uses Variant Allele Fraction (VAF) at expressed biallelic loci, and corelates it to gene expression from the corresponding cell.

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The "language-ready" brain theory suggests that the infant brain is pre-wired for language acquisition prior to language exposure. As a potential brain marker of such a language readiness, a leftward structural brain asymmetry was found in human infants for the Planum Temporale (PT), which overlaps with Wernicke's area. In the present longitudinal in vivo MRI study conducted in 35 newborn monkeys (Papio anubis), we found a similar leftward PT surface asymmetry.

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Neuroimaging non-human primates (NHPs) is a growing, yet highly specialized field of neuroscience. Resources that were primarily developed for human neuroimaging often need to be significantly adapted for use with NHPs or other animals, which has led to an abundance of custom, in-house solutions. In recent years, the global NHP neuroimaging community has made significant efforts to transform the field towards more open and collaborative practices.

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Brain vascular damage accumulate in aging and often manifest as white matter hyperintensities (WMHs) on MRI. Despite increased interest in automated methods to segment WMHs, a gold standard has not been achieved and their longitudinal reproducibility has been poorly investigated. The aim of present work is to evaluate accuracy and reproducibility of two freely available segmentation algorithms.

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While the brain network supporting handwriting has previously been defined in adults, its organization in children has never been investigated. We compared the handwriting network of 23 adults and 42 children (8- to 11-year-old). Participants were instructed to write the alphabet, the days of the week, and to draw loops while being scanned.

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There is a growing interest in understanding functional brain decline with aging. The dataset provides raw anatomical and functional images recorded in a group of 20 young volunteers and in another group of 19 older volunteers during a 10-minute period of resting state followed by four consecutive task-related runs. During each task-related run, the participants were exposed to two types of sensory stimulation: a tactile stimulation consisting in a textured-disk rotation under the palm of their right hand or a muscle proprioceptive stimulation consisting in a mechanical vibration applied to the muscle tendon of their wrist abductor.

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Article Synopsis
  • - This study explored age-related changes in how the brain processes sensory information about self-motion, using fMRI to create illusions of hand movements through tactile and proprioceptive stimulation.
  • - Results indicated that while younger and older adults showed similar brain activations during these illusions, older adults had less deactivation in specific frontal brain regions and exhibited a more evenly distributed activity pattern in the sensorimotor areas.
  • - The findings suggest that older individuals experience a decline in proprioceptive perception linked to aging, potentially due to weakened inhibitory brain processes, but they may benefit from improved connectivity between different brain networks.
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Background: The amygdala and the hippocampus are two limbic structures that play a critical role in cognition and behavior, however their manual segmentation and that of their smaller nuclei/subfields in multicenter datasets is time consuming and difficult due to the low contrast of standard MRI. Here, we assessed the reliability of the automated segmentation of amygdalar nuclei and hippocampal subfields across sites and vendors using FreeSurfer in two independent cohorts of older and younger healthy adults.

Methods: Sixty-five healthy older (cohort 1) and 68 younger subjects (cohort 2), from the PharmaCog and CoRR consortia, underwent repeated 3D-T1 MRI (interval 1-90 days).

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With the recent advances in single-cell RNA-sequencing (scRNA-seq) technologies, the estimation of allele expression from single cells is becoming increasingly reliable. Allele expression is both quantitative and dynamic and is an essential component of the genomic interactome. Here, we systematically estimate the allele expression from heterozygous single nucleotide variant (SNV) loci using scRNA-seq data generated on the 10×Genomics Chromium platform.

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