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2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 200-203, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33017964

RESUMO

A central question in neuroscience is how the brain processes real-world sensory input. For decades most classical studies focus on carefully controlled artificial stimuli. More recently researchers started to investigate brain activity under more realistic conditions. The main challenge in this setting is the analysis of the complex signals obtained with modern neuroimaging methods in response to natural stimuli. Inter-subject correlations (ISCs) have become a popular paradigm to study brain activation under natural stimulation. The underlying assumption of this analysis is that features of natural stimuli that are perceived and processed by all subjects exposed to the same stimulus result in similar activation patterns across subjects. Higher degrees of realism in stimulation, for instance audiovisual stimulation is more realistic than auditory stimulation, is usually associated with higher ISC values. We can confirm these findings in experiments in which we present a movie stimulus with varying degrees of realism. Extending previous findings we highlight the importance of artifact removal when evaluating ISCs and show that the impact of realism in natural stimulation on ISCs is frequency-dependent. A major challenge associated with this type of analysis is that it can be difficult to attribute the correlation strength to the physiological process of interest. In this study, we demonstrate that ISCs of neural activation as measured by electroencephalogram (EEG) recordings are influenced significantly by non-neural artifacts such as occulograms. Our findings highlight the potential of inter-subject correlations as a biomarker for immersion: If more realistic stimuli consistently lead to higher inter-subject correlations, then inter-subject correlations can serve as a quantitative marker for how engaging audiovisual stimuli are perceived.Clinical relevance- Future research will evaluate if correlation levels among subjects, who are exposed to natural stimuli are affected by neurological diseases such as Alzheimers, Parkinsons, and Schizophrenia among others.


Assuntos
Artefatos , Eletroencefalografia , Estimulação Acústica , Encéfalo , Neuroimagem
3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 948-951, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018141

RESUMO

Functional near-infrared spectroscopy (fNIRS) has the potential to become the next common noninvasive neuroimaging technique for routine clinical use. Compared to the current standard for neuroimaging, functional magnetic resonance imaging (fMRI), fNIRS boasts several advantages which increase its likelihood for clinical adoption. However, fNIRS suffers from an intrinsic interference from the superficial tissues, which the near-infrared light must penetrate before reaching the deeper cerebral cortex. Therefore, the removal of signals captured by SS channels has been proposed to attenuate the systematic interference. This study aimed to investigate the task-related systemic artefacts, in a high-density montage covering the sensorimotor cortex. We compared the association between LS and SS channels over the contralateral motor cortex which was activated by a hand clenching task, with that over the ipsilateral cortex where no task-related activation was expected. Our findings provide important guidelines regarding how to removal SS signals in a high-density whole-head montage.


Assuntos
Córtex Motor , Espectroscopia de Luz Próxima ao Infravermelho , Artefatos , Imagem por Ressonância Magnética , Neuroimagem
4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1071-1074, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018171

RESUMO

While Deep Learning methods have been successfully applied to tackle a wide variety of prediction problems, their application has been mostly limited to data structured in a grid-like fashion. However, the study of the human brain "connectome" involves the representation of the brain as a graph with interacting nodes. In this paper, we extend the Graph Attention Network (GAT), a novel neural network (NN) architecture acting on the features of the nodes of a binary graph, to handle a set of graphs provided with node features and non-binary edge weights. We demonstrate the effectiveness of our architecture by training it multimodal data collected from a large homogeneous fMRI dataset (n=1003 individuals with multiple fMRI sessions per subject) made publicly available by the Human Connectome Project (HCP), demonstrating good performance and seamless integration of multimodal neuroimaging data. Our adaptation provides a powerful and flexible deep learning tool to integrate multimodal neuroimaging connectomics data in a predictive context.


Assuntos
Encéfalo , Conectoma , Atenção , Encéfalo/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética , Neuroimagem
5.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3727-3730, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018811

RESUMO

The coupling between neuronal activity and cerebral blood flow (CBF), known as neurovascular coupling, has been reported to be impaired after stroke. This study aims to investigate the neurovascular coupling impairment at the acute stage after ischemic stroke. Laser speckle contrast imaging (LSCI) was applied to measure the hemodynamic response to optogenetic excitation of sensorimotor neurons in healthy and ischemic brain. The results showed that the hemodynamic response to optogenetic stimulation decreased and the regional CBF response was correlated with the distance from the ischemic core at the acute stage, regardless of the change in resting CBF. Our results also demonstrated that excitatory neuronal stimulation of intact area could promote the recovery of neurovascular coupling, whereas peri-infarct neuronal excitation failed to restore neurovascular function 24 hrs after ischemia. These results suggested the intact periphery of penumbra as the target for excitatory stimulation in aspect of restoring the perfusion after ischemic stroke.


Assuntos
Isquemia Encefálica , Acoplamento Neurovascular , Acidente Vascular Cerebral , Encéfalo/diagnóstico por imagem , Isquemia Encefálica/diagnóstico por imagem , Humanos , Neuroimagem , Optogenética , Acidente Vascular Cerebral/diagnóstico por imagem
6.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1516-1519, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018279

RESUMO

Brain insults such as cerebral ischemia and intracranial hemorrhage are critical stroke conditions with high mortality rates. Currently, medical image analysis for critical stroke conditions is still largely done manually, which is time-consuming and labor-intensive. While deep learning algorithms are increasingly being applied in medical image analysis, the performance of these methods still needs substantial improvement before they can be widely used in the clinical setting. Among other challenges, the lack of sufficient labelled data is one of the key problems that has limited the progress of deep learning methods in this domain. To mitigate this bottleneck, we propose an integrated method that includes a data augmentation framework using a conditional Generative Adversarial Network (cGAN) which is followed by a supervised segmentation with a Convolutional Neural Network (CNN). The adopted cGAN generates meaningful brain images from specially altered lesion masks as a form of data augmentation to supplement the training dataset, while the CNN incorporates depth-wise-convolution based X-blocks as well as Feature Similarity Module (FSM) to ease and aid the training process, resulting in better lesion segmentation. We evaluate the proposed deep learning strategy on the Anatomical Tracings of Lesions After Stroke (ATLAS) dataset and show that this approach outperforms the current state-of-art methods in task of stroke lesion segmentation.


Assuntos
Aprendizado Profundo , Neuroimagem , Algoritmos , Encéfalo , Redes Neurais de Computação
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1568-1571, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018292

RESUMO

There is growing evidence that the use of stringent and dichotomic diagnostic categories in many medical disciplines (particularly 'brain sciences' as neurology and psychiatry) is an oversimplification. Although clear diagnostic boundaries remain useful for patients, families, and their access to dedicated NHS and health care services, the traditional dichotomic categories are not helpful to describe the complexity and large heterogeneity of symptoms across many and overlapping clinical phenotypes. With the advent of 'big' multimodal neuroimaging databases, data-driven stratification of the wide spectrum of healthy human physiology or disease based on neuroimages is theoretically become possible. However, this conceptual framework is hampered by severe computational constraints. In this paper we present a novel, deep learning based encode-decode architecture which leverages several parameter efficiency techniques generate latent deep embedding which compress the information contained in a full 3D neuroimaging volume by a factor 1000 while still retaining anatomical detail and hence rendering the subsequent stratification problem tractable. We train our architecture on 1003 brain scan derived from the human connectome project and demonstrate the faithfulness of the obtained reconstructions. Further, we employ a data driven clustering technique driven by a grid search in hyperparameter space to identify six different strata within the 1003 healthy community dwelling individuals which turn out to correspond to highly significant group differences in both physiological and cognitive data. Indicating that the well-known relationships between such variables and brain structure can be probed in an unsupervised manner through our novel architecture and pipeline. This opens the door to a variety of previously inaccessible applications in the realm of data driven stratification of large cohorts based on neuroimaging data.Clinical Relevance -With our approach, each person can be described and classified within a multi-dimensional space of data, where they are uniquely classified according to their individual anatomy, physiology and disease-related anatomical and physiological alterations.


Assuntos
Conectoma , Aprendizado Profundo , Neuroimagem , Encéfalo , Análise por Conglomerados , Bases de Dados Factuais , Humanos
8.
Curr Opin Ophthalmol ; 31(6): 455-461, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33009076

RESUMO

PURPOSE OF REVIEW: Optic nerve sheath meningiomas (ONSMs) are rare benign tumors of the anterior visual pathway which present with slowly progressive and painless vision loss and account for approximately 2% of all orbital tumors. This article provides an overview as well as an update on the ONSMs with regards to cause, epidemiology, clinical presentation, diagnosis, and management in adults and pediatric population. RECENT FINDINGS: The clinical presentation and prognosis of ONSMs can vary and largely depend on the location of tumor as well as the histologic type. Overall, the diagnosis is based on clinical presentation, examination, and neuroimaging findings. Nevertheless, delays in diagnosis or misdiagnosis are not uncommon and can result in higher morbidity rates. Recent advances in diagnostic as well as more effective and less-invasive treatment options are discussed in this review. SUMMARY: ONSMs are a rare cause of slowly progressive and inexorable visual loss. Although ONSM diagnosis depends on the characteristic clinical and radiologic findings, prompt diagnosis, and appropriate management is critical for favorable visual outcomes. Thus, current focus is optimizing diagnostic as well-treatment methods for patients with ONSMs.


Assuntos
Meningioma , Neoplasias do Nervo Óptico , Humanos , Meningioma/diagnóstico , Meningioma/terapia , Neuroimagem , Neoplasias do Nervo Óptico/diagnóstico , Neoplasias do Nervo Óptico/terapia , Prognóstico , Transtornos da Visão/etiologia
9.
AJNR Am J Neuroradiol ; 41(10): 1791-1796, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32912875

RESUMO

BACKGROUND AND PURPOSE: Coronavirus disease 2019 (COVID-19) is increasingly being recognized for its multiorgan involvement, including various neurological manifestations. We examined the frequency of acute intracranial abnormalities seen on CT and/or MR imaging in patients with COVID-19 and investigated possible associations between these findings and clinical parameters, including length of hospital stay, requirement for intubation, and development of acute kidney injury. MATERIALS AND METHODS: This was a retrospective study performed at a large academic hospital in the United States. A total of 641 patients presented to our institution between March 3, 2020, and May 6, 2020, for treatment of coronavirus disease 2019, of whom, 150 underwent CT and/or MR imaging of the brain. CT and/or MR imaging examinations were evaluated for the presence of hemorrhage, infarction, and leukoencephalopathy. The frequency of these findings was correlated with clinical variables, including body mass index, length of hospital stay, requirement for intubation, and development of acute kidney injury as documented in the electronic medical record. RESULTS: Of the 150 patients, 26 (17%) had abnormal CT and/or MR imaging findings, with hemorrhage in 11 of the patients (42%), infarction in 13 of the patients (50%), and leukoencephalopathy in 7 of the patients (27%). Significant associations were seen between abnormal CT/MR imaging findings and intensive care unit admission (P = .039), intubation (P = .004), and acute kidney injury (P = .030). CONCLUSIONS: A spectrum of acute neuroimaging abnormalities was seen in our cohort of patients with coronavirus disease 2019, including hemorrhage, infarction, and leukoencephalopathy. Significant associations between abnormal neuroimaging studies and markers of disease severity (intensive care unit admission, intubation, and acute kidney injury) suggest that patients with severe forms of coronavirus disease 2019 may have higher rates of neuroimaging abnormalities.


Assuntos
Betacoronavirus , Doenças do Sistema Nervoso Central/etiologia , Infecções por Coronavirus/complicações , Pneumonia Viral/complicações , Lesão Renal Aguda/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças do Sistema Nervoso Central/diagnóstico por imagem , Feminino , Humanos , Unidades de Terapia Intensiva , Tempo de Internação , Leucoencefalopatias , Masculino , Pessoa de Meia-Idade , Neuroimagem , Pandemias , Estudos Retrospectivos , Adulto Jovem
10.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(6): 822-827, 2020 Jun 30.
Artigo em Chinês | MEDLINE | ID: mdl-32895204

RESUMO

OBJECTIVE: To investigate the changes of functional connectivity (FC) in the suprachiasmatic nucleus (SCN) of patients with bipolar disorder and perform a cluster analysis of patients with bipolar disorder based on FC. METHODS: The study recruited 138 patients with bipolar disorder (BD) diagnosed according to the 4th edition of Diagnostic and Statistical Manual of Mental Disorders IV (DSM-IV) and 150 healthy control subjects. All the participants underwent resting-state functional magnetic resonance brain scans. DPARSF software was used to generate the FC diagram of the SCN. Based on the FC data, principal components analysis (PCA) and k-means in scikit-learn 0.20.1 were used for cluster analysis of the patients with bipolar disorder. RESULTS: Compared with the healthy controls, the patients showed enhanced functional connections between the SCN and the paraventricular nucleus and between the SCN and the dorsomedial hypothalamus nucleus. Based on these FC values, the optimal cluster of unsupervised k-means machine learning for bipolar disorder was 2, and the Silhouette coefficient was 0.49. CONCLUSIONS: Patients with bipolar disorder have changes in the FC of the SCN, and the FC of the rhythm pathway can divide bipolar disorder into two subtypes, suggesting that biological rhythm is one of the potential biomarkers of bipolar disorder.


Assuntos
Transtorno Bipolar , Encéfalo , Ritmo Circadiano , Humanos , Imagem por Ressonância Magnética , Neuroimagem
11.
PLoS One ; 15(8): e0236986, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32866198

RESUMO

White matter hyperintensities (WMHs) are among the most commonly observed marker of cerebrovascular disease. Age is a key risk factor for WMH development. Cardiorespiratory fitness (CRF) is associated with increased vessel compliance, but it remains unknown if high CRF affects WMH volume. This study explored the effects of CRF on WMH volume in community-dwelling older adults. We further tested the possibility of an interaction between CRF and age on WMH volume. Participants were 76 adults between the ages of 59 and 77 (mean age = 65.36 years, SD = 3.92) who underwent a maximal graded exercise test and structural brain imaging. Results indicated that age was a predictor of WMH volume (beta = .32, p = .015). However, an age-by-CRF interaction was observed such that higher CRF was associated with lower WMH volume in older participants (beta = -.25, p = .040). Our findings suggest that higher levels of aerobic fitness may protect cerebrovascular health in older adults.


Assuntos
Envelhecimento/patologia , Envelhecimento/fisiologia , Aptidão Cardiorrespiratória/fisiologia , Substância Branca/diagnóstico por imagem , Idoso , Circulação Cerebrovascular/fisiologia , Transtornos Cerebrovasculares/diagnóstico por imagem , Transtornos Cerebrovasculares/patologia , Transtornos Cerebrovasculares/fisiopatologia , Teste de Esforço , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroimagem , Fatores de Risco , Substância Branca/irrigação sanguínea , Substância Branca/patologia
12.
Nat Commun ; 11(1): 4518, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908146

RESUMO

The human brain is specialized for face processing, yet we sometimes perceive illusory faces in objects. It is unknown whether these natural errors of face detection originate from a rapid process based on visual features or from a slower, cognitive re-interpretation. Here we use a multifaceted approach to understand both the spatial distribution and temporal dynamics of illusory face representation in the brain by combining functional magnetic resonance imaging and magnetoencephalography neuroimaging data with model-based analysis. We find that the representation of illusory faces is confined to occipital-temporal face-selective visual cortex. The temporal dynamics reveal a striking evolution in how illusory faces are represented relative to human faces and matched objects. Illusory faces are initially represented more similarly to real faces than matched objects are, but within ~250 ms, the representation transforms, and they become equivalent to ordinary objects. This is consistent with the initial recruitment of a broadly-tuned face detection mechanism which privileges sensitivity over selectivity.


Assuntos
Reconhecimento Facial/fisiologia , Ilusões/fisiologia , Modelos Neurológicos , Lobo Temporal/fisiologia , Córtex Visual/fisiologia , Adolescente , Adulto , Mapeamento Encefálico , Simulação por Computador , Feminino , Humanos , Imagem por Ressonância Magnética , Magnetoencefalografia , Masculino , Neuroimagem , Estimulação Luminosa , Tempo de Reação , Lobo Temporal/diagnóstico por imagem , Córtex Visual/diagnóstico por imagem , Adulto Jovem
13.
J Neurol Sci ; 417: 117085, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32871412

RESUMO

INTRODUCTION: Coronavirus disease-19 (COVID-19) pandemic continues to grow all over the world. Several studies have been performed, focusing on understanding the acute respiratory syndrome and treatment strategies. However, there is growing evidence indicating neurological manifestations occur in patients with COVID-19. Similarly, the other coronaviruses (CoV) epidemics; severe acute respiratory syndrome (SARS-CoV-1) and Middle East respiratory syndrome (MERS-CoV) have been associated with neurological complications. METHODS: This systematic review serves to summarize available information regarding the potential effects of different types of CoV on the nervous system and describes the range of clinical neurological complications that have been reported thus far in COVID-19. RESULTS: Two hundred and twenty-five studies on CoV infections associated neurological manifestations in human were reviewed. Of those, 208 articles were pertinent to COVID-19. The most common neurological complaints in COVID-19 were anosmia, ageusia, and headache, but more serious complications, such as stroke, impairment of consciousness, seizures, and encephalopathy, have also been reported. CONCLUSION: There are several similarities between neurological complications after SARS-CoV-1, MERS-CoV and COVID-19, however, the scope of the epidemics and number of patients are very different. Reports on the neurological complications after and during COVID-19 are growing on a daily basis. Accordingly, comprehensive knowledge of these complications will help health care providers to be attentive to these complications and diagnose and treat them timely.


Assuntos
Betacoronavirus , Infecções por Coronavirus/complicações , Doenças do Sistema Nervoso/etiologia , Pandemias , Pneumonia Viral/complicações , Transtornos da Consciência/etiologia , Doenças dos Nervos Cranianos/etiologia , Encefalite Viral/etiologia , Humanos , Imagem por Ressonância Magnética , Doenças Musculares/etiologia , Neuroimagem , Doenças do Sistema Nervoso Periférico/etiologia , Convulsões/etiologia , Síndrome Respiratória Aguda Grave/complicações , Acidente Vascular Cerebral/etiologia
14.
Neuroradiol J ; 33(5): 353-367, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32894991

RESUMO

The ongoing COVID-19 pandemic has forced every radiology set-up to evolve and formulate guidelines for day-to-day functioning. The sub-speciality of neuroradiology, both diagnostic and neuro-intervention, forms a very important part of any radiology or 'neuro-care' set-up. The present document is a consensus statement of the Indian Society of Neuroradiology, prepared after reviewing the available data and working experience. It scientifically tries to answer many questions faced by neuroradiologists everyday in practice. It encompasses simple things such as which patients need to be imaged, what precautions are essential, the work-flows, cleaning of radiology equipment, how to carry out neuro-interventions in COVID-suspect patients, and what procedures/tests to avoid, or their alternatives, to minimise the spread of COVID infection both to the patients and health care personnel. As radiology set-ups can be large, every sub-speciality may have certain precautions which will not be covered in general guidelines, and this document tries to answer those for neuroradiologists. Carefully evolved Standards of Operating Procedure (SOPs) and guidelines are the need of the hour to guide in providing uninterrupted and adequate services to the needy without compromising the safety of the specialised work force and facilities involved.


Assuntos
Infecções por Coronavirus/prevenção & controle , Controle de Infecções/métodos , Neuroimagem/métodos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Radiologia Intervencionista/métodos , Pessoal Técnico de Saúde , Betacoronavirus , Desinfecção , Emergências , Fumigação , Humanos , Índia , Equipamento de Proteção Individual , Admissão e Escalonamento de Pessoal , Radiologia/métodos , Sociedades Médicas , Ventilação
15.
J Oral Facial Pain Headache ; 34(3): 222-235, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32870951

RESUMO

AIMS: To evaluate the available literature on structural and functional brain abnormalities in trigeminal neuralgia (TN) using several brain magnetic resonance imaging (MRI) techniques to further understand the central mechanisms of TN. METHODS: PubMed and Web of Science databases and the reference lists of identified studies were searched to identify potentially eligible studies through January 2019. Eligible articles were assessed for risk of bias and reviewed by two independent researchers. RESULTS: A total of 17 articles meeting the inclusion criteria were included in this study. The methodologic quality of the included studies was moderate. A total of 10 studies evaluated structural gray matter (GM) changes, and there was reasonable evidence that the GM of some specific brain regions changed in TN patients. In addition, there was a significant change in the root entry zone of the trigeminal nerve and in several regions of white matter. Functional changes in resting state were assessed in 9 studies. TN patients showed increased activation of resting state, and this activation was reduced in specific brain regions. There were several studies that focused on the correlation between functional parameters or strength of functional connectivity and clinical features (eg, visual analog score and pain duration), but each study focused on different brain areas or different functional connectivities within the brain. CONCLUSION: There is moderate evidence that TN patients show structural brain differences in specific cortical and subcortical regions. In addition, TN patients show changes in pain-related functional connections in the resting state. Future research should focus on longitudinal designs and integration of different brain-imaging techniques.


Assuntos
Neuralgia do Trigêmeo , Encéfalo , Substância Cinzenta , Humanos , Imagem por Ressonância Magnética , Neuroimagem
17.
AJNR Am J Neuroradiol ; 41(10): 1760-1767, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32819907

RESUMO

When preparing for the coronavirus disease 2019 pandemic and its effects on the CNS, radiologists should be familiar with neuroimaging appearances in past zoonotic infectious disease outbreaks. Organisms that have crossed the species barrier from animals to humans include viruses such as Hendra, Nipah, Severe Acute Respiratory Syndrome, and influenza, as well as bacteria and others. Brain CT and MR imaging findings have included cortical abnormalities, microinfarction in the white matter, large-vessel occlusion, and features of meningitis. In particular, the high sensitivity of diffusion-weighted MR imaging in detecting intracranial abnormalities has been helpful in outbreaks. Although the coronaviruses causing the previous Severe Acute Respiratory Syndrome outbreak and the current coronavirus disease 19 pandemic are related, it is important to be aware of their similarities as well as potential differences. This review describes the neuroimaging appearances of selected zoonotic outbreaks so that neuroradiologists can better understand the current pandemic and potential future outbreaks.


Assuntos
Betacoronavirus , Doenças do Sistema Nervoso Central/diagnóstico por imagem , Infecções por Coronavirus , Pandemias , Pneumonia Viral , Animais , Infecções por Coronavirus/etiologia , Surtos de Doenças , Humanos , Sistema Nervoso , Neuroimagem , Pneumonia Viral/etiologia
18.
PLoS Biol ; 18(8): e3000840, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32845876

RESUMO

Humans' propensity to acquire literacy relates to several factors, including the ability to understand speech in noise (SiN). Still, the nature of the relation between reading and SiN perception abilities remains poorly understood. Here, we dissect the interplay between (1) reading abilities, (2) classical behavioral predictors of reading (phonological awareness, phonological memory, and rapid automatized naming), and (3) electrophysiological markers of SiN perception in 99 elementary school children (26 with dyslexia). We demonstrate that, in typical readers, cortical representation of the phrasal content of SiN relates to the degree of development of the lexical (but not sublexical) reading strategy. In contrast, classical behavioral predictors of reading abilities and the ability to benefit from visual speech to represent the syllabic content of SiN account for global reading performance (i.e., speed and accuracy of lexical and sublexical reading). In individuals with dyslexia, we found preserved integration of visual speech information to optimize processing of syntactic information but not to sustain acoustic/phonemic processing. Finally, within children with dyslexia, measures of cortical representation of the phrasal content of SiN were negatively related to reading speed and positively related to the compromise between reading precision and reading speed, potentially owing to compensatory attentional mechanisms. These results clarify the nature of the relation between SiN perception and reading abilities in typical child readers and children with dyslexia and identify novel electrophysiological markers of emergent literacy.


Assuntos
Córtex Cerebral/fisiologia , Ruído , Leitura , Fala/fisiologia , Comportamento , Criança , Dislexia/fisiopatologia , Humanos , Modelos Lineares , Neuroimagem , Fonética
19.
J Neurol Sci ; 417: 117087, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32798855

RESUMO

INTRODUCTION: The coronavirus disease 2019 (Covid-19) pandemic has led to challenges in provision of care, clinical assessment and communication with families. The unique considerations associated with evaluation of catastrophic brain injury and death by neurologic criteria in patients with Covid-19 infection have not been examined. METHODS: We describe the evaluation of six patients hospitalized at a health network in New York City in April 2020 who had Covid-19, were comatose and had absent brainstem reflexes. RESULTS: Four males and two females with a median age of 58.5 (IQR 47-68) were evaluated for catastrophic brain injury due to stroke and/or global anoxic injury at a median of 14 days (IQR 13-18) after admission for acute respiratory failure due to Covid-19. All patients had hypotension requiring vasopressors and had been treated with sedative/narcotic drips for ventilator dyssynchrony. Among these patients, 5 had received paralytics. Apnea testing was performed for 1 patient due to the decision to withdraw treatment (n = 2), concern for inability to tolerate testing (n = 2) and observation of spontaneous respirations (n = 1). The apnea test was aborted due to hypoxia and hypotension. After ancillary testing, death was declared in three patients based on neurologic criteria and in three patients based on cardiopulmonary criteria (after withdrawal of support (n = 2) or cardiopulmonary arrest (n = 1)). A family member was able to visit 5/6 patients prior to cardiopulmonary arrest/discontinuation of organ support. CONCLUSION: It is feasible to evaluate patients with catastrophic brain injury and declare brain death despite the Covid-19 pandemic, but this requires unique considerations.


Assuntos
Betacoronavirus , Morte Encefálica/diagnóstico , Lesões Encefálicas/etiologia , Infecções por Coronavirus/complicações , Pandemias , Pneumonia Viral/complicações , Idoso , Apneia/etiologia , Hemorragia Cerebral/etiologia , Contraindicações de Procedimentos , Eletroencefalografia , Feminino , Parada Cardíaca/etiologia , Humanos , Hipóxia Encefálica/etiologia , Masculino , Pessoa de Meia-Idade , Neuroimagem , Exame Neurológico , Relações Profissional-Família , Obtenção de Tecidos e Órgãos , Revelação da Verdade
20.
Ideggyogy Sz ; 73(7-08): 286-288, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32750246

RESUMO

Intracranial localization of Ewing's sarcoma is considerably very rare. Herein, we present clinical and neuroimaging findings regarding a 4-year-old boy with intracranial Ewing's sarcoma. He was born prematurely, suffered intraventricular haemorrhage, posthaemorrhagic hydrocephalus developed, and a ventriculoperitoneal shunt was inserted in the newborn period. The patient endured re-gular follow ups, no signs of shunt malfunction nor increased intracranial pressure were observed. The last neuroima-ging examination was performed at 8 months of age. Upon reaching the age of 4 years, repeated vomiting and focal seizures began, and symptoms of increased intracranial pressure were detected. A brain MRI depicted a left frontoparietal space-occupying lesion infiltrating the superior sagittal sinus. The patient underwent a craniotomy resulting in the total excision of the tumour. The histological examination of the tissue revealed a small round blue cell tumour. The diagnosis was confirmed by the detection of EWSR1 gene translocation with FISH (fluorescent in situ hybridization). No additional metastases were detected during the staging examinations. The patient was treated in accordance to the EuroEwing 99 protocol. Today, ten years onward, the patient is tumour and seizure free and has a reasonably high quality of life.


Assuntos
Encéfalo/diagnóstico por imagem , Sarcoma de Ewing/diagnóstico , Convulsões/etiologia , Vômito/etiologia , Neoplasias Ósseas/genética , Pré-Escolar , Craniotomia , Humanos , Hibridização in Situ Fluorescente , Pressão Intracraniana , Imagem por Ressonância Magnética , Masculino , Neuroimagem , Qualidade de Vida , Proteína EWS de Ligação a RNA , Sarcoma de Ewing/complicações , Sarcoma de Ewing/genética , Sarcoma de Ewing/cirurgia , Translocação Genética , Resultado do Tratamento
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