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1.
Int J Mol Sci ; 22(6)2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33799851

RESUMO

Multiple lines of evidence suggest that dysfunction of the metabotropic glutamate receptor subtype 5 (mGluR5) plays a role in the pathogenesis of autism spectrum disorder (ASD). Yet animal and human investigations of mGluR5 expression provide conflicting findings about the nature of dysregulation of cerebral mGluR5 pathways in subtypes of ASD. The demonstration of reduced mGluR5 expression throughout the living brains of men with fragile X syndrome (FXS), the most common known single-gene cause of ASD, provides a clue to examine mGluR5 expression in ASD. We aimed to (A) compare and contrast mGluR5 expression in idiopathic autism spectrum disorder (IASD), FXS, and typical development (TD) and (B) show the value of positron emission tomography (PET) for the application of precision medicine for the diagnosis and treatment of individuals with IASD, FXS, and related conditions. Two teams of investigators independently administered 3-[18F]fluoro-5-(2-pyridinylethynyl)benzonitrile ([18F]FPEB), a novel, specific mGluR5 PET ligand to quantitatively measure the density and the distribution of mGluR5s in the brain regions, to participants of both sexes with IASD and TD and men with FXS. In contrast to participants with TD, mGluR5 expression was significantly increased in the cortical regions of participants with IASD and significantly reduced in all regions of men with FXS. These results suggest the feasibility of this protocol as a valuable tool to measure mGluR5 expression in clinical trials of individuals with IASD and FXS and related conditions.


Assuntos
Transtorno do Espectro Autista/metabolismo , Córtex Cerebral/metabolismo , Síndrome do Cromossomo X Frágil/metabolismo , Receptor de Glutamato Metabotrópico 5/metabolismo , Adolescente , Adulto , Animais , Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/genética , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Córtex Cerebral/diagnóstico por imagem , Feminino , Síndrome do Cromossomo X Frágil/diagnóstico por imagem , Síndrome do Cromossomo X Frágil/genética , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Tomografia por Emissão de Pósitrons/métodos , Receptor de Glutamato Metabotrópico 5/genética , Adulto Jovem
2.
Neuroscience ; 465: 60-70, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33887385

RESUMO

Twins provide a valuable perspective for exploring the pathological mechanism of autism spectrum disorder (ASD). We aim to analyze differences in the topological properties of the white matter (WM) network between monozygotic twins with ASD (MZCo-ASD) and children with typical development (TD). We enrolled 67 subjects aged 2-9 years. Twenty-three pairs of MZCo-ASD and 21 singleton children with TD completed clinical assessments and diffusion tensor imaging (DTI). Graph theory was used to compare the topological properties of the WM network between the two groups, and analyzed their correlations with the severity of clinical symptoms. We found that the global efficiency (Eg) of MZCo-ASD is weaker than that of TD children, while the shortest path length (Lp) of MZCo-ASD is longer than that of TD children, and MZCo-ASD have three unique hubs (the bilateral dorsolateral superior frontal gyrus and right insula). Eg and Lp were both correlated with the repetitive behavior scores of the Autism Diagnostic Interview-Revised (ADI-R) in the MZCo-ASD group, and the nodal efficiency of the dorsal superior frontal gyrus (SFGdor) was correlated with the ADI-R scores of repetitive behaviors. Left SFGdor nodal efficiency was correlated with Repetitive Behavior and Communication, two core symptoms of autism. The results implicated that MZCo-ASD had atypical brain structural network attributes and node distributions. Using MZCo-ASD, we found that the WM topological properties that correlate with the severity of ASD core symptoms were Eg, Lp, and the nodal efficiency of the SFGdor.


Assuntos
Transtorno do Espectro Autista , Substância Branca , Transtorno do Espectro Autista/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Criança , Imagem de Tensor de Difusão , Humanos , Gêmeos Monozigóticos , Substância Branca/diagnóstico por imagem
3.
Brain Topogr ; 34(3): 306-322, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33905003

RESUMO

Autism spectrum disorder (ASD) is a developmental disorder characterized by defects in social interaction. The past functional connectivity studies using resting-state fMRI have found both patterns of hypo-connectivity and hyper-connectivity in ASD and proposed the age as an important factor on functional connectivity disorders. However, this influence is not clearly characterized yet. Previous studies have often examined the functional connectivity disorders in particular brain regions in an age group or a mixture of age groups. The present study compares whole-brain within-connectivity and between-connectivity between ASD individuals and typically developing (TD) controls in three age groups including children (< 11 years), adolescents (11-18 years), and adults (> 18 years), each comprising 21 ASD individuals and 21 TD controls. The age groups were matched for age, Full IQ, and gender. Independent component analysis and dual regression were used to investigate within-connectivity. The full and partial correlations between ICs were used to investigate between-connectivity. Examination of the within-connectivity showed hyper-connectivity, especially in cerebellum and brainstem in ASD children but both hyper/hypo connectivity in adolescents and ASD adults. In ASD children, difference in the between-connectivity among default mode network (DMN), salience-executive network and fronto-parietal network were observed. There was also a negative correlation between DMN and temporal network. Full correlation comparison between ASD adolescents and TD individuals showed significant differences between cerebellum and DMN. Our results supported just the hyper-connectivity in childhood, but both hypo and hyper-connectivity after childhood and hypothesized that abnormal resting connections in ASD exist in the regions of the brain known to be involved in social cognition.


Assuntos
Transtorno do Espectro Autista , Adolescente , Adulto , Transtorno do Espectro Autista/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Criança , Humanos , Imageamento por Ressonância Magnética , Vias Neurais/diagnóstico por imagem
4.
Clin EEG Neurosci ; 52(2): 126-135, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33370176

RESUMO

This brief article is an overview of my personal experience over the past almost 10 years of the clinical use of EEG and quantitative EEG (qEEG) functional neuroimaging in a busy pediatric neurology practice. The concomitant use of surface EEG and functional electromagnetic EEG neuroimaging/qEEG in clinical practice provides significant additional clinical and neurophysiologic information. The qEEG is a noninvasive, inexpensive, portable technique with high temporal resolution (milliseconds) and improving spatial resolution (down to 3 mm3) and is an appropriate and validated tool for investigation of abnormal brain dynamics and connectivity of neuronal networks in clinical disorders of the brain. This article describes the daily applicability and utility of this modality in assisting diagnosis and clinical management of patients with a wide variety of presenting symptoms, including headaches, tics, autism spectrum disorder, inattention, sleep dysregulation, anxiety, and depression. The ease of data acquisition and analysis in clinical practices, coupled with skilled interpretation and clinical application, makes this tool one of the most valuable clinical tools to complement a thorough history and examination process.


Assuntos
Transtorno do Espectro Autista , Transtorno do Espectro Autista/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Criança , Eletroencefalografia , Neuroimagem Funcional , Humanos
5.
Med Phys ; 48(5): 2315-2326, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33378589

RESUMO

PURPOSE: Task-based fMRI (TfMRI) is a diagnostic imaging modality for observing the effects of a disease or other condition on the functional activity of the brain. Autism spectrum disorder (ASD) is a pervasive developmental disorder associated with impairments in social and linguistic abilities. Machine learning algorithms have been widely utilized for brain imaging aiming for objective ASD diagnostics. Recently, deep learning methods have been gaining more attention for fMRI classification. The goal of this paper is to develop a convolutional neural network (CNN)-based framework to help in global diagnosis of ASD using TfMRI data that are collected from a response to speech experiment. METHODS: To achieve this goal, the proposed framework adopts a novel imaging marker integrating both spatial and temporal information that are related to the functional activity of the brain. The developed pipeline consists of three main components. In the first step, the collected TfMRI data are preprocessed and parcellated using the Harvard-Oxford probabilistic atlas included with the fMRIB Software Library (FSL). Second, a group analysis using FSL is performed between ASD and typically developing (TD) children to identify significantly activated brain areas in response to the speech task. In order to reduce brain spatial dimensionality, a K-means clustering technique is performed on such significant brain areas. Informative blood oxygen level-dependent (BOLD) signals are extracted from each cluster. A compression step for each extracted BOLD signal using discrete wavelet transform (DWT) has been proposed. The adopted wavelets are similar to the expected hemodynamic response which enables DWT to compress the BOLD signal while highlighting its activation information. Finally, a deep learning 2D CNN network is used to classify the patients as ASD or TD based on extracted features from the previous step. RESULTS: Preliminary results on 100 TfMRI dataset (50 ASD, 50 TD) obtain 80% correct global classification using tenfold cross validation (with sensitivity = 84%, specificity = 76%). CONCLUSION: The experimental results show the high accuracy of the proposed framework and hold promise for the presented framework as a helpful adjunct to currently used ASD diagnostic tools.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno Autístico/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Criança , Diagnóstico Precoce , Humanos , Imageamento por Ressonância Magnética , Redes Neurais de Computação , Análise de Ondaletas
6.
Sci Rep ; 10(1): 22417, 2020 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-33376247

RESUMO

While previous research has investigated neuroradiological findings in autism spectrum disorder (ASD) and attention-deficit hyperactivity disorder (ADHD), the entire range of neurodevelopmental disorders (NDDs) has not yet been well-studied using magnetic resonance imaging (MRI). Considering the overlap among NDDs and simultaneous development of the brain and face, guided by molecular signaling, we examined the relationship of actionable and incidental (non-actionable) MRI findings and NDD diagnoses together with facial morphological variants and genetic copy number variants (CNVs). A cross-sectional study was conducted with a twin cohort 8-36 years of age (57% monozygotic, 40% dizygotic), including 372 subjects (46% with NDDs; 47% female) imaged by MRI, 280 with data for facial morphological variants, and 183 for CNVs. Fifty-one percent of participants had MRI findings. Males had a statistically significantly higher percentage of MRI findings (57.7%) compared with females (43.8%, p = 0.03). Twin zygosity was not statistically significantly correlated with incidence or severity of specific MRI findings. No statistically significant association was found between MRI findings and any NDD diagnosis or facial morphological variants; however, MRI findings were statistically significantly associated with the number of CNVs (OR 1.20, 95% CI 1.00-1.44, p = 0.05, adjusted OR for sex 1.24, 95% CI 1.03-1.50, p = 0.02). When combining the presence of MRI findings, facial morphological variants, and CNVs, statistically significant relationships were found with ASD and ADHD diagnoses (p = 0.0006 and p = 0.002, respectively). The results of this study demonstrate that the ability to identify NDDs from combined radiology, morphology, and CNV assessments may be possible. Additionally, twins do not appear to be at increased risk for neuroradiological variants.


Assuntos
Transtornos de Deficit da Atenção e do Comportamento Disruptivo , Transtorno do Espectro Autista , Dosagem de Genes , Imageamento por Ressonância Magnética , Polimorfismo Genético , Caracteres Sexuais , Gêmeos Dizigóticos , Gêmeos Monozigóticos , Adolescente , Adulto , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/diagnóstico por imagem , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/epidemiologia , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/genética , Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/epidemiologia , Transtorno do Espectro Autista/genética , Criança , Feminino , Humanos , Incidência , Masculino , Índice de Gravidade de Doença
7.
Nat Commun ; 11(1): 5272, 2020 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-33077750

RESUMO

16p11.2 and 22q11.2 Copy Number Variants (CNVs) confer high risk for Autism Spectrum Disorder (ASD), schizophrenia (SZ), and Attention-Deficit-Hyperactivity-Disorder (ADHD), but their impact on functional connectivity (FC) remains unclear. Here we report an analysis of resting-state FC using magnetic resonance imaging data from 101 CNV carriers, 755 individuals with idiopathic ASD, SZ, or ADHD and 1,072 controls. We characterize CNV FC-signatures and use them to identify dimensions contributing to complex idiopathic conditions. CNVs have large mirror effects on FC at the global and regional level. Thalamus, somatomotor, and posterior insula regions play a critical role in dysconnectivity shared across deletions, duplications, idiopathic ASD, SZ but not ADHD. Individuals with higher similarity to deletion FC-signatures exhibit worse cognitive and behavioral symptoms. Deletion similarities identified at the connectivity level could be related to the redundant associations observed genome-wide between gene expression spatial patterns and FC-signatures. Results may explain why many CNVs affect a similar range of neuropsychiatric symptoms.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/genética , Transtorno do Espectro Autista/genética , Encéfalo/fisiopatologia , Esquizofrenia/genética , Adolescente , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico por imagem , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/fisiopatologia , Transtorno do Espectro Autista/psicologia , Encéfalo/diagnóstico por imagem , Criança , Pré-Escolar , Cognição , Estudos de Coortes , Variações do Número de Cópias de DNA , Feminino , Deleção de Genes , Duplicação Gênica , Humanos , Imageamento por Ressonância Magnética , Masculino , Mutação , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/fisiopatologia , Adulto Jovem
8.
PLoS One ; 15(7): e0236415, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32702017

RESUMO

There is a significant delay between seeking help and a confirmed diagnosis of Autism Spectrum Disorder (ASD). This delay can lead to poor outcomes for both the families and individuals. Telehealth potentially offers a way of improving the diagnostic pathway for ASD. We conducted a scoping review examining which telehealth approaches are used in the diagnosis and assessment of ASD in children and adults, whether they are feasible and acceptable, and how they compare with face-to-face diagnosis and assessment methods. A search for all peer-reviewed articles, combining the terms of autism and telehealth was conducted from 2000 to 2019. A total of 10 studies were identified for inclusion in the review. This review of the literature found there to be two methods of using telehealth: (a) Real-Time method e.g. video conferencing that enables teams in different areas to consult with the families and to assess the child/adult in real time and (b) A Store-and-Forward method as Naturalistic Observation Diagnostic Assessment (NODA) system to upload videos of child's behaviors to a webportal that enables the clinicians to make an assessment remotely. The findings were positive, finding there to be high agreement in terms of the diagnosis between remote methods and face to face methods and with high levels of satisfaction among the families and clinicians. This field is in the very early stages and so only studies with small sample size using surveys and interviews were identified but the findings suggest that there is potential for telehealth methods to improve access to assessment and diagnosis of ASD used in conjunction with existing methods, especially for those with clear autism traits and adults with ASD. Larger randomised controlled trials of this technology are warranted.


Assuntos
Transtorno do Espectro Autista/diagnóstico , Comportamento Infantil , Telemedicina/tendências , Comunicação por Videoconferência/tendências , Adulto , Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/patologia , Criança , Feminino , Humanos , Masculino , Inquéritos e Questionários
9.
Am J Psychiatry ; 177(6): 518-525, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32375538

RESUMO

OBJECTIVE: Sleep patterns in children with autism spectrum disorder (ASD) appear to diverge from typical development in the second or third year of life. Little is known, however, about the occurrence of sleep problems in infants who later develop ASD and possible effects on early brain development. In a longitudinal neuroimaging study of infants at familial high or low risk for ASD, parent-reported sleep onset problems were examined in relation to subcortical brain volumes in the first 2 years of life. METHODS: A total of 432 infants were included across three study groups: infants at high risk who developed ASD (N=71), infants at high risk who did not develop ASD (N=234), and infants at low risk (N=127). Sleep onset problem scores (derived from an infant temperament measure) were evaluated in relation to longitudinal high-resolution T1 and T2 structural imaging data acquired at 6, 12, and 24 months of age. RESULTS: Sleep onset problems were more common at 6-12 months among infants who later developed ASD. Infant sleep onset problems were related to hippocampal volume trajectories from 6 to 24 months only for infants at high risk who developed ASD. Brain-sleep relationships were specific to the hippocampus; no significant relationships were found with volume trajectories of other subcortical structures examined (the amygdala, caudate, globus pallidus, putamen, and thalamus). CONCLUSIONS: These findings provide initial evidence that sleep onset problems in the first year of life precede ASD diagnosis and are associated with altered neurodevelopmental trajectories in infants at high familial risk who go on to develop ASD. If replicated, these findings could provide new insights into a potential role of sleep difficulties in the development of ASD.


Assuntos
Transtorno do Espectro Autista/epidemiologia , Hipotálamo/diagnóstico por imagem , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/patologia , Transtorno do Espectro Autista/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Núcleo Caudado/diagnóstico por imagem , Núcleo Caudado/patologia , Pré-Escolar , Feminino , Globo Pálido/diagnóstico por imagem , Globo Pálido/patologia , Humanos , Hipotálamo/patologia , Lactente , Imageamento por Ressonância Magnética , Masculino , Tamanho do Órgão , Putamen/diagnóstico por imagem , Putamen/patologia , Distúrbios do Início e da Manutenção do Sono/diagnóstico por imagem , Distúrbios do Início e da Manutenção do Sono/fisiopatologia , Latência do Sono , Tálamo/diagnóstico por imagem , Tálamo/patologia
10.
Psychiatry Res Neuroimaging ; 298: 111063, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32179248

RESUMO

The social brain hypothesis is regarded as a powerful theory to understand social cognition. Individuals with autism spectrum disorder (ASD) have specific deficits in social and communicative behavior, but the exact relationship between these deficits and abnormalities in the social brain remains unclear. The high heritability of this disorder makes it important to focus on the first-degree relatives of those affected. Research focusing on genetically at-risk (yet healthy) relatives of patients with ASD is critical to the study of neuroimaging endophenotypes. We conducted a voxel-wise activation likelihood estimation (ALE) meta-analysis of 9 functional neuroimaging studies published during the period from 2006 to 2018. These studies included 200 individuals with ASD, 216 unaffected family members (UF), and 235 typical development controls (TD). The voxel-wise significance threshold was p < 0.01 (uncorrected p = 0.001).The ALE meta-analyses showed hyperactivation in the inferior frontal gyrus (IFG) and superior temporal gyrus (STG) among individuals with ASD and UF, compared with TD individuals. Group comparisons showed greater likelihood of hyperactivation in the amygdala for ASD, compared with UF and TD.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Encéfalo/fisiopatologia , Endofenótipos , Família , Neuroimagem Funcional , Comportamento Social , Percepção Social , Transtorno do Espectro Autista/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Humanos
11.
Brain Dev ; 42(4): 315-321, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32088024

RESUMO

INTRODUCTION: Arterial spin labeling (ASL) is a non-invasive magnetic resonance imaging (MRI) technique that can measure regional cerebral blood flow (rCBF) without radiation exposure. This study aimed to evaluate rCBF in individuals with autism and their age-matched controls, globally and regionally. METHODS: We performed ASL MRI (3 T, pulsed-continuous ASL, 3 delayed ASL imaging sequences) for 33 patients with autism spectrum disorder (ASD) (average age: 7.3 years, range: 2-14 years). Nineteen children (average age: 8.6 years, range: 3-15 years) without ASD and intellectual delay were included as controls. Patients with morphological abnormalities detected on MRI were excluded. Objective analysis was performed with automatic region of interest analysis of the ASL results. The Mann-Whitney U test was used to compare the rCBF results between the groups. RESULTS: Compared to the controls, patients with ASD showed a statistically significant decrease in rCBF, respectively, in the insula [left, rCBF 51.8 ±â€¯9.5 mL/100 g/min (mean ±â€¯SD) versus 59.9 ±â€¯9.8, p = 0.0017; right, 51.2 ±â€¯10.1 versus 57.8 ±â€¯8.8, p = 0.0354], superior parietal lobule (left, 44.6 ±â€¯8.4 versus 52.0 ±â€¯7.8, p = 0.003), superior temporal gyrus (left, 50.0 ±â€¯8.6 versus 56.9 ±â€¯8.6, p = 0.007; right, 49.5 ±â€¯8.4 versus 56.4 ±â€¯7.7, p = 0.0058), and inferior frontal gyrus (left, 53.0 ±â€¯9.8 versus 59.3 ±â€¯9.9, p = 0.0279), which are associated with the mirror neuron system. CONCLUSIONS: We concluded that patients with ASD showed a statistically significant decline in CBF in regions associated with the mirror neuron system. The advantages of ASL MRI include low invasiveness (no radiation exposure) and short imaging time (approximately 5 min). Studies with larger sample sizes are required to establish the diagnostic value of ASL MRI for ASD.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Encéfalo/irrigação sanguínea , Encéfalo/fisiopatologia , Imageamento por Ressonância Magnética , Fluxo Sanguíneo Regional , Adolescente , Transtorno do Espectro Autista/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Criança , Pré-Escolar , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Marcadores de Spin
12.
Clin Imaging ; 60(2): 180-185, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31927175

RESUMO

The phosphatase and tensin homolog (PTEN) located at 10q23.31 is a tumor suppressor gene expressed ubiquitously, and loss of function mutations lead to aberrant growth, angiogenesis, and an increased risk for a variety of tumors. PTEN mutations have been associated with multiple abnormalities in the central nervous system, and a number of clinical phenotypes are now attributed to germline PTEN mutations, collectively referred to as PTEN hamartoma tumor syndrome (PHTS). Most notably, these include Cowden syndrome (CS), Bannayan-Riley-Ruvalcaba syndrome (BRRS), and autism spectrum disorders with macrocephaly. It is important to recognize the neuroimaging features associated with PTEN mutations to not only avoid misdiagnosis in cases of known PHTS but also to guide genetic testing in patients who do not yet have an established diagnosis. In this review, the central nervous system imaging features of PTEN-related disorders are discussed.


Assuntos
Sistema Nervoso Central/patologia , Mutação em Linhagem Germinativa , Síndrome do Hamartoma Múltiplo/patologia , PTEN Fosfo-Hidrolase/genética , Anormalidades Múltiplas , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/patologia , Sistema Nervoso Central/diagnóstico por imagem , Feminino , Síndrome do Hamartoma Múltiplo/diagnóstico , Síndrome do Hamartoma Múltiplo/diagnóstico por imagem , Humanos , Masculino , Megalencefalia , Mutação , Fenótipo
13.
J Am Acad Child Adolesc Psychiatry ; 59(3): 348-349, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31926223

RESUMO

Unraveling the altered brain-behavior relationships in autism spectrum disorder (ASD) has been challenging because of the limitations of sample size and methodologies that are still evolving. Recently, pediatric neuroimaging has undergone considerable advancement by harnessing resting-state functional magnetic resonance imaging (rfMRI),1 in which methodologies can be applied to quantify functional connectivity (FC) from spontaneous fluctuations of brain activity. Benefiting from relatively easy data collection from clinical samples and the ability to harmonize these samples, rfMRI has supported the emergence of open pediatric neuroimaging science (OPENS) through the pooling and sharing of large-scale neuroimaging data by and for the research community (eg, the Autism Brain Imaging Data Exchange [ABIDE]2,3). Big data OPENS ASD studies have revealed functional impairments in both sensory and cognitive brain networks. However, whether these impairments reflect a miswired connectome of network interplay in ASD remains to be elucidated.


Assuntos
Transtorno do Espectro Autista , Conectoma , Transtorno do Espectro Autista/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Criança , Cognição , Humanos , Imageamento por Ressonância Magnética , Vias Neurais/diagnóstico por imagem , Integração de Sistemas
14.
Autism Res ; 13(1): 32-44, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31657138

RESUMO

The aim was to go beyond functional connectivity, by measuring in the first large-scale study differences in effective, that is directed, connectivity between brain areas in autism compared to controls. Resting-state functional magnetic resonance imaging was analyzed from the Autism Brain Imaging Data Exchange (ABIDE) data set in 394 people with autism spectrum disorder and 473 controls, and effective connectivity (EC) was measured between 94 brain areas. First, in autism, the middle temporal gyrus and other temporal areas had lower effective connectivities to the precuneus and cuneus, and these were correlated with the Autism Diagnostic Observational Schedule total, communication, and social scores. This lower EC from areas implicated in face expression analysis and theory of mind to the precuneus and cuneus implicated in the sense of self may relate to the poor understanding of the implications of face expression inputs for oneself in autism, and to the reduced theory of mind. Second, the hippocampus and amygdala had higher EC to the middle temporal gyrus in autism, and these are thought to be back projections based on anatomical evidence and are weaker than in the other direction. This may be related to increased retrieval of recent and emotional memories in autism. Third, some prefrontal cortex areas had higher EC with each other and with the precuneus and cuneus. Fourth, there was decreased EC from the temporal pole to the ventromedial prefrontal cortex, and there was evidence for lower activity in the ventromedial prefrontal cortex, a brain area implicated in emotion-related decision-making. Autism Res 2020, 13: 32-44. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: To understand autism spectrum disorders better, it may be helpful to understand whether brain systems cause effects on each other differently in people with autism. In this first large-scale neuroimaging investigation of effective connectivity in people with autism, it is shown that parts of the temporal lobe involved in facial expression identification and theory of mind have weaker effects on the precuneus and cuneus implicated in the sense of self. This may relate to the poor understanding of the implications of face expression inputs for oneself in autism, and to the reduced theory of mind.


Assuntos
Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/fisiopatologia , Mapeamento Encefálico/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Feminino , Humanos , Masculino
15.
Autism ; 24(2): 364-373, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31339349

RESUMO

Continued human and animal research has strengthened evidence for aberrant excitatory-inhibitory neural processes underlying autism and schizophrenia spectrum disorder psychopathology, particularly psychosocial functioning, in clinical and nonclinical populations. We investigated the extent to which autistic traits and schizotypal dimensions were modulated by the interactive relationship between excitatory glutamate and inhibitory GABA neurotransmitter concentrations in the social processing area of the superior temporal cortex using proton magnetic resonance spectroscopy. In total, 38 non-clinical participants (20 females; age range = 18-35 years, mean (standard deviation) = 23.22 (5.52)) completed the autism spectrum quotient and schizotypal personality questionnaire, and underwent proton magnetic resonance spectroscopy to quantify glutamate and GABA concentrations in the right and left superior temporal cortex. Regression analyses revealed that glutamate and GABA interactively modulated autistic social skills and schizotypal interpersonal features (pcorr < 0.05), such that those with high right superior temporal cortex glutamate but low GABA concentrations exhibited poorer social and interpersonal skills. These findings evidence an excitation-inhibition imbalance that is specific to psychosocial features across the autism and schizophrenia spectra.


Assuntos
Transtorno do Espectro Autista/diagnóstico por imagem , Cognição/fisiologia , Ácido Glutâmico/metabolismo , Transtorno da Personalidade Esquizotípica/diagnóstico por imagem , Habilidades Sociais , Transmissão Sináptica , Lobo Temporal/diagnóstico por imagem , Ácido gama-Aminobutírico/metabolismo , Adolescente , Adulto , Atenção , Transtorno do Espectro Autista/metabolismo , Transtorno do Espectro Autista/fisiopatologia , Feminino , Voluntários Saudáveis , Humanos , Relações Interpessoais , Masculino , Espectroscopia de Prótons por Ressonância Magnética , Transtorno da Personalidade Esquizotípica/metabolismo , Transtorno da Personalidade Esquizotípica/fisiopatologia , Lobo Temporal/metabolismo , Adulto Jovem
16.
Brain Connect ; 10(1): 18-28, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31884804

RESUMO

Autism spectrum disorders (ASDs) have been linked to atypical communication among distributed brain networks. However, despite decades of research, the exact nature of these differences between typically developing (TD) individuals and those with ASDs remains unclear. ASDs have been widely studied using resting-state neuroimaging methods, including both functional magnetic resonance imaging (fMRI) and electroencephalography (EEG). However, little is known about how fMRI and EEG measures of spontaneous brain activity are related in ASDs. In the present study, two cohorts of children and adolescents underwent resting-state EEG (n = 38 per group) or fMRI (n = 66 ASD, 57 TD), with a subset of individuals in both the EEG and fMRI cohorts (n = 17 per group). In the EEG cohort, parieto-occipital EEG alpha power was found to be reduced in ASDs. In the fMRI cohort, blood oxygen level-dependent (BOLD) power was regionally increased in right temporal regions and there was widespread overconnectivity between the thalamus and cortical regions in the ASD group relative to the TD group. Finally, multimodal analyses indicated that while TD children showed consistently positive relationships between EEG alpha power and regional BOLD power, these associations were weak or negative in ASDs. These findings suggest atypical links between alpha rhythms and regional BOLD activity in ASDs, possibly implicating neural substrates and processes that coordinate thalamocortical regulation of the alpha rhythm.


Assuntos
Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/fisiopatologia , Adolescente , Ritmo alfa/fisiologia , Transtorno do Espectro Autista/metabolismo , Transtorno Autístico/diagnóstico por imagem , Transtorno Autístico/fisiopatologia , Encéfalo/fisiopatologia , Mapeamento Encefálico/métodos , Criança , Eletroencefalografia/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Tálamo/fisiopatologia
17.
Med Phys ; 47(1): 119-131, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31682019

RESUMO

PURPOSE: To design a multiscale descriptor capable of capturing complex local-regional unfolding patterns to support quantitation and diagnosis of autism spectrum disorders (ASD) using T1-weighted structural magnetic resonance images (MRI) with voxel size of 1 × 1 × 1 mm. METHODS: The proposed image descriptor uses an adapted multiscale representation, the Curvelet transform, interpretable in terms of texture (local) and shape (regional) to characterize brain regions, and a Generalized Gaussian Distribution (GGD) to reduce feature dimensionality. In this approach, each MRI is first parcelled into 3D anatomical regions. Each resultant region is represented by a single 2D image where slices are placed next to each other. Each 2D image is characterized by mapping it to the Curvelet space and each of the different Curvelet sub-bands is described by the set of GGD parameters. To assess the discriminant power of the proposed descriptor, a classification model per brain region was built to differentiate ASD patients from control subjects. Models were constructed with support vector machines and evaluated using two samples from heterogeneous databases, namely Autism Brain Imaging Data Exchange - ABIDE I (34 ASD and 34 controls, mean age 11.46 ± 2.03 and 11.53 ± 1.79 yr, respectively, male population) and ABIDE II (42 ASD and 41 controls, mean age 10.09 ± 1.37 and 10.52 ± 1.27 yr, respectively, male population), for a total of 151 individuals. RESULTS: When the model was trained with ABIDE II sample and tested with ABIDE I on a hold-out validation, an area under receiver operator curve (AUC) of 0.69 was computed. When each sample was independently used under a cross-validation scheme, the estimated AUC was 0.75 ± 0.02 for ABIDE I and 0.77 ± 0.01 for ABIDE II. This analysis determined a set of discriminant regions widely reported in the literature as characteristic of ASD. CONCLUSIONS: The presented image descriptor demonstrated differences at local and regional level when high differences were observed in the Curvelet sub-bands. The method is simple in conceptual terms, robust to several sources of noise, and has a very low computational cost.


Assuntos
Transtorno do Espectro Autista/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Estudos de Casos e Controles , Criança , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino
18.
Neuroimaging Clin N Am ; 30(1): 97-114, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31759576

RESUMO

Autism spectrum disorder (ASD) emerges during early childhood and is marked by a relatively narrow window in which infants transition from exhibiting normative behavioral profiles to displaying the defining features of the ASD phenotype in toddlerhood. Prospective brain imaging studies in infants at high familial risk for autism have revealed important insights into the neurobiology and developmental unfolding of ASD. In this article, we review neuroimaging studies of brain development in ASD from birth through toddlerhood, relate these findings to candidate neurobiological mechanisms, and discuss implications for future research and translation to clinical practice.


Assuntos
Transtorno do Espectro Autista/patologia , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Neuroimagem/métodos , Transtorno do Espectro Autista/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética , Prognóstico , Estudos Prospectivos
19.
BMC Psychiatry ; 19(1): 399, 2019 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-31842898

RESUMO

BACKGROUND: Individuals with autism spectrum disorder (ASD) have social interaction deficits and difficulties in emotional regulation. The neural substrates for these socio-affective deficits are not yet clear, but one potential candidate is maldevelopment of the uncinate fasciculus (UF), a white matter tract thought to be involved in socio-affective processing. However, the developmental trajectory of the UF in young children with social interaction deficits has not been examined. The present study was designed to describe the developmental growth trajectory of the UF and the relationships between UF development and social deficits in ASD. METHODS: Eigenvalues of the UF were measured by diffusion tensor imaging (DTI)-based tractography in 37 children with ASD and 27 matched 2-3-year-old subjects with developmental delay (DD) at baseline (time 1) and at 2-year follow-up (time 2). Growth rates of the UF were compared between groups and associations with social deficit scores according to the Autism Diagnostic Interview-Revised (ADI-R) analyzed by Pearson's correlations. RESULTS: At time 1, axial diffusivity (AD) of the left UF was significantly larger in the ASD group than the DD group. At time 2, left UF fractional anisotropy (FA) was significantly higher and radial diffusivity (RD) significantly lower in the ASD group than the DD group. The rate of UF growth during this 2-year interval was faster in children with ASD than DD. Significant negative correlations were found between the rise in ADI-R social deficit measures and both right UF RD and left UF mean diffusivity (MD). CONCLUSIONS: Young children with ASD demonstrate UF overgrowth during the 2-year development period between 2 and 3 and 4-5 years of age, and this white matter abnormality is directly associated with the progression of social deficits. TRIAL REGISTRATION: World Health Organization class I registered international clinical trial platform, ChiCTR-ROC-17012877.


Assuntos
Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/psicologia , Encéfalo/diagnóstico por imagem , Ajustamento Social , Substância Branca/diagnóstico por imagem , Pré-Escolar , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Masculino , Rede Nervosa/diagnóstico por imagem
20.
Transl Psychiatry ; 9(1): 332, 2019 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-31819038

RESUMO

Autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) share high rates of comorbidity, with the Diagnostic and Statistical Manual of Mental Disorders-Fifth Edition now acknowledging the comorbid diagnosis of ASD and ADHD. Although structural abnormalities in the prefrontal cortex, cerebellum, and basal ganglia occur in both ASD and ADHD, no structural studies have focused exclusively on patients with comorbid ASD and ADHD. We thus aimed to clarify the structural features and developmental changes in patients with comorbid ASD and ADHD in a relatively large sample from two sites. Ninety-two patients were age-matched to 141 typically developing (TD) controls (age range: 5-16 years) and assessed for volumetric characteristics using structural magnetic resonance imaging (i.e. surface-based morphometry). While there were no significant differences in prefrontal cortex, cerebellum, and basal ganglia volumes, patients with ASD and ADHD exhibited significantly lower left postcentral gyrus volumes than TD controls. We observed significantly lower postcentral gyrus volumes exclusively in children and preadolescents, and not in adolescents. Our findings suggest that abnormal somatosensory, attributed to delayed maturation of the left postcentral gyrus, leads to the core symptoms experienced by patients with comorbid ASD and ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/patologia , Transtorno do Espectro Autista/patologia , Córtex Cerebral/patologia , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico por imagem , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/epidemiologia , Córtex Cerebral/diagnóstico por imagem , Criança , Pré-Escolar , Comorbidade , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
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