5 recherche sur le mot-clé 'Diffusion MRI'

A Multimodal Study of the Contributions of Conduction Velocity to the Auditory Evoked Neuromagnetic Response: Anomalies in Autism Spectrum Disorder / Timothy P. L. ROBERTS in Autism Research, 13-10 (October 2020)  

Public ISBD [article]  inAutism Research > 13-10 (October 2020) . - p.1730-1745 Titre : A Multimodal Study of the Contributions of Conduction Velocity to the Auditory Evoked Neuromagnetic Response: Anomalies in Autism Spectrum Disorder Type de document : Texte imprimé et/ou numérique Auteurs : Timothy P. L. ROBERTS, Auteur ; Luke BLOY, Auteur ; Matt KU, Auteur ; Lisa BLASKEY, Auteur ; Carissa R. JACKEL, Auteur ; James Christopher EDGAR, Auteur ; Jeffrey I. BERMAN, Auteur Article en page(s) : p.1730-1745 Langues : Anglais (eng) Mots-clés : MR spectroscopy  autism spectrum disorder  conduction velocity  diffusion MRI  magnetoencephalography  multimodal imaging Index. décimale : PER Périodiques Résumé : This multimodal imaging study used magnetoencephalography, diffusion magnetic resonance imaging (MRI), and gamma-aminobutyric acid (GABA) magnetic resonance spectroscopy (MRS) to identify and contrast the multiple physiological mechanisms associated with auditory processing efficiency in typically developing (TD) children and children with autism spectrum disorder (ASD). Efficient transmission of auditory input between the ear and auditory cortex is necessary for rapid encoding of auditory sensory information. It was hypothesized that the M50 auditory evoked response latency would be modulated by white matter microstructure (indexed by diffusion MRI) and by tonic inhibition (indexed by GABA MRS). Participants were 77 children diagnosed with ASD and 40 TD controls aged 7-17?years. A model of M50 latency with auditory radiation fractional anisotropy and age as independent variables was able to predict 52% of M50 latency variance in TD children, but only 12% of variance in ASD. The ASD group exhibited altered patterns of M50 latency modulation characterized by both higher variance and deviation from the expected structure-function relationship established with the TD group. The TD M50 latency model was used to identify a subpopulation of ASD who are significant "outliers" to the TD model. The ASD outlier group exhibited unexpectedly long M50 latencies in conjunction with significantly lower GABA levels. These findings indicate the dependence of electrophysiologic sensory response latency on underlying microstructure (white matter) and neurochemistry (synaptic activity). This study demonstrates the use of biologically based measures to stratify ASD according to their brain-level "building blocks" as an alternative to their behavioral phenotype. LAY SUMMARY: Children with ASD often have a slower brain response when hearing sounds. This study used multiple brain imaging techniques to examine the structural and neurochemical factors which control the brain's response time to auditory tones in children with ASD and TD children. The relationship between brain imaging measures and brain response time was also used to identify ASD subgroups. Autism Res 2020, 13: 1730-1745. © 2020 International Society for Autism Research and Wiley Periodicals LLC. En ligne : http://dx.doi.org/10.1002/aur.2369 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=431 [article] A Multimodal Study of the Contributions of Conduction Velocity to the Auditory Evoked Neuromagnetic Response: Anomalies in Autism Spectrum Disorder [Texte imprimé et/ou numérique] / Timothy P. L. ROBERTS, Auteur ; Luke BLOY, Auteur ; Matt KU, Auteur ; Lisa BLASKEY, Auteur ; Carissa R. JACKEL, Auteur ; James Christopher EDGAR, Auteur ; Jeffrey I. BERMAN, Auteur . - p.1730-1745. Langues : Anglais (eng) in Autism Research > 13-10 (October 2020) . - p.1730-1745 Mots-clés : MR spectroscopy  autism spectrum disorder  conduction velocity  diffusion MRI  magnetoencephalography  multimodal imaging Index. décimale : PER Périodiques Résumé : This multimodal imaging study used magnetoencephalography, diffusion magnetic resonance imaging (MRI), and gamma-aminobutyric acid (GABA) magnetic resonance spectroscopy (MRS) to identify and contrast the multiple physiological mechanisms associated with auditory processing efficiency in typically developing (TD) children and children with autism spectrum disorder (ASD). Efficient transmission of auditory input between the ear and auditory cortex is necessary for rapid encoding of auditory sensory information. It was hypothesized that the M50 auditory evoked response latency would be modulated by white matter microstructure (indexed by diffusion MRI) and by tonic inhibition (indexed by GABA MRS). Participants were 77 children diagnosed with ASD and 40 TD controls aged 7-17?years. A model of M50 latency with auditory radiation fractional anisotropy and age as independent variables was able to predict 52% of M50 latency variance in TD children, but only 12% of variance in ASD. The ASD group exhibited altered patterns of M50 latency modulation characterized by both higher variance and deviation from the expected structure-function relationship established with the TD group. The TD M50 latency model was used to identify a subpopulation of ASD who are significant "outliers" to the TD model. The ASD outlier group exhibited unexpectedly long M50 latencies in conjunction with significantly lower GABA levels. These findings indicate the dependence of electrophysiologic sensory response latency on underlying microstructure (white matter) and neurochemistry (synaptic activity). This study demonstrates the use of biologically based measures to stratify ASD according to their brain-level "building blocks" as an alternative to their behavioral phenotype. LAY SUMMARY: Children with ASD often have a slower brain response when hearing sounds. This study used multiple brain imaging techniques to examine the structural and neurochemical factors which control the brain's response time to auditory tones in children with ASD and TD children. The relationship between brain imaging measures and brain response time was also used to identify ASD subgroups. Autism Res 2020, 13: 1730-1745. © 2020 International Society for Autism Research and Wiley Periodicals LLC. En ligne : http://dx.doi.org/10.1002/aur.2369 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=431

Transcallosal white matter and cortical gray matter variations in autistic adults aged 30-73 years / Danielle CHRISTENSEN ; Jingying WANG ; Desirae J SHIRLEY ; Ann-Marie ORLANDO ; Regilda A ROMERO ; David E VAILLANCOURT ; Bradley J WILKES ; Stephen A COOMBES ; Zheng WANG in Molecular Autism, 16 (2025)  

Public ISBD [article]  inMolecular Autism > 16 (2025) . - 16 Titre : Transcallosal white matter and cortical gray matter variations in autistic adults aged 30-73 years Type de document : Texte imprimé et/ou numérique Auteurs : Danielle CHRISTENSEN, Auteur ; Jingying WANG, Auteur ; Desirae J SHIRLEY, Auteur ; Ann-Marie ORLANDO, Auteur ; Regilda A ROMERO, Auteur ; David E VAILLANCOURT, Auteur ; Bradley J WILKES, Auteur ; Stephen A COOMBES, Auteur ; Zheng WANG, Auteur Article en page(s) : 16 Langues : Anglais (eng) Mots-clés : Humans  Male  Gray Matter/diagnostic imaging/pathology  White Matter/diagnostic imaging/pathology  Female  Adult  Middle Aged  Aged  Case-Control Studies  Autistic Disorder/diagnostic imaging/pathology  Corpus Callosum/diagnostic imaging/pathology  Autism Spectrum Disorder/diagnostic imaging/pathology  Anisotropy  Diffusion Magnetic Resonance Imaging  Aging  Autism spectrum disorder  Autistic adults  Diffusion MRI  Free water  Free water corrected fractional anisotropy  Free water corrected mean diffusivity  Gray matter  Transcallosal tracts  White matter  in this study were approved by the Institutional Review Board (IRB) at the  University of Florida following the Declaration of Helsinki. The IRB number is  202100659, with an approval date of July 26, 2022. Consent for publication: All  authors have read and approved the submission. Competing interests: The authors  declare no competing interests. Index. décimale : PER Périodiques Résumé : BACKGROUND: Autism spectrum disorder (ASD) is a lifelong condition that profoundly impacts health, independence, and quality of life. However, research on brain aging in autistic adults is limited, and microstructural variations in white and gray matter remain poorly understood. To address this critical gap, we assessed novel diffusion MRI (dMRI) biomarkers, free water, and free water corrected fractional anisotropy (fwcFA), and mean diffusivity (fwcMD) across 32 transcallosal tracts and their corresponding homotopic grey matter origin/endpoint regions of interest (ROIs) in middle and old aged autistic adults. METHODS: Forty-three autistic adults aged 30-73 and 43 age-, sex-, and IQ-matched neurotypical controls underwent dMRI scans. We examined free water, fwcFA, fwcMD differences between the two groups and age-related pattern of each dMRI metric across the whole brain for each group. The relationships between clinical measures of ASD and free water in regions that significantly differentiated autistic adults from neurotypical controls were also explored. In supplementary analyses, we also assessed free water uncorrected FA and MD using conventional single tensor modeling. RESULTS: Autistic adults exhibited significantly elevated free water in seven frontal transcallosal tracts compared to controls. In controls, age-related increases in free water and decreases in fwcFA were observed across most transcallosal tracts. However, these age-associated patterns were entirely absent in autistic adults. In gray matter, autistic adults showed elevated free water in the calcarine cortices and lower fwcMD in the dorsal premotor cortices compared to controls. Lastly, age-related increases in free water were found across all white matter and gray matter ROIs in neurotypical controls, whereas no age-related associations were detected in any dMRI metrics for autistic adults. LIMITATIONS: We only recruited cognitively capable autistic adults, which limits the generalizability of our findings across the full autism spectrum. The cross-sectional design precludes inferences about microstructural changes over time in middle and old aged autistic adults. CONCLUSIONS: Our findings revealed increased free water load in frontal white matter in autistic adults and identified distinct age-associated microstructural variations between the two groups. These findings highlight more heterogeneous brain aging profiles in autistic adults. Our study also demonstrated the importance of quantifying free water in dMRI studies of ASD. En ligne : https://dx.doi.org/10.1186/s13229-025-00652-6 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=555 [article] Transcallosal white matter and cortical gray matter variations in autistic adults aged 30-73 years [Texte imprimé et/ou numérique] / Danielle CHRISTENSEN, Auteur ; Jingying WANG, Auteur ; Desirae J SHIRLEY, Auteur ; Ann-Marie ORLANDO, Auteur ; Regilda A ROMERO, Auteur ; David E VAILLANCOURT, Auteur ; Bradley J WILKES, Auteur ; Stephen A COOMBES, Auteur ; Zheng WANG, Auteur . - 16. Langues : Anglais (eng) in Molecular Autism > 16 (2025) . - 16 Mots-clés : Humans  Male  Gray Matter/diagnostic imaging/pathology  White Matter/diagnostic imaging/pathology  Female  Adult  Middle Aged  Aged  Case-Control Studies  Autistic Disorder/diagnostic imaging/pathology  Corpus Callosum/diagnostic imaging/pathology  Autism Spectrum Disorder/diagnostic imaging/pathology  Anisotropy  Diffusion Magnetic Resonance Imaging  Aging  Autism spectrum disorder  Autistic adults  Diffusion MRI  Free water  Free water corrected fractional anisotropy  Free water corrected mean diffusivity  Gray matter  Transcallosal tracts  White matter  in this study were approved by the Institutional Review Board (IRB) at the  University of Florida following the Declaration of Helsinki. The IRB number is  202100659, with an approval date of July 26, 2022. Consent for publication: All  authors have read and approved the submission. Competing interests: The authors  declare no competing interests. Index. décimale : PER Périodiques Résumé : BACKGROUND: Autism spectrum disorder (ASD) is a lifelong condition that profoundly impacts health, independence, and quality of life. However, research on brain aging in autistic adults is limited, and microstructural variations in white and gray matter remain poorly understood. To address this critical gap, we assessed novel diffusion MRI (dMRI) biomarkers, free water, and free water corrected fractional anisotropy (fwcFA), and mean diffusivity (fwcMD) across 32 transcallosal tracts and their corresponding homotopic grey matter origin/endpoint regions of interest (ROIs) in middle and old aged autistic adults. METHODS: Forty-three autistic adults aged 30-73 and 43 age-, sex-, and IQ-matched neurotypical controls underwent dMRI scans. We examined free water, fwcFA, fwcMD differences between the two groups and age-related pattern of each dMRI metric across the whole brain for each group. The relationships between clinical measures of ASD and free water in regions that significantly differentiated autistic adults from neurotypical controls were also explored. In supplementary analyses, we also assessed free water uncorrected FA and MD using conventional single tensor modeling. RESULTS: Autistic adults exhibited significantly elevated free water in seven frontal transcallosal tracts compared to controls. In controls, age-related increases in free water and decreases in fwcFA were observed across most transcallosal tracts. However, these age-associated patterns were entirely absent in autistic adults. In gray matter, autistic adults showed elevated free water in the calcarine cortices and lower fwcMD in the dorsal premotor cortices compared to controls. Lastly, age-related increases in free water were found across all white matter and gray matter ROIs in neurotypical controls, whereas no age-related associations were detected in any dMRI metrics for autistic adults. LIMITATIONS: We only recruited cognitively capable autistic adults, which limits the generalizability of our findings across the full autism spectrum. The cross-sectional design precludes inferences about microstructural changes over time in middle and old aged autistic adults. CONCLUSIONS: Our findings revealed increased free water load in frontal white matter in autistic adults and identified distinct age-associated microstructural variations between the two groups. These findings highlight more heterogeneous brain aging profiles in autistic adults. Our study also demonstrated the importance of quantifying free water in dMRI studies of ASD. En ligne : https://dx.doi.org/10.1186/s13229-025-00652-6 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=555

White matter microstructural and morphometric alterations in autism: implications for intellectual capabilities / Chun-Hung YEH in Molecular Autism, 13 (2022)  

Public ISBD [article]  inMolecular Autism > 13 (2022) . - 21 p. Titre : White matter microstructural and morphometric alterations in autism: implications for intellectual capabilities Type de document : Texte imprimé et/ou numérique Auteurs : Chun-Hung YEH, Auteur ; Rung-Yu TSENG, Auteur ; Hsing-Chang NI, Auteur ; Luca COCCHI, Auteur ; Jung-Chi CHANG, Auteur ; Mei-Yun HSU, Auteur ; En-Nien TU, Auteur ; Yu-Yu WU, Auteur ; Tai-Li CHOU, Auteur ; Susan Shur-Fen GAU, Auteur ; Hsiang-Yuan LIN, Auteur Article en page(s) : 21 p. Langues : Anglais (eng) Mots-clés : Adolescent  Autism Spectrum Disorder/diagnostic imaging/pathology  Autistic Disorder/diagnostic imaging/pathology  Brain/diagnostic imaging/pathology  Corpus Callosum/diagnostic imaging  Diffusion Magnetic Resonance Imaging/methods  Humans  White Matter/diagnostic imaging/pathology  Autism spectrum disorder  Cerebellum  Diffusion MRI  Fixel-based analysis  Intellectual disabilities  Minimally verbal status Index. décimale : PER Périodiques Résumé : BACKGROUND: Neuroimage literature of autism spectrum disorder (ASD) has a moderate-to-high risk of bias, partially because those combined with intellectual impairment (II) and/or minimally verbal (MV) status are generally ignored. We aimed to provide more comprehensive insights into white matter alterations of ASD, inclusive of individuals with II (ASD-II-Only) or MV expression (ASD-MV). METHODS: Sixty-five participants with ASD (ASD-Whole; 16.6?+?5.9 years; comprising 34 intellectually able youth, ASD-IA, and 31 intellectually impaired youth, ASD-II, including 24 ASD-II-Only plus 7 ASD-MV) and 38 demographic-matched typically developing controls (TDC; 17.3?+?5.6 years) were scanned in accelerated diffusion-weighted MRI. Fixel-based analysis was undertaken to investigate the categorical differences in fiber density (FD), fiber cross section (FC), and a combined index (FDC), and brain symptom/cognition associations. RESULTS: ASD-Whole had reduced FD in the anterior and posterior corpus callosum and left cerebellum Crus I, and smaller FDC in right cerebellum Crus II, compared to TDC. ASD-IA, relative to TDC, had no significant discrepancies, while ASD-II showed almost identical alterations to those from ASD-Whole vs. TDC. ASD-II-Only had greater FD/FDC in the isthmus splenium of callosum than ASD-MV. Autistic severity negatively correlated with FC in right Crus I. Nonverbal full-scale IQ positively correlated with FC/FDC in cerebellum VI. FD/FDC of the right dorsolateral prefrontal cortex showed a diagnosis-by-executive function interaction. LIMITATIONS: We could not preclude the potential effects of age and sex from the ASD cohort, although statistical tests suggested that these factors were not influential. Our results could be confounded by variable psychiatric comorbidities and psychotropic medication uses in our ASD participants recruited from outpatient clinics, which is nevertheless closer to a real-world presentation of ASD. The outcomes related to ASD-MV were considered preliminaries due to the small sample size within this subgroup. Finally, our study design did not include intellectual impairment-only participants without ASD to disentangle the mixture of autistic and intellectual symptoms. CONCLUSIONS: ASD-associated white matter alterations appear driven by individuals with II and potentially further by MV. Results suggest that changes in the corpus callosum and cerebellum are key for psychopathology and cognition associated with ASD. Our work highlights an essential to include understudied subpopulations on the spectrum in research. En ligne : http://dx.doi.org/10.1186/s13229-022-00499-1 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=477 [article] White matter microstructural and morphometric alterations in autism: implications for intellectual capabilities [Texte imprimé et/ou numérique] / Chun-Hung YEH, Auteur ; Rung-Yu TSENG, Auteur ; Hsing-Chang NI, Auteur ; Luca COCCHI, Auteur ; Jung-Chi CHANG, Auteur ; Mei-Yun HSU, Auteur ; En-Nien TU, Auteur ; Yu-Yu WU, Auteur ; Tai-Li CHOU, Auteur ; Susan Shur-Fen GAU, Auteur ; Hsiang-Yuan LIN, Auteur . - 21 p. Langues : Anglais (eng) in Molecular Autism > 13 (2022) . - 21 p. Mots-clés : Adolescent  Autism Spectrum Disorder/diagnostic imaging/pathology  Autistic Disorder/diagnostic imaging/pathology  Brain/diagnostic imaging/pathology  Corpus Callosum/diagnostic imaging  Diffusion Magnetic Resonance Imaging/methods  Humans  White Matter/diagnostic imaging/pathology  Autism spectrum disorder  Cerebellum  Diffusion MRI  Fixel-based analysis  Intellectual disabilities  Minimally verbal status Index. décimale : PER Périodiques Résumé : BACKGROUND: Neuroimage literature of autism spectrum disorder (ASD) has a moderate-to-high risk of bias, partially because those combined with intellectual impairment (II) and/or minimally verbal (MV) status are generally ignored. We aimed to provide more comprehensive insights into white matter alterations of ASD, inclusive of individuals with II (ASD-II-Only) or MV expression (ASD-MV). METHODS: Sixty-five participants with ASD (ASD-Whole; 16.6?+?5.9 years; comprising 34 intellectually able youth, ASD-IA, and 31 intellectually impaired youth, ASD-II, including 24 ASD-II-Only plus 7 ASD-MV) and 38 demographic-matched typically developing controls (TDC; 17.3?+?5.6 years) were scanned in accelerated diffusion-weighted MRI. Fixel-based analysis was undertaken to investigate the categorical differences in fiber density (FD), fiber cross section (FC), and a combined index (FDC), and brain symptom/cognition associations. RESULTS: ASD-Whole had reduced FD in the anterior and posterior corpus callosum and left cerebellum Crus I, and smaller FDC in right cerebellum Crus II, compared to TDC. ASD-IA, relative to TDC, had no significant discrepancies, while ASD-II showed almost identical alterations to those from ASD-Whole vs. TDC. ASD-II-Only had greater FD/FDC in the isthmus splenium of callosum than ASD-MV. Autistic severity negatively correlated with FC in right Crus I. Nonverbal full-scale IQ positively correlated with FC/FDC in cerebellum VI. FD/FDC of the right dorsolateral prefrontal cortex showed a diagnosis-by-executive function interaction. LIMITATIONS: We could not preclude the potential effects of age and sex from the ASD cohort, although statistical tests suggested that these factors were not influential. Our results could be confounded by variable psychiatric comorbidities and psychotropic medication uses in our ASD participants recruited from outpatient clinics, which is nevertheless closer to a real-world presentation of ASD. The outcomes related to ASD-MV were considered preliminaries due to the small sample size within this subgroup. Finally, our study design did not include intellectual impairment-only participants without ASD to disentangle the mixture of autistic and intellectual symptoms. CONCLUSIONS: ASD-associated white matter alterations appear driven by individuals with II and potentially further by MV. Results suggest that changes in the corpus callosum and cerebellum are key for psychopathology and cognition associated with ASD. Our work highlights an essential to include understudied subpopulations on the spectrum in research. En ligne : http://dx.doi.org/10.1186/s13229-022-00499-1 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=477

White Matter and Visuospatial Processing in Autism: A Constrained Spherical Deconvolution Tractography Study / Jane MCGRATH in Autism Research, 6-5 (October 2013)  

Public ISBD [article]  inAutism Research > 6-5 (October 2013) . - p.307-319 Titre : White Matter and Visuospatial Processing in Autism: A Constrained Spherical Deconvolution Tractography Study Type de document : Texte imprimé et/ou numérique Auteurs : Jane MCGRATH, Auteur ; Katherine JOHNSON, Auteur ; Erik O'HANLON, Auteur ; Hugh GARAVAN, Auteur ; Louise GALLAGHER, Auteur ; Alexander LEEMANS, Auteur Article en page(s) : p.307-319 Langues : Anglais (eng) Mots-clés : diffusion MRI  constrained spherical deconvolution  tractography  autism  visuospatial processing  inferior fronto-occipital fasciculus Index. décimale : PER Périodiques Résumé : Autism spectrum disorders (ASDs) are associated with a marked disturbance of neural functional connectivity, which may arise from disrupted organization of white matter. The aim of this study was to use constrained spherical deconvolution (CSD)-based tractography to isolate and characterize major intrahemispheric white matter tracts that are important in visuospatial processing. CSD-based tractography avoids a number of critical confounds that are associated with diffusion tensor tractography, and to our knowledge, this is the first time that this advanced diffusion tractography method has been used in autism research. Twenty-five participants with ASD and aged 25, intelligence quotient-matched controls completed a high angular resolution diffusion imaging scan. The inferior fronto-occipital fasciculus (IFOF) and arcuate fasciculus were isolated using CSD-based tractography. Quantitative diffusion measures of white matter microstructural organization were compared between groups and associated with visuospatial processing performance. Significant alteration of white matter organization was present in the right IFOF in individuals with ASD. In addition, poorer visuospatial processing was associated in individuals with ASD with disrupted white matter in the right IFOF. Using a novel, advanced tractography method to isolate major intrahemispheric white matter tracts in autism, this research has demonstrated that there are significant alterations in the microstructural organization of white matter in the right IFOF in ASD. This alteration was associated with poorer visuospatial processing performance in the ASD group. This study provides an insight into structural brain abnormalities that may influence atypical visuospatial processing in autism. En ligne : http://dx.doi.org/10.1002/aur.1290 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=218 [article] White Matter and Visuospatial Processing in Autism: A Constrained Spherical Deconvolution Tractography Study [Texte imprimé et/ou numérique] / Jane MCGRATH, Auteur ; Katherine JOHNSON, Auteur ; Erik O'HANLON, Auteur ; Hugh GARAVAN, Auteur ; Louise GALLAGHER, Auteur ; Alexander LEEMANS, Auteur . - p.307-319. Langues : Anglais (eng) in Autism Research > 6-5 (October 2013) . - p.307-319 Mots-clés : diffusion MRI  constrained spherical deconvolution  tractography  autism  visuospatial processing  inferior fronto-occipital fasciculus Index. décimale : PER Périodiques Résumé : Autism spectrum disorders (ASDs) are associated with a marked disturbance of neural functional connectivity, which may arise from disrupted organization of white matter. The aim of this study was to use constrained spherical deconvolution (CSD)-based tractography to isolate and characterize major intrahemispheric white matter tracts that are important in visuospatial processing. CSD-based tractography avoids a number of critical confounds that are associated with diffusion tensor tractography, and to our knowledge, this is the first time that this advanced diffusion tractography method has been used in autism research. Twenty-five participants with ASD and aged 25, intelligence quotient-matched controls completed a high angular resolution diffusion imaging scan. The inferior fronto-occipital fasciculus (IFOF) and arcuate fasciculus were isolated using CSD-based tractography. Quantitative diffusion measures of white matter microstructural organization were compared between groups and associated with visuospatial processing performance. Significant alteration of white matter organization was present in the right IFOF in individuals with ASD. In addition, poorer visuospatial processing was associated in individuals with ASD with disrupted white matter in the right IFOF. Using a novel, advanced tractography method to isolate major intrahemispheric white matter tracts in autism, this research has demonstrated that there are significant alterations in the microstructural organization of white matter in the right IFOF in ASD. This alteration was associated with poorer visuospatial processing performance in the ASD group. This study provides an insight into structural brain abnormalities that may influence atypical visuospatial processing in autism. En ligne : http://dx.doi.org/10.1002/aur.1290 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=218

White Matter Microstructure Predicts Autistic Traits in Attention-Deficit/Hyperactivity Disorder / Miriam COOPER in Journal of Autism and Developmental Disorders, 44-11 (November 2014)  

Public ISBD [article]  inJournal of Autism and Developmental Disorders > 44-11 (November 2014) . - p.2742-2754 Titre : White Matter Microstructure Predicts Autistic Traits in Attention-Deficit/Hyperactivity Disorder Type de document : Texte imprimé et/ou numérique Auteurs : Miriam COOPER, Auteur ; Anita THAPAR, Auteur ; Derek K. JONES, Auteur Article en page(s) : p.2742-2754 Langues : Anglais (eng) Mots-clés : Diffusion MRI  ADHD  ASD  White matter  Tract-based spatial statistics  RESTORE Index. décimale : PER Périodiques Résumé : Traits of autism spectrum disorder (ASD) in children with attention-deficit/hyperactivity disorder (ADHD) have previously been found to index clinical severity. This study examined the association of ASD traits with diffusion parameters in adolescent males with ADHD (n = 17), and also compared WM microstructure relative to controls (n = 17). Significant associations (p 0.05, corrected) were found between fractional anisotropy/radial diffusivity and ASD trait severity (positive and negative correlations respectively), mostly in the right posterior limb of the internal capsule/corticospinal tract, right cerebellar peduncle and the midbrain. No case–control differences were found for the diffusion parameters investigated. This is the first report of a WM microstructural signature of autistic traits in ADHD. Thus, even in the absence of full disorder, ASD traits may index a distinctive underlying neurobiology in ADHD. En ligne : http://dx.doi.org/10.1007/s10803-014-2131-9 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=241 [article] White Matter Microstructure Predicts Autistic Traits in Attention-Deficit/Hyperactivity Disorder [Texte imprimé et/ou numérique] / Miriam COOPER, Auteur ; Anita THAPAR, Auteur ; Derek K. JONES, Auteur . - p.2742-2754. Langues : Anglais (eng) in Journal of Autism and Developmental Disorders > 44-11 (November 2014) . - p.2742-2754 Mots-clés : Diffusion MRI  ADHD  ASD  White matter  Tract-based spatial statistics  RESTORE Index. décimale : PER Périodiques Résumé : Traits of autism spectrum disorder (ASD) in children with attention-deficit/hyperactivity disorder (ADHD) have previously been found to index clinical severity. This study examined the association of ASD traits with diffusion parameters in adolescent males with ADHD (n = 17), and also compared WM microstructure relative to controls (n = 17). Significant associations (p 0.05, corrected) were found between fractional anisotropy/radial diffusivity and ASD trait severity (positive and negative correlations respectively), mostly in the right posterior limb of the internal capsule/corticospinal tract, right cerebellar peduncle and the midbrain. No case–control differences were found for the diffusion parameters investigated. This is the first report of a WM microstructural signature of autistic traits in ADHD. Thus, even in the absence of full disorder, ASD traits may index a distinctive underlying neurobiology in ADHD. En ligne : http://dx.doi.org/10.1007/s10803-014-2131-9 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=241