Disrupted Functional Connectivity in Dorsal and Ventral Attention Networks During Attention Orienting in Autism Spectrum Disorders / Jacqueline FITZGERALD in Autism Research, 8-2 (April 2015)  

Public ISBD [article]  inAutism Research > 8-2 (April 2015) . - p.136-152 Titre : Disrupted Functional Connectivity in Dorsal and Ventral Attention Networks During Attention Orienting in Autism Spectrum Disorders Type de document : Texte imprimé et/ou numérique Auteurs : Jacqueline FITZGERALD, Auteur ; Katherine JOHNSON, Auteur ; Elizabeth KEHOE, Auteur ; Arun L. W. BOKDE, Auteur ; Hugh GARAVAN, Auteur ; Louise GALLAGHER, Auteur ; Jane MCGRATH, Auteur Article en page(s) : p.136-152 Langues : Anglais (eng) Mots-clés : autism spectrum disorders  functional connectivity  attention orienting  attention network  neuroimaging Index. décimale : PER Périodiques Résumé : Background Attention orienting is a cognitive process that facilitates the movement of attention focus from one location to another: this may be impaired in autism spectrum disorder (ASD). Dorsal and ventral attention networks (DAN and VAN) sub-serve the process of attention orienting. This study investigated the functional connectivity of attention orienting in these networks in ASD using the Posner Cueing Task. Method Twenty-one adolescents with ASD and 21 age and IQ matched controls underwent functional magnetic resonance imaging. A psychophysical interaction (PPI) analysis was implemented to investigate task-dependent functional connectivity, measuring synchronicity of brain regions during the task. Regions of interest (ROI) were selected to explore functional connectivity in the DAN during cue-only conditions and in the VAN during invalid and valid trials. Results Behaviourally, the ASD and control groups performed the task in a similar manner. Functional MRI results indicated that the ASD and control groups activated similar brain regions. During invalid trials (VAN), the ASD group showed significant positive functional connectivity to multiple brain regions, whilst the control group demonstrated negative connectivity. During valid trials (VAN), the two groups also showed contrasting patterns of connectivity. In the cue-only conditions (DAN), the ASD group showed weaker functional connectivity. Conclusion The DAN analysis suggests that the ASD group has weaker coherence between brain areas involved in goal-driven, endogenous attention control. The strong positive functional connectivity exhibited by the ASD group in the VAN during the invalid trials suggests that individuals with ASD may generate compensatory mechanisms to achieve neurotypical behaviour. These results support the theory of abnormal cortical connectivity in autism. En ligne : http://dx.doi.org/10.1002/aur.1430 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=256 [article] Disrupted Functional Connectivity in Dorsal and Ventral Attention Networks During Attention Orienting in Autism Spectrum Disorders [Texte imprimé et/ou numérique] / Jacqueline FITZGERALD, Auteur ; Katherine JOHNSON, Auteur ; Elizabeth KEHOE, Auteur ; Arun L. W. BOKDE, Auteur ; Hugh GARAVAN, Auteur ; Louise GALLAGHER, Auteur ; Jane MCGRATH, Auteur . - p.136-152. Langues : Anglais (eng) in Autism Research > 8-2 (April 2015) . - p.136-152 Mots-clés : autism spectrum disorders  functional connectivity  attention orienting  attention network  neuroimaging Index. décimale : PER Périodiques Résumé : Background Attention orienting is a cognitive process that facilitates the movement of attention focus from one location to another: this may be impaired in autism spectrum disorder (ASD). Dorsal and ventral attention networks (DAN and VAN) sub-serve the process of attention orienting. This study investigated the functional connectivity of attention orienting in these networks in ASD using the Posner Cueing Task. Method Twenty-one adolescents with ASD and 21 age and IQ matched controls underwent functional magnetic resonance imaging. A psychophysical interaction (PPI) analysis was implemented to investigate task-dependent functional connectivity, measuring synchronicity of brain regions during the task. Regions of interest (ROI) were selected to explore functional connectivity in the DAN during cue-only conditions and in the VAN during invalid and valid trials. Results Behaviourally, the ASD and control groups performed the task in a similar manner. Functional MRI results indicated that the ASD and control groups activated similar brain regions. During invalid trials (VAN), the ASD group showed significant positive functional connectivity to multiple brain regions, whilst the control group demonstrated negative connectivity. During valid trials (VAN), the two groups also showed contrasting patterns of connectivity. In the cue-only conditions (DAN), the ASD group showed weaker functional connectivity. Conclusion The DAN analysis suggests that the ASD group has weaker coherence between brain areas involved in goal-driven, endogenous attention control. The strong positive functional connectivity exhibited by the ASD group in the VAN during the invalid trials suggests that individuals with ASD may generate compensatory mechanisms to achieve neurotypical behaviour. These results support the theory of abnormal cortical connectivity in autism. En ligne : http://dx.doi.org/10.1002/aur.1430 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=256

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

---

1 (1 - 2 / 2)