The Experts below are selected from a list of 17082 Experts worldwide ranked by ideXlab platform
Guillaume Marrelec - One of the best experts on this subject based on the ideXlab platform.
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Default-Mode Network Functional Connectivity in Aphasia: Therapy-Induced Neuroplasticity.
Brain and Language, 2012Co-Authors: Karine Marcotte, Vincent Perlbarg, Guillaume Marrelec, Habib Benali, Ana Inés AnsaldoAbstract:Previous research on participants with aphasia has mainly been based on standard functional neuroimaging analysis. Recent studies have shown that functional connectivity analysis can detect compensatory activity, not revealed by standard analysis. Little is known, however, about the Default-Mode Network in aphasia. In the current study, we studied changes in the Default-Mode Network in subjects with aphasia who underwent semantic feature analysis therapy. We studied nine participants with chronic aphasia and compared them to 10 control participants. For the first time, we identified the Default-Mode Network using spatial independent component analysis, in participants with aphasia. Intensive therapy improved integration in the posterior areas of the Default-Mode Network concurrent with language improvement. Correlations between integration and improvement did not reach significance, but the trend suggests that pre-therapy integration of the Default-Mode Network may predict therapy outcomes. Functional connectivity allows a better understanding of the impact of semantic feature analysis in aphasia.
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the precuneus posterior cingulate cortex plays a pivotal role in the Default Mode Network evidence from a partial correlation Network analysis
NeuroImage, 2008Co-Authors: Peter Fransson, Guillaume MarrelecAbstract:Abstract Recent research has shown that intrinsic brain activity as observed by functional magnetic resonance imaging (fMRI) manifest itself as coherent signal changes in Networks encompassing brain regions that span long-range neuronal pathways. One of these Networks, the so called Default Mode Network, has become the primary target in recent investigations to link intrinsic activity to cognition and how intrinsic signal changes may be altered in disease. In this study we assessed functional connectivity within the Default Mode Network during both rest and a continuous working memory task on a region-by-region basis using partial correlation analysis, a data-driven method that provides insight into effective connectivity within neuronal Networks. Prominent features of functional connectivity within the Default Mode Network included an overall strong level of interaction between the precuneus/posterior cingulate region and the rest of the Default Mode Network, as well as a high degree of interaction between the left and right medial temporal lobes combined with weak interactions between the medial temporal lobes and the rest of the Default Mode Network. Additionally, we found support for strong interactions between the precuneus/posterior cingulate cortex and the left inferior parietal lobe as well as between the dorsal and ventral sections of the medial prefrontal cortex. The suggested pivotal role of the precuneus/posterior cingulate cortex in the Default Mode Network is discussed.
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The precuneus/posterior cingulate cortex plays a pivotal role in the Default Mode Network: Evidence from a partial correlation Network analysis
NeuroImage, 2008Co-Authors: Peter Fransson, Guillaume MarrelecAbstract:Abstract Recent research has shown that intrinsic brain activity as observed by functional magnetic resonance imaging (fMRI) manifest itself as coherent signal changes in Networks encompassing brain regions that span long-range neuronal pathways. One of these Networks, the so called Default Mode Network, has become the primary target in recent investigations to link intrinsic activity to cognition and how intrinsic signal changes may be altered in disease. In this study we assessed functional connectivity within the Default Mode Network during both rest and a continuous working memory task on a region-by-region basis using partial correlation analysis, a data-driven method that provides insight into effective connectivity within neuronal Networks. Prominent features of functional connectivity within the Default Mode Network included an overall strong level of interaction between the precuneus/posterior cingulate region and the rest of the Default Mode Network, as well as a high degree of interaction between the left and right medial temporal lobes combined with weak interactions between the medial temporal lobes and the rest of the Default Mode Network. Additionally, we found support for strong interactions between the precuneus/posterior cingulate cortex and the left inferior parietal lobe as well as between the dorsal and ventral sections of the medial prefrontal cortex. The suggested pivotal role of the precuneus/posterior cingulate cortex in the Default Mode Network is discussed.
Winston Chiong - One of the best experts on this subject based on the ideXlab platform.
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the salience Network causally influences Default Mode Network activity during moral reasoning
Brain, 2013Co-Authors: Winston Chiong, Stephen M Wilson, Mark Desposito, Andrew S Kayser, Scott Grossman, Pardis Poorzand, William W Seeley, Bruce L MillerAbstract:Large-scale brain Networks are integral to the coordination of human behaviour, and their anatomy provides insights into the clinical presentation and progression of neurodegenerative illnesses such as Alzheimer’s disease, which targets the Default Mode Network, and behavioural variant frontotemporal dementia, which targets a more anterior salience Network. Although the Default Mode Network is recruited when healthy subjects deliberate about ‘personal’ moral dilemmas, patients with Alzheimer’s disease give normal responses to these dilemmas whereas patients with behavioural variant frontotemporal dementia give abnormal responses to these dilemmas. We hypothesized that this apparent discrepancy between activation- and patient-based studies of moral reasoning might reflect a modulatory role for the salience Network in regulating Default Mode Network activation. Using functional magnetic resonance imaging to characterize Network activity of patients with behavioural variant frontotemporal dementia and healthy control subjects, we present four converging lines of evidence supporting a causal influence from the salience Network to the Default Mode Network during moral reasoning. First, as previously reported, the Default Mode Network is recruited when healthy subjects deliberate about ‘personal’ moral dilemmas, but patients with behavioural variant frontotemporal dementia producing atrophy in the salience Network give abnormally utilitarian responses to these dilemmas. Second, patients with behavioural variant frontotemporal dementia have reduced recruitment of the Default Mode Network compared with healthy control subjects when deliberating about these dilemmas. Third, a Granger causality analysis of functional neuroimaging data from healthy control subjects demonstrates directed functional connectivity from nodes of the salience Network to nodes of the Default Mode Network during moral reasoning. Fourth, this Granger causal influence is diminished in patients with behavioural variant frontotemporal dementia. These findings are consistent with a broader Model in which the salience Network modulates the activity of other large-scale Networks, and suggest a revision to a previously proposed ‘dual-process’ account of moral reasoning. These findings also characterize Network interactions underlying abnormal moral reasoning in frontotemporal dementia, which may serve as a Model for the aberrant judgement and interpersonal behaviour observed in this disease and in other disorders of social function. More broadly, these findings link recent work on the dynamic interrelationships between large-scale brain Networks to observable impairments in dementia syndromes, which may shed light on how diseases that target one Network also alter the function of interrelated Networks. * Abbreviation : FTD : frontotemporal dementia
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The salience Network causally influences Default Mode Network activity during moral reasoning.
Brain : a journal of neurology, 2013Co-Authors: Winston Chiong, Stephen M Wilson, Andrew S Kayser, Pardis Poorzand, William W Seeley, Bruce L Miller, Mark D'esposito, Scott N Grossman, Katherine P RankinAbstract:Large-scale brain Networks are integral to the coordination of human behaviour, and their anatomy provides insights into the clinical presentation and progression of neurodegenerative illnesses such as Alzheimer's disease, which targets the Default Mode Network, and behavioural variant frontotemporal dementia, which targets a more anterior salience Network. Although the Default Mode Network is recruited when healthy subjects deliberate about 'personal' moral dilemmas, patients with Alzheimer's disease give normal responses to these dilemmas whereas patients with behavioural variant frontotemporal dementia give abnormal responses to these dilemmas. We hypothesized that this apparent discrepancy between activation- and patient-based studies of moral reasoning might reflect a modulatory role for the salience Network in regulating Default Mode Network activation. Using functional magnetic resonance imaging to characterize Network activity of patients with behavioural variant frontotemporal dementia and healthy control subjects, we present four converging lines of evidence supporting a causal influence from the salience Network to the Default Mode Network during moral reasoning. First, as previously reported, the Default Mode Network is recruited when healthy subjects deliberate about 'personal' moral dilemmas, but patients with behavioural variant frontotemporal dementia producing atrophy in the salience Network give abnormally utilitarian responses to these dilemmas. Second, patients with behavioural variant frontotemporal dementia have reduced recruitment of the Default Mode Network compared with healthy control subjects when deliberating about these dilemmas. Third, a Granger causality analysis of functional neuroimaging data from healthy control subjects demonstrates directed functional connectivity from nodes of the salience Network to nodes of the Default Mode Network during moral reasoning. Fourth, this Granger causal influence is diminished in patients with behavioural variant frontotemporal dementia. These findings are consistent with a broader Model in which the salience Network modulates the activity of other large-scale Networks, and suggest a revision to a previously proposed 'dual-process' account of moral reasoning. These findings also characterize Network interactions underlying abnormal moral reasoning in frontotemporal dementia, which may serve as a Model for the aberrant judgement and interpersonal behaviour observed in this disease and in other disorders of social function. More broadly, these findings link recent work on the dynamic interrelationships between large-scale brain Networks to observable impairments in dementia syndromes, which may shed light on how diseases that target one Network also alter the function of interrelated Networks.
Bruce L Miller - One of the best experts on this subject based on the ideXlab platform.
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the salience Network causally influences Default Mode Network activity during moral reasoning
Brain, 2013Co-Authors: Winston Chiong, Stephen M Wilson, Mark Desposito, Andrew S Kayser, Scott Grossman, Pardis Poorzand, William W Seeley, Bruce L MillerAbstract:Large-scale brain Networks are integral to the coordination of human behaviour, and their anatomy provides insights into the clinical presentation and progression of neurodegenerative illnesses such as Alzheimer’s disease, which targets the Default Mode Network, and behavioural variant frontotemporal dementia, which targets a more anterior salience Network. Although the Default Mode Network is recruited when healthy subjects deliberate about ‘personal’ moral dilemmas, patients with Alzheimer’s disease give normal responses to these dilemmas whereas patients with behavioural variant frontotemporal dementia give abnormal responses to these dilemmas. We hypothesized that this apparent discrepancy between activation- and patient-based studies of moral reasoning might reflect a modulatory role for the salience Network in regulating Default Mode Network activation. Using functional magnetic resonance imaging to characterize Network activity of patients with behavioural variant frontotemporal dementia and healthy control subjects, we present four converging lines of evidence supporting a causal influence from the salience Network to the Default Mode Network during moral reasoning. First, as previously reported, the Default Mode Network is recruited when healthy subjects deliberate about ‘personal’ moral dilemmas, but patients with behavioural variant frontotemporal dementia producing atrophy in the salience Network give abnormally utilitarian responses to these dilemmas. Second, patients with behavioural variant frontotemporal dementia have reduced recruitment of the Default Mode Network compared with healthy control subjects when deliberating about these dilemmas. Third, a Granger causality analysis of functional neuroimaging data from healthy control subjects demonstrates directed functional connectivity from nodes of the salience Network to nodes of the Default Mode Network during moral reasoning. Fourth, this Granger causal influence is diminished in patients with behavioural variant frontotemporal dementia. These findings are consistent with a broader Model in which the salience Network modulates the activity of other large-scale Networks, and suggest a revision to a previously proposed ‘dual-process’ account of moral reasoning. These findings also characterize Network interactions underlying abnormal moral reasoning in frontotemporal dementia, which may serve as a Model for the aberrant judgement and interpersonal behaviour observed in this disease and in other disorders of social function. More broadly, these findings link recent work on the dynamic interrelationships between large-scale brain Networks to observable impairments in dementia syndromes, which may shed light on how diseases that target one Network also alter the function of interrelated Networks. * Abbreviation : FTD : frontotemporal dementia
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The salience Network causally influences Default Mode Network activity during moral reasoning.
Brain : a journal of neurology, 2013Co-Authors: Winston Chiong, Stephen M Wilson, Andrew S Kayser, Pardis Poorzand, William W Seeley, Bruce L Miller, Mark D'esposito, Scott N Grossman, Katherine P RankinAbstract:Large-scale brain Networks are integral to the coordination of human behaviour, and their anatomy provides insights into the clinical presentation and progression of neurodegenerative illnesses such as Alzheimer's disease, which targets the Default Mode Network, and behavioural variant frontotemporal dementia, which targets a more anterior salience Network. Although the Default Mode Network is recruited when healthy subjects deliberate about 'personal' moral dilemmas, patients with Alzheimer's disease give normal responses to these dilemmas whereas patients with behavioural variant frontotemporal dementia give abnormal responses to these dilemmas. We hypothesized that this apparent discrepancy between activation- and patient-based studies of moral reasoning might reflect a modulatory role for the salience Network in regulating Default Mode Network activation. Using functional magnetic resonance imaging to characterize Network activity of patients with behavioural variant frontotemporal dementia and healthy control subjects, we present four converging lines of evidence supporting a causal influence from the salience Network to the Default Mode Network during moral reasoning. First, as previously reported, the Default Mode Network is recruited when healthy subjects deliberate about 'personal' moral dilemmas, but patients with behavioural variant frontotemporal dementia producing atrophy in the salience Network give abnormally utilitarian responses to these dilemmas. Second, patients with behavioural variant frontotemporal dementia have reduced recruitment of the Default Mode Network compared with healthy control subjects when deliberating about these dilemmas. Third, a Granger causality analysis of functional neuroimaging data from healthy control subjects demonstrates directed functional connectivity from nodes of the salience Network to nodes of the Default Mode Network during moral reasoning. Fourth, this Granger causal influence is diminished in patients with behavioural variant frontotemporal dementia. These findings are consistent with a broader Model in which the salience Network modulates the activity of other large-scale Networks, and suggest a revision to a previously proposed 'dual-process' account of moral reasoning. These findings also characterize Network interactions underlying abnormal moral reasoning in frontotemporal dementia, which may serve as a Model for the aberrant judgement and interpersonal behaviour observed in this disease and in other disorders of social function. More broadly, these findings link recent work on the dynamic interrelationships between large-scale brain Networks to observable impairments in dementia syndromes, which may shed light on how diseases that target one Network also alter the function of interrelated Networks.
Andrew S Kayser - One of the best experts on this subject based on the ideXlab platform.
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the salience Network causally influences Default Mode Network activity during moral reasoning
Brain, 2013Co-Authors: Winston Chiong, Stephen M Wilson, Mark Desposito, Andrew S Kayser, Scott Grossman, Pardis Poorzand, William W Seeley, Bruce L MillerAbstract:Large-scale brain Networks are integral to the coordination of human behaviour, and their anatomy provides insights into the clinical presentation and progression of neurodegenerative illnesses such as Alzheimer’s disease, which targets the Default Mode Network, and behavioural variant frontotemporal dementia, which targets a more anterior salience Network. Although the Default Mode Network is recruited when healthy subjects deliberate about ‘personal’ moral dilemmas, patients with Alzheimer’s disease give normal responses to these dilemmas whereas patients with behavioural variant frontotemporal dementia give abnormal responses to these dilemmas. We hypothesized that this apparent discrepancy between activation- and patient-based studies of moral reasoning might reflect a modulatory role for the salience Network in regulating Default Mode Network activation. Using functional magnetic resonance imaging to characterize Network activity of patients with behavioural variant frontotemporal dementia and healthy control subjects, we present four converging lines of evidence supporting a causal influence from the salience Network to the Default Mode Network during moral reasoning. First, as previously reported, the Default Mode Network is recruited when healthy subjects deliberate about ‘personal’ moral dilemmas, but patients with behavioural variant frontotemporal dementia producing atrophy in the salience Network give abnormally utilitarian responses to these dilemmas. Second, patients with behavioural variant frontotemporal dementia have reduced recruitment of the Default Mode Network compared with healthy control subjects when deliberating about these dilemmas. Third, a Granger causality analysis of functional neuroimaging data from healthy control subjects demonstrates directed functional connectivity from nodes of the salience Network to nodes of the Default Mode Network during moral reasoning. Fourth, this Granger causal influence is diminished in patients with behavioural variant frontotemporal dementia. These findings are consistent with a broader Model in which the salience Network modulates the activity of other large-scale Networks, and suggest a revision to a previously proposed ‘dual-process’ account of moral reasoning. These findings also characterize Network interactions underlying abnormal moral reasoning in frontotemporal dementia, which may serve as a Model for the aberrant judgement and interpersonal behaviour observed in this disease and in other disorders of social function. More broadly, these findings link recent work on the dynamic interrelationships between large-scale brain Networks to observable impairments in dementia syndromes, which may shed light on how diseases that target one Network also alter the function of interrelated Networks. * Abbreviation : FTD : frontotemporal dementia
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The salience Network causally influences Default Mode Network activity during moral reasoning.
Brain : a journal of neurology, 2013Co-Authors: Winston Chiong, Stephen M Wilson, Andrew S Kayser, Pardis Poorzand, William W Seeley, Bruce L Miller, Mark D'esposito, Scott N Grossman, Katherine P RankinAbstract:Large-scale brain Networks are integral to the coordination of human behaviour, and their anatomy provides insights into the clinical presentation and progression of neurodegenerative illnesses such as Alzheimer's disease, which targets the Default Mode Network, and behavioural variant frontotemporal dementia, which targets a more anterior salience Network. Although the Default Mode Network is recruited when healthy subjects deliberate about 'personal' moral dilemmas, patients with Alzheimer's disease give normal responses to these dilemmas whereas patients with behavioural variant frontotemporal dementia give abnormal responses to these dilemmas. We hypothesized that this apparent discrepancy between activation- and patient-based studies of moral reasoning might reflect a modulatory role for the salience Network in regulating Default Mode Network activation. Using functional magnetic resonance imaging to characterize Network activity of patients with behavioural variant frontotemporal dementia and healthy control subjects, we present four converging lines of evidence supporting a causal influence from the salience Network to the Default Mode Network during moral reasoning. First, as previously reported, the Default Mode Network is recruited when healthy subjects deliberate about 'personal' moral dilemmas, but patients with behavioural variant frontotemporal dementia producing atrophy in the salience Network give abnormally utilitarian responses to these dilemmas. Second, patients with behavioural variant frontotemporal dementia have reduced recruitment of the Default Mode Network compared with healthy control subjects when deliberating about these dilemmas. Third, a Granger causality analysis of functional neuroimaging data from healthy control subjects demonstrates directed functional connectivity from nodes of the salience Network to nodes of the Default Mode Network during moral reasoning. Fourth, this Granger causal influence is diminished in patients with behavioural variant frontotemporal dementia. These findings are consistent with a broader Model in which the salience Network modulates the activity of other large-scale Networks, and suggest a revision to a previously proposed 'dual-process' account of moral reasoning. These findings also characterize Network interactions underlying abnormal moral reasoning in frontotemporal dementia, which may serve as a Model for the aberrant judgement and interpersonal behaviour observed in this disease and in other disorders of social function. More broadly, these findings link recent work on the dynamic interrelationships between large-scale brain Networks to observable impairments in dementia syndromes, which may shed light on how diseases that target one Network also alter the function of interrelated Networks.
Myrna M Weissman - One of the best experts on this subject based on the ideXlab platform.
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increased Default Mode Network connectivity in individuals at high familial risk for depression
Neuropsychopharmacology, 2016Co-Authors: Jonathan Posner, Zhishun Wang, Ardesheer Talati, Virginia Warner, Andrew J Gerber, Bradley S Peterson, Myrna M WeissmanAbstract:Increased Default Mode Network Connectivity in Individuals at High Familial Risk for Depression
