References of "Soddu, Andrea"
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See detailA multiscale method for a robust detection of the default mode network.
Baquero, Katherine; Gómez, Francisco; Cifuentes, Christian et al

Poster (2013)

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See detailAltered network properties of the fronto-parietal network and the thalamus in impaired consciousness
Crone, Julia Sophia; Soddu, Andrea ULg; Höller, Yvonne et al

in NeuroImage: Clinical (2013)

Recovery of consciousness has been associated with connectivity in the frontal cortex and parietal regions modulated by the thalamus. To examine this model and to relate alterations to deficits in ... [more ▼]

Recovery of consciousness has been associated with connectivity in the frontal cortex and parietal regions modulated by the thalamus. To examine this model and to relate alterations to deficits in cognitive functioning and conscious processing, we investigated topological network properties in patients with chronic disorders of consciousness recovered from coma. Resting state fMRI data of 34 patients with unresponsive wakefulness syndrome and 25 in minimally conscious state were compared to 28 healthy controls.We investigated global and local network characteristics. Additionally, behavioralmeasureswere correlatedwith the localmetrics of 28 regionswithin the fronto-parietal network and the thalamus. In chronic disorders of consciousness, modularity at the global level was reduced suggesting a disturbance in the optimal balance between segregation and integration.Moreover, network properties were altered in several regionswhich are associatedwith conscious processing (particularly, inmedial parietal, and frontal regions, aswell as in the thalamus). Between minimally conscious and unconscious patients the local efficiency of medial parietal regions differed. Alterations in the thalamus were particularly evident in non-conscious patients.Most of the regions affected in patientswith impaired consciousness belong to the so-called ‘rich club’ of highly interconnected central nodes. Disturbances in their topological characteristics have severe impact on information integration and are reflected in deficits in cognitive functioning probably leading to a total breakdown of consciousness. [less ▲]

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See detailThalamus, Brainstem and Salience Network Connectivity Changes During Propofol-Induced Sedation and Unconsciousness
Guldenmund, Justus Pieter ULg; Demertzi, Athina ULg; BOVEROUX, Pierre ULg et al

in Brain connectivity (2013), 3

In this functional magnetic resonance imaging study, we examined the effect of mild propofol sedation and propofol-induced unconsciousness on resting state brain connectivity, using graph analysis based ... [more ▼]

In this functional magnetic resonance imaging study, we examined the effect of mild propofol sedation and propofol-induced unconsciousness on resting state brain connectivity, using graph analysis based on independent component analysis and a classical seed-based analysis. Contrary to previous propofol research, which mainly emphasized the importance of connectivity in the default mode network (DMN) and external control network (ECN), we focused on the salience network, thalamus, and brainstem. The importance of these brain regions in brain arousal and organization merits a more detailed examination of their connectivity response to propofol. We found that the salience network disintegrated during propofol-induced unconsciousness. The thalamus decreased connectivity with the DMN, ECN, and salience network, while increasing connectivity with sensorimotor and auditory/insular cortices. Brainstem regions disconnected from the DMN with unconsciousness, while the pontine tegmental area increased connectivity with the insulae during mild sedation. These findings illustrate that loss of consciousness is associated with a wide variety of decreases and increases of both cortical and subcortical connectivity. It furthermore stresses the necessity of also examining resting state connectivity in networks representing arousal, not only those associated with awareness. [less ▲]

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See detailThe neuroscience of tinnitus: Perspectives from human neuroimaging studies
Maudoux, Audrey ULg; Vanneste, Sven; De Ridder, Dirk et al

Conference (2012, November)

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See detailFunctional connectivity changes in hypnotic state measured by fMRI
Demertzi, Athina ULg; Soddu, Andrea ULg; VANHAUDENHUYSE, Audrey ULg et al

Conference (2012, September 06)

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See detailGlobal breakdown in resting state networks fMRI connectivity in patients with disorders of consciousness
Demertzi, Athina ULg; Soddu, Andrea ULg; VANHAUDENHUYSE, Audrey ULg et al

Conference (2012, July 05)

Patients with disorders of consciousness (DOC: brain death, coma, vegetative/unresponsive, minimally conscious state) show reduced resting state fMRI connectivity in a default mode network as a function ... [more ▼]

Patients with disorders of consciousness (DOC: brain death, coma, vegetative/unresponsive, minimally conscious state) show reduced resting state fMRI connectivity in a default mode network as a function of the level of consciousness.1, 2 Here, we aimed to assess resting state fMRI connectivity in multiple cerebral networks. We further aimed to correlate clinical ͞pain͟scales scores (i.e., Nociception Coma Scale, NCS3) with the functional integrity of the pain-related salience network4 because the issue of pain in DOC is of particular ethical interest.5Methods: 300 fMRI resting state scans were obtained in 28 patients (11 minimally conscious, 12 "vegetative͟/unresponsive, 5 coma) and 22 controls. Seven seed regions were used to identify functional connectivity in the default mode, left and right frontoparietal, salience, sensorimotor, auditory, and visual networks. For salience network, a regression analysis was performed with patients’NCS total score. Results: A group-level correlation between resting state functional connectivity and the level of consciousness was identified for all studied networks. Additionally, patients’ NCS scores showed a positive correlation with functional connectivity in the salience network’s anterior cingulate cortex (ACC). Conclusions: We observed group-level functional connectivity decreases in both primary (visual, auditory) and higher-order associative networks (default mode, right and left fronto-parietal, salience, sensorimotor) possibly accounting for patients diminished consciousness capacities.6 The observed positive correlation between the NCS scores and ACC salience network activity reflects nociception-related processes in these patients measured in the absence of an external stimulus. Our results emphasize the clinical importance of multiple fMRI resting state networks to consciousness. References 1. Boly M, et al. (2009). Hum Brain Mapp 30:2393-2400.2. Vanhaudenhuyse A, et al. (2009). Brain 133:161-171. 3. Schnakers C, et al. (2010). Pain 148:215-219.4. Ploner M, et al. (2010). Proc Natl Acad Sci U S A 107:355-360.5. Demertzi A, et al. (2012). Neuroethics:1-14.6. Baars B, et al. (2003). Trends Neurosci 26:671-675. Preference: Talk Track: Clinical [less ▲]

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See detailInvestigating the tinnitus brain using resting-state fMRI
Maudoux, Audrey ULg; Vanneste, Sven; De Ridder, Dirk et al

Conference (2012, June)

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See detailAuditory Resting-State Network Connectivity in Tinnitus: a Functionnal MRI Study.
MAUDOUX, Audrey ULg; LEFEBVRE, Philippe ULg; CABAY, Jean-Evrard ULg et al

in PLoS ONE (2012)

The underlying functional neuroanatomy of tinnitus remains poorly understood. Few studies have focused on functional cerebral connectivity changes in tinnitus patients. The aim of this study was to test ... [more ▼]

The underlying functional neuroanatomy of tinnitus remains poorly understood. Few studies have focused on functional cerebral connectivity changes in tinnitus patients. The aim of this study was to test if functional MRI ‘‘resting-state’’ connectivity patterns in auditory network differ between tinnitus patients and normal controls. Thirteen chronic tinnitus subjects and fifteen age-matched healthy controls were studied on a 3 tesla MRI. Connectivity was investigated using independent component analysis and an automated component selection approach taking into account the spatial and temporal properties of each component. Connectivity in extra-auditory regions such as brainstem, basal ganglia/NAc, cerebellum, parahippocampal, right prefrontal, parietal, and sensorimotor areas was found to be increased in tinnitus subjects. The right primary auditory cortex, left prefrontal, left fusiform gyrus, and bilateral occipital regions showed a decreased connectivity in tinnitus. These results show that there is a modification of cortical and subcortical functional connectivity in tinnitus encompassing attentional, mnemonic, and emotional networks. Our data corroborate the hypothesized implication of non-auditory regions in tinnitus physiopathology and suggest that various regions of the brain seem involved in the persistent awareness of the phenomenon as well as in the development of the associated distress. leading to disabling chronic tinnitus. [less ▲]

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See detailResting state networks and consciousness Alterations of multiple resting state network connectivity in physiological, pharmacological and pathological consciousness states
Heine, Lizette ULg; Soddu, Andrea ULg; Gomez, Francisco et al

in Frontiers in Psychology (2012), 3

In order to better understand the functional contribution of resting state activity to conscious cognition, we aimed to review increases and decreases in fMRI functional connectivity under physiological ... [more ▼]

In order to better understand the functional contribution of resting state activity to conscious cognition, we aimed to review increases and decreases in fMRI functional connectivity under physiological (sleep), pharmacological (anesthesia) and pathological altered states of consciousness, such as brain death, coma, vegetative state/unresponsive wakefulness syndrome, and minimally conscious state. The reviewed RSNs were the DMN, left and right executive control, salience, sensorimotor, auditory and visual networks. We highlight some methodological issues concerning resting state analyses in severely injured brains mainly in terms of hypothesis-driven seed-based correlation analysis and data-driven independent components analysis approaches. Finally, we attempt to contextualize our discussion within theoretical frameworks of conscious processes. We think that this “lesion” approach allows us to better determine the necessary conditions under which normal conscious cognition takes place. At the clinical level, we acknowledge the technical merits of the resting state paradigm. Indeed, fast and easy acquisitions are preferable to activation paradigms in clinical populations. Finally, we emphasize the need to validate the diagnostic and prognostic value of fMRI resting state measurements in non-communicating brain damaged patients. [less ▲]

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See detailIdentifying the default-mode component in spatial IC analyses of patients with disorders of consciousness.
Soddu, Andrea ULg; Vanhaudenhuyse, Audrey ULg; Bahri, Mohamed Ali ULg et al

in Human Brain Mapping (2012), 36

Objectives:Recent fMRI studies have shown that it is possible to reliably identify the default-mode network (DMN) in the absence of any task, by resting-state connectivity analyses in healthy volunteers ... [more ▼]

Objectives:Recent fMRI studies have shown that it is possible to reliably identify the default-mode network (DMN) in the absence of any task, by resting-state connectivity analyses in healthy volunteers. We here aimed to identify the DMN in the challenging patient population of disorders of consciousness encountered following coma. Experimental design: A spatial independent component analysis-based methodology permitted DMN assessment, decomposing connectivity in all its different sources either neuronal or artifactual. Three different selection criteria were introduced assessing anticorrelation-corrected connectivity with or without an automatic masking procedure and calculating connectivity scores encompassing both spatial and temporal properties. These three methods were validated on 10 healthy controls and applied to an independent group of 8 healthy controls and 11 severely brain-damaged patients [locked-in syndrome (n = 2), minimally conscious (n = 1), and vegetative state (n = 8)]. Principal observations: All vegetative patients showed fewer connections in the default-mode areas, when compared with controls, contrary to locked-in patients who showed near-normal connectivity. In the minimally conscious-state patient, only the two selection criteria considering both spatial and temporal properties were able to identify an intact right lateralized BOLD connectivity pattern, and metabolic PET data suggested its neuronal origin. Conclusions: When assessing resting-state connectivity in patients with disorders of consciousness, it is important to use a methodology excluding non-neuronal contributions caused by head motion, respiration, and heart rate artifacts encountered in all studied patients. Hum Brain Mapp, 2011. (c) 2011 Wiley-Liss, Inc. [less ▲]

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See detailFunctional imaging and impaired consciousness
Vanhaudenhuyse, Audrey ULg; Boly, Mélanie ULg; Bruno, Marie-Aurélie ULg et al

in Schnakers, Caroline; Laureys, Steven (Eds.) Coma and disorders of consciousness (2012)

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See detailSpectroscopy and diffusion tensor imaging in disorders of consciousness
TSHIBANDA, Luaba ULg; Demertzi, Athina ULg; Soddu, Andrea ULg

in Schnakers, C; Laureys, Steven (Eds.) Coma and disorders of consciousness (2012)

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See detailPropofol induced unconsciousness: fMRI total neuronal activity and resting state networks.
Gantner, Ithabi; Guldenmund, Justus Pieter ULg; Gómez, Francisco et al

Poster (2012)

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See detailA default mode of brain function in altered states of consciousness.
Guldenmund, Justus Pieter; Vanhaudenhuyse, Audrey ULg; Boly, Mélanie ULg et al

in Archives Italiennes de Biologie (2012), 150(2-3), 107-21

Using modern brain imaging techniques, new discoveries are being made concerning the spontaneous activity of the brain when it is devoid of attention-demanding tasks. Spatially separated patches of ... [more ▼]

Using modern brain imaging techniques, new discoveries are being made concerning the spontaneous activity of the brain when it is devoid of attention-demanding tasks. Spatially separated patches of neuronal assemblies have been found to show synchronized oscillatory activity behavior and are said to be functionally connected. One of the most robust of these is the default mode network, which is associated with intrinsic processes like mind wandering and self-projection. Furthermore, activity in this network is anticorrelated with activity in a network that is linked to attention to external stimuli. The integrity of both networks is disturbed in altered states of consciousness, like sleep, general anesthesia and hypnosis. In coma and related disorders of consciousness, encompassing the vegetative state (unresponsive wakefulness syndrome) and minimally conscious state, default mode network integrity correlates with the level of remaining consciousness, offering the possibility of using this information for diagnostic and prognostic purposes. Functional brain imaging is currently being validated as a valuable addition to the standardized behavioral assessments that are already in use. [less ▲]

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