References of "Gosseries, Olivia"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailComa and disorders of consciousness: scientific advances and practical considerations for clinicians
Bodart, Olivier ULg; Laureys, Steven ULg; Gosseries, Olivia ULg

in Seminars in Neurology (2013), 33

Recently, neuroscientists and clinicians have seen the rapid evolution of diagnoses in disorders of consciousness. The unresponsive wakefulness syndrome–vegetative state, the minimally conscious state ... [more ▼]

Recently, neuroscientists and clinicians have seen the rapid evolution of diagnoses in disorders of consciousness. The unresponsive wakefulness syndrome–vegetative state, the minimally conscious state plus and minus, and the functional locked-in syndrome have been defined using new neuroimaging techniques. Diffusion tensor imaging, positron emission tomography, functional magnetic resonance imaging, electroen- cephalography, and transcranial magnetic stimulation techniques have all promoted important discoveries in the field of disorders of consciousness. This has led to a better understanding of these patients’ condition and to the development of new prognosis, therapeutic, and communication tools. However, low sensitivity and artifacts problems need to be solved to bring these new technologies to the single-patient level; they also need to be studied in larger scale and randomized control trials. In addition, new ethics questions have arisen and need to be investigated. [less ▲]

Detailed reference viewed: 25 (5 ULg)
Full Text
Peer Reviewed
See detailSpasticity after stroke: Physiology, assessment and treatment
Thibaut, Aurore ULg; Chatelle, Camille ULg; Ziegler, Erik ULg et al

in Brain Injury (2013), 27(10), 1093-1105

Spasticity following a stroke occurs in about 30% of patients. The mechanisms underlying this disorder, however, are not well understood. This review aims to define spasticity, describe hypotheses ... [more ▼]

Spasticity following a stroke occurs in about 30% of patients. The mechanisms underlying this disorder, however, are not well understood. This review aims to define spasticity, describe hypotheses explaining its development after a stroke, give an overview of related neuroimaging studies as well as a description of the most common scales used to quantify the degree of spasticity and finally explore which treatments are currently being used to treat this disorder. The lack of consensus is highlighted on the basis of spasticity and the associated absence of guidelines for treatment, use of drugs and rehabilitation programmes. Future studies require controlled protocols to determine the efficiency of pharmacological and non-pharmacological treatments for spasticity. Neuroimaging may help predict the occurrence of spasticity and could provide insight into its neurological basis. [less ▲]

Detailed reference viewed: 144 (16 ULg)
Full Text
Peer Reviewed
See detailFunctional neuroanatomy of disorders of consciousness
Di Perri, Carol; Stender, Johan; Laureys, Steven ULg et al

in CAVANNA, Andrea (Ed.) Epilepsy and behavior Alteration of Counsciousness in Epilepsy (2013)

Our understanding of the mechanisms of loss and recovery of consciousness, following severe brain injury or during anesthesia, is changing rapidly. Recent neuroimaging studies have shown that patients ... [more ▼]

Our understanding of the mechanisms of loss and recovery of consciousness, following severe brain injury or during anesthesia, is changing rapidly. Recent neuroimaging studies have shown that patients with chronic disorders of consciousness and subjects undergoing general anesthesia present a complex dysfunctionality in the architecture of brain connectivity. At present, the global hallmark of impaired consciousness appears to be amultifaceted dysfunctional connectivity pattern with both within-network loss of connectivity in awidespread frontoparietal network and between-network hyperconnectivity involving other regions such as the insula and ventral tegmental area. Despite ongoing efforts, the mechanisms underlying the emergence of consciousness after severe brain injury are not thoroughly understood. Important questions remain unanswered:What triggers the connectivity impairment leading to disorders of consciousness? Why do some patients recover from coma, while others with apparently similar brain injuries do not? Understanding these mechanisms could lead to a better comprehension of brain function and, hopefully, lead to new therapeutic strategies in this challenging patient population. [less ▲]

Detailed reference viewed: 21 (1 ULg)
Full Text
Peer Reviewed
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 ▲]

Detailed reference viewed: 33 (11 ULg)
Full Text
Peer Reviewed
See detailProbing command following in patients with disorders of consciousness using a brain-computer interface.
Lule, Dorothee; Noirhomme, Quentin ULg; Kleih, Sonja C. et al

in Clinical Neurophysiology (2013), 124(1), 101-6

OBJECTIVE: To determine if brain-computer interfaces (BCIs) could serve as supportive tools for detecting consciousness in patients with disorders of consciousness by detecting response to command and ... [more ▼]

OBJECTIVE: To determine if brain-computer interfaces (BCIs) could serve as supportive tools for detecting consciousness in patients with disorders of consciousness by detecting response to command and communication. METHODS: We tested a 4-choice auditory oddball EEG-BCI paradigm on 16 healthy subjects and 18 patients in a vegetative state/unresponsive wakefulness syndrome, in a minimally conscious state (MCS), and in locked-in syndrome (LIS). Subjects were exposed to 4 training trials and 10 -12 questions. RESULTS: Thirteen healthy subjects and one LIS patient were able to communicate using the BCI. Four of those did not present with a P3. One MCS patient showed command following with the BCI while no behavioral response could be detected at bedside. All other patients did not show any response to command and could not communicate with the BCI. CONCLUSION: The present study provides evidence that EEG based BCI can detect command following in patients with altered states of consciousness and functional communication in patients with locked-in syndrome. However, BCI approaches have to be simplified to increase sensitivity. SIGNIFICANCE: For some patients without any clinical sign of consciousness, a BCI might bear the potential to employ a "yes-no" spelling device offering the hope of functional interactive communication. [less ▲]

Detailed reference viewed: 150 (18 ULg)
Full Text
Peer Reviewed
See detailPain perception in disorders of consciousness: neuroscience, clinical care, and ethics in dialogue
Demertzi, Athina ULg; Racine, Eric; Bruno, Marie-Aurélie ULg et al

in Neuroethics (2013), 6(1), 37-50

Pain, suffering and positive emotions in patients in vegetative state/unresponsive wakefulness syndrome (VS/UWS) and minimally conscious states (MCS) pose clinical and ethical challenges. Clinically, we ... [more ▼]

Pain, suffering and positive emotions in patients in vegetative state/unresponsive wakefulness syndrome (VS/UWS) and minimally conscious states (MCS) pose clinical and ethical challenges. Clinically, we evaluate behavioural responses after painful stimulation and also emotionally-contingent behaviours (e.g., smiling). Using stimuli with emotional valence, neuroimaging and electrophysiology technologies can detect subclinical remnants of preserved capacities for pain which might influence decisions about treatment limitation. To date, no data exist as to how healthcare providers think about end-of-life options (e.g., withdrawal of artificial nutrition and hydration) in the presence or absence of pain in non-communicative patients. Here, we aimed to better clarify this issue by re-analyzing previously published data on pain perception (Prog Brain Res 2009 177, 329–38) and end-of-life decisions (J Neurol 2010 258, 1058–65) in patients with disorders of consciousness. In a sample of 2259 European healthcare professionals we found that, for VS/UWS more respondents agreed with treatment withdrawal when they considered that VS/UWS patients did not feel pain (77%) as compared to those who thought VS/UWS did feel pain (59%). This interaction was influenced by religiosity and professional background. For MCS, end-of-life attitudes were not influenced by opinions on pain perception. Within a contemporary ethical context we discuss (1) the evolving scientific understandings of pain perception and their relationship to existing clinical and ethical guidelines; (2) the discrepancies of attitudes within (and between) healthcare providers and their consequences for treatment approaches, and (3) the implicit but complex relationship between pain perception and attitudes toward life-sustaining treatments. [less ▲]

Detailed reference viewed: 18 (1 ULg)
Full Text
Peer Reviewed
See detailPain perception in disorders of consciousness: Neuroscience, clinical care, and ethics in dialogue
Demertzi, Athina ULg; Racine, Eric; Bruno, Marie-Aurélie ULg et al

in Neuroethics (2012)

Pain, suffering and positive emotions in patients in vegetative state/unresponsive wakefulness syndrome (VS/UWS) and minimally conscious states (MCS) pose clinical and ethical challenges. Clinically, we ... [more ▼]

Pain, suffering and positive emotions in patients in vegetative state/unresponsive wakefulness syndrome (VS/UWS) and minimally conscious states (MCS) pose clinical and ethical challenges. Clinically, we evaluate behavioural responses after painful stimulation and also emotionally-contingent behaviours (e.g., smiling). Using stimuli with emotional valence, neuroimaging and electrophysiology technologies can detect subclinical remnants of preserved capacities for pain which might influence decisions about treatment limitation. To date, no data exist as to how healthcare providers think about end-of-life options (e.g., withdrawal of artificial nutrition and hydration) in the presence or absence of pain in non-communicative patients. Here, we aimed to better clarify this issue by re-analyzing previously published data on pain perception (Prog Brain Res 2009 177, 329–38) and end-of-life decisions (J Neurol 2010 258, 1058–65) in patients with disorders of consciousness. In a sample of 2259 European healthcare professionals we found that, for VS/UWS more respondents agreed with treatment withdrawal when they considered that VS/UWS patients did not feel pain (77%) as compared to those who thought VS/UWS did feel pain (59%). This interaction was influenced by religiosity and professional background. For MCS, end-of-life attitudes were not influenced by opinions on pain perception. Within a contemporary ethical context we discuss (1) the evolving scientific understandings of pain perception and their relationship to existing clinical and ethical guidelines; (2) the discrepancies of attitudes within (and between) healthcare providers and their consequences for treatment approaches, and (3) the implicit but complex relationship between pain perception and attitudes toward life-sustaining treatments. [less ▲]

Detailed reference viewed: 222 (14 ULg)
Full Text
Peer Reviewed
See detailComa and related disorders
Charland-Verville, Vanessa ULg; Habbal, Dina; Laureys, Steven ULg et al

in Swiss Archives of Neurology and Psychiatry (2012), 163(8), 265-272

Disorders of consciousness represent a major challenge in clinical practice. The last decade of neuroscience research brought new insights about brain function and neural correlates of these pathological ... [more ▼]

Disorders of consciousness represent a major challenge in clinical practice. The last decade of neuroscience research brought new insights about brain function and neural correlates of these pathological states of consciousness. Although behavioural evaluation still remains the gold standard, conscious behaviours are too often missed, leading to unwanted grey zones between conscious and unconscious patients. In order to increase the chances of detecting the signs of consciousness, scientists now focus on the development and validation of neuroimaging and electrophysiological paradigms in noncommunicative patients. Recent insights in this field also raise new questions of medical ethics. Indeed, for conscious patients, legal questions will occur about treatment plans, rehabilitation and communication strategies while for the unconscious patients, end-of-life decisions will take place after the patients’ condition is stated as “permanent” or “irreversible”. [less ▲]

Detailed reference viewed: 32 (8 ULg)
Full Text
Peer Reviewed
See detailElectrophysiological investigations of brain function in coma, vegetative and minimally conscious patients.
Lehembre, Remy ULg; Gosseries, Olivia ULg; Lugo, Zulay et al

in Archives Italiennes de Biologie (2012), 150(2-3), 122-39

Electroencephalographic activity in the context of disorders of consciousness is a swiss knife like tool that can evaluate different aspects of cognitive residual function, detect consciousness and ... [more ▼]

Electroencephalographic activity in the context of disorders of consciousness is a swiss knife like tool that can evaluate different aspects of cognitive residual function, detect consciousness and provide a mean to communicate with the outside world without using muscular channels. Standard recordings in the neurological department offer a first global view of the electrogenesis of a patient and can spot abnormal epileptiform activity and therefore guide treatment. Although visual patterns have a prognosis value, they are not sufficient to provide a diagnosis between vegetative state/unresponsive wakefulness syndrome (VS/UWS) and minimally conscious state (MCS) patients. Quantitative electroencephalography (qEEG) processes the data and retrieves features, not visible on the raw traces, which can then be classified. Current results using qEEG show that MCS can be differentiated from VS/UWS patients at the group level. Event Related Potentials (ERP) are triggered by varying stimuli and reflect the time course of information processing related to the stimuli from low-level peripheral receptive structures to high-order associative cortices. It is hence possible to assess auditory, visual, or emotive pathways. Different stimuli elicit positive or negative components with different time signatures. The presence of these components when observed in passive paradigms is usually a sign of good prognosis but it cannot differentiate VS/UWS and MCS patients. Recently, researchers have developed active paradigms showing that the amplitude of the component is modulated when the subject's attention is focused on a task during stimulus presentation. Hence significant differences between ERPs of a patient in a passive compared to an active paradigm can be a proof of consciousness. An EEG-based brain-computer interface (BCI) can then be tested to provide the patient with a communication tool. BCIs have considerably improved the past two decades. However they are not easily adaptable to comatose patients as they can have visual or auditory impairments or different lesions affecting their EEG signal. Future progress will require large databases of resting state-EEG and ERPs experiment of patients of different etiologies. This will allow the identification of specific patterns related to the diagnostic of consciousness. Standardized procedures in the use of BCIs will also be needed to find the most suited technique for each individual patient. [less ▲]

Detailed reference viewed: 103 (3 ULg)
Full Text
Peer Reviewed
See detailMetabolic activity in external and internal awareness networks in severely brain-damaged patients.
Thibaut, Aurore ULg; Bruno, Marie-Aurélie ULg; Chatelle, Camille ULg et al

in Journal of Rehabilitation Medicine (2012), 44(6), 487-94

OBJECTIVE: An extrinsic cerebral network (encompassing lateral frontoparietal cortices) related to external/sensory awareness and an intrinsic midline network related to internal/self-awareness have been ... [more ▼]

OBJECTIVE: An extrinsic cerebral network (encompassing lateral frontoparietal cortices) related to external/sensory awareness and an intrinsic midline network related to internal/self-awareness have been identified recently. This study measured brain metabolism in both networks in patients with severe brain damage. DESIGN: Prospective [18F]-fluorodeoxyglucose-positron emission tomography and Coma Recovery Scale-Revised assessments in a university hospital setting. SUBJECTS: Healthy volunteers and patients in vegetative state/unresponsive wakefulness syndrome (VS/UWS), minimally conscious state (MCS), emergence from MCS (EMCS), and locked-in syndrome (LIS). RESULTS: A total of 70 patients were included in the study: 24 VS/UWS, 28 MCS, 10 EMCS, 8 LIS and 39 age-matched controls. VS/UWS showed metabolic dysfunction in extrinsic and intrinsic networks and thalami. MCS showed dysfunction mostly in intrinsic network and thalami. EMCS showed impairment in posterior cingulate/retrosplenial cortices. LIS showed dysfunction only in infratentorial regions. Coma Recovery Scale-Revised total scores correlated with metabolic activity in both extrinsic and part of the intrinsic network and thalami. CONCLUSION: Progressive recovery of extrinsic and intrinsic awareness network activity was observed in severely brain-damaged patients, ranging from VS/UWS, MCS, EMCS to LIS. The predominance of intrinsic network impairment in MCS could reflect altered internal/self-awareness in these patients, which is difficult to quantify at the bedside. [less ▲]

Detailed reference viewed: 205 (52 ULg)
Peer Reviewed
See detailThe ethics of managing disorders of consciousness
Demertzi, Athina ULg; Gosseries, Olivia ULg; Bruno, Marie-Aurélie ULg et al

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

Detailed reference viewed: 31 (2 ULg)
Peer Reviewed
See detailPrognosis of patients with altered states of consciousness
Bruno, Marie-Aurélie ULg; Ledoux, Didier; Vanhaudenhuyse, Audrey ULg et al

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

Detailed reference viewed: 97 (2 ULg)
Peer Reviewed
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)

Detailed reference viewed: 32 (4 ULg)
Full Text
Peer Reviewed
See detailFunctional neuroanatomy underlying the clinical subcategorization of minimally conscious state patients.
Bruno, Marie-Aurélie ULg; Majerus, Steve ULg; Boly, Mélanie ULg et al

in Journal of Neurology (2012), 259(6), 1087-98

Patients in a minimally conscious state (MCS) show restricted signs of awareness but are unable to communicate. We assessed cerebral glucose metabolism in MCS patients and tested the hypothesis that this ... [more ▼]

Patients in a minimally conscious state (MCS) show restricted signs of awareness but are unable to communicate. We assessed cerebral glucose metabolism in MCS patients and tested the hypothesis that this entity can be subcategorized into MCS- (i.e., patients only showing nonreflex behavior such as visual pursuit, localization of noxious stimulation and/or contingent behavior) and MCS+ (i.e., patients showing command following).Patterns of cerebral glucose metabolism were studied using [(18)F]-fluorodeoxyglucose-PET in 39 healthy volunteers (aged 46 +/- 18 years) and 27 MCS patients of whom 13 were MCS- (aged 49 +/- 19 years; 4 traumatic; 21 +/- 23 months post injury) and 14 MCS+ (aged 43 +/- 19 years; 5 traumatic; 19 +/- 26 months post injury). Results were thresholded for significance at false discovery rate corrected p < 0.05.We observed a metabolic impairment in a bilateral subcortical (thalamus and caudate) and cortical (fronto-temporo-parietal) network in nontraumatic and traumatic MCS patients. Compared to MCS-, patients in MCS+ showed higher cerebral metabolism in left-sided cortical areas encompassing the language network, premotor, presupplementary motor, and sensorimotor cortices. A functional connectivity study showed that Broca's region was disconnected from the rest of the language network, mesiofrontal and cerebellar areas in MCS- as compared to MCS+ patients.The proposed subcategorization of MCS based on the presence or absence of command following showed a different functional neuroanatomy. MCS- is characterized by preserved right hemispheric cortical metabolism interpreted as evidence of residual sensory consciousness. MCS+ patients showed preserved metabolism and functional connectivity in language networks arguably reflecting some additional higher order or extended consciousness albeit devoid of clinical verbal or nonverbal expression. [less ▲]

Detailed reference viewed: 201 (10 ULg)
Full Text
Peer Reviewed
See detailRecovery of cortical effective connectivity and recovery of consciousness in vegetative patients.
Rosanova, Mario; Gosseries, Olivia ULg; Casarotto, Silvia et al

in Brain : A Journal of Neurology (2012), 135(Pt 4), 1308-20

Patients surviving severe brain injury may regain consciousness without recovering their ability to understand, move and communicate. Recently, electrophysiological and neuroimaging approaches, employing ... [more ▼]

Patients surviving severe brain injury may regain consciousness without recovering their ability to understand, move and communicate. Recently, electrophysiological and neuroimaging approaches, employing simple sensory stimulations or verbal commands, have proven useful in detecting higher order processing and, in some cases, in establishing some degree of communication in brain-injured subjects with severe impairment of motor function. To complement these approaches, it would be useful to develop methods to detect recovery of consciousness in ways that do not depend on the integrity of sensory pathways or on the subject's ability to comprehend or carry out instructions. As suggested by theoretical and experimental work, a key requirement for consciousness is that multiple, specialized cortical areas can engage in rapid causal interactions (effective connectivity). Here, we employ transcranial magnetic stimulation together with high-density electroencephalography to evaluate effective connectivity at the bedside of severely brain injured, non-communicating subjects. In patients in a vegetative state, who were open-eyed, behaviourally awake but unresponsive, transcranial magnetic stimulation triggered a simple, local response indicating a breakdown of effective connectivity, similar to the one previously observed in unconscious sleeping or anaesthetized subjects. In contrast, in minimally conscious patients, who showed fluctuating signs of non-reflexive behaviour, transcranial magnetic stimulation invariably triggered complex activations that sequentially involved distant cortical areas ipsi- and contralateral to the site of stimulation, similar to activations we recorded in locked-in, conscious patients. Longitudinal measurements performed in patients who gradually recovered consciousness revealed that this clear-cut change in effective connectivity could occur at an early stage, before reliable communication was established with the subject and before the spontaneous electroencephalogram showed significant modifications. Measurements of effective connectivity by means of transcranial magnetic stimulation combined with electroencephalography can be performed at the bedside while by-passing subcortical afferent and efferent pathways, and without requiring active participation of subjects or language comprehension; hence, they offer an effective way to detect and track recovery of consciousness in brain-injured patients who are unable to exchange information with the external environment. [less ▲]

Detailed reference viewed: 58 (2 ULg)
Full Text
Peer Reviewed
See detailBrain connectivity in disorders of consciousness.
Boly, Mélanie ULg; Massimini, Marcello; Garrido, Marta Isabel et al

in Brain connectivity (2012), 2(1), 1-10

The last 10 years witnessed a considerable increase in our knowledge of brain function in survivors to severe brain injuries with disorders of consciousness (DOC). At the same time, a growing interest ... [more ▼]

The last 10 years witnessed a considerable increase in our knowledge of brain function in survivors to severe brain injuries with disorders of consciousness (DOC). At the same time, a growing interest developed for the use of functional neuroimaging as a new diagnostic tool in these patients. In this context, particular attention has been devoted to connectivity studies-as these, more than measures of brain metabolism, may be more appropriate to capture the dynamics of large populations of neurons. Here, we will review the pros and cons of various connectivity methods as potential diagnostic tools in brain-damaged patients with DOC. We will also discuss the relevance of the study of the level versus the contents of consciousness in this context. [less ▲]

Detailed reference viewed: 45 (1 ULg)
Full Text
Peer Reviewed
See detailBurnout in healthcare workers managing chronic patients with disorders of consciousness.
Gosseries, Olivia ULg; Demertzi, Athina ULg; Ledoux, Didier et al

in Brain Injury (2012)

Objectives: The aim of this study was to assess the presence of burnout among professional caregivers managing patients with severe brain injury recovering from coma and working in neurorehabilitation ... [more ▼]

Objectives: The aim of this study was to assess the presence of burnout among professional caregivers managing patients with severe brain injury recovering from coma and working in neurorehabilitation centres or nursing homes. Methods: The Maslach Burnout Inventory was sent to 40 centres involved in the Belgian federal network for the care of vegetative and minimally conscious patients. The following demographic data were also collected: age, gender, profession, expertise in the field, amount of time spent with patients and working place. Results: Out of 1068 questionnaires sent, 568 were collected (53% response rate). Forty-five were excluded due to missing data. From the 523 healthcare workers, 18% (n = 93) presented a burnout, 33% (n = 171) showed emotional exhaustion and 36% (n = 186) had a depersonalization. Profession (i.e. nurse/nursing assistants), working place (i.e. nursing home) and the amount of time spent with patients were associated with burnout. The logistic regression showed that profession was nevertheless the strongest variable linked to burnout. Conclusions: According to this study, a significant percentage of professional caregivers and particularly nurses taking care of patients in a vegetative state and in a minimally conscious state suffered from burnout. Prevention of burnout symptoms among caregivers is crucial and is expected to promote more efficient medical care of these challenging patients. [less ▲]

Detailed reference viewed: 36 (4 ULg)
Full Text
See detailFeasibility of oral feeding in patients with disorders of consciousness
Maudoux, Audrey ULg; BREUSKIN, Ingrid ULg; Gosseries, Olivia ULg et al

in Schnakers, Caroline; Laureys, Steven (Eds.) Coma and Disorders of Consciousness (2012)

Detailed reference viewed: 32 (7 ULg)
Peer Reviewed
See detailDésordres de la conscience : aspects éthiques.
Demertzi, Athina ULg; Gosseries, Olivia ULg; Bruno, Marie-Aurélie ULg et al

in Schnakers, Caroline; LAUREYS, Steven (Eds.) Comas et états de conscience altérée (2011)

L’apparition de la ventilation mécanique dans les années cinquante et le développement des soins intensifs dans les années soixante ont permis à de nombreux patients de survivre à de graves lésions ... [more ▼]

L’apparition de la ventilation mécanique dans les années cinquante et le développement des soins intensifs dans les années soixante ont permis à de nombreux patients de survivre à de graves lésions cérébrales. Bien que ces avancées technologiques soient étonnantes, de nombreux patients vont alors se retrouver dans des états cliniques critiques peu rencontrés auparavant (1). L’impact éthique de ces états d’inconscience se reflète lors de la rédaction des premiers comités de bioéthique et lors de l’apparition du concept d’acharnement thérapeutique. En 1968, le comité spécial de l’école médicale de Harvard a publié un article essentiel redéfinissant la mort comme étant un coma irréversible et une perte permanente de toutes les fonctions cérébrales (2). Le comité, composé de dix médecins, d’un théologien, d’un avocat et d’un historien des sciences, a débattu des questions médicales, juridiques et sociétales quant à la prise en charge des patients en mort cérébrale. Nous donnerons ici un bref aperçu des principales questions éthiques liées à la notion de conscience et à la prise en charge médicale des patients atteints de troubles de la conscience (TDC) tels que le coma, l’état végétatif et l’état de conscience minimale. Nous mettrons également l’accent sur le problème de la gestion de la douleur et des prises de décision en fin de vie. [less ▲]

Detailed reference viewed: 80 (17 ULg)
Full Text
Peer Reviewed
See detailHypnotic modulation of resting state fMRI default mode and extrinsic network connectivity
Demertzi, Athina ULg; Soddu, Andrea ULg; FAYMONVILLE, Marie-Elisabeth ULg et al

in Progress in Brain Research (2011), 193

Resting state fMRI (functional magnetic resonance imaging) acquisitions are characterized by low-frequency spontaneous activity in a default mode network (encompassing medial brain areas and linked to ... [more ▼]

Resting state fMRI (functional magnetic resonance imaging) acquisitions are characterized by low-frequency spontaneous activity in a default mode network (encompassing medial brain areas and linked to self-related processes) and an anticorrelated “extrinsic” system (encompassing lateral frontoparietal areas and modulated via external sensory stimulation). In order to better determine the functional contribution of these networks to conscious awareness, we here sought to transiently modulate their relationship by means of hypnosis. We used independent component analysis (ICA) on resting state fMRI acquisitions during normal wakefulness, under hypnotic state, and during a control condition of autobiographical mental imagery. As compared to mental imagery, hypnosis-induced modulation of resting state fMRI networks resulted in a reduced “extrinsic” lateral frontoparietal cortical connectivity, possibly reflecting a decreased sensory awareness. The default mode network showed an increased connectivity in bilateral angular and middle frontal gyri, whereas its posterior midline and parahippocampal structures decreased their connectivity during hypnosis, supposedly related to an altered “self” awareness and posthypnotic amnesia. In our view, fMRI resting state studies of physiological (e.g., sleep or hypnosis), pharmacological (e.g., sedation or anesthesia), and pathological modulation (e.g., coma or related states) of “intrinsic” default mode and anticorrelated “extrinsic” sensory networks, and their interaction with other cerebral networks, will further improve our understanding of the neural correlates of subjective awareness. [less ▲]

Detailed reference viewed: 110 (22 ULg)