References of "Laureys, Steven"
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See detailOrgan Procurement After Euthanasia: Belgian Experience
Ysebaert, dirk; Van Beeumen, G.; De Greef, K. et al

in Transplantation Proceedings (2009), 41

Euthanasia was legalized in Belgium in 2002 for adults under strict conditions. The patient must be in a medically futile condition and of constant and unbearable physical or mental suffering that cannot ... [more ▼]

Euthanasia was legalized in Belgium in 2002 for adults under strict conditions. The patient must be in a medically futile condition and of constant and unbearable physical or mental suffering that cannot be alleviated, resulting from a serious and incurable disorder caused by illness or accident. Between 2005 and 2007, 4 patients (3 in Antwerp and 1 in Liège) expressed their will for organ donation after their request for euthanasia was granted. Patients were aged 43 to 50 years and had a debilitating neurologic disease, either after severe cerebrovascular accident or primary progressive multiple sclerosis. Ethical boards requested complete written scenario with informed consent of donor and relatives, clear separation between euthanasia and organ procurement procedure, and all procedures to be performed by senior staff members and nursing staff on a voluntary basis. The euthanasia procedure was performed by three independent physicians in the operating room. After clinical diagnosis of cardiac death, organ procurement was performed by femoral vessel cannulation or quick laparotomy. In 2 patients, the liver, both kidneys, and pancreatic islets (one case) were procured and transplanted; in the other 2 patients, there was additional lung procurement and transplantation. Transplant centers were informed of the nature of the case and the elements of organ procurement. There was primary function of all organs. The involved physicians and transplant teams had the well-discussed opinion that this strong request for organ donation after euthanasia could not be waived. A clear separation between the euthanasia request, the euthanasia procedure, and the organ procurement procedure is necessary. [less ▲]

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See detailReaching across the abyss: recent advances in functional magnetic resonance imaging and their potential relevance to disorders of consciousness
Soddu, Andrea ULg; Boly, Mélanie ULg; Nir, Yval et al

in Progress in Brain Research (2009), 177

Disorders of consciousness (DOC) raise profound scientific, clinical, ethical, and philosophical issues. Growing knowledge on fundamental principles of brain organization in healthy individuals offers new ... [more ▼]

Disorders of consciousness (DOC) raise profound scientific, clinical, ethical, and philosophical issues. Growing knowledge on fundamental principles of brain organization in healthy individuals offers new opportunities for a better understanding of residual brain function in DOCs. We here discuss new perspectives derived from a recently proposed scheme of brain organization underlying consciousness in healthy individuals. In this scheme, thalamo-cortical networks can be divided into two, often antagonistic, global systems: (i) a system of externally oriented, sensory-motor networks (the "extrinsic" system); and (ii) a system of inward-oriented networks (the "intrinsic" or default system). According to this framework, four distinct mental states would be possible that could be relevant for understanding DOCs. In normal healthy volunteers and locked-in syndrome patients, a state of high functionality of both the extrinsic and intrinsic or default systems is expected--associated with full awareness of environment and self. In this case, mental imagery tasks combined with fMRI can be used to detect covert awareness in patients that are unable to communicate. <br /> <br />According to the framework, two complementary states of system imbalance are also possible, in which one system is in a hyperfunctional state, while the other is hypoactive. Extrinsic system hyperfunction is expected to lead to a state of total sensory-motor "absorption" or "lost self." In contrast, intrinsic or default system hyperfunction is expected to lead to a state of complete detachment from the external world. A state where both extrinsic and intrinsic systems are hypofunctional is predicted to lead to markedly impaired consciousness as seen in DOCs. Finally, we review the potential use of ultra-slow fluctuations in BOLD signal as a tool for assessing the functional integrity of extrinsic and intrinsic systems during "resting state" fMRI acquisitions. In particular, we discuss the potential provided by assessment of these slow spontaneous BOLD fluctuations as a novel tool in assessing the cognitive state and chances of recovery from brain pathologies underlying DOCs. [less ▲]

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See detailDualism persists in the science of mind.
Demertzi, Athina ULg; Liew, Charlene; Ledoux, Didier ULg et al

in Annals of the New York Academy of Sciences (2009), 1157

The relationship between mind and brain has philosophical, scientific, and practical implications. Two separate but related surveys from the University of Edinburgh (University students, n= 250) and the ... [more ▼]

The relationship between mind and brain has philosophical, scientific, and practical implications. Two separate but related surveys from the University of Edinburgh (University students, n= 250) and the University of Liege (health-care workers, lay public, n= 1858) were performed to probe attitudes toward the mind-brain relationship and the variables that account for differences in views. Four statements were included, each relating to an aspect of the mind-brain relationship. The Edinburgh survey revealed a predominance of dualistic attitudes emphasizing the separateness of mind and brain. In the Liege survey, younger participants, women, and those with religious beliefs were more likely to agree that the mind and brain are separate, that some spiritual part of us survives death, that each of us has a soul that is separate from the body, and to deny the physicality of mind. Religious belief was found to be the best predictor for dualistic attitudes. Although the majority of health-care workers denied the distinction between consciousness and the soma, more than one-third of medical and paramedical professionals regarded mind and brain as separate entities. The findings of the study are in line with previous studies in developmental psychology and with surveys of scientists' attitudes toward the relationship between mind and brain. We suggest that the results are relevant to clinical practice, to the formulation of scientific questions about the nature of consciousness, and to the reception of scientific theories of consciousness by the general public. [less ▲]

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See detailAnother kind of 'BOLD Response': answering multiple-choice questions via online decoded single-trial brain signals.
Sorger, Bettina; Dahmen, Brigitte; Reithler, Joel et al

in Progress in Brain Research (2009), 177

The term 'locked-in'syndrome (LIS) describes a medical condition in which persons concerned are severely paralyzed and at the same time fully conscious and awake. The resulting anarthria makes it ... [more ▼]

The term 'locked-in'syndrome (LIS) describes a medical condition in which persons concerned are severely paralyzed and at the same time fully conscious and awake. The resulting anarthria makes it impossible for these patients to naturally communicate, which results in diagnostic as well as serious practical and ethical problems. Therefore, developing alternative, muscle-independent communication means is of prime importance. Such communication means can be realized via brain-computer interfaces (BCIs) circumventing the muscular system by using brain signals associated with preserved cognitive, sensory, and emotional brain functions. Primarily, BCIs based on electrophysiological measures have been developed and applied with remarkable success. Recently, also blood flow-based neuroimaging methods, such as functional magnetic resonance imaging (fMRI) and functional near-infrared spectroscopy (fNIRS), have been explored in this context. After reviewing recent literature on the development of especially hemodynamically based BCIs, we introduce a highly reliable and easy-to-apply communication procedure that enables untrained participants to motor-independently and relatively effortlessly answer multiple-choice questions based on intentionally generated single-trial fMRI signals that can be decoded online. Our technique takes advantage of the participants' capability to voluntarily influence certain spatio-temporal aspects of the blood oxygenation level-dependent (BOLD) signal: source location (by using different mental tasks), signal onset and offset. We show that healthy participants are capable of hemodynamically encoding at least four distinct information units on a single-trial level without extensive pretraining and with little effort. Moreover, real-time data analysis based on simple multi-filter correlations allows for automated answer decoding with a high accuracy (94.9%) demonstrating the robustness of the presented method. Following our 'proof of concept', the next step will involve clinical trials with LIS patients, undertaken in close collaboration with their relatives and caretakers in order to elaborate individually tailored communication protocols. As our procedure can be easily transferred to MRI-equipped clinical sites, it may constitute a simple and effective possibility for online detection of residual consciousness and for LIS patients to communicate basic thoughts and needs in case no other alternative communication means are available (yet)--especially in the acute phase of the LIS. Future research may focus on further increasing the efficiency and accuracy of fMRI-based BCIs by implementing sophisticated data analysis methods (e.g., multivariate and independent component analysis) and neurofeedback training techniques. Finally, the presented BCI approach could be transferred to portable fNIRS systems as only this would enable hemodynamically based communication in daily life situations. [less ▲]

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See detailEthical implications : pain, coma and related disorders
Schnakers, Caroline ULg; Faymonville, Marie ULg; Laureys, Steven ULg

in Banks, William P. (Ed.) Encyclopedia of Consciousness (2009)

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See detailMagnetic resonance spectroscopy and diffusion tensor imaging in coma survivors: promises and pitfalls.
TSHIBANDA, Luaba ULg; Vanhaudenhuyse, Audrey ULg; Galanaud, Damien et al

in Progress in Brain Research (2009), 177

The status of comatose patient is currently established on the basis of the patient-exhibited behaviors. Clinical assessment is subjective and, in 40% of patients, fails to distinguish vegetative state ... [more ▼]

The status of comatose patient is currently established on the basis of the patient-exhibited behaviors. Clinical assessment is subjective and, in 40% of patients, fails to distinguish vegetative state (VS) from minimally conscious states (MCS). The technologic advances of magnetic resonance imaging (MRI) have dramatically improved our understanding of these altered states of consciousness. The role of neuroimaging in coma survivors has increased beyond the simple evaluation of morphological abnormalities. The development of 1H-MR spectroscopy (MRS) and diffusion tensor imaging (DTI) provide opportunity to evaluate processes that cannot be approached by current morphologic MRI sequences. They offer potentially unique insights into the histopathology of VS and MCS. The MRS is a powerful noninvasive imaging technique that enables the in vivo quantification of certain chemical compound or metabolites as N-acetylaspartate (NAA), Choline (Cho), and Creatine (Cr). These biomarkers explore neuronal integrity (NAA), cell membrane turnover (Cho), and cell energetic function (Cr). DTI is an effective and proved quantitative method for evaluating tissue integrity at microscopic level. It provides information about the microstructure and the architecture of tissues, especially the white matter. Various physical parameters can be extracted from this sequence: the fractional anisotropy (FA), a marker of white matter integrity; mean diffusivity (MD); and the apparent diffusion coefficient (ADC) which can differentiate cytotoxic and vasogenic edema. The most prominent findings with MRS and DTI performed in traumatic brain-injured (TBI) patients in subacute phase are the reduction of the NAA/Cr ratio in posterior pons and the decrease of mean infratentorial and supratentorial FA except in posterior pons that enables to predict unfavorable outcome at 1 year from TBI with up to 86% sensitivity and 97% specificity. This review will focus on the interest of comatose patients MRI multimodal assessment with MRS and DTI. It will emphasize the advantages and pitfalls of these techniques in particular in predicting the coma survivors' outcome. [less ▲]

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See detailNeurophysiological correlates of hypnotic analgesia
Vanhaudenhuyse, Audrey ULg; Boly, Mélanie ULg; Laureys, Steven ULg et al

in Contemporary Hypnosis (2009), 26(1), 1523

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See detailNeurophysiological correlates of hypnotic analgesia
Vanhaudenhuyse, Audrey ULg; Boly, Mélanie ULg; Laureys, Steven ULg et al

in Contemporary Hypnosis (2009), 26(1), 15-23

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See detailPain and non-pain processing during hypnosis: a thulium-YAG event-related fMRI study.
Vanhaudenhuyse, Audrey ULg; Boly, Mélanie ULg; Balteau, Evelyne ULg et al

in NeuroImage (2009), 47(3), 1047-54

The neural mechanisms underlying the antinociceptive effects of hypnosis still remain unclear. Using a parametric single-trial thulium-YAG laser fMRI paradigm, we assessed changes in brain activation and ... [more ▼]

The neural mechanisms underlying the antinociceptive effects of hypnosis still remain unclear. Using a parametric single-trial thulium-YAG laser fMRI paradigm, we assessed changes in brain activation and connectivity related to the hypnotic state as compared to normal wakefulness in 13 healthy volunteers. Behaviorally, a difference in subjective ratings was found between normal wakefulness and hypnotic state for both non-painful and painful intensity-matched stimuli applied to the left hand. In normal wakefulness, non-painful range stimuli activated brainstem, contralateral primary somatosensory (S1) and bilateral insular cortices. Painful stimuli activated additional areas encompassing thalamus, bilateral striatum, anterior cingulate (ACC), premotor and dorsolateral prefrontal cortices. In hypnosis, intensity-matched stimuli in both the non-painful and painful range failed to elicit any cerebral activation. The interaction analysis identified that contralateral thalamus, bilateral striatum and ACC activated more in normal wakefulness compared to hypnosis during painful versus non-painful stimulation. Finally, we demonstrated hypnosis-related increases in functional connectivity between S1 and distant anterior insular and prefrontal cortices, possibly reflecting top-down modulation. [less ▲]

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See detailDetecting consciousness in a total Locked-in syndrome: an active event related paradigm
Schnakers, Caroline ULg; Perrin, Fabien; Schabus, Manuel et al

in Neurocase : Case Studies in Neuropsychology, Neuropsychiatry & Behavioural Neurology (2009), 25

Total locked-in syndrome is characterized by tetraplegia, anarthria and paralysis of eye motility. In this study, consciousness was detected in a 21-year-old woman who presented a total locked-in syndrome ... [more ▼]

Total locked-in syndrome is characterized by tetraplegia, anarthria and paralysis of eye motility. In this study, consciousness was detected in a 21-year-old woman who presented a total locked-in syndrome after a basilar artery thrombosis (49 days post-injury) using an active event-related paradigm. The patient was presented sequences of names containing the patient's own name and other names. The patient was instructed to count her own name or to count another target name. Similar to 4 age- and gender-matched healthy controls, the P3 response recorded for the voluntarily counted own name was larger than while passively listening. This P3 response was observed 14 days before the first behavioral signs of consciousness. This study shows that our active event-related paradigm allowed to identify voluntary brain activity in a patient who would behaviorally be diagnosed as comatose. [less ▲]

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See detailHypnosis and cingulate-mediated mechanisms of analgesia
FAYMONVILLE, Marie-Elisabeth ULg; Vogt, Brent; Maquet, Pierre ULg et al

in Vogt, Brent (Ed.) Cingulate Neurobiology and Disease (2009)

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See detailNEUROPHYSIOLOGICAL CORRELATES OF HYPNOTIC ANALGESIA
Vanhaudenhuyse, Audrey ULg; Boly, Mélanie ULg; LAUREYS, Steven ULg et al

in Contemporary Hypnosis (2009), 26(1), 15-23

This short review describes recent advances in understanding hypnotic modulation of pain. Our current understanding of pain perception is followed by a critical review of the hypnotic analgesia studies ... [more ▼]

This short review describes recent advances in understanding hypnotic modulation of pain. Our current understanding of pain perception is followed by a critical review of the hypnotic analgesia studies using EEG, evoked potential and functional imaging methodologies. [less ▲]

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See detailConsciousness in the Locked-in Syndrome
Gosseries, Olivia ULg; Bruno, Marie-Aurélie ULg; Vanhaudenhuyse, Audrey ULg et al

in S. Laureys & G. Tononi (Ed.) The Neurology of Consciousness (2009)

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See detailMécanismes de l'anesthésie générale: apport de l'imagerie fonctionnelle
Boveroux, Pierre ULg; Bonhomme, Vincent ULg; Kirsch, Murielle ULg et al

in Revue Médicale de Liège (2009), 64(Synthèse 2009), 36-41

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See detailSleep and Sleep States: PET activation patterns
Dang Vu, Thien Thanh ULg; Desseilles, Martin ULg; Peigneux, Philippe ULg et al

in Squire, Larry (Ed.) Encyclopedia of Neuroscience (2009)

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See detailPET activation patterns
Dang Vu, Thien Thanh ULg; Desseilles, Martin ULg; Peigneux, Philippe ULg et al

in Stickgold, Robert; Walker, Matthew (Eds.) The Neuroscience of Sleep (2009)

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See detailApport de la neuro-imagerie fonctionnelle à l'étude de la douleur
Fontaine, Robert ULg; Vanhaudenhuyse, Audrey ULg; Demertzi, Athina ULg et al

in Revue du Rhumatisme (2009), 76

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See detailMRI in coma survivors
TSHIBANDA, Luaba ULg; Vanhaudenhuyse, Audrey ULg; Bruno, Marie-Aurélie ULg et al

in Revue Médicale de Liège (2009), 64

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See detailNeural substrates of phonological and lexicosemantic representations in Alzheimer's disease.
Peters, Frederic; Majerus, Steve ULg; Collette, Fabienne ULg et al

in Human Brain Mapping (2009), 30(1), 185-99

The language profile of patients suffering from Alzheimer's disease (AD) is characterized not only by lexicosemantic impairments but also by phonological deficits, as shown by an increasing number of ... [more ▼]

The language profile of patients suffering from Alzheimer's disease (AD) is characterized not only by lexicosemantic impairments but also by phonological deficits, as shown by an increasing number of neuropsychological studies. This study explored the functional neural correlates underlying phonological and lexicosemantic processing in AD. Using H(215)O PET functional brain imaging, a group of mild to moderate AD patients and a group of age-matched controls were asked to repeat four types of verbal stimuli: words, wordlike nonwords (WL+), non-wordlike nonwords (WL-) and simple vowels. The comparison between the different conditions allowed us to determine brain activation preferentially associated with lexicosemantic or phonological levels of language representations. When repeating words, AD patients showed decreased activity in the left temporo-parietal and inferior frontal regions relative to controls, consistent with distorted lexicosemantic representations. Brain activity was abnormally increased in the right superior temporal area during word repetition, a region more commonly associated with perceptual-phonological processing. During repetition of WL+ and WL- nonwords, AD patients showed decreased activity in the middle part of the superior temporal gyrus, presumably associated with sublexical phonological information; at the same time, AD patients showed larger activation than controls in the inferior temporal gyrus, typically associated with lexicosemantic levels of representation. Overall, the results suggest that AD patients use altered pathways to process phonological and lexicosemantic information, possibly related to a progressive loss of specialization of phonological and lexicosemantic neural networks. [less ▲]

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See detailFunctional connectivity in the default network during resting state is preserved in a vegetative but not in a brain dead patient.
Boly, Mélanie ULg; Tshibanda, Luaba ULg; Vanhaudenhuyse, Audrey ULg et al

in Human Brain Mapping (2009), 30(8), 2393-400

Recent studies on spontaneous fluctuations in the functional MRI blood oxygen level-dependent (BOLD) signal in awake healthy subjects showed the presence of coherent fluctuations among functionally ... [more ▼]

Recent studies on spontaneous fluctuations in the functional MRI blood oxygen level-dependent (BOLD) signal in awake healthy subjects showed the presence of coherent fluctuations among functionally defined neuroanatomical networks. However, the functional significance of these spontaneous BOLD fluctuations remains poorly understood. By means of 3 T functional MRI, we demonstrate absent cortico-thalamic BOLD functional connectivity (i.e. between posterior cingulate/precuneal cortex and medial thalamus), but preserved cortico-cortical connectivity within the default network in a case of vegetative state (VS) studied 2.5 years following cardio-respiratory arrest, as documented by extensive behavioral and paraclinical assessments. In the VS patient, as in age-matched controls, anticorrelations could also be observed between posterior cingulate/precuneus and a previously identified task-positive cortical network. Both correlations and anticorrelations were significantly reduced in VS as compared to controls. A similar approach in a brain dead patient did not show any such long-distance functional connectivity. We conclude that some slow coherent BOLD fluctuations previously identified in healthy awake human brain can be found in alive but unaware patients, and are thus unlikely to be uniquely due to ongoing modifications of conscious thoughts. Future studies are needed to give a full characterization of default network connectivity in the VS patients population. [less ▲]

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