Steven Laureys

..Such studies are disentangling the neural correlates of the vegetative state from the minimally conscious state, and have major clinical consequences in addition to empirical importance for the understanding of consciousness...

..Therefore, better understanding of cerebral noxious processing in these patients is of clinical, therapeutic, and ethical relevance...

..These results emphasize the importance of recurrent corticocortical communication in the maintenance of consciousness and suggest a direct effect of propofol on cortical dynamics...

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..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...

..e., represents "automatic" subcortical processing) or is a sufficient sign of consciousness and higher order cortical processing...

..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...

..This result emphasizes the importance of top-down projections in recurrent processing that involve high-order associative cortices for conscious perception...

..Future studies are needed before using this tool in routine clinical practice, and these should seek to improve automated EEG quantification paradigms in order to reduce the remaining false negative and false positive findings...

..Classically, communication remains possible by means of spared vertical eye movements and/or blinking. To allow assessing cognitive functions in LIS patients, we propose here a neuropsychological testing based on eye-coded communication...

..However, in the absence of a generally accepted neural correlate of consciousness as measured by functional neuroimaging, clinical assessment remains the gold standard for the evaluation and management of severely brain damaged patients...

..Moreover, the involvement of a parietal area in the dual task is in keeping with the hypothesis that a parieto-frontal network sustains executive functioning...

..The results of this neuroimaging study are in agreement with cognitive studies demonstrating that executive functioning is characterized by both unity and diversity of processes...

..Consequently, this rCBF distribution might preferentially reflect a particular modulation of the cellular processes involved in the generation of cortical delta waves during NREM sleep...

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..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...

..Resting-state functional magnetic resonance imaging allows investigating whole-brain connectivity changes during pharmacological modulation of the level of consciousness...

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..We compared the FOUR and GLS/GCS in intensive care unit patients who were admitted in a comatose state...

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..e., VS or MCS). The NCS constitutes a sensitive clinical tool for assessing nociception in severely brain-injured patients. This scale constitutes the first step to a better management of patients recovering from coma...

..We place these findings in light of recent findings on the architecture of spontaneous BOLD fluctuations in the awake human brain, and discuss the possible origins of the observed baseline brain activity fluctuations...

..In coma-survivors, cognitive potentials are more frequently obtained when using stimuli that are more ecologic or have an emotional content (such as the patient's own name) than when using classical sine tones...

..The minimally conscious state (MCS) is a recently defined clinical condition; it differs from the persistent vegetative state (PVS) by the presence of inconsistent, but clearly discernible, behavioral evidence of consciousness...

..They stress the important role played by parietal and frontal areas in the generation of consciousness...

..Future prospective studies in a larger patient population are needed in order to evaluate the prognostic value of the presented methodology...

..We here aimed to identify the DMN in the challenging patient population of disorders of consciousness encountered following coma...

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..These findings raise important ethical considerations in terms of quality of life and end-of-life decisions in such challenging cases...

..In addition to novel behavioural 'consciousness-scales', the role of para-clinical markers of consciousness, such as event related potentials and functional neuroimaging is reviewed...

..Therefore, RVM classification of cerebral metabolic images obtained in coma survivors could become a useful tool for the automated PET-based diagnosis of altered states of consciousness...

..The combined use of behavioral and neuroimaging assessment techniques appears to be particularly promising for disentangling impaired consciousness and aphasia...

..Our goal in this observational study was to map brain regions whose activity is modified by clonidine infusion so as to better understand its loci of action, especially in relation to sedation...

..Results indicate that the human brain has already extensively processed recent memories during the first hours of post-training wakefulness, even when simultaneously coping with unrelated cognitive demands...

..Such modifications in brain connectivity, possibly driven by sleep ultraslow oscillations, could hinder the brain's ability to integrate information and account for decreased consciousness during NREM sleep...

..We here review these advances in measurement and the scientific and broader implications of this rapidly progressing field of research...

..Pain monitoring in these patients is hence of medical and ethical importance. In this article, we will focus on the possible use of behavioral scales for the assessment and detection of pain in noncommunicative patients...

..Based on these results we discuss what we currently do and do not know about the functional significance of the neural network involved in "automatic" and "conscious" self-referential processing...

..It is suggested that the VMPFC is crucial for representing knowledge pertaining to the self and that this is an important function of the resting state...

..The clinical application of these functional neuroimaging techniques awaits validation from ongoing multi-centric cohort studies in these challenging patients with chronic disorders of consciousness...

..At the present time the interactions of sleep and consciousness in brain-injured patients are a little studied subject but, the authors suggest, a potentially very interesting field of research...

..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...

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..In this study, we compared consensus-based diagnoses of VS and MCS to those based on a well-established standardized neurobehavioral rating scale, the JFK Coma Recovery Scale-Revised (CRS-R)...

..s proposal. Based on the above considerations, we suggest and discuss a revised model for upper limb apraxia that might best account for both brain imaging findings and neuropsychological dissociations reported in the apraxia literature...

..This study measured brain metabolism in both networks in patients with severe brain damage...

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..In our opinion, there is an urgent need for a renewed ethical and medicolegal framework for our care of locked-in patients...

..Here we review current possibilities and limitations of clinical and para-clinical assessment of chronic disorders of consciousness...

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..This case shows that old dogmas need to be oppugned, as recovery with meaningful reduction in disability continued in this case for nearly 2 decades after extremely severe traumatic brain injury...

..We discuss the problems of evidence-based neurorehabilitation in disorders of consciousness, and recent functional neuroimaging data obtained in the vegetative state and minimally conscious state...

..g., the temporoparietal junction). We hypothesize that these patients are impaired in the ability to see themselves with a third-person perspective (i.e., being able to see themselves as other people see them)...

..However, use of this technique in severe brain damage remains methodologically ill-defined and must be further validated prior to clinical application in these challenging patients...

..The latter is known to occur in drug dependence and could predispose subgroups of migraineurs to recurrent analgesic overuse...

..We argue that the emotional value or the high familiarity of one's own face may explain its attention-grabbing property...

..This syndrome has been coined vegetative state. We here present a new name for this challenging neurological condition: unresponsive wakefulness syndrome (abbreviated UWS)...

..Our data provide the first experimental evidence for a link between behavioral performance and cerebral reactivation during REM sleep...

..This suggests a functional reorganization of central cardiovascular regulation during REMS...

..However its mode of action remains elusive. Since the long delay to meaningful effect suggests that ONS induces slow neuromodulation, we have searched for changes in central pain-control areas using metabolic neuroimaging...

..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...

..These findings have highlighted the potential for the development of simple brain-computer interfaces (BCI) as a diagnosis in behaviourally unresponsive patients...

..In this commentary, we illustrate the relationship between oriented eye movements, consciousness, and emotion by using the case of severely brain-injured patients recovering from coma (i.e., vegetative and minimally conscious patients)...

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..These data suggest that impaired verbal STM at late outcome of LKS might indeed be related to a persistent decrease of activity in those posterior superior temporal gyri that were involved in the epileptic focus during the active phase...

..However, this activation is limited to primary cortices and dissociated from higher-order associative cortices, thought to be necessary for conscious perception...

..Neuroimaging techniques remain important tools for clinical research that will extend our understanding of the underlying mechanisms of these disorders...

..It represents an interdisciplinary approach to the challenges posed by the emerging use of neuroimaging technologies to describe and characterize disorders of consciousness...

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..They also supply further evidence for a partial dissociation between the neural substrates supporting conscious and nonconscious components of performance during recollection of a learned sequence...

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..Activity in the hypothalamus decreased in proportion to previous illumination. These findings have important implications for understanding the effects of light on human behavior...

..These results suggest that the medial prefrontal cortex plays the most prominent role in self-processing...

..Such functions can be viewed as properties of the subject, rather than the object, of experience - the 'observing self' that appears to be needed to maintain the conscious state...

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..This suggests a significant role for the ACC/MPFC in the explicit processing of sequential material...

..In this issue of Neuron, provide behavioral evidence that most of the improvement of a motor skill depends on nocturnal sleep...

..These preliminary findings are encouraging in the search for electrophysiological correlates of consciousness in severe acute brain damage...

..To describe the theoretic framework, design, and potential clinical applications of functional neuroimaging protocols in patients with disorders of consciousness...

..When asked to imagine playing tennis or moving around her home, the patient activated predicted cortical areas in a manner indistinguishable from that of healthy volunteers...

..A major challenge in the management of severely brain-injured patients with altered states of consciousness is to estimate their residual perception of the environment...

..These findings show that not only pharmacological but also psychological strategies for pain control can modulate the cerebral network involved in noxious perception...

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