In:The Constitution of Phenomenal Consciousness: Toward a science and theory
Edited by Steven M. Miller
[Advances in Consciousness Research 92] 2015
► pp. 48–80
The scientific study of coma and related states
Vanessa Charland-Verville | Coma Science Group, Cyclotron Research Centre and Neurology Department, University Hospital of Liège and University of Liège, Liège
Audrey Vanhaudenhuyse | Coma Science Group, Cyclotron Research Centre and Neurology Department, University Hospital of Liège and University of Liège, Liège
Steven Laureys | Coma Science Group, Cyclotron Research Centre and Neurology Department, University Hospital of Liège and University of Liège, Liège
Olivia Gosseries | Coma Science Group, Cyclotron Research Centre and Neurology Department, University Hospital of Liège and University of Liège, Liège
Published online: 17 June 2015
https://doi.org/10.1075/aicr.92.03cha
https://doi.org/10.1075/aicr.92.03cha
The past 15 years have provided an unprecedented collection of discoveries that bear upon our scientific understanding of consciousness. Taken together, recent studies show that awareness is an emergent property of the collective behavior of frontoparietal top-down connectivity. Within this network, external (sensory) awareness depends on lateral prefrontal/parietal cortices while internal (self) awareness correlates with precuneal/mesiofrontal midline activity. An improved assessment of brain function in coma and related states is not only changing nosology and medical care but also offers a better-documented diagnosis and prognosis and helps to further identify the neural correlates of human consciousness. This chapter provides an overview of the scientific study of coma and related states at the macroscopic systems level.
References (164)
Alkire, M.T., Haier, R.J., & Fallon, J.H. (2000). Toward a unified theory of narcosis: Brain imaging evidence for a thalamocortical switch as the neurophysiologic basis of anesthetic-induced unconsciousness. Consciousness and Cognition, 9(3), 370–386.
Alkire, M.T., Hudetz, A.G., & Tononi, G. (2008). Consciousness and anesthesia. Science, 322(5903), 876–880.
Alkire, M.T., Pomfrett, C.J., Haier, R.J., Gianzero, M.V., Chan, C.M., Jacobsen, B.P., & Fallon, J.H. (1999). Functional brain imaging during anesthesia in humans: Effects of halothane on global and regional cerebral glucose metabolism. Anesthesiology, 90(3), 701–709.
Andrews, K. (2004). Medical decision making in the vegetative state: Withdrawal of nutrition and hydration. Neurorehabilitation, 19(4), 299–304.
Baars, B.J. (2002). The conscious access hypothesis: Origins and recent evidence. Trends in Cognitive Sciences, 6(1), 47–52.
. (2005). Global workspace theory of consciousness: Toward a cognitive neuroscience of human experience. Progress in Brain Research, 150, 45–53.
Baars, B.J., Ramsoy, T.Z., & Laureys, S. (2003). Brain, conscious experience and the observing self. Trends in Neurosciences, 26(12), 671–675.
Bassetti, C., Vella, S., Donati, F., Wielepp, P., & Weder, B. (2000). SPECT during sleepwalking. Lancet, 356(9228), 484–485.
Bauer, G., Gerstenbrand, F., & Rumpl, E. (1979). Varieties of the locked-in syndrome. Journal of Neurology, 221(2), 77–91.
Bekinschtein, T., Leiguarda, R., Armony, J., Owen, A., Carpintiero, S., Niklison, J., Sigman, L., Olmos, L., & Manes, F. (2004). Emotion processing in the minimally conscious state. Journal of Neurology, Neurosurgery and Psychiatry, 75(5), 788.
Bernat, J.L. (2002). Questions remaining about the minimally conscious state. Neurology, 58(3), 337–338.
Biswal, B., Yetkin, F.Z., Haughton, V.M., & Hyde, J.S. (1995). Functional connectivity in the motor cortex of resting human brain using echo-planar MRI. Magnetic Resonance in Medicine, 34(4), 537–541.
Boly, M., Coleman, M.R., Davis, M.H., Hampshire, A., Bor, D., Moonen, G., Maquet, P.A., Pickard, J.D., Laureys, S., & Owen, A.M. (2007). When thoughts become action: An fMRI paradigm to study volitional brain activity in non-communicative brain injured patients. Neuroimage, 36(3), 979–992.
Boly, M., Faymonville, M.-E., Peigneux, P., Lambermont, B., Damas, P., Del Fiore, G., Degueldre, C., Franck, G., Luxen, A., Lamy, M., Moonen, G., Maquet, P., & Laureys, S. (2004). Auditory processing in severely brain injured patients: Differences between the minimally conscious state and the persistent vegetative state. Archives of Neurology, 61(2), 233–238.
Boly, M., Faymonville, M.-E., Schnakers, C., Peigneux, P., Lambermont, B., Phillips, C., Lancellotti, P., Luxen, A., Lamy, M., Moonen, G., Maquet, P., & Laureys, S. (2008). Perception of pain in the minimally conscious state with PET activation: An observational study. Lancet Neurology, 7(11), 1013–1020.
Boly, M., Moran, R., Murphy, M., Boveroux, P., Bruno, M.-A., Noirhomme, Q., Ledoux, D., Bonhomme, V., Brichant, J.F., Tononi, G., Laureys, S., & Friston, K. (2012). Connectivity changes underlying spectral EEG changes during propofol-induced loss of consciousness. Journal of Neuroscience, 32(20), 7082–7090.
Boly, M., Phillips, C., Balteau, E., Schnakers, C., Degueldre, C., Moonen, G., Luxen, A., Peigneux, P., Faymonville, M.E., Maquet, P., & Laureys, S. (2008). Consciousness and cerebral baseline activity fluctuations. Human Brain Mapping, 29(7), 868–874.
Boly, M., Sanders, R.D., Mashour, G.A., & Laureys, S. (2013). Consciousness and responsiveness: Lessons from anaesthesia and the vegetative state. Current Opinion in Anesthesiology, 26(4), 444–449.
Boly, M., Tshibanda, L., Vanhaudenhuyse, A., Noirhomme, Q., Schnakers, C., Ledoux, D., Boveroux, P., Garweg, C., Lambermont, B., Phillips, C., Luxen, A., Moonen, G., Bassetti, C., Maquet, P., & Laureys, S. (2009). Functional connectivity in the default network during resting state is preserved in a vegetative but not in a brain dead patient. Human Brain Mapping, 30(8), 2393–2400.
Bonhomme, V., Fiset, P., Meuret, P., Backman, S., Plourde, G., Paus, T., Bushnell, M.C., & Evans, A.C. (2001). Propofol anesthesia and cerebral blood flow changes elicited by vibrotactile stimulation: A positron emission tomography study. Journal of Neurophysiology, 85(3), 1299–1308.
Born, J.D. (1988). The Glasgow-Liege Scale. Prognostic value and evolution of motor response and brain stem reflexes after severe head injury. Acta Neurochirurgica, 91(1–2), 1–11.
Boveroux, P., Bonhomme, V., Boly, M., Vanhaudenhuyse, A., Maquet, P., & Laureys, S. (2008). Brain function in physiologically, pharmacologically, and pathologically altered states of consciousness. International Anesthesiology Clinics, 46(3), 131–146.
Boveroux, P., Vanhaudenhuyse, A., Bruno, M.-A., Noirhomme, Q., Lauwick, S., Luxen, A., Degueldre, C., Plenevaux, A., Schnakers, C., Phillips, C., Brichant, J.F., Bonhomme, V., Maquet, P., Greicius, M.D., Laureys, S., & Boly, M. (2010). Breakdown of within- and between-network resting state functional magnetic resonance imaging connectivity during propofol-induced loss of consciousness. Anesthesiology, 113(5), 1038–1053.
Bruno, M., Bernheim, J.L., Schnakers, C., & Laureys, S. (2008). Locked-in: Don’t judge a book by its cover. Journal of Neurology, Neurosurgery and Psychiatry, 79(1), 2.
Bruno, M.-A., Gosseries, O., Ledoux, D., Hustinx, R., & Laureys, S. (2011). Assessment of consciousness with electrophysiological and neurological imaging techniques. Current Opinion in Critical Care, 17(2), 146–151.
Bruno, M.-A., Gosseries, O., Vanhaudenhuyse, A., Chatelle, C., & Laureys, S. (2010). Etat végétatif et état de conscience minimale: Un devenir pire que la mort. In L. Puybasset (Ed.), Enjeux éthiques en réanimation (pp.119–127). Paris: Springer.
Bruno, M.-A., Ledoux, D., Lambermont, B., Damas, F., Schnakers, C., Vanhaudenhuyse, A., Gosseries, O., & Laureys, S. (2011). Comparison of the Full Outline of UnResponsiveness and Glasgow Liege Scale/Glasgow Coma Scale in an intensive care unit population. Neurocritical Care, 15(3), 447–453.
Bruno, M.-A., Ledoux, D., Vanhaudenhuyse, A., Gosseries, O., Thibaut, A., & Laureys, S. (2012). Prognosis of patients with altered state of consciousness. In C. Schnakers & S. Laureys (Eds.), Coma and disorders of consciousness (pp.11–23). Paris: Springer-Verlag.
Bruno, M.-A., Majerus, S., Boly, M., Vanhaudenhuyse, A., Schnakers, C., Gosseries, O., Boveroux, P., Kirsch, M., Demertzi, A., Bernard, C., Hustinx, R., Moonen, G., & Laureys, S. (2012). Functional neuroanatomy underlying the clinical subcategorization of minimally conscious state patients. Journal of Neurology, 259(6), 1087–1098.
Bruno, M.-A., Schnakers, C., Damas, F., Pellas, F., Lutte, I., Bernheim, J., Majerus, S., Moonen, G., Goldman, S., & Laureys, S. (2009). Locked-in syndrome in children: Report of five cases and review of the literature. Pediatric Neurology, 41(4), 237–246.
Bruno, M.-A., Vanhaudenhuyse, A., Thibaut, A., Moonen, G., & Laureys, S. (2011). From unresponsive wakefulness to minimally conscious PLUS and functional locked-in syndromes: Recent advances in our understanding of disorders of consciousness. Journal of Neurology, 258(7), 1373–1384.
Cairns, H., Oldfield, R.C., Pennybacker, J.B., & Whitteridge, D. (1941). Akinetic mutism with an epidermoid cyst of the third ventricle. Brain, 64(4), 273–290.
Campagna, J.A., Miller, K.W., & Forman, S.A. (2003). Mechanisms of actions of inhaled anesthetics. New England Journal of Medicine, 348(21), 2110–2124.
Casali, A.G., Gosseries, O., Rosanova, M., Boly, M., Sarasso, S., Casali, K.R., Casarotto, S., Bruno, M.A., Laureys, S., Tononi, G., & Massimini, M. (2013). A theoretically based index of consciousness independent of sensory processing and behavior. Science Translational Medicine, 5(198), 198ra105.
Chatelle, C., Thibaut, A., Bruno, M.-A., Boly, M., Bernard, C., Hustinx, R., Schnakers, C., & Laureys, S. (2014). Nociception coma scale-revised scores correlate with metabolism in the anterior cingulate cortex. Neurorehabilitation and Neural Repair, 28(2), 149–152.
Clement, E.A., Richard, A., Thwaites, M., Ailon, J., Peters, S., & Dickson, C.T. (2008). Cyclic and sleep-like spontaneous alternations of brain state under urethane anaesthesia. PLoS One, 3(4), e2004.
Cole, M.W., & Schneider, W. (2007). The cognitive control network: Integrated cortical regions with dissociable functions. Neuroimage, 37(1), 343–360.
Coleman, M.R., Rodd, J.M., Davis, M.H., Johnsrude, I.S., Menon, D.K., Pickard, J.D., & Owen, A.M. (2007). Do vegetative patients retain aspects of language comprehension? Evidence from fMRI. Brain, 130(10), 2494–2507.
Cruse, D., Chennu, S., Chatelle, C., Bekinschtein, T.A., Fernandez-Espejo, D., Pickard, J.D., Laureys, S., & Owen, A.M. (2011). Bedside detection of awareness in the vegetative state: A cohort study. Lancet, 378(9809), 2088–2094.
Damasio, A., & Meyer, K. (2009). Consciousness: An overview of the phenomenon and of its possible neural basis. In S. Laureys & G. Tononi (Eds.), The neurology of consciousness: Cogntive neuroscience and neuropathology (pp. 3–14). Oxford, UK: Elsevier Ltd.
Davis, M.H., Coleman, M.R., Absalom, A.R., Rodd, J.M., Johnsrude, I.S., Matta, B.F., Owen, A.M., & Menon, D.K. (2007). Dissociating speech perception and comprehension at reduced levels of awareness. Proceedings of the National Academy of Sciences USA, 104(41), 16032–16037.
Dehaene, S., & Changeux, J.-P. (2011). Experimental and theoretical approaches to conscious processing. Neuron, 70(2), 200–227.
Dehaene, S., Changeux, J.-P., Naccache, L., Sackur, J., & Sergent, C. (2006). Conscious, preconscious, and subliminal processing: A testable taxonomy. Trends in Cognitive Sciences, 10(5), 204–211.
Dehaene, S., & Naccache, L. (2001). Towards a cognitive neuroscience of consciousness: Basic evidence and a workspace framework. Cognition, 79(1–2), 1–37.
Del Cul, A., Baillet, S., & Dehaene, S. (2007). Brain dynamics underlying the nonlinear threshold for access to consciousness. PLoS Biology, 5(10), e260.
Demertzi, A., Gosseries, O., Bruno, M.-A., Schnakers, C., Vanhaudenhuyse, A., Chatelle, C., Charland-Verville, V., Thibaut, A., Thonnard, M., & Laureys, S. (2012). The ethics of managing disorders of consciousness. In C. Schnakers & S. Laureys (Eds.), Coma and disorders of consciousness (pp. 147–154). Paris: Springer-Verlag.
Di, H.B., Yu, S.M., Weng, X.C., Laureys, S., Yu, D., Li, J.Q., Qin, P.M., Zhu, Y.H., Zhang, S.Z., & Chen, Y.Z. (2007). Cerebral response to patient’s own name in the vegetative and minimally conscious states. Neurology, 68(12), 895–899.
Edelman, G.M., & Tononi, G. (2000). A universe of consciousness: How matter becomes imagination. New York, NY: Basic Books.
Eikermann, M., Fassbender, P., Zaremba, S., Jordan, A.S., Rosow, C., Malhotra, A., & Chamberlin, N.L. (2009). Pentobarbital dose-dependently increases respiratory genioglossus muscle activity while impairing diaphragmatic function in anesthetized rats. Anesthesiology, 110(6), 1327–1334.
Ferrarelli, F., Massimini, M., Sarasso, S., Casali, A., Riedner, B.A., Angelini, G., Tononi, G., & Pearce, R.A. (2010). Breakdown in cortical effective connectivity during midazolam-induced loss of consciousness. Proceedings of the National Academy of Sciences USA, 107(6), 2681–2686.
Fins, J.J. (2009). The ethics of measuring and modulating consciousness: The imperative of minding time. Progress in Brain Research, 177, 371–382.
Fins, J.J., & Schiff, N.D. (2010). In the blink of the mind’s eye. Hastings Center Report, 40(3), 21–23.
Fiset, P., Paus, T., Daloze, T., Plourde, G., Meuret, P., Bonhomme, V., Hajj-Ali, N., Backman, S.B., & Evans, A.C. (1999). Brain mechanisms of propofol-induced loss of consciousness in humans: A positron emission tomographic study. Journal of Neuroscience, 19(13), 5506–5513.
Fox, M.D., Snyder, A.Z., Vincent, J.L., Corbetta, M., Van Essen, D.C., & Raichle, M.E. (2005). The human brain is intrinsically organized into dynamic, anticorrelated functional networks. Proceedings of the National Academy of Sciences USA, 102(27), 9673–9678.
Giacino, J.T. (1997). Disorders of consciousness: Differential diagnosis and neuropathologic features. Seminars in Neurology, 17(2), 105–111.
Giacino, J.T., Ashwal, S., Childs, N., Cranford, R., Jennett, B., Katz, D.I., Kelly, J.P., Rosenberg, J.H., Whyte, J., Zafonte, R.D., & Zasler, N.D. (2002). The minimally conscious state: Definition and diagnostic criteria. Neurology, 58(3), 349–353.
Giacino, J.T., Hirsch, J., Schiff, N., & Laureys, S. (2006). Functional neuroimaging applications for assessment and rehabilitation planning in patients with disorders of consciousness. Archives of Physical Medicine and Rehabilitation, 87(12 Suppl. 2), S67–S76.
Giacino, J.T., Schnakers, C., Rodriguez-Moreno, D., Kalmar, K., Schiff, N., & Hirsch, J. (2009). Behavioral assessment in patients with disorders of consciousness: Gold standard or fool’s gold? Progress in Brain Research, 177, 33–48.
Goodman, S.J., & Mann, P.E. (1967). Reticular and thalamic multiple unit activity during wakefulness, sleep and anesthesia. Experimental Neurology, 19(1), 11–24.
Gosseries, O., Bruno, M.-A., Chatelle, C., Vanhaudenhuyse, A., Schnakers, C., Soddu, A., & Laureys, S. (2011). Disorders of consciousness: What’s in a name? Neurorehabilitation, 28(1), 3–14.
Gosseries, O., Bruno, M.-A., Vanhaudenhuyse, A., Laureys, S., & Schnakers, C. (2009). Consciousness in the locked-in syndrome. In S. Laureys & G. Tononi (Eds.), The neurology of consciousness: Cognitive neuroscience and neuropathology (pp.191–203). Oxford, UK: Elsevier Ltd.
Gosseries, O., Schnakers, C., Ledoux, D., Vanhaudenhuyse, A., Bruno, M.-A., Demertzi, A., Noirhomme, Q., Lehembre, R., Damas, P., Goldman, S., Peeters, E., Moonen, G., & Laureys, S. (2011). Automated EEG entropy measurements in coma, vegetative state/unresponsive wakefulness syndrome and minimally conscious state. Functional Neurology, 26(1), 25–30.
Gosseries, O., Zasler, N.D., & Laureys, S. (2014). Recent advances in disorders of consciousness: Focus on the diagnosis. Brain Injury, 28(9), 1141–1150.
Greicius, M.D., Kiviniemi, V., Tervonen, O., Vainionpää, V., Alahuhta, S., Reiss, A.L., & Menon, V. (2008). Persistent default-mode network connectivity during light sedation. Human Brain Mapping, 29(7), 839–847.
Gugino, L.D., Chabot, R.J., Prichep, L.S., John, E.R., Formanek, V., & Aglio, L.S. (2001). Quantitative EEG changes associated with loss and return of consciousness in healthy adult volunteers anaesthetized with propofol or sevoflurane. British Journal of Anaesthesia, 87(3), 421–428.
Guldenmund, P., Vanhaudenhuyse, A., Boly, M., Laureys, S., & Soddu, A. (2012). A default mode of brain function in altered states of consciousness. Archives Italiennes de Biologie, 150(2–3), 107–121.
Heine, L., Soddu, A., Gomez, F., Vanhaudenhuyse, A., Tshibanda, L., Thonnard, M., Charland-Verville, V., Kirsch, M., Laureys, S., & Demertzi, A. (2012). Resting state networks and consciousness: Alterations of multiple resting state network connectivity in physiological, pharmacological, and pathological consciousness states. Frontiers in Psychology, 3, 295.
Heinke, W., Fiebach, C.J., Schwarzbauer, C., Meyer, M., Olthoff, D., & Alter, K. (2004). Sequential effects of propofol on functional brain activation induced by auditory language processing: An event-related functional magnetic resonance imaging study. British Journal of Anaesthesia, 92(5), 641–650.
Horovitz, S.G., Braun, A.R., Carr, W.S., Picchioni, D., Balkin, T.J., Fukunaga, M., & Duyn, J.H. (2009). Decoupling of the brain’s default mode network during deep sleep. Proceedings of the National Academy of Sciences USA, 106(27), 11376–11381.
Jennett, B., & Plum, F. (1972). Persistent vegetative state after brain damage. A syndrome in search of a name. Lancet, 1(7753), 734–737.
John, E.R., & Prichep, L.S. (2005). The anesthetic cascade: A theory of how anesthesia suppresses consciousness. Anesthesiology, 102(2), 447–471.
Kaisti, K.K., Langsjo, J.W., Aalto, S., Oikonen, V., Sipila, H., Teras, M., Hinkka, S., Metsähonkala, L., & Scheinin, H. (2003). Effects of sevoflurane, propofol, and adjunct nitrous oxide on regional cerebral blood flow, oxygen consumption, and blood volume in humans. Anesthesiology, 99(3), 603–613.
Keifer, J.C., Baghdoyan, H.A., & Lydic, R. (1996). Pontine cholinergic mechanisms modulate the cortical electroencephalographic spindles of halothane anesthesia. Anesthesiology, 84(4), 945–954.
Laird, A.R., Fox, P.M., Eickhoff, S.B., Turner, J.A., Ray, K.L., Mckay, D.R., Glahn, D.C., Beckmann, C.F., Smith, S.M., & Fox, P.T. (2011). Behavioral interpretations of intrinsic connectivity networks. Journal of Cognitive Neuroscience, 23(12), 4022–4037.
Larson-Prior, L.J., Zempel, J.M., Nolan, T.S., Prior, F.W., Snyder, A.Z., & Raichle, M.E. (2009). Cortical network functional connectivity in the descent to sleep. Proceedings of the National Academy of Sciences USA, 106(11), 4489–4494.
Laureys, S. (2004). Functional neuroimaging in the vegetative state. Neurorehabilitation, 19(4), 335–341.
. (2005). The neural correlate of (un)awareness: Lessons from the vegetative state. Trends in Cognitive Sciences, 9(12), 556–559.
Laureys, S., Berré, J., & Goldman, S. (2001). Cerebral function in coma, vegetative state, minimally conscious state, locked-in syndrome and brain death. In J.L. Vincent (Ed.), Yearbook of intensive care and emergency medicine (pp. 386–396). Berlin: Springer-Verlag.
Laureys, S., Celesia, G.G., Cohadon, F., Lavrijsen, J., León-Carrión, J., Sannita, W.G., Sazbon, L., Schmutzhard, E., von Wild, K.R., Zeman, A., & Dolce, G. (2010). Unresponsive wakefulness syndrome: A new name for the vegetative state or apallic syndrome. BMC Medicine, 8, 68.
Laureys, S., Faymonville, M.-E., Degueldre, C., Fiore, G.D., Damas, P., Lambermont, B., Janssens, N., Aerts, J., Franck, G., Luxen, A., Moonen, G., Lamy, M., & Maquet, P. (2000). Auditory processing in the vegetative state. Brain, 123(8), 1589–1601.
Laureys, S., Faymonville, M.-E., Goldman, S., Degueldre, C., Phillips, C., Lambermont, B., Aerts, J., Lamy, M., Luxen, A., Franck, G., & Maquet, P. (2000). Impaired cerebral connectivity in vegetative state. In A. Gjedde, S.B. Hansen, G.M. Knudsen, & O.B. Paulson (Eds.), Physiological imaging of the brain with PET (pp.329–334). San Diego, CA: Academic Press.
Laureys, S., Faymonville, M.-E., Luxen, A., Lamy, M., Franck, G., & Maquet, P. (2000). Restoration of thalamocortical connectivity after recovery from persistent vegetative state. Lancet, 355(9217), 1790–1791.
Laureys, S., Goldman, S., Phillips, C., Van Bogaert, P., Aerts, J., Luxen, A., Franck, G., & Maquet, P. (1999). Impaired effective cortical connectivity in vegetative state: Preliminary investigation using PET. Neuroimage, 9(4), 377–382.
Laureys, S., Lemaire, C., Maquet, P., Phillips, C., & Franck, G. (1999). Cerebral metabolism during vegetative state and after recovery to consciousness. Journal of Neurology, Neurosurgery & Psychiatry, 67(1), 121–122.
Laureys, S., Owen, A.M., & Schiff, N.D. (2004). Brain function in coma, vegetative state, and related disorders. Lancet Neurology, 3(9), 537–546.
Laureys, S., Pellas, F., Van Eeckhout, P., Ghorbel, S., Schnakers, C., Perrin, F., Berré, J., Faymonville, M.E., Pantke, K.H., Damas, F., Lamy, M., Moonen, G., & Goldman, S. (2005). The locked-in syndrome: What is it like to be conscious but paralyzed and voiceless? Progress in Brain Research, 150, 495–511.
Laureys, S., Perrin, F., Faymonville, M.-E., Schnakers, C., Boly, M., Bartsch, V., Majerus, S., Moonen, G., & Maquet, P. (2004). Cerebral processing in the minimally conscious state. Neurology, 63(5), 916–918.
Laureys, S., & Schiff, N.D. (2012). Coma and consciousness: Paradigms (re)framed by neuroimaging. Neuroimage, 61(2), 478–491.
Lehembre, R., Bruno, M.-A., Vanhaudenhuyse, A., Chatelle, C., Cologan, V., Leclercq, Y., Soddu, A., Macq, B., Laureys, S., & Noirhomme, Q. (2012). Resting-state EEG study of comatose patients: A connectivity and frequency analysis to find differences between vegetative and minimally conscious states. Functional Neurology, 27(1), 41–47.
Lehembre, R., Gosseries, O., Lugo, Z., Jedidi, Z., Chatelle, C., Sadzot, B., Laureys, S., & Noirhomme, Q. (2012). Electrophysiological investigations of brain function in coma, vegetative and minimally conscious patients. Archives Italiennes de Biologie, 150(2–3), 122–139.
Leslie, K., Sleigh, J., Paech, M.J., Voss, L., Lim, C.W., & Sleigh, C. (2009). Dreaming and electroencephalographic changes during anesthesia maintained with propofol or desflurane. Anesthesiology, 111(3), 547–555.
Luauté, J., Maucort-Boulch, D., Tell, L., Quelard, F., Sarraf, T., Iwaz, J., Boisson, D., & Fischer, C. (2010). Long-term outcomes of chronic minimally conscious and vegetative states. Neurology, 75(3), 246–252.
Lull, N., Noe, E., Lull, J.J., Garcia-Panach, J., Chirivella, J., Ferri, J., López-Aznar, D., Sopena, P., & Robles, M. (2010). Voxel-based statistical analysis of thalamic glucose metabolism in traumatic brain injury: Relationship with consciousness and cognition. Brain Injury, 24(9), 1098–1107.
Lydic, R., & Baghdoyan, H.A. (2005). Sleep, anesthesiology, and the neurobiology of arousal state control. Anesthesiology, 103(6), 1268–1295.
Majerus, S., Gill-Thwaites, H., Andrews, K., & Laureys, S. (2005). Behavioral evaluation of consciousness in severe brain damage. Progress in Brain Research, 150, 397–413.
Maquet, P. (2010). Understanding non rapid eye movement sleep through neuroimaging. World Journal of Biological Psychiatry, 11(Suppl. 1), 9–15.
Maquet, P., Dive, D., Salmon, E., Sadzot, B., Franco, G., Poirrier, R., von Frenckell, R., & Franck, G. (1990). Cerebral glucose utilization during sleep-wake cycle in man determined by positron emission tomography and [18F]2-fluoro-2-deoxy-d-glucose method. Brain Research, 513(1), 136–143.
Maquet, P., Ruby, P., Maudoux, A., Albouy, G., Sterpenich, V., Dang-Vu, T., Desseilles, M., Boly, M., Perrin, F., Peigneux, P., & Laureys, S. (2005). Human cognition during REM sleep and the activity profile within frontal and parietal cortices: A reappraisal of functional neuroimaging data. Progress in Brain Research, 150, 219–227.
Massimini, M., Boly, M., Casali, A., Rosanova, M., & Tononi, G. (2009). A perturbational approach for evaluating the brain’s capacity for consciousness. Progress in Brain Research, 177, 201–214.
Massimini, M., Ferrarelli, F., Huber, R., Esser, S.K., Singh, H., & Tononi, G. (2005). Breakdown of cortical effective connectivity during sleep. Science, 309(5744), 2228–2232.
Massimini, M., Ferrarelli, F., Murphy, M., Huber, R., Riedner, B., Casarotto, S., & Tononi, G. (2010). Cortical reactivity and effective connectivity during REM sleep in humans. Cognitive Neuroscience, 1(3), 176–183.
Menon, V., & Uddin, L.Q. (2010). Saliency, switching, attention and control: A network model of insula function. Brain Structure & Function, 214(5–6), 655–667.
Monti, M.M., Vanhaudenhuyse, A., Coleman, M.R., Boly, M., Pickard, J.D., Tshibanda, L., Owen, A.M., & Laureys, S. (2010). Willful modulation of brain activity in disorders of consciousness. New England Journal of Medicine, 362(7), 579–589.
Murphy, M., Bruno, M.-A., Riedner, B.A., Boveroux, P., Noirhomme, Q., Landsness, E.C., Brichant, J.F., Phillips, C., Massimini, M., Laureys, S., Tononi, G., & Boly, M. (2011). Propofol anesthesia and sleep: A high-density EEG study. Sleep, 34(3), 283–291.
Murphy, M., Riedner, B.A., Huber, R., Massimini, M., Ferrarelli, F., & Tononi, G. (2009). Source modeling sleep slow waves. Proceedings of the National Academy of Sciences USA, 106(5), 1608–1613.
Naci, L., Cusack, R., Jia, V.Z., & Owen, A.M. (2013). The brain’s silent messenger: Using selective attention to decode human thought for brain-based communication. Journal of Neuroscience, 33(22), 9385–9393.
Nir, Y., & Tononi, G. (2010). Dreaming and the brain: From phenomenology to neurophysiology. Trends in Cognitive Sciences, 14(2), 88–100.
Owen, A.M., Coleman, M.R., Boly, M., Davis, M.H., Laureys, S., & Pickard, J.D. (2006). Detecting awareness in the vegetative state. Science, 313(5792), 1402.
Perrin, F., Schnakers, C., Schabus, M., Degueldre, C., Goldman, S., Bredart, S., Faymonville, M.E., Lamy, M., Moonen, G., Luxen, A., Maquet, P., & Laureys, S. (2006). Brain response to one’s own name in vegetative state, minimally conscious state, and locked-in syndrome. Archives of Neurology, 63(4), 562–569.
Phillips, C.L., Bruno, M.-A., Maquet, P., Boly, M., Noirhomme, Q., Schnakers, C., Vanhaudenhuyse, A., Bonjean, M., Hustinx, R., Moonen, G., Luxen, A., & Laureys, S. (2011). “Relevance vector machine” consciousness classifier applied to cerebral metabolism of vegetative and locked-in patients. Neuroimage, 56(2), 797–808.
Ploner, M., Lee, M.C., Wiech, K., Bingel, U., & Tracey, I. (2010). Prestimulus functional connectivity determines pain perception in humans. Proceedings of the National Academy of Sciences USA, 107(1), 355–360.
Plourde, G., Belin, P., Chartrand, D., Fiset, P., Backman, S.B., Xie, G., & Zatorre, R.J. (2006). Cortical processing of complex auditory stimuli during alterations of consciousness with the general anesthetic propofol. Anesthesiology, 104(3), 448–457.
Posner, J.B., Saper, C.B., Schiff, N.D., & Plum, F. (2007). Plum and Posner’s diagnosis of stupor and coma. New York, NY: Oxford University Press.
Raichle, M.E., MacLeod, A.M., Snyder, A.Z., Powers, W.J., Gusnard, D.A., & Shulman, G.L. (2001). A default mode of brain function. Proceedings of the National Academy of Sciences USA, 98(2), 676–682.
Rechtshaffen, A. (1973). The psychophysiology of mental activity during sleep. In F. McGuigan & R. Schoonover (Eds.), The psychophysiology of thinking: Studies of covert processes (pp.153–205). Ann Arbor, MI: Academic Press.
Rex, S., Meyer, P.T., Baumert, J.H., Rossaint, R., Fries, M., Bull, U., & Schaefer, W.M. (2008). Positron emission tomography study of regional cerebral blood flow and flow-metabolism coupling during general anaesthesia with xenon in humans. British Journal of Anaesthesia, 100(5), 667–675.
Riedner, B.A., Vyazovskiy, V.V., Huber, R., Massimini, M., Esser, S., Murphy, M., & Tononi, G. (2007). Sleep homeostasis and cortical synchronization: III. A high-density EEG study of sleep slow waves in humans. Sleep, 30(12), 1643–1657.
Roberts, K.L., & Hall, D.A. (2008). Examining a supramodal network for conflict processing: A systematic review and novel functional magnetic resonance imaging data for related visual and auditory stroop tasks. Journal of Cognitive Neuroscience, 20(6), 1063–1078.
Rodriguez-Moreno, D., Schiff, N.D., Giacino, J., Kalmar, K., & Hirsch, J. (2010). A network approach to assessing cognition in disorders of consciousness. Neurology, 75(21), 1871–1878.
Rosanova, M., Gosseries, O., Casarotto, S., Boly, M., Casali, A.G., Bruno, M.-A., Mariotti, M., Boveroux, P., Tononi, G., Laureys, S., & Massimini, M. (2012). Recovery of cortical effective connectivity and recovery of consciousness in vegetative patients. Brain, 135(4), 1308–1320.
Rowley, G., & Fielding, K. (1991). Reliability and accuracy of the Glasgow Coma Scale with experienced and inexperienced users. Lancet, 337(8740), 535–538.
Samann, P.G., Wehrle, R., Hoehn, D., Spoormaker, V.I., Peters, H., Tully, C., Holsboer, F., & Czisch, M. (2011). Development of the brain’s default mode network from wakefulness to slow wave sleep. Cerebral Cortex, 21(9), 2082–2093.
Sanders, R.D., Tononi, G., Laureys, S., & Sleigh, J.W. (2012). Unresponsiveness not equal unconsciousness. Anesthesiology, 116(4), 946–959.
Schiff, N.D. (2006). Multimodal neuroimaging approaches to disorders of consciousness. Jouranl of Head Trauma Rehabilitation, 21(5), 388–397.
Schiff, N.D., Giacino, J.T., Kalmar, K., Victor, J.D., Baker, K., Gerber, M., Fritz, B., Eisenberg, B., Biondi, T., O’Connor, J., Kobylarz, E.J., Farris, S., Machado, A., McCagg, C., Plum, F., Fins, J.J., & Rezai, A.R. (2007). Behavioural improvements with thalamic stimulation after severe traumatic brain injury. Nature, 448(7153), 600–603.
Schiff, N.D., Rodriguez-Moreno, D., Kamal, A., Kim, K.H., Giacino, J.T., Plum, F., & Hirsch, J. (2005). fMRI reveals large-scale network activation in minimally conscious patients. Neurology, 64(3), 514–523.
Schnakers, C. (2012). Clinical assessment of patients with disorders of consciousness. Archives Italiennes de Biologie, 150(2–3), 36–43.
Schnakers, C., Giacino, J., Kalmar, K., Piret, S., Lopez, E., Boly, M., Malone, R., & Laureys, S. (2006). Does the FOUR score correctly diagnose the vegetative and minimally conscious states? Annals of Neurology, 60(6), 744–745.
Schnakers, C., Ledoux, D., Majerus, S., Damas, P., Damas, F., Lambermont, B., Lamy, M., Boly, M., Vanhaudenhuyse, A., Moonen, G., & Laureys, S. (2008). Diagnostic and prognostic use of bispectral index in coma, vegetative state and related disorders. Brain Injury, 22(12), 926–931.
Schnakers, C., Perrin, F., Schabus, M., Hustinx, R., Majerus, S., Moonen, G., Boly, M., Vanhaudenhuyse, A., Bruno, M.A., & Laureys, S. (2009). Detecting consciousness in a total locked-in syndrome: An active event-related paradigm. Neurocase, 15(4), 271–277.
Schnakers, C., Perrin, F., Schabus, M., Majerus, S., Ledoux, D., Damas, P., Boly, M., Vanhaudenhuyse, A., Bruno, M.A., Moonen, G., & Laureys, S. (2008). Voluntary brain processing in disorders of consciousness. Neurology, 71(20), 1614–1620.
Schnakers, C., Vanhaudenhuyse, A., Giacino, J., Ventura, M., Boly, M., Majerus, S., Moonen, G., & Laureys, S. (2009). Diagnostic accuracy of the vegetative and minimally conscious state: Clinical consensus versus standardized neurobehavioral assessment. BMC Neurology, 9, 35.
Schwartz, J., & Roth, T. (2008). Neurophysiology of sleep and wakefulness: Basic science and clinical implications. Current Neuropharmacology, 6(4), 367–378.
Seel, R.T., Sherer, M., Whyte, J., Katz, D.I., Giacino, J.T., Rosenbaum, A.M., Hammond, F.M., Kalmar, K., Pape, T.L., Zafonte, R., Biester, R.C., Kaelin, D., Kean, J., & Zasler, N. (2010). Assessment scales for disorders of consciousness: Evidence-based recommendations for clinical practice and research. Archives of Physical Medecine and Rehabilitation, 91(12), 1795–1813.
Seeley, W.W., Menon, V., Schatzberg, A.F., Keller, J., Glover, G.H., Kenna, H., Reiss, A.L., & Greicius, M.D. (2007). Dissociable intrinsic connectivity networks for salience processing and executive control. Journal of Neuroscience, 27(9), 2349–2356.
Siclari, F., Larocque, J.J., Postle, B.R., & Tononi, G. (2013). Assessing sleep consciousness within subjects using a serial awakening paradigm. Frontiers in Psychology, 4, 542.
Silva, S., Alacoque, X., Fourcade, O., Samii, K., Marque, P., Woods, R., Mazziotta, J., Chollet F., & Loubinoux, I. (2010). Wakefulness and loss of awareness: Brain and brainstem interaction in the vegetative state. Neurology, 74(4), 313–320.
Sleigh, J.W., Andrzejowski, J., Steyn-Ross, A., & Steyn-Ross, M. (1999). The bispectral index: A measure of depth of sleep? Anesthesia and Analgesia, 88(3), 659–661.
Smith, S.M., Fox, P.T., Miller, K.L., Glahn, D.C., Fox, M.P., Mackay, C.E., Filippini, N., Watkins, K.E., Toro, R., Laird, A.R., & Beckmann, C.F. (2009). Correspondence of the brain’s functional architecture during activation and rest. Proceedings of the National Academy of Sciences USA, 106(31), 13040–13045.
Steriade, M. (1996). Arousal: Revisiting the reticular activating system. Science, 272(5259), 225–226.
Stickgold, R., Malia, A., Fosse, R., Propper, R., & Hobson, J.A. (2001). Brain-mind states: I. Longitudinal field study of sleep/wake factors influencing mentation report length. Sleep, 24(2), 171–179.
Teasdale, G., & Jennett, B. (1974). Assessment of coma and impaired consciousness. A practical scale. Lancet, 2(7872), 81–84.
. (2008). Consciousness as integrated information: A provisional manifesto. Biological Bulletin, 215(3), 216–242.
. (2012). Integrated information theory of consciousness: An updated account. Archives Italiennes de Biologie, 150(4), 293–329.
Tononi, G., & Laureys, S. (2009). The neurology of consciousness: An overview. In S. Laureys & G. Tononi (Eds.), The neurology of consciousness: Cogntive neuroscience and neuropathology (pp.375–412). Oxford, UK: Elsevier Ltd.
Vanhaudenhuyse, A., Demertzi, A., Schabus, M., Noirhomme, Q., Bredart, S., Boly, M., Phillips, C., Soddu, A., Luxen, A., Moonen, G., & Laureys, S. (2011). Two distinct neuronal networks mediate the awareness of environment and of self. Journal of Cognitive Neuroscience, 23(3), 570–578.
Vanhaudenhuyse, A., Laureys, S., & Perrin, F. (2008). Cognitive event-related potentials in comatose and post-comatose states. Neurocritical Care, 8(2), 262–270.
Vanhaudenhuyse, A., Noirhomme, Q., Tshibanda, L.J., Bruno, M.-A., Boveroux, P., Schnakers, C., Soddu, A., Perlbarg, V., Ledoux, D., Brichant, J.F., Moonen, G., Maquet, P., Greicius, M.D., Laureys, S., & Boly, M. (2010). Default network connectivity reflects the level of consciousness in non-communicative brain-damaged patients. Brain, 133(1), 161–171.
Velly, L.J., Rey, M.F., Bruder, N.J., Gouvitsos, F.A., Witjas, T., Regis, J.M., Peragut, J.C., & Gouin, F.M. (2007). Differential dynamic of action on cortical and subcortical structures of anesthetic agents during induction of anesthesia. Anesthesiology, 107(2), 202–212.
Veselis, R.A., Feshchenko, V.A., Reinsel, R.A., Beattie, B., & Akhurst, T.J. (2005). Propofol and thiopental do not interfere with regional cerebral blood flow response at sedative concentrations. Anesthesiology, 102(1), 26–34.
Veselis, R.A., Feshchenko, V.A., Reinsel, R.A., Dnistrian, A.M., Beattie, B., & Akhurst, T.J. (2004). Thiopental and propofol affect different regions of the brain at similar pharmacologic effects. Anesthesia and Analgesia, 99(2), 399–408.
Vogel, D., Markl, A., Yu, T., Kotchoubey, B., Lang, S., & Müller, F. (2013). Can mental imagery functional magnetic resonance imaging predict recovery in patients with disorders of consciousness? Archives of Physical Medicine and Rehabilitation, 94(10), 1891–1898.
Vogt, B.A., & Laureys, S. (2005). Posterior cingulate, precuneal and retrosplenial cortices: Cytology and components of the neural network correlates of consciousness. Progress in Brain Research, 150, 205–217.
White, N.S., & Alkire, M.T. (2003). Impaired thalamocortical connectivity in humans during general-anesthetic-induced unconsciousness. Neuroimage, 19(2), 402–411.
Wiech, K., Lin, C.S., Brodersen, K.H., Bingel, U., Ploner, M., & Tracey, I. (2010). Anterior insula integrates information about salience into perceptual decisions about pain. Journal of Neuroscience, 30(48), 16324–16331.