[en] Background. Despite recent evidence suggesting that some severely brain-injured patients retain some capacity for topdown
processing (covert cognition), the degree of sparing is unknown. Objective. Top-down attentional processing was
assessed in patients in minimally conscious (MCS) and vegetative states (VS) using an active event-related potential (ERP)
paradigm. Methods. A total of 26 patients were included (38 ± 12 years old, 9 traumatic, 21 patients >1 year postonset):
8 MCS+, 8 MCS−, and 10 VS patients. There were 14 healthy controls (30 ± 8 years old). The ERP paradigm included
(1) a passive condition and (2) an active condition, wherein the participant was instructed to voluntarily focus attention
on his/her own name. In each condition, the participant’s own name was presented 100 times (ie, 4 blocks of 25 stimuli).
Results. In 5 MCS+ patients as well as in 3 MCS− patients and 1 VS patient, an enhanced P3 amplitude was observed in
the active versus passive condition. Relative to controls, patients showed a response that was (1) widely distributed
over frontoparietal areas and (2) not present in all blocks (3 of 4). In patients with covert cognition, the amplitude of the
response was lower in frontocentral electrodes compared with controls but did not differ from that in the MCS+ group.
Conclusion. The results indicate that volitional top-down attention is impaired in patients with covert cognition. Further
investigation is crucially needed to better understand top-down cognitive functioning in this population because this may
help refine brain-computer interface–based communication strategies.
Research Center/Unit :
Centre, University of Liège and University Hospital of Liège, Sart Tilman,
Owen AM, Coleman MR, Boly M, et al. Detecting awareness in the vegetative state. Science. 2006 1402 ; 313 :
Monti MM, Vanhaudenhuyse A, Coleman MR, et al. Willful modulation of brain activity in disorders of consciousness. N Engl J Med. 2010 ; 362: 579-589
Cruse D, Chennu S, Chatelle C, et al. Bedside detection of awareness in the vegetative state: a cohort study. Lancet. 2011 ; 378: 2088-2094
Cruse D, Chennu S, Chatelle C, et al. Relationship between etiology and covert cognition in the minimally conscious state. Neurology. 2012 ; 78: 816-822
Schnakers C, Perrin F, Schabus M, et al. Voluntary brain processing in disorders of consciousness. Neurology. 2008 ; 71: 1614-1620
Faugeras F, Rohaut B, Weiss N, et al. Probing consciousness with event-related potentials in the vegetative state. Neurology. 2011 ; 77: 264-268
Goldfine AM, Victor JD, Conte MM, et al. Determination of awareness in patients with severe brain injury using EEG power spectral analysis. Clin Neurophysiol. 2011 ; 122: 2157-2168
Lechinger J, Chwala-Schlegel N, Fellinger R, et al. Mirroring of a simple motor behavior in disorders of consciousness. Clin Neurophysiol. 2013 ; 124: 27-34
Monti MM. Annu Rev Clin Psychol. 2012 ; 8: 431-454
Medical aspects of the persistent vegetative state. N Engl J Med. 1994 ; 330: 1499-1508
Giacino JT, Ashwal S, Childs N, et al. The minimally conscious state: definition and diagnostic criteria. Neurology. 2002 ; 58: 349-353
Nachev P, Hacker PM. Covert cognition in the persistent vegetative state. Prog Neurobiol. 2010 ; 91: 68-76
Kübler A, Kotchoubey B. Brain-computer interfaces in the continuum of consciousness. Curr Opin Neurol. 2007 ; 20: 643-649
Naci L, Monti MM, Cruse D, et al. Brain-computer interfaces for communication with nonresponsive patients. Ann Neurol. 2012 ; 72: 312-323
Chennu S, Finoia P, Kamau E, et al. Dissociable endogenous and exogenous attention in disorders of consciousness. Neuroimage Clin. 2013 ; 3: 450-461
Posner MI. Attentional networks and consciousness. Front Psychol. 2012 ; 3: 64
Fan J, Gu X, Guise KG, et al. Testing the behavioral interaction and integration of attentional networks. Brain Cogn. 2009 ; 70: 209-220
Laureys S, Schiff ND. Coma and consciousness: paradigms (re)framed by neuroimaging. Neuroimage. 2012 ; 61: 478-491
Perrin F, García-Larrea L, Mauguière F, et al. A differential brain response to the subject's own name persists during sleep. Clin Neurophysiol. 1999 ; 110: 2153-2164
Davis MH, Coleman MR, Absalom AR, et al. Dissociating speech perception and comprehension at reduced levels of awareness. Proc Natl Acad Sci U S A. 2007 ; 104: 16032-16037
Corbetta M, Shulman GL. Control of goal-directed and stimulus-driven attention in the brain. Nat Rev Neurosci. 2002 ; 3: 201-215
Posner MI, Sheese BE, Odludas Y, et al. Analyzing and shaping human attentional networks. Neural Netw. 2006 ; 19: 1422-1429
Wood N, Cowan N. The cocktail party phenomenon revisited: how frequent are attention shifts to one's name in an irrelevant auditory channel?. J Exp Psychol Learn Mem Cogn. 1995 ; 21: 255-260
Baluch F, Itti L. Mechanisms of top-down attention. Trends Neurosci. 2011 ; 34: 210-224
Polich J. Updating P300: an integrative theory of P3a and P3b. Clin Neurophysiol. 2007 ; 118: 2128-2148
Giacino JT, Kalmar K, Whyte J. The JFK Coma Recovery Scale-Revised: measurement characteristics and diagnostic utility. Arch Phys Med Rehabil. 2004 ; 85: 2020-2029
Løvstad M, Frøslie KF, Giacino JT, et al. Reliability and diagnostic characteristics of the JFK coma recovery scale-revised: exploring the influence of rater's level of experience. J Head Trauma Rehabil. 2010 ; 25: 349-356
La Porta F, Caselli S, Ianes AB, et al. Can we scientifically and reliably measure the level of consciousness in vegetative and minimally conscious states? Rasch analysis of the Coma Recovery Scale-Revised. Arch Phys Med Rehabil. 2013 ; 94: 527-535
Bruno MA, Majerus S, Boly M, et al. Functional neuroanatomy underlying the clinical subcategorization of minimally conscious state patients. J Neurol. 2012 ; 259: 1087-1098
Klem GH, Luders HO, Jasper HH, et al. The ten-twenty electrode system of the International Federation. The International Federation of Clinical Neurophysiology. Electroencephalogr Clin Neurophysiol Suppl. 1999 ; 52: 3-6
Herrmann CS, Knight RT. Mechanisms of human attention: event-related potentials and oscillations. Neurosci Biobehav. 2001 ; 25: 465-476
Polich J, Eischen SE, Collins GE. P300 from a single auditory stimulus. Electroencephalogr Clin Neurophysiol. 1994 ; 92: 253-261
Mertens R, Polich J. P300 from a single-stimulus paradigm: passive versus active tasks and stimulus modality. Electroencephalogr Clin Neurophysiol. 1997 ; 104: 488-497
Cass M, Polich J. P300 from a single-stimulus paradigm: auditory intensity and tone frequency effects. Biol Psychol. 1997 ; 46: 51-65
Polich J, Margala C. P300 and probability: comparison of oddball and single-stimulus paradigms. Int J Psychophysiol. 1997 ; 25: 169-176
Croft RJ, Gonsalvez CJ, Gabriel C, et al. Target-to-target interval versus probability effects on P300 in one- and two-tone tasks. Psychophysiology. 2003 ; 40: 322-328
Folmer RL, Yingling CD. Auditory P3 responses to name stimuli. Brain Lang. 1997 ; 56: 306-311
Boly M, Garrido MI, Gosseries O, et al. Preserved feedforward but impaired top-down processes in the vegetative state. Science. 2011 ; 332: 858-862
Katayama J, Polich J. Stimulus context determines P3a and P3b. Psychophysiology. 1998 ; 35: 23-33
Petersen SE, Posner MI. The attention system of the human brain: 20 years after. Annu Rev Neurosci. 2012 ; 35: 73-89
Bruno MA, Vanhaudenhuyse A, Thibaut A, et al. From unresponsive wakefulness to minimally conscious PLUS and functional locked-in syndromes: recent advances in our understanding of disorders of consciousness. J Neurol. 2011 ; 258: 1373-1384
Perrin F, Schnakers C, Schabus M, et al. Brain response to one's own name in vegetative state, minimally conscious state, and locked-in syndrome. Arch Neurol. 2006 ; 63: 562-569
Duncan CC, Barry RJ, Connolly JF, et al. Event-related potentials in clinical research: guidelines for eliciting, recording, and quantifying mismatch negativity, P300, and N400. Clin Neurophysiol. 2009 ; 120: 1883-1908
Eichenlaub JB, Ruby P, Morlet D. What is the specificity of the response to the own first-name when presented as a novel in a passive oddball paradigm? An ERP study. Brain Res. 2012 ; 1447: 65-78
Yeomans JS, Frankland PW. The acoustic startle reflex: neurons and connections. Brain Res Rev. 1995 ; 21: 301-314
Knight RT, Hillyard SA, Woods DL, et al. The effects of frontal and temporal-parietal lesions on the auditory evoked potential in man. Electroencephalogr Clin Neurophysiol. 1980 ; 50: 112-124
Leon-Carrion L, Martin-Rodriguez JF, Damas-Lopez J, et al. Brain function in the minimally conscious state: a quantitative neurophysiological study. Clin Neurophysiol. 2008 ; 119: 1506-1514
Lehembre R, Bruno MA, Vanhaudenhuyse A, et al. Resting-state EEG study of comatose patients: a connectivity and frequency analysis to find differences between vegetative and minimally conscious states. Funct Neurol. 2012 ; 27: 41-47
Lulé D, Noirhomme Q, Kleih SC, et al. Probing command following in patients with disorders of consciousness using a brain-computer interface. Clin Neurophysiol. 2013 ; 124: 101-106
