[en] 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.
Disciplines :
Anesthesia & intensive care Neurology
Author, co-author :
Bruno, Marie-Aurélie ; Université de Liège - ULiège > Centre de recherches du cyclotron
Majerus, Steve ; Université de Liège - ULiège > Département de Psychologie : cognition et comportement > Psychopathologie cognitive
Boly, Mélanie ; Université de Liège - ULiège > Département des sciences cliniques > Neurologie
JT Giacino S Ashwal N Childs, et al. 2002 The minimally conscious state: definition and diagnostic criteria Neurology 58 349 353 11839831 10.1212/WNL.58.3.349
Bruno MA, Vanhaudenhuyse A, Thibaut A et al (2011) From unresponsive wakefulness to minimally conscious PLUS and functional locked-in syndromes: recent advances in our understanding of disorders of consciousness. J Neurol
S Laureys S Goldman C Phillips, et al. 1999 Impaired effective cortical connectivity in vegetative state: preliminary investigation using PET Neuroimage 9 377 382 10191166 10.1006/nimg.1998.0414 1:STN:280:DyaK1M3gvVygtw%3D%3D
JT Giacino K Kalmar J Whyte 2004 The JFK Coma Recovery Scale-Revised: measurement characteristics and diagnostic utility Arch Phys Med Rehabil 85 2020 2029 15605342 10.1016/j.apmr.2004.02.033
S Laureys ME Faymonville C Degueldre, et al. 2000 Auditory processing in the vegetative state Brain 123 1589 1601 10908189 10.1093/brain/123.8.1589
CR Genovese NA Lazar T Nichols 2002 Thresholding of statistical maps in functional neuroimaging using the false discovery rate Neuroimage 15 870 878 11906227 10.1006/nimg.2001.1037
N Nakayama A Okumura J Shinoda, et al. 2006 Relationship between regional cerebral metabolism and consciousness disturbance in traumatic diffuse brain injury without large focal lesions: an FDG-PET study with statistical parametric mapping analysis J Neurol Neurosurg Psychiatr 77 856 862 16549415 10.1136/jnnp.2005.080523 1:STN:280:DC%2BD28znt1Ohsg%3D%3D
J Rudolf M Ghaemi M Ghaemi, et al. 1999 Cerebral glucose metabolism in acute and persistent vegetative state J Neurosurg Anesthesiol 11 17 24 9890381 10.1097/00008506-199901000-00004 1:STN:280:DyaK1M7gsFertQ%3D%3D
HU Voss AM Uluc JP Dyke, et al. 2006 Possible axonal regrowth in late recovery from the minimally conscious state J Clin Invest 116 2005 2011 16823492 10.1172/JCI27021 1:CAS:528:DC%2BD28XmvV2lurc%3D
A Vanhaudenhuyse Q Noirhomme LJ Tshibanda, et al. 2010 Default network connectivity reflects the level of consciousness in non-communicative brain-damaged patients Brain 133 161 171 20034928 10.1093/brain/awp313
S Laureys 2005 The neural correlate of (un)awareness: lessons from the vegetative state Trends Cogn Sci 9 556 559 16271507 10.1016/j.tics.2005.10.010
M Boly ME Faymonville C Schnakers, et al. 2008 Perception of pain in the minimally conscious state with PET activation: an observational study Lancet Neurol 7 1013 1020 18835749 10.1016/S1474-4422(08)70219-9
S Laureys ME Faymonville P Peigneux, et al. 2002 Cortical processing of noxious somatosensory stimuli in the persistent vegetative state Neuroimage 17 732 741 12377148 10.1006/nimg.2002.1236 1:STN:280:DC%2BD38nitV2qtA%3D%3D
M Boly ME Faymonville P Peigneux, et al. 2004 Auditory processing in severely brain injured patients: differences between the minimally conscious state and the persistent vegetative state Arch Neurol 61 233 238 14967772 10.1001/archneur.61.2.233
MR Coleman JM Rodd MH Davis, et al. 2007 Do vegetative patients retain aspects of language comprehension? Evidence from fMRI Brain 130 2494 2507 17827174 10.1093/brain/awm170
S Laureys F Perrin ME Faymonville, et al. 2004 Cerebral processing in the minimally conscious state Neurology 63 916 918 15365150 10.1212/01.WNL. 0000137421.30792.9B 1:STN:280:DC%2BD2cvls12itA%3D%3D
ND Schiff D Rodriguez-Moreno A Kamal, et al. 2005 fMRI reveals large-scale network activation in minimally conscious patients Neurology 64 514 523 15699384 10.1212/01.WNL.0000150883.10285.44 1:STN:280: DC%2BD2M%2FmvF2ltQ%3D%3D
MA Bruno A Vanhaudenhuyse C Schnakers, et al. 2010 Visual fixation in the vegetative state: an observational case series PET study BMC Neurol 10 35 20504324 10.1186/1471-2377-10-35
RW Kentridge TC Nijboer CA Heywood 2008 Attended but unseen: visual attention is not sufficient for visual awareness Neuropsychologia 46 864 869 18237752 10.1016/j.neuropsychologia.2007.11.036 1:STN:280:DC%2BD1c7jtFejtA%3D%3D
M Tamietto F Cauda LL Corazzini, et al. 2009 Collicular vision guides nonconscious behavior J Cogn Neurosci 22 888 902 10.1162/jocn.2009.21225
DR Moreno ND Schiff J Giacino, et al. 2010 A network approach to assessing cognition in disorders of consciousness Neurology 75 1871 1878 10.1212/WNL.0b013e3181feb259
F Longoni M Grande V Hendrich, et al. 2005 An fMRI study on conceptual, grammatical, and morpho-phonological processing Brain Cogn 57 131 134 15708203 10.1016/j.bandc.2004.08.032
M Vigneau V Beaucousin PY Herve, et al. 2006 Meta-analyzing left hemisphere language areas: phonology, semantics, and sentence processing Neuroimage 30 1414 1432 16413796 10.1016/j.neuroimage.2005.11.002 1:STN:280:DC%2BD283lsV2htQ%3D%3D
MH Davis IS Johnsrude 2003 Hierarchical processing in spoken language comprehension J Neurosci 23 3423 3431 12716950 1:CAS:528:DC%2BD3sXjsFSkt7k%3D
G Hickok D Poeppel 2007 The cortical organization of speech processing Nat Rev Neurosci 8 393 402 17431404 10.1038/nrn2113 1:CAS:528: DC%2BD2sXksFSis7w%3D
A Riecker K Mathiak D Wildgruber, et al. 2005 fMRI reveals two distinct cerebral networks subserving speech motor control Neurology 64 700 706 15728295 10.1212/01.WNL.0000152156.90779.89 1:STN:280:DC%2BD2M%2FpvVyisQ%3D%3D
J Zhang EM Mitsis K Chu RE Newmark, et al. 2010 Statistical parametric mapping and cluster counting analysis of [18F] FDG-PET imaging in traumatic brain injury J Neurotrauma 27 1 35 49 19715400 10.1089/neu.2009.1049
JD Gabrieli RA Poldrack JE Desmond 1998 The role of left prefrontal cortex in language and memory Proc Natl Acad Sci USA. 95 906 913 9448258 10.1073/pnas.95.3.906 1:CAS:528:DyaK1cXosFSnsg%3D%3D
P Haggard 2008 Human volition: towards a neuroscience of will Nat Rev Neurosci 9 934 946 19020512 10.1038/nrn2497 1:CAS:528:DC%2BD1cXhtl2gsLfE
KY Haaland CL Elsinger AR Mayer, et al. 2004 Motor sequence complexity and performing hand produce differential patterns of hemispheric lateralization J Cogn Neurosci 16 621 636 15165352 10.1162/089892904323057344
G Gainotti 2001 Disorders of emotional behaviour J Neurol 248 743 749 11596777 10.1007/s004150170088 1:STN:280:DC%2BD3MrkvF2ksQ%3D%3D
MF Rushworth H Johansen-Berg SM Gobel, et al. 2003 The left parietal and premotor cortices: motor attention and selection Neuroimage 20 Suppl 1 S89 S100 14597301 10.1016/j.neuroimage.2003.09.011
MS Gazzaniga 2000 Cerebral specialization and interhemispheric communication: does the corpus callosum enable the human condition? Brain 123 Pt 7 1293 1326 10869045 10.1093/brain/123.7.1293
DJ Turk TF Heatherton CN Macrae, et al. 2003 Out of contact, out of mind: the distributed nature of the self Ann NY Acad Sci 1001 65 78 14625356 10.1196/annals.1279.005
AR Damasio 1998 Investigating the biology of consciousness Philos Trans R Soc Lond B Biol Sci 353 1879 1882 9854259 10.1098/rstb.1998.0339 1:STN:280:DyaK1M%2FntFChsQ%3D%3D
Edelman GM (2004) Wider than the sky: The phenomenal gift of consciousness. Yale University Press, New Haven and London
S Laureys F Perrin S Bredart 2007 Self-consciousness in non-communicative patients Conscious Cogn 16 722 741 17544299 10.1016/j.concog.2007.04.004 (discussion 742-745)
AK Seth Z Dienes A Cleeremans, et al. 2008 Measuring consciousness: relating behavioural and neurophysiological approaches Trends Cogn Sci 12 314 321 18606562 10.1016/j.tics.2008.04.008
S Majerus MA Bruno C Schnakers, et al. 2009 The problem of aphasia in the assessment of consciousness in brain-damaged patients Prog Brain Res 177 49 61 19818894 10.1016/S0079-6123(09)17705-1
MM Monti A Vanhaudenhuyse MR Coleman, et al. 2010 Willful modulation of brain activity in disorders of consciousness N. Engl J Med 362 7 579 589 20130250 10.1056/NEJMoa0905370 1:CAS:528:DC%2BC3cXisVegtLY%3D
M Boly MA Garrido O Gosseries, et al. 2011 Preserved feedforward but impaired top-down processes in the vegetative state Science 332 858 862 21566197 10.1126/science.1202043 1:CAS:528:DC%2BC3MXlslylsL0%3D