Sleep in Disorders of Consciousness

  • Victor Cologan
  • Manuel SchabusEmail author


From a behavioral as well as neurobiological point of view, sleep and consciousness are intimately connected. A better understanding of sleep cycles and sleep architecture of patients suffering from disorders of consciousness might therefore improve the clinical care for these patients as well as our understanding of the neural correlates of consciousness. Defining sleep in severely brain-injured patients is however problematic as both their electrophysiological and sleep patterns differ in many ways from healthy individuals. This work discusses the concepts used when studying sleep in patients suffering from disorders of consciousness and critically assesses the applicability of standard sleep criteria in these patients.

The available literature on comatose and vegetative (unresponsive wakefulness) states as well as that on locked-in and related states following traumatic or non-traumatic severe brain injury will be reviewed. A wide spectrum of sleep disturbances ranging from almost normal patterns to severe loss and architecture disorganization are reported with some sleep patterns being correlated to diagnosis or prognosis. At present the interactions of sleep and consciousness in brain-injured patients are little studied, yet highly interesting subject, which should receive more attention in the future.


Independent Component Analysis Sleep Pattern NREM Sleep Minimally Conscious State Sleep Spindle 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


  1. 1.
    Parthasarathy S, Tobin MJ. Sleep in the intensive care unit. Intensive Care Med. 2004;30(2):197–206.PubMedCrossRefGoogle Scholar
  2. 2.
    Rechtschaffen A, Kales A. A manual of standardized terminology, techniques and scoring system for sleep stages of human subjects. Bethesda: U.S. Department of Health, Education, and Welfare; 1968. p. 12.Google Scholar
  3. 3.
    Himanen SL, Hasan J. Limitations of Rechtschaffen and Kales. Sleep Med Rev. 2000;4(2):149–67.PubMedCrossRefGoogle Scholar
  4. 4.
    Mundigler G, et al. Impaired circadian rhythm of melatonin secretion in sedated critically ill patients with severe sepsis. Crit Care Med. 2002;30(3):536–40.PubMedCrossRefGoogle Scholar
  5. 5.
    Isono M, et al. Sleep cycle in patients in a state of permanent unconsciousness. Brain Inj. 2002;16(8):705–12.PubMedCrossRefGoogle Scholar
  6. 6.
    Pattoneri P, et al. Circadian blood pressure and heart rate changes in patients in a persistent vegetative state after traumatic brain injury. J Clin Hypertens (Greenwich). 2005;7(12):734–9.CrossRefGoogle Scholar
  7. 7.
    Fukudome Y, et al. Circadian blood pressure in patients in a persistent vegetative state. Am J Physiol. 1996;270(5 Pt 2):R1109–14.PubMedGoogle Scholar
  8. 8.
    Bekinschtein TA, et al. Circadian rhythms in the vegetative state. Brain Inj. 2009;23(11):915–9.PubMedCrossRefGoogle Scholar
  9. 9.
    Landsness E, et al. Electrophysiological correlates of behavioural changes in vigilance in vegetative state and minimally conscious state. Brain. 2011;134(8):2222–32.PubMedCrossRefGoogle Scholar
  10. 10.
    Bergamasco B, et al. The sleep cycle in coma: prognostic value. Electroencephalogr Clin Neurophysiol. 1968;25(1):87.PubMedGoogle Scholar
  11. 11.
    Chatrian GE, White Jr LE, Daly D. Electroencephalographic patterns resembling those of sleep in certain comatose states after injuries to the head. Electroencephalogr Clin Neurophysiol. 1963;15:272–80.PubMedCrossRefGoogle Scholar
  12. 12.
    Ron S, et al. Time-related changes in the distribution of sleep stages in brain injured patients. Electroencephalogr Clin Neurophysiol. 1980;48(4):432–41.PubMedCrossRefGoogle Scholar
  13. 13.
    Oksenberg A, et al. Phasic activities of rapid eye movement sleep in vegetative state patients. Sleep. 2001;24(6):703–6.PubMedGoogle Scholar
  14. 14.
    Brenner RP. The interpretation of the EEG in stupor and coma. Neurologist. 2005;11(5):271–84.PubMedCrossRefGoogle Scholar
  15. 15.
    Halasz P, et al. The nature of arousal in sleep. J Sleep Res. 2004;13(1):1–23.PubMedCrossRefGoogle Scholar
  16. 16.
    Freedman NS, et al. Abnormal sleep/wake cycles and the effect of environmental noise on sleep disruption in the intensive care unit. Am J Respir Crit Care Med. 2001;163(2):451–7.PubMedGoogle Scholar
  17. 17.
    Evans BM. What does brain damage tell us about the mechanisms of sleep? J R Soc Med. 2002;95(12):591–7.PubMedCrossRefGoogle Scholar
  18. 18.
    Britt Jr CW, Raso E, Gerson LP. Spindle coma, secondary to primary traumatic midbrain hemorrhage. Electroencephalogr Clin Neurophysiol. 1980;49(3–4):406–8.PubMedGoogle Scholar
  19. 19.
    Britt Jr CW. Nontraumatic “spindle coma”: clinical, EEG, and prognostic features. Neurology. 1981;31(4):393–7.PubMedCrossRefGoogle Scholar
  20. 20.
    Seet RC, Lim EC, Wilder-Smith EP. Spindle coma from acute midbrain infarction. Neurology. 2005;64(12):2159–60.PubMedCrossRefGoogle Scholar
  21. 21.
    Kaplan PW, et al. Clinical correlates and prognosis in early spindle coma. Clin Neurophysiol. 2000;111(4):584–90.PubMedCrossRefGoogle Scholar
  22. 22.
    Schabus M, et al. Hemodynamic cerebral correlates of sleep spindles during human non- REM sleep. Proc Natl Acad Sci USA. 2007;104(32):13164–9.PubMedCrossRefGoogle Scholar
  23. 23.
    Evans BM, Bartlett JR. Prediction of outcome in severe head injury based on recognition of sleep related activity in the polygraphic electroencephalogram. J Neurol Neurosurg Psychiatry. 1995;59(1):17–25.PubMedCrossRefGoogle Scholar
  24. 24.
    Valente M, et al. Sleep organization pattern as a prognostic marker at the subacute stage of post-traumatic coma. Clin Neurophysiol. 2002;113(11):1798–805.PubMedCrossRefGoogle Scholar
  25. 25.
    Schabus M, et al. Sleep spindle-related activity in the human EEG and its relation to general cognitive and learning abilities. Eur J Neurosci. 2006;23(7):1738–46.PubMedCrossRefGoogle Scholar
  26. 26.
    Bodizs R, et al. Prediction of general mental ability based on neural oscillation measures of sleep. J Sleep Res. 2005;14(3):285–92.PubMedCrossRefGoogle Scholar
  27. 27.
    Giubilei F, et al. Sleep abnormalities in traumatic apallic syndrome. J Neurol Neurosurg Psychiatry. 1995;58(4):484–6.PubMedCrossRefGoogle Scholar
  28. 28.
    D’Aleo G, et al. Sleep spindles in the initial stages of the vegetative state. Ital J Neurol Sci. 1994;15(7):347–51.PubMedCrossRefGoogle Scholar
  29. 29.
    D’Aleo G, et al. Sleep in the last remission stages of vegetative state of traumatic nature. Funct Neurol. 1994;9(4):189–92.PubMedGoogle Scholar
  30. 30.
    Oksenberg A, et al. Sleep-related erections in vegetative state patients. Sleep. 2000;23(7):953–7.PubMedGoogle Scholar
  31. 31.
    Gordon CR, Oksenberg A. Spontaneous nystagmus across the sleep-wake cycle in vegetative state patients. Electroencephalogr Clin Neurophysiol. 1993;86(2):132–7.PubMedCrossRefGoogle Scholar
  32. 32.
    George B, Landau-Ferey J. Twelve months’ follow-up by night sleep EEG after recovery from severe head trauma. Neurochirurgia (Stuttg). 1986;29(2):45–7.Google Scholar
  33. 33.
    Keshavan MS, Channabasavanna SM, Reddy GN. Post-traumatic psychiatric disturbances: patterns and predictors of outcome. Br J Psychiatry. 1981;138:157–60.PubMedCrossRefGoogle Scholar
  34. 34.
    Cohen M, et al. Temporally related changes of sleep complaints in traumatic brain injured patients. J Neurol Neurosurg Psychiatry. 1992;55(4):313–5.PubMedCrossRefGoogle Scholar
  35. 35.
    Clinchot DM, et al. Defining sleep disturbance after brain injury. Am J Phys Med Rehabil. 1998;77(4):291–5.PubMedCrossRefGoogle Scholar
  36. 36.
    Fichtenberg NL, et al. Insomnia in a post-acute brain injury sample. Brain Inj. 2002;16(3):197–206.PubMedCrossRefGoogle Scholar
  37. 37.
    Ouellet MC, Savard J, Morin CM. Insomnia following traumatic brain injury: a review. Neurorehabil Neural Repair. 2004;18(4):187–98.PubMedCrossRefGoogle Scholar
  38. 38.
    Guilleminault C, et al. Hypersomnia after head-neck trauma: a medicolegal dilemma. Neurology. 2000;54(3):653–9.PubMedCrossRefGoogle Scholar
  39. 39.
    Masel BE, et al. Excessive daytime sleepiness in adults with brain injuries. Arch Phys Med Rehabil. 2001;82(11):1526–32.PubMedCrossRefGoogle Scholar
  40. 40.
    Ouellet MC, Beaulieu-Bonneau S, Morin CM. Insomnia in patients with traumatic brain injury: frequency, characteristics, and risk factors. J Head Trauma Rehabil. 2006;21(3):199–212.PubMedCrossRefGoogle Scholar
  41. 41.
    Ouellet MC, Morin CM. Subjective and objective measures of insomnia in the context of ­traumatic brain injury: a preliminary study. Sleep Med. 2006;7(6):486–97.PubMedCrossRefGoogle Scholar
  42. 42.
    Ouellet MC, Morin CM. Cognitive behavioral therapy for insomnia associated with traumatic brain injury: a single-case study. Arch Phys Med Rehabil. 2004;85(8):1298–302.PubMedCrossRefGoogle Scholar
  43. 43.
    Hoedlmoser K, et al. Non-pharmacological alternatives for the treatment of insomnia—­instrumental EEG conditioning, a new alternative? In: Soriento YE, editor. Melatonin, sleep and insomnia. New York: Nova; 2011. p. 69–101.Google Scholar
  44. 44.
    Oksenberg A, et al. Polysomnography in locked-in syndrome. Electroencephalogr Clin Neurophysiol. 1991;78(4):314–7.PubMedCrossRefGoogle Scholar
  45. 45.
    Guilleminault C, Cathala JP, Castaigne P. Effects of 5-hydroxytryptophan on sleep of a patient with a brain-stem lesion. Electroencephalogr Clin Neurophysiol. 1973;34(2):177–84.PubMedCrossRefGoogle Scholar
  46. 46.
    Markand ON, Dyken ML. Sleep abnormalities in patients with brain stem lesions. Neurology. 1976;26(8):769–76.PubMedCrossRefGoogle Scholar
  47. 47.
    Cummings JL, Greenberg R. Sleep patterns in the “locked-in” syndrome. Electroencephalogr Clin Neurophysiol. 1977;43(2):270–1.PubMedCrossRefGoogle Scholar
  48. 48.
    Freemon FR, Salinas-Garcia RF, Ward JW. Sleep patterns in a patient with a brain stem infarction involving the raphe nucleus. Electroencephalogr Clin Neurophysiol. 1974;36(6):657–60.PubMedGoogle Scholar
  49. 49.
    Autret A, et al. A syndrome of REM and non-REM sleep reduction and lateral gaze paresis after medial tegmental pontine stroke. Computed tomographic scans and anatomical correlations in four patients. Arch Neurol. 1988;45(11):1236–42.PubMedCrossRefGoogle Scholar
  50. 50.
    Tamura K, et al. Disturbances of the sleep-waking cycle in patients with vascular brain stem lesions. Clin Electroencephalogr. 1983;14(1):35–46.PubMedGoogle Scholar
  51. 51.
    Lavie P, et al. Localized pontine lesion: nearly total absence of REM sleep. Neurology. 1984;34(1):118–20.PubMedCrossRefGoogle Scholar
  52. 52.
    Cologan V, et al. Sleep in disorders of consciousness. Sleep Med Rev. 2010;14:97–105.PubMedCrossRefGoogle Scholar

Copyright information

© Springer-Verlag London 2012

Authors and Affiliations

  1. 1.Coma Science Group, Cyclotron Research CenterUniversity of LiègeLiègeBelgium
  2. 2.Laboratory for Sleep and Consciousness Research, Department of PsychologyUniversity of SalzburgSalzburgAustria

Personalised recommendations