Semin Neurol 2022; 42(03): 283-298
DOI: 10.1055/a-1893-2785
Review Article

Sleep and Circadian Disturbance in Disorders of Consciousness: Current Methods and the Way towards Clinical Implementation

Glenn J. M. Van der Lande
1   Centre du Cerveau2, University Hospital of Liège, Liège, Belgium
4   Coma Science Group, GIGA-Consciousness, University of Liège, Liège, Belgium
Christine Blume
2   Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, Switzerland
3   Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland
Jitka Annen
1   Centre du Cerveau2, University Hospital of Liège, Liège, Belgium
4   Coma Science Group, GIGA-Consciousness, University of Liège, Liège, Belgium
› Author Affiliations
Supported by: Belgian Federal Science Policy Office - PRODEX Programme
Supported by: Center-TBI FP7-HEALTH- 602150
Supported by: European Commission
Supported by: European Space Agency FNRS PDR
Supported by: European Space Agency T.0134.21
Supported by: Fondazione Europea Ricerca Biomedica
Supported by: Fonds De La Recherche Scientifique - FNRS
Supported by: Fonds Léon Fredericq
Supported by: Freiwillige Akademische Gesellschaft
Supported by: Fundação Bial
Supported by: European Commission
Supported by: Horizon 2020 Framework Programme EU-H2020-MSCA–RISE–778234
Supported by: Specific Grant Agreement No. 945539 (Human Brain Project SGA3)
Supported by: Koning Boudewijnstichting
Supported by: Mind-Care foundation
Supported by: Mind Science Foundation
Supported by: Novartis Stiftung für Medizinisch-Biologische Forschung
Supported by: Psychiatric Hospital of the University of Basel (UPK)
Supported by: Public Utility Foundation “Université Européenne du Travail”
Supported by: Research Fund for Junior Researchers of the University of Basel
Supported by: Télévie Foundation


The investigation of sleep in disorders of consciousness (DoC) has shown promising diagnostic and prognostic results. However, the methods employed in this field of research are diverse. This leads to confusion in the way forward for both scientific and clinical purposes. We review the literature that has investigated sleep in DoC patients and specifically outline the methodologies used next to the presented results. We highlight what knowledge we currently have and where increased efforts are needed before further clinical implementation. Specifically, the review shows that successful methods may employ a two-stage approach to sleep scoring, where one is the application of loosened standard criteria and the other a more general factor describing closeness of the electroencephalography to a healthy pattern, including a score that describes the extent to which sleep scoring criteria can be applied. This should be performed as part of a multimodal approach that also includes investigations of eye-opening/closure and that of circadian (24-hour) rhythmicity. Taken together, this puts the most promising methodologies in the field together for a comprehensive investigation. Large-scale approaches, incorporating multiple modalities and looking at individual variation, are now needed to advance our understanding of sleep in DoC and its role in diagnosis, treatment, and recovery.

Publication History

Accepted Manuscript online:
06 July 2022

Article published online:
13 September 2022

© 2022. Thieme. All rights reserved.

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