Uncovering Consciousness in Unresponsive ICU Patients: Technical, Medical and Ethical Considerations

  • B. Rohaut
  • A. Eliseyev
  • J. ClaassenEmail author
Part of the Annual Update in Intensive Care and Emergency Medicine book series (AUICEM)


Over a decade ago, researchers published the first case of a patient who had been clinically unresponsive for years after traumatic brain injury (TBI) and demonstrated command following using motor imagery paradigms visualized by functional magnetic resonance imaging (fMRI) [1]. The term “cognitive motor dissociation” is gaining popularity to describe this scenario of an inability to behaviorally express preserved cognitive processes [2]. Alternative labels are covert or hidden consciousness and functional locked-in syndrome [3] (see Table 34.1). A flurry of subsequent studies using fMRI and functional electroencephalogram (fEEG) approaches explored the boundaries of human consciousness following brain injury. This growing body of knowledge is now being discussed in the lay press and is starting to affect clinical medicine, challenging the classical taxonomy of disorders of consciousness ([4] see Table 34.1). Until very recently, researchers have focused their attention on patients suffering from chronic disorders of consciousness and have generated estimates of cognitive motor dissociation of around 15% using convenience samples of these patients [5]. Detection of cognitive motor dissociation in the acute phase of brain injury may have prognostic significance as these patients are more likely to also recover behavioral command following and have better long-term functional outcomes.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Neurocritical Care, Department of NeurologyColumbia UniversityNew YorkUSA

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