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Detecting awareness after severe brain injury


Recent developments in functional neuroimaging have provided a number of new tools for assessing patients who clinically appear to be in a vegetative state. These techniques have been able to reveal awareness and even allow rudimentary communication in some patients who remain entirely behaviourally non-responsive. The implications of these results extend well beyond the immediate clinical and scientific findings to influencing legal proceedings, raising new ethical questions about the withdrawal of nutrition and hydration and providing new options for patients and families in that decision-making process. The findings have also motivated significant public discourse about the role of neuroscience research in society.

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Figure 1: Electroencephalography activity demonstrating command-following and awareness in a patient diagnosed as being in a vegetative state for 12 years.
Figure 2: Functional MRI-based communication in a patient diagnosed as being in a vegetative state for 12 years.


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We thank G. B. Young and D. Cruse for their expert advice and assistance regarding the patient described in detail in this Perspective. This work was funded by awards to A.M.O. from the Canada Excellence Research Chair (CERC) Programme, the Canadian Institutes of Health Research (CIHR) and the Natural Sciences and Engineering Research Council of Canada (NSERC).

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Correspondence to Davinia Fernández-Espejo or Adrian M. Owen.

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The authors declare no competing financial interests.

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Structural imaging in the vegetative and minimally conscious states (PDF 211 kb)

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Fernández-Espejo, D., Owen, A. Detecting awareness after severe brain injury. Nat Rev Neurosci 14, 801–809 (2013).

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