2007 Heart-Brain summit proceedings

Evaluating brain function
in patients with disorders
of consciousness

Facundo Manes, MD

Institute of Cognitive Neurology (INECO) Institute of Neuroscience,
Favaloro Foundation,
Buenos Aires, Argentina

fmanes@neurologiacognitiva.org

 

Tristan Bekinschtein, PhD

Institute of Cognitive Neurology (INECO),
Buenos Aires, Argentina
Impaired Consciousness Research Group,
University of Cambridge, Cambridge, UK

ABSTRACT

Evaluating brain function in patients with disorders of consciousness may offer important clues to their state of awareness and help to predict prognosis. Disorders of consciousness mainly comprise the comatose state, the vegetative state, and the minimally conscious state. These disorders typically stem from acute brain insults caused by hypoxic-ischemic neural injury or traumatic brain injury, and the type of brain injury frequently determines the neuropathology. Current knowledge, including results from our laboratory, supports a model of extended brain tissue damage from the midbrain to the cortex in anoxia patients and a model of focal or multifocal cortical lesions in trauma patients. These differing models may help to explain differences in prognosis and outcomes in these excruciating life situations. Although the neural basis of consciousness remains puzzling, findings from normal volunteers and pathologies of consciousness show that widely distributed networks such as thalamofrontal and parietofrontal systems may be critical.

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