There’s an interesting and in-depth article in The New Yorker on using brain scans to communicate with people who may be trapped in a persistent vegetative state (PVS) – a coma-like condition that can occur after severe brain injury.
The article focuses on the work of Dr Adrian Owen and colleagues who published a key paper [pdf] in Science last year which reported changes in voluntary brain activation in response to verbal request in a patient who was seemingly unconscious when assessed externally.
The research suggests that some of these patients may be misdiagnosed as being unconscious, when, in fact, they are aware of their surroundings but trapped in their immobile bodies.
Needless to say the research has both stirred some primal fears and garnered a great deal of scientific interest.
Recent research by Owen and other neuroscientists may eventually help make diagnoses more accurate, but it is not yet clear how the new brain-scan data will affect the medical understanding of consciousness. As Owen put it, “The thought of coma, vegetative state, and other disorders of consciousness troubles us all, because it awakens the old terror of being buried alive. Can any of these patients think, feel, or understand those around them? And, if so, what does this tell us about the nature of consciousness itself?”
The article goes on to consider what implications this study has for our understanding of consciousness and discusses some other fascinating studies which suggest how disordered brains can give leads into this crucial question.
One important application of this understanding is to work out ways to ‘awaken’ patients in similar states, which includes using implanted brain electrodes to stimulate under-active arousal-related brain areas.
I found the article via Frontal Cortex, which also has some interesting speculation on the possible links between these states and ‘blindsight’.
Link to New Yorker article ‘Silent Mind’.
Link to information on persistent vegetative state.