* Is he dead? Doctors are telling me he is _brain_ dead, but his heart is beating…
* Doctors are telling me he will never regain consciousness, do they know for sure?
* In a coma sense me?
The _**palliative care team i**_s gently let you know that everybody will be better off if we pull the plug:
* The hospital cannot continue pouring money on this case
* Your wear and tear will be over
* It won't make any difference : He is dead to the world without possibility of communication, never mind recovery
_**So what is the medical knowledge about coma, vegetative states, and consciousness?**_
Well, Neuroimaging [1] has an article showing "..patients with little or no behavioral evidence of conscious awareness may retain critical cognitive capacities…Neuroimaging shows cognition in some patients without motor responsiveness…" The Journal of psychophysiology published a work [2] along similar lines.
The key here is the use of Functional Magnetic Resonance Imaging (fMRI). That technique consists in imaging the change in blood flow (hemodynamic response) related to energy use by neurons (Wikipedia} [3]
Below is a Wikipedia commons of an fMRI brain scan showing blood flow changes related to neuronal activity
[![][1]][2]
fMRI visualization of brain activity
_**So what is the definition of "brain dead".**_ A good article was published on how brain death is currently certified by doctors [4] . Most of the criteria seem to rely on the body's reaction to various stimuli and reflexes. After all , what else does the doctors have access to? Well, maybe neuroimaging of the type we just talked about could be useful, because it does not rely on the body's reaction, it is more of a direct proof of non activity. Remember [1] mentioned neuroimaging showed "cognition in some patients without motor responsiveness". Does "no motor responsiveness" include the lack of response of stimuli and reflexes of [4]? Not sure, but it seems that way.
Both studies mentioned in [5,6] agree, _neuroimaging has moved the frontier of conscious life _, and this has legal and ethical implications in palliative care.
Naturally, controversy has erupted: The interview by the German magazine Der Spiegel, of a Rom Houbin, a Belgian man , _while he was in coma_ could be bogus [7]
An excellent entry on current concepts in consciousness can be found in Scholarpedia [8]
_**Sources:**_
[1][ Neuroimage][3] ;"Coma and consciousness: Paradigms (re)framed by neuroimaging"
[2] [Journal of psychophysiology][4] ; "Functional Neuroimaging Approaches to the Changing Borders of Consciousness"
[3] [Wikipedia ; "Functional Magnetic Resonance Imaging"][5]
[4][ Indian Journal of Critical Care][6] ; "The diagnosis of brain death"
[5][ Progress in Brain Research][7]: "A new era of coma and consciousness science"
[6] [Nature Reviews Neurosciences; ][8] Functional neuroimaging in the vegetative state
[7] [Wired ; ][9]"Reborn Coma Man's Words May Be Bogus"
[8] [Scholarpedia][10] ; "Medical Ethics: Consciousness Levels and Palliative Care (Scholarpedia)"
[1]: http://www.medinewsdigest.com/wp-content/uploads/2011/12/fMRI-of-Brain.png (fMRI of Brain)
[2]: http://www.medinewsdigest.com/wp-content/uploads/2011/12/fMRI-of-Brain.png
[3]: http://www.sciencedirect.com/science/article/pii/S1053811911014431
[4]: http://www.sciencedirect.com/science/article/pii/S0269880310600311
[5]: http://en.wikipedia.org/wiki/Functional_magnetic_resonance_imaging
[6]: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2772257/
[7]: http://www.sciencedirect.com/science/article/pii/S0079612309177282
[8]: http://www.nature.com/nrn/journal/v9/n3/abs/nrn2330.html
[9]: http://www.wired.com/wiredscience/2009/11/houben-communication/
[10]: http://www.scholarpedia.org/article/Vegetative_state#Locked-in_syndrome
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