Scientists have shown that a patient in a persistent vegetative state can actually understand and “answer” questions. Use of functional Magnetic Resonance Imaging has shown very specific brain activity in response to questioning. Activity that can be interpreted in no other way than as a response to a question. This would tend to indicate that the patient in question still maintains higher brain functions. This type of persistent vegetative state is known as being “locked in” and appears to be the type of state that may eventually recover, although this has yet to be established.
This makes the arguments for euthanasia in comatose patients that much more difficult. It is clear from this interesting experiment that our understanding of the comatose state is very limited and that brain functions in comatose people may still be present. Certainly it is dangerous to argue that a person in a long-term coma is “just a shell” or the “living dead” as the Herald puts it.
This does not mean there is no valid ground for euthanasia of comatose patients, just that the justifications now move to the more subjective area of choice. “This is not what X would have wanted”, is still a possible argument, but “X is long dead” might not.
On the other hand, from a medical viewpoint, being able to run a more definitive test to see if brain function has truly completely ceased, may make those difficult, traumatic “ventilator” decisions a little easier. It would be good if we can put death into the “beyond reasonable doubt” category in these cases.