Medical Communication with woman in persistent vegetative state

[Ivan Seeking]

...FMRI (functional magnetic resonance imaging) was used to record brain activity in the woman five months after her accident. Doctors had diagnosed her as being in a persistent vegetative state.

...Dr. Owen added, "It tells us the patient could understand speech, because of course, we asked her to do these things. It also tells us that she is able to perform simple tasks in her head, such as imagining certain scenarios. We see this as a proof of principle: we have found a way to show that a patient is aware when existing clinical methods have been unable to provide that information."

http://www.medicalnewstoday.com/medicalnews.php?newsid=51473

 

[Kurdt]

This study was exceptionally interesting and I think forces us to rethink our philosophy on the whole issue. I suppose now one could 'ask' the patient what they would prefer.

 

[franznietzsche]

This study was exceptionally interesting and I think forces us to rethink our philosophy on the whole issue. I suppose now one could 'ask' the patient what they would prefer.

You could ask a serious of factual yes or no questions to the patient, and map the scan results to the expected answers. With a large enough number of samples, you could achieve such basic communication. Hypothetically, of course.

 

[zoobyshoe]

My first question is whether or not she is actually in a chronic vegetative state or something that merely mimics one, like the condition of the patients presented in Oliver Sack's Awakenings. They were all thought to be completely unconscious of the environment until the administration of L-dopa allowed them to move and speak again, whereupon it was discovered they always had complete awareness of the environment - they were simply unable to respond to it.

Sacks first suspected they might have some level of consciousness because of a similar, but cruder, brain "scan": the EEG. He saw a sudden spike in an otherwise flat EEG when he happened to speak the patient's name.

 

[MeJennifer]

I have trouble with the title though:

"Detecting Awareness in the Vegetative State"

Just telling a person in vegetative state to play tennis and then finding a comparison with the brain patterns of healthy volunteers who play tennis is no indication that the person is actually aware of such activities.

 

[Kurdt]

Well whatever the situation I take it they're not going to stop at merely one sample patient.

 

[franznietzsche]

I have trouble with the title though:

"Detecting Awareness in the Vegetative State"

Just telling a person in vegetative state to play tennis and then finding a comparison with the brain patterns of healthy volunteers who play tennis is no indication that the person is actually aware of such activities.

But the person responding on cue to verbal commands in a mental way indicates some level of awareness. Not necessarily complete awareness.

 

[MeJennifer]

Well whatever the situation I take it they're not going to stop at merely one sample patient.

No and I suppose it won't stop with scientific research as well, I presume this is interesting material for those who interrogate professionally as well.

Perhaps in the future not just our luggage will be scanned at airport security

 

[franznietzsche]

No and I suppose it won't stop with scientific research as well, I presume this is interesting material for those who interrogate professionally as well.

Perhaps in the future not just our luggage will be scanned at airport security

I assume you've heard of lie detectors, right?

 

[Kurdt]

I can imagine the check in times if that were to happen.

 

[zoobyshoe]

No and I suppose it won't stop with scientific research as well, I presume this is interesting material for those who interrogate professionally as well.

Perhaps in the future not just our luggage will be scanned at airport security

Yeah, it would be a nightmare if the government decided this was the basis for a means of reading people's thoughts.

 

[PIT2]

This one is also interesting: a sleeping pill that awakens comatose patients:

Louis is given a pill, and I watch. It is 8.30am. After nine minutes the grey pallor disappears and his face flushes. He starts smiling and laughing. After 10 minutes he begins asking questions. His speech is impaired because of the brain damage and the need, several years ago, to remove all his teeth, but I can understand him. A couple of minutes later, his right arm becomes less contorted and the facial drooping lessens. After 15 minutes he reaches out to hug Sienie. He pulls off her wedding ring and asks what it is. "It's a suffer-ring," she jokes. And he says, "Well, if you're suffering, you should make a plan!" The banter continues and he remembers conversations from the previous day and adds to them.

"Louis," I ask, "do you feel any change in awareness before and after the pill?" "No," he says. "None whatsoever." Whatever is happening, he feels the same. "How do you know this is your mother?" I ask, referring to Sienie. Remember, Louis cannot see. He says: "Because I recognise her voice and I know she loves me."

...

After Louis' awakening was publicised in the South African media, Dr Ralf Clauss, a physician of nuclear medicine - the use of radioactive isotopes in diagnostic scans - at the Medical University of Southern Africa, contacted Nel to suggest carrying out a scan on Louis. "The results were so unbelievable that I got other colleagues to check my findings," says Clauss, who now works at the Royal Surrey County Hospital in Guildford. "We did scans before and after we gave Louis zolpidem. Areas that appeared black and dead beforehand began to light up with activity afterwards. I was dumbfounded - and I still am."

...

"The results so far could be potentially very important," says Meyer. "We have never before spoken of damaged cells in the brain going into hibernation - we have thought of them as necrotic, or dead, cells. But we know cells can go into hibernation in the heart and thyroid, so why not the brain? If there are hibernating cells in damaged brains, it may be that this drug helps to wake them in some people."

http://www.guardian.co.uk/medicine/story/0,,1870279,00.html

 

[zoobyshoe]

That's an interesting article, Pit.

No one yet knows exactly how a sleeping pill could wake up the seemingly dead brain cells, but Nel and Clauss have a hypothesis. After the brain has suffered severe trauma, a chemical known as Gaba (gamma amino butyric acid) closes down brain functions in order to conserve energy and help cells survive. However, in such a long-term dormant state, the receptors in the brain cells that respond to Gaba become hypersensitive, and as Gaba is a depressant, it causes a persistent vegetative state.

It is thought that during this process the receptors are in some way changed or deformed so that they respond to zolpidem differently from normal receptors, thus breaking the hold of Gaba. This could mean that instead of sending patients to sleep as usual, it makes dormant areas of the brain function again and some comatose patients wake up.

In other words, they propose the pill works because much of the unconsciousness is a kind of post traumatic survival mechanism rather than the direct result of damage.

 

[PIT2]

In other words, they propose the pill works because much of the unconsciousness is a kind of post traumatic survival mechanism rather than the direct result of damage.

What about this part:

"Louis," I ask, "do you feel any change in awareness before and after the pill?" "No," he says. "None whatsoever." Whatever is happening, he feels the same. "How do you know this is your mother?" I ask, referring to Sienie. Remember, Louis cannot see. He says: "Because I recognise her voice and I know she loves me."

I thought this was confusing, does it mean that he was conscious before taking the pill?

 

[zoobyshoe]

I thought this was confusing, does it mean that he was conscious before taking the pill?

I found that confusing, also.

 

[hypnagogue]

I haven't read the paper, but this strikes me as an interesting result that should nonetheless be approached with some skepticism. For instance, it may be possible that the brain activity present in both the PVS patient and the healthy controls can occur without conscious awareness. To draw strong conclusions from this study we would need to show that the observed pattern of brain activity is sufficient for conscious imagery to occur. Along these lines, it would be interesting to see if similar patterns of brain activity could be elicited from the same stimulus in subjects whom we would suspect would actually not be aware of any corresponding imagery-- e.g. for sleeping subjects, or subjects who are instructed beforehand to try to suppress any visual imagery after hearing the command.

 

[zoobyshoe]

I haven't read the paper, but this strikes me as an interesting result that should nonetheless be approached with some skepticism. For instance, it may be possible that the brain activity present in both the PVS patient and the healthy controls can occur without conscious awareness. To draw strong conclusions from this study we would need to show that the observed pattern of brain activity is sufficient for conscious imagery to occur. Along these lines, it would be interesting to see if similar patterns of brain activity could be elicited from the same stimulus in subjects whom we would suspect would actually not be aware of any corresponding imagery-- e.g. for sleeping subjects, or subjects who are instructed beforehand to try to suppress any visual imagery after hearing the command.

I think you're right: the fact the PV person's response seems to have been triggered by the outside stimulus is no guarrantee that the patient himself is conscious of the stimulus and his own reaction.