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It has been a while since I reported and commented on progress in understanding the minimally conscious state. Over recent months some exciting news reports have appeared which I feel it is appropriate to refer to here.

Firstly this article appeared in The Guardian last November about Rom Houben, a man who laid for 23 years, assumed to be in a Persistent Vegetative State (PVS), the state of being unaware of everything around you, oblivious to the world, when in fact he was hearing everything. A neurologist at the University of Liège (Dr Steven Laureys) examined him with new scanning technology and found that his brain seemed to be working quite normally. Most of the article continues to talk about an ability to communicate that was also thought to have been found, which it is now thought was a mistake, but a notable point comes toward the end of the write-up. The Guardian article quotes Dr Laureys, who is very experienced in these cases, as saying that of 44 patients he examined who were diagnosed as being in a vegetative state, 18 of them responded to communication. Furthermore, while it is not uncommon for patients with reduced levels of consciousness to have as little as one assessment by a professional which will determine their diagnosis, Steven Laureys said that such patients should be tested ten times, and that such states were like sleep, having varying stages which need to be monitored. This is an observation that I fully support from my experience with Ladan, there are times when Ladan is clearly out of it, there are times where there seems to be some very basic responsiveness to what is happening around her, often including to actual words being said, and then there are much less frequent occasions where for about 30 seconds or so she can interact with her eyes.  There is a clear difference even in Ladan’s appearance when she is in the most responsive state but it would be impossible to make a plan that would ensure  an expert examined her or scanned her during such an infrequent opportunity, even if she was tested ten times that moment would probably not be caught, but such a policy would probably suffice to catch Ladan at a time that she wasn’t at her least responsive. Luckily for Ladan she was found to have a degree of awareness on her second clinical neurological examination, but it could have taken more.   The more accredited professionals do generally maintain that there is no sure test that can prove an individual is not aware of what is happening around them, all the tools that science has can only help to make an educated guess and, more importantly, attempt to discover if somebody is suitable for a programme of rehabilitation. Unfortunately finding  some degree of awareness is not in itself sufficient for finding a rehabilitation method.

In this blog post a few years ago I referred to a study in Cambridge that, in the long term, may offer hope of rehabilitation techniques to the least able of minimally conscious patients, as well as uncover signs of consciousness in patients otherwise held to be in the persistent vegetative state.  I also looked at some of the potential dangers of misdiagnosis of PVS. That posting referred to a study by a team in Cambridge, including Dr Adrian Owen, in which a woman who was thought to be in a persistent vegetative state was asked to imagine playing tennis while she was scanned using a relatively new technique (fMRI) with an MRI scanner. The resulting changes in the  images on the scan were much the same as the changes witnessed in a fully conscious individual carrying out the same request.

At the beginning of February Channel 4 News ran a story about further research into this technique by teams led by both Dr Adrian Owen from Cambridge and Dr Steven Laureys from Liège.  Again taking a patient formerly thought to be in PVS, the same request of  imagining playing tennis was made to the patient but this time it was to be used  by the patient as a tool to indicate yes or no responses to questions.

“It works like this,” Dr Owen said, explaining the idea in this  Sunday Times article back in 2007, “Say you have a patient who responds positively, with proven volition, to the command ‘Imagine you’re playing tennis.’ You can then progress to an easy yes-no response.” [...] “To coin a phrase, it’s a no-brainer. If the answer to a question is yes, the patient thinks of playing tennis; if it’s no, the patient doesn’t think of playing tennis.”

Below is a news clip from Channel 4 News adding a little more detail about the successful experiment:

Where this technique is currently going to be most important is where it will make a difference to the long term plans for the patient. Here in North-East England the policy of medical and care staff is – as I understand it – to act on the assumption that even somebody thought to be in PVS may actually be aware and understanding everything around them, obviously there is no extra harm that will come from talking to somebody who can’t hear you, but it is not kind to completely ignore somebody who is fully aware of everything you are saying. Ladan is known to have some awareness and the nursing home she is in would, as a rule, treat her on that assumption even if she had been diagnosed as being completely unaware, but still I get disheartened when occasionally a carer will come into her room and assist with her needs without saying so much as a “hello” to her. I cannot imagine how much the frustration of being unable to communicate would be made worse for an individual diagnosed as being in a persistent vegetative state if it was acceptable to ignore them as a matter of policy because of their misdiagnosis. But beyond the doctors and carers there are – of course – the families, and a black and white misdiagnosis of PVS may make them even more likely to just stand and stare at a relative who would actually love to hear them talk to them. Dealing with trauma in a family is difficult enough as it is, if a family are informed through a misdiagnosis that their presence cannot possibly be known to their loved one, then the chances of the patient losing the support of their family must be greatly increased. It is important that families are not given assumptions of probability as fact, they have tough decisions to make ad should know the full picture, even if that picture is full of  ”probably not“s and “we don’t know“s, rather than definitive statements.

It should be noted that finding the ability to communicate with an individual formerly misdiagnosed as being in PVS is rare, even when some degree of awareness is found it is not usually a guarantee that they fully understand everything that is going on around them. It is possible that somebody who can communicate in a scanner may also not be fully aware of what condition they are in, though they may even falsely believe themselves to be, but what this offers, even at its most basic, is access to more facts upon which assumptions about a brain may be based. At its best it gives a patient a voice, though possibly not a say, in decisions over how they should be treated.

Looking into the future, these discoveries may help to provide rehabilitation techniques to those people in minimally conscious states who cannot react with the outside world in a consistent way. Current rehabilitation techniques need something to hook onto,  a consistent physical response, such as a finger that the patient will almost always move when requested. fMRI is still a relatively rare and very expensive facility, but it offers that ’something’ to hook onto in patients who have a reaction that shows up in the scanners imaging, and that means that either by using fMRI scanning regularly as part of a rehabilitation programme, or by finding other ways to detect the responses that using fMRI scanning has uncovered, the potential exists for a greater number of individuals who fall into a minimally conscious state to embark upon a programme of rehabilitation.
 
Links:

• The Guardian: Trapped in his own body for 23 years – the coma victim who screamed unheard
• Times Online: 40% of coma patients in a ‘vegetative state’ may be misdiagnosed, says a new report
• Channel 4 News: Paralysed patients communicate via brain scan