We have a patient in what is called a persistent vegetative state, that is to say more or less completely paralysed. Such a patient would have more or less normal wake-sleep cycles.
But how do we know if such a person is more than awake, whether he is conscious or not?
A group of scanner scientists have found a way to talk, after a fashion, with some such people. The idea is that you put the patient in the scanner. The instruction to the patient is that he answers yes to a question by thinking about playing tennis and that he answers no by thinking about walking around his house.
Sometimes the signals picked up by the fMRI scanner from these thoughts can be reliably decoded into ‘yes’ and ‘no’, thus enabling a conversation of sorts. And, following the jargon of IT security consultants, there is talk from these consciousness consultants of covert channels of communications, with the trick with the fMRI scanner being very much the sort of thing which makes up the stock in trade of the security boys. Another group has extended the repertoire to thinking in 27 different ways, 27 different ways which can sometimes be decoded by the scanner as the 26 letters of the alphabet plus space. A bit laborious and nothing like as reliable as tennis versus house, but maybe a technique with a future. And yet another group has achieved similar results using bedside EEG equipment, far cheaper and more convenient than moving patients into fMRI scanners.
This particular patient, when awake, can hear if not see what is going on around him. He has subjective experience and he can direct his thoughts. He has choice in that he can, for example, choose whether to think about tennis rather than football. He also has memory. Enough working memory to process inbound language. Enough to remember and obey instructions. The authors of reference 1 also devised experiments to demonstrate the formation of longer term memories and the understanding of concepts like pain.
The authors argue that being able to communicate in this way is good evidence, to the point of no-contest, of more or less normal consciousness. While to my mind, what has been done is suggestive of consciousness, but not conclusive. Certainly not no-contest.
I start my ruminations by observing a moment of respect.
This patient is, or at least was, a person and the deconstruction of his mind is a tearing aside of the veil, is a public sign of disrespect. One might object, in rather the same way as one does not care for the autopsies of one’s loved ones, necessary or useful though they may be. But at least autopsies take place more or less in private and are carried out by people who are a caste apart. I associate to the thought that the much-derided caste system does have its points.
Some generalities
I start by running past various aspects of the twin issues of conscious or not and the nature or quality of this consciousness.
One. My starting point is the well attested fact that we often do complicated things of which we are not conscious. One might, for example, drive to work in the morning while thinking about the meeting to come and arrive at work with no memory whatsoever of the journey – but with the conduct of the meeting all sorted out. In which case, one might argue that the driving had been unconscious. And there are plenty of sports people who talk about the need to empty the mind and let the body take over: consciousness gets in way of world class performance. And a champion rock climber who talked about how it all flowed when things were going well: an intense experience of a world reduced to and fused from the self, the rock and the climb.
Two. I then turn to the question of whether consciousness is for anything, or whether it is just a bit of froth on the surface of things which does not have any bearing on what is going on inside, on behaviour. A product of behaviour rather than a cause. With epiphenomenon being the proper word for froth. And if consciousness is one of these, an epiphenomenon, then there is the possibility, in brain damaged circumstances, that consciousness and behaviour could become detached in a way in which they do not in normal life.
Lesson: we need to be careful about inferring consciousness from complex behaviour.
Three. Next up is brain death, which a quick peek at Wikipedia tells me is something which is sometimes held to exclude the brain stem machinery which is needed to keep things ticking over – ticking over which includes breathing. Machinery which in the present case is clearly still working. Furthermore, this brain is clearly exhibiting plenty of activity, in response to instructions, activity which correlates well with that of the rest of us. Lots of life, certainly not dead.
Lesson: remember that the trick with the scanner only works with some of those in a vegetative state. Brain life is not the same as even rudimentary consciousness.
Four. When we are asleep, my understanding is that most of the motor machinery in the brain is disconnected from the corresponding motor machinery in the body, certainly the arms and legs, which means we do not flail about when we are asleep – although there must be enough left so that we can turn over from time to time and so avoid bed sores. I wonder whether, when we are asleep and dreaming about playing tennis, an fMRI scan would reveal the same patterns as are discussed in reference 1? In the case of our patient, given that the damage was done to his head rather than his body, I suppose that some part of the motor machinery in the brain has been damaged, to the point of disconnecting the brain from the arms and legs, but not to the point of suppressing the motor flavoured patterns.
Lesson: there is plenty of work that could be done at the margins, patients and funding permitting.
Five. Then there is the rise of the robots, which are getting so clever now that some people (quite rightly) worry about what sort of beings we are bringing into life. Are these robots alive in any sense of the word? Are they conscious? Do they have rights? However, at the moment, I do not think that any such machines have the sort of inner life that might be detected by a scanner. Scanners are designed to detect electrical activity of a different order from that in a computer, even supposing we could get at that of a computer, from the outside. On the other hand, it does not seem so far fetched that we have a robot in a heap on the floor, to all in purposes finished. But then we plug into its USB port, peer at the innards of our robot and work out what parts of its motor machinery were working and what parts needed to be fixed, work some magic with our laptop and, lo and behold, the robot springs back into life, with its memory of its past life intact. It just picks up where it left off. And noting here that there is nothing tricky about giving a robot memory: one just logs what it sees and what it does. Maybe build a few indexes. So at one level, our robot in a heap shares features and behaviour with someone in a coma. But at another, no-one yet is claiming any sort of consciousness, any sort of subjective experience for it. It does not have any rights.
Lesson: I think emerging definitions of conscious, emerging tests for consciousness of humans, should be applied to machines: does such application give us the result we want or expect? Not because we are interested (here anyway) in the condition of the machines, rather because it helps to refine out tests.
Six. Tools like the Glasgow Coma Scale are widely used in the assessment of the critically ill, particularly those who have had strokes and those who have had other head injuries. A multivariate score built on three variables: eye opening, verbal response and motor response – but see reference 4 for more details. My guess is that this particular patient would have had very low scores on this scale – which low scores have a strong association to a poor outcome. While a concern that patients with low scores may have a richer inner life than this might suggest is very much part of the rationale for doing work of the present sort.
Lesson: a low score on the GCS is not the whole story.
Some particulars
Our man in a scanner can only report of his state of mind in a very rudimentary way. I now move onto various more easily reported disturbances of consciousness, with the idea of putting the foregoing into a wider context.
Stroke one
Stroke one is prompted by going to a performance of ‘Wings’, a play about recovering from a stroke by Arthur Kopit and starring, on this occasion, Juliet Stevenson. I leave aside the business of recovering speech and other motor skills.
A play which left me with the idea that in the wake of a stroke, what one knows in life as an integrated and continuous consciousness of oneself, one’s actions and one’s surroundings, can become fragmented.
One can hear oneself saying stuff when one is not talking out loud, so that other people do not get to hear what one is saying at all.
One can say stuff to other people which one does not hear oneself.
One’s hand can start to do stuff which one has not told it to do. The hand is then seen, as it were, as something alien to oneself. From where I associate to the famous experiments with the pink rubber hand, introduced at reference 7.
In rather a similar way, one can hear stuff going on in one’s head for which one feels no sense of ownership or responsibility. Or one can hear oneself saying stuff for which one feels no sense of ownership or responsibility. I associate to a story of a epileptic fit, which the subject both was conscious of and remembered (noting in passing that being conscious of something that you do not remember is a tricky business) and during which he lost all control of the activities of his arms and legs, which were flailing about without any reference to higher command.
There was also the idea that one could have the concept of something, say the ceiling, without being able to put a word to it. The indexing functions are still working, all the right bits of the brain have been activated and nearly all the right stuff is coming up. It is just the word bit which we cannot bring to mind, cannot articulate. One might go so far as to argue that it is not the word that one has lost, just the instructions on how to say it. Something which sometimes happens without the benefit of a stroke.
The lady in question had been to do with small aeroplanes and wing walking as a young person and there was lots of rather acrobatic floating. I suppose that this was all about having the sensation of floating around, while actually lying in bed. There was also an out of body experience, looking down on her own body. Experiences which I believe are fairly well attested. After all, a computer would have no trouble presenting to its screen an unusual view of an object that it knew about, such as itself.
Stroke two
Stroke two comes from Simenon’s novel about recovering from a stroke, first noticed at reference 3 and illustrated above.
A novel which starts with the narrator coming round after a stroke, a coming round which is not that different from waking up. But after a while he finds that he cannot move or talk, or even open his eyes. Which is frightening, but there was also a sense that he could just lie back and let it all flow. Just lie quiet and be content with his inner world.
There is also a reference back to the ceiling of stroke one, in that the narrator, some days later, heard a distinctive, a familiar sound – in fact the creaking of a wooden chair – but cannot put a name to it. Contrariwise, unlike the victim of stroke one, he cannot be bothered to try a bit harder.
As he comes round a bit more, he is fortunate to have people around him making reassuring noises, telling him reassuring things. And, indeed, as it turns out, he recovers fairly quickly, the steady progression of which must go a long way towards dissipating fear and anxiety. Something which is not going to be available to someone locked in. There will be no progression, even if there is no thought that there will be none either.
The business of not being bothered persists, and he continues to wonder why everybody is rushing around so much, why he was rushing around in just the same way until just a very few days previous. He was quite content just to lie quietly in his more or less private world, doing nothing and troubling about nothing. Again, not the same story at all as the victim of stroke one.
But as he got better, from a serene indifference to the silly affairs of the world, he gradually moved to being irritated by them. And shortly after that he resumed his participation in it.
In any event, on this telling, and I believe that Simenon did do his homework, albeit more than fifty years ago, apart from there being a gap in the narrator’s memory between having the stroke and it taking a while before all the various services one expects from one’s brain came back online, the narrator got more or less better within a few weeks. All quite upbeat – but then the narrator had the best, as no doubt Simenon would have had, had need ever arisen.
However, while one does get better, things are not the same as they were. One has been to a place where one sees things from a different perspective and, at the risk of sounding pious or social worker, I think one is a better person for it.
Substances
Mind altering substances. Drink changes mood and it may change the shape of things to come, but, in moderation, does not change the fabric of consciousness. While morphine at pain killing doses does. At least, in the two cases that I can remember, things did not get psychedelic after the fashion of posters and such like in the 1970’s, but they did get rather jumbled up. And irritating, unlike in my dreams where the jumbling up is barely perceived and in any case tolerated. Nothing like the states portrayed in stroke one.
While Huxley famously reports on greater length with his experiences of mescaline – as I recall, an experience he attempted to repeat as he died of lung cancer, at the moment of his death. The story was that he was very impressed by how vivid the visual experience was, untainted, he thought, by all the manipulations of the ego and super-ego. For once you saw things how they were in the raw. Not like drink at all, with my own experience of being drunk being that one’s emotions become all of vivid, fleeting and fragile; labile even. While one’s images of people and things are apt to be built on the basis of those emotions, good or bad. The good will be very good, and the bad very bad, but in any event very much a construct of the mind, be that id, ego or superego, as much as that of the eyes. I settle for UCS.
Fevers
Having recently had half a day of slight fever, I can report that my state of mind was somewhere between morphine induced day-dreaming and the altered consciousness as reported by Huxley.
Things that I try to visualise while lying in bed with eyes shut were much more vivid than they are normally. So playing the triangle game mentioned at the end of reference 5 is much more lively.
I also experienced, in a small way, the withdrawal from the world of stroke two. For a while I was quite content to burrow in the bedclothes, think my own thoughts and let the rest of the world go hang. The idea of getting out to eat was most unattractive.
On the other hand, thinking in words was sometimes very muddled, rather as it was with morphine induced day-dreaming. But again, not so muddled that one did not know it was muddled and with the muddled thinking being apt to vanish when one tried to approach it more closely.
Trauma
It so happens that I have been taking another look at ‘Façades’, first noticed at reference 8, and on page 477 in the chapter headed ‘Something macabre out of Proust’, there is a short description of the effect that a bad, head smashing fall had on Osbert Sitwell’s friend David:
‘But David did survive … gradually the coma lifted … his battered brain reversed the meanings of words so that he spoke in contraries, saying ‘yes’ when he meant ‘no’ … painfully beginning to walk again – and learning to write left handed … before the accident he had been virtually bilingual in French and English. Now he could not speak a word of French…’
Nicely encapsulating the various effects on the workings of the brain which might result from trauma.
One would only have liked a little more on the business of contraries. Did David know it was the wrong word, with just his speech apparatus getting in a muddle, or did he think it was the right word?
Waking thoughts
And lastly, while waking one recent morning, my thoughts turned to being locked in while waking up, this while lying in bed, in the dark, with my eyes shut.
Plenty of action in the brain, some action in the body and some sensations from the body. Some sounds from the house and the world outside. Some choices in that I could, for example, choose whether to wriggle my toes or not, giving rise to the thought that it would be rather odd, not to say frightening, if there was no possibility of motor action at all.
Although such paralysis does not usually extend to the chest, one is still breathing. Why do the muscles that do that get let off? A thought which resulted in a later excursion to Bing and Wikipedia.
Other choices in that I could, to some extent, choose what to think about. At least, the unconscious could offer various possibilities, from which I would, successfully, pick one. Giving rise to the thought that it would be rather odd, not to say frightening, if thoughts were coming into mind, unbidden, as it were. And when one can move about, one can usually put such unwanted thoughts out of mind, one can create effective diversions, which might be more difficult if one could not move about.
But all that aside, no doubt at all in my mind that I was more or less fully conscious.
That said, I also believe in degrees of consciousness. Being conscious or not may seem, to a normal, healthy person not much concerned with these matters, to be, more or less, an on-off thing, and certainly that is my own (limited) experience of general anaesthetics. But sometimes one is aware of a transition when going to sleep and more often when waking up. The closing down and booting up of all the various services mentioned above.
From where, for some reason, I associate to the idea the bodily equipment which is not used is apt to wither away. So muscles fade to the point where one has to start over with walking. While the alimentary tract might fade past the point of no return. So waking up, after some months or years out of the game, might not be so hot.
And then at little later, I read in today’s Guardian that here in the UK, while we remain stuck on not allowing assisted dying (while a large chunk of the rest of the western world has moved on), we do allow tube feeding and watering to be withdrawn from a person who is deemed to be minimally conscious but otherwise beyond cure. We will get there in the end.
Further thoughts
It is very clear that one can be conscious while lying quiet and still in a state of sensory deprivation. It is very clear that one can be conscious, in the everyday sense of the word, even when one is badly damaged.
But it also seems to be the case that consciousness comes in many varieties, with not all that variation being down to what it is that one is conscious of or to the context. Some of the variation will be accounted for by variation from person to person and some of it will be accounted for by changes to people over time, changes which include growth, development, abuse, damage, disease and decay. Noting that after abuse, damage or disease, one cannot be sure that either the mind or the body will make a full recovery.
That said, on the LWS-N hypothesis on the generation of consciousness from the activation of a small patch of cortex, it seems likely that one could devise a measure, a single non-negative real number, which would tell one whether or not this state of LWS-N was a conscious state. A measure which depends on just the LWS-N itself and nothing else, nothing else from the wider brain in which it is to be found. Generally speaking, its value would tend to be near zero (for unconscious) or to be near one (for conscious), but we do admit other values and our choice of boundaries is going to be a little arbitrary – this last being one of the criticisms of the GCS, although it is hard to see how such choice are going to be avoided.
On the other hand, the compiler, the compiled data and the activation processes are all complex objects, complex processes. It seems quite plausible that odd things could go wrong with its parts which do not destroy the whole, but which do make the resulting subjective experience odd or troubling. Or perhaps it is rather like genes: most random damage, most random changes result in a non-viable genome; it is only the chosen few that make it to birth.
Conclusions
We are still some way from having a good, measurable definition of consciousness. We are not helped in this by consciousness usually including, involving or just coming with all kinds of cerebral services which, in times of trouble or stress, can be modified, degraded or which can come and go on an individual basis. It is not all or nothing and there are plenty of shades of grey. We are even further from having a good, measurable definition which can be used on the front line, for example, in A&E units or by ambulancemen.
Nevertheless, having chewed around for a bit, I come to agree with the authors of reference 1. While one might argue about the quality or extent of the consciousness involved, a person who can talk to an fMRI scanner in the way described should be deemed to be conscious and should be accorded the same courtesies as any other conscious person, certainly in so far as this is practical or reasonable. But courtesies which might extend to letting them die in peace.
PS: the use of the phrase ‘coming with’ in the first paragraph of this section was significant, deliberate. With LWS-N, I am mostly concerned with the business of projecting content into consciousness, as can be seen at reference 5. In which, all these aforementioned services might go towards providing content, but they do not go towards actually making that content conscious.
References
Reference 1: Detecting awareness after severe brain injury - Davinia Fernández-Espejo and Adrian M. Owen – 2013.
Reference 2: How science found a way to help coma patients communicate – Owen – Guardian – 5th September 2017. The article which led me to reference 1.
Reference 3: http://pumpkinstrokemarrow.blogspot.co.uk/search?q=passouline.
Reference 4: http://www.glasgowcomascale.org/.
Reference 5: http://psmv3.blogspot.co.uk/2017/09/geometry-and-activation-in-world-of.html.
Reference 6: The Doors of Perception - Aldous Huxley – 1954.
Reference 7: https://en.wikipedia.org/wiki/Body_transfer_illusion.
Reference 8: http://psmv3.blogspot.co.uk/2017/08/facades.html.
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