Locked in

I have spent part of today reading about communicating with people who are locked in, that is to say people who are presumed to be conscious and to be aware of their surroundings when awake, but who are completely paralysed and cannot even communicate by flicking an eyelid or twitching the mouth, with the first of these often being the last motor action to go in situations of this sort. This in the open access paper at reference 1, brought to my attention in last week's edition of the newsletter from the Kurzweil organisation.

I should say that I did not understand a large part of this paper, partly because of the technicalities of the machinery involved and partly (to my shame) because of the statistics.

However, the authors while doing the best they can to restore communications of a sort between these patients, their carers and family, also appear to be wondering about what exactly consciousness might mean in this context - which also interests me. And which context, more precisely, is an unpleasant variety of the motor neurone disease called amyotrophic lateral sclerosis which results in a progressive loss of motor function and eventual dependence on medical machinery to stay alive. Most patients die within 5 years of disease onset, having been locked in for the last portion of this time. It is this last portion which is of present interest.

The good news is that patients can hear, which opens various possibilities, including EEG (brain waves) and fNIRS (functional near infrared spectroscopy). Both these techniques involve fitting a sensor filled cap to the head and connecting the cap to a computer. The idea is to conduct a conversation by asking the patient questions which require 'yes' or 'no' answers, having trained the computer to be able to distinguish the patient thinking 'yes' from thinking 'no' on a battery of test questions. Questions can be as simple as 'is Paris the capital of France' or as complicated as 'are you in pain'.

What I gather from the paper is that the patient and the computer between them get the right answer about 70% of the time. A run of yes's or no's over a period of days is considered to be conclusive - but falls well short of what one would normally think of as a conversation.

My first thought was to wonder whether it was right to inflict this sort of thing on the patients. But my second thought was that the patients had had choice; they could have declined to be connected to the life support systems. By going for life support, you might reasonably be supposed to up for this sort of thing. Furthermore, it seemed that carers and family were very keen; some communication was a lot better than none.

But then I started to wonder exactly what one might be conscious of in this predicament, confined to a bed with no action and with very little other stimulation. Probably not terribly awake a lot of the time. Not even clear than showing television would be a good plan, at least in the absence of any feedback - although maybe instructions could be collected in the transition to the locked in state. Maybe one could try to sort out the patient's wishes while he or she could still express them, and just hope that he or she had made the right calls.

There seemed to be the suggestion that, with no vocal apparatus, inner verbal thought might be compromised, on which see reference 4. But that seems to be contradicted by the existence of reference 2 - to which reference 3 provides a short introduction - to which I shall now turn. Maybe worth turning up Simenon's 'Les Anneaux de Bicêtre' again: a work of informed speculation about what it might be like to be a recovering stroke patient. See reference 6.

In any event, more thought needed about all this.

The illustration is of the headset needed for fNIRS, a headset apparently mainly directed at athletes and sports scientists. See reference 5.

PS: somewhere along the way, there was the suggestion that one such patient had been asked to contribute to an important family decision. I must say that, to me, this seemed unwise. One is asking for more than can be sensibly delivered and that one is storing up anger and guilt in the case that one goes against the patient's expressed view.

Reference 1: Brain Computer Interface Based Communication in the Completely Locked-In State - Ujwal Chaudhary and others – 2017.

Reference 2: Le scaphandre et le papillon  - Jean Dominique Bauby – 1997.

Reference 3: https://en.wikipedia.org/wiki/Jean-Dominique_Bauby.

Reference 4: http://psmv3.blogspot.co.uk/2016/11/on-saying-cat.html.

Reference 5: http://nirx.net/nirsport/.

Reference 6: http://pumpkinstrokemarrow.blogspot.co.uk/search?q=Les+Anneaux+de+Bic%C3%AAtre.