FROM BRAIN TO CONSCIOUNESS

          O título desta Crônica histórica, "From Brain to Consciousness" (Do Cérebro à Consciência), é  simplesmente uma redação em inglês, de uma palestra proferida pelo Dr. Steven Laureys para um auditório na Academia Americana de Neurologia.  O Dr. Laureys, médico belga, lidera uma equipe de cientistas do Grupo de Ciências de Coma e Psicologia Cognitiva da University Research Uni.

          As declarações do Dr. Laureys, são muito interessantes. Em outro Blog (Crônicas Köhn), há uma outra Crônica Dissertativa, fruto de uma pesquisa sobre as atividades desse neurologista, e dos relatos dos pacientes após despertar de um coma profundo. Em outra crônica histórica neste mesmo Blog, este tema é traduzido para o português, para fins de um melhor entendimento da palestra do Dr. Steven Laureys.

Right.

That's B for Belgian brains.

     So, what can science tell us about consciousness?

"Nothing", some of my colleagues would say.

"We don't know what it is.  We can't define it.  Leave it alone"

I would really disagree.

     I think science can and should study consciousness.

And would like to share with you some of our difficulties in quantifying consciousness.

I'm supposed, as a neurologist, to know what I mean when seeing a patient and concluding he is comatose, unconscious or when he is recovering consciousness.

     So, how do we do it?

I'd like to have a little experiment here.  So you'll be do patients.

The first thing we will do is to reduce the complexity of consciousness to the first component:  the level of consciousness.

     So that's quite easy, I will look for scoring you wakefulness whether you have your eyes open.  OK? Those of you who are dosing in (Clapping). I stimulate you because wakefulness is necessary but, as we'll see, not sufficient for you to be aware.  Being aware:

     I'm using a slightly different  meaning here than our most famous Belgian philosopher, Jean Claude Van Damme (Laughter).  "Muscles from Brussels".  What I mean by awareness is you external awareness:  everything you see, feel, and hear right now.  That's going through your senses.

On top of that, there's internal awareness, that little voice talking to yourself, you thinking about your future, your past; internal awareness.

     That's a bit more trick for us - to quantify the content of consciousness.  And so let me please stay

with me:  assess your awareness.  I would ask you a question:  check if there is a reponse to a simple command like, "Each and everyone here, raise you right arm !"  OK.

Many did.  A couple didn't.  I'm not sure we could conclude that those who didn't are not aware.

     I think this is very important to emphasize.  What we're doing, as physicians, trying to quantify awareness, actually is looking at motor responsiveness.

Our patients in coma are often paralyzed.  So, a patient in coma, by definition, cannot be awaken.  They will never open their eyes, even if we stimulate them, and hence, they are considered unaware.

     Coma will only last for a couple of days to weeks.  Some of these patients will show some very bizarre dissociationbetween wakefulness and awareness.  They will awaken, - eyes wide open, just as you  - they would move and breathe spontaneously, but when all the movements are considered to be reflexes, we can say that they're vegetative.

     They are in a state of wakeful unewareness.  And that's very unusual.  We are not used to see people with their eyes wide open yet unconscious.  The big challenge for us is to identify, as soon as possible those small minimal signs of  consciousness.

     They can be very minimal.  And you get them now, and they're gone a couple of hour later.  This is a really a problem.  Those patients with chronic disorders of conscienceness, unconscious, in coma, can stay in this condition without any possibility of communication for years, for decades. 

     I'm afraid that medicine and society have been neglecting these artifacts of modern medicine.  So let me share threeactually, clinical realities, extraordinary realities.  The first one are those patiens who, after a severe brain damage, that can be a trauma or a cardiac arrest, are in coma and then evolve to brain death.  That is when all brain function is gone.

     So here I think it's important that we use these new technologies.  You see an image where we inject sugar, radioactively labelled glucose.  It goes into the brain that uses a lot of energy.  And so, you see in your brain right now, I hope there should be a lot of activity in your Grey matter, in your cortex.

     Those billions of neurons, all red and yellow, are using a lot of sugar.  In brain death, we see the empty skull sign;  it's only the skin surrounding the skull that is still using some energy, but not those billions of neurons. 

          Here, you can safely donate your organs.  Because yes, we do have scientific evidence that there's life after death: it is called "organ donation".
And it's very important (applause), It's very important;  physicians are very transparent about it.

     We are not used to see somebody in intensive care, the heart is beating, they feel warm, breathing to the machine, and when the brain is dead, you are dead.  I think it is very important first and extraordinary clinical reality.  Another one I would like to briefly touch upon are those patients who survive their coma.

     They will tell us afterwards they had these extraordinary experience:  they left their body, they saw a light and their relatives, they felt good; these near - death experiences.

     Again, I think that science and medicine have neglected this reality for far too long.  So I have a little request if anyone here had a near - death experience or knows somebody who had,  please come and contact us because I think science should study these phenomenon scientifically.

     The third extraordinary clinical reallity is indeed these patients who survived their coma awaken, yet, remained unaware.  These patients are a so-called vegetative state - unresponsive wakefulness - where with these brain scans, as you see, we can show that there is a very abnormal brain activity.

     It is Al blue. It's less than half of the normal values we see in normal consciousness.  I think one of our important discoveries is that we were able to, for those patients who recovered from this condition, the vegetative state, do this study again.  What we saw is not that the brain resumes a normal activity all over.

     It just recovered in some specific parts of the brain, in other words, you don't need your whole brain to be aware.  I think this is very important: to be able to identify the critical brain network.  You see it there.  It's not a small consciousness region.

     It's a network:  in red, the external awareness net work, but sides in the front and the back.  And then, in blue, the mid-line, front and back again, this internal awarenessnet work important for you to have these internal discussions.  The arrows are there to show how important it is that these networks communicate with each other, that they interacts within and between each other.

     You could say, "Why would this matter?"  Well, I think there is maybe three reasons.  First of all, it does matter whether a patient is fully unconscious or whether there is a little bit of consciousness.  For example, for our treatment of pain.

     Again, we can use these new machines, new imaging tools to go and look at what's happening in your brain when you fell pain.  It's not a small spot.  It's a network, as you see it in these transparent brains.

     When you look at brain death, there is no activity whatsoever.  No brain, no pain.  Patients (laughter) who are surving their coma involve to this bizarre dissociation of vegetative state,  wakeful unawareness.  They will activate their brain stem.  This is deep in the brain.  It's important for wakefulness.

     And also, you see, a bit of their cortex.  But this is the sensory cortex.  It's like a slave system.  It's isolated, it's disconnected from this awareness network, so it's not enough for you to have a conscious experience.  I think it'svery important that we observe that those patients with very small signs of consciouness - like following with their eyes or sometimes responding to a command - showed the whole pain network that was activated.

     In other words, these patients can't, by definition, communicate that they would fell any pain, but their brain scans tell us we should systematically treat them for pain.  This brings me to the next important issue of trying to give these patients a voice, trying to use these technologies to establish  a communication.

     This is an image of the fist patient ever on this planet where could use functional imaging to establish a form of  communication.

     

     Where we could use functional imaging to establish a form of communication.  This patient was to Liège with this label "vegetative".  We put him in the fMRI scanner, and we saw this activation when we asked a question.  You see the activation is the blue spot.  It's a very damaged brain so there is a lot of black there.

     The black is the fluid actually the place of the brain.  There is, at some places, very little brain left. Again, you don't need a lot of brain to be conscious.  We can use this with some tricks to read, when we see blue, it's a "no", when other areas in red activate, it's a "yes" and it's a "no".  We can communicate only with these novel technologies, really giving some of these patients  -  this exceptional - their right for autonomy.

     The third reason, I think, is these new imaging technologies permit us to better assess the chances of recovery.  And therefore, we use...  I'd just like to show this little object, wich is my brain printed in 3D, it's the connections within my brain.  I think it's beautiful (laughter).  So I took spare brain today.

     When we measure this in patients with severe brain trauma or after a cardiac arrest,  we can use this information to predict the outcome to make the right decision when there is no chance of recovery, when we should increase all our efforts.

     That's of course, a very important life or death decision where these measurements, I think, will help us in the future.  So in some, I think of coma and related conditions has permitted us to identify the critical brain networks for awareness.

     And it's my hope that as an integrated, international scientific effort, will use information and will continue to increase our undestanding of the mystery of consciousness and then use that knowledge to improve our care for these very vulnerable patients with chronic disorders of consciousness after a severe brain damage.

Thank you for your attention (applause).