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TEDx Talks
Title: Out-of body experiences, consciousness, and cognitive neuroprosthetics: Olaf Blanke at TEDxCHUV
Published: 2012-06-23
Source: https://www.youtube.com/watch?v=mD7NzrBgXwM
I would like to talk to you today about self consciousness I also prone to propose that self consciousness is based on how the brain re presents the body finally I'm going to go to my third topic which is quite if not the statics court is not the statics how I see it is a new field tries to study and build models of self consciousness in order
to protect them two artificial limbs of Atari's and robots so what is this self is the subject of conscious experience Sperry Ince's our experiences for somebody for me you we all feel this we all are introspective he linked to this who is it during this that we have which makes our experiences private but what is this entity it's actually not just experiences that are self attributed
out felt as my experience if I move my right hand this is my movement but what in the brain generates the sensation that this is actually my movement this goes for thoughts as well I have a thought right now you would have another thought to isn't ownership to those thoughts that self attribute so the self has been studied this you see on the screen over two
thousand years probably much longer mostly by philosophy more recent by a psychology and Reese most recently by corner of north scientists memories of course an important aspect of the self I remember the last time I was in was on I remember more less what I ate this morning I remember where I was them told to be born etcetera the so important aspects of the self of
all identity and people have proposed this is how we have to study the self the most famous statement in western philosophy it into the cart is marked on the screen could be too I was them I think therefore I ham so this puts really a high level commission memory the example before now thinking and thoughts it's the way we should understand the self and probably most
of us some things including me think what this must be the basis self consciousness I'm gonna argue this is wrong it starts much too high by using these Mecca's Vic scooting most of species not even in monkeys are closest relatives ocean pansies we could study this because they don't have language so we need to have an approach in our biological approach and the first approach that
people took was that so called visual a mirror self recognition task it's even some animals can pass but I'm gonna argue this is not you know eleven enough but I'm gonna I guess I told you already before is that that body representation of the brain is the most crucial and if I play you the next video please then you will see a very simple example how
we can change what is self and what is not self look in particular at the left arm off the blue subject so first of all it's it's it's always if you play this with sound it's even more fun but I mean first of all nor scientists can have fun in the bar Tory that's already a good thing not so sure about that the bluest present if
you can stop the video right now I can explain you what is actually done this is a simple trick this person lifelong experience should know what his hand is and wouldn't is not to say okay a few minutes of stroking between the hand that you see on the right he doesn't see it he only feels brushing and then there is the hand in the middle which
is seen it's a ridiculous looking fake can't we all have examples of that from the at home why this but what is done here that the experiment a puts a conflict because normally when we're looking at our hands when I touch it right now the touch queue and the visual cue was in the same position in space but what is done here simple trick the subject
even knows what it's done to him remember thought was important for the cards thought it's the same still you make an era what is your body what is not your buddy this is called the robber had delusion and has been studied by many people and can change ownership change what you judge as being your body and not your body on the next slides I show you
a few basics off the rubber hit the roof on the left side see %HESITATION that if you ask people in the rubble and it was the first in a blue shirt to ask how strongly since since Haitian that the hand that he sees a pink one here is is own hand he rates this very highly however when you put a temple conflict if feels the touch
of the hand that he doesn't see at a different moment in time then the touch she was applied on the visual hand disillusion breaks down and this is what is shown in the middle in addition this is just subjective question it changes you may ask but what is interesting here researchers have asked of the time the person there in the blue tee shirt now to point
towards the hand a very simple task you just ask the point to which you buddy what could be more simple than this you can make errors on this but if you ask the subject to do if he actually points north to Israel hand button now with ice those points shifted and drifted towards the fake cans position what does this mean but I think it means that
the brain starts perceiving not thinking perceiving that actually my hand is at the position of the pink hat and of course you can link this with cognitive nor imaging techniques that we can describe as shown in the middle we can describe the brain regions involved in this now what is necessary for this field before I go to Congress and our percentage and how this can be
used a scientific findings about the self is that we need better descriptions re not just need to stroke for one minute imagine you would be an experiment like I've just shown you but for periods of time for long periods of times several hours per day your brain would probably think and disembodied of real hand and started biting the other hand and this is actually what we've
tried to test a few examples yeah and studies developing models mathematical models when self which is ascribed to the fake hand as shown in the on the on the right side and then we've also looking at the brain signals %HESITATION that are involved in this however another example what buddy aspects of consciousness are a phantom limb since is this even one more level forward you can
feel having a body without actually having that body part attached to your body here the right upper arm of this patient is completely missing but what he feels systems of a flash like hand on the one on the right side and what is striking is that this hand here on the right side is felt in a similar way of that on the left side first I
showed you can trick part of the self consciousness in healthy subjects here you can have but any self consciousness for body parts that do not even exist and we know that this is due to the changes in the brain %HESITATION in in you can try the cortex now what is cooking dinner Pacific the first example I want to own the show you here remember cooked if
not the status protecting self foot to artificial limbs what we're trying to do and I want to show you the next video this is work by my colleague took quicken arm is that ownership and the rubber handy Losin can be induced if you have mathematical models in and I'm operationalized Altamont heist fashion so here the prosthetic limb that you see here in this patient or moving
in this patient here actually you see that this is the start of this is our left upper limb amputees touched use like in the rubber hand that you apply at the hand and that is only seen no this is a plastic hand very smart and as you can see here but these touches are linked a dedicated position onto the arm off the subject so now you
can create new a connections between a fake and and this robotic hand what is important robotic have can move as you can see but they do not feel yet I couldn't if not the stakes will allow prosthetic limbs to mediate touch sensations and ownership tools actually these mechanisms are not just at work in MPD patients under the rubber handles and we all carry tools around in
the all the time eclipse could almost be a tool but what and I've just done a talk about phantom sensations you can mount but wonder whether the stars that I grew up with I'm giving away a little bit my my age but John McEnroe what would happen if John McEnroe as he's doing now does not juice all hold his tennis racket in this lifetime we have
phantom Reckitt sensations but the data that I show you just hear next to it coming from animal experience show that this is what we should predict because I've shown you can easily change what kind of body part is yours not yours well lifelong experience holding a record in your left hand NXP change how your brain represents buddy because into using tools for several minutes per day
changes in this brain area here and the pride of cortex what the monkey's brain perceives as body or not by the so off to to use attached you apply to the finger tip activates one are on at the same nor on will also be activated when now after the tool used to tip off the tool the tennis racket in the human case is studied but to
give you one more example if you play the next video please I'm this is actually not tennis players were looking at exit what we're doing right now is surgeons in at Geneva university hospital reciting how their brain changes but not using and playing tennis but they are actually much more sophisticated using very expensive robotic %HESITATION surgery systems that allow them to improve surgery and and carry
out minimally invasive surgery so now we have for the first time the possibility to go beyond just simply hand held two words but really look at what happens if okay sorry about that if shields Robert that you've seen that's inside caring are defined operations links to fine grained finger movements how does the brain represent this I was speaking about a new brain function yes we do
this has never been possible before the question is what happens to this area the brain region that I've just described to you four what are the changes actually I think the brain will change as we move on and all of us will be in touch with more and more according to snore prosthetics but wait a minute now I've talked about self consciousness and about this entity
that is supposed to be the subject of experience to see this beautifully in these two self portraits on the left by ESR and by my off on the right this this entire entity that seems to be directed against the world it's not about hands being part of this entity or not it's me here looking at you and you over there looking at me so how can
we study this from what we've done in the lab of the last seven years is to develop methods using virtual reality in all US robotics to map into to measure what is this full body representation because what we've found is that what can be observed for the rubber handy list can also be induced in something we initially wanted to call of rubber by the illusion but
after checking though wept now and the internet for a little while we decided to go for another type of %HESITATION name for that illusion calling it the FBI or the full body but what we induce again I'll be brief is that we can induce similar state so watching bomb if you play the video in the Middle fees if you stroke now the bloody author of the
subject in the middle so you feel the touch is behind you see the touches apply to one of our cars backed extending two meters in front you do the synchronicity just like in the case of the rubber handle losing well then you will self attribute of you feel that this avatars buddies your body if we ask you after the stroking is over close your eyes with
this place you opposed to go back to your position Skase direct conflict people know exactly where they're going it's closed eyes they're working too far they're looking where they're walking they've recalibrated not that I'm position but the entire position somebody you get these two changes for the redhead who's now here for the full body bone illusion now what is interesting though what interests me in particular
here as a medical doctor by training is that there's also changes now if you and use those illusions this comes with consequences for how your brain represents your body apply touched you and people are supposed to respond very fast by a foot pedal response but there have been touched or not they get much slower spawned less well to stimuli apply to this body because we think
the brain puts their self would into that advertised by the more interesting for for medical applications support more pain apply pain stimuli during the Luzhin you waited a bit longer until you say Hey wait a minute stop this now this is getting too painful we've also looked at the brain changes again office of with that occur when this %HESITATION %HESITATION illusion occurred display the the next
videos please and we've seen one region in particular in the right temperate Prada cortex about two centimeters above to the right them of above your ear this is shown here and read in this region basically monitors under all experimental conditions that have just presented to you whether you feel self would self localized at the position off the avatar or at your body so what the basic
on trolling is inside or outside body experiences it's very easy to trick live knowing spirits into induced states and we're actually do address I do not know the subject of experience where actually the subject is localized for me this was very interesting to see because if you apply an electrical stimulation the brain of a person if the area is indicated in blue you have an out
of body experience as mentioned in the title much of this research VEF talk to you about was actually started base of clinical observations were damaged or interference to this blue region of it is very close to this other tarring coding region zetes actually has consequences there an out of body experience in this case subject feels like it's shown on the picture to be under the ceiling
be looking down so the service under the ceiling looking down while actually the real physical body still position below so what other the conclusions of what I wanted to tell you here a today first of all two thousand years of philosophy testicular chief mint and this will inspire us for still a long time but we have to stop saying that let's keep studying self consciousness experimentally
for another two thousand years I think we have to do it today and some of these experiments I've I've shown you today says action that we can change it spatial aspects of this we can change what I propose is that this for buddy representations a second part of my talk where is your body in space is actually the most simple and fundamental expense for feeding to
be someone subject of experience is related to this full body representation how the brain integrates visual tactile proprioceptive another stimulus no condition are prosthetics aims at building models of these changes and then systematically use employ them to animate if you want to incarnate brain by speaking those a artificial limbs of told you but also of our Taurus robots and other forms of surrogate buddies that maybe