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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
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