Out-of body experiences, consciousness, and cognitive neuroprosthetics: Olaf Blanke at TEDxCHUV

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 represents the body and finally I'm going to go to my third topic which is cognitive neuroprosthetics cognitive neuroprosthetics how I see it is a new field which tries to study and build models of self-consciousness in order to project them onto artificial limbs of Attar's and robots so what is the self the self is the subject of conscious experience experiences are experiences for somebody for me for you we all feel this we all are introspectively linked to this to this experience that we have which makes our experiences private but what is this entity this is actually not just experiences that are self attributed up 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 will have another thought there is an ownership to those thoughts they are self attributed so the self has been studied as you see on the screen over 2000 years probably much longer mostly by philosophy more recent by psychology and Reiss most recently by cognitive neuroscientists memories of course an important aspect of the self I remember the last time I was in Lausanne I remember more or less what I ate this morning I remember where I was told to be born etc these are important aspects of the self of our identity and people have proposed this is how we have to study the self the most famous stay in western philosophy at any the card is marked on the screen cogito ergo sum I think therefore I am so this puts really a high-level cognition memory the example before now thinking and thought as the way we should understand the self and probably most of us sometimes including me think well this must be the basis of self consciousness I'm going to argue this is wrong it starts much too high by using these metals we are excluding most of the species not even in monkeys or closest relatives or chimpanzees we could study this because they don't have language so we need to have an approach a neurobiological approach and the first approach that people took was the so called visual mirror self recognition task which even some animals can pass but I'm going to argue this is not low level enough but I'm going to argue as I told you already before is that the 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 itself and what is not self look in particular at the left arm of the blue subject so first of all it's always if you play this with sound it's even more fun but I mean first of all neuroscientists can have fun in the laboratory that's already a good thing not so sure about the blues person if you can stop the video right now I can explain you what is actually done this is a simple trick this person live long experience should know what his hand is and wouldn't is not his hand okay a few minutes of stroking between the hand that you see on the right he doesn't see it he only feels the brushing and then there is the hand in the middle which is seen it's a ridiculously looking fake hand we all have examples of that probably at home more or less but what is done here that the experimenter puts a conflict because normally when we're looking at our hand when I touch it right now the touch cue and the visual cue is on the same position in space but what is done here simple trick the subject even knows what is to him remember thought was important for the cart thought is the same but still you make an error what is your body what is not your body this is called a rubber hand illusion and has been studied by many people and can change ownership it can change what you judge as being your body and not your body on the next slide I show you a few basics of the rubber hand illusion on the left side you see that if you ask people in the rubber hand illusion the person in blue shirt to ask how strong a sense sensation that the hand that he sees the pink one is his own hand he rates this very highly however when you put a temporal conflict if he feels the touch of the hand that he doesn't see at a different moment in time then the touch cue is applied on the visual hand this illusion breaks down and this is what is shown in the middle in addition this is just subjective questionnaire changes you may ask but what is interesting here researchers have asked so the I am the prisoner in the blue t-shirt now to point towards the hand a very simple task you just ask the point towards your body what could be more simple than this you can make errors on this but if you ask the subject to do it he actually points not to his real hand but he now with eyes closed points shifted and drifted towards the fake hands position what does this mean well I think it means that the brain starts perceiving not thinking perceiving that actually my hand is at the position of the pink hand and of course you can link this with cognitive Nora imaging techniques and we can describe as a shown on the middle we can describe and the brain region involved in this now what is necessary for this field before I go to Congress Nora prosthetics and how this can be used these scientific findings about the self is that we need better descriptions we not just need to stroke for one minute imagine you would be an experiment like I just shown you but for periods of time for long periods of times several hours per day your brain would probably think and disembody the real hand and start embodying the other hand and this is actually what we've tried to test with few examples and studies developing models mathematical models when self would is subscribed to the fake hand this is for shown on the on the right side and then we've also looking at the brain signals that are involved in this however another example what body the aspects of consciousness are a phantom limb sensations this is 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 is the persistence of a flesh like hand on the on the right side and what is striking is that this hand here on the right side is felt in a similar way as that on the left side so first I showed you we can trick bodily self-consciousness and healthy subjects here you can have bodily self-consciousness for body parts that do not even exist and we know that this is due to the changes in the brain in in private cortex now what is cognitive neuroprosthetics the first example I want to I want to show you here remember cognitive neuroprosthetics is projecting selfhood to artificial limbs what we're trying to do and I want to show you the next video this is work by my colleague Todd quicken is that ownership and the rubber hand illusion can be induced if you have mathematical models in an operationalized automatic iced 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 stump this is a left upper limb amputee and touch cues like in the rubber hand that you apply at the hand and that is only seen now this is a plastic hand a very smart hand as you can see here but these touches are linked a dedicated position onto the arm of the subject so now you can create new connections between the fake hand and this robotic hand what is important robotic hands can move as you can see but they do not feel yet so cognitive neuroprosthetics will allow prosthetic limbs to mediate touch sensations and ownership tools actually these mechanisms are not just at work in amputee patients and in the rubber hand illusion we all carry tools around in our hand all the time actually cloth could almost be a tool but what and if we've just talked about phantom limb sensations you can under weather these stars that I grew up with giving away a little bit my my age but John McEnroe what would happen if John McEnroe as he's doing now does not use or hold his tennis record in his left hand will he have phantom racquet sensations but the data that I show you just here next to it coming from animal experience show that this is what we should predict because I've shown you you can easily change what kind of body part is yours or not yours well live long experience holding a record in your left hand can actually change how your brain represents body because in using tools for several minutes per day changes in this brain area here in the parietal cortex what the monkey's brain perceives as body or not body so after to use a touch cue apply to the fingertip activates one neuron and the same neuron will also be activated when now after that we will use the tip of the tool the tennis racquet in the human case is studied but to give you one more example if you play the next video please this is actually not tennis players we're looking at actually what we're doing right now is surgeons in a Geneva University Hospital we're studying how their brain changes but not using and playing tennis but they are actually much more sophisticated using very expensive robotic surgery systems that allow them to improve surgery and carry out minimally invasive surgery so now we have for the first time the possibility to go beyond just simply handheld towards but really look at what happens if okay sorry about that if this huge robot that you have seen that's inside carrying out the final operations it's linked to fine-grained finger movements how does the brain represent this are we 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 before 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 cognitive neuroprosthetics but wait a minute now I've talked about self consciousness and about this entity that is supposed to be the subject of experience you see this beautifully in these two self-portraits on the left by Usher and by MA on the right there is 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 it's me here looking at you and you over there looking at me so how can we study this and what we have done in the lab over the last six seven years is to develop methods using virtual reality and also robotics to map and to measure what is this a full-body representation because what we have found is that what can be observed for the rubber hand illusion can also be induced in something we initially wanted to call a rubber by the illusion but after checking the web and the internet for a little while we decided to go for another type of name for that illusion calling it the FBI or the full-body illusion but what we induce again I'll be brief is that we can induce similar states so watching if you play the video in the middle please if you stroke now the body of the of the subject in the middle so you feel the touches behind you and you see the touches apply to an avatars back that's standing two meters in front and you do this synchronously just like in the case of the rubber hand illusion well then you will self attribute or you feel that this avatars body is your body if we ask you after the stroking is over close your eyes we displace you and you're supposed to go back to your position in this case the red carpet people know exactly where they're going but with closed eyes they're walking too far they're walking where they're walking they have recalibrated not the arm position but the entire position of their body so you get these two changes for the rubber hand illusion now here for the full-body illusion now what is interesting or what interests me in particular here as a medical doctor by training is that there's also changes now if you induce those illusions this comes with consequences for how your brain represents your body if you apply a touch cue and people are supposed to respond very fast by a foot pedal response whether they have been touched or not they get much slower they respond less well to stimuli apply to this body because we think the brain puts their cell foot into that avatars body more interestingly for or for medical applications you support more pain so if you apply pain stimuli during the illusion you wait a little 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 of this off that occur when this illusion occurred please play the the next two videos please and we have seen one region in particularly in the right temporal parietal cortex about two centimeters above and to the right of above your ear this is shown here in red and this region basically monitors under our experimental conditions that I've just presented to you whether you feel Salford self localized at the position of the avatar or at your body so what we're basically controlling is inside or outside by the experiences if you want so it's very easy to trick lifelong experience and to induce States and we're actually you do errors you do not know as a subject of experience we're actually the subject is localized it for me this was very interesting to see because if you apply an electrical stimulation to the brain of a person at the area that is indicated in blue you have an out-of-body experiences and this was mentioned in the title much of this research that I've talked to you about was actually started based on clinical observations were damage or interference to this blue region which is very close to this avatar in coding region leads actually has consequences there an out-of-body experience in this case the subject fields like is shown on the picture to be under the ceiling to be looking down so the self is under the ceiling looking down while actually the real physical body is still positioned below so what are the the conclusions of what I wanted to tell you here today first of all two thousand years of philosophy it's great it's a fantastic achievement 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 shown you today says actually that we can change it spatial aspects of this we can change and what I proposed is that this full-body representation the second part of my talk where is your body in space is actually the most simple and fundamental experience for feeling to be someone a subject of experience is related to this full-body representation and how the brain integrates visual tactile prop receptive and other stimuli now cognitive neuroprosthetics aims at building models of these changes and then systematically use and employ them to animate if you want to incarnate brain-wise speaking those artificial limbs i've told you but also avatars robots and other forms of surrogate bodies that maybe we don't yet know how to think about it and how to conceive them the first subjects people who will probably try these technologies and we're actually having several ongoing studies in this field of cognitive neuroprosthetics is tetraplegic patients or other patients suffering from spinal cord damaged there is a massive disconnection from the body depending on your level of brain damage so you have a body but you don't feel it it's very similar to actually phantom limb sensations functionally speaking so what I would propose is to give these patients back a feeling of their body and to alleviate pain of this body but because in some of these patients actually they not only not feel the body but the bit of the body is per se perceived as painful actually the technologies I've presented to you can change those two aspects entertainment may also profit from this video conferencing and video phoning has completely changed how we used to orally or verbally communicate but it still I think has a long way to go what I propose here is also that cognitive neuroprosthetics projecting salford to a virtual world where you have an avatar and you meet your friend joining in as a virtual avatar from Australia made change how we communicate and may facilitate communication even further meeting literally speaking and I finish with this last video here that I also think for gaming projecting yourself into the character into the game and something first-person perspective games if you can create games where actually your brain believes you're literally in the game I think that will make for very interesting games at many levels of this field for example in the video that I show you here the person or the self representation is shown in this red avatar running in front of you now imagine that you can trick your brain to is very strongly believing that that is really you literally you will be in the movie in this virtual reality scenario thank you the final forgot to say the final a final conclusion I will say thank you again after this is that I believe in order to achieve this and to achieve this fast it needs a merging of several disciplines working on the same target problem this is neuroscience computer science engineering and last not least medicine thank you

Channel: TEDx Talks

Views: 475,948

Rating: 4.7728643 out of 5

Keywords: inside-body, phenomenon, tedx talk, cognitive neuroscience, Science, robotics, virtual reality, ted, ted talk, tedx, Switzerland, neurology, brain mechanisms, ted talks, English, conscious self, neuroscience, bodily mechanisms, ted x, TEDxCHUV, tedx talks

Id: mD7NzrBgXwM

Length: 18min 55sec (1135 seconds)

Published: Sat Jun 23 2012