Hi, everyone. Do you hear me? Do you hear me? Okay. Hi, everyone. If you can take your seats and settle down, I can. Make some concessions. Okay. So today we're going to talk about technologies to treat neuro disorders. And this is kind of a follow up of this week's series of lectures, which is about kind of methods and techniques that are used for neuroscience in general brain and behaviour. So just a bit about myself. I actually started off as an engineer, which is probably why they picked me to take this lecture so I can talk a bit more details about that stuff, but you won't be examined on that anyway, so. Okay, so how can we use technology to treat neuro disorders? There's basically three main ways in which we can try and get at this kind of three broad categories. One is to use it to read from neurones. So this is something where you can use prosthetic devices that are controlled by interpreting neural activity or something like that. The second is to actually write to neurones. This is something where we try and look at something that's happening in the external world and try and write into right to the subject's brain directly. And the third is to actually just use it to control abnormal activity. So this is something where we have something like a pacemaker to control abnormal brain activity. So I'll cover these three during this lecture, mainly focusing on the first two. So in terms of the first one, you might have. So if you're trying to read from neurones, there's three kind of stages to it in general. The first thing is we need to be able to observe neural activity. So what's happening in the brain? You want to try and read that first, interpret this activity, to try to understand, well, what's happened, what's the kind of process that the individual or the subject is trying to do? And finally, then control or manipulate an external device. So in general, the last bit, which is about controlling and manipulating external devices, is more of an engineering problem. So we're not going to get into that. The main focus is going to be on observing neural activity, which is something where you need a recording device and this is kind of using neuroscience to try and develop these ones. And then we need to understand this by using some kind of computational approaches and in combination with an understanding of what the brain is doing. Okay. So what type of activity can actually be used? I mean, when I talk about observing neural activity. So this is something you might have covered, Sam Solomon would have covered in the previous lecture. The first thing is something like recording spiking activity, which is the firing of action potentials across a population of neurones. This could be either by implanting electrodes into the brain or reading from peripheral nerves in around the body. Another technique that could be used is ephemeral, kind of. Briefly touch upon that. And finally, something that's broader at a larger scale is using things like brain oscillations or EEG. So electro echo or electro cortical grabs, which is something that Sam would have covered, but it's something where we've kind of got either an external device or something like a. Cat. That's recording oscillations still. How do we then use it to how do we interpret the activity and control a device? So a third of it, the broadest device, which is the EEG, it's a non-invasive technique. So what we record is neural oscillations. These are brainwaves or from large regions of the brain. So as you can see this, it's just a. Cat which. Is looking at different. There's multiple electrons placed across the across the head. And you just basically looking at the electrical activity around that, around each of those points and using that, you can slightly localise what's happening in the brain. So what we can actually interpret is quite coarse because it's kind of recording from large regions of the brain. It's not something we can get very specific information about, but kind of contrasting activities between different regions is something like left versus right side of the head or the front in the back. And so given that it's very coarse measurement, what we can actually do is get very coarse control over things. So you can get something like you can get yes, nuances or something where you can move forward or move backwards and so on. So that is going to show an example of this in action. So this lecture is going to have a lot of videos because I think the best way to actually see what's happening, it's quite dramatic. But something. Like 50 different. Countries in the Middle East. Okay. So as you can see, this subject is able to control the wheelchair based on this new act, based on this age group that is thinking about something or based on what he's thinking or what is in this case, he was moving his head down as well. Based on what he's doing, he's able to control the wheelchair. But know that, you know, this is quite something complex happening in terms of like going up the stairs and so on. Is this probably not being controlled by the by the device? Because, as I said, it's quite coarse measurement. So what he's able to do is something like move up and down. They're just moving the wheelchair up and down or maybe move the wheelchair forwards and backwards. So there's like some amount of control that he can have, but that's about it. There's another this is it's a link to a video which is probably going to show as an idea. I know it's for you to watch later. It's I just put the link up there, but it's got quite a detailed explanation. If you're interested of how a group of students from a school come together to actually build a wheelchair that's based on EEG. So it's a group of like I think ten students and they split the problem up into the various aspects. So one team is doing kind of the EEG aspect in the data collection. One team is each there's like multiple teams doing these things. And finally they're able to control a wheelchair based on just the EEG. Okay. So one other thing is, like, this is quite a cost measurement. So in some cases what you have is what you can do is rather than use, try and interpret what exactly the brain is saying. So, you know, if you're trying to, you know, grab something and and do something, it might be quite hard to interpret that fine scaled action using this such a coarse measurement. So what you can do is do some. Hacks. And this is an example of that. To demonstrate how this technology works. Well, you get some studying nonverbal communication you can do. A lot of people are learning. What. It's like to get a lot of different types of responses, like the specific one picked up by the victim or. And nobody reported. Well, I that. Frequency of no. Except for, you know, the computer interpret the signal to give the correction some response. So the reason I picked this video is something where what they've used is kind of a hack of trying to control this, trying to get some answers. So they put this flashing light one a 12 hertz, one and 13 hertz. And it's just when you look at a flashing light, you're visual cortex usually lights up, tries to go between certain frequencies. It follows what's happening with the lights. If it's if it's oscillating, if the light is oscillating, the visual cortex is going to oscillate in in sync with that. And so they're able to just detect what the oscillation frequency is, and they're using that as kind of a hack to try and look at like, does a subject want to go left or right? So it's kind of a binary answer or. It's a binary answer and they're able, but it's quite effective at trying to get this subject who is immobile to. You can read their brain in a sentence, as I said multiple times. Now the limitation is it's a very close spatial resolution. It's the amount of information you can get is quite limited. So we can now move to another non-invasive technique, which is MRI. And you might have heard about this before. It's something that records blood oxygen levels in the brain. And we can interpret this based on the activation levels from different regions of the brain. And this is kind of going from the very coarse resolution of a few of multiple millimetres in the EEG to something more at a millimetre scale or this quite low temperature resolution. So you need like hundreds of milliseconds to actually interpret the activity. So it's a really cool demonstration that was there a few years ago. It has actually gotten a lot better in the recent years, but here's an example of it. So let me just explain what this is showing. So this is the movie that is presented to the A subject. This is a variation of that which is just they're just looking at what are the edges in that image And this is what is decoded. So you look at the brain activity in the scanner and based on the activity of the brain, they actually just trying to try and decode or guess which movie was presented based on the brain activity. So this is. So. Yeah. What's happening there. But in. General. We have to do things. Okay. Anyway, in general, what you would see is that as in this example here, you don't quite get a perfect match of what the subject is seeing, but you see some approximation of it. So it's it's it's decent, but it's it's, it's just an approximation. Again, here edges are slightly better in the movie. If you see the movie, it's usually. Okay, maybe with back elements. If you see the movie, you can see that it doesn't quite always get it right. There's there's a lot of variations in general. So one of the major limitations of ephemera is the fact that it's a huge device. So this is like it takes usually it takes a whole room and another room to have like a cooling system and so on. So it's something that's not really practical to use as a day to day device to kind of help treat or to use as a neural interface. I really hope the following videos work, but so another option is to record from periphery nerves. So this is where it's cool. So far we've been talking about recording from the central nervous system, so just the brain as such. But there's a lot of nerves in the in the body and sometimes maybe it's more effective or easier to actually get to the periphery. There's a few advantages, advantages to this. The first thing is you don't need to get to the skull where, you know, implanting anything or interpreting activity through the skull is actually quite a big challenge. So you can get across that by recording in the periphery. And this is I really hope it works an example. Okay. This is an example. So this particular subject has two kinds of prostheses. The prosthesis is either controlled by a electrode that is placed on the surface of his arm and shoulder, or there's a there's a second option, which is that they actually implant the electrode into the arm and the aid record from within the neurone as such. So the idea this demonstration is basically showing how by implanting the electrodes into the body, you're able to get better control because there's a little bit more information. So as you try to record from outside, the information is a bit more noisy in terms of as a recording technique. So this is an example of him trying to control holding an egg. You can see that with the external electrodes he is able to control it, but he's not able to control every aspect of it. And that's something where you can imagine the number of things that are needed. So in general, I was talking to you about like. Yes, nuances in the. We can just watch this again. So the surface electrodes. He's not able to really control it. Hopefully. Implanted electrodes and you can see that it's a lot better. The fact that he's able to do either just control the arm is actually quite amazing compared to what we used to have, where you just have like a phantom thing which is just attached to the body and you kind of passively control it. So in this case, this device is actually integrated into the kind of the periphery nervous system where the subject is able to control kind of the action of light, how much is moving, grabbing something and moving it in different directions. So going back a little bit to what I was saying before with the EEG, it's kind of, yes, the onesies or maybe for four ounces. Here again, you've got your recording from various neurones and you're trying to get a few different quick answers. In the case of the prosthetic arm, it's how much you want to press. How how do you want to grab something? So if it was just like grab and release, that's probably something you can get from a surface electrodes. The more information you have, the more accuracy you can get at various things. So that's the general idea of the difference between the surface electrode and the implanted electrode. And this kind of holds across various devices. So the more information you have, the more accuracy you can have in controlling various things. So this is just an example of a periphery system. And here we're recording the neural activity of individual or sorry, that was the periphery neurones. And I guess one of the limitations here is that. But in this particular case, it was pretty clear that the prosthetic arm was something that just the subject needed. But if you want to try and control, let's say, like a wheelchair or something, maybe you don't have access to these with these nerves. A lot of these the videos I'm going to show you next are in paraplegic subjects who really can't actually control any of their nerves, make them. So in that case, you need to then go up and record from the brain directly. And in this case, what you're able to record is actually a neural activity from an individual or a collection of neurones that are in the brain. And given that you're actually recording from within the brain, you can now record from a large number of neurones and you can record spiking activity at a higher temporal and spatial resolution. So I just show an example of things that showed some of this in general. So this is a braingate system which has been deployed in human subjects. This is an example of what the electrode looks like. So there's like a ten by ten grid of electrodes. It's about this big you can see in a human now, and this one is implanted usually within the brains around the motor cortex or this embedded sensory cortex of some subjects. So just to show you. This is why we call it. I think I'm showing you a bit of this video before I like to show this as an example, where this patient who's. Out. Here is abled is controlling an arm using one of these systems. And this is an example of her trying to drink coffee, have a sip of coffee from this. From above. By controlling the robotic. Arm. Then when you watch the video, you can make note of the fact that it's around 140 at a time. Samba was at 140 with in the video. You can have a look at this later. But it's something where it's quite moving because it's the first time she was able to actually actually control something by herself and then have a sip of of coffee from there. One of the things to note and this is like, as I mentioned, this is a huge engineering feat to get like an arm, a robotic arm to do something like this. So a lot of these technologies are also based on some very cool engineering that goes into the backflip. I'm not going to show, if I can, a newer version of this. Oh. Okay. So in this case, this subject again, it's got this BrainGate device and very able to browse the Internet. And usually what that is, is like you've got the cursor here bottom, it's the other video. So what this subject is able to do is actually control the cursor on the monitor. Then again, by controlling the cursor on the monitor, they're able to type in an email. Okay, So this is kind of where this is at. They're doing a lot of human tests. But as you can see, it's ethically it's basically something that you would use for paraplegic patients where they're unable to use. There's very few other options for them to actually try and interact with the world. So I'm finally going to show you something that's beginning Looking to the future. This is a demonstration by model group. Sorry, let me shut my female. Yeah. This is a demonstration from Elon Musk's team that are. So just to give you an idea of what they've come up with is as he does, he started a new company that is trying to revolutionise neuroscience. But anyways it's debateable. But one thing that they've definitely been quite successful at is developing some of these devices. So what you actually see here is a robotic device that's used to implant electrodes into the brain. And the reason for that is they've come up with this new electrode design, which is quite like what you saw before in this slide was this kind of device. Now, this is this, as you can see, the rigid structure that is placed on the surface of the brain. Neuralink instead has come up with a new version of it, of a new design where you've got independently movable electrodes. This is something that we usually use in the lab, but more but not as many simultaneous people. So they actually put in like about a thousand electrodes in to try and target individually different brain regions. And that then goes into this device, which is which is really tiny. And that's actually one of the innovations of the company. It's quite impressive. It's it's about the size of a coin, maybe like a pound coin or something like that. And so it's also quite thin and can it is within the thickness of the skull. So for a human skull and in this case they demonstrated on pigs. And so it's also within the thickness of a pig's skull so they can just implant it. So it's flush with the the surface of the of the skull. And another innovation that they came up with is when you look at the BrainGate videos, you see that there's this big cord coming out, there's this big device attached to the head, and then there's a big wire coming out instead. The other innovation that the companies come up with is that they've made everything kind of via Bluetooth. So it's wireless and so it's just on the skull. You can actually have. A go back or. You can have like the skin cover up that area once, once everything is done and then everything's going over wirelessly. So this is a demonstration of this is. Actually, this animal actually has. This animal actually has an electrode implanted in it. You just don't see any any sign of it. It's it's moving around really healthy. And so now this is where they're going to move it into an area where it can actually get to wireless signals. Okay. So the recording from like thousands of neurones, then each of these each of these rows here represents the action, an action potential firing from an individual neurone. You can see they're able to actually like while the pig is moving around, you can see looks is. Happening in real quick signals. So literally neurones that are out over here and put them on a virus which is affected here. Okay. So I was just going to show you another towards the end of this video, they're looking at like how they can interpret the activity. It's a while that hopefully loads up. So it's a bit of a weird system. So one of the things that Neuralink was it's quite controversial among neuroscientists because they kind of said it is this big advance. But in terms of to the neuroscience end of things, there's actually like a lot of what they've been talking about is something that we've known, for example, the BrainGate system, it's been there for over ten years now and it's something where you can actually decode activity in control devices. Okay. So this is an example. Of a digital activity. An example of a pig running on a walking and a treadmill. And by recording from the motor areas of the brain, they're able to actually decode the positions. I've been reading they're going to look like on that record. And we think that the photographs and records submitted. Okay. So just this that's just trying to predict various points on the limbs of the limb of the animal. And you can see that basically the actual limb position versus the predicted limb position, it's quite accurately decoded. So the mission statement of the company is kind of weird. They want to have everyone have access to these things, but that's kind of scary to me to enhance your brain. It's scary because you need to put something in the brain and make a big hole in your skull. So now they've kind of toned it down. They're talking about, Oh, we're going to use it for paraplegic patients. So they're getting human they're they're kind of getting to FDA. I think they've got FDA approval to test in paraplegic subjects who similar to the BrainGate device. And so I think that it's pretty cool for that. I just don't know how they're going to. Make. Money off of it like they want to. But it's a pretty cool tech and lot of innovations on the engineering end of it in terms of being able to record neural activity. Hopefully they bring it back, they send it back to science. Right now, everything's closed. We don't have access to any of these technologies. Okay. So the limitations, as you can expect, it's highly invasive. So again, you need to put these electrodes into the brain so it's not something that you can do that easily. And like I said in the beginning of the Neuralink thing, you've got this huge robot that they've actually designed and that's part of their part of their innovation that they needed to develop this robot to be able to implant these electrodes. Okay. So I've just reviewed a few different ways in which you can read neural activity. I'm going to skip ahead now to the second part of the talk, which is about writing to neurones. And this is something about transmitting information that a subject cannot access. And for this, we kind of. Rather than go this way, we have to go the opposite way. Who would observe or monitor the external events, interpret this information, and then edit neural activity to send it back to the brain. So how can we edit or manipulate activities? It is generally, there's a few different ways you can either electrically stimulate neurones. This is the most common method and this is something I've been talking about mostly. And then there's also a possibility of using magnetic stimulation. It's much more cause they're not that well understood. It's a very commonly used. And then more recently, there's something like optical stimulation, where you use some genetic approaches to make neurones fire when you shine light at them. Chemical stimulation is possible, but it's very hard to have precision in terms of controlling that. So I'm going to jump straight into cochlear implants, which is probably the most impressive and most commonly used brain machine interface. So this is the issue is that there's loss of hearing due to some issues in the early stages of auditory processing and by early stages that's around this region here before the auditory nerve, there's there's issues that are happening before the auditory nerve. So one of the advantages and one of the reasons why this has been such a success story is because of the structure of the ear and the auditory nerve, and that's specifically the cochlear of the. Of. The cochlear system. So this is an example. This is kind of an illustration of what the cochlear is, is is this this bit here it's the coined surface. And at different parts of the cochlear, the auditory nerves kind of go along different parts of the cochlear. And just based on sound frequencies, the way sound travels through the surface, it attenuates different frequencies at different points. So it's a beautiful design of evolution and it's the way it takes advantage. So you've got the highest frequencies at the outermost point of this. So this is around 20 kilohertz and you go down up until like a 200 hertz region that's at the apex. So this is kind of the the structure of the human cochlear. I illustrated here where you've got like the different medium frequency coming into the middle and then the lowest frequency waves reaching all the way to the apex so that the auditory nerves kind of in a way, different regions of this. And so in a sense, what this the advantage of this is this has brought all of auditory processing, which is quite a complicated process into a single one dimensional axis here. So this is one long. So if you stretch out this coil, it's basically one thing, one long stretch of tissue. And the advantage now is that if you estimate a different point of this tissue, they're able to generate different perceptions of different sounds. And that's what is taken advantage by the cochlear devices. They have a device that goes all along this. Coil and. It can stimulate different portions of this. So this is what a cochlear system would look like. So on the external side of things, you've got a recording device that this is something that's recording sounds from the outside and it's kind of doing some amount of processing of those sounds and then transmitting this to a transmitter that's on the surface of the of the skull. And then internally you've got a receiving device that's there just just on the inside of that. And then you've got another kind of stimulator or kind of a processor there and then goes into this coil device that going all along the cochlear. And you can see there's these different bits here. These are like the electrode sites and this is the electrodes that are able to kind of the cross currents to stimulate different portions of the of the cochlea. And by stimulating different parts of the cochlea, they stimulate different sound levels and different sounds. And so by having like a nice simple linear transformation and then because it's an electric signal, it's quite fast. So you can have, you know, as I'm speaking, all the different frequencies of sound that I'm conveying, are able to, you can actually process that and get it to all the different points at a very fast times. So that's the kind of advantage. And I'm just going to show you this video here, which you can watch later. It's the nice description of a doctor describing how a cochlear works. But what I find really moving is this is this is a documentary. I would highly recommend watching all of it. At some point, I'm just going to. The complete 100% sound science. What can happen? I hear what I'm saying and how it sounds because I know it sounds different. But this I find that my voice is back to normal. Hi. Makes me 70% or so. So I usually show a longer plate of the clip. I just realise it's too late. But if you noticed that her voice was changing, she took out the implant. And actually, if you saw it from earlier, it progressively gets worse and worse as she's speaking. And you can also see her getting not very confident and as she says, insecure. And then as soon as she puts it on, the voice changes completely. And that's just the fact that she gets this feedback. Rather than putting our accessibility first. We want to get people who. Actually. Complete 100%. I'll go back a little bit because. I think so. What kind of stuff? I take it off, so I keep it off for the more exciting stuff, seems to become more convoluted and becomes more difficult to think about what they ought to be something. You know what I'm saying? Because I don't think it's a matter of speaking to the cow when I pick my husband so I can hear people. So I'm not even being a complete 100%. So what's possible? So I'm a little insecure about what I'm saying because I know it sounds different. But the 70 seconds and trying to keep things back to normal, I think means. I think that one might have been clearer as you saw the progression as well as how the design changed. So you can see it's actually a really for me, this is probably the biggest success stories of a neural interface that you. So you need to have something. The deftness where it works is something where the auditory nerve is intact and then like further on, it's able to it's able to process. And most of the hearing disabilities come from kind of early hearing, early stage hearing loss. So it is quite. That's why it's so commonly used, because it's kind of an early stage thing. So moving on from hearing actually, the next one would be, well, can we actually then take this into the eye, which is the other sense. Organ or. Something? So. So this would be something where if you have loss of vision at the level of the eyes. So again, like there's quite a few issues that do happen at the eye. I think vision has a broader range of issues happening in general. So as I mentioned, the the auditory system had this nice coiled structure that actually just boiled down to like a single thing. So when it comes to the eye, it becomes you've just added another dimension. Now things are in 2D, you've got like a 2D scene that you have. You could argue that that's there in the auditory system as well, but at least the amount of information you can get across with this one dimensional structure is sufficient for a subject to get a good perception of things. But with vision, it tends to be a lot harder because you've got you've got a lot more detail in structure and we're kind of used to seeing this amount of detail. So it becomes harder to and again, you've moved from a one dimensional structure. Now you've gone to a flat surface, which is the retina here, and you've got like a two dimensional structure. So the general idea of how an implant like this would work is that you have a camera that's, you know, subject with bathroom glasses, with a camera attached on them. They've got some kind of processing that's happening on an external unit that then gets transmitted into the device that's within the eye, and then that goes onto a kind of a chip that's then this retinal implant that's then stimulating either electrically or optically. It's the surface of the retina. Now, one of the issues with this is that actually there's a lot of different receptors in the eye. So it's not just about, you know, on off in one retina region, you have colours, you have edges, you have lots of different things. So what you would get is kind of flashes of light at different parts of the of your visual field. So it's not quite detail information that you would, that we would usually do so wouldn't be able to see faces or recognise faces but kind of a flash of image. So in general I think the target of this is to help subjects get some amount of information which would help them with their day to day lives through something like if you're a child across the road and there's a car coming, you could flashlight light towards which part where the car is coming or something like that. But it's not something where you would be able to get a subject. You read a book or something as detailed as that. So it it is a much more challenging area, are trying to get a device into the eye. There's been a lot of attempts at it, but it's been quite challenging at the same time. There's also been some issues of the levity of the implant and how effective they can be and the health of the surrounding tissue, because it's quite a different tissue in the eyes. One other thing. Yeah, I'll move. On to another way of writing to nuance. I'm not going to go into the details of this, but it's something that would be useful for you all to be aware of. So this is something called optogenetic manipulation of the nerve cell activity. And this is where. So I think last week you've got you had a lecture on neurotransmitters and how things are going between the membrane of a neurone. So this is an example of this, the internal area of the brain of a neurone and the outside. And there's various proteins that are expressed on the membrane of a neurone. So what this was an innovation that was there a few years ago where they implanted, where they expressed a protein that's the ion transmitter. That was when you shine a light on it. This is actually a Dobson, which is something like what's in the eye when you shine a light on it. It then opens this channel and lets various ions through. And using this technique you're able to get a neurone to get excited or to get inhibited. So this is an example where this is kind of an illustration. You've got these blue, they're shining a blue light at different points in time, and every time there's a blue light you get, you get an action potential. And then if you use the other kind of hyper polarising protein you can get, like when you apply a different kind of the colour of light, you can even get suppression. Of. Firing in neurones. So this is a general strategy where you can use the light to activate neurones either in the brain. And actually this is something that is. Being tried out even in the eye. So trying to rather than putting in electrical activity, which is kind of which damages the tissue as well. They're trying to put in a a chip that then just transmits a light pattern onto it. I'm so not going. To go into that, but I'm just going to move on to the next part, which is about controlling abnormal activity in the brain. And this is where. So in general, when you have a normal activity, the most common method is to try and use prescription drugs to control abnormal activity or anything except like something invasive. So these methods that I'm going to talk about are usually only considered with all the other methods being targeted. No, we're going to show this slide, which is not being used, but hopefully not being used anymore. But, you know, something like in the 1930s where I used electroconvulsive therapy, the reason I put this up is this is kind of something maybe that is popular. You might have seen movies doing this or heard about something like this where they put a large current between the between across the brain, which is just causing it is the large electrical stimulus that is affecting the electrical activity in the brain. And that then causes changes in the in the neural structure. And that was used. It induces a seizure. And the idea was that it would then help relieve symptoms of mental illness. So it's highly controversial and there's like severe side effects. So, you know, it's been covered in popular media quite, quite a lot. So I'm sure you can find more information about that. But it's something that is a historically used technique, but it's not no longer used. But I thought it's useful to just talk about things that are not being used as well. So it's something that's actually much more effective is and currently used a lot. It's deep brain stimulation. So this is something where you've got electrodes that are implanted into the brains of an example of you've got a bilateral implant into two parts. And it's the common targets include the dynamic nucleus, which is around there within the brain of the Globus paladins. That's also another structure. Both are within the stratum of the brain. So this is so these are implanted. You can see these there's like three little points there. Those are the electrode sites. And this is then goes into something like a pacemaker that's placed somewhere in the body, which then can be recharged and so on. And that's delivering pulses periodically. I'm just going to show you a video. Of how. This can be quite effective. I hope this works. So this is a subject with deep brain stimulation on and off. So you can see that. Yeah. They just can do some. Tasks or. They have this huge tremor that they. So you can see it's really effective at alleviating some of the symptoms. This is a this is a subject with Parkinson's disease. Another huge success story. To be honest, I don't think we actually we do know a little bit about how it works, but some of it is a bit of a mystery. It just works. So that's kind of there's quite a lot of research going into how how it's being used and how they can improve the design of it right now. So yeah, so one of the other things about debate simulation before I end the lecture is that it is I think coincidentally it has been doing some research going into how it might be useful in chronic pain or. In. Depression and so on. So there's some trials happening in trying to use it in other mental health or other issues, but I think these are just kind of coincidental where somebody with an implant might show an elevation of other symptoms. And so they're exploring these possibilities. It wouldn't be implanted in a subject unless it's the last it's kind of like the last choice because it's quite an invasive technique. So some advantages of using these simulation techniques is that while the methods are used as a last resort, there are some unique advantages. So they can be spatially very specific regions of the brain. So this is pretty clear. With deep brain stimulation, you get to a specific area rather than stimulating the whole area by drugs kind of systemic. So it goes across the whole grain. So there's an exception to this where you can maybe present an L-dopa drug, which is something for Parkinson's, which goes just to open the magic cells, or there's some new techniques where you've got some designer drugs, where you can use some genetics to target specific cell types. But this is something that's kind of being geared up for the future. And the other advantage to this, other than being spatially specific, is that it can be temporarily specific. So you could just turn on the stimulation for some periods of time and run them for short periods. I haven't really covered this, but there are some trials in using magnetic transcranial magnetic stimulation, which is the magnet kind of stimulating and externally. And there's some attempt to at that using that for depression and other disorders. Okay. So that's that's it for the lecture today thank you very much. Invited to take a look at this. Okay. Let me just you know I'm for the course. I guess I'm wondering if it's kind of like it's a very different kind of question. And I think it's very. I didn't recognise. This. Right. My first. Question was, yeah, you know, they looked like that they would use classification so they would use. But I don't think so. I don't. Think that's. It. But I think a lot. Of it because that's kind of where. The question. I've read about it. Yeah. I was wondering. If you think. Different stuff and stuff. Yeah. Yeah. Yeah, I think so. Either it's just people. People look at the number that people because are looking for something better not to excavate. You know. Some people from different parts of the country or. But increasingly critical of the United States is going to get to the point where it looks like you're going to have to talk to people from different parts.