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Nothing like working with your kids at 9:00 in the morning. Can you hear me up the back there? Is it being amplified? Okay. Thank you. So in the last lecture, I tried to help you understand convey to explain to myself that the input to the brain from the senses is this array of signals carried by nerve cells that represent something about the outside world. But that array of signals coming in through the sensory nerves is carried, is constructed over a series of parallel pathways, each of which carries slightly different types of information about the outside world. And that when you get to the cortex, these pathways are then converge and build maps, topographic maps of the sensory periphery. That might be a topographic map of the retina, a topographic map of the skin of the cochlea, etc.. And what I hope that I got for you as well is that those maps are distorted and distorted by the density receptors in different parts of the skin or the eye. For example, those maps can be plastic, although we don't know exactly how much and when. Those maps aren't. Incredibly useful for the in the world, they're very good at representing what's happening on the surface of our body. But if we want to make movements through the world, then we have to do something else. We have to transform those maps into something that is in a coordinated frame, a frame of reference that is behaviourally useful. And the structure of this lecture is to try and take you through some of the folks in the brain. So some of the mechanisms that seem to be at least the starting point of constructing those frames of reference. That. I want to reinforce in this lecture as well. That. Interest in the signals that come through the sensory periphery of the cortex are carried in parallel. These reference frames are also constructed in parallel. We build many different reference frames at the same time in the brain. And what we seem to do is to try to use a particular reference frame when we need to accomplish a task like picking up the phone. In that case, I might use a reference frame which is centred on my hand because that's where the most important part is. So I'm going to take you through those reference frames in the first part of this lecture and then I'm going to use those to provide a framework to try and understand potentially what the mechanisms are for a new or interesting type of nerve nerve circuit in the brain, which is that from mirror neurones, which many, many of you may have heard about. Now, I said to you a couple of lectures, Alexa, ago that these lectures were designed when we were in the pandemic and I was pre-recording them, and I'm struggling to work out the exact pacing, and I discovered that to my course this week. I've what I've done is there's a section of the notes in your slides called Controlling Movements, which I'm going to omit from today's lecture so that we can discuss these more interesting aspects of the brain. I have uploaded a pre-recorded version of that sections about 10 minutes long and it's accessible for me on Moodle. Simon and I'd like you to have a look at it when you have a chance. It won't be necessary for understanding the rest of the content of this lecture, although there are a couple of subtleties that may be apparent. I want to be the performance of the U.S.. Oops. I just want to start the selection with with a recording that I obtained some years ago from sources I can't remember. There's one particular reason which I want to show you this recording, and I'll tell you that at the end of it. But it also introduces to the idea of spatial neglect. Has anyone here heard of spatial neglect before? Anyone? Put your hand up. Oh, in that case, you prepare for your mind to be blown because spatial neglect is one of the most interesting unsolved mysteries of brain function. So this video, this first video should help introduce you to it, and then we'll discuss a little bit about that and the mechanism why that occurs. To be to the point of this of this the first part, you turn to the benefit of the doubt. Frequently you start to look at all of the actual numbers. Positional alignment serve the purpose of this guide to address those with respect to state of excellence. Hold accountable for their support for the weakest example of the various forms of principle over interesting example. Just the complication of that simplistic classification to perform this simple graph, for example, statements that not appear for the first time to read the code, to describe the patient, etc. to make sense of this cause some features of the text, but contextually so. Another way of testing the directive to ask the patient to open page because he came over to Iraq and the patient neglected to use the right side of the page only occasionally some consideration of extended meditation or whether is something in the collection. So this is not behaviour so cheerful coffee perception whether they succeed in school. But of course this difficult because because of excessive force mistakes exceed the features which they create are not really active. However, you can get something set up and use that can be completed in subject. In this case the patient of social with a reserve of the device. Stick with the public, look at the same table for the right side, etc. but for the patient safety and security of the same patient Refugee Convention. These findings, together with the description the patient suggests that medical detectives actually complete the sight of a doctor, at least a photo with ways for them to gather, to look at symmetrically to take. Okay, So I want to share that video, particularly for the verbal description from the patient who has neglected completing those letters on the page. And you can sense from from that description how automatic recollect or her description of the scene is. It's not like she's struggling through all that, something we think that she does perceive through the letters that she is aware of. So this neglect is a really strange and powerful thing. It's very rare. It seems to entail the distortion of a perceived space, and it seems to, although not described particularly here, it can actually occur in more than one of different reference frames. Two of them were were illustrated here, those reference frames, one with the left side of visual space, and the other was the left side of an object. I'll get back to the second one in a minute. And in fact, it's a very complex film. We don't understand it very well. A lot of this work and some of these references in the slides actually come from colleagues at the Institute of Cognitive Neuroscience, which is about 120 metres that way in Queens Square particularly. Don't drive it. It's now unfortunately dead. But a lot of the descriptions came from studying patients with particular types of lesions that we'll get to in a second. This is a very automatic absence of awareness of a part of your visual field or part of an object or part of something. It really suggests that when we construct and model our vision now interpretation of the outside world, we're using different types of representations to do that. And depending on whether or not they are all intact, we have the capacity to access an appropriate one for the task at hand. So as was alluded to in that description, neglect is not simply an absence of awareness, at least not in some simple way of being blind. So, for example, these are two particular examples of how you might test neglect in some patients, and in this case, a person, a patient with a left hemisphere stroke was asked across that sort. I think there should be right hemisphere stroke should actually cross out the components of a navel figure. And they both figure as these figures which have a structure but are actually made up of themselves of little structures, in this case, letters like A's. And so the patient in this case crosses them all the right hand side of the figure. However, when when asked to describe the figure can actually say it's a square or a circle. So there's some strange things going on in this neglect. And similarly, down here on the on the bottom, this is a really lovely experiment from John Driver, where they did something akin to what you see in the in the video. Here's what the patient is asked to to draw. You can see that when asked to draw a right hand side cap, they can reproduce that fairly well. However, when I draw a left hand side, a very poor reproduction of that cat, this is a very interesting way of asking the question Is it part of the left visual field or left hemisphere part of my vision, or is it the left part of an object? Very simple test. Ingenious. To come up with this, ask the patient simply to draw. We draw each of these two identical objects and you can see that in both cases, the left hand side of the object is emitted, not the left hand part of the visual field. So when the object is tilted to the right, it's still the left hand side of the object that is emitted. So neglect is a really strange and worrying for the patient, but intriguing for the experiment. A form of brain damage. And a lot of that research still goes on at the Institute of Neurology and the Institute of Cognitive Neuroscience just down the road. So what does neglect tell us about representation of the world in our brain? As I said, neglect entails an inability to perceive the relationships of things within a particular frame of reference, a part of the visual field upon the object and other ones that I haven't gone through here. Depending on the spread and the focus of the brain, there is the damage the affected frame of reference can be. Egocentric, olive centric, extra or personal. And I hope that you understand each of those terms by the end of this lecture. It suggests that there isn't one single spatial reference frame in which the world is viewed through which we see the world. Instead, there are several, each with their own neural representation, each of which can be deployed depending on the task at hand. And we expect that it should be possible to identify the different frames of reference in the brain. And I should note here, by the way, that most people that show neglect also show other forms of deficits. And the reason for that, generally speaking, is that the brain damage that leads to neglect often spreads to other areas and other functions. So to understand then what we're gonna be talking about, I need to describe to you the different types of frames of reference that we can describe. And this picture summarises them. The two classes are really egocentric for Ellis and egocentric. It's very easy to think about. It's just with respect to the ego, to the body. So, for example, with respect my body, this is my right and this is my left. If I turn around, that's to my right and that's to my left hand to my eye. If I'm looking at you, then that's part of the visual world in my right, part of the world on my left foot. If I look over there, there's two parts of visual world to my right and my left. But who was in the left field now is on the right hand side of my. That's an egocentric form of representation, something that's with respect to my body. It could be my head, my retina. It could also be other forms that discover in a second. The other major class of frames of reference is our essential world centric spaces. So, for example, a GPS gives you coordinates in north, south, east, west. That's a world centre in space. It doesn't depend on the direction I'm facing. Again, if we go right here, this is my right. That's my left I'm facing. So it's my right and it's my left. I'm facing east now, So although east and south have not I worked with and south have not changed in the other central continents, by my figures, in accordance has changed. So the Alessandra coordinates base that will based or even sometimes object based reference frames. These are things that are independent of our and our own body position and depend only on the structure of the world outside. It turns out that that's the most stable representation to use because that doesn't depend on where I'm moving. But we do choose when we describe something in the world to other people, we often choose to use egocentric reference frames. So for example, if I was to describe how to get out of the building, in my case, I got that turn left, turn left again, turn right and then go straight ahead. That's an egocentric description. I could say that third, south and east and slightly north and east again. And that would be another centric description of the same towns. I won't describe much about either centric, but I will just introduce you to the idea that these two things can be distinguished in development and in perception. These really elegant experiments show you that kids originally formed egocentric representations of the world around them and then gradually formed these worlds and centric presentations. So in one in one experiment shown on the top infants, less than one year, I placed in a room and the there's two doors to the room and they're sitting around the table with the experimenter, and their mother appears at one door and then the child is rotated in the room. The room doesn't change. The charges were rotated around the table. And the question is, where does the child expect the mother to peer from from the same door that she was at before or from the door that is on the right hand side of that child, which is the egocentric reference point. And the answer is that at least in young infants, they will prefer to look and to expect that for the mother to come from the right hand or that is the wrong doors. But the one that is on their right hand side is to their egocentric preference example. Now this Dallas centric discapacidad show which World Baseball and its fans develop very slowly. And indeed, some people remain pretty poor even when they get into adulthood, including myself. So this task is illustrative of that. In this task, one would ask a child or a toddler to indicate on the right here what the view from this horse is of this pattern of events here. Is it A, B, C, or D, just have a loophole here. Who thinks it's A, The view of the horse is represented. Okay. What about B? A couple of people see. Few people. They have a few people. The answer is B, with the red, blue and yellow. Proceed from left to right in the view of the horse would be to see it from the left to the right. So that's an that's a reimagining or interpret the world from another point of view. And that's interpreting what from another point of view requires that kind of understanding, because you have to build that representation in a world based audience based on your own context. So these two abilities, egocentric and polycentric reference frames develop at different rates and the egocentric comes first. As I said, I'm not going to talk much about our centric map here because Hugo is actually going to take you through that quite a bit. And I feel like this time when we talk about spatial memory and other aspects of historical function, but the fundamental basis of these other centric maps, these cognitive maps, was actually discovered at UCL by John O'Keefe, whose building is in the anatomy building. I think somewhere in the top drawer. He's still there, still researching. He must be 80 now. He won the Nobel Prize a few years ago, but it hasn't stopped him. And he discovered, as Hugo described to you, that if you recall from the hippocampus of a mouse or a rat wandering around a small wooden box, that the cells in that hippocampus will often fire in a particular location in that particular part of the puzzle. And further experiments show that that the position in the box where they respond to the red dots and the thing, the black things, the trajectory down through that space, red dots, when the neurone fires, we can show you via various manipulations that that representation of space that is embodied in that Nero's place cells activity is actually half a century. I want to spend the next few slides discussing taking through some of the egocentric reference frame that emerged in Cortex. So I've discussed already. One might be an extended work from reference. That is, if you move your eyes from this red dot here. If you look at this on the red dot, Wall-E is on the right hand side of your visual field. If you then transfer your case to the right to the dot on the right one is now on the left hand side of the visual field. That's an eye centred reference frame your eye moves and therefore consequently the position of the objects in the world moves with respect to the centre of gaze and with respect to your retina, even though they haven't changed position in the world. Similarly, this hits into reference frames, things which with respect my head. One example of that is audition sounds that have arrived at the head and are encoded with respect to the direction of the head and the eyes don't move unlike the eyes. And so that reference frame is based. There's other frames of reference, for example, joint frames of reference again for reaching out and grasping this thing. I might like to include the world in the context of the joints that are required to pick up this and handle this environment to tell me that the 20. So a good deal of work in monkeys that are described in humans has shown that these special frames of reference I'm almost certainly built to start to be built in the parietal cortex and prior to the cortex, the visual cortex, back of the brain. Frontal lobes are here, temporal lobes are down here in the proper lobes here, and it's parietal cortex, or at least this bit of the parietal cortex is important in generating representing the spatial reference frames found in the particular part of the parietal cortex around the parietal sulcus. What this image shows here is a summary of many studies looking at neglect with left sided neglect and the density, the colour of the blobs on the side of the brain that represent the probability effectively that damage in that part of the brain would have been associated with neglect. You can see there's very high concentration around this issue prior to Super Square. If you have damage, then you get this form of neglect or some form of neglect. So if we we Inhumans, we find out it's quite difficult to look in the exact new machinery in this part of the brain. But it is possible in monkeys. And it turns out that the newer machinery there in monkeys looks pretty similar to what we might expect from brain imaging in humans or from these lesions. And so we can use that information, these recordings, from a way about having monkeys be trained to do a task. Monkeys can usually perform a much more complicated task. Another animal such as flies or rodents. And we can use those recordings to try and work out what's actually going on in these little brain areas, particularly those around this practice focus area that's received most attention so far is the lateral improperly lip might be coming back with in the next class and even more involved questions about how we decide to make movements. There is some evidence that this area, this little area called LIP, is at least partially involved in starting to generate or start to move as you place an eye based reference frame, which is the kind of topographic map you find in primary visual cortex or in early parts of visual cortex. If we want to change that reference frame into something that is not dependent on when we are looking, we need to start making some changes to the representations that we encode this graph. We actually do a little bit about how why we think that is involved in starting to transform this visual tropic retina topic representation to something that does not depend on the direction of gaze. I mean, explain what these graphs all show first, because you're going to see a field in the next few slides on the x axis. Here is the time, and you can see here it's about this little black bar is about 200 milliseconds or one fifth of a second. There's several different things on the on the y axis here on the top is the position of the animal. Now, he's actually hit fixed in this case, which head is restrained, but he's able to move his eyes around because that is the vertical movements of the eye and the horizontal movements of the eye. The next block shows you, when the stimulus appears, indicates the times when the stimulus is on these little rows. Here are what we call a Rasta plot. And each row is one trial. One time the animal performed this task. And each of those dots is the time of occurrence of a single action potential from a neurone in IP. Now, you may repeat that trial many times in this case, say 15 or 20 times, and you get pretty similar activity across each trial. And so when you average that activity, you get something like this black box below which we call a pair of stimulus time histograms. And the height of that box basically reflects the magnitude of the response of the neurone at that point in time. The number of spikes the neurone is discharging on each trial at that point in time. And so in each of these cases, you can see that just after the stimulus comes on, the neurones respond very short latency about 50 or 80 milliseconds, less than 1/10 of a second after the appearance of stimulus. That's how long it takes the visual information to get from the retina to this part of the brain. Now there's three different trials shown here. These are all recordings from the same nerve cell likely in the monkey doing this task. And the monkey's task is simply to find look at the dot bit like when you're looking at Wall-E. But we're not trying to look. But look at the dot in the letters, the thing that's all the monkeys required to do. In the other two trials, the monkey is required to move the eyes from that dot to another dot that appears. So you can see here, that's what's indicated by the arrow. And you can see that the monkey is successfully doing that because it's horizontal traits which are the sort of the right position, horizontal and position changes just after the stock comes on. And that comes on at this line here. And then a stimulus has been displayed to the animal at a particular location on the TV screen that the dog is also placed on. So in this particular case on the left here, this is what we would expect from a neurone that is simply representing visual stimuli. Responding to a visual stimulus, Stan was fixating flecks of light appears neurone stops responding. Pretty simple. In the second case here, this is a bit more of a funky task in this case. Just before the animal makes nine movement, the stimulus appears on the right hand side. And here you can see what happens is that the neurone still responds to the stimulus that appears when when the eye move to that location. So that that is also consistent perhaps with the with the new on including the position or appearance of an object at a particular position with respect to its iris. However, if you display the stimulus just briefly at its new location here, the same written location with respect to the days before the animal makes the second you actually see that response physically or even though that stimulus was placed in the part of the visual field, it's not normally effective for the mirror. In other words, this new on CTV anticipate. In fact, the animal is about to make a second to this new location in middle place, and it seems to be reaching out to that new location to see if there's anything there already. So these neurones are already starting to disassociate the retina properly. Framework that is encoding really powerful visual cortex is something that doesn't depend on the location of the eye. It's not a complete disassociation to pinpoint. So that's like P going to see patent in this VR trial area eventually further down in the brain, away from the brain. And these neurones are really interesting. Again, this is a monkey performing a task. And again, the task is primarily to maintain fixation on a particular point on the screen. In this case we see the monkey and we can see from the lateral side he's looking at the screen. And his task here is simply to look at this central location. And while he's looking down, a stimulus is presented that comes either towards the mouth. From the top to the bottom, from different locations on the screen or towards the top of the head, again, from different locations on the screen. And what you should see here is that this neurone is very active for the two situations. On the left hand side here, there's lots of activity, lots of spikes, and that's when the object is moving towards the mouth and not when the object is moving towards the forest. If we then change the stimulus slightly. So then what? She has to look up here. You can see that the neurone is too responsive when the animal is when the object is coming towards the mouth, not towards the first. So the activity this neurone seems to depend on whether an object is moving towards the mouth, not on where the animal's viewpoint is. It doesn't matter where abouts in the visual field. It started as long as it was coming towards the end of the forest. So this vector into prior CO areas seems to be standing to construct this representation of objects in the world that depend on that location. With respect to the amount of fibre that's important for feeding. Exactly. And not just the math. If you look at other neurones in other parts of the head that represented. And it's also interesting you report the medial enterprise area rather than the lateral, the medial being close to the middle of the brain. We find exactly what we call rich second frames of reference. That is, that neurones are responsive when animals make a movement towards an object with their arms is also neurones in there that are also responsible to animals. Make seconds. This is a fairly complicated slide. I don't want to take too much away from it, but the point is here that this new one, some of these neurones are active when the animal makes a reaching movement, but not when it makes an eye movement. It seems to be this and other forms of evidence seem to suggest that it was using something about the coordinate space of the joints to actually represent the outside world. There's another area called the anterior inter parietal area, and we're going to discuss that in greater depth in a moment. So to summarise what I've said to you there, there are multiple frames of reference that can be used to represent the world. There's good evidence for the existence of multiple frames of reference in separate circuits in the brain. Spatial neglect means losing a representation of a specific frame of reference for at least one or two, and not all of them. But for that reason we can all. Be aware of objects in a particular coordinate frame. And the other point here is that there's multiple frames of reference represented in parallel different areas in the brain. Simply constructing in parallel with different reference frames. And the consequence of that is that the could have been executed or generated in parallel. When we go to form a task, we can select immediately or quickly which frame of reference we want to use to actually complete that task. We don't have to wait to redo the entire computation again, take the visual image on whatever I want to do with this. I want to reach there. I want to do this instead. That preference frame is already being built. We may not use that reference frame. We may select another reference frame, in which case the question becomes what happens to the new workflow detection of that reference frame that we did not use? And that, I think, is going to be something that should become clear in the next part of the lecture. Is there any questions about that particular component? Okay. So skip over a section, which is basically how the motor cortex controls the muscles. And I could say that there's a there's now a video on your little page, which is through that, and it's five people. What I want to spend. The next lecture discussion is how we control and even understand actions. And I want to take us through some of the really interesting what has happened in this field in the last ten or 15 years. We've talked about the parietal lobe. We skip over what I call the primary motor cortex, which is the actual guts of controlling the muscles. That's in the middle page. We're not going to talk too much about supplementary motor areas, but these are areas which help generate the initial plans for the muscle movements that go to the primary motor cortex. But between these areas, the premotor cortex and the prefrontal cortex seem to take information from the parietal lobe and then distribute them to the motor areas. That's a lot of what we understand about this has been done in the context of a particular term, and I think we can grasp something. Rastafarian or a monkey's case brought a little bit of food. Turns out that the circuits for this simply quite similar in monkeys and humans. The talk shows a schematic of a monkey brain, the bottom of the human brain, the areas of interest in the monkey brain of the those around the enterprise, those focus in particular the anterior area is a little area called F5 and also F1 in humans. The same areas exist. We know that from the anatomy and from the tracing of connections between pathways. We don't really know exactly how signals get from one area to another. So we're going to use the monkey to try and understand a bit of that, but also look at some of the human pathways. So this here is in the same kind of way. Actually, the previous slides, a description of several neurones in anterior into parietal area during grasping, which I find is absolutely fascinating because there's one particular type of neurone here in the bottom right, which seems to be important in taking that sensory information that's coming up from the sensory periphery through the visual cortex and starting to transform that into something that's useful for motor movements. So this slide shows three separate neurones in each row and for each new on the three different paths. The different tasks. The different columns are to perform a manipulation in light that is to create something more certain. See it? The second one is to reach out and grasp that thing in the dark. So I can't see there is no visual information. And the third thing is just to look at the object and not reach the ground. So the neurone on the top here shows falling rates like we might expect from a visual appeal if it's near or it's active. When the animals manipulate an object in the light, it's also active when it sees the object to manipulate it, but it's not at all active when it makes the muscle movements, they can't see the object. On the other hand, this middle row here is a kind of demand that we might expect to be important in controlling the movements that we're about to make so that no one is active. When we reach out across the line and is active when we reach out and draw something, the dog can see it, but it's not at all active. When we just look at the optics. So it's active during the past, but when you look at it, so these visual motor neurones, it's a kind of classic distinction between sensory input and motor. And for the third part of neurone there, which we'll call a visual motor neurone, combines these two features. These neurones again are active during the regrouping task in the light. These neurones are also active when the animals cannot see the objects and they're also active when they see it, but don't perform the movement. So they have both sensory input seen in the visual only component and motor inputs in the motor and components. And they seem to combine, they seem to be able to combine these two forms into one neurone. And these kinds of neurones, these visual motor neurones can be found in different parts of the brain. The most prominent in the kind of cortex, the frontal cortex. And they are, we think, a very important interface between sensory information. They combine these two things. As we'll discover in the next lecture, You want to combine these two things to make the interesting contributions to defining about what we want to do. So this is the kind of neurones you find in the final area. You actually find is also further up the chain area. Fine. We'll get to that in a moment. These neurones that can be quite selective for the further features of the task. So this is recording from one neurone in this case, and this is a visual motor neurone that is a neurone that you can see both the visual component and motor in front of the task. In this case you can see that just in the visual component alone that the neurones are responsive. This is. This is during the top three. This is the actual during the top when they can see and make the movement. You can see that these neurones are active for particular configurations of grasp and not others. If in addition you look at the visual component alone, that is in the absence of the tons you see, these neurones are also selected for particular objects. How many of you have heard of the concept of affordable? Performance is a really interesting thing. When we design objects, the objects that work, the ones that we want to use for those are for particular actions. The chairs are for the ideas to be. I don't do that with. That means phone too, for the idea of picking them up and scrolling through them. That is the very particular structure. Those objects seems to promote the execution of particular motor planner. Unfortunately. They forward those. Actions. Maybe these neurones are part of that kind of affordances, because when these neurones which are helping, which have both sensory input and motor output, are actually representing particular types of objects, people, okay, So perhaps they help us not to generate the plants when we see that object. One of the plants that I might execute if God wants, but I might not execute one of the plants, I might get a clue that that would afford that particular action. Indeed, if you look at human cortex now rather than monkey cortex, you look at it from signals rather than single unit recordings. You also see a good deal of evidence for the presence of areas that are effectively related to performance. These are the responses or MRI responses in human cortex to observed axons in the top row. Here is when one observes actions without associated objects, and the bottom is when objects are present with chewing, grasping and kicking. Again, this is a person sitting in a scanner and not actually performing his actions that is viewing the action. We think maybe when they're viewing these actions, maybe they're kind of replaying them in their head as well. Or maybe they're viewing them also for to start to build their idea of a particular course of action. And you see from these slides here, but I want you to take away mainly is that there's a substantial amount of activity not only in motor cortex, but also in provider cortex consistent with what we see in the monkeys that when they're looking at particular objects, neurones are active so that those objects may afford particular actions. Similarly, if you just look at the particular example of tools, if they present a hammer to someone sitting in a scanner as opposed to a house or other objects, they would do not forward actions. You find that in prior to Cortex as well as in premotor cortex, this area equivalent to the monkey even at five feet, gets a standard manner of activity. Again, these parietal and motor cortical region seem to be responsive when you're viewing objects that are full potential for action. This experiment I find really beautiful. You've heard about transcranial magnetic stimulation. That's the idea where you put a magnetic pulse outside to stimulate a little bit to the cortex. When you do that, you activate the neurones, the electrical, the cortex. You can choose the pulse and intensity that which doesn't overtly cause an action, but you can measure the activity of muscles in the relevant part of the body. For example, in the hand. And that's what's going on here. These will pass through the amplitude of the muscle movement recorded during stimulation of the cortex. And these measurements are made. What people are feeling for different objects. These are right handed subjects. In one case of viewing a cup with the left hand of one face, right hand to the other cases. Left and right. Broken handles. And what you should see here is that the bar is much higher when the cops are right handed. When their visual object affords particular action. Grasping with the right hand activity, motor cortex seems to be potentiated by viewing this object consistent again with the from right results because cool and consistent again with the work and try to poaching monkeys. So this brings me on then the mirror neurones. How many people have heard of Mira Nair? One of the few who you might know. And if you've read the if you read the Sylvia Hazily speaking, if you read the review that I've included in your reading, you'll understand a lot more about them. Their neurones have gained particular notoriety because they may, they are hypothesised to be a source of understanding the actions of others and perhaps even the higher cognitive social events like empathy. These are circuits to be active when viewing an object for viewing someone doing something as opposed to actually doing it yourself as well as when you're doing so. So these are neurones originally that were discovered. The reason I've talked to you about this search for grasping is that these neurones were discovered by Richard Lockie and colleagues when they were trying to understand these brain circuits across that recording from monkeys. And they noticed that and trained the monkeys to reach out and collect food objects. I wanted to know what was happening during the different phases of movement and plenty of movement. They're reporting from the pool area of the prefrontal cortex called a client. And they notice that a certain fraction of neurones consistently seem to fire, not when the animal, not just when the animal restarting something, but when the experimenter was actually moving or reaching out or grabbing that. And so. So in the writing of the classroom, one of the first neurones that they discovered the classical mirror neurones. So these neurones are active when an animal is reaching out and grasping an object that's shown here. They're also active when the experimenter is reaching out and grasping the object that's shown here. Some of these new ones, it turns out, with finer investigations, were active in particular cases when the animal when the object was available to the animal's reach and when it was not available within the animals, when it's within the animal's reach, that's a very personal space that the space around you when it's not within the reach of the expert personal space. The space is beyond that. You can see here that some neurones seem to respond when actions are performed outside of personal space and other neurones respond when it's in the very personal space. Yeah. So the idea here is that these neurones are responsive to when both an animal is making an action and when the animal is viewing the action. So that's where the idea of mirror neurones comes up in mirroring responsive when you're viewing something as if you were generating that they embody in your brain an interpretation of the action potentially that took place or the accident that person is performing. That might be important. For example, imitation, learning, fine imitation like children do. If you perform an action should take it and learn how to perform that action. However, monkeys don't really live by invitation, so weather is certainly a problem with monkeys. Another question Immigration could also be important for trying to predict what someone else is going to do. If I see someone reaching out for an object and predicting that they're going to be taking an object, I'll be able to understand the potential intentions of the other person. That's the idea of the founding at five. Why? I wanted to introduce you to them in the context of this pathways that you should be clear to by now that they're not just on an incline. They're also found an intuitive triangle area. They also find another part of the brain. So there seems to be a whole network of neurones that seem to be providing not just the actions that we are making, but when we just view those actions will result in a positive step forward. These circuits are collectively known as potentially very neurone circuits and they are thought to be in some context important for things like embodiment and empathy. I do want to make clear, though, that there's there's a lot of controversy. ACLU review makes clear as well. There's a lot of controversy about the role of these neurones in these functions. I don't think there's any controversy about the presence of these neurones. What is of interest and what is of concern is whether these neurones are actually representing what another person is doing with these neurones, basically generating internal but complete the plan of action. As I said to you before, we provide different spatial reference findings in parallel in our brains, we choose which spatial reference frame we're going to use when we execute a particular action. The implication of having multiple parallel reference frames, not all of which are used, is that many. Action plans are made and never executed and never whenever aware of. It's a mirror neurone that for a neurone that is actually representing the actions of others. Or is it a neurone that's representing an on executed plans that we are protecting. Which. Afforded. To us. And that's the central question that still exists in the mirror neurone. Which are these neurones effectively anonymous, or are they there to help us interpret the actions of others or not? And these of course are not there to speak of things they could well be that they, for example, evolved or arose simply to provide clues and execute plans that are co-opted to then try and provide an interpretation understanding of others actions. So I really suggest that you do read Sylvia's article. She's a leader in the field. And at this stage, I will leave you with those with one dichotomy. That's the dichotomy that exists in the field with the laity who discovered these very new ones originally. His group of sceptics were neurones. He's his interpretation, as if this mirror mechanism is fundamental to understanding actions and intentions, then the classical view to the motor system has only a role in generation and by implication the central system has any role in sensation, have to be rejected and replaced by the view that motor system is also one of the major players in cognitive functions. The motor system helps us embody the actions that we view around us. The contract. The contract view is that from Hitchcock and colleagues, he spoke with the language specialists very prominent in the field, and he would state that a null hypothesis is in this area. A five is fundamentally a motor area that is capable of supporting sensory motor associations that are relevant to action selection. As I said before, one of these areas that is involved in generative frames of reference potential, the motor plans that we can execute this selection. So encourage you to read those things and we'll leave that idea of whether or not we're going to contribute fundamentally provision for thanks and how good they can click. Click, click, click here to read more effective. Problems. With you. Take me back to the current context in which you can contribute to that. I could take some time to. Come up with something specifically at the control. Group. That's one of the things that we suspect virtually all. Of the. Idea. But I don't think to. Make the point that medical technicians and. An important part of. The process. Of critical thinking about this is something that even. When I'm writing. The basic hypothesis. Is that there's a lot of activity. Quickly. Actually get. Effective. So it just doesn't make any difference whether. Or not the significant. Activity in this market. Commercial activity. But you might find indications of. What it looks like. It's going to. Be very difficult to keep. Up with. The idea. That an activity. By. Virtue of that are active but actually taking place. I see. Okay. Thank you for taking my question, please. Okay. I guess it's like if you read the study as well, but just. The active when it's objects moving towards the mouse. That's what I'm trying to say, but only when they're moving ahead of the target. So it's much more different from anything. Yeah, it's so interesting. Question Is there any. More than what is it. Going to take that we know that we know psychologically, that whole thing for. Actions. Whether that specific you know, whether specific structure can afford to do for specific. Comparisons as any work is done in the executive there? But it's a good question. I don't think it's coming back. But I don't know. But with all the time it takes to do something like this happens, but it seems to be generated, they're more expensive. But again, we recognise that. People. Keep working on. It could be difficult to predict what's going to happen in Texas because that's not something that's going to come to grips with the fact that people are killed by. In particular for the focus groups which are protected in the construction of the company as well as collaborations. |