 OK, hello, good afternoon, let's start. So today we're going off road a little bit. We've been talking a lot about the limitations of science when it comes to giving an analysis of the mind. But today I want to do something on the other side and say something about how deeply illuminating science can be in sometimes quite unexpected ways about what's going on with people subjectively. And in particular, to look at some recent analyses of schizophrenia, everyone should have a copy of the essay prompts. Yeah, you all got a copy of the essay prompts. OK, so you can express yourself. You've got quite a long time, it's over a month, right? No, it's just under a month, three weeks, something like that. And we will spend many happy hours looking at what you do. OK, so there's no reading for next time, there's no reading for Thursday. On Thursday, what I will do is it's not really so much a review as to suggest some ways of identifying and thinking about some of the main themes we've been discussing. In particular, this thing about the role of imagination in an understanding of the mind. And the science can't tell you much about an imaginative understanding of the mind. Next week, we move to a different part of the forest altogether. Next week, we move to personal identity. So we make the transition from the big blue book, the Chalmers book, to the small blue book, the Perry book, and we'll be there for two or three weeks. And if you want to go on with the reading, then the reading next is John Locke's of Identity and Diversity, and Williams is the Self in the Future, both in the Perry Collection. The Locke is difficult. It is really wonderful stuff, but I warn you now, it's difficult to read. If you read it and you find, like many before you, that you give up, then you might want to move on to the Self in the Future, which is a lot more accessible. That's a very accessible article. OK? So that's where we are and where we're going. Today, I want to begin by looking at one of the symptoms of schizophrenia, thought, insertion. Patients feel that thoughts have been inserted into their minds. Excuse me a second. Um, usually I like to have pictures from the slides. There are virtually no pictures today, but I hope you'll find that the text that goes up is dramatic enough to hold your attention. Here's one report of a symptom that many schizophrenic patients have is one of the classic symptoms of schizophrenia. A 22-year-old woman had the delusion that thoughts and feelings emanating from her mother's unconscious were being carried in raindrops that fell on her air conditioner. Thoughts and feelings from her mother's unconscious are being carried in raindrops that fell on her air conditioner. When the raindrops hit the air conditioner, they made a noise. And simultaneously, these thoughts and feelings from her mother merged with her own unconscious. This merging had resulted in her own mental illness. Now, sometimes when patients are talking, when psychiatric patients are talking, you say, well, this is just raving. This doesn't make any sense. And this kind of report is not like that. This kind of report, you get again and again across many patients. And they really seem to be doing their best to describe what is happening to them. This is one of the classic first-rank diagnostic symptoms of schizophrenia. Here's a similar report. A 29-year-old housewife said, I look out of the window. And I think the garden looks nice and the grass looks cool. But the thoughts of Amon Andrews come into my mind. Amon Andrews was a particularly cheesy talk show host on TV. There are no other thoughts, only his. She doesn't mean thoughts about Amon Andrews. She means thoughts from the mind of Amon Andrews. He treats my mind like a screen and flashes thoughts onto it, like you flash a picture. And here's a couple of clinicians describing the phenomenon. Patients report that they feel the thoughts which occur in their heads are not actually their own. They are not experienced as thoughts communicated to them. I mean, there's a sense in which getting thoughts from someone else's mind happens the whole time, right? That's what happens in these little chats that I try and tell you my thoughts and you grasp them and then you say, no, that's all wrong that bit. And you try and change my thoughts, right? You tell me the thoughts in your head. That's commonplace. That's not what these patients are describing. It's as if the particular thought, the concrete thought that was in someone else's mind has left that mind and been put into your mind. One of our patients reported physically feeling the alien thoughts as they entered his head and claimed that he would pinpoint the point of entry. So here's a couple of other examples. Thoughts are put into my head like kill God is just like my mind working, but it isn't. They come from this chap, Chris, they are his thoughts. So the question here is what could be happening to you where if you're told that's what's happening to you, you'd say, of course, that's how it feels. And what's the explanation of this phenomenon? How could you possibly explain what's going on here? A 23-year-old female patient reported, I cry, tears roll down my cheeks and I look unhappy, but inside I have a cold anger because they are using me in this way. And it is not me who is unhappy, but they are projecting unhappiness onto my brain. They project upon me laughter for no reason and you have no idea how terrible it is to laugh and look happy and no, it is not your but their reaction. So anyone looking at these reports that you can see it's the same kind of thing and this is replicated across many, many patients. What's going on? What is happening to them? What could be happening that if you were told about it, you'd say, well, that's what was happening to you. Of course, you'd have the experience of alien thoughts being inserted into your mind. This is your question. How can you get at this? I mean, you might say, well, of course, these people have got something wrong with their brains, right? It's just their brains that are making them do that. And of course, there must be something right about that. The brain of a patient must be different to the brain of a regular person. But that wouldn't of itself explain what was going on. Here's the neuropsychiatrist, Chris Frith, say on this topic, he said, look, suppose you're told that some of the dopamine neurons in patients are reliably firing in a strange way, in an irregular way. When they report these symptoms, when they say they're getting the feeling of alien thought insertion. So you might say, look, I've got a correlation here. It's just when the dopamine neurons firing becomes irregular that you can find the patient expressing these symptoms. And Frith says that kind of explanation, he puts it very strongly, is simply not admissible. And his point is, if you're just told that, you still have no idea what's going on. Why is it dopamine neurons that are doing it? Why is it alien thought insertion that's the upshot? You still, if that's all you get, you still don't understand what is going on if you're just told that. I mean, if you were puzzled by this kind of thing and you're saying, well, how come that's happening to these people? You don't get the answer just by being told it's dopamine neurons. What he's really looking for is something functionalist. He wants a box and arrow diagram where you get some story as to what the dopamine neurons are doing in the system. Why should it be that it's the dopamine neurons that are, who's irregular firing brings about this outcome? If you have a functionalist explanation, something in terms of boxes and arrows that tells you what the neurons are doing in the system, well, without that, we wouldn't understand the outcome at all. So just to state, so I want to pause and ask you what you think the explanation of this in a moment, but just to try and state a little bit more abstractly what the symptom is, Descartes clearly thought that when you say, I'm thinking, that's the foundation of all knowledge. It might all be a dream. Maybe the whole physical world is an illusion. Maybe I'm crazy, but still and all, when I get onto one of my own thoughts, I know exactly what is going on. That is the foundation of all knowledge. That is the base certainty. But what these examples show, it seems to me, is that there's some complexity in the notion of you having a thought. And think of what's going on with these patients. They feel that a thought that's been produced by someone else is being put into their mind. So usually when you, at the moment, I mean, you can just try this right now, cast an eye inwards and ask what thought is going through my mind. Well, usually that thought has two characteristics. One is that you made it. And the other is that you can access it. You can look inwards and see that thought. So you made the thing and you look inwards and you can inspect it. You might think of a signature. Like if you think about the notion of someone's signature, well, for it to be that person's signature, that person had to have made it. It's not that they made something like that. It's that they actually physically produced it. And similarly, you usually think, well, if something is going to be my thought, I had to be the one who made it. When Descartes says, I think, Descartes is the one who hammered out that very thought. Like a horseshoe on an anvil, he made the thought. But we also think if it's your thought, if it's a thought in your mind, then it's accessible to you. You look inside and you see that the thought is there. And what these kind of cases seem to show is that these two things can come apart. These patients feel as if thoughts that were forged, thoughts that were hammered out, thoughts that were made by someone else have been pushed into their mind. And when they look inside their mind, they access that thought that was first hammered out by someone else. So in thought insertion, the thought seems not to have been produced by me, but the thought is accessible to me when I introspect, when I look inside my mind. The great psychiatrist, Jasper said, the thoughts, this is a patient of Jasper's, said, the thoughts come at any moment like a gift. I do not dare impart them as if they were my own. Yeah, yes, yes. They're aware of the thoughts. Oh, is she to prove that they exist? Yes. Well, it's an interesting question exactly how this possibility bears in the Kajito. What these patients feel like is that someone else is using their mind as a scratch pad, right? Sorry? That's right. Okay, but how should I put this? If someone else inscribes in your mind, I exist, who is it that they're saying exists? It's the external agent who's asserting their own existence. You look inside your mind, there's the thought, I exist, but it's not talking about you. Okay, so your task is what's the explanation? Well, first of all, let me check. Is it clear what the phenomenon is? Yeah, yep. It's not usually that every, it's not, I think, I don't know of any case where, every thought of the patient has been taken over by someone else, that's not the feeling. As you say in these reports, the patient is reacting, is still thinking, is having their own thoughts. They could surely know that they're having those thoughts about the inserted thoughts, yeah? I mean, I remember watching a video of a, a 29-year-old woman talking about her horrible neighbor, who, he does these terrible things to me. He's put garbage all over my front path, and then sometimes when I'm at a party, he will talk in my brain, and I didn't know people could do that. She was very upset, but it's usually local, people sense that this is, I think one way to think of it is, it's like, well, I don't know if you guys ever know, do tune radios, tuning a radio? Well, sometimes you've got a radio on the right station, and then another station will break in. It's kind of like that. It's a dramatic interruption to normal service. One, two, three, yep. Sometimes there are people they know, sometimes they're completely invented, yeah? There doesn't seem to be a rule about that, yeah? Well, the thought from someone else, the patient finds themselves thinking, kill God, yeah? Right, okay. That thought's in their mind. If they shut their eyes, just looked at what you were thinking right now, they see that, they get that thought going through their head, but it's not their thought. Yeah, you could be doing both things, yeah? But you might not be, you might just be looking inwards, yeah, yeah? Yep, yep, yeah. Yes, very good. It's an interesting distinction. The thoughts are being controlled, that could happen in a quite innocent way, right? I mean, that's what happens in these little charts, right? In any little chart, really, you try and control the other person's attention. You say, listen to me, listen to what I'm talking about. You see what I mean? You're trying to do that. It's related to control because control is causation, right? But the causation here is coming in very deep in that it's actually what's generating that particular thought. Do you see what I mean? It's not just that I'm herding the direction or you're herding the direction of my thoughts. You see what I mean? I'm generating all the thoughts and you're trying to make me go in a particular direction. Yeah, that's one thing. But you could think of this as a kind of limit case of control where the thoughts are actually being made by the other person and I don't even get to make them. It's hard to know how to do the arithmetic here. If you see what I mean, I think it's very distressing and disturbing, typically, when it happens. As in some of these reports, yeah. So in that sense, it crowds out other things, yeah. But whether there's a limit to the number of thoughts you can be having at any one time nuts. I don't know what the maths would be. If you see what I mean, I don't know how you do the count. Yeah, one, two. I was going to say, how do you process, is like they're being tricked into thinking that the mind is being infiltrated. How do you trust what you're saying? You can't trust, well, in a sense, you can't trust, I mean, they must be wrong. There's nobody there making the thoughts but them, right? Nobody has that power, yeah. So it's not that you can trust them as to whether someone else is really doing this, right? When the patient complains about her terrible neighbour doing this stuff, no one's suggesting that she should, well, my fault, actually, what she was saying. No, they must be being tricked in that way. But the puzzling thing is, how is the trick being done? Yeah, that's what's really puzzling. If you're at all interested in helping these patients, then that's what you need to understand is how the trick is being done. And if you want to understand how the healthy mind works, this is really central to the functioning of a healthy mind, that you don't do that. So why isn't it more common? You know, how do we manage it? How do we manage to avoid that trick, whatever it is? That's the puzzle, yeah. Oh, okay. Explanations? Good, one, two, yeah. Excessive imagination. Yeah. Yeah. Imagination you typically think of as a kind of free creative play. These people have this force upon them very much against their will. Yeah. How is that happening? Even if you say it's imagination, how could something be seizing control of your imagination like that? Yeah, yeah. Yes. Where did that come from? Yes. Yes, right. That's very interesting. No, there is that phenomenon of, you know, you're walking along and you're, you're sitting in a, I mean, don't do this, but you're sitting in a lecture room and you suddenly think, why don't I set fire to the whole place? And then you think, well, where did that come from? You know, why did I think that? Yeah. I mean, I take it this is not just autobiographical. Yeah, I mean, has to reject it. Yeah. When you get an example like Kill God, you might think about that kind of thing. Yeah. What I wonder about that kind of case is when it's something like the thoughts of Amy and Andrews, you know, there might be quite banal thoughts. It's not really that these are terribly threatening. What's in them, in their content? You know, with Kill God, or if I do have the thought, why don't I set fire to the whole place? You might think, the devil made me do that. He made me think that. You seem to mean the devil puts these thoughts in my head. But in a lot of these cases, the thoughts that people feel inserted are unthreatening in themselves. Amy and Andrews was not a guy who thought threatening thoughts. What is threatening is just the very fact that these things are coming in. Morphic fields, right? Yeah, good, yeah. Yes, right, right. Uh-huh, uh-huh. Uh-huh, yeah. Yeah. If you believe it, it's true, but that could be... Yes. It's hard to know. I mean, the thing that you believe in expanded minds and overlapping minds is dangerously close to exhibiting the symptoms. If you see what I mean. No, I don't mean that about you, I mean. The trouble with that is, it's not so much that it's implausible. It sounds like a repeat of the symptoms. It doesn't really explain it. It just says, yeah, of course our minds can bump into one another like that. You see what I mean? Yeah. Yeah, sorry. Oxytocin? Very good. Yes. That's excellent. That's the kind of thing Frith is looking for when he says, don't just tell me it's dopamine, right? So a first pass would say, don't just tell me it's oxytocin, but you're going further. You're saying, here's what oxytocin does. It has something to do with empathy and feeling bonded to other people. So if it was an imbalance in this, yeah? Then that might explain it. Straight off the top of my head, I think there are two things about that. One is that I think the patients at this stage usually feel highly isolated. They're not feeling particularly empathic at all. So if you thought of it like that, you'd expect that whatever was going on with the oxytocin would be lowering empathy, yeah? But if it's to explain the sense that other people's thoughts are coming right in, you'd expect it to be heightening empathy, yeah? So that seems like it has to do the two things at once, lower and heighten empathy, but there might be other ways you could develop it. Yeah, I mean, that's a good idea, yeah, yep. Yes, right, right. I mean, the old idea of brainwashing was you just keep saying this stuff to people about how great your home country is, yeah, or whatever, you capture the prisoner and you tell them how wrong they were and their past life and so on. And if you just say stuff to people again and again, maybe they eventually believe it, that's the kind of phenomenon you're talking about. So if the voices come in, then you might eventually believe what they're saying, yeah. My impression is that, so far as that kind of thing goes, the picture with patients is all over the place. Some people do take the voices very seriously, the thoughts in their head very seriously. Some people reject them, hate them, you want to be completely distanced from them. So my impression is in these kind of cases is just a very, very picture. But it's an important phenomenon, that kind of brainwashing thing, if that's what you meant. Okay. Yes? Okay, I'm not an expert, but my impression is not. Well, it depends what you mean. It doesn't show usually until late adolescence, yeah? Yes, right, right. Very good. That's a very different kind of explanation to the oxytocin kind of explanation. That's putting it on a very high level and saying in people's psychology, they're building up a sense of self. There are sometimes fractures and then you might split it off and say that's the bad me, if you see, this is the good me, yeah? Oh, and you might externalize it still further. Yeah, that would go down the path to some kind of psychodynamic, kind of Freudian kind of theory, maybe. So yeah, that's exactly the kind of thing, yeah. That would count as an explanation, if that were true. There would be, I think if you were following this track, you would say there are different forms this can take, yeah? You could have different, but you could have multiple personalities. You could have just externalization of these thoughts, the feeling that they're alien, yeah. Okay, I want to share with you what I think is currently the, I mean, these are great ideas. These are big, important traditions of thinking about these things, but I want to share with you the, what is currently a really interesting, I think really interesting theory as to what is going on here. So the start out with just one more symptom, well-known symptom of schizophrenic patients, the sense of possession. I mean, to put it simply, the subject makes mistakes about who's causing their bodily movements. So just as you sit here right now, you can try this right now, if you move your arm, right? Okay, you see your arm move and you ask, there are two questions you can ask. One is how did my arm move? And the other question is who moved it? The person behind you could, after all, seize your arm and make it move just that way, right? But when you move your arm, it's perfectly obvious to you that it was you that moved it. But with patients, patients make mistakes about who's causing their bodily movements. As very common in the case of speech, people say things like, the force moved my lips. I began to speak. The words were made for me. So imagine that, right? You're talking. Now the thing is, as someone said earlier, that's got to be a mistake, right? It's not that someone else is there. The patient themselves is the only person that's implicated in the production of that speech. No one else really is doing it. But that's how it feels. So the ability that you have to know who's generating your bodily movements has been lost by these patients. A 29-year-old shorthand typist described her actions as follows. When I reach my hand for the comb, it is my hand and arm which move and my fingers pick up the pen, but I don't control them. I sit there wanting them to move and they are quite independent. What they do is nothing to do with me. I am just a puppet who is manipulated by cosmic strings. When the strings are pulled, my body moves and I can't prevent it. That's how it feels to the patient. So for the patient, it's like when you did that thing of moving your arm, the patient is moving their arm themselves, but it feels to them as if someone else did that, as if someone else reached in, grabbed, and made that happen. So how is it that you know which actions were performed by you? How do you know which of your bodily actions were performed by you and which weren't? I mean, that's often important, right? If I, I mean, to take an example from last time, if I stand on your toe in a crowded elevator, it's two different situations. If someone pushed me and my body toppled onto your toe, or if I coldly and deliberately saw your toe and went crunch, right? In the one case, I made the action. In the other case, I was pushed and it's perfectly obvious to me which happened. These patients have lost the ability to make that discrimination. So that raises the question, how is it that you're doing it? Do you have some sense organ that lets you do that? Do you make some calculation? How are you doing it? How do you find out what you observe when your arm moves like this might be exactly the same when you do it as when someone else does it? So how are you doing it? How are you making the distinction between the case where you made it? It seems so easy and effortless. But when you stop to ask, how do I know? How am I doing this? It really seems very puzzling. And you know, it always really seems puzzling when you suddenly encounter people who can't do it anymore, who have lost the ability to make that distinction. And then we really want to know what is going wrong there? Yes, yes, that was a patient. Yeah, that was a schizophrenic patient. No, I mean, someone who makes that kind of report, that's pretty bad. Yeah, you're really not in good shape if you're making that kind of report. Of course, I mean, any of us can feel like that, right? I just get pushed about by these people giving me essay prompts and God knows what and making me do this and that. You can feel like that in everyday life, but this is a much more visceral kind of thing. It's the local movement. It's not just that you're a wage slave, if you see what I mean. It's that the actual physical movement is generated by someone else. Oh, yep. Yes, it's like a split brain patient, yeah. It's a little bit like that. Part of what's happening is not under your conscious control, yeah, that's right. But it's pretty high level stuff that is happening, like it's speech, yeah. Yep. Yes, very good. So I generated the thought, move the arm. So since that thought was generated by me, the action was generated by me. Yeah, that's a really interesting idea. There are a couple of things about that. One is it then raises the question, how do I know who generated the thought? Yeah, I mean, in a way, you just pushed it back one. Because that's what's going wrong in these earlier cases, yeah. And these are the same population of patients I'm talking about. They have both things going wrong, yeah. They know when they don't generate the thought. Yeah, but what I mean is, there's a question, how are you doing that? You see what I mean? You're solving the case of action by saying it depends on knowing which thoughts are yours. And that's fine, that's an interesting idea. But it only pushes it back one, because then we have the question, how do you know which thoughts were generated by you? And the other thing is, sometimes that is in the case of this patient, she says, I sit there wanting them to move. So she's generating the thought, I want it to move. But what she feels like is, whether they do move is not up to me, yeah. So she's losing at that stage. Yeah, that is an interesting idea. OK, here's one way of thinking of it. Suppose you start, suppose you just in the back of an envelope start doing a box and arrow diagram for your movements. Well, here's your brain, right? Here's your brain saying, I want to lift my arm, I want to comb my hair, I want to write down a message. So your brain issues a motor instruction, move your arm thus and so. And then that gets translated into a bodily movement that causes a bodily movement. And then you see your arm moving, yeah? All right, that's pretty straightforward, yeah. But so far, when you see, if this is the whole story, that when you see the bodily movement, you have no way of knowing that it was you that generated the motor instruction. And you've got some central monitor back in your brain where your observation of the arm movement goes. Then back at central monitoring, they say, hey, my arm just moved. Who made it move? They have no idea of central monitoring, right? You see that, yeah? So the simplest model you could have to explain what's going on here is, suppose that what happens when your brain issues an instruction to your body to move something, suppose that what happens is that it sends off a copy of that instruction to central monitoring. So you might think of it like a big company with a buying department, right? So you want to purchase some photocopier equipment. So if you go to purchase the photocopier equipment, you send off a copy of that purchase or request to some central monitoring system, yeah? And then when the photocopiers arrive, they say, yeah, we asked for that, right? So if you want to move your arm, then what you can do is not just instruct your arm to move, but mail off a copy of that instruction to central monitoring. You see what I mean? What is central monitoring? Central monitoring is just another part of your brain, right? Yeah? Central monitoring here, it mustn't become a kind of homunculus. It's not that central monitoring is the real you or something, you see what I mean? It's just that all it does is you send off instructions to make the movements here to your body, and then you send off a copy to central monitoring in the business that is called an efferent copy, that copy of the instruction. And then back at central monitoring, they can do lots of stuff with that. They can say, no, that's a really bad idea and try and cancel the action, yeah, or correct the action. So that happens the whole time, right? You start to swear, and then you realize, God, I shouldn't do that, and you bite your tongue halfway through, or you suddenly start to make a remark about Bill, and you think, my God, I don't want to talk about Bill right now. You see what I mean? So you can see that happening because you it's not that you had to wait and see what you said. You see what I mean? Back at central monitoring, they said, no, that's a really bad idea. And they sent something back saying cancel that. Does that make sense? Yeah? This is really very simple. So if it doesn't sound simple, then halt me. Yeah? Now, the thing about this kind of system is that lots and lots of animals have this kind of system in them. This has been known about since about the 1950s. So with your eye movements, it was first found out about, in the case of eye movements, where there was this basic puzzle that if you move your head right now, right? You can try this, right? Then everything on your retina changes, right? So how do you know that what's going on is not that the room is swinging back and forth, whether that's actually you? And if you do that right now, then the room seems completely stable while you're doing that. It doesn't, for a moment, seem like things are rocketed backwards and forwards. But if the whole thing had rocketed backwards and forwards, you'd have been able to tell in a moment. So how are you doing that? How do you know when the change in what's going on in your vision is because of a change that you initiated and rather than being a change that the world made? Well, because your eye movements have got some structure like this, so that you don't just have an instruction to the eye to move, you send off a copy to central monitoring. And then that can cancel the sense of movement. So back at central monitoring, they say, hey, everything shifted to the left. But that's OK. Back at central monitoring, we have a copy of an instruction to the eyes to move to the right. So that's all right. But if, as you did this, somebody moved, if someone stood up as you did this, you'd know immediately. You can factor out which are the changes in vision that you've initiated and which are the changes that someone else has done. And you need to have some system like that to do that kind of thing. There are lots of ingenious experiments with either sewing on animals' eyes backwards and so on, so that it was a fun back in the 1950s, so that all the system goes wrong. And then you can pick up on just what is happening. Some of you look absolutely appalled. I'm not saying you shouldn't be, but a gentler thing is, if you've got a system like that, you can use it to calibrate your own actions. There are experiments with people where you give people lenses to wear, prisms to wear, that shift everything they're seeing, three inches to the left. Now, at first, as you can imagine, when you're using prisms like that, are you going to be accurate in picking things up? No, you're going to be extremely clumsy, right? You're trying to visually guide your action, but nothing is quite what it seems to be. But people actually learn to work with it, to live with these prisms very, very quickly. So what they're doing is they're using a system like this. They're saying, pick up this thing. They send off the instruction. They send off a copy of the instruction to central monitoring. And then back at central monitoring, they say, boy, that didn't work out. Next time you send a motor instruction, try thinking of moving it a bit to the right. You see what I mean? So you can train the system like that. The system can be taught like that. And of course, that's really important for children growing up. Children growing up are changing their body size the whole time. They're really in the position of someone wearing these lenses. They've got to keep recalibrating what they do. In order to get the right results, I mean, that's why children growing up going through a period of very rapid growth are often said to be very, very clumsy and so on. Because your body has changed so much, so fast, that you're just not accurate in getting your hand to where you want it to go. But with a system like this, the thing is teachable. Your motor system can be trained. So suppose something went wrong with that system. Suppose that what happens is you've got a system like that. And suppose that what happens is you send off an instruction to your arm to move. And then your arm moves, and you see your arm moving. But back at central monitoring, they don't have a copy of the instruction to move the arm. How is that going to feel? It will feel like someone else did it, yeah. Or that some force came in and gripped your arm. Yeah. And this theory, this is like that oxytocin theory. This theory has actually been tested really extensively in lots of subtle and unexpected ways. I mean, here's Sarah Jane Blackmore in 2000. She said, although these mechanisms, she means that kind of efferent copy mechanism, have been mainly studied with reference to IVE movements, our ability to monitor and recognize as our own, self-generated limb movements, touch, speech, and thoughts, suggests the existence of a more general mechanism. So she's saying, this doesn't work just for IVE movements. This works for lots of things like limb movements, touch, speech, and thoughts. So OK, this is not too good. But she's basically showing the same picture here. The important thing here is this is basically the same picture that your sensory motor system is sending out a motor command and sending off a copy of that command. Then something predicts what's going to happen as a result of your command. And then there's what the sensory motor system actually does. But the key point here is the word tickliness. I mean, I hope that everyone in the class has had the experience of being tickled. Yes? We all know about tickling. Stop it, stop it, right? But one of the tragedies of life is that you can't tickle yourself, right? You can try this, but it really doesn't work. And then there's a question, why doesn't it work? Why can't you tickle yourself? And it's presumably because of some system like this, that if you know exactly what's going to happen, if your body's predicting exactly what's going to happen, as you try to do the tickle, then your body's predicted exactly what's going to happen, so it's not going to get that tickling being tickled reaction. You see what I mean? And that's the difference between your own action and that and someone else's that you've got this efferent copy being sent off of the motor instruction. But if, like a schizophrenic patient, you have lost that system, so you can't tell anymore which actions are yours and which are someone else's, then should you be able to tickle yourself? Yes, and Sarah Jane Blakemore did this test with her cohort of schizophrenic patients, and she found that they could indeed tickle themselves, a little known benefit of this stressing condition. So there are lots of subtle unexpected predictions of this system. I mean, just to give you a sense, it'll take too long, but I'm happy to talk more about the subtle unexpected ways in which this kind of system works and in which you can test the hypothesis that schizophrenic patients have got a breakdown of this system. Because really, I mean, if you didn't have this kind of model, the thing about tickling would be an absolute mystery, and what it would have to do with thought insertion would be completely baffling. But this system ties such a lot of phenomena together. That's really why I'm highlighting it. It's so simple and it's so powerful, but it's so powerful. So when you get something like this, a report like this, the force moved my lips. I began to speak. The words were weighed for me. What you're getting here is a functionalist explanation. You're getting an account. I mean, that literally is boxes and arrows. And in the end, there's going to be a computational account of what your brain is doing. But because you have that, you're getting some insight into what life is like for the patient. I mean, just try to imagine from the inside what it would be like, not knowing which things, which of your bodily movements were produced by you and which were done by someone else. You'd be shooting in the dark the whole time. And that really basic thing as to what you are in control of and what someone else is doing. OK, so that's the model of possession. That's the explanation. That's the current explanation of the sense of possession. Plain as day? Yeah? Yep? That's right. It's not broken down the whole time. Are they always to go to the side? No, I think these are patients who are showing symptoms at the time. Yeah, I mean, patients don't typically show symptoms the whole time. So for these experiments, you've really got to get patients who are sort of floored, who are displaying symptoms. Yeah. And even then, it won't be everything that's broken down. So this might not have worked, but the extraordinary thing is it did work. OK? OK? So the question is, can you do that for thoughts? Can you explain the feeling of thought insertion using this kind of model? What's your feeling? You remember thought insertion, right? Alien thoughts, yeah? OK. So how would I have to go? I mean, that model's perfectly clear at this point. Yeah? OK. So if you just did this for thinking, then I guess it would be like this. You've got a conscious, you've got a motor instruction to think a conscious thought. You've got a copy of that motor instruction sent off to central monitoring. And then just as you observe your arm and say, hey, was that one of my movements? You can inspect your thought in introspection and say, hey, was that one of mine? And if you've got a copy of that instruction, the central monitoring, they'll say, yes, that was one of our thoughts. And if you don't get that copy, they'll say, no, that was inserted, right? That'd be the model. That's pretty enough. That's what goes on with your thinking. Partly, you're looking at it in introspection. So since you can introspect it, you'll say, in that sense, it's mine that I can see it when I look inside my mind. But the other sense is, I produced it. I made it. And you get that reassurance by having a copy of the instruction at central monitoring. And when I first heard this theory, I thought, that's wonderful. But it's absolutely bonkers. I don't mean that in a technical sense. I mean, I thought, how can that possibly be right? Yep. Oh, yeah. Yes, yes, yes, yes. Right, we make decisions to make movements. Can this happen to another? Yes. Right, without giving the copy. OK, good. Let's just pause that last thing, losing the control. Why is that a problem? I mean, you're addressing the problem without having said what it is. Well, what is the problem? Is that a problem? Yeah, of course. Well, OK, well, OK, so why does this challenge your control of yourself? Right. OK, very good. So where did your question is, where do these motor instructions come from? That's your solution to the problem. Right, OK, just hang on a second. Let's just get what the problem is. The problem is, if this picture is right, it looks like the schizophrenics picture of the world is pretty much correct, actually, because you're not in charge of thinking your thoughts. Something else is making you think all the thoughts you have, wherever these motor instructions are coming from. Right? And some chip in your brain or something that's making you have all these thoughts. I mean, you naturally assume that your conscious thinking is like the CEO. Your conscious thinking is the central executive. You know, I'm in charge. I'm driving this car. I think through what was going to happen. I make the decisions. The conscious thoughts are where the buck stops. The conscious thoughts are the things that really do the driving. But in this picture, they've lost that role. In this picture, your conscious thinking is just an output of some other process. Yeah? That seems completely crazy. Now, you are, in a non-technical sense, right? I mean, how could that be right? And the modification that's being suggested is that both central monitoring, put central monitoring in charge of the motor instructions. Oh, yeah, but conscious thought can't be the output. Yeah, see, there's one thing I really want to emphasize here. You mustn't think of central monitoring as a kind of very powerful homunculus. It is meant to be a relatively low-level brain system. I mean, well, it's relatively high-level. But what I mean is it's very far short of being the complete person. It's just a little system that gets these copies and tries to regulate things. And that's all it does. It's like a gate that you start thinking about Sally and back at central monitoring. They're saying, don't think about Sally. That always makes you upset. You see what I mean? Or you sit down in the morning and you think, today I'm going to write an essay about Nagalon bats. And you're going to try and think about that. So you're trying to direct your thoughts. And then, of course, it's a very familiar experience that you then think about anything. But the thing you were trying to think about, you see what I mean? So we're not very good at regulating our thoughts. But we can do it a bit. We can do it a fair bit. Otherwise, those essays would never get written. You see what I mean? So the idea is that central monitoring is like a flap. It's like a regulatory gate that gives some direction to your thoughts. So that's all it does. So it wouldn't really make sense to put it in charge of the whole show. And if you say, well, no, no, I'm going to put something that involves conscious thinking in charge of the whole show. Well, that's fine. You can put conscious thinking in charge of the whole show. But then you've lost this picture, right? Because you're not explaining where the conscious thoughts come from. And most importantly, you're not explaining how there can be the illusion of inserted thoughts. Because what this model says is this cracks the problem. If this is what's going on, then if what's happening with a patient is that they've lost that efferent copy mailing system, then of course it's going to feel as if their thoughts have been inserted, right? Yeah, there were a couple of other questions about I've forgotten who they were. So if you had your hand up, please come back here. In this process, how do you know? Well, it's patchy. It would be like having a mailing system that works sometimes and didn't work other times. You do have another problem just right there. That's right. But I mean, nobody said this was going to be simple. If you see what I mean, what's astonishing is how much it seems to be you can get out of this very simple model. It's astonishing. It can be pressed as far as it can. But you're absolutely right. Why does it work sometimes and not other times? And why is the external agent identified as one person rather than another? Is another question? So you're right. There are a lot of loose ends here. But this could still be the core of a satisfactory explanation. Sorry, I'm just, yes, carry it. Yes, right, that is another loose end. And this model doesn't explain that. All it says is you're going to have the feeling that your hand was gripped. And the thing is, if just as you're sitting in lecture, someone grips your hand from behind and pushes your arm, then you might say, that's Bill, isn't it? I mean, I'm not saying you would do this, but if you're of a suspicious cast of mind and you're always in the lookout for Bill to do something again, you might say, that's Bill, isn't it? You might naturally fast on to Bill. And these patients, I think, are often doing something like that. And sometimes it is hypothesizing. They're trying to think what the hell is going on. It must be this. They're trying to conjecture as to what must be happening. OK, so one question is, there's a basic problem. Where are these motor instructions coming from? And there's also a question, why would thinking as a process, when you think of thinking, you think, this is the system that's in charge of everything. Why would it be organized like that anyhow? I mean, what is going on? I mean, in vision, you want vision to be organized like that, because you want to distinguish between movements of your own eye, the movements of your eyes that you initiated, and changes in the world. But it's not as if there's some kind of internal mental landscape. And you want to do something with internal vision like that. I mean, that makes no sense. Or you might say, maybe back in the Stone Age, what happened was that one set of cavemen had the ability to insert their thoughts into another tribe. And this was really bad for you if they got at you. So people developed, for good evolutionary reasons, this mechanism to let you tell which thoughts had been inserted and which weren't. I mean, if you've got a mechanism for telling you which thoughts had been inserted and which weren't, you must have it for some adaptive purpose. But that can't be right. I mean, that didn't really happen. Why would you have a mechanism for telling you which thoughts are yours and which thoughts are someone else's? I mean, in this case, the patients suggest that we must have such a mechanism because it can go wrong. But why would we need a mechanism to tell us which thoughts are ours and which thoughts are someone else's? Well, something that lets you have the ability. But why would that be? And I think the most interesting possibility is to keep your thoughts on track. I mean, I said, when you're trying to write an essay, you try and keep your thoughts on track with greater or less success. It's notoriously difficult. But patients go off the charts in really strange ways. Like here, patients are being asked to describe one of four color disks. They've got four color disks in front of them. And they're asked to describe the color of this one. And a regular speaker says something like, the others become blue like the ocean or the sea. I mean, it's a little bit flowery, but it makes perfect sense. Here's a schizophrenic speaker. Kaleen Green, the one without the cream, don't see this color on planes. It looks like moss, boss. There's a kind of weird, free associative characteristic that it has. I mean, people sometimes say to me, I don't really see where you're going with this line of thought, John. But with a schizophrenic speaker showing this kind of disorganized thought, there's no arc to the thought at all. Here's one other example from Eugene Bleyler. With time and years, the individual becomes so lazy in public life that he is not even capable of writing anymore. On such a sheet of paper, one can squeeze many letters if one is careful not to transgress by one square shore. In such fine weather, one should be able to take a walk in the woods. Naturally, not alone, but with a girl. At the end of the year, one always renders the annual accounting. The sun is now in the sky. It is not yet 10 o'clock. So the great thing about this kind of thought is how alien it is to your thought. Your thinking, even when you're at your worst, is not like that. Your thoughts are on track in a way that these guys are just not on track. So what keeps you on track? What keeps your thoughts organized? There must be an answer to that. There must be something that is keeping your thoughts organized. So if you ask, why do you just if you just think about this common sensically, when thoughts pop into your head, I mean, as you were discussing earlier, it can happen that you just think, well, I'm going to set this place on fire and your puzzle as to where that came from. But ordinarily, just as thoughts pop into your head right now, it's your beliefs, your memories, your interests, what seems important to you, that kind of thing is generating the thoughts that bob up in your head. So you could think of it like this. Suppose you've got a task like write an essay or try and remember how it was in my high school or something like that. You've got a task that gives you a kind of rough specification as to what kind of thought you're what you'd like to think. And then you've got a rough specification of what kind of thought you'd like to think. And then the thought is generated. So this might get the effect of what one of the questions was saying of I want my conscious mind to be in charge here of the generation of thoughts. It's not really so much that conscious thoughts are in charge of the generation of thoughts, but your longstanding knowledge of the world, your longstanding concerns, who you love, who you hate, your passions, they're all playing a role in the generation of the specification of what kind of thought you'd like to have. And then the thought is generated. And it can cycle around so that previous thoughts feed into the specification of what kind of thought you'd like to think next. So you specify what kind of thought you'd like to think. And then you send off a copy of that specification to central monitoring. And at central monitoring, they might say, no, no, no, no. You're meant to be thinking about Nagel back up. Don't think that thought, right? You could keep your thoughts on track with a simple little gating mechanism like that. You just say to central monitoring, reject any thought that's not about Nagel and bats. I mean, for example, you see what I mean? So you keep your thoughts on track by sending a copy of the specification out to central monitoring. And then central monitoring can do. Central monitoring isn't very good in humans. I mean, suppose you take the classic example. Don't think about pink elephants. Don't. Right now, suppose you're happy to comply with my question, right? I mean, the one thing that happens is that you immediately start thinking about pink elephants, right? This gating system is not very good in humans. It is one of the puzzling things about thinking is why is it so hard? Why is it so difficult? We don't really have very good mechanisms here. Well, I don't, anyway. Yeah, it just has these notorious things that are difficult for it. But anyway, you have the specification of a thought being generated like that, then the thought, then you can introspect and back at the monitor. So this is a highly practical system, right? This is just trying to keep your thoughts marshaled, keep your thoughts on track. And then, presumably, you've got your task and you can feedback around and say, hey, have I completed the task? Did I complete my thinking of a brilliant, insightful thought about Nagel? So that's thinking. And if you set up a system like that to keep your thoughts on track, it's going to have as a byproduct. If something goes wrong here, if something goes wrong with his mailing system, then you'll have the feeling of thought insertion, okay? So that's what's going on in ordinary thinking. That's what's going on when you're trying to write an essay or try to decide what to do about this or that. Yeah, you've got a system like this working. Okay, that's thinking as a motor process. Happy with that? Okay. Quickly, yep. Yes, that's right. Well, presumably you get to set the road yourself. I mean, well, actually it's not clear. It's not clear. It really is puzzling that because, of course, at some level, you get to decide I'm going to think about Nagel. Yeah? On the other hand, you might find that you just keep thinking about Sally. And you don't want to, but there you do. You see what I mean? It always upsets you. You don't want to or pink elephants. It's hard to give a direct instructions, but we can do it. Otherwise, we would never get anything done. Yeah? You can do it deliberately. It's just thought management is difficult. You know, that's really what PTSD patients, for example, have to cope with is trying to marshal their thoughts, trying to manage their thoughts, yeah? Okay, just quickly I want to draw some implications. So Frith said, now if you think of the dopamine neurons that Frith was talking about, if you say the dopamine neurons are part of your referent copy mailing system, then now you understand what's going on. If you say there's something wrong with the dopamine neurons, then that's the mailing system. Then that gives you an explanation of it's like that oxytocin explanation. You've said it's the dopamine neurons and you've said what they're doing. When Nagel talks about imagination and bats and all that, remember that, Nagel and imagination and bats, Nagel was by no means the first person to talk about imagination and the mind. The great psychiatrist, Yaspers, famously said, we sink ourselves into the psychic situation and understand genetically by empathy how one psychic event emerges from another. And then he said, well, in contrast to imaginative understanding of someone else, we have the purely causal understanding. Not actually going to, we might talk about that more at some other point, but what is happening in a lot of psychiatry is that, I spent a lot of time in this case because I think it's philosophically just very, very interesting and I think it's just generally very interesting what is going to think about the explanation of ordinary thinking. But there's another thing that happens with patients which is patients get, this is related to delusional mood. Patients say things like, something is going on. Do tell me what on earth is going on. Patients feel uncanny and that there is something suspicious afoot. Everything gets a new meaning. Something seems in the air, which the patient cannot account for, a distrustful, uncomfortable, uncanny tension. Patients obviously suffer terribly under it and to reach some definite idea at least is like being relieved from some enormous burden. So you look around the room, you don't know what is happening but something is going on. There's a famous case of a patient who looked at a row of empty marble tables in a cafe and became convinced that the world was coming to an end. Now, Kapoor has, blessed it, has suggested that one thing that one dopamine system, that this is a different dopamine system does is it drives salience, it drives the grabbing of attention by events out there. So sometimes when you look around the room, the dopamine, the mesolumic dopamine system will fire up and say, hey, that's important. Look what's happening there and direct your attention somewhere. So a way to think of it is, it's like the violins in a soundtrack. I mean, the music on a movie soundtrack, it is queuing you in the system as to, is this a boring scene? Is this an interesting scene? What's going on? It's grabbing your attention. Now, the physiological analysis here of these patients who are in this delusional mood is their soundtrack has gone into overdrive. Life for them is, if you imagine watching a movie where one of these movies where it starts out with a camera just panning up and down a suburban street, people taking out the garbage, people washing their cars, very peaceful scene. And then suddenly the soundtrack goes into overdrive, very loud, high staccato violins. And you're in the edge of your seat, thinking, what the hell, what's going on? What's happening? Then life for the patient is like that. They're looking at, for example, a row of empty marble tables in a cafe, but their internal soundtrack is going into overdrive and you just, for relief, get some definite idea as to what this means. Now, Nagel made a very sharp contrast between the level of imaginative understanding and the level of scientific understanding. This was his key idea, it seems to me, we're completely unequipped to think about the subjective character of experience without relying on imagination. And then he said, if I try and imagine what it's like for the bat to be a bat, then I'm restricted to the resources of my own mind and those resources are inadequate to the task. Now, the point there is to make a very sharp distinction between scientific understanding of the bat and imaginative understanding of the bat and to say that the scientific understanding gives you nothing to contribute to your imaginative understanding of the bat. But what I think is going on in a lot of psychiatry and neuropsychology generally, is that what you're getting identified for you are particular circuits in the brain. So when people talk about schizophrenic patients as, and say, these people are just crazy, these people are bunkers, what you mean is, don't even bother trying to have an imaginative or empathetic understanding of them. You can't do it, you can't relate to such a person. But what this kind of analysis in terms of circuits in the brain that are being caused by the environment or by genetic weaknesses to malfunction is that you can expand your imaginative understanding. If you have a patient who's giving these reports I gave at the start, these reports of inserted thoughts, and you say, well, just imaginatively understand what's going on with that patient. Anyone's natural reaction is, but these people are crazy. This is just insane. I can't make anything of it. But then when you get a very fine-grained analysis of where the physiology is going wrong, what the physiology is doing, you get the ability to imagine life from the patient's perspective, or as in that case of salience neurons, you get the ability to imagine what is going on. So it seems to me that it's not right to think of science as completely powerless to illuminate our understanding of one another imaginatively. It seems to me that even in extreme cases, science can really illuminate your capacity for imaginative understanding of other people. So that was meant to be a way of giving some credit to the scientific analysis of the mind. Next, I will do a more general review of what we've done so far. Okay, thanks.