WEBVTT 00:00:03.497 --> 00:00:10.477 This is the Convergent Science Network podcast. Leading researchers in the domain 00:00:10.477 --> 00:00:16.777 of neuroscience, brain theory and technology are interviewed by Paul Verschure and Tony Prescott. 00:00:26.017 --> 00:00:28.957 Hello this is tony prescott for the 00:00:28.957 --> 00:00:36.197 conversion science podcast series at barcelona summer school 2013 and i'm here 00:00:36.197 --> 00:00:40.557 with paul verschur who is the chair of the summer school but also this morning 00:00:40.557 --> 00:00:45.197 speaker where he was talking about consciousness and the machine and i'm also 00:00:45.197 --> 00:00:48.457 joined by Tim Pearce, who is on this occasion, 00:00:48.637 --> 00:00:50.877 Tim and I are going to be interviewing Paul. 00:00:51.697 --> 00:00:58.017 So Paul, in this morning's presentation, you began by talking about the importance 00:00:58.017 --> 00:01:00.617 of memory in consciousness. 00:01:01.197 --> 00:01:05.377 But as your talk evolved, memory seemed to go into the background. 00:01:05.517 --> 00:01:09.397 But let's begin with that and say how much of 00:01:09.397 --> 00:01:12.197 what we are now and what we're aware of when we think of 00:01:12.197 --> 00:01:14.897 ourselves is to do with our past history and how does it 00:01:14.897 --> 00:01:17.897 affect us right well so the 00:01:17.897 --> 00:01:20.657 idea would be there that if we think 00:01:20.657 --> 00:01:24.217 about the conscious content um that 00:01:24.217 --> 00:01:27.537 we might experience or the way we experience our 00:01:27.537 --> 00:01:31.397 interaction with the world this is very much predicated upon our 00:01:31.397 --> 00:01:34.397 memory of the past and it's also an idea of a 00:01:34.397 --> 00:01:37.217 book by uh by jerry edelman that he wrote in 00:01:37.217 --> 00:01:40.177 the late 80s called the remembered word present 00:01:40.177 --> 00:01:42.897 and actually at the time I wrote a 00:01:42.897 --> 00:01:48.137 review of this book because this also this book was about Edelman's theory of 00:01:48.137 --> 00:01:53.637 consciousness and even though there were a lot of really interesting and rich 00:01:53.637 --> 00:01:58.157 ideas in there I was still left after reading this book as with a lot of the 00:01:58.157 --> 00:02:00.317 literature I saw at the time about consciousness about well. 00:02:01.389 --> 00:02:04.689 Can we at this stage, are we really in a position to say anything meaningful 00:02:04.689 --> 00:02:10.489 about consciousness beyond this very basic observation that the experience of 00:02:10.489 --> 00:02:12.549 present is predicated on our past? 00:02:14.349 --> 00:02:21.249 So the experience of the present is predicated for you on something rather different 00:02:21.249 --> 00:02:22.889 than our memory of the past. 00:02:23.029 --> 00:02:28.569 It's something to do with creating an instantaneous idea of what you call the unified scene. 00:02:28.569 --> 00:02:31.409 And uh for you is 00:02:31.409 --> 00:02:34.489 is is that an adequate description of consciousness or are 00:02:34.489 --> 00:02:39.829 you picking out a particular aspect of consciousness there well traditionally 00:02:39.829 --> 00:02:45.429 so going back to william james um a characterizing feature of consciousness 00:02:45.429 --> 00:02:49.809 was this notion of a unified scene right so that even though we might find ourselves 00:02:49.809 --> 00:02:54.649 in a very confusing ambiguous and unpredictable world In our experience, 00:02:54.709 --> 00:03:01.529 there's always this unitary understanding of the world that we're in. So it's a unified scene. 00:03:01.989 --> 00:03:05.269 And the question then becomes a little bit like, well, okay, 00:03:05.409 --> 00:03:11.109 what is really the purpose of maintaining such a scene from a biological perspective? 00:03:11.109 --> 00:03:13.869 Perspective that doesn't mean that evolution has a purpose but 00:03:13.869 --> 00:03:17.449 it just means well what's the functional role of maintaining such 00:03:17.449 --> 00:03:20.349 a coherent integrated scene of the 00:03:20.349 --> 00:03:23.309 world we find ourselves in and often our interactions with 00:03:23.309 --> 00:03:27.789 this world and i was also then referring there to to the work by bjorn merker 00:03:27.789 --> 00:03:35.569 because bjorn um proposed this this notion that maybe we maintain this this 00:03:35.569 --> 00:03:40.949 integrated scene as a way to counteract uncertainties that we encounter in the world, 00:03:40.969 --> 00:03:45.809 that the unified scene helps us to disambiguate the states of the world. 00:03:45.869 --> 00:03:49.689 For instance, if we, example, burn would use is, okay, you move about in the 00:03:49.689 --> 00:03:54.189 world, your sensors take your eyes, they move in different ways that you cannot 00:03:54.189 --> 00:03:56.649 fully compensate through your psychotic system. 00:03:56.929 --> 00:04:01.429 So now this imposes noise and input signals. And by having a unified scene, 00:04:01.669 --> 00:04:06.029 I can sort of disambiguate and counteract this noise so that I actually can 00:04:06.029 --> 00:04:07.629 have a better understanding of the world I'm in. 00:04:08.489 --> 00:04:12.849 So consciousness is in a way a filter excluding stuff which is perhaps less 00:04:12.849 --> 00:04:17.669 important and bringing in the things which are really pertinent to acting now. 00:04:19.133 --> 00:04:23.753 Well, it depends how you look upon it. So if you look at the literature, 00:04:23.953 --> 00:04:30.833 all in all, you will not find many strong statements about the function of consciousness. 00:04:31.253 --> 00:04:34.793 So you might find statements on, let's say, the correlates of consciousness, 00:04:35.013 --> 00:04:38.873 like people might have found activity in certain parts of the brain and so on. 00:04:39.233 --> 00:04:44.713 And you will find people isolating certain contributing factors. 00:04:44.713 --> 00:04:51.573 And this I have summarized in what I call the grounded and active predictive experience model, 00:04:51.733 --> 00:05:00.013 which means that conscious content or qualia is on the one hand grounded in 00:05:00.013 --> 00:05:02.353 physical existence, right, in embodiment. 00:05:02.353 --> 00:05:08.253 This would be the first axiom that you see expressed in the work by people such as Thomas Metzinger, 00:05:08.493 --> 00:05:14.693 Bud Craig would pertain to that, or also Damasio or Thomas Nagel, 00:05:14.793 --> 00:05:22.493 where the core feature of conscious states is very much organized through notions of self. 00:05:24.173 --> 00:05:30.073 The inactive part is you will find more in the work by people such as Kevin O'Regan, 00:05:31.193 --> 00:05:37.593 O'Regan sorry who would say well qualia the content of conscious states is very 00:05:37.593 --> 00:05:42.213 much defined by our direct sensory motor coupling to the world right so I hold this cup. 00:05:43.373 --> 00:05:48.013 In some sense I'm able to hold this cup and I experience this cup because of 00:05:48.013 --> 00:05:49.873 law like relationships with this 00:05:49.873 --> 00:05:54.973 object and these laws are now defining my qualia, my conscious states. 00:05:55.313 --> 00:06:00.353 Then you would have a predictive component, which goes back to people like Gary Haslow, 00:06:01.133 --> 00:06:05.933 Barcelou, and others, who would emphasize very strongly that it's not only about 00:06:05.933 --> 00:06:10.353 immediate sensor motor coupling, but it's very strongly dependent on your ability 00:06:10.353 --> 00:06:13.593 to predict and simulate the world. So this is a predictive element. 00:06:13.973 --> 00:06:17.693 And then on top of that, we would have theories like friend by Jerry Edelman, 00:06:17.953 --> 00:06:22.713 Giulio Tononi, who would emphasize integration and differentiation which means 00:06:22.713 --> 00:06:25.653 conscious states are very rich, 00:06:25.753 --> 00:06:28.773 they come in many different forms so they're 00:06:28.773 --> 00:06:34.393 highly differentiated from each other but within every scene every specific 00:06:34.393 --> 00:06:39.993 conscious scene is in itself highly integrated and coherent and this then maps 00:06:39.993 --> 00:06:45.513 to a last set of proposals on the neural substrate which emphasize a notion 00:06:45.513 --> 00:06:48.473 of what's called global workspace advanced by 00:06:48.913 --> 00:06:55.753 Barnett-Barrs and further now elaborated by Jean-Pierre Jangeu and Stanislav Dahan. 00:06:56.591 --> 00:07:01.431 Where this notion of integration and differentiation is more mapped onto a neural 00:07:01.431 --> 00:07:08.111 substrate in terms of the ability of neural states to enter a global workspace, 00:07:08.411 --> 00:07:11.731 which would then be the neural substrate of this conscious scene. 00:07:11.731 --> 00:07:13.411 So actually, there are different perspectives on this. 00:07:13.531 --> 00:07:18.431 And one objective I have in my approach is to not necessarily say, 00:07:18.511 --> 00:07:21.451 well, now we have to choose among these different alternatives. 00:07:21.591 --> 00:07:25.471 But I think we actually can find a compromise where we can see that actually 00:07:25.471 --> 00:07:30.091 each of these elements are necessary conditions of conscious states, 00:07:30.171 --> 00:07:30.931 but they're not sufficient. 00:07:31.071 --> 00:07:34.431 There's something missing. So there are certain prerequisites here, 00:07:34.531 --> 00:07:38.251 and quite a few of them are attached to having a brain. 00:07:38.751 --> 00:07:43.191 But in your talk, you also were quite critical of, if you like, 00:07:43.231 --> 00:07:45.931 the search for the neural or brain correlates of consciousness. 00:07:47.051 --> 00:07:52.731 Do you have an issue about levels of explanation here, or what's your concern about that? 00:07:53.591 --> 00:07:58.931 Yeah, so that's a bit the difference you see in approaches of on the one hand, 00:07:58.951 --> 00:08:05.811 Gerald Edelman, who in the late 80s had this idea of, okay, a theory-based research 00:08:05.811 --> 00:08:06.931 program of consciousness, 00:08:07.311 --> 00:08:12.011 also tying it to what he called real-world artifacts or robots, 00:08:12.191 --> 00:08:18.091 versus the approach more advocated by Francis Crick, who coined this notion 00:08:18.091 --> 00:08:19.611 of the neural correlate of consciousness, 00:08:19.971 --> 00:08:25.391 where you would say, well, we don't need a theoretical framework on the basis 00:08:25.391 --> 00:08:26.531 of which we make specific predictions. 00:08:27.331 --> 00:08:32.051 We should basically search for different correlations between functional operationalizations 00:08:32.051 --> 00:08:35.631 of consciousness and neural response patterns to say, 00:08:35.871 --> 00:08:44.091 well, we might find activity in areas X, Y, and Z correlate with varying levels of conscious states. 00:08:45.031 --> 00:08:49.571 So this is the discrepancy. And I feel from a more general methodological perspective, 00:08:49.871 --> 00:08:56.511 the search for correlations, I think, is a very unfortunate way to try to gain 00:08:56.511 --> 00:09:00.411 insight in reality because the universe is filled with correlations and most 00:09:00.411 --> 00:09:02.151 of these aren't very informative. 00:09:02.511 --> 00:09:08.411 So I think science is tied to theory and constrained predictions and validation of prediction. 00:09:08.411 --> 00:09:16.051 But do you think it's possible to have one instantiation, either a physical 00:09:16.051 --> 00:09:20.891 instantiation or a theory that can somehow take into account all of these different 00:09:20.891 --> 00:09:22.891 diverse views of consciousness? 00:09:23.511 --> 00:09:29.891 Yeah, I do. I do. So one thing that I have been developing and tried to show 00:09:29.891 --> 00:09:35.131 this morning is that over the last 20 years or so, I've developed a theory of mind and brain. 00:09:35.651 --> 00:09:38.791 It's called distributed adaptive control. And roughly it says, 00:09:38.891 --> 00:09:43.871 look, the brain can be seen as a layered control structure where we have a reactive component. 00:09:45.204 --> 00:09:48.584 Roughly, we could map this on brainstem and midbrain structures where you have 00:09:48.584 --> 00:09:51.104 strongly predefined behavioral programs. 00:09:51.604 --> 00:09:57.504 Think about the central gray controlling very complex stereotype behaviors in 00:09:57.504 --> 00:09:58.604 a very predefined fashion. 00:10:00.404 --> 00:10:03.924 Then on top of that layer, you have an adaptive layer, as I call it, 00:10:03.984 --> 00:10:07.544 which I see more as a substrate of classical conditioning. 00:10:08.124 --> 00:10:11.644 And essentially, you can see, look at this layer as developing a state space, 00:10:11.804 --> 00:10:15.724 right? It helps you to label the world, to say, well, these are the objects in the world. 00:10:15.804 --> 00:10:19.004 This is the relative importance of these objects to my existence. 00:10:19.644 --> 00:10:22.524 And then parallel to that, you learn the state space of your own actions. 00:10:23.324 --> 00:10:28.424 The next layer is contextual, where you actually use these states now to develop 00:10:28.424 --> 00:10:30.104 plans for action and policies. 00:10:30.744 --> 00:10:35.384 But across these layers of the architecture, you can see columns that on the 00:10:35.384 --> 00:10:40.144 one hand deal with just processing states of the world. We have reflexes that 00:10:40.144 --> 00:10:44.044 pick up, let's say, loud noises. There's a loud noise. You freeze. 00:10:44.324 --> 00:10:51.084 It's a predefined processing system with one component completely focusing on the world. 00:10:51.184 --> 00:10:55.604 But similarly, at these adaptive and contextual layers, we process states of 00:10:55.604 --> 00:10:59.624 the world up to the level of having a map of the city and making predictions where you want to go. 00:11:00.084 --> 00:11:04.064 The next column is pure self. These are all states of self, maybe going from 00:11:04.064 --> 00:11:08.644 your hypothalamus that tells you that, you know, your body has certain deficits 00:11:08.644 --> 00:11:12.224 you have to work on and replenish to self. 00:11:12.895 --> 00:11:15.755 Very abstract notions of, let's say, your professional career, 00:11:15.855 --> 00:11:18.155 sort of the self notion, the self column. 00:11:18.395 --> 00:11:22.015 And the third column is then all about action and interaction, 00:11:22.375 --> 00:11:27.395 motor systems that you can find at spinal cord levels to frontal areas. 00:11:27.475 --> 00:11:32.615 So in this matrix, I think we can disambiguate a lot of neural processing and neural structures. 00:11:32.995 --> 00:11:38.035 So you have levels of self, but to what extent is it really fair to talk about this as consciousness? 00:11:38.035 --> 00:11:40.875 Because um and you look for instance at 00:11:40.875 --> 00:11:43.655 the classic experiments on blind sight and so you 00:11:43.655 --> 00:11:46.935 can get uh the ability to orient 00:11:46.935 --> 00:11:50.075 to visual cues without having any 00:11:50.075 --> 00:11:52.735 consciousness that those visual cues are out 00:11:52.735 --> 00:11:57.475 there and driving your your movements because your visual cortex isn't operating 00:11:57.475 --> 00:12:02.095 properly but your midbrain your visual midbrain is able to detect them so i 00:12:02.095 --> 00:12:06.955 mean isn't that a clear evidence of a dissociation between what we talk about 00:12:06.955 --> 00:12:10.475 generally as consciousness and these lower-level systems you've been discussing. Absolutely. 00:12:10.535 --> 00:12:13.795 So I completely agree with you, and this is also an important point. 00:12:13.855 --> 00:12:19.915 The theory I just sketched out for you very rapidly, distributed depth of control 00:12:19.915 --> 00:12:23.695 in these components has not that much to say on consciousness. 00:12:23.875 --> 00:12:30.695 However, it does pertain rather directly to this GP framework of the grounded 00:12:30.695 --> 00:12:35.195 and active predictive experience model, which is summarized in the current state of the art. 00:12:35.295 --> 00:12:38.755 And what I show there is, for instance, if you emphasize self and embodiment 00:12:38.755 --> 00:12:44.475 as defining qualia, I can show you how it fits in this overall deck theory that 00:12:44.475 --> 00:12:46.355 it's strongly grounded. 00:12:46.495 --> 00:12:50.235 I mean, our knowledge of the world is strongly grounded in our embodiment, 00:12:50.355 --> 00:12:54.435 but it doesn't say anything about whether it's conscious or not. 00:12:54.595 --> 00:12:58.815 It's neutral to that issue. So what I want to show there is the theoretical 00:12:58.815 --> 00:13:03.315 framework, the theory we have, that we have tested the many robots and the many 00:13:03.315 --> 00:13:07.255 theoretical studies and so on, and also in the clinic. 00:13:07.675 --> 00:13:11.675 That theory maps very well on this summary of the state of the art. 00:13:12.495 --> 00:13:15.855 To illustrate and emphasize that I believe the state of the art is essentially 00:13:15.855 --> 00:13:19.955 highlighting necessary features of consciousness and not sufficient ones. 00:13:20.115 --> 00:13:22.655 So there's something missing in this picture, that's exactly the point, 00:13:22.835 --> 00:13:26.195 and it also means there's something missing in the theory as I summarized it 00:13:26.195 --> 00:13:34.235 so far. So in terms of DAC then, it sounds like a good description of what a whole brain is doing. 00:13:34.395 --> 00:13:38.695 I mean, it's almost like a complete description of the different requirements for a brain. 00:13:39.830 --> 00:13:44.570 So if that were the case, how would we define which subsets of that behavior 00:13:44.570 --> 00:13:46.670 may relate to consciousness or not? 00:13:46.770 --> 00:13:49.970 Or is something else required or is it all there? 00:13:50.090 --> 00:13:55.990 If it is, do certain parts of it at different points in time relevant and not 00:13:55.990 --> 00:13:58.310 relevant? What is the relationship? 00:13:59.530 --> 00:14:06.110 Well, so I see this as a transition in your interactions with the world. 00:14:06.110 --> 00:14:10.330 So on the one hand, the deck structure that I just described that also captures 00:14:10.330 --> 00:14:15.110 these key components of the state of the art in consciousness research deals 00:14:15.110 --> 00:14:17.370 essentially with interactions with the physical world. 00:14:17.550 --> 00:14:22.030 And I summarize that in what I call the H4W problem, where you say, 00:14:22.090 --> 00:14:28.150 well, to interact with the world, so to generate action, to know how I interact 00:14:28.150 --> 00:14:31.090 with the world to the age, I have to answer four questions. 00:14:31.090 --> 00:14:36.870 It is why, what are my motivations and goals to act, what are the objects in 00:14:36.870 --> 00:14:41.030 the world that pertain to these goals, where are these objects in the world, 00:14:41.130 --> 00:14:44.870 where am I located in the world, what's the spatial layout of this whole configuration, 00:14:45.290 --> 00:14:47.150 and lastly, it's when, right? 00:14:47.170 --> 00:14:51.450 How do I time and sequence my behavior to be adapted to this world? 00:14:51.570 --> 00:14:57.550 And my claim is, the starting point of the whole story is that this might be 00:14:57.550 --> 00:15:00.330 nice for interactions with the physical world, but it doesn't require consciousness. 00:15:01.650 --> 00:15:06.110 Because interactions with the physical world are often of a fairly unitary character. 00:15:06.370 --> 00:15:10.290 That means you interact with rocks and then dirt and whatever, 00:15:10.570 --> 00:15:13.510 non-agents, right? Dead matter. 00:15:13.650 --> 00:15:18.170 And interaction with dead matter is fairly straightforward. And I think consciousness 00:15:18.170 --> 00:15:19.730 really comes into the story. 00:15:20.998 --> 00:15:24.978 When you start to interact with other agents, that's really the transition point. 00:15:25.038 --> 00:15:32.078 That's a very specific transition point that I think allows us now to hypothesize 00:15:32.078 --> 00:15:34.938 that certain aspects of the theory are incomplete. 00:15:35.758 --> 00:15:40.158 And that if you want those during evolution, very specific aspects of brains 00:15:40.158 --> 00:15:47.558 were invented to really deal with and solve that specific problem of dealing with other agents. 00:15:48.418 --> 00:15:51.238 So dealing with other agents though is is part of 00:15:51.238 --> 00:15:54.518 this uh larger problem so the you identify 00:15:54.518 --> 00:15:57.758 these components that people have suggested are important 00:15:57.758 --> 00:16:01.338 and you say that they're necessary but not sufficient and the 00:16:01.338 --> 00:16:05.158 extra ingredient is that what you're calling the unified scene or is it more 00:16:05.158 --> 00:16:10.318 than that no it's more than that so the extra ingredient so we have to backtrack 00:16:10.318 --> 00:16:15.458 a little bit because the unified scene we know um i mean as a concept it's around 00:16:15.458 --> 00:16:19.698 for a long time okay so there's There's not that much controversy on it. 00:16:21.418 --> 00:16:26.938 We know we can manipulate this scene if we use drugs, for instance, 00:16:27.098 --> 00:16:31.838 like drugs like LSD or ketamine and so on really can lead to changes to this 00:16:31.838 --> 00:16:34.558 unified scene as you experience it. 00:16:34.958 --> 00:16:41.198 And also when I myself was a subject in these experiments on psychosis, 00:16:42.378 --> 00:16:45.838 essentially this is done by giving you ketamine and if you're lucky, 00:16:45.838 --> 00:16:47.178 you get psychotic or unlucky. 00:16:48.278 --> 00:16:51.518 This leads to a very severe distortion of the conscious scene. 00:16:51.618 --> 00:16:54.298 You lose a sense of space and time for instance. 00:16:54.958 --> 00:16:59.238 That means the conscious scene is maintained by a brain and this is what it suggests to me. 00:16:59.938 --> 00:17:06.718 But the other remarkable observation came from the 80s experiments by Libet 00:17:06.718 --> 00:17:11.858 where he shows that the conscious scene essentially is not operating in real time. 00:17:12.298 --> 00:17:17.078 The conscious scene is a very nice well-defined experiments, 00:17:17.598 --> 00:17:21.998 basically he showed the dissociation between brain states that relate to our 00:17:21.998 --> 00:17:26.638 actions and conscious experience, and that the conscious experience is delayed, 00:17:27.338 --> 00:17:31.338 relative to the brain states that relate to actions, suggesting if you want, 00:17:31.398 --> 00:17:34.078 the brain already knows what to do before you experience that. 00:17:34.918 --> 00:17:38.338 So now that led to this strange conundrum, because it means like, 00:17:38.418 --> 00:17:44.698 okay, here we have all this metabolic power and compute power of the brain dedicated 00:17:44.698 --> 00:17:50.578 to building a conscious scene and maintaining it, but it's running behind in time. 00:17:50.678 --> 00:17:53.438 So it's not causing your ongoing behavior. 00:17:53.578 --> 00:17:57.998 And it led some like Dan Dana to say, well, it therefore might be an epiphenomenon. 00:17:57.998 --> 00:18:02.318 Maybe consciousness therefore is not causing and cannot cause behavior. 00:18:02.378 --> 00:18:06.778 And I think this is where our paths start to diverge, where I think people have 00:18:06.778 --> 00:18:08.858 overlooked some important contributions 00:18:08.858 --> 00:18:13.078 that consciousness can make in the control of real-time behavior. 00:18:14.696 --> 00:18:18.096 Could you elaborate a bit more on what you think that unconsciousness is adding? 00:18:18.376 --> 00:18:23.676 Right, exactly. So, well, I think first of H4W, I interact with the world with bricks, right? 00:18:23.736 --> 00:18:27.656 Well, a brick, I can look at it on the basis of its surface features. 00:18:27.716 --> 00:18:31.316 I can make a pretty accurate prediction what it will do, probably nothing. 00:18:31.756 --> 00:18:36.236 So, now imagine that brick is not a brick, but it's an agent, it's SpongeBob. 00:18:36.336 --> 00:18:40.836 And SpongeBob has goals and wishes and intentions and strategies. 00:18:41.656 --> 00:18:49.616 Now have a whole new problem because SpongeBob doesn't show at its surface essentially 00:18:49.616 --> 00:18:51.176 what these internal states are. 00:18:51.296 --> 00:18:57.596 This is a very fundamental problem of estimating the intentional states of others 00:18:57.596 --> 00:19:00.936 that they're not advertised at the outside. 00:19:01.076 --> 00:19:06.616 This is a fundamental problem and also well recognized already since Hume at 00:19:06.616 --> 00:19:09.796 least, the inference of intentional states. 00:19:09.796 --> 00:19:15.356 So what I'm saying, well, during the Cambrian explosion 500 million years ago 00:19:15.356 --> 00:19:21.236 about, I think something really unique happened in evolution that suddenly agents, 00:19:21.596 --> 00:19:28.376 animals found themselves in a world filled with other agents that could predate 00:19:28.376 --> 00:19:34.016 on them or they could predate on and they would have conspecifics maybe in different social structures. 00:19:34.016 --> 00:19:38.816 This is not so clear but now we move from living in a world of bricks of living 00:19:38.816 --> 00:19:41.776 in a world filled with other agents and these agents have hidden states that 00:19:41.776 --> 00:19:48.256 we cannot easily assess and now where consciousness comes in in my mind as the hypothesis, 00:19:48.936 --> 00:19:55.296 it allows you to actually run massive parallel simulations on the world that 00:19:55.296 --> 00:19:59.716 means if I want to successfully exist in a world with other agents I have to 00:19:59.716 --> 00:20:02.756 run simulations on their internal states to make predictions, 00:20:03.436 --> 00:20:06.356 I have to do this in parallel because I have to operate in real time. 00:20:07.136 --> 00:20:11.676 But the problem of parallel operation is, of course, that you have parallel 00:20:11.676 --> 00:20:14.536 control systems that are not necessarily all coherent. 00:20:14.656 --> 00:20:19.536 So they might actually make opposite contradictory decisions. 00:20:20.336 --> 00:20:25.636 So now, being a single agent, I have a big optimization problem because it means, 00:20:25.716 --> 00:20:29.936 well, if I have all these parallel loops performing their own simulations, 00:20:30.056 --> 00:20:33.516 controlling my real-time performance, how do I optimize them? 00:20:33.576 --> 00:20:37.176 How do I know whether I made a mistake or I did it right, and how do I translate 00:20:37.176 --> 00:20:42.816 that singular observation to parallel control loops? That's where the conscious scene comes in. 00:20:42.976 --> 00:20:47.496 So how I see this is, real-time operation is performed by these parallel control 00:20:47.496 --> 00:20:54.536 loops, so I can keep track of my social environment, make predictions on what might occur, now. 00:20:56.080 --> 00:21:00.640 With some delay, I maintain a coherent conscious scene that is really like a 00:21:00.640 --> 00:21:05.800 compressed state where I go from the possible that is pursued in these simulations 00:21:05.800 --> 00:21:11.040 to the actual that is really the collapse across all these simulations of what 00:21:11.040 --> 00:21:13.020 I believe is really out there. 00:21:13.080 --> 00:21:17.120 This is the world in which I operate and work and the world that gives me feedback. 00:21:17.660 --> 00:21:23.180 This is by necessity intentional. I can now make statements on value, 00:21:23.320 --> 00:21:27.920 and they can percolate those value statements, if you want, back into my parallel controller. 00:21:28.160 --> 00:21:31.120 So real-time operation is parallel. 00:21:31.360 --> 00:21:35.600 This automatically leads to a credit assignment problem that I solve by having 00:21:35.600 --> 00:21:38.600 a singular integrated conscious state. 00:21:39.320 --> 00:21:50.100 But it sounds like a good way of explaining interactions. But is there really, 00:21:51.220 --> 00:21:54.040 is it so unique with interactions between agents? 00:21:54.080 --> 00:21:59.300 For instance, any interaction with the world has all sorts of indeterminisms, 00:21:59.300 --> 00:22:01.560 right? That we can't necessarily predict. 00:22:02.380 --> 00:22:06.720 So don't we have to compute all of those? And didn't we have to do all of that, 00:22:06.740 --> 00:22:09.100 say, before the Cambrian explosion or whatever? 00:22:10.520 --> 00:22:15.820 Well, I would claim that... So the most complex organisms, apparently, 00:22:16.120 --> 00:22:20.780 really early Cambrian, before Cambrian, maybe was a worm-like creature. 00:22:21.700 --> 00:22:26.500 So if you are a worm, I would believe that H4W is not a big deal for you. 00:22:26.540 --> 00:22:30.480 You crawl around in the dirt, you follow some gradients, that's it. 00:22:31.860 --> 00:22:35.280 After they came you know suddenly we have these 30 body 00:22:35.280 --> 00:22:38.760 plants that now can define again many 00:22:38.760 --> 00:22:41.680 variations on these body plants defining many different kinds 00:22:41.680 --> 00:22:47.400 of animals that now exist in complex ecological systems i think that's a real 00:22:47.400 --> 00:22:53.220 qualitative change from being the worm in the dirt so so from having a simulation 00:22:53.220 --> 00:22:58.840 in my brain which helps me make predictions about the future so i can make better choices. 00:22:59.140 --> 00:23:04.280 And part of that simulation in my brain is a simulation of other beings, 00:23:04.400 --> 00:23:06.320 including conspecifics. 00:23:06.440 --> 00:23:11.180 And I guess at one point in the simulation I also have a model of myself. 00:23:11.920 --> 00:23:16.620 But does that model of myself somehow have some privileged status that then 00:23:16.620 --> 00:23:20.320 it becomes part of my consciousness in some way? 00:23:21.629 --> 00:23:26.489 Well, yeah, I mean, in some sense, your model of self has access to other sensor 00:23:26.489 --> 00:23:28.049 states than your model of others. 00:23:28.689 --> 00:23:32.909 And so, for instance, you do have direct feedback from your own body, 00:23:32.989 --> 00:23:39.429 from your own organs and so on, that can all feed into some sort of self model. 00:23:39.509 --> 00:23:41.269 So, yes, the self model is definitely privileged. 00:23:41.489 --> 00:23:45.089 And that's why also in the deck architecture, self is really one of the, 00:23:45.109 --> 00:23:48.789 is the central organizing column in this whole system. 00:23:48.789 --> 00:23:52.449 And also believe that indeed for subjective states, in the end, 00:23:52.449 --> 00:23:54.989 it is, of course, a unified scene that tells you how the self, 00:23:55.169 --> 00:23:58.109 the I, is really placed in the world. 00:23:58.429 --> 00:24:02.569 And maybe that self-model is the basis for building models of others, 00:24:02.629 --> 00:24:06.349 particularly in my own species, so I can say, well, if I was that person, 00:24:06.449 --> 00:24:07.569 what would I be doing? Sure. 00:24:07.729 --> 00:24:13.049 No, look, I agree with this. So this is, of course, also a fairly well-recognized 00:24:13.049 --> 00:24:14.649 mechanism of social perception, 00:24:14.909 --> 00:24:21.029 going back to Merleau-Ponty, right, among others, that you interpret states 00:24:21.029 --> 00:24:22.789 of others in terms of self. 00:24:22.969 --> 00:24:26.569 And this is also where I think this whole discussion on the mirror mechanisms 00:24:26.569 --> 00:24:31.949 have become very relevant, but a lot of this can play out at a subconscious level. 00:24:31.949 --> 00:24:38.229 Level so so a lot of people uh try to explain consciousness in terms of cortex right or. 00:24:39.009 --> 00:24:42.929 Thalamaco cortical interactions and loops and presumably 00:24:42.929 --> 00:24:47.649 the cortex came quite a while after this process right of cambrin explosions 00:24:47.649 --> 00:24:52.789 so it's an interesting question do you need a cortex for this or how come they 00:24:52.789 --> 00:24:57.629 didn't kind of occur co-occur at the same time if you if you if you need some 00:24:57.749 --> 00:24:59.449 loops with a cortical structure? 00:25:00.409 --> 00:25:08.469 How do we reconcile these two different very significant developments in brain architecture? Well. 00:25:09.431 --> 00:25:13.951 So this is a good question, but it also raises important issues on brain evolution, right? 00:25:14.071 --> 00:25:18.051 And so you have this traditional McLean notion of a tree on the brain where, 00:25:18.111 --> 00:25:21.691 let's say, first you have, let's say, your lizard brain, and then after a few 00:25:21.691 --> 00:25:25.691 million years, you add a new layer and so on, right? They're like modules that you stack together. 00:25:26.371 --> 00:25:28.791 I'm not sure that's really a reasonable way to think about it. 00:25:28.871 --> 00:25:33.691 And I would believe, actually, we had another beautiful talk here with Stan 00:25:33.691 --> 00:25:36.811 Grillner, who takes the lamprey as his model animal. 00:25:36.811 --> 00:25:42.571 And he basically shows that the lamprey that evolved, emerged very early in 00:25:42.571 --> 00:25:47.711 the Cambrian, so we're talking 500 million years ago, basically has all the 00:25:47.711 --> 00:25:50.831 ingredients of a vertebrate nervous system, right? 00:25:50.891 --> 00:25:53.211 In a minimally a prototypical state. 00:25:53.411 --> 00:25:59.911 So all structures are there. But then I would believe consciousness is a transient memory system. 00:25:59.911 --> 00:26:03.871 This is why I think the thalamocortical system, that depends very much strongly 00:26:03.871 --> 00:26:09.251 on its dynamics, is a very good candidate to at least be part of that substrate. 00:26:09.451 --> 00:26:13.251 But I have absolutely no problems with suggestions like Bjorn Merker, 00:26:13.431 --> 00:26:18.591 who says, well, maybe there are also already structures more focusing on zona 00:26:18.591 --> 00:26:25.011 inserta superior colliculus that already have rudimentary forms of such a transient 00:26:25.011 --> 00:26:29.971 memory system that we might also attribute some minimal conscious states to. 00:26:30.011 --> 00:26:34.171 For me, I don't see a too categorical distinction there. 00:26:34.211 --> 00:26:37.331 The key thing for me is that we're talking about transient memory systems. 00:26:38.091 --> 00:26:43.051 But then doesn't it become a bit strange why the cortex then developed? 00:26:43.291 --> 00:26:48.191 I mean, if these things were sufficient to have these requirements for consciousness? 00:26:48.931 --> 00:26:53.191 Or are there other reasons for cortex that are independent? Well, 00:26:53.191 --> 00:26:57.071 cortex, I look at cortex more as a big memory system. 00:26:57.291 --> 00:27:02.391 So you can think about primary sensory areas with their receptive fields expressing 00:27:02.391 --> 00:27:04.631 a form of memory of states of the world. 00:27:04.791 --> 00:27:06.911 You can think about more frontal areas. 00:27:07.111 --> 00:27:13.311 You might find states that relate more to strategies and monitoring goals and so on. 00:27:13.451 --> 00:27:18.331 So here we have this massive memory system. So I think the contribution of cortex 00:27:18.331 --> 00:27:23.651 is more memory, allowing you sort of more complex representations and so on. 00:27:23.651 --> 00:27:26.851 But as such as an isolated substrate I 00:27:26.851 --> 00:27:29.731 think it won't help you much in being conscious or not 00:27:29.731 --> 00:27:32.711 because I believe that really strongly depends on the 00:27:32.711 --> 00:27:36.751 dynamics you will find between cortical areas and subcortical areas such as 00:27:36.751 --> 00:27:42.351 the thalamus right that in that interaction conscious states would be residing 00:27:42.351 --> 00:27:45.951 and this also would of course be consistent with these the literature that would 00:27:45.951 --> 00:27:52.151 show that different kinds of anesthetics that really modulate states of the thalamus indeed 00:27:52.271 --> 00:27:55.071 directly modulate levels of consciousness. 00:27:55.331 --> 00:28:01.351 So I think it would be naive to localize this too much in cortex. 00:28:01.911 --> 00:28:05.951 And we should never forget that, of course, we're all strongly biased by cortex 00:28:05.951 --> 00:28:08.211 because it's so easy to measure from it relative to other areas. 00:28:11.736 --> 00:28:15.436 So um one of the uh topics 00:28:15.436 --> 00:28:18.836 you touched on at some depth was uh what's uh 00:28:18.836 --> 00:28:22.116 uh been known as ternoni's phi theory of 00:28:22.116 --> 00:28:27.876 uh consciousness which is uh currently fairly popular and that is a theory that 00:28:27.876 --> 00:28:33.356 makes a very specific prediction about uh properties of the brain and how those 00:28:33.356 --> 00:28:36.836 might be linked to consciousness i mean can you quickly summarize the theory 00:28:36.836 --> 00:28:39.956 for us and perhaps say where you see the problems with that are. 00:28:40.416 --> 00:28:45.896 Well, so this integration information theory, which Giulio Tononi also developed 00:28:45.896 --> 00:28:50.896 already working with Jerry Edelman many years ago, essentially tries to give 00:28:50.896 --> 00:28:55.296 a quantification of brain states that pertain to consciousness. 00:28:55.616 --> 00:29:00.016 So the question could be, look, I'm asleep, the brain is in a certain state. 00:29:00.136 --> 00:29:02.436 I'm awake and conscious, and the brain is in another state. 00:29:02.616 --> 00:29:04.936 How can I have a quantification of that difference? 00:29:05.196 --> 00:29:08.496 So it's a neural correlate that we're talking about. Definitely a neural correlate 00:29:08.496 --> 00:29:11.796 version of this. And so it's a neural correlate approach. 00:29:12.016 --> 00:29:15.116 And the measure essentially tells you something about, let's say, 00:29:15.176 --> 00:29:16.756 the variability of neural states. 00:29:16.836 --> 00:29:23.656 Essentially, Julio conceptualizes this as a reflection of the idea of a unified scene. 00:29:23.796 --> 00:29:29.556 A unified scene would be an undividable whole of information, right? 00:29:29.636 --> 00:29:35.136 So that means how can I identify now these indivisible wholes of information 00:29:35.136 --> 00:29:38.036 information, or these partitions of information. 00:29:38.416 --> 00:29:43.536 And your ability to then… the complexity of these partitions would tell you 00:29:43.536 --> 00:29:44.896 something about the conscious state. 00:29:45.236 --> 00:29:50.276 So essentially it's like an entropy measure, you could say, but with some bells 00:29:50.276 --> 00:29:53.676 and whistles added to it, it tells you something about the variability of neural states. 00:29:53.896 --> 00:29:58.096 And then what they have shown, what Julia has shown, I think very nicely, 00:29:58.296 --> 00:30:02.336 is then how that measure indeed correlates in some way with different levels 00:30:02.336 --> 00:30:06.236 of consciousness, such such as sleep, wakefulness, or different perturbations 00:30:06.236 --> 00:30:08.276 of brain states, and so on. 00:30:08.356 --> 00:30:11.276 But of course, the questions are here now have a quantification. 00:30:11.276 --> 00:30:16.236 I mean, it started out as a mutual information measure, and now it has evolved in different forms. 00:30:16.816 --> 00:30:21.116 But in the end, it's an approximation of some entropy. And... 00:30:22.250 --> 00:30:25.190 Um the point is of course yeah but what does 00:30:25.190 --> 00:30:28.050 it really tell me about let's say the function of consciousness in 00:30:28.050 --> 00:30:31.630 this case or what does it really tell me about the underlying uh dynamic 00:30:31.630 --> 00:30:34.470 organization of it that's not so much but is 00:30:34.470 --> 00:30:38.930 it not a nice to have a marker if indeed that is what it could be of course 00:30:38.930 --> 00:30:43.870 but then so to test that what what we have done is we we have looked at other 00:30:43.870 --> 00:30:49.190 markers of brain activity we have looked at neural responses in the macaque 00:30:49.190 --> 00:30:53.690 dorsal premotor Cortex that we have analyzed and published recently, 00:30:53.870 --> 00:30:59.650 a paper with Stefano Ferreira in Rome and Carnie Marcos, his first author in 00:30:59.650 --> 00:31:06.310 Nuren, where we looked at the role of the inter-trial variability in decision-making in the monkey. 00:31:06.470 --> 00:31:11.490 And basically, you can show that the variability between trials is predictive 00:31:11.490 --> 00:31:16.390 of performance if you manipulate, let's say, the certainty of the animal. 00:31:16.390 --> 00:31:21.310 So then we thought, well, here we have a more generic measure of neural variability. 00:31:21.610 --> 00:31:23.150 We know it relates to performance. 00:31:23.530 --> 00:31:28.250 So let's compare this now to what this phi measure would do on the same data. 00:31:29.570 --> 00:31:35.810 So it is unreasonable to believe that the monkey throughout this trial would 00:31:35.810 --> 00:31:40.530 be conscious of these states of its premotor area for the following reason. 00:31:40.530 --> 00:31:46.630 And what you see is that when the stimulus comes on that informs the monkey 00:31:46.630 --> 00:31:53.370 about the kinds of action it has to execute, different action options are active in this area. 00:31:54.290 --> 00:31:57.710 And slowly, through competition, one will be chosen. 00:31:58.690 --> 00:32:01.950 One will be selected. The conscious scene is unitary. 00:32:02.510 --> 00:32:07.230 So that means the plurality of actions that is represented in this area early 00:32:07.230 --> 00:32:11.430 on in the trial cannot be part of your measure of consciousness because that's not the unitary scene. 00:32:12.348 --> 00:32:17.968 So the only part that can possibly be a contribution to the unitary conscious 00:32:17.968 --> 00:32:24.848 scene is once the system has converged to a single response through a competitive process. 00:32:25.208 --> 00:32:29.288 So you would expect, and if I have a measure that is really specific to consciousness, 00:32:29.608 --> 00:32:35.568 then it would tell you nothing about this pre-conscious state in this area where 00:32:35.568 --> 00:32:39.048 you have a plurality of options open because the conscious scene is unitary. 00:32:39.048 --> 00:32:43.048 And it would give you a lot of information when you have the choice made because 00:32:43.048 --> 00:32:46.308 that's when you have the content for a future conscious state. 00:32:46.768 --> 00:32:51.968 However, what we see is that this phi measure basically is exactly the inverse 00:32:51.968 --> 00:32:53.388 of our intertrial variability. 00:32:53.748 --> 00:32:59.108 So that means in this very specific and restricted element example that I only 00:32:59.108 --> 00:33:04.168 used to sort of illustrate a bit the problem, the measure as such indeed tells 00:33:04.168 --> 00:33:06.008 you something about the variability, 00:33:06.168 --> 00:33:11.488 the entropy in a neural response, but it's completely unspecific to a pre-conscious 00:33:11.488 --> 00:33:13.968 or post-conscious or conscious phase, 00:33:14.568 --> 00:33:18.448 because it happily gives you a measure when you have many options open, 00:33:18.588 --> 00:33:21.408 which cannot be part of the conscious scene because it has to be unitary, 00:33:21.588 --> 00:33:24.848 and where you have a single option open, which can be part of a conscious scene. 00:33:24.948 --> 00:33:30.108 So I think the measure is really not sensitive enough to give you specific information on consciousness. 00:33:30.548 --> 00:33:36.188 So this particular measure may have some problems with it, but I think what may be interesting is. 00:33:37.105 --> 00:33:39.745 From the point of view of studying consciousness is at 00:33:39.745 --> 00:33:42.745 least it's a hypothesis about how 00:33:42.745 --> 00:33:48.625 you could measure objectively conscious states in another mind and you can even 00:33:48.625 --> 00:33:53.725 go as far since this information measure and say well let's take minds that 00:33:53.725 --> 00:33:56.705 may not be instantiated in brains they might be instantiated in computers or 00:33:56.705 --> 00:34:02.225 robots and we can apply that measure to those other minds and so So, 00:34:02.225 --> 00:34:05.245 if we could find a measure, maybe IIT isn't the best one, 00:34:05.345 --> 00:34:09.625 but if we could do that, if we could really see a clear marker for which you 00:34:09.625 --> 00:34:12.425 have an objective definition, this would be useful. 00:34:12.625 --> 00:34:16.225 And your own program of building robots would benefit from that. 00:34:16.465 --> 00:34:20.825 I mean, how would you plan to measure consciousness in robots? parts. 00:34:22.365 --> 00:34:28.165 Look, I agree. Of course, if we have tools to quantify our measurements and 00:34:28.165 --> 00:34:31.885 these quantifications are specific to phenomena we want to explain, 00:34:32.005 --> 00:34:33.885 this is key, right? This is essential. 00:34:34.425 --> 00:34:37.225 But it's a little bit like the discussion around the IQ, right? 00:34:37.325 --> 00:34:42.285 I mean, at some point, now we have these IQ tests, we get scores, 00:34:42.485 --> 00:34:44.365 but in the end we don't really know what we're measuring. 00:34:44.605 --> 00:34:47.485 And so this whole issue of specificity, right? 00:34:47.545 --> 00:34:51.925 So if you say, look, I have a measure here of the The variability of neural 00:34:51.925 --> 00:34:59.685 states or the ability of a system to maintain indivisible informational subdomains 00:34:59.685 --> 00:35:01.665 or something of this kind, that's all fine. 00:35:02.505 --> 00:35:05.725 But it's all about the specificity. If you say, look, it's a specific measure 00:35:05.725 --> 00:35:09.225 to consciousness, then you have to show that specificity. 00:35:09.485 --> 00:35:11.845 If it's not specific, of course, it leads to confusion. 00:35:12.105 --> 00:35:16.565 But I do agree with you that it is absolutely essential to develop these kinds 00:35:16.565 --> 00:35:20.485 of measures. And what I expect, though, is that we have to constrain them more 00:35:20.485 --> 00:35:26.765 by at least a theoretical understanding of the substrate that generates conscious state. 00:35:26.885 --> 00:35:31.045 So I would suggest these kinds of measures might be an interesting starting point. 00:35:32.028 --> 00:35:35.468 But maybe we have to make sure we really apply them to the right subsystems, 00:35:35.468 --> 00:35:38.628 as opposed to in a rather indiscriminate fashion to the whole of the brain. 00:35:38.988 --> 00:35:44.008 But just to push on this, your own program of research includes a very ambitious 00:35:44.008 --> 00:35:47.568 target of building a robot with consciousness. 00:35:48.168 --> 00:35:53.408 But unless you're prepared to commit in advance to some particular measure of 00:35:53.408 --> 00:35:55.768 consciousness, how will you know you've succeeded? 00:35:55.768 --> 00:35:59.028 Did and and uh you know without that commitment you 00:35:59.028 --> 00:36:02.508 could easily as you build your robot uh you 00:36:02.508 --> 00:36:05.368 know modify your goals in order to fit where you 00:36:05.368 --> 00:36:08.168 get to and i think this is the risk with with these 00:36:08.168 --> 00:36:12.568 kinds of programs absolutely but the point is i'm committed i think i'm doing 00:36:12.568 --> 00:36:15.668 better than a neural correlate approach because i'm committing myself to very 00:36:15.668 --> 00:36:20.868 specific theoretical constructs so given the theory what i'm saying so i move 00:36:20.868 --> 00:36:25.868 from h4w to h5w because now i have to deal with who, to deal with who, I have to simulate. 00:36:26.288 --> 00:36:31.468 In order to optimize these internal simulations, I must serialize again and 00:36:31.468 --> 00:36:33.268 solve my credit assignment problem. 00:36:33.668 --> 00:36:38.708 So I'm making very specific predictions, and the core of this is all going in 00:36:38.708 --> 00:36:40.728 the direction of conscious states. 00:36:40.848 --> 00:36:47.928 That means my current task description, biased by my self-model, 00:36:48.008 --> 00:36:49.848 resides in a transient memory. 00:36:49.948 --> 00:36:53.888 That means it's not expressed in a structural memory. It's really in a memory 00:36:53.888 --> 00:36:55.988 that is transient in neural activity. 00:36:56.188 --> 00:36:58.368 So it can very flexibly be changed. 00:36:59.028 --> 00:37:00.888 And I believe that we might find possibilities. 00:37:01.672 --> 00:37:06.092 Echoes of this in the thalamocortical system. So that now means that I have to say, 00:37:06.792 --> 00:37:10.452 okay, in my robot, what I expect to see is, one, 00:37:10.552 --> 00:37:13.532 I have an understanding of the task the robot is in, I have an understanding 00:37:13.532 --> 00:37:16.892 of the memories the robot has formed in the past about this task, 00:37:16.992 --> 00:37:21.872 and now I can find echoes of these states in this transient memory system. 00:37:22.072 --> 00:37:25.632 So I think these are very specific predictions that we can address with the 00:37:25.632 --> 00:37:27.692 kinds of quantifications we already have. 00:37:27.692 --> 00:37:31.092 So we can, can we tie you down on this to say that, you know, 00:37:31.092 --> 00:37:37.672 in 10 years you've built your robot and it solves the H5W problem in some way 00:37:37.672 --> 00:37:44.052 that we've agreed is appropriate and similar to perhaps the human H5W problem. 00:37:44.212 --> 00:37:49.112 Then you would make the strong claim that that robot was conscious because it 00:37:49.112 --> 00:37:52.472 had solved that problem in a demonstrable way. Absolutely. 00:37:52.992 --> 00:37:56.472 Yeah. Okay. We'll come back and check out. No, you should. Good. 00:37:57.192 --> 00:38:03.092 Moreover, I will have found corollaries of this also in the human brain. 00:38:03.152 --> 00:38:08.812 Because, for instance, I believe that this transient memory system we're dealing 00:38:08.812 --> 00:38:14.312 with has to also go through very specific update cycles, certain persistence. 00:38:14.412 --> 00:38:18.492 Also, we know now a certain delay with respect to real-time operation. 00:38:18.492 --> 00:38:22.152 So there are very specific testable predictions coming out of this that we can 00:38:22.152 --> 00:38:26.612 then bring back to also humans and other animals. 00:38:26.812 --> 00:38:33.212 So if we had a system like that that was able to compute these possible intentional 00:38:33.212 --> 00:38:37.992 stances and then select one, bind it to the current system, 00:38:38.473 --> 00:38:45.873 uh the present moment um but what uh what would we uh be able to account for 00:38:45.873 --> 00:38:50.373 in terms of going back to the original gate with these different criteria of 00:38:50.373 --> 00:38:52.313 different theories for consciousness. 00:38:53.833 --> 00:38:59.193 Would it be able to kind of account for all of those and include them and if 00:38:59.193 --> 00:39:03.853 so in what way or what features of that system would then uh basically account 00:39:03.853 --> 00:39:06.853 for the different aspects of how people have been thinking about consciousness. 00:39:07.413 --> 00:39:13.093 Well, so my claim is that already in the theory, we are accounting for these elements, right? 00:39:13.153 --> 00:39:18.173 So for instance, we spend a lot of time looking at predictive systems in the 00:39:18.173 --> 00:39:23.193 cerebellum, in the cortex, subcortical areas, also like basal ganglia. 00:39:23.373 --> 00:39:26.913 So you see, prediction occurs in many of these systems. 00:39:27.253 --> 00:39:32.653 Now, this is one of the axioms of this GP model, going back to people like, 00:39:32.713 --> 00:39:37.133 I mentioned earlier, Jerry Haslow, Barcelou, and so on, and also Bjorn Merker, 00:39:37.313 --> 00:39:40.393 that qualia are defined through prediction. 00:39:40.853 --> 00:39:48.393 So prediction is an organizing principle of the whole theory expressed at many 00:39:48.393 --> 00:39:49.353 different levels of organization. 00:39:49.793 --> 00:39:54.153 So this already shows you that to say, well, qualia are prediction is not specific enough. 00:39:54.373 --> 00:39:59.513 It occurs at all these levels. So what I am aiming for is that we can give this 00:39:59.513 --> 00:40:03.453 now more specificity. that we can say, well, actually it is one subset of predictions 00:40:03.453 --> 00:40:08.933 generated by a very specific system that are pertaining to conscious states. 00:40:09.013 --> 00:40:13.493 For instance, it's an open question, do the cerebellum, which is 15 million 00:40:13.493 --> 00:40:16.193 loops in the human brain, 00:40:16.373 --> 00:40:20.893 making up more than 65% of the neural populations of the central nervous system, 00:40:20.973 --> 00:40:25.813 each of these loops is independently generating a prediction all the time, and. 00:40:27.158 --> 00:40:30.778 When predictions are met or not met, dependent on the outcome of that, 00:40:30.818 --> 00:40:32.198 it might generate event triggers. 00:40:33.158 --> 00:40:38.138 Well, right now it's really unclear whether violations of predictions in the 00:40:38.138 --> 00:40:40.978 cerebellum that will be conveyed through the inferior olive, 00:40:41.958 --> 00:40:46.738 the inferior olive, by the way, is again under feedback control by the cerebellum 00:40:46.738 --> 00:40:51.918 on a prediction-based level, do violations of predictions in the cerebellum 00:40:51.918 --> 00:40:54.078 in any way percolate into conscious states? 00:40:54.218 --> 00:40:58.818 I don't think so. So, but now we can try to evaluate that more specifically, 00:40:59.058 --> 00:41:03.798 okay, that we can really delineate a subset of predictions the brain generates 00:41:03.798 --> 00:41:07.778 at many levels of its organization to say, well, it's only this subset that 00:41:07.778 --> 00:41:11.918 in a very specific way gets gated into a conscious scene. 00:41:12.058 --> 00:41:14.978 I do expect very specific gating mechanisms there at work. 00:41:15.278 --> 00:41:18.418 But if it's the cerebellum that's computing all these possibilities, 00:41:18.658 --> 00:41:22.818 and then the fact that when we remove it, we still have a sense of consciousness. 00:41:25.278 --> 00:41:28.398 How do we reconcile those two facts together? 00:41:29.018 --> 00:41:31.858 Well, I think it's important to distinguish levels of consciousness, 00:41:32.098 --> 00:41:39.858 like Steve Lowery has been writing quite a bit on this, that for instance, I can be asleep, 00:41:40.118 --> 00:41:44.498 I can be anesthetized, I can be in coma, I can be minimally conscious, I can be awake and alert. 00:41:44.498 --> 00:41:47.358 These are all different levels of consciousness, right? 00:41:47.558 --> 00:41:52.538 But then orthogonal to that, if you want, you have content of consciousness, right? 00:41:52.578 --> 00:41:55.998 I can be aware of the interview we're having right now. 00:41:56.118 --> 00:42:04.838 I can be fantasizing while talking to you about sailing or other things I could be doing as well. 00:42:05.318 --> 00:42:11.498 So this is content of consciousness. And I see the cerebellum, 00:42:11.518 --> 00:42:16.398 your question is very much pertaining to this content of consciousness issues. 00:42:16.478 --> 00:42:20.138 If you remove a cerebellum, suddenly you might be ataxic, you might have difficulties 00:42:20.138 --> 00:42:24.038 controlling motor, you might have some difficulties with timing issues. 00:42:24.938 --> 00:42:30.598 There are also suggestions about cognitive deficits you might suffer from with cerebellar lesions. 00:42:30.618 --> 00:42:35.158 So these, of course, will all pertain to a change of conscious state because 00:42:35.158 --> 00:42:40.098 suddenly I cannot play tennis anymore. And yes, this will restrict my potential 00:42:40.098 --> 00:42:42.738 space of experiences, but it doesn't 00:42:42.738 --> 00:42:45.478 tell you anything specific about the organization of consciousness. 00:42:46.178 --> 00:42:51.798 But this just sounds like a whole description of behavior and the brain. 00:42:52.038 --> 00:42:57.358 I mean, the fact that this content of consciousness seems to be directly... 00:42:58.594 --> 00:43:01.954 Uh related to just what 00:43:01.954 --> 00:43:05.014 the brain does and no i don't 00:43:05.014 --> 00:43:08.394 think so look it's an architectural theory of 00:43:08.394 --> 00:43:11.634 consciousness and a functional theory absolutely but i mean a lot of the time 00:43:11.634 --> 00:43:17.314 when people are when we think about what it means to be conscious it's the experience 00:43:17.314 --> 00:43:22.394 of standing on the beach and watching the sunset and that unique set of feelings 00:43:22.394 --> 00:43:27.334 that that evokes in you that's That's what we often mean by the experience of consciousness. 00:43:27.694 --> 00:43:32.194 And that's all about content. But we only spend a very small fraction of our 00:43:32.194 --> 00:43:34.514 life standing on the beach looking at the sunset, though. 00:43:35.134 --> 00:43:38.894 But I can be looking at the color of this microphone cover, which is yellow, 00:43:38.934 --> 00:43:43.254 and thinking that reminds me of the sunset on the beach. So it's evoking. 00:43:44.074 --> 00:43:49.414 Memory is not an input channel, right? But it's evoking those feelings in me. 00:43:49.554 --> 00:43:52.334 So it's about feeling. so it's i find it 00:43:52.334 --> 00:43:54.994 hard to separate the the content and the 00:43:54.994 --> 00:43:58.754 vehicle aspects of okay of consciousness in the way you want to do yeah but 00:43:58.754 --> 00:44:03.494 for me so how i see the feeling which for me comes out of this whole self column 00:44:03.494 --> 00:44:09.174 of the of the architecture starting really very low down and really embodiment 00:44:09.174 --> 00:44:13.814 and very primitive sensations to the notion of a career. 00:44:15.854 --> 00:44:18.934 This is the information channel if 00:44:18.934 --> 00:44:21.834 you want that feeds then into the feeling 00:44:21.834 --> 00:44:27.194 aspects of of a conscious state and also it's a strong ground it also grounds 00:44:27.194 --> 00:44:32.254 very much constant experience in self right so there's this feeling undertone 00:44:32.254 --> 00:44:36.314 if you want of the conscious state but i don't really see this as being problematic 00:44:36.314 --> 00:44:39.154 i mean my i have structures in my 00:44:39.234 --> 00:44:43.454 brain that assess my interaction with the world, right? 00:44:45.214 --> 00:44:50.374 So, and this can be expressed in a different, in an emotional undertone, 00:44:50.374 --> 00:44:56.254 like I can feel relaxed, I can feel stressed now talking to you or aroused and so on. 00:44:56.394 --> 00:45:01.914 And this defines, if you want, an emotional foundation. 00:45:03.293 --> 00:45:07.253 Upon which other information channels are integrated in my inner conscious scene. 00:45:07.513 --> 00:45:11.513 But I don't see this as problematic, really. What would be problematic about that? 00:45:11.773 --> 00:45:14.973 Well, this is what people have talked about being the hard problem. 00:45:15.093 --> 00:45:18.053 What is it like to be Paul Vachon? 00:45:18.293 --> 00:45:22.833 It is a lot down to what is the specific set of feelings that you experience 00:45:22.833 --> 00:45:25.433 as you go through your life, when you're sailing on your boat, 00:45:25.533 --> 00:45:26.753 when you're talking to us. 00:45:27.213 --> 00:45:30.153 But I get the impression that you're wanting to 00:45:30.153 --> 00:45:33.293 orthogonalize maybe that aspect of consciousness 00:45:33.293 --> 00:45:36.373 and what you see as the functional functional architecture of 00:45:36.373 --> 00:45:39.313 consciousness well so for 00:45:39.313 --> 00:45:42.093 the heart problem the so-called heart problem which is indeed how 00:45:42.093 --> 00:45:46.213 do we give a third person description of a first person experience um 00:45:46.213 --> 00:45:48.833 i think it's a little bit of fake problem it's a 00:45:48.833 --> 00:45:51.813 little bit of a red herring right i mean if we study 00:45:51.813 --> 00:45:54.793 memory let's say and we say like what's really what's the 00:45:54.793 --> 00:45:58.373 engram of a certain association where is it located we 00:45:58.373 --> 00:46:02.333 don't really pose this question like what's it what's it really like to be that 00:46:02.333 --> 00:46:05.953 engram to really have that information right it doesn't seem to be a real issue 00:46:05.953 --> 00:46:11.093 or we don't challenge a physicist with explaining to us what it's really like 00:46:11.093 --> 00:46:16.393 to be a chair from from a quantum physical perspective. 00:46:17.133 --> 00:46:22.073 Um quantum mechanical perspective this is it seems a question that but suddenly 00:46:22.073 --> 00:46:26.213 with with consciousness we all get a little bit flippy about the whole thing 00:46:26.213 --> 00:46:29.053 and suddenly we have to to know what it's really, really like to be that one 00:46:29.053 --> 00:46:31.413 specific bat in the world. 00:46:31.893 --> 00:46:34.313 Well, maybe we could also, well, but that's not really our problem. 00:46:34.533 --> 00:46:36.793 This is not really what we need to explain. 00:46:36.893 --> 00:46:39.473 Look, we have to also be clear about the scientific theory is all about, 00:46:39.633 --> 00:46:41.453 right? We have to explain, predict, and control. 00:46:41.913 --> 00:46:47.473 Do we have to explain human experience at the level of millisecond to millisecond 00:46:47.473 --> 00:46:50.573 record and explanation of single individuals? 00:46:50.833 --> 00:46:56.113 And I don't think that's true because for many reasons, we don't commit ourselves 00:46:56.113 --> 00:46:58.993 to that level of explanation from any other phenomena, attention, 00:46:59.273 --> 00:47:01.253 memory, and so on. And I think... 00:47:01.997 --> 00:47:06.837 There's a way to deal with this problem. So I have to be, I must explain how 00:47:06.837 --> 00:47:11.417 a conscious being can experience just anything. 00:47:11.677 --> 00:47:17.197 I don't have to explain why it must experience hanging off the ceiling or something like this. 00:47:17.237 --> 00:47:23.777 So that means I have to explain the potentiality of experience and the mechanisms 00:47:23.777 --> 00:47:25.257 underlying this potentiality. 00:47:25.257 --> 00:47:28.237 It's not our our responsibility i 00:47:28.237 --> 00:47:31.997 think to really be able to to take a single subjective state 00:47:31.997 --> 00:47:36.977 and explain it but now the way we can make progress here i think is indeed by 00:47:36.977 --> 00:47:40.197 bringing in the robots i think this is this is important issue here because 00:47:40.197 --> 00:47:45.117 essentially the problem with with the third person perspective on subjective 00:47:45.117 --> 00:47:50.877 experience is that we cannot control time right if if you go back to indeed psychoanalysis, 00:47:51.057 --> 00:47:55.657 then there you would say, well, I have subconscious factors that sort of feed 00:47:55.657 --> 00:48:01.377 into my behavior and my experience, and I have to gain access into these. 00:48:01.517 --> 00:48:04.277 I have to sort of get to catharsis to improve myself. 00:48:04.697 --> 00:48:09.237 And for that, I have to delve into my memory in a very complex process to relive 00:48:09.237 --> 00:48:11.297 my whole life to find catharsis. 00:48:11.357 --> 00:48:14.917 So it illustrates, if we could just control time, if you would have a time machine, 00:48:15.037 --> 00:48:17.817 you You could go back in time and see, okay, did my mother really beat me so 00:48:17.817 --> 00:48:20.577 much when I was young, as an example. 00:48:20.757 --> 00:48:24.257 So with the robot, I have this potential. 00:48:24.377 --> 00:48:29.477 With the robot, I can control time because I can measure all the states of this 00:48:29.477 --> 00:48:31.237 machine as it evolves over time. 00:48:31.557 --> 00:48:37.237 So now if the robot at the age of 20 suddenly looks at the yellow microphone 00:48:37.237 --> 00:48:42.037 and thinks of the sunset, I can actually enter that system and parse. 00:48:42.117 --> 00:48:47.157 I can interpret its subjective state. and I can also explain where this content 00:48:47.157 --> 00:48:50.117 came from. And I think this is the best we can do. 00:48:52.284 --> 00:48:56.764 Well, I think we've had some strong predictions from Paul so far, 00:48:56.864 --> 00:49:03.184 and we've already tied him down to saying when we'll have met the goal of creating a conscious robot. 00:49:03.824 --> 00:49:08.564 I think as we do in all of these interviews, there are certain questions at 00:49:08.564 --> 00:49:11.404 the end, and Paul's had a long time to think about and prepare these, 00:49:11.584 --> 00:49:13.384 so we're expecting great answers. 00:49:13.384 --> 00:49:16.464 So the first question uh paul is 00:49:16.464 --> 00:49:19.104 uh a lot of what we do here in 00:49:19.104 --> 00:49:22.004 bcbt is about trying to inspire next generation 00:49:22.004 --> 00:49:25.164 of scientists and uh by 00:49:25.164 --> 00:49:30.344 polling uh experienced scientists about their experience about how how to progress 00:49:30.344 --> 00:49:36.764 the field so from your own uh history and experience what is your advice to 00:49:36.764 --> 00:49:41.464 more junior colleagues what is paul's law about how we're going to make progress 00:49:41.464 --> 00:49:43.144 in the science of the brain. 00:49:43.764 --> 00:49:47.004 Well Paul's law would be to commit yourself to the real world. 00:49:47.864 --> 00:49:54.444 So you know a lot of science we see is theoretical science like recreating nice 00:49:54.444 --> 00:49:58.464 pictures in some piece of software that look like a picture you found in a journal 00:49:58.464 --> 00:49:59.924 and say ah this is my model of the brain. 00:50:00.444 --> 00:50:04.584 It's not good enough. We have to. It's all about performing the experiment of 00:50:04.584 --> 00:50:08.284 submitting your ideas to reality and there are different ways to do that. 00:50:08.344 --> 00:50:11.864 We can do experiments, test our predictions there. We can build robots. 00:50:12.704 --> 00:50:17.504 The robot works or it doesn't. It's a very simple test of a theory to start with. 00:50:17.664 --> 00:50:23.504 But the third way to be real and test ideas is in the clinic. 00:50:23.644 --> 00:50:28.324 If we claim that we know how the brain works, you must be able to fix that brain as well. 00:50:28.864 --> 00:50:33.184 So I think these are the kinds of challenges we can face to benchmark our understanding 00:50:33.184 --> 00:50:37.964 and submit it to reality as opposed to submit it only to social factors of the 00:50:37.964 --> 00:50:40.044 appreciation of our colleagues and so on. 00:50:41.554 --> 00:50:46.574 Okay. And the second question, which we've also already tied you down to some 00:50:46.574 --> 00:50:51.934 predictions, but let's see if we can make something slightly shorter term and really concrete. 00:50:52.134 --> 00:50:56.354 So in five years time, we'll be here for BCBT again, funding allowed. 00:50:56.814 --> 00:51:01.214 So, and we will be able to come and see your iCub robot. 00:51:01.774 --> 00:51:07.594 What do you predict that it will be doing? And what will that tell us about consciousness? Okay. 00:51:07.714 --> 00:51:14.074 So I predict that I can engage in fairly complex dyadic, so one-on-one interactions 00:51:14.074 --> 00:51:16.154 with humans in unpredictable environments. 00:51:16.474 --> 00:51:19.274 But the most specific prediction is that in five years' time, 00:51:19.454 --> 00:51:23.814 we will be able to parse or to interpret the subjective states of this machine 00:51:23.814 --> 00:51:29.054 that are comparable to the subjective states we might find in other animals such as ourselves. 00:51:29.974 --> 00:51:33.614 We'll be able to ask iCub if it's conscious or not? Absolutely. 00:51:33.674 --> 00:51:36.774 You can ask it today already. And maybe it'll say no. Exactly. 00:51:38.794 --> 00:51:43.674 Exactly right. No. Well, you know how it is, right? People can say whatever 00:51:43.674 --> 00:51:45.734 they want, but why would you believe them? 00:51:45.914 --> 00:51:50.134 So, but the same with robots. So I think we will have better methods to do that. 00:51:50.834 --> 00:51:53.974 Okay. Thank you very much, Paul. You're welcome. Thanks. Thanks a lot. 00:51:53.680 --> 00:51:59.600 Music. 00:51:59.394 --> 00:52:05.294 The CSN podcast was produced by the Convergent Science Network of Biometrics 00:52:05.294 --> 00:52:11.694 and Biohybrid Systems, a project funded by the European 7th Research Framework Program. 00:52:13.234 --> 00:52:18.574 For more interviews, recorded lectures, or upcoming conferences in the field 00:52:18.574 --> 00:52:24.814 of biometrics and biohybrid systems, go to csnnetwork.eu. 00:52:25.040 --> 00:52:33.040 Music.