The Neuroscience of Consciousness

so good evening what a great audience so welcome to the final lecture in the Melbourne Neuroscience Institute public seminar series I would firstly like to acknowledge the traditional owners of the land in which this event is taking place the land of the word and Jerry and pay respect to their elders and families my name is Trevor Kilpatrick I'm director of the Melbourne Neuroscience Institute at the University of Melbourne the mobile Neuroscience Institute or MN is we like to call it is the principal body for the promotion of cross-disciplinary research in the neurosciences at the University of Melbourne the mni supports engages and facilitates high quality projects with an emphasis on value adding through coordination of effort and collaboration and aims to showcase the university's prowess in fundamental translational and clinical research in the neurosciences and related disciplines we are very pleased to be hosting Baroness Suzanne Greenfeld CBA here at that CBE here at the University of Melbourne Susan is a British neuroscientist writer broadcaster and a member of the House of Lords specializing in the physiology of the brain Susan researches the impact of 21st century technologies on the mind how the brain generates consciousness and interrogate Snowville approaches to neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease Susan Greenfield was an undergraduate at st. Hilda's College Oxford she took a DPhil at the University Department of Pharmacology at Oxford and subsequently held research fellowships in the department of physiology Oxford the collège de France Paris and NYU in 1985 he was appointed university lecturer in synaptic pharmacology and Fellow and tutoring medicine linkage College Oxford becoming a full professor in 1996 has since been awarded 30 honorary degrees in the British and fought from a number of British and foreign universities in 1998 she was appointed director of the Royal Institution of Great Britain and she's currently director of the Institute for the future of the mind at the James Martin twenty-first century school as well as a senior research fellow at Lincoln College and honorary fellow at st. Hilda's College all of the University Susan Greenfield holds a multidisciplinary research Held's heads a multidisciplinary research group exploring novel brain mechanisms linked to neuro degeneration she also studies the physical basis of the mind in 1995 she published her own theory of consciousness journey to the Centers of the mind which was further developed in the publication the private life of the brain in 2000 edition she was has developed an interest in the young mind and the impact of 21st century technologies on how young minds think and feel having said all this it is a great pleasure a pleasure to invite Baroness professor Greenfield to deliver her lecture the neuroscience of consciousness thank you well thank you very much Trevor a huge pleasure to be here and I'm told that you at the back can hear me is that true hands up if you can hear me oh it's audience participation straightaway it's wonderful to be here and I very honored to spend a very exciting day at this fabulous new building I'm really jealous I think all my colleagues and ox will be jealous at the facilities that you have here and just the way it seems to help you think you know sort of environments I imagine if I worked here would really aid and abet constructive creative thinking and conversations and so on so for all of you who had a part in that and I know Trevor has won many many congratulations I think it's a fantastic facility so one thing though that Trevor didn't mention which I'm really proud of was in 2006 among all these other Garland's and blue ribbons and so on I was awarded honoree Australian of the Year this doesn't help me through customs or these are but I do have the plaque like the t-shirt have the plaque on Australia for someone who shows Australian values I'm not sure what they are plus as your beauty but someone can enlighten me at some stage anyway I do feel that Australia really is my my second home especially in the summer months although I have to say this morning did remind me very much of all stones this morning anyway um you're not here to talk about the weather we're here to really talk about something I think is a fascinating question they're not just scientists not just neuroscientist or anyone surely surely must think about and I would argue one of the biggest questions any human being can ask which is what are you experiencing right now and however close you are to the person sitting next to you however articulate however musical however poetic no one can share what you're experiencing now firsthand it's this wonderful subjectivity that is absolutely unique to you that makes things so special makes life worth living if someone says you're never going to be conscious ever again wouldn't that be tantamount to dying effectively so this inner experience that no one else can share poses I think as the biggest issue facing us the biggest question the biggest fascination what is it how can we understand it how does it how does it come about well let me just say straight away I'm not going to be answering any of those questions what I am going to try and show you is how neuroscience can bring to the party I think a valid contribution it's not going to be the answers but I hope that along with the philosophers and all other of the great thinkers who for centuries have considered this issue that we do have a contribution that we can make which means that of course if we're talking about neuroscience if we're seeing this through the prism of the neuroscientist inevitably we start with this rather unpromising looking object on the screen now I love this picture because it does remind me a long time ago when I was a student in Oxford and we had to dissect a human brain professor finca was in that very department of human anatomy at Oxford where they wheel on these trolleys containing sort of Tupperware buckets with human brains inside them and for have people detected hands up whose dissected a brain oh god I'm talking to the convert everyone's daemon neuroscientist well prefers you didn't put your hand up please listen to the story and those of you who did bear with me because I think it is worth a thought that there you are with the brain in formalin fixative to enable you to dissect it so you're wearing surgical gloves and I remember perhaps those of you put your hands up had this this very same experience I sure lots for show of hands admit if you did you put your hand in this bucket and then you hold just like in the picture you hold a human brain in one hand and I remember thinking if I wasn't wearing surgical gloves and a bit for some reason dislodged under my fingernail would that be the bit that somebody loved with would it be a habit would it be a memory would it be a habit like let's say biting your fingernail can you have the habit of biting your fingernails underneath your fingernails okay hands up people with their hands up hands up who also I've had those thoughts you must have yeah oh yeah well done yeah so that this brings home to you the the fascination of neuroscience and how can almost drive you mad actually and perhaps someone would say that is a prerequisite for neuroscience that you have to be sorry about is that how can something that gets under your fingernail give you the experience you're having that I mean it it's such a sort of leap to make through something that's just really kind of mushy and boring to something that makes your whole life worthwhile so how do we get there what is it if we talk about the neuroscience what is it that translates into something that is you something that is so subjective and personal this isn't you this is George Bernard Shaw and the reason I like this picture is because you can just philosophy hate this I think just tell he's thinking and just tell you thinking yeah what what's going on behind those piercing eyes what's going on behind your piercing eyes even if they're not piercing what's going on that gives you this subjective take on the world this phenomenology that we call consciousness so that's what we're going to look at we're going to see how neuroscience can help us make some kind of progress and perhaps I should say from the outset what we are not going to be able to do is work out how the water is turned into wine how does the water of boring old brain cells and sludgy stuff translate into the wine of phenomenological subjective experience so let's start nonetheless with some assumptions the first might seem pretty obvious and that is sadly the consciousness can't be formally defined now this really does exercise many people and indeed for some they actually shrug and give up can you imagine we wouldn't have any more lecture if we gave up now because we can't formally define it I think the problem is that normally our strategies for defining things fall down here there's two broad strategies that normally would use to define something one is referral to a higher set for example I'd say our table is a piece of furniture love is an emotion consciousness is a is a while more is it there's no higher set of which consciousness is a subpart the other is operational definitions flight is when you defy gravity consciousness is when when you do what you're not doing anything apart from laughing at my rather poor jokes and yeah I hope you're still conscious at this early stage of the talk so so therefore our normal strategies either operational or referral hiset don't work and that's why I think we flounder in trying to define find what it means now if you're a neuroscientist if you're scientist happily these nuances don't worry us because what I'd like to suggest is a working definition of consciousness and I don't know if there's any philosophers in the audience they're off and on they never put their hands up FS any philosophers until the ADA is won until the end when they are some highly technical and erudite question and they've been sort of keeping themselves in disguise but I know that under white dress you as the token for loss of that but I'm sorry if it's offends you but I'll just give an informal definition that it's just what I described it's the first person's subjective world as it seems to you it's let's be even more crude it's what you're going to lose tonight in all probability and even worse we all know what conscious is is don't we so why don't we just press on and see what progress we can make so any of those levels I'm afraid aren't very academic but if we're to make any progress and that's we're all going to go and have the drink right now I'm afraid we have to live with this rather inadequate forms of definition this problem of the water into wine the translation of the squalor of everyday brain cells into the subjectivity of your wonderful experience has been called by someone called David Chalmers an Australian for heart problem pretty pretty straightforward and I'd like to suggest that this hard problem is very simply that what's the difference between sleeping and wake fullness now some people have other concepts of consciousness that I think can actually confuse us but I just like to clear the out the way right now some people talk about self-consciousness and I'd like to suggest you that that is an add on and add on luxury on normal consciousness it's something that after the age of one and a half two years of age human beings are capable of having but I don't think a rat ever looks itself in the mirror and says I'm a rat you know they're not myself gone but they could be conscious so is it so I wouldn't like to trouble us with this notion of what philosophers call meta representation that is to say this notion of self-consciousness the other issue is subconscious any devotees of Freud of course will be very familiar with that where you are conscious but you're not conscious of a particular thing even though it may inform that current state so I don't want to really focus we can in the QA on the subconscious or self-conscious I simply suggest the hard problem is going to be enough for anyone for an hour that is to say the difference between unconsciousness and common or garden raw consciousness I'd also like to assume it's generated by foreign of the brain because that's an area that I'm familiar with you might think this is pretty obvious but I just put it as an assumption because it is some people so-called pan psychics as far as I understand it posit that perhaps consciousness is an irreducible property of the universe it's there somehow out in the ether and your brain is like some kind of satellite dish let's or picks it up somehow now one can't prove or disprove that and therefore it's not very useful if we're trying to make a journey now if we're trying to make some progress especially in relation to the brain so I would like to pay my respects to that theory and place it to one side as something that's not going to be in our sights in our crosshairs this evening and finally any scientific explanation must include this quintessential feature of subjectivity now why have I put scientific in inverted commas like that it's because it's a word that's often used and it's because in science you are ruthlessly objective as I'm sure given the number of hands that went up there's many scientists in the room we all know the whole essence of science is Jek tivity it's impartiality you are an observer and you observe what someone else observed and it's reported even in the passive so you would never say I made up a solution because that sounds fishy you'll say rather torturously a solution was made up oh yeah because just absolutely preserves the fact that your solution is the same as someone else's solution the agent is trivial relative to the action however where does that land us if we're thinking about consciousness given it screams essentially subjective and this is why I think so many scientists are very leery of studying consciousness why you can't apply for grants to study consciousness you have to disguise it as schizophrenia or anaesthesia or something like this and some workers actually said that any scientists trying to embark on the neuroscience of consciousness is a CLM I bet you can't guess what a CLM is it's a career limiting move okay so these are the assumptions that I place before you and so long as you buy into this along with my promise that I won't be able to turn the water into wine stick with me because now we can go on our journey and this is where we start so there's where do we start so there you are you are going to adopt a neuroscience approach we've defined something as quintessentially subjective that's I'm going to be related to the brain and here is a brain in City let me just look at it again occupies the same universe as tooth enamel or earwax or nasal hair and yet it does so much more how does it do that how does it do those things it's pretty banal looking at it like that so the perhaps and again those of you who aren't neuroscientist perhaps you're also familiar with the very obvious feature that the brain is characterized by these anatomically macroscale brain regions like this cauliflower looking thing on the back where is it okay icon is it where's the pointer I'm frightened I'll get other so yeah where we are so this thing on the back and outer layer and the spinal cord and so on so that begs the question and many people when confronted with the brain and asked to study consciousness will immediately say well is there a center for consciousness is there a brain area that generates conscious very straightforward idea so let's try and look at that one first could one of these areas be the Center for consciousness so that's what I think there's no such thing as a Center for consciousness why do I say that for two reasons first it actually doesn't make much logical sense just think of a brain within a brain being a sent way as a center anyway just out of interest what happens inside a center doesn't really doesn't really help us saying something's a center for something and anyone I don't know if there's any people who lived in England in the 50s and 60s when I was young and read a comic called the Beezer and they featured these characters called the numbskulls and the numbskulls lived inside this little man's head and got him up to no end of mischief and it's a she was my first lesson in determinism mentioning anyway and you have the crisper eating Department and then you had the eye Department the nose cleaning Department notice the doors are rigidly shut the compartments are solid top left is the consciousness center clearly the chief numbskull in his room so I with all humility suggest this might be a metaphor for people that say their sentence for this and that right now if that was the case we ask ourselves as I say what goes on inside the center so what goes on inside the numbskulls brain are their mini numbskulls and inside the mini numbskulls are their micro Nam skulls and then are their Nino numbskulls and pico numbskulls there so you end up miniaturizing the issue but has that actually really explained anything it's what Ramachandran calls an anesthetic explanation that's to say some of the sounds good but actually when you think about it doesn't really doesn't really help you so if we're looking at a Center for consciousness I'd like to suggest you that actually doesn't really make sense in any way we know the brain doesn't work like that the neuroscientist will know there's for vision for example at least 30 different brain areas related to vision that div is up the job into coliform emotion and we know that any one brain area will participate in many functions and I say any one functions dip it up so it's not as if you have a one on one of brain function and brain area tying up together and moreover we can look at empirical evidence also suggesting that there is no such Bing as a single Center for consciousness in this experiment what they did was to administer anesthesia thereby abolishing consciousness and you would think if there was a single Center for that facility as the anaesthesia was given one area on one error alone would suddenly shut down and I hope you can see here that that's not the case so this is with beaver cane and anesthetic and with MRI scanning I'm sure people especially here are very familiar with this and if you're not all you have to focus on are the bright bits the yellow red bits and as you can appreciate everything uniformly shuts down as the anaesthetic base is increased so looking for a Center for consciousness isn't a very helpful start I would suggest for a neuroscience explanation because there's no I would suggest there's no such thing second what are we going to do you see I think we need to work out what the problems are first and drop a shopping list and only then go to the brain so what we going to do about this next problem of non-human versus human consciousness this is something that people do think about a lot and it strikes me if you look at the anatomy of a range of species in the animal kingdom I would defy anyone to draw a clear Rubicon a clear anatomical line where one load of species are disenfranchised as being unconscious and kind of robots and the other group are highly we're not highly sentient but have some kind of inner in a state I would be confident as you can see here although the brains vary hugely the theme is the same the theme is always the same it's just variations on a theme that are characterizing the species so I don't think that we can with confidence point to an area to study and moreover and I owe this to a marine biologist who gave up marine biology to take up neuroscience he worked in my lab for a while he pointed out this with the octopus now the octopus has a very different type of brain from us but nonetheless the octopus vulgaris is sufficiently worthy as to get home office in UK at least home office legislation that's means to say you cannot just cut up an octopus vulgaris if you want to for an experiment and actually they have featured a lot in experiments the old days was amazingly with memory memory discrimination tests but more recently this type of octopus showed great prescient sin the World Cup I don't remember Paul Graham burp all the octopus who obviously was conscious because he predicted the victory of the various teams sadly it died so clearly a conscious October's and yet and yet the L had NC Xhosa apparently are very similar species you could cut up so this shows the arbitrary nature of trying to draw a distinction between if an animal is conscious or not conscious where do you draw then if you can't draw the line you shouldn't draw a line and therefore we do have a bit of a riddle going on that actually can relate even more controversially to another scenario so where's the difference you say this Atlanta mall this dog is doing something outside of the canine repertoire normally should bite the lady or run away but the very fact that the dog is doing something humanoid and we know that dogs aren't humans the reason I find this rather enchanting little picture is it does suggest the dog has some kind of inner state and yet somehow it's different from ours and it doesn't correspond to the behavioral state so I think the animal consciousness as I say leads to a way more controversial issue of fetal consciousness is a fetus conscious try asking is a dog conscious or as a rat conscious fetus conscious now let's assume as many have for many years the null hypothesis that's to say we assume the negative let's assume it's not conscious so if that's the case if the fetus is not conscious when does it become conscious is it as it squeegees down the birth canal will that be tough if you're born by cesarean section it means you're never being conscious or is it exactly a full-term so that raises the rather strange scenario of parents who have a premature baby they're sitting at hamster our baby's conscious today when we might as well going to hospital and see it wasn't conscious yesterday does that seem likely no doesn't so as far as the brain is concerned the oxygen whether it comes through its own nose or through mum is not going to be the deciding factor so when would a fetus become conscious when it's born when it's a month old two months old I'm sure many of you have babies so I know one person this has a you baby and you don't suddenly say well so the babies become conscious all of a sudden so if you reject the null hypothesis that it's not the manner or timing of birth that is a deciding factor then surely we have to reject the null hypothesis and entertain the possibility of the fetus is conscious now I don't want to get into the ethical issues here we can if you like but I'm not here as an ethicist it's more the issue of this being a very similar question to whether animals are conscious the same rhythm is it winter the lights go on when do they go on when do they go off how can we get round that because we need to get round that before we even start looking at the brain if we are trying to understand what we're studying well so the problems there are more problems now Center for consciousness non human fetal consciousness how can we explain this well perhaps a clue comes if we look at the actions of anesthesia in removing consciousness I don't know how many of the clinicians who are familiar with bismallah Turing I gather an ox of the anesthetist don't like it very much suffice it to say it's a system by means of monitoring the brainwaves from your skull that gives a number as on the left showing the depth or allegedly showing the depth of anesthesia this was developed to prevent unnecessary death during anesthesia and also the rather harrowing experience of being conscious during surgery so the whole idea is that you can put a number on a level of consciousness now if you can do that surely that means that it's not all on and we've known for a long time everyone at Medical School have learnt the levels of anesthesia and it did the depths of sleep and I was reflecting on this when I was on holiday at one stage and I thought well if you can have graded anesthesia graded sleep continuously variable unconsciousness why can't be the same for consciousness now if that was the case that would get us out of a great fix first of all it would explain the riddle a fetus could be conscious but not as conscious as a child and the child could be conscious but not as conscious as an adult and a rat could be conscious but not at work octopus conscious but as not as conscious as a rat and rap conscious but not as conscious as a cat cat conscious not as conscious as a pro so you have wonderfully now been able to accommodate that Riddle and it also introduces a rather interesting idea that you as an adult human being will be more conscious at some times than at other times and if you think about our kind of folklore way of talking about consciousness we talk about raising our consciousness or deepening our consciousness don't we doesn't matter which way you go whether it's up or down doesn't matter but we're now doing something that scientists love we're quantifying something whatever is we're now introducing something that potentially we can measure so I'd like to suggest you that consciousness is not the lights on all the lights off but more it's like a dimmer switch and that consciousness could grow as brains grow and then you as an adult human being will have different levels and that only we could find a correlation for that process then indeed neuroscience might be doing something useful so what we are doing now we're in search of a process where consciousness is continuously variable something like a dimmer switch now what could there be in the brain well let's look at the candidates ok here you have neuroscience presented in one slide representing the top-down and bottom-up approaches here on the left is the so called bottom-up approach where forgiveme neuroscientists but because a lot of people here are general they may not have been familiar with these terms the bottom-up approach which you can do traditionally with electrodes looking at the changes in voltage generated across the cell membrane as seen here that's great because it has a high time resolution in it but you only look at one cell and you can see those spiky things there the signals the electrical blips that a cell will generate now you could do that but then we really want something that is going to vary in degree don't we and so therefore looking at a single cell which anyway might die so it wouldn't be very good have a cell as the Center for consciousness I don't think that's a very good candidate similarly looking at scanning which I know is brilliantly done here this is magnetic resonance imaging and you can see these kind of pictures I'm sure you're very familiar with them they tell you about the activity of whole brain regions but the spatial resolution is quite coarse and the I am resolution the time resolution is several seconds whereas on the Left those little blips are a thousandth of a second so really we want something that can vary in degree in again brain regions for one second or subsequent to the next won't vary in degree so what we want is something that thinks these two and this has been the Holy Grail in any event for Neuroscience for a long time reconciling the top down on the bottom up approaches with some kind of mezzo scale mid-level process and if that mid variable process was something that was analog wasn't all or none then I would suggest that would be a very fruitful place to start prospecting so there is such AI would have set that up if there wasn't such a thing and I'd like to introduce you to what we call in my lab the names vary so bear with us but in my lab we call these this middle level thing that I'm going to explain we call them neuronal assemblers neurons or brain cells and assemblies are we're talking as variable transient large-scale groups of neurons that are not defined by anatomical systems so they these ideally this system we're looking for these assemblies occur in less than a second and at the same time they incorporate they will recruit large-scale not just a single cell up to 10 million or 100 million brain cells so this is what we're looking for and what we can do in order to explore this is to use something called voltage-sensitive dye imaging if you want pack each of those it's not that complicated it's simply you give a dye it embeds itself in the membrane of the cell and then it would change its wavelength it will 4s as the voltage across the membrane changes this was pioneered by people like Ameren Grunwald at the vitamin Institute in Israel in the 1990s in this technique that we've now adopted in my lab now the downside of is you can't use it in humans because you don't want to give a potentially toxic dye onto human brain tissue but you can use it in animal models and that's what I'll be showing you so here we are this is from my own lab and I hope you can see ok so this is the edge of the brain need this okay so this is the edge of the brain and as you might imagine after a very short electrical stimulation of about a microsecond you can see these are thousandth of a second milliseconds can you see that very quickly a pattern emerges with a very strong epicenter and then a decaying amount of activity and all this happens in about 18 milliseconds 18,000 serve a second you would not see that with conventional imaging now it strikes me that this season your own assemblers and as they can look at how nice they are that this could be something that could be a potential correlate for understanding variable degrees of consciousness as you see it varies in size and as you can see it has an epicenter that then decays a bit like there like a stone in a puddle and that's the image for those who are not scientists try and think of that I'm going to try and sell to you as a theory is that consciousness is correlated with the brain equivalent of a stone being thrown in a puddle the stone is very local it's very small and it's quasi permanent and yet it would generate much broader highly evanescent ripples that vastly the excursion rivers vast exceeds the stone but they're gone in a second and we feel very we can vary the extent of the ripples either with the size of the stone the force it's thrown the competition from other stones but nonetheless that excursion whatever it may be from one moment to the next will be different that could be correlated with degree of consciousness that's what I'm going to try and suggest you so here is another film okay what you're looking at here before I start the film this is a mouse brain and this is the plane up section and then this is what we see in our bath this is an area of the brain you don't have to worry about it where we put our stimulating electrode but it projects to this outer layer of the brain and what you're going to see here in this little film is when we stimulate here the activity in this remoter part of the brain that's been conducted via this connection and you can follow its trajectory along here you can see if there's something going on here and you might like to look at the time scale here okay so let's let's look at that so can you see the activity shown by the present blobs and as we're getting to about 200 milliseconds in this case there's peak activity that then is gone and by the time we're still way less than a second half a second is completely gone pretty much after that stimulation so that's what we work on that's a neuronal assembly in a dish and we can therefore study its properties so if you agree that such things exist and that such things might potentially be called candidates for reconciling top-down and bottom-up now now we can go to the brain and ask it to deliver some things on our shopping list the first following the analogy of the stone in the puddle the first thing we want to know is what is the stone now for neuroscience that's quite easy actually this is an easy one what could be the stone well very simply it could be some strong sensory experience and on defy anyone who says they have a good correlate of consciousness or a theory of consciousness to answer the simple question undeniable that an alarm clock wakes you up why should an alarm clock wake you up it will wake up a baby it will wake up anyone irrespective of their culture their language unless you are of course totally totally disowned death songs your ears are working an alarm clock will wake you up why this theory would be that this is the equivalent of throwing the stone very forcefully a very strong throne will generate enough reports for consciousness so a sensory experience could be the stone in the puddle very noisy or bright light will wake you up anything is very strong will wake you up but we don't go through life do we just you know being woken up by alarm clocks and bright lights there's another aspect especially to humans so I think we need to consider and I'd like to suggest we're now looking not just at the force with which a stone is thrown but the size that the stone would be what could determine how big the stone is because the nice thing about this idea she says modestly is that there's different factors that we can vary like for stone is thrown now the size of the stone will in the human brain we know there's a lot of potential for so-called hard wired connections that's a phrase I don't personally like because it does suggest too much analogy with computers and we can argue the toss over that if you wish later but I'll use that word anyway to distinguish it from the evanescent assemblers so if we're talking about something that's quasi permanent connections that are quite permanent as you can see what characterizes the human brain superlatively more than any other species other species great realistic sense will have this facility we have it superlatively which is as you can see the growth of the connections between brain cells and it's the growth of connections that characterizes the growth postnatally of the human brain so that even if incidentally you're a clone an identical twin you will have a unique configuration of brain cell connections why because these will be crafted and formed and updated and strengthened and so on by your individual experience as you go through life so you're born in the words of the great William James into a booming buzzing confusion and you'll evaluate the world what else can you do how sweet how FAR's how cold how bright but gradually as the week's turned to months turn to years as the connections form an erstwhile abstract visual display will now be a pattern it'll be your mother's face and if mum and let's hope she does features again and again again and I have more connections will form that face will mean something to you that it does not mean to other people and then we make the transition from what we call sensory to cognitive after the Latin cogito I think so I'm going to suggest you that as well as the stone being important in terms of the four so that it's thrown its size it's size is important that in turn will reflect your cognitive status say you are living your life downtown Oxford people think it's like this where everyone everyone is doing their own thing and everything you do has its place in space and time it can't be undone I'm sure everyone in this room has passed an exam but you can't unpassed it and it might be that you've failed other exams you didn't make the most of that exam maybe that was the start of your career it doesn't matter that's an event in space and time that happened to you that's part of your identity that may be responsible for many other things that have subsequently occurred and this sequence of events this unique life story this narrative that enables you to see the world in a way that no one else does to evaluate it in terms of what you've experienced gets more and more rich and diverse as you go through your life so you go from this one-way street how sweet how fast are cold how bright to a two-way street where everything that happens to you evaluate in terms of your previous connections and at the same time the ongoing experience will update and upgrade those connections and this wonderful sequence of events that makes you the person you are this identity is leaving its mark literally on your brain so incidentally that's what I would call the mind it's not quite the same as consciousness it is the personalization of your brain through the unique configuration of brain cell connections that are quasi permanent but they are not enough to generate consciousness they're too local they're too long-lasting to be they're too slow to form these so connections to be responsible for the kind of sub-second events that we need to account for okay so I'd like to suggest you that as well as the force we have the cognitive experience which is the degree of neuronal connectivity these are some of my colleagues in Occident if professor Fink may or may not recognize them but for me this is a very special photo it was one of those rare occasions which signed a contract with University for money and never that's why everyone's looking vaguely nervous and smiling at the same time now for you looking at this you didn't know that you'll just see this is generic middle-aged men in suits and ties say there were typical scientists property and that's about as far as you go whereas me I know the names all these people I know a lot of their dreams and hopes and problems and worries and this Bay in particular was a very special day it's triggering in my brain even as I look at it now many meet one person this has died many many thoughts and feelings that you won't have you'll just see this is rather boring picture that of all middle-aged people just standing in a row whereas for me it's very special it means something so this cognitive experience is due to the connectivity of my brain so we've got then the stone we've worked out how it can be thrown and that being a variable we've worked out what could be the size of the stone now we get back to the nitty-gritty how does the assembly actually form how do those ripples get generated when you throw the stone why should an activated hub of cells let's say - an alarm clock let's say - your mother's face why should that then generate and recruit a large-scale coalition of brain cells well we need to know something else about the brain again I'm aware I'm talking to a split audience of highly specialists and perhaps people who are less familiar but all you need to notice about this are these kind of chemical fountains in the brain don't worry about the names you may recognize serotonin as one of the agents that's a target for prozac for depression antidepressant drugs so these chemical fountains these a means in the brain are actually very diffuse as you can see they go everywhere and they are related to sleep wake cycles to arousal levels and this has been known for quite a long time this well known is the way they work the way they work is not so much as one on one chemical messengers they're not really equipped if you look at the distribution to do that so easily but now in neuroscience we've spoken the last decade or two about modulators and a modulator is a chemical it can be a transmitter as well but a modulator is a chemical that predisposes a cell usually makes it more sensitive to a response but you then need the response this is the one technical picture I'm going to show you of one of those agents a sitar choline acting as a modulator and bear with me if you're not a neuroscientist all you need notice is that when acetylcholine is present in the two lines in the center there's more action potentials there's more blips that's what modulation is even though the stimulus in each case that's to say this kind of rectangular box at the bottom of a blob on the top one that's the same I hope you'll appreciate that acetylcholine in itself not doing anything has made it easier for the cell to generate blips we can go into the into the biophysics there if you wish in the in the Q&A but I don't think it's necessary all you need to know is that these agents that are responsible for arousal and wakefulness complete dispose cells to respond in a different way they will give you a variant response to an invariant input and that's how I personally would define modulation so let's put that to work hey Marcin your mum and that's what we could call an epicenter Isham with E the the square shows a hub of cells that are hardwired as I said because of your exposure and interaction with mum you see her so we've got now the stone being thrown in the puddle in this case would be highly cognitive it would be a big stone if your mum is shouting at you or if she's wearing kind of gold alarm a dress on she's holding alarm clocks or something like this then that will also add to the sensory component but it will be a payoff between sensory and cognitive the two together now what happens is those hub brain cells that we saw those fountains will be releasing chemicals in a very diffuse way as we saw and according to your state of arousal then that will determine how efficient they are in stimulating now or enabling the stimulation of the epicenter to recruit the assembly around them so we can see there's three factors there's the size of the stone there's the fourth of which it's thrown and there's now the modulators that will enable enable the recruitment of further cells even after the hardwired cells have been activated so that is how an assembly could be generated so let's just very briefly look at the empirical characterizations Amy sorry this is the only time I'll need you okay you just do the thing again sorry I'm signal so here what you see okay is here these are the brain sizes again TTX is an agent the blocks those electrical blips so in theory it should block out assembly and it does and then these other things here are the sort of things people like doing in pharmacology departments which is trying to show a specificity according to certain chemical messages and their molecular targets so again we don't have to worry but all you need to appreciate is that the one on the right is less than the ones on the left and the one on the top hasn't shown any activity at all for those of you who like this kind of thing that shows that it is physiological rather than just some kind of passive current spread okay so that's the kind of characterization we do in my lab and the sort of things we can understand about the nuts and bolts of those assemblies what about the explanations of this now let's go back to our problems so we still got problems so far we've got round the issue of not having a Center for consciousness we've got round the issue of non-human and fetal consciousness and we've talked about the action of anesthesia in terms of a reduction in assembly size or depth of consciousness now and I know there's lots of people here working on the modalities we have a very interesting interesting session earlier this afternoon I'd like to suggest you one of the big problems as well is the qualitative difference between hearing and vision now there are some people who've muddled up the two but most people know very clearly when they're seeing something as puts when they're hearing something there are two very different subjective experiences and yet in brain terms once you go past the cochlear or the retina the language of the brain is the same in both cases after the light is activated the retina or sound waves or cochlea they are transducer translated into those electrical blips again the same language and they're treated in the same way more or less so if they are processed in the same way in the same kind of code or language when and how does the qualitative difference when how does that subjective difference between hearing a vision come about how come you here and see very differently and yet and yet the brain is treating it the same way and if we knew that if we knew how to account for that subjective discrepancy then surely that would help us understand again the question the problem that we've posed ourselves so this is hearing a vision just in case you know it was so what we did in the lab was to see because with conventional neuroscience although the brain regions are slightly different to the best of my knowledge that haven't been very clear differences that one can really start to build a theory on so we looked at the difference between the visual part of the brain and the hearing part of the brain to see if the cymbal is there might be any different we found something quite interesting first of all these are 11 experiments using the visual system and I think now you're getting quite used to assemblers now privately so this is the edge of the brain this is the stimulating electrode directly applied this is the visual area shown here and you can see that there is a pattern whereby the epicenter the the most active area is as it happens down here this means it's in the deeper layer of the brain like that now this difference was only a parent or this cat was only a parent after about 300 milliseconds contrast it with the auditory system where having started out the same at 300 milliseconds we now see a polar opposite if at the edge here now that might be a start and it might be interesting then we have a real problem what's the problem it's not to do with the physiology not to do with comparing the visual and auditory cortices no that's not the problem the problem is how do we translate it to the phenomenology how if we've got the same yardstick for hearing and vision in neuroscience terms where we can see differences what's the yardstick that we can use phenomenologically for hearing versus vision and i mean if you so if you spent 4 Martian how would you describe how would you distinguish a hearing experience from a visual experience to them I wonder without being taught ologists and us agonizing about this and then one day it struck me but perhaps just perhaps when you hear something it's primarily but I stress not exclusively it's primarily a discrepancy in time detection of discrepancies in time where's vision is primarily but not exclusively primarily a discrepancy in space now if that was the case if we're after the same yardstick could we not put the two together and talk about a space-time manifold which physicists like to do that's to say where space and time are on a continuum where you can talk about them in the same breath as it were and if that was the case could we use space-time as a way for matching up the discrepancies we've seen here to try and understand it now this involves relativity theory about which I know nothing and I'm therefore in search of a physicist or anyone who can model these kinds of things who knows about relativity theory because one has ones over him it's a neuroscience I just can't do this and I would love to try and understand how these these logical differences which were observing might relate to space-time as a manifold okay so again back to more of a neuroscience approach you might say let's find all this kind of dancing around in brain slices or very pretty it's nice pharmacology and so on but surely we're interested in function and indeed we are what we want to do is extrapolate we want to extrapolate from a brain slice which we can manipulate very easily with a very high time resolution we want to extrapolate up here but here there's a very slow time resolution we've seen so we have to go on a rather secure to through ideally not we've done this yet what we need to do is to in a whole animal be able to apply our in vivo imaging which we can do because we can look at rat brains and at the same time a horror mole rat could be used for fMRI so we might want to start to extrapolate when we see one kind of thing what it might mean elsewhere and that's my long-term hope but in the short term we've got as far as doing it so good in vivo that's to say in an anesthetized animal and you can see very happily just what one would have predicted that with deep anesthesia here's the assembly sorry we'll stop with the light the animal has to be anesthetized obviously because it's an invasive procedure but as we did from the anesthesia you can see the assembly is reducing an amplitude or latency and in size here and you can see it here which is what you would predict if assemblies if anaesthesia work by reducing the size of the assemblies that's what you would indeed predict but you say what can these actually be linked to consciousness can assembly access all very well this neuroscience and until recently all I could do was suggest that this could be a candidate correlation until in the summer of last year I was delighted to get contacted by the press in relation to someone called Brandt Pollard's work I don't know if anyone's familiar with this and this was from his work last year there's the reference where he's introduced a new type of imaging that is not invasive it can be used in humans and yet it has a very fast time resolution I will begin to understand the technicalities I would suggest because I'm not professor pardon he's not here you could look up the actual mechanics of what he's doing but that's his colleague who looks a bit miserable they're actually events as humor can it's a bit sad but what was very nice and quite not always the case in science was he actually acknowledge me and this is from a quote from the Daily Mail not spent like your daily telegraph the Daily Mail so if you've made it in there you know you'd come quite well so lead researcher Brian Pollard University Manchester said the finds appear to support hypotheses but for bimah Oxford about the nature of conscious itself and that for me was a very greatest thing for him to do he didn't have to acknowledge me as we all know with the backstabbing that we call science politics you know Kissinger said why University politics is so spiteful because the stakes are so low remember that Curtin Kissinger and we all we've all been victims of that but nonetheless they wanted to and thank him very much for but nonetheless it shows that this idea which is still very much in its infancy might have some traction and might have some clear relation to consciousness so I'd like to end by now applying it if this stone in the puddle model these assemblies it can indeed serve as a correct not watering to wine it's not causally linked but if it's a corrected book correct we should be able to go from physiology to phenomenology and we should be able to go from phenomenology to physiology so let's see if we can do that let's go first with the physiology and as always in science what you want to do is to think of caricature scenarios because we always work with an exaggerated situation so let's imagine for some reason you had an abnormally small assembly what can we predict the kind of consciousness you would have now fortunately there's many ways in which you could have a small assembly one might be childhood which we saw has very modest connectivity another might be dreaming where whilst an alarm clock wake you up you won't be woken up with a dream because the sensory stimulation is so weak is just dependent on the intrinsic activity of the brain rather than being externally driven another might be schizophrenia where there is an abnormal modulation particularly of dopamine those chemical fountains another might be fast paced sports where you have competing assemblies so now the assemblers can't form because they're displaced by another and finally I don't know if you call them I don't know if the young people in the audience winced at me calling them raves and my dear we called them raves these are events where you go into a world stripped of all cognitive content yeah and just go Roseau techno techno techno techno damn and yes well okay so they're still called raids good there's no concrete content you're putting a premium on the senses and some people misguided Lee of course will be taking agents that interfere with the chemical messages with the connections so the assembly can't form as well nor is there any cognitive content so you have that small assembly now do what kind of consciousness with all these things have in common I'm not saying that children are schizophrenic although although there are there are there are similarities with children's gets a feel they can't interpret problems they have a short attention span there is a distractive and they have an under functioning frontal part of the brain called the prefrontal cortex which only comes on stream in late teenage years so can we think of the type we try describe it what it might be well clearly it would be something I would suggest that characterized by emotional content not cognitive something that is very dependent on reactivity to the outside world and for these different reasons you would end up with a small assembly that would be the net effect but you can see the reasons would be different but again why I like my own theory of course but it's my own theory is because you can vary the factors or the variables to have the same effect and that means you can we'll come onto this differentially manipulate them so if we're thinking about that think about being very excited because we saw it as a rater to arousal addiction I'm afraid if we're talking about drugs and reward this is a reward in case you don't know it wasn't like in all cases the chemical that features to help bring about these global brain states is the chemical dopamine and open when we know and this is a game from my own lab inhibits activity in the prefrontal cortex and you can see here the assembly apomorphine for the non aficionados is an agent that stimulates the targets that for molecular targets would open and you can see its diminish the size so we know inhibits and this has been done in many other ways houses with assemblies showing that so if that's the case could we imagine a cenar where you have a shutdown prefrontal cortex lots of dopamine and you're in a world you're in a world of yeah come one speeding and partying and wine women and song and drugs and sex and rock and roll where you've aggregated your sense of self you've let yourself go you've blown your mind you're out of your mind the very word ecstasy in Greek is to stand outside of yourself you no longer have that identity that carefully crafted identity for this moment you are the recipient of your senses like a small child so could it be here we are this is a rave this could be a hyperactive and and wretched prefrontal cortex might be a factor in the small assembly mode along with the document could we go the other way then if we characterize a larger small assembly as being highly emotional interdependent with the outside world can you imagine something where there's a flattening of effect a numbing of emotion the outside world seems gray and remote and I'm sure people who are in the business will recognize this immediately as clinical depression again an aberration in those modulating fountains so if that's the case one could say an imbalance of the chemical fountains and leads to a lack of pleasure the collisions here will notice a conscious or know that depression is associated with so-called anhedonia that literally means a lack of pleasure whilst the wine women and song scenario presumably is pleasure anhedonia is a lack of emotion person feels numb they're just so emotionally numb the world is grown remote the large assembly that in turn generates two hypotheses this is Fragonard swing this is someone we talk about being abandoned this is someone in small assembly mode Fragonard swinging I'd say that generate so therefore the greater neuronal assembly the less emotion and the corollary of that is that emotions the most basic form of consciousness now that's hardly surprising you only have to look at the tail wagging dog or the purring cat or the gurgling baby who don't have high cognitive content but clearly clearly are experiencing something or feeling something can we go the other way now from phenomenology to physiology well sadly what we've all experienced is pain and I want to suggest you the degree of pain you subjectively feel is related to the size of assembly here's suggestions why pain is largely expresses other associations pricking stabbing burning we see it in terms of other things there's a diurnal threshold to pain there's this terrible experiment for other sad must have been on bankrupt medical students where you put electric shocks through their teeth at different times of the day and they have to report when they feel the pain and in case you're interested it's easiest in the middle of the day that's when your pain threshold is highest now that's not because the conduction velocity of the pain fibers is changing it's because again I would suggest those modulators are fluctuating on a diurnal basis if you anticipate pain it feels greater phantom limb pain amounts like on wall you'll be familiar with I would call what they called a neuronal matrix and assembly where signals coming in signaling that the feedback from your limb the so called proprioceptive feedback that a limb should be there is absent phantom limb causing phantom limb pain pain is largely absent in dreams which i've suggested a small assembly stage and morphine the very well-known analgesic allegedly gives you a dreamlike euphoria and what's very interesting is apparently people on morphine say they feel the pain but it no longer matters no longer is significant in terms of other things and we know that morphine works via naturally occurring chemical targets where acts as an imposter to other chemical messengers and will reduce the size of the assembly schizophrenia I don't know who would do these experiments but they had been done schizophrenic people where I've suggested there's a small assembly stage they have a very high threshold to pain why you'd want to give pain to people who has schizophrenia how don't know similarly it's well known in depression and this has actually been done formally as well to press people have a very low threshold for pain which I'm suggesting is a large assembly site so that sort of fits and finally as we've seen anesthetic actions which prove no-one's really explained how they can deprive you of consciousness because they vary hugely in their structure and their actual mechanism of work if we go to the meso scale and posit that it's because they reduce the sizes we've seen that would also fit it would also give rise to the rather odd idea that if the anesthetic as it was worrying on wasn't bred hisham was doing this slowly the during anesthesia you should go through a small assembly mode so is it not a crazy idea that as you're being anesthetized you become perhaps aroused slightly mad and that's in fact what you do do the classic stages of anesthesia are hyperexcitability and mania would it be pleasurable well in the old days people took low doses of anesthesia as ether frolics or you take nitrous oxide at fairs and even now ketamine a drug of abuse is an anesthetic so there is this counterintuitive idea that I think is valid nonetheless that low-dose anesthesia or slow-acting anesthesia might take you through the small assembly mode so what does the future hold well I think that by using optical imaging we could reveal factors or the sort of imaging that Professor Pollard showed that govern the formation of these highly transient and therefore quality service samplers and this model could be linked to link the phenomenology of the physiology to be a correlation as I promised so degree of neuronal activities the physiology we call that intensity of the senses phenomenologically extender processing associations the physiology significance what your mum means to phenomenologically availability of modulators arousal availability of our predisposition or mood like hormones formation of competing assemblies distractions such as we might get in sports input from the prefrontal cortex what we will call narrative or your life story that is then abolished with your identity and then you could do this kind of thing which obviously I'm not going to go through but just on the top I hope you can see that this is the physiology and here is the phenomenology and you can make predictions by playing around with whether they're high or low predicting the Assembly size now and then correlating with the condition now I do not care as this is right or wrong but I do care passionately that it's for survival that it's testable and that's when you're a science can come in it can actually generate a full safar ball hypothesis which is really all that you ask of science you know you don't have to be right or wrong but you do have to be able to empirically test something and whilst we're not quite there yet this is the kind of thing I suggest neuroscience can do for the study of correlations of consciousness but we mustn't forget that a brain is not in a vat it's actually in a body and therefore it has to work with the immune system and the endocrine system in the autonomic nervous system otherwise you'll have biological anarchy wouldn't you so they must all work together and this some of you may be familiar with the work by Antonio Damasio has done a lot of work on so-called body markers somatic markers trying to posit a cohesion between the great control systems of the body and indeed the peripheral how it works and are going to suggest that really an assembly is not consciousness it's not in a dish it's not going to generate consciousness it's an index of consciousness so what could happen is you have your hub of brain cells the stone is thrown either by sensory stimulation or by the extent of associations that's to say the cognitive content and the sensory content other modulators will be available according to arousal levels or time of day hormones which we haven't gone into but all these agents will aid in a bit the facility of this hard wired hub of cells to recruit an assembly and again another factor will be the formation of competing assemblers but that is unconsciousness that's an index of consciousness what I then suggest happens is that signature that unique signature is read out to the rest of the body through chemicals called peptides which are Co localized with conventional chemical messengers that can be trilingual in terms of these other control systems of the body and these circulate round and indeed from the rest of the body they feed back so one has this iteration of these very multilingual chemicals they iterate round and eventually moment-to-moment subsequent sub-second accord all these different things going on your assembly size will be shrinking or expanding and that is the determining your degree of consciousness this is described in a far less garbled way it's a shameless plug for my book private life of the brain which was out a while ago but it's still going strong on Amazon I'm delighted to see although I'm writing a new one this year but if you want more details it's in there but I think the most important slide is this one first of all look at how male son look at ladies how male scientists are portray look at them yeah they're fat they're balls yeah Julia's clothes yeah anyway so here we have let's say the physiology and here the phenomenology and then this is the issue yeah we we can we can do the water we can do the wine and I hope I've shown you we can make some progress to seeing how these two per vary how one causes the other I think you should be more explicit here in step two yeah and I'd like to leave you with this question not on how the miracle is solved but what would be the miracle if I said to you actually I've just thought of how the brain generates consciousness I've now got the causal link what would you want me to show you what I'm going to show you is when you're performing rat is it going to be a brain scan is it going to be used suddenly feeling like me is it going to be a formula what's it going to be and I would defy anyone I've yet to meet anyone who has an idea even given infinite resources money future whatever what kind of thing would satisfy that claim because if I built a time travel machine you'd know what to expect if I built a perpetual motion machine you'd know what to expect but an idea of how the brain generates consciousness what to expect what exactly how does that report and go on to this inner person in a thing where does it stop so I think that whilst neuroscience can really deliver on understanding psychiatric conditions the romantic conditions the human brain in general it can help us look at correlations and appreciate the processes what we cannot as yet do is answer the miracle but I think we could write science fiction novels if we wished as to what kind of answer we might want to expect thank you very much panting thanks very much Sousa for a really erudite presentation we're actually going to protect you from the slings and arrows of questions for a few minutes and actually have an alternative forum a discussion panel and I'd like to invite our discussants as well as Susan to take the stage please how discussants firstly professor James Angus who is Dean of the faculty medicine dentistry in Health Sciences professor Rufus black who is marshal Government College and is also a theologian ethicist and strategic advisor professor Lowenstein who is a professor in the Faculty of Law at the University of Melbourne and Professor Philip Smith who is head of the school of psychological sciences so perhaps I can cut right to the chase Rufus black and you as a theologian and philosopher does this cut the mustard for you in terms of Susan's saying well consciousness is something which is quantifiable and from a developmental perspective is iterative and is that really iconoclastic for a theologian or is she talking about something parallel to what's really important to you is she talking about awareness and is what's important to you the concept of self and if so where do the two come together my task I guess is a modern liberal theologian is to make sense of the science and to try and connect it with the larger understandings that we wanting to have about the self and the nature of the nature of reality and the picture Susan paints I think is for a theologian extremely exciting one because it's an expected one now to some theologians it may not be but to a modern liberal theologian I think it is and these in a number of really important ways the first one is that modern liberal theologian expects that complex systems will emerge new States phenomena that are larger that are not the some of the more than the sum of the parts and the picture we've been painted here is a consciousness of something more than the sum of the parts it is actually an emergent phenomena from a complex system we see that in all sorts of other aspects of reality we'd expect it to be what consciousness was so there's one aspect of it which says this is deeply consistent with the way the world as a whole presents and what we'd expect the second thing is it says it's evolutionary which we'd also expect and celebrate and in lots of ways solve some complicated problems that theology struggled with which is how in a meaningful sense can we describe and I use the word kind of without a bit like avoiding the kind of defining consciousness how can we talk about animals and people both having souls and also our infant fetuses having souls but I think Susan provides us with a way of beginning and explanation which is to say the soul is the soul or the the enduring features of the mind is an evolutionary reality that emerges both in different life in different animal life forms and in people in an evolutionary in an evolutionary journey that explains provides a way a scientific way into a very very very difficult question it also explains perhaps one other piece which is important and it has an immoral kind of component to it which is once we kind of recognize consciousness has this continue this evolutionary continuum to it the nature of empathy and obligation to other conscious selves becomes something we can start to tackle in a really interesting really interesting way that I think in modern times as we've started to appreciate the consciousness of animals both theologians have always maintained animals have souls that that gives rise to an ability to join in a communion of some form with or without wanting to kind of be make any metaphysical connections between conscious beings and also holds out the possibility that the shape of the universe is an ongoing evolution that emerges ever higher-order forms of consciousness so if I interpret what you've just said it correctly you're sort of looking at empathy as a perspective of self in a societal structure and it's got an evolutionary dynamic and sense to it in that from a Darwinian perspective it provides a survival advantage would that be a fair view of what you say well I guess what I'd want to say is that for by whatever Darwinian means it might have come to be it emerges as a phenomena that's larger than the Darwinian forces that created it and therefore I think you know the lovely thing about consciousness as an emergent phenomena is it enables us simultaneously to say to not dispute the science at all but to recognize that this phenomena itself is not wholly described by the science and therefore we can look to it whether it is in ethical or thinking about the nature of beauty or truth or any other quality to have its own attributes that are not only describable by science and therefore a place for the humanities okay thank you Phil Smith your perspective you have a strong mathematical background and we talked about complexity here and a scientist sometimes we'd like to take a reductionist view of things what do you believe that computation and mathematics has to offer the field of justise then the preamble tracker that I strongly resonated with Susan's final conclusion which is not only definitely know the solution but just at the moment we don't actually know what a solution would look like so I am interested in neural computation the sorts of computational activities performed by neurons which I think are a correlation of Susan's neural assemblies as the basis for cognition for processes like perception attention memory and decision-making and I think there is a lot that we now understand about that for theory of nonlinear dynamics nonlinear systems we can talk in very sensible ways about the kinds of computations that the brain performs they're massively parallel plastic they are highly nonlinear and we can build systems which exhibit those sorts of properties which can solve complex problems in learning pattern recognition and classification so I see I'm optimistic about our ability to continue to further understand the kinds of computations that real brains carry out that can translate perception into action but that begs the issue of the qualia the subjectivity that Susan talked about what we don't know is why as a matter of fact when those computations are carried out as a brain within the brain within the bath of neuro chemicals that are is that the substrate and neural computation that that it produces something like consciousness and just just give a sense of why I am pessimistic let's do a little thought experiment let's imagine something like the Blue Gene project in Lausanne Switzerland where there they have brought the power an IBM Blue Gene computer to simulating a little slice of neocortex tissue with great neural realism great fidelity that everything that we know about morphology transmitter substances ion channels and all the rest of it now let's imagine that we could do this to something like the size of the whole brain as they aspire to do and let's imagine that that simulation started to exhibit all the hallmarks of intelligent behavior that it passed the Turing test it started following football team its it started to express prejudicial views about people who sing French songs in public trends on public transport we might start to treat that with a certain amount of deference and circumspection insight that it is seems to be behaving intelligently at least according to behavioral criteria of intelligence but the question then is it conscious I would argue is undecidable and this goes to why this is the hard question philosophically and why we don't as Susan emphasized at the end even have a sense of what the answer to the question would look like thank you all right well let's change tack slightly and James Angus you're in addition to being dean a pharmacologist and how does this resonate with you Susan mentioned so called modulators and their importance in the journey in relation to modifying our perspectives our arousal our consciousness etc you know on that continuum of awareness consciousness cognition cognitive enhancement where do we draw the line in terms of tinkering know what are the perspectives we should adopt who should make the decisions what's fair game and what are the demands on educators in terms of really empowering the next generation of health professionals in terms of how to deal with these contingencies which are going to be before us in the next generation and beyond well thank you trevor for those 20 questions let me let me start as a pharmacologist there is the axiom the knowing truth that every drug has more than one action because no drug has if it'll be improving to have only one action of course it's about the dose or concentration as to whether or not it will have the specific action you think it might have at that site so this is extraordinary complex and Susan was right to say that pharmacologists like to tinker an organ bars because you can control concentration and you can control the phenomenon because you only testing one thing and if you get a yes or no answer you've progressed if it's a maybe back to the drawing board so what she's shown for me today is that in this incredibly complex area when you start from intact man intact brain trying to go right down to the self the molecular submolecular level even what you're doing when you get down to that level is really increasing the power of the experiment the analytical power but what a pharmacologist has to do is not only be able to do that experiment if it take it back into the hole and that's where the pharmacologist working with the physiologist and the neuroscientist with the new techniques is going to add value but where should we start with these mind-bending drugs should we actually develop a drug for normal person and increase your memory let's say that's a hell of a call today because what is the assays fill up right this is what are we going to try and measure at the end and if it's a yes or no maybe you'll get there but if it's a maybe answer is just more phenomenon you haven't answered anybody's question should we have such drugs who's going to put them on the market who's going to do the science and I come back to the point is it's going to have a very different effect in probably every person who are normal to start with let's say forget about whether I have some disease and the simple things like just increasing your memory could of course be improved by your blood flow and if you fit that might be enough to give you that increased 10% 5% in your modulator that might affect increasing your cognate activity or your memory thank you and Lawrence keen is that a lawyer surely as these issues are a much much more deeply interrogated you know there are challenges for the community which emerge and I guess to which come to mind the end-of-life issues the question of vegetative state you know sort of the concept of when someone is actually deceased and a second is really a perspective of the issue of free will and predetermine ISM and where are we in turn of the legal perspective of this at this stage and do they need to be revisions which put in place as we prefer as we inexorably get a more fundamental understanding of the molecular and see their architecture of the brain well thank you for those questions I'm glad I get the easy ones to reverse them the law has in fact given a great deal of thought to placing responsibility for people's actions on people who do those things and so generally responsibility will not be imposed unless a person has acted deliberately and this is the the concept of the of the guilty minds so if a person is able to show at the time that they did what would otherwise be a crime that they were sleepwalking for example or that they were mentally ill that that would deny the guilty mind the the mens rea ur which would be necessary to prove as part of the crime and they would then be acquitted so there's a lot of jurisprudence on that issue but the second issue is the one where neuroscience is coming more before the courts and in the mid about 2004 and five when I was spending some time in Oxford at the Oxford Martin School then called the Oxford Martin 21st century school I went to a lecture by a neuroscientist to much I'm sure that Susan will know professor Adrian Owen and he described some work that he had done on patients where they were not they weren't sure whether they were in persistent vegetative state which is now in Australia called post coma unresponsiveness or minimally conscious State and this is very important for the more because the treatment can be withdrawn from a patient who's in a persistent vegetative state on the basis that it's not in the patient's best interests to to continue treatment that is futile so he took a number of these patients 17 and he gave them fMRI brain scan and to see whether they would respond to direction and if he asked them imagine playing tennis which is a motor activity this stimulated activity in one part of the brain and if he said imagine that you are walking from room to room in your house spatial concept that would stimulate another part of the brain so if I asked any of you to do this exercise this would be observable objectively by people who are able to do brain scans and he found that 17 of these people who might have otherwise qualified to have the treatment withdrawn responded to this test now that's very interesting in itself but it makes you wonder what might be the consequence of that and in fact I became very interested in this and wrote an article with some of my Oxford colleagues about the legal consequences of this because in England before life-sustaining treatment is withdrawn it goes to a court the Court of Protection and one of these cases had already arisen referring to this type of research that Professor Owen had done and the application was made that the patient who was otherwise going to have treatment withdrawn should have fMRI so has this is this something I mean even if it didn't if this were the case I think this is where the law has not really got going if this were the case that a person in this very modified way could respond to directions and had that degree of consciousness what is the significance of that and we could still say that even if that is the case it's still not in the person's best interests to continue the treatment in fact it would be better if we were looking at the association between that level of consciousness and general prognosis so I think that this raises real ciao for the law and we're only just starting to to consider them well what about the issue of premeditation versus irresponsibility and for example the perspective of a large frontal meningioma affecting that prefrontal cortex which Susan talked about and that I would have thought might be seen as 2012 as mitigating circumstance in terms of behavior if you could show that MRI scan with that five or six centimeter meningioma as opposed to the person who has a completely disrupted microarchitecture of the prefrontal cortex whereby the chemical structure is just change in exactly the same way but you can't see the differences macroscopically what do you see is the differences between the two and what are going to be the challenges for the future in terms of that dynamic yes well we've already had this issue arise with regard to a genetic predisposition to violence and there has been at least one case where in Holland where a gene was found that indicated that this person was correlated with this person being violent and so should this be a defense all the people in this family who had this genetic mutation had offended and were violent and the ones in the same family who didn't have us read lead good upright lives so what should be the significance of this it's the same sort of issue that you've just described and some people would say well if you know this you have this genetic predisposition and you could take this into a neuroscience concept as well if you know that you're a person of this type then there's an even greater responsibility on you to make sure that you don't put yourself in a position where you might be violent and so instead of being exculpatory it could either be irrelevant or it could make it even worse if you know that you have this predisposition those comments I throw it open to the audience now any questions of our panel particular professor Greenfield thanks very much Trevor and Susan thank you for having quite an inspirational talk about consciousness could I just explore that a bit further the issue of consciousness and the the relationship between consciousness awareness and we only just touched on itself and Rufus soul and you've I think got quite an exciting possible measure of of consciousness and we've got cruder ones I suppose like EEG with sleep and it's paradigm with anesthesia etc could I throw the challenge to you and you just explore a bit do you think there is a possibility that we could get some objective measure of self because I always think I love your idea that there's a continuum of consciousness so I always think the first cell must in two cells got together through the first synapse were they conscious and did they think of themselves as cells and they indeed do unicellular organisms now think of themselves as cells and if you could provide us with a measure of that I think we'd all be eternally grateful don't be what okay so thank you for that it's not just any old souls in neurons and I think that what you need is not just any old cell as in the amoeba but you need specialized cells that is to say neurons that communicate via the systems that we all know so I would suggest that once you have a kind of nervous system however rudimentary you have the potential for some kind of inner state that's sort of now obviously that won't be self-consciousness it won't be consciousness anyway such as we all experience but I think we can't exclude the possibility of some kind of sentient in a state even in the octopus or creatures that have nervous systems very different from our own or when those nervous systems are very early on in development so they would not have a sense of self of consciousness which let's be honest we could lose self-consciousness sometimes while still being conscious anyone who likes dancing knows that it's the depth knowledge you're self-conscious when you're dancing yeah so we all pay money actually to put ourselves in situations where we lose our self-consciousness now we let ourselves go we blow our minds we have a sensational time if I said let's go out now Jeff and have a cognitive time off we go I don't think that's what you're having no I don't know but yeah on the whole wine women and song drugs and sex and rock and roll which I would suggest our abrogation of identity however temporary the cream passing on now for example Oh in French oh those examples would be the small assembly mode so if you can sometimes not have an identity when you let yourself go that does suggest it's an add-on it's an add-on to ordinary consciousness and I would suggest that I don't is a larger assembly it's a larger it's just simply a bigger scale assembly of which most species are not capable but we of course are the subconscious I would suggest our subsets of an assembly that in themselves are not sufficiently extensive to dominate a consciousness but would contribute to it as indeed we know is the case so I'm quite comfortable with these subdivisions of assemblies accounting for these nuances in types of consciousness now with awareness again one can play around with the semantics but for those really interested one of my adversaries of the many addresses I have of course one is a guy called Christophe cork you may have heard of who focuses on the content of consciousness on what you are aware of and if you're interested in that debate in Scientific American October 2007 we wrote a joint piece where he and I set out our stalls in opposition to each other so he's openly I like it's quite and it's written for the general public so you may find that relevant because I already a slag off Christophe because he's not here it's not fair so you'll see his two things but my own view is that you can't talk about visual consciousness divorce some others and so on and the content of consciousness for me isn't as a higher priority or question when it's not high priority question as the difference between consciousness and um the hard problem that's what really gets me final question John finesse if we consider the blue-jean project analogy where we say that we can't decide whether the blue-jean machine has consciousness or not although it has many of the external attributes of having consciousness if we take that argument further we can say I could save the person there's to be I've never met before that I don't know whether she has consciousness I know I have consciousness all I know is she displays attributes of consciousness as I associate with consciousness but she might be an automated for all I know and maybe but but so I cannot decide on consciousness in another person except by analogy so I can decide in consciousness in a machine by analogy therefore consciousness it becomes a very personal thing that I can decide I can define for myself but I am NOT in the position where I can define it for any other person I think we're sticking with Philip and give Susan the final River um look I think you're exactly right John that's the reason why we are comfortable in inferring consciousness or in the person sitting next to us is simply because of morphological similarity now if the person sitting next to you was Susan's hypothetical Martian who was morphologically completely dissimilar but nevertheless displayed all of the external attributes of the intelligent behavior you would have precisely the dilemma that you outline and this of course gives way back to it's the it's the qualia it's the subjective the personal the private aspect of consciousness which are the things that have driven philosophers mad for centuries and which is why I think as neuroscientists or as computational model errs we can feel comfortable we can probably make a great deal of progress in future in understanding the computations probably the nature of the computations the size of the networks which are recruited in certain sorts of conscious states which I think goes back to Susan's size of neuronal assembly associated with particular sorts of conscious states but the irreducible there the bit that we have a great deal of difficulty getting to for the reason you outline is the personal private subjectivity Susan okay thank you for that well I'm not sure whether you're conscious or not but what I am sure of is if you are it's not my consciousness it's not like mine yeah so that's what makes consciousness so subjective and so special the cheering so but you are touching more not so much on the validity or otherwise of thinking that other human beings might be conscious but on the contribution and the non-exclusivity therefore of machines and I think one can approach the study of computers and robots and consciousness in in two ways either you can say right I'm going to model consciousness better model it in a computer perhaps that's one of the claims of the blue blue brain project now let's think about that what is a model a model is not a simulacrum it's you know if you want a simulacrum of a brain just have a baby so it's not or not so if you want to model something what you want to do is you want to identify the salient features to the exclusion of the extraneous ones if I wanted to model flight I would know that the thing I had to do the essential part of my model was to defy gravity and I wouldn't be too fast about incorporating beaks and feathers that's extraneous to the model of flight yeah so therefore if you're trying to model consciousness the problem arises what is the salient feature that we want to put in what are the extraneous features that we can leave out and I would submit we don't know that if we knew that if we knew what the thing was the salient feature to model consciousness frankly we wouldn't have to model it anyway because we'd have sold the problem all right so so I think that that's not very helpful now the second approach that you suggested is to build a non-biological device of enhancing and increasing complexity someone like Ray Kurzweil for example the advocate of the singularity people like that think if you have something is very complex then consciousness will just emerge as a product of complexity now one can't prove that's not the case because you can't prove something isn't the case you can only prove positives and the owners would be on such individuals to prove it was then you have the problem of the Turing test does everyone know about the Turing test yeah it's where from Alan Turing if you're given impartial access to a non-biological system and a brain and you can ask any question you like and through this impartial medium you have to evaluate whether the person's computer or a person and as yet no computer has passed the Turing test although there is a human being that's failed it which I thanks angel I think we all know people like that probably so so this this operational definition as I've suggested is very hard because even if you were given clever or things as you know you can just sit there the whole point of consciousness is not about responses or behaviors it's about what goes on inside and that I think is very hard to with absolute you know construct victim demonstrate in something that as John Searle the philosopher said might be built of old beer cans you know I think the thing that it's built of brain cells chemicals modulators integration with the whole body for my money those things are significant features I can't prove that they are but then the onus would be on you to prove with your beer cans at their conscious - thank you thank you well join your question made me almost bemoaned that we don't have Donald Rumsfeld on the panel just in compliment perspectives look we must end there and I'm sure you'd all like me to thank our panel very much for their contributions but especially to Susan Greenfield for the witty insightful and very instructive and erudite presentation thank you

Channel: The University of Melbourne

Views: 369,515

Rating: 4.8137741 out of 5

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Id: k_ZTNmkIiBc

Length: 94min 17sec (5657 seconds)

Published: Wed Nov 28 2012

Reddit Comments

[u/[deleted]]

I love this talk, and this emerging science in general.

[u/Hot_Zee]

good talk here but her new book, Mind Change has been mocked by peers. She doesn't do much science anymore, and too bad because she's an engaging speaker.

[u/[deleted]]

The Q&A was a waste of time, but the lecture was really good. Though, one could argue that it's not clear she's studying "consciousness" as much as "awareness." But, you have to start somewhere.