 Rydyn yw'n cyfnogaeth ei wneud arall y cwestiynau'r wrthgwrn arfer. Rydych chi'n gwneud i'r cefnod i'n gwneud â'r cyflwytoedd sy'n cyfaniaeth gyda'r byddauorydd ar beth sydd wedi'u ymlet aluminumau. Mae'r rhai hyn yn ei wneud â ei wneud ar hynny ymlaent â'r cyfanyddolanyaeth. Mi'n rhan o'r eu gwaith a'i gynnwch'r gwrdd bolig hwnnw o'r oedlaid o'i gwych. Felly mae gennych i gael y byd ei chael o ddau o'r pethau o'r holl o'r cyfaint. Mae gennych oedlaid o'r holl i'r Gwydiannau Nici. Nici'r profesiol o psycholoedau o Ycwyr Cymru. Nici'r cyfaint yn ysgrifennu ar y dyfodol. A chael i'n gwybod i ddim yn rhan. Mae'n gwybod i'r ddansflor. o'r ffordd ar y cyfnodd, Nicky yn Clif? Nid oes, rwy'n nhw'n fawr. Yw'r fawr, yw'n nhw'n nhw'n nhw'n nhw'n nhw'n nhw. Yn oed, yn canwndrum. Ar dwy'r fawr, rydw i'n gwneud yr mewn fawr, fyddwn sy'n yourr o'r fawr, o'r fawr, yn gyfan gwybod yr datblygu. Mae'r fawr yn ymgyrch yn ymwneud, is we'll displace what we actually saw and the way in which we saw it. And that's because when it comes down to it, memory is a subjective experience. We each see it through our own eyes. So it's not about what we see, it's about what we thought we saw in many ways on many levels. That's what becomes readily accessible again and we can change memory to suit the complexion of our thinking in different circumstances and at different times. Often at unconscious and subconscious levels. But it's also a shared experience. So despite individual differences in what we thought we saw and remembered, memory actually becomes a vehicle we use to share our experience with others, to compare notes, to question those realities, we can't quite be sure we've seen. And it's not just about thoughts we have of the past, it's also about things we think about the future. And so what we hope to do tonight is explore aspects of memory and mental time travel and we're going to do it using evidence from the science, sciences and from the arts as well. So what is mental time travel? Well, as we've hinted at, it's about memory of the past and it's also about the ability to think about the future and to plan for it accordingly. And in fact it has two fundamental features that makes it different from other kinds of remembering. So it's not just about information storage, it's very much about the self. And we're the creative self in that we're all the authors and owners of our memory. We make them for ourselves. It's so much more than just facts, it's how we see it through our own eyes. But it's not just about our own eyes, it's also about time with a time travelling self. We're very much aware that we can think about the past and think about the future. And yet at the same time be aware that we're in the present moment. And for that reason it's also the door to identity because our individual memories shape who we are and who we are shapes how we form our memories in the first place. But in truth you might think when we talk about memory we're talking about the past but actually we mean future identity for it's been suggested that memories really are more about the future than it is about the past. And it allows us to create multiple scenarios for what the future should be in the hope that we'll be better able to predict it and importantly to prepare for it. So mental time travel allows us to conjecture about alternative worlds that would have operated had circumstances unfolded differently. And to create new ones for ourselves that in truth may never come to pass other than in our imaginations and it makes us very special because we can indeed do this. So mental time travel this ability to flip-flop between remembering the past and thinking about the future in fact reveals two important points about memory. Remember future memory which will approach both scientifically and artistically. The first is that it's a poor sort of memory that only works backwards as the white queen so shrewdly remark to Alice in Lewis Carroll's famous novel. And the second point is that our memories are not simply repositories of the past that are fixed and never changed. Every time we revisit a memory we may later alter bits of it to suit our purposes always shaped by our subjective experience of the current moment that we find ourselves of the ever-eternal present. And I'd like to give you a reading from one of the books that we're actually using for tonight's lecture which explores this point in quite an interesting way and perhaps gives us a way of thinking about ourselves quite differently. So this reading is from the Moustachio Quartet and I'm taking a short reading from an extract from a point in which in this particular book people are at an art private view and there's an artist who has his work all around the walls right now in fact you might be here in this private view with your drinks and your hands can you imagine that? It's kind of a memory thing that you're doing by doing that. And you're wondering what the work's about it doesn't kind of make sense to you. It seems vague and strange but at the beginning of the private view the artist comes forward and reveals who he is, the complexion of his thinking how he assumes his place in the world and he says reliving memories and imagining futures is essential to all of our lives yet the very nature of imagination impedes and disorientates those same memories. It diversifies reality to the point where almost nothing can be known unequifically. As a species we make use of this to define multiple truths and so doing we keep reinventing our own past and anticipating our preferred futures both collectively and individually. The things all coexist side by side. Are we unique in being able to dream ourselves into imaginary spaces those places where our spirits would like us to be seen travelling mentally in time in the direction of our own choosing? I suspect not. Are we the only ones in a turbulent universe to question the ontology of existence? Now there is a question. For me painting is not about art or an artefact or a book in which characters might only appear to exist. It is the encounter between the conscious mind and the worlds it locates in its perception. I have discovered this if there is time we are it. Take me apart and learn my constituents and you'll realise I do not truly exist only your prejudice in this moment refuses to allow you to accept the truth of what I say on behalf of all of us. We wonder about ghosts. We all are. So how is mental time travel studied by scientists? Well the brain network is activated during mental time travel. It's shown here and it includes various parts of the frontal and temporal and parietal lobes but the critical area as pictured on your right is the hippocampus that seahorse shaped area. Now if you don't know where it is if you take your fingertip and imagine placing it on both sides pushing it in about two inches from the top of your ear lobe then your virtual fingertip would be touching your hippocampus so that's where it is. Don't try this at home perhaps. It could be quite messy. Anyway the interesting thing is destruction of the hippocampus not only destroys the ability to remember past events but also the ability crucially to plan for the future. Let's now consider the eminent English musician Clive Waring. Stick your hands up if you've heard of him. How many people have heard of him? Just Clive Waring. W-E-A-R-I-N-G. If you've not heard of Clive Waring this is going to be very interesting. So he actually studied at Clare College in Cambridge which is actually where my college is. And the thing is his hippocampus was irrevocably damaged as a result of a viral infection. So you know the herpes simplex virus that usually it just causes a nasty little unpleasant console around here. Well if it crosses the blood brain barrier it's really bad news and it completely destroys the hippocampus. So as a consequence of this his episodic memory was completely destroyed. So if you google it on YouTube and you google the man with the seven second memory his name will come up as the hit. And certainly he can barely remember things for you know seven seconds might be an exaggeration but frankly for no more than 30 seconds. And without a permanent marker of the past the interesting thing is it affects the present because then the present has no anchor. It's nothing to hold on to it's just a series of thoughts that pass by on the tide and they just float away into oblivion. Allow us to show you an ever such a short clip of just how debilitating his memory problem was as a result of this hippocampal destruction. Here he's being interviewed by his wife Deborah Waring. I've been here about 10 minutes at least. Well I've no knowledge of this. My answer has started working now and I've seen the whole thing I've been seeing in English. What is that? And do you feel absolutely normal? Not absolutely normal no. Completely and completely confused. Confused? Yes. If you've never eaten anything, never tasted anything, never touched anything or smelled anything what right do you assume you're alive? But you are? Apparently yes. But I'd like to know what the hell's been going on. Thank you very much Nick and Claib. So we're going to continue with another performance. This time from Chris Rawlins who describes himself as a memory performer. So could we welcome Chris please? My name is Chris Rawlins and I remember things. So we go through the house we go in the front door we could turn right into the front room we could then turn right into my bedroom which was on the ground floor but we don't go through the kitchen out the back door down the patio through the bush which is impossible but I do it anyway because it's my own memory I can do what I want go me and I go back to the river out which is at the back and on the river I can see this arrogant kind of fat oafish swan looking at me but it's getting closer and closer to me so this will be swan close is that the street name? Yeah good you seem shocked that's what I'm here for. What most people tend to do is to write down a phone number so it starts with 07 so I always get the couple numbers at the beginning for free but you haven't you haven't done that so thanks got a pen see my pocket excuse you oh you know when you to the front a little bit I just hold the paper up for a second so I definitely don't see it as well um same with the zero if you dot the page it's no longer a fresh page which is annoying and now it's bled through to the page underneath which is even more annoying um hold this facing out this is what I've encoded the number to mean hold it facing out um we have I can't write today I'm sorry did you know in the numbers you've written down and by the way you didn't show me this piece of paper no uh you said you were doing an internship and this is your last day um and as a result you were eating as many sandwiches as you could um it's true um um so that the tray that's gone missing out the green room uh no not true but uh you you did it we I'm just saying we haven't met before you you actually worked here up until today we were out to finish so I hope you do great things after this um but you know that I haven't seen the piece of paper up until now when we're on this stage you kept it a complete secret and I even stood in the corner of the room like a like a dunce which is a guest quite fitting I'm not sure um would you read out nice and loud and clear in fact before you do I was just about to say did you know they're exactly I'm looking at now so I can really cheat I should have just excuse me done this myself uh five odd numbers in the number that you've written down I think is correct will you check make sure that is right five odd numbers yeah and if you take those odd numbers do you remember the Nokia 3310s the old phones with snake on them yeah snake's terrible but the phones are great if you get one of those phones and punch in the five odd numbers and check this when you get home and it's been filmed so we can check this uh you can very nearly make the words not quite but very nearly make the words if it's on predictive text monkey letters are in the wrong order but you can rearrange it uh almost uh I live a sad life you're going to read out the numbers on your piece of paper the one that I've only just seen for less than I think it was less like 1.8 1.9 seconds we can look on the camera later maybe nice and loud and clear what were the numbers that you wrote down spot on hang on I'm so sorry that I've gone over but I need to I want to do this last one as well um if we take these numbers I said this is what I'd encoded your number to mean so what my brain does sometimes not all of the time what it does especially with serial numbers is look at a number and shrink it down to two digits I don't know why um and I'm not very good at maths but this is this is what happens so if we take feel free to get your phones out if you're good at arithmetic just do this in your head if we take all of the numbers here and add them together you will actually find that 57 is the total of these numbers the number that I looked at for less than two seconds I'd say 1.8 1.9 second and with that you can leave and go back to your seat and relax and eat lots of sandwiches on your way out go give her a big hand for helping so finally we come to this gentleman here uh you know that I've not seen that piece of paper we sat actually in here it was nice and comfortable um you actually uh thought of a word it had to be in the dictionary had to be in the English language it was a real word and and I asked you to let me know if if if it was going to be like a rubbish one and make sure it was a good one and you promised me it was a good word so I hope it is uh and I actually gave you a single sheet of paper with a with a pen that writes in black ink was in my pocket it's not there now and and then you printed the letters from the word in like I asked to do it in like a scrabble kind of way in lots of different places and then I gave you a pencil a little golf pencil uh which I've actually left somewhere I hope no one's sat on it a golf pencil and you filled in the rest of the little box with what I said random shapes numbers doodles anything that you want um but what was important was that it created like a code like a puzzle that I'm going to try and work out in a second so you're going to hold the piece of paper towards me but not just yet because when you think about it numbers in a string of numbers because each each individual number can only go up to nine there's only nine different variables so letters of the alphabet have 26 different variables per letter of the word that we're using um but to make this a little more exciting and hopefully a little more impressive I'm going to do this with the paper upside down so not only does my brain my mind have to take a mental photograph and hopefully less than one second I have to store the image flip it on its head zoom around the image as if using like an iphone screen to then piece together the word that you're you're thinking of whilst at the same time in less than one second trying to do one other thing before I leave you all um so if you don't like this same as the the thing with the map just uh just clap anyway paper facing towards me writing upside down upside down facing towards me if it's facing towards you I won't be able to read it and I'm I'll be in a sticky situation but and I can't have you count this time just any paper facing towards you and if you could go to stand at the front of the stage over here face the front in your word there was a uh letter o there's a zero well it's not a zero but it's letter o is that correct yeah good um there is a letter I think it's a repeated letter it's a letter b you um and don't take offense your L's are weird uh there's an L in the word I think your word in less than a second I think it was 0.8 of a second um feel free to check uh was and is first half page 132 top left in the dictionary it's the same guy so you're going to come to every show I do um would you take this for me so it's a dictionary and good catch dictionary and theosaurus so there are thousands of different words in there we go to the first half that's what the fh stands for page 132 the one is kind of blurred into the p but my writing's bad page 132 first half top left uh if you could tell me in a nice loud clear voice what word is there at the very top and what was your word there you go thank you so much for your help thank you so so much thank you so much for listening to me um it's been a pleasure to be here my name is Chris Rawlins and I remember things good night the next speaker is um Hugo Spears from UCL and um he's the uh head of the special cognition lab there so this is a lecturer this is the end of the night where I'm going to um provide information going to embed in your brain facts I'm going to have in fact three graphs tonight so we'll get on to graphs in a moment um so tonight I'm going to talk about memory and space and in fact I'm going to start with um oh not with this slide projector um with these these people out here so London wouldn't really be London I think unless it had these creatures prowling round its streets picking up customers and performing magic feats not far off what we've just been having and I can imagine you stepping into a magic in a cab one of these cabs later trying to get home and asking to go somewhere and how many of you in the audience would clap rorously for that expert you know amazing ability I suspect not you've been clapping away to some really very impressive Chris but what is it that makes our London cabs so special is that you can ask them to be taken to somewhere deep far in the south of London they will complain but they will eventually get you there and that is because they spend about two to three years studying the 25 000 streets of London so they do pretty much like an undergraduate degree on that and that's just the six mile radius around Sharon Cross so that's the topic at the beginning of tonight's last rolling moment with no tap dancing just facts first fact is taxi drivers are amazing they are world-class and in fact in 2003 their brains won the ignobell prize for medicine because it turns out that these chaps and here is here is three of them swatting up over three years three of them sitting in a a school learning their brains are not normal they're very unusual do we have any taxi drivers in tonight okay I can make very different jokes given that so their brains are not normal and we know this because Ellen McGuire at University College London not far away from here looked deep inside their brain using magnetic resonance imaging and she measured the brain this is another you saw earlier Nicky put up a picture of the hippocampus in various other brain areas I've now stolen the image from Wikipedia under hippocampus which is the skull rotating where yeah you don't have to put screws inside your head to see but that red structure is the hippocampus and it's it's not normal in taxi drivers so the posterior part towards the back of the skull that gets bigger and it gets bigger the longer they've spent driving a taxi through London so this was discovered in 2001 this ignobell prize and so since then so the question is why why did taxi drivers have this bigger hippocampus and because you've seen the earlier talks tonight you can probably guess it's because of that memory that we know this structure if you damage it like in Clive Wirings case you can't recall memories so this evidence that this structure gets bigger in taxi drivers is amazing so not only are they amazing at this memory feat of getting you home tonight anywhere in 25 000 streets instantly they can't hang around on a street taking even maybe three seconds to think they've got to do it otherwise somebody's going to scream they'll probably kill a cyclist it's something like that but we know their brains are different now in 2006 we thought well let's pit their brains against bus drivers now we'll do an experiment to see if bus drivers brains are big as well and we found out bus drivers brains are really boring they're just like yours so bus drivers here's a map so there's one of these this is the first graph the next graph some were interesting because there's a hidden component in every graph and see if you can spot what that is before I say ah and the secret is this is a normal graph so what this is a graph showing us here is this is the facts um how long a taxi driver in years going up to 30 years they spent driving in London each one of those dots is a London taxi driver along the other axis at the bottom is how big is the back end of their hippocampus and you can see scientifically we can measure this as a yes that's not by chance we've got this something happens in their brain the posterior hippocampus gets bigger and you saw that little movie earlier about the squirrels weirdly enough squirrels posterior hippocampus gets bigger too but seasonally so when it goes into winter and they need to store more nuts their hippocampus gets bigger but when summer comes it shrinks back not for London taxi drivers for some reason but it doesn't matter bus drivers just don't show it so it's something about not just driving through London dealing with annoying customers soaking up all the traffic fumes it's something about the knowledge of London that's important so that Ellen McGuire and Katya Willough who are involved in this did one further experiment I'll just take you into which other was really nice clinching one they looked at what happens when you acquire the knowledge so Chris said he spent how many years was it Chris he spent the those books yet on the map books right so three yeah so three so what this study was will take people like Chris who well who decided they want to become a taxi driver not to similar they want to memorize that book the London AZ will take them when they just want to start out they don't know it like a magician's trick will take a bunch of people that don't want to do that but a match they're equally you could have just picked between them and will scan their brains will measure every little bit of their brain using magnetic resonance imaging and will measure that and then we'll come back three years later when they pass their test and see if their hippocampus has magically got bigger and we'll see so this is the graph here so what you can see on the right are controls the scientific where people who just sat around doing nothing they could be doctors they could be dentists they could be people shooting lions or anything but they don't change their hippocampal volume but look at these taxi drivers thankfully for Eleanor who'd spent enormous amount of money scanning them there was a nice effect that their hippocampus got bigger so there's a hidden part of this graph and you might have seen why these bars separated and that's this part what happens to the people who spent three or four years studying that book endlessly like Chris but can't do that magic act they fail the exam nothing their brain their hippocampus doesn't expand so it's not just sitting down with the book every day but it's actually acquiring that knowledge that seems to drive the hippocampus so since that those early studies with Eleanor and I was involved in scanning taxi drivers I wanted to know what happens to you what happens to normal people's brains as they acquire a little bit of the knowledge I wanted to go out and I wanted to use magnetic resonance imaging like Eleanor'd use but instead of measuring the structure in their brain I wanted to measure what is it doing how is it being used so I'm going to use something called or just stick the word functional in front of magnetic resonance functional magnetic resonance imaging we can look for where the blood is going in their brain to see where activity patterns are occurring here's somebody going in an MRI scan and here is the reconstructive brain of one of the taxi drivers I looked at but for the study you wanted to do we decided we were going to look at how people navigate through space how do they actually move through space it's a real big problem trying to take that object around London secretly and strap it onto people's heads it just doesn't work so what we needed to do was take London inside this object bring London into the MRI scanner so with a lot of fun there have been all sorts of attempts to do this people have used virtual reality for years and we thought no let's take a film crew let's shoot an entire bit of a city and we'll go at five a.m with a steady cam crew and film the whole of a bit of London and piece it together and that's what we did we pieced together a whole bit of London and people came in so we got people to go around this bit of London learn it somewhere they'd never been before or claimed they'd never been they made them do a knowledge test before we made them go around on a very specific tour they had to memorize these streets only if they passed our exam not far off what Chris had to do like at this reference point how would you get from A to B they had to do that our subjects passed this test and then we could scan their brain the next day whilst they navigated through this film footage of London but the big problem we had was thinking well that's all great but where do we pick in London where are we going to choose to set this crazy experiment and in fact we settled on a place that was linked by these four men so this is my participation to you this is a bit of London that links these four men can you tell me in the audience you've all been warmed up very nicely with a bit of dancing and a bit of theatre but who are these men shout out to you recognize yeah that's the normally the first one Karl Marx and a bit more advanced sorry Francis Bacon very good it's Mozart excellent yes wow so this is the first time I actually got an audience educated enough to know we have on the right Francis Bacon Karl Marx normally the beard gives it away Mozart people don't normally get and Samu Johnson so what is it that connects these four men well they all spent a lot of time rolling around cruising this bit of London London soho so this is a bit of London that there was all sorts of coffee houses and all sorts of places of ill repute that they would venture into even in Francis Bacon's day he was he was well known to roll around but this is a bit of an odd map so we picked picked this bit because really is a warren it's a dense street if you want to test navigation you want to put a taxi driver through a horrible test that's your bit but does anyone recognize that map another little memory test John Snow's map so again twice tonight it's a very educated audience tonight the last time I gave this talk was in it was in Santa Fe so Vince saying you never get out I only go out to give little talks I went to Santa Fe and the entire audience leapt out of their seat there's a geography conference so they all know this map backwards so this is the map drawn by John Snow in the 1800s and there's the earliest kind of epidemiological map it's not a very nice map because those dirty smudges of black in it are deaths from cholera and so John Snow started to map out he kind of assessed that everyone was wrong in the medical profession and said to map out in this bit of London where all these deaths were occurring and noticed that there's a hotspot right in the middle of this map and that was right next to a well which is still there just down the road so if you pass by there's a well there and it doesn't have a handle and that's because John Snow stole it he took off the handle and the deaths from cholera dropped dramatically so it's a remarkable story of this lovely map and I'm now going to sort of look at how the brain maps the space I'm not going to look at deaths from cholera but how does the hippocampus do that and so actually I'm going to go to the last graph of tonight which is about how you remember the past going back to Nicky and Clive Store how you remember the past the plan for the future so you're able to scan people's brains and we reported last year an enormous number of things that would take up all night to talk about and I talk about one of these which isn't in our published paper so this is new data no one else in the world has really seen but it's kind of fun so we're interested in how people plan how they use the memories of that environment to plan for the future so what we did very carefully when they walked round on this tour and had to learn the knowledge was a very particular tour which meant that when they were tested in the scanner they couldn't remember the exact sequence of streets they'd been through they had to reconstruct and judge journeys across it so they had to really plan they had to use the memory to construct something they'd never done before and after they so at the end of the scanning we can test how good their navigation was so then the audience from guessing some of you would say you're quite good at navigating a good memory for space and other people would say you're very bad and you might think well that would explain maybe the hippocampal activity like taxi drivers are really good so people who are good at navigating should be really good at planning for the future that's not what we found hippocampus and the brain we look at the activity isn't that excited by good people but here's the trick here's what we did different was that at the end of the experiment we got people to come out of the scanner they thought it was all over and oh no we gave them a cup of tea and made them watch everything they'd done again in the scanner this time we asked them a memory question we said okay watch over this footage here you are walking past the john snow pub do you remember what you were thinking about then do you remember what you were planning to do and a lot of the time people said no I have no idea what I was doing but sometimes they go oh yeah there's crepe affair at that point it all came back to me and I filled in this route and people vary a lot on a scale of how obsessive they are about picturing their way through space uh and we find that's totally unrelated to performance if you have someone and you leave tonight and they start rambling on about all the exciting things in the journey ahead it doesn't mean they're going to be good but they just may be engaging it so what we thought we'd do is look at how does that thinking about the future thinking about the streets on this graph relate to activity in the hippocampus particularly that bit that gets bigger in taxi drivers and I wouldn't be showing this otherwise except for this graph that we find and these little dots of black dots are each of the people we studied and not deaths from cholera in this case so there's a there's a graph here and you can see actually the more you obsess about the future streets ahead of you the more you're engaging that bit of the brain it seems very likely our london taxi drivers are obsessing about these routes ahead so those of you've got good eyes and you've not drunk too much gin and you can see you perhaps see that there's not just entirely black dots on that graph there's one that's different a little red dot on there and normally under ethics you can't say oh this is john snow dot number one but in this case we can because this chap gave his permission this little red dot is the writer and broadcaster will self who we thought this guy writes obsessively about psycho geography and space where on this scale will he fall and indeed he just pips ahead of the most most obsessive student he is by far the most obsessive and very happy for me he lies pretty damn on the line we predict his brain activity so will self uses his hippocampus more than average telling something about how the brain is using he probably has an unusual brain but we haven't had time to look into that but if you want to read more about will self's brain do go and buy a copy of memory in the 21st century a book on written by literary critics and artists including a chapter by myself on will self's brain