KEXP Presents Mind Over Matters; Sustainability Segment: Sebastian Seung

this is diane warren your host on the sustainability segment of mind over matters and he xv seattle ninety point three fm an online at atx the data orgy i guess this morning as sebastian song professor of computational neuroscience in physics at mit an investigator at the howard hughes medical institute sebastian has made important advances in artificial intelligence a neuroscience his research has been published in leading scientific journals and also featured in the new york times technology review any economist sebastian stein is here today to tell us about this book connect on how the brain's wiring makes us who we are published in two thousand and twelve welcome thanks very much and have a beer what exactly is a connect on a connected home is a map of the connections between neurons in your brain if you want to imagine it you might think of a map that you find in the back pages of in flight magazines imagine that every city in that map is replaced by a neuron and every week between two cities is replaced by a connection between two neurons connect neurons important they're

important because they really provide the physical basis for your mind so i love the fact that the title of your show is mind over matters and indeed the relationship between minded matter has been something that philosophers and wondered about for a long time and there are scientists are making progress that connect them is the map of the network which supports the activity patterns the little signals a chemical signal to circulate a nurse i just think that's the function of your mind in the book you make the statement you are your connect on would you say more right so imagine that map in the back of the in flight magazine your map is much more complicated looking i gave you the basic idea by invoking that metaphor but imagine a map that has a hundred billion cds and it has ten thousand flights coming out of each city that we're connect them is like and the hypothesis that theory scientists have is that your memories are somehow stored inside that pattern of connections between neurons that every perspective was unique and so your individuality your personal

identity beyond memories may be intelligence maybe a mental disorders were somehow included in that connect them we can comment on the relative importance of genes in the structure of connected rooms well connect those are really important because they are influenced by both experiences and jeans so every time that you have an experience the pattern of connections the flight map inside your head that gets modified and people think that's how memories are stored but at the same time genes also have an influence on your connected and we had that debates about those jeans experiences thing for a long time that we all know that people often resemble their parents not only in their looks but in the way that they behave and we've had big arguments about whether that's due to upbringing or due to genetic inheritance but scientists all except the idea now that both are important both jeans and experiences have an influence on the mind and the show is is to go beyond these kinds of philosophical debates and answer that

question precisely how do experiences have an effect on your brain precisely how the genes have an effect on your brain that's how we need to make progress no jeans have an effect on your brain in many different ways but a powerful way is by influencing how your connect term is created during brain development when you're a kid when youre young child or even in the womb there's a lot of complicated steps involved in wiring up the brain the neurons have to be born but hundred billion neurons and they have to migrate to their proper positions are in a complex dance and then they send out branches you know the neurons that like trees or they send out these long beautiful branches which untangle the intertwined and at points where they touch they can make these synopsis their special junctions winner of communicate and that kasich is a connection so genes affect our brains powerfully because they actually died all these prophecies of brain development her flat is the structure of our connect times how much did they change over time oh yeah that's a big question that everybody was silly answer

to so we all know anecdotally at least that it sometimes seems hard to learn things as we get older so scientists of hypothesize perhaps you connect town doesn't change as easily as you get older but the evidence for this has been hard to really nail down precisely there are four mechanisms of connect them change that scientists have identified i call them before ours re waiting we connection rewiring and regeneration we waiting means a change in the strength of an existing connection so it's a re waiting would change how effectively a connection transmits a signal from wander onto another that's the most minor kind of change in effect re connection means the creation of new synopsis or the elimination of old ones then rewiring is the growth of new branches of neurons or the retraction of those branches and regeneration would be the creation

entirely new neurons or the elimination of older ones it believe it re waiting happens throughout her life lifelong learning is enabled by the fact that re waiting is possible even when you're old you can always learn new things re connection was thought to stop adulthood in the nineteen sixties but it's now known the re connection also continues an adult so the battleground has been about rewiring and regeneration and in the eighties and nineties there was a lot of impressive evidence the rewiring stopped in adulthood which could explain why we can't learn things as well but these days there's a revisionist the rebels who are fighting new evidence there even rewiring can occur in the adult brain such a controversial subject what is known about what causes can and towns to change so that's been investing in the most for the case to re waiting there's a famous idea that when two neurons are active simultaneously that the connection between them get strengthened so

you might imagine would say that i have experience in that experience is activating some ensemble of neurons inside the brain then afterwards that ensemble is more strongly connected to that experience and the hypothesis goes that those stronger connections cause is to the physical trace of the memory that's been stored now what's driving the other prophecies who knows and the waiting is also weaken ios apps is it maybe that was announced that weakened progressively eventually it just gets limited that's a reasonable hypothesis but hasn't really been proven what is known as a solid fact about learning well we know that the re waiting connections occurs in association with learning we know that it can be triggered by activity but it's been hard to see the entire pattern of connections that gets created where we store memory that something that but my lab that other labs are going after was trying to develop new technologies for

seeing connect terms so that we can actually see memories literally see the material basis for stored memory inside the brain and how do you propose that would work oh i should explain that kind of steps required to find collectibles i've talked about that connect them as this map that resembles an airline route map how you actually get that from a real brain and this involves some interesting technology is the first step is to do the brain you have to him as the brainy extremely high resolution because the branches of neurons are so tiny they're so thin that if you don't look with us official resolution than it does with its toll and terrible mess so we use a technology called electron microscopy which is a i guess they're keen is kind of my cross to be the note it's it's i'm much more high resolution than even light microscopy which you probably using her high school biology class now it's not enough to get to use an electron microscope because brain tissues three

dimensional so the first thing that we do the brain and this is with a dead brain we take it and we cut it into extremely thin slices with a high tech version of a deli slicer it's fitted with the world's sharpest knife the diamond knife and we cut the brain into slices that are a thousand times thinner than a hair a new image it and once we emerged although slices we have become a virtual brain a three dimensional image of all the neurons and all the senators inside the brain and now if you wanna find a connect him we have to go inside that image and trace out the pathways all those branches take and final the synopsis and then we can map out those routes effectively become like the roots that the neural signals are taking and that's how we define the connect them that's a time consuming process and we're developing advanced computer algorithms for doing that automatically and we're also asking people to come help us because computers aren't smart enough to do this act really really actually we need people to oversee the activities of the artificial intelligence and there's a web site called

high wire dot org you it wired dot org where many people who are interested in learning about parasites get the opportunity to do your asides discover new things about the retina which is the shiite girl tissue at the back of the eye i'm diane warren and my guest is the best insight and author of the book connect on how the brain's wiring makes us who we are and you are attuned to the sustainability segment of mind over matters and t x t ninety point three of them and on the web add k e x key pad o r g what can connect comes tells about disorders of the brain oh yes so clearly one of the reasons to be interested in the brain is just curiosity but another practical reason is that there's a play ways in which brain scan not function the way we want them to sew mental disorders are a big problem for our society now there some kinds of brain disorders in which we can clearly see that the

brain is falling apart and all summers disease or parkinson's disease if you look at the brains of people after death during an autopsy and you look through a microscope you can see jon cooking lady inside neurons and accusing iran is dying there's obviously something wrong and that helps guide research toward finding could treatments but in other brain disorders such as autism or schizophrenia the neurons look healthy if you look at the brain's it's hard to find a clear and consistent abnormality you might find abnormalities in some people but they're not consistent across different patients which suggest that there's abnormalities or just a sink it you and i might have and are not necessarily related with the disorder itself so this has been a huge puzzle how come people with autism schizophrenia behave so differently and yet we can't find something obviously abnormal about the brits and in fact it return acceptance of

schizophrenia as a brain disorder right so for years people did not want to accept the idea that it was a brain disorder and i think only in the last to serve twenty thirty years as the public come to accept his ideas so what could be wrong with a brain well i think about the back of your stereo system all those cables going back and forth between the components if i were to <unk> mostly go behind your stereo and switch around some of those wires your stir it wouldn't work anymore but if you just casually glanced at the back of your stereo you would notice anything wrong it actually have to trace the pathway of one cable from one component to another component so the same thing might be true about the brain either the neurons are perfectly healthy in these disorders but they're wired up differently baby business wire into the brain or we call them now connect top of these so a big all of my research is to search for connect top of these i think i'll be really important discovery if you could find them and to help guide research toward

treatments when some of the evidence that suggests these content properties actually sands well of course we haven't found them yet so it's really in some ways just a hunch but some abnormalities statistical abnormalities have been found so for example we know that autistic children on average tend to have larger brains than regular children at a very young age maybe on average at ten percent larger gray now that's a statistical abnormality it only as a parent when you examine average is if you took every kid with a big head and said i can't is autistic that would be woefully captured so the average offenses in size though suggest that there must be some difference in structure right and maybe if we have a more refined measure a structured insight sizes such a crude measure structure if we have a refined measure organization we might be able to find abnormalities it working for what are your

thoughts on how that connect homs hama stakes in connections within the brain can be fixed oh yeah so the obvious question would be a surprise that you found indeed that one of these mental disorders has caused by miss wiring of the brain then would mature require fixing the mess wiring that's true and so in the end who won a cure i think it'll be necessary to harness the brain's natural capacity for plasticity where the brain naturally has abilities that change has mechanisms for connect them change so there must be some way of using them and maybe we can develop drugs special technologies for turning up the brain plasticity if you could imagine that maybe we've become less plastic as we get older but there maybe drugs that can enhance the plasticity and those roads could be important i'm just speculating but they could be important for treating mental disorders in your book you mention that thought that some antidepressants could act through connect homs would you expand on that that's a great that's a great question so the story of anti

depressants is really a very interesting one amazingly they were discovered by accident it turned out that these drugs that have the effect of making people happier and then only later on was it discovered that these drugs altered the level of certain nerd transmitters so sets a serotonin serotonin is that it's a chemical that secreted by neurons to signal to each other inside the brain so the natural theory then grew up to explain why antidepressants work the theory said that well maybe people who are depressed don't have enough serotonin and antidepressants are fixing that by increasing the levels of certain that's a very popular theory of nor transmitter in ballots that theory remember was made up after the fact and it's not really even clear that it's correct it's just a hunch and one difficult fact explain is that antidepressants typically take several weeks before they have any effect on mood and yet they change their transmitter levels effectively

immediately so an obvious kind of hypothesis would be that actually these antidepressants by cheney's certain levels they are now changing the ability of the connected to change and so some kind of change occurs in the brain over the next few weeks and it's that change in the brain which then cause a change in that but you go into some more detail about how experiences actually change the brain in and what things are most important are changing well i want emphasize here that that i'm approaching this with a sense of humility that come from knowing how limited near a seismologist about change is that one of the reasons to study can attempt is precisely because we've been frustrated in our ability to know exactly what happens in the brain when we learn something new when we recover from a brain injury i deserve particular kind of the chains of you like me to address because the answer might be different for different kinds of changes with a change in behavior you're trying to improve yourself in someone read well i guess the

biggest change that we you wanna make is changing a bitch or patterns of behavior right that we maybe smoking when they get angry too easily there may be certain habits they're somehow ingrained in us that are very hard to change so natural patterns of behavior are presumably due to pathways in the brain that have been created they go from one or onto another so stimulus response pathways right so you see a cigarette and then what you wanna do smoke the simple answer of how that happens that's given binder scientists is that their son visual neurons which are activated when you see the cigarette and those are connected to some pathways to other neurons which then make you wanna smoke so it's a difficult question to know what exactly is happening when we try to break those habits are we somehow trying to weaken the synapses that are involved in driving that pathway behavior or is there some other part of the brain which overrules that behavior so i don't know that we really have any kind of fundamental

answers about how that happens i would guess to both are actually happening but the overall idea maybe more correct because we all know that it's easy to relapse but the fact that when you give up smoking and let's eat about smoking for five years and then all the sudden if you start taking a cigarette again you feel incredible earth and then you start to smoke and the old behavior comes back so that suggests that the old pathways are never truly gone away you're listening to the sustainability segment of mind over matters on k x p seattle ninety point three of them and on the web at atx peanut allergy i'm diane warren and my guest is sebastian simon author of the book can and tom how the brain's wiring makes us who we are would you come in on the need for new technologies to study that connect on hypothesis you alluded to that a bit earlier yeah so the new technologies are needed because the brain just has a fantastic weekend triggered structure most people are familiar with mri machines the machine that enable you to look through the skull of a person and see a

living brain and those are fantastic new technology the timbers of the last few decades but most people are aware that the resolution special resolution of those emerging methods is really crude so let's say that one pixel an mri picture it might be one kilometer on assad but one millimeter of brain my container hundred thousand neurons and a billion connections between neurons so you've got a whole universe inside that one two millimeter and you'd never see it if you're looking to mr what do you think is the best approach to that i understand connect towns while the person we're taking really is to try to improve our technologies over time and actually be able to map the connections completely so in the past people attempted methods that mike napoli a few connections a whole whole complicated network but we're hoping that our technologies will steadily improved over time and enable us eventually to map all connections inside

actually heir or maybe even all connections aside an entire brain and what kind of time frame do you predict for this project how well that's a great question so how long it would take for technology to progress to the point where we could do an entire human brain further apple well we would have to be optimistic i would be optimistic hear a lot of that depends interesting me on the progress in computers said two kinds of technologies required imaging to be the images of the brain and the second one is analyzing the images and finally connect come from them the second step requires computers and you know the computers have improved at an incredible rate over the last fifty years so if we all domestically assume that computers will improve at the same rate the same my oppressor record they've been improving in the past then maybe another forty fifty years we would be in a position to find entire human connect those without too much difficulty in your book you proposed that death is the destruction of connect homs would you say more

well that's just a natural outcome of the earlier statement that you or your act if indeed your memories are included in your connect them then ultimately death is really about the destruction of those patterns of connection destruction of that information it's not really about your heart stopping or you're breeding stopping it's really about this destruction of information and makes you you so that's the motivation for the concept of connecting death and in your book you mentioned a few examples of people being pulled down in the effect on their memory that sort of thing would you like to sign more oh yeah those are fantastic stories occasionally there to the terrible accidents when people fall into icy waters and live submersed at the bottom of a lake frozen lake for maybe forty five minutes and during that time the temperature of the body drops so low that most chemical process these aren't

really slowed down so much they basically stop and so there's no signal circulating your brain there's a heart pumping the circulation of the blood and sometimes these people are pulled out of the water and somehow they survive and not only do they survive the amazing thing is that their memories are largely intact they might not remember what happened that cause them to fall into the icy water but the memories of their whole life are essentially still preserved so this this is an important observation because it says that the activity of neurons the signaling of neurons that's very dynamic that's not necessary for long term memories that long term memory seem to be stored in something more stable and that's this material structure in the brain and the connect helm is really the summary of them to rule structure what do you hope your book will accomplish yes that's a great question right because you're asking these are why did i write this book and its important question because rania book is hard work and sometimes painful it's like being assault her confinement almost

the paradox of course is that you're trying to bring a message to the world you get you have to spend so much time alone well india i thought about this as i wrote the book this many different reasons one of course is to just communicate excitement and are assigned to the public and the second is to inflict my colleagues to argue for a particular way of doing our science sighs untouchable seemed like a drawing thing but in fact if you talk about the frontiers of knowledge and how should we go forward scientists often have a lot of disagreement different opinions about what's the right way to discover new things and so this book is part of ongoing discussion on what the future nurse i should be but i would say the last thing is that i felt that the quest to find a connect them is an incredible story with a certain mythic power and that story just want to get out of me let's consider a different quest maybe a converted quest which is that of constructing artificial intelligence

setting a kid these days can go to the movies and cds robots that talk and walk like humans and come away with this dream i'm going to create an intelligent computer and kids like that come to me at mit right students in my classes say i've had this dream since i was a kid i want to make a computer that intelligent wanted even more intelligent than i am so this is a kind of mythic west for humanity that's been around for a long time and it continues to capture the imaginations of people the neuroscience is a similar quest which is the quest to do deconstruct our own brains to take them apart figure out what makes them tick and finally to know ourselves and so the book tries to make explicit this notion of a quest that we're all on and how people appreciate that poetic mystery beyond simply taxpayer accounts of this factor that fact about the brain what's the message of the messages that we know

so little about the brain right now but because of the development of many fantastic new technologies including the us refining connect jones nurse science is and train an incredible era of discovery in which we're going to learn a lot and we're going to the dress many of the really important questions that people wonder about not just my new shed not details but the big questions about how we learn and change how mental disorders are based on the structure of the brain and so on were things so much for being here sebastian you have just been listening to sebastian song professor of computational neuroscience and physics at mit an author of the book connect on how the brain's wiring makes us who we are published in two thousand and twelve by houghton mifflin harcourt for more information check on the web at daddy daddy daddy a duck connect on the book dot com again that's connect on the book dot com and another website is high wire dot org that's e y e debbie i are a priority the

sustainability second of mind over matters program you just heard will be on the streaming archives section of k e x keys website ep xv died orgy for the next fourteen days in addition sustainability sigman interviews are available as podcasts go to k e x p dowd orgy click on demand and then podcasting i'm diane warren thanks for listening and be sure to turn into the sustainability segment again next week a ninety point three fm in k x p dido it