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I'm going to try to start promptly at 1105 each time so welcome is everybody psyched I'm psyched uh this is 9 13 the human brain I'm Nancy camwisher I'm the Prof for this class unless you were wondering I have a brain and there it is that's me with some bits colored in that you will learn about in this class okay what I'm going to do today is I'm going to tell you a brief story for around 10 minutes and then I'm going to talk about the why how and what of studying the human brain
0:44
why it's a cool thing to do how you do it and what in particular we're going to learn about in here and then we'll do some mechanics and details of the course and allocation of grades and all that it's on the syllabus anyway cool that's the agenda all right so let's start with that story for this I'm gonna sit up here um the story isn't that long but it has a lot of interesting little weird bits so I have cue cards to remind myself of all the bits I want to remember to say
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um so you can put away your phones and your computers and you don't need to take notes this is just a story it's going to foreshadow a lot of the themes in the course but it's not stuff you're going to be tested on okay so um this is a true story and I've changed only a few tiny little bits to protect the identity of the people involved but otherwise it's an absolutely true story it's a story about a scary medical situation that happened to a friend of mine a few years ago
1:50
but at the same time it's a story about the nature of the human mind about the organization of the human brain and it's also a story about the ability or lack thereof to recover after brain damage it's also incidentally a story about resilience privilege expertise and all of those things that are characteristic of many people in Cambridge Society um not so relevant for the course but all right here goes um so a few years ago a friend of mine was staying over at my house in
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Cambridge on route to a conference in a nearby state and this guy I'll call him Bob was a close friend of mine I'd known him for years and years we had we talked regularly we went on hiking trips together we were pretty close so he's on route to this conference he's staying over at my house the night before um and he the plan was for him to get up early the next morning and drive to the conference so we hung out the night before and chatted and the next morning
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he's sleeping in the Next Room over from mine and early in the morning I hear some shuffling I think yep okay Bob is packing to leave and thank God I don't need to get up I'm only dimly awake and so I'm not paying that much attention Shuffle Shuffle in the background and then I hear a crash
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and I think what the hell is that and I get up and I go into the Next Room and Bob is lying on the floor not moving I say Bob and there's no answer and then I showed Bob and there's no answer and then I dialed 9-1-1 while we were sitting there waiting for the ambulance to arrive Bob starts to wake up and he's very woozy but he's alive and he's making a little bit of sense and he can't figure out what's going on and neither can I and so we're talking and chatting and
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he's making a little more sense but we still don't know what's happening so then the ambulance arrives incredibly fast so like three minutes boom there's three EMTs rushing in the front door rushing up to the room where Bob was and they take all his vitals and they can't find anything wrong and so they're really casual I guess they confront stuff like this all the time I don't Bob doesn't but they're very calm about it and they're saying well can take him to the hospital or not
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and I was like I think we need to know what just happened even though he seems okay we kind of need to know what this is all about don't you think they're like yeah you come to the ER and I said well do we need to waste ambulance resources or do you think it's safe if I drive him myself since there's a hospital not far away I said you can drive him yourself so I drive Bob to the Mount Auburn Hospital ER which is like less than a mile from my house and we do the usual ER thing which is
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mostly waiting and waiting and waiting but various docs come by and they take all these tests and they take all these history questions and it goes on and on and basically they're just not finding anything so after about an hour or two of this they're still doing tests they don't want to quite let them go yet because they don't know what happened everybody's calm about it I figure okay fine I got work to do and I tell Bob um you know text me throughout the day
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and I'll come get you whenever they're ready to release you and so um I go into work but just before I go into work the thought flashes through my mind and I say to the ER doc you know you should check Bob's brain and the reason that thought flashed through my mind is that actually I had been worrying about Bob for a number of years and I hadn't really it hadn't quite registered consciously I hadn't was kind of too horrifying a thought for me to really allow myself to realize I was worried
6:07
about Bob's brain but I was worried about a very particular thing and that is that Bob had been showing these weird signs that he often got lost and didn't know where he was and on the one hand this just didn't make any sense because he was fine in every other way but it was really pretty striking so one time I was over at Bob's house with some other friends of ours and the friend asked Bob how do we get how do I drive from your house into Cambridge and Bob said well you go to the end of
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the driveway and you turn left my friend and I looked at each other like Bob what and Bob thinks about it for a minute yeah into the driveway turn left I just had this like sinking feeling of dread in the pit of my stomach but we sort of made light of it and made fun of it and it went by it was like no you turn right and we gave the directions another time A friend of mine was driving with Bob in Bob's hometown and noticed that like Bob didn't seem to know how to get to the grocery store
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in his hometown where he lived for a really long time and you know a trip he'd made hundreds of times another time I was at a conference in Germany and I saw you know these arrays of posters of people presenting usually pretty dry scientific things and out of the corner of my eye I see the title of a poster and it says navigational deficits colon and early sign of Alzheimer's and I saw that and I just thought and I just kind of suppressed the thought oh my God Bob wasn't that old I know
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Alzheimer's can very rarely strike early I just I didn't want to think about it but it was like rattling around in the back of back of my consciousness so there had been these signs but as I say they didn't make sense because Bob was holding down a very high powered job he was writing beautiful prose he was the life of every party he was at witty funny everybody's like favorite life of the party so how could that be like it just didn't make sense that there would be anything
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wrong with Bob's brain so I managed for a few years to notice these signs and ignore them and not pay any attention um
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so the killer thing is I should have known better my research for the last 20 years has been on the very fact that there are different parts of the brain that do different things and one of the coral areas of that is you can have a problem with one of those parts and the other parts can work just fine and so I if anyone should have realized yes there's something really wrong with Bob's navigation abilities and the fact that he's smart and witty and funny and
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holding down a high-powered job doesn't mean there isn't something wrong with his brain with a part of his brain but I didn't realize that but then you know as I'm leaving the ER it kind of all clicked and I said to the ER doc you better check his brain I thought Bob was out of earshot when I said that he heard it he's like what I was like oh never mind um anyway the ER doc with the kind of confidence that only docs can muster or said nope not a brain thing this is a hard thing
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which wasn't exactly reassuring um but I set aside the brain thought um and I went off to work so throughout the day I texted with Bob a few times things seemed to be fine they'd done more tests they weren't finding anything we just got calmer and calmer about it I guess sometimes weird stuff happens and you just move on but then that night around seven or eight at night I was over at a friend's house and the phone rang and it was Bob I picked it up and Bob says get over here
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they found something in my brain so I ran out of the house grabbed my phone and as I'm driving to the Mount Auburn ER I called my trusty lab tech an amazing guy who keeps track of all kinds of things much better than I do and I said I remember that we scanned Bob a bunch of years ago for a regular experiment in my lab and I don't remember the date I don't remember anything about it but dig around in the files and see if you can figure it out it might be useful to have that scan
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so by the time I get to the ER my lab tech is already texted me back and said found the scans I'm putting them in a Dropbox for you so I go into the ER and there's Bob in the ER Doc and Bob says to me um do you want to see it the ER dock or the radiologist has already shown Bob the picture of his brain and so they take me in there and I look at it and I gulped there was a thing the size of a lime smack in the middle of his brain pretty terrifying so um
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this lime in the middle of Bob's brain was right next to a region that my lab had studied in great detail in fact my lab had discovered that a brain region right next to where that lime was located was specifically involved in navigation how could I not have put all this together but I didn't until that moment and I thought of course of course there's a thing in his brain right next to the para hippocampal Place area which I discovered and a nearby related region
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called retrospolineal cortex of course and how the hell could I not have known but I didn't know um in that earlier work it had been nearly 20 years ago I had a postdoc named Russell Epstein and Russell was a computer vision guy and he wanted to understand how we see by writing code to duplicate the algorithms that he thought go on in the human brain when we understand visual images and that's a very respectable cool line of work which we'll learn a little bit about in here
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and Russell was really a coding guy at the time we were just starting doing brain Imaging but Russell was like poo pooing at all it's like the flash in the pan it's going to go by it's trashy so you guys get nice blobs on the brain I'm not having any of it and I kept saying Russell you need to get a job just do one experiment so you can show in your job talk that you can do brain Imaging it might help you you don't need to do a lot of it just do one dumb experiment
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Russell was interested in how we recognize scenes not just objects and faces and words but how do we know where we are and how do we recognize if the scene as a city or a beach or whatever it is I said okay Russell we'll just scan people looking at pictures of scenes and looking at other kinds of pictures and we'll just kind of see if there's any part of the brain that responds a lot to scenes it really was not well thought out this is not how you should do an experiment it shouldn't be based on
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political calculations lack of theory any of the above but the fact is that's why we did that experiment Russell needed to be able to show a brain image in his job talk so we scan some people looking at scenes and the results knocked our socks off we found a part of the brain that responds very selectively when you look at images of scenes not when you look at faces objects words or pretty much anything else and so we'll learn more about that later in the course we called it the para
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hippocampal Place area and that launched a whole major line of work in my lab and now dozens of other labs around the world so backtrack we'd already found that region and here's this lime in my friend Bob's brain sitting right next to the para hit the gamble Place area
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okay so then I remembered let's look at the scans from my lab from a few years ago in Bob's brain and so I fiddled around and found managed to download the files and there it was you could see that same blob but in the scans from a few years before it was much smaller it was the size of a grape right and so that told us a bunch of things most importantly it told us this thing is growing really slowly and that was hugely important because brain tumors are very bad news and they
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usually grow really fast and the fact that it grew really slowly told us that this was not one of the kind of worst most invasive most horrible ones it was clearly a problem it was big but at least it wasn't growing hugely fast but how poignant that there it was in my own damn data and I hadn't seen it in my friend's brain well I'm not a radiologist I'm a basic researcher and I didn't look and I didn't see it um so indeed the next day the uh the docs told us that they thought this was
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meningioma not cancer who knew that you could have tumors that weren't cancer but you can and they still need to come out if they're big enough and that's very serious but it's not as bad as having a cancer in your brain um so as we're collecting information the next day I'm hanging out in the hospital room and there was an amusing moment when one of the residents came by and he's taking the history and asking all the basic questions and I said kind of sheepishly because you don't want to
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seem like you know more than the residents and in fact I didn't really know more but I just thought I'd provide a little information I said you know he's actually had symptoms for a bunch of years and there's a there's a region of the brain nearby that you know that I've actually studied a little bit and the residence is like we know who you are [Laughter] um so much for my you know trying to stay under the radar um I that afternoon I talked to a neurosurgeon friend of mine because I
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figured okay we need we need advice we need help and the um the neurosurgeon friend said um quote it like got branded in my brain she said it is a Paramount importance that you find the best neurosurgeon it's the difference between whether Bob dies on the table or goes on to live a normal life so this is the privileged part of the story I'm not that well connected but I'm a little bit connected and I kind of dug around and did what I could and we spent a couple of weeks and we found
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the best neurosurgeon and the night before the surgery Bob is staying over at my house because the surgery was in a Boston hospital and I thought you know I've been dancing around this for years but now like it's all out in the open we know there's a problem and I'm going to test him I'm going to find out what the hell's going on this is after all one of the basic forms of data that we collect in my field that is testing people with problems in their brain to try to figure out what things
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they can do and what things they can't do it's a way of figuring out what the basic components of the mind and brain are it's actually the oldest most venerable method in our field and it's still a hugely important one so I thought what the hell so I said okay Bob draw me a sketch map of the floor plan of your house and so Bob takes a few minutes and he draws this thing and it was shy there weren't even you know the the rooms in a kind of rectilinearly arranged house they weren't even aligned
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there was like a soup of wine so there was no organization from one room to the next and Bob kind of realized this kind of isn't right is it but he didn't know how to fix it and he said he just couldn't visualize what it looked like to be in his house and so we couldn't draw the floor plan and I thought okay he hasn't been there in a couple of days I gave him another piece of paper and I said okay draw the floor plan of my house where you are right now um and so Bob took a couple minutes and
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delivered a similar mess he couldn't even imagine the layout of the room next to him that he'd been at been in a few minutes before and then trying to channel my inner neuropsychologist I thought okay gave him another piece of paper and I said okay Bob try a draw a bicycle why did I choose a bicycle because it's a multi-part object that has a bunch of different bits that have a particular relationship to each other just as the rooms in a house have a particular
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spatial relationship to each other and I wanted to know is his problem specifically about places or is it out about any complex multi-part thing that you have to remember the relationships to Bob is no artist to put it mildly but his bicycle was clearly recognizable as a bicycle it had the two wheels in the right relationship and you know it had all the basic parts in roughly the same the right place I then had him draw a lobster another multi-part object and also his Lobster
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was not beautiful but had everything in the right place and so that's very telling he had a specific problem in I don't know imagining reproducing remembering it's not totally clear the arrangements of parts in a room but not the arrangements of parts and an object okay and we'll get back to that more in a few weeks um okay so um what do I want to say here I said all that so the next day Bob has an 11 hour surgery major hardcore extreme neurosurgery remove a huge piece of bone
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from the back of your head pull apart the hemispheres of the brain like this go in like multiple inches and remove a lime like holy crap right said lime was right near the vein of Galen right Galen lived what a couple thousand years ago the fact that there's a vein of Galen means it's a big ass vein the kind of vein that even Galen would have found with you know dissection 2000 years ago this lime was all wrapped around and interleaved with the vein of Galen not
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good but because we found the best neurosurgeon and because we have extreme privilege and all the all the possible medical resources and expertise you could possibly hope for Bob sailed through the surgery and an hour after the surgery I'm chatting with him and he's making sense amazing right so um and you know two literally two days later they sent him home and a few days after that he's back at work no problem totally fine but now we get to the question you're probably thinking about
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what about his navigational abilities the sad answer is nothing doing none of it came back at all thank God for iPhones if Bob lived 30 years ago he wouldn't be able to function but he goes everywhere using his iPhone GPS everywhere um and this fact that he didn't recover his navigational abilities is consistent with the whole literature that we'll consider later in the course that often not always but often if you have brain damage especially to some of these very specialized circuits that
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we'll talk about you don't recover later if the damage is early you may well recover early in life you may well recover children have much more plastic brains that can adjust after brain damage adults not so good
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um so Bob's doing fine that's my story any thoughts or questions yeah yes
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and it's very interesting there are many of his spatial abilities that are absolutely intact and yet the ones related to navigation are not yeah yeah no problem but he's always looking at his damn phone to get directions or to listen to you know the the GPS directions system so driving is no problem it's another kind of left right the immediate spatial orientation abilities are absolutely fine but knowing where am I now and how would I get there from here is blitzed other questions yeah
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great question yes he can recognize familiar places what he can't do is he can say oh right that's the front of our house or that's a cafe you know that's such and such Cafe that's near our house what he can't do is say which way would you turn from there to go home
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like multiple scenes great question great question a little bit so he can navigate a little bit with his GPS and because he's learned certain routes as a series of almost verbal commands like if you're here turn right then like that whole kind of thing it's not what any of you guys could do if you guys are driving around in Cambridge or walking around campus remember when they blocked off this whole middle of Campus a couple years ago it was so irritating I would like go there it's like oh God
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they've blocked it off I can't get over to you know Lobby seven well you immediately come up with an alternate route it's like okay I guess we're going to have to do this you come up with an alternate route this is what you're never a normal navigation system can do Bob can't do that at all he's like root block no idea get out the phone right yeah so you get it like estimating distances like does he know like something is like a certain number of miles away yes
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yes he is and that's very interesting but that seems to be kind of a different thing you could think about all the different kinds of cues you have for distance beyond your ab your kind of literal navigation skills
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uh a little bit a couple minutes yes the next day you know I mean it would it would be kind of like this thing it's like you know I sort of vaguely remember that I was here I turned right so I better do that again
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no not very well and this is a problem because iPhones don't usually yeah so new hotels big problem finding the bathroom down the hall or the front door in a hotel big problem yeah I mean you know these are problems you can you can come up with workarounds but it's not life-threatening but it's extremely inconvenient yeah so this is the case navigational skills that developed like longer a long time ago those are stronger so like he has a harder time developing like it's very time you say
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new hotels are a problem but different suffix is like more familiar like his home it's it's easier it's a great question and you might think that the the kind of navigational Maps you laid down long ago would be intact so is it just that you can't learn new ones um so it's a it's a great question the answer is kind of complicated in this case for roots that he's memorized there's a whole different system for knowing a route and really having an abstract knowledge of a place that
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enables you to devise a new route if something is blocked on that route right so for highly overlearned Roots he's okay like he remembers like the zidu it's like a sequence it's like a it's like a memorized motor sequence you do a and then B and then C and then D so he's okay with those with roots he learned long ago but he is not good at coming up with a new root in a place that he learned long ago all right we'll take one last question is
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um and then we have conscious knowledge that this is
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no he knows well he knows because like when he tries to figure out which way to head he has no idea so he's extremely aware of it and very articulate on precisely what happens and so what he says is like if he's looking at if he's looking at a place here's something he says he's looking at a place he knows where he is because there's all kinds of other bits of information that tell you where you are because you intended to go there and the relevant things are
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happening and all this who knows where he is and it looks familiar if he tries to imagine what's behind him he says that he like starts to get it and it just kind of vaporizes he just can't hang on to it he can't kind of construct a stable mental image of nearby places so I don't know exactly what that means but he's very articulate and can report what happens what he experiences when he tries to access this kind of information so what you guys will go on but what I
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want to say is what you guys just did is exactly what we do in my field we try to take a mental ability and tease it apart and say is it exactly this or is it exactly that and you guys all just did it beautifully right so a lot of what we do in my field is kind of this kind of Common Sense parsing of mental abilities what is a particular mental ability you know how does it relate to some other one are these things separable can you lose one and not the other do they live in different parts of
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the brain Etc all right so that's the story I'm going to cash out some of the um uh particular themes that that came out from the story that will echo through this course and the first and most obvious one is the brain isn't just a big bunch of mush right it has structure it has organization the different bits do different things okay importantly when Bob had this big lime in his head he didn't just get a little bit stupid no his IQ if he'd take an IQ test would
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be unchanged he lost a very specific mental ability okay and that is fascinating um but it's also good news for science because often when you try to understand a complicated thing a great way to make progress is to First figure out what the parts are and then later try to figure out how does each individual part work and how do they work together but if there's part structure there's at least a place to start okay second theme is that some parts of the brain do extremely specific things right
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not all of them some of them are quite General and are engaged in lots of different mental processes but some are remarkably specific we'll talk a lot about that third big theme the organization of the brain Echoes the architecture of the Mind um and I would say the fundamental pieces of the brain are telling us what are fundamental parts of the mind and that's why I'm in this field that's what I think is cool you know the brain is just like a bunch of cells like it's a
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physical thing who cares about a physical thing the reason we care about it is that's where our mind lives and if we study that physical thing we can learn something about our minds and that's pretty Cosmic I think so the point of all of this kind of work is not to say oh that mental process is here not there who cares I don't really care I mean at some point you need to have a ballpark sense you need to know to study the things but the interesting question is not where these things are
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in the brain but which mental processes have their own specialized machinery and why those yeah another important theme how do brains change right Bob didn't recover after his brain damage in that very particular mental function that he lost if it if all of that had happened when he was five five years old he probably would have right so how do brains change over normal development how do they change from learning and experience how do they change after injury
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and the final theme echoed uh in that story is there are lots and lots of different ways to study the brain right they're the simple behavioral observations Bob can't navigate but he can do everything else okay that's really deep and informative low-tech but really powerful right um the anatomical brain images that showed where the line was in Bob's brain right that gives you another kind of information what's the physical structure of the brain the functional images that we had done
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in my lab to discover the para hippocampal Place area and the studies of what mental abilities are preserved and which are lost in people who have alterations of their brain okay so those are just a few of the kinds of methods in our field Each of which tells us about a different kind of thing about the brain okay so those are the themes I was trying to get at here so let's move on to um the why how and what of exploring the brain I'm going to sign the Tas to get me to shut up at
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um let's see we're supposed to end it five minutes before the end of class is that right is that MIT tradition okay so at uh oh my shockingly soon um 11 45 um you're gonna um no oh great thank you thank you this is one of the many things Tas are for they pick up the hundreds of typos and mindos and all of that excellent I'm thinking how the hell did I so miss time this thank you heather okay good we'll go on okay why should we study the brain first most obvious reason know thyself
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know what this thing is that's operating in our heads this is who you are right is your brain there are lots of very fine and important organs in the body um but the brain is special right so you know a heart is important you die without it but it's the brain that's your identity right so there's a reason that surgeons do heart transplants that makes sense something wrong with your heart you need another heart okay but why don't they do brain transplants that would make sense right if there's
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something wrong with my brain it doesn't make sense to take someone else's brain and put it in here because then I'd be that other person it doesn't make sense because the brain is who you are okay so the brain is really special it's not just another organ that's why a few years ago we had the decade of the brain right not the decade of the pancreas or the liver or the kidney right people need to study these things they know how to fix the they need to know how to fix
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them they're important but they're not as Cosmic as the brain okay all right um second reason why we should understand brains and that is to understand the limits of human knowledge like the more we understand about the human mind the more we can like actually evaluate how good our knowledge is are there things that we might not be able to think possible true scientific theories we might not be able to understand ever you can think of studying the Mind as a
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kind of empirical epistemology a way to actually know about the knower so we can figure out how good the knowledge is in that knower right so that's another reason a third reason is to advance AI and so up until a few years ago I used to give lectures on vision and they would all start with some version of this you guys all have amazing visual abilities in the back third of your brain that does vision you can do all this incredible stuff that no machine can touch
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hats off to you you have an amazing visual system back here and those guys in AI that is mostly guys guys gals whatever those people in AI could only dream of coming up with algorithms as good as the one that's running in the back of your head you can't quite start the lectures that way anymore so if any of you have been living in a cave and not heard about deep Nets there's been a massive Revolution and all of a sudden deep Nets are doing things that are really close to human
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abilities particularly in vision so for example in visual object recognition machines were way far behind human Vision until very recently especially when this paper here came out was published in 2012 first author krishevsky it has now been cited an astonishing 33 000 times actually I made this slide a couple weeks ago it's probably been cited 36 000 Times by now you can look it up on Google Scholar and find out that is a huge number of citations the influence of this paper is ginormous
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probably half of you have already heard about this paper raise your hand if you've heard about this paper oh okay all right right major big news okay so what's so important about this paper uh well they they trained as probably most of you know they trained a deep net on the over a million images in imagenet a massive computer database of images and they basically taught it to do object recognition and it performs much more accurately than any previous system and it
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approaches human abilities okay so this is Major is a radical change in the situation that we were in five years ago so things have changed radically so just as an example here's some of the um one of the figures from that seminal paper so here is one of the images from imagenet that um that alexnet this trained network was tested on and the correct answer according to imagenet is that that's a might and here's what alexnet says it's number one first answer is might in its second third
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fourth answer is our Black Widow cockroach Etc right so pretty damn good the might is even sticking off the edge of the frame and it gets it container ship First Choice container ship pretty good second choice makes sense Lifeboat not bad look at that motor scooter I can barely even see the motor scooter in there but alexnet awesome right leopard awesome okay even when Alex net makes a mistake the mistake is totally understandable like according to imagenet that is a
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picture of a grill and Alex net calls it a convertible I'm siding with Alex net on this one over image this the correct answer is mushroom and Alex net says agaric I had to look that up it's like a particular kind of mushroom um this one's pretty funny um imagenet says that's pictures of cherry there's cherries in the foreground but Alex net says Dalmatian I'm siding with Alex net on this um and you know Madagascar cat Etc so pretty amazing and like nothing even
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close to this was possible before 2012. so this is very recent history and it has totally shaken up the field in lots of ways um and so that's been transformative not just for computer science but it's also been transformative for cognitive science and Neuroscience because now we have algorithms like here's this deep net and it does this thing so that's a possible theory of how humans do it it's a possible computationally precise theory of what's going on in here and we
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didn't used to have those and now we have those for a number of domains and that's shaking up the field there will be a whole lecture on deep Nets and how you can use them to think about minds and brains toward the end of the course guest lecture by my postdoc Katherine Dobbs and we'll hear more about that um but let's first step back a second and say okay do they really perform as well as humans even on just object recognition
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on images not in imagenet like imagenes pretty good tests because these things as you can see are highly variable they have backgrounds they're complicated they're real world images but you know they were photographs taken by people in a particular way what they you know with a particular goal um and most of the photographs you take you throughout they don't end up in imagenet right imagenet is a weird little idiosyncratic subset of the kind of visual experience that we have so
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would this really generalize so it so happens that um Boris Katz and Andre barbu across the street in seasail have been doing some very interesting studies this stuff isn't published yet but I got their permission to tell you about this cool stuff they're doing and they're saying hey let's test alexnet and other similar deep Nets since then uh on a more realistic harder version of object recognition that's more characteristic of what humans do and so they're generating this huge data set of
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stimuli that they crowdsource and so people workers on Mechanical Turk go on there and create images for them and so they get instructions like you know hold a hold a object in this particular location or at this angle or move it here and like send us the images so they are getting I think hundreds of thousands of images to test this on and they're much more variable in the location of the object in the image and its orientation and so forth so for example you guys have no problem telling
40:06
what that thing is but it's a slightly atypical example likewise what's the object on the floor there you can tell what it is but it's it's slightly a typical example and so um what Boris and Andre are finding finding is that human performance is still pretty good on these images but the Deep Nets are terrible at this stuff okay so resnet one of the more recent ones drops from 71 correct on imagenet to around 25 correct on these images and the other um similar fancy more recent networks do
40:42
similarly badly so on the one hand uh AI the Deep Nets are awesome and transformative no question about it but on the other hand despite all the hype they're still not quite like human object recognition right they're a whole lot closer than they used to be but they're not really there okay and more generally what about harder problems like image understanding not just labeling and classification but understanding what's going on in an image okay so you guys have probably
41:14
seen image captioning Bots there are lots of these around now this kind of Hit the scene in 2016. when Google AI came out with a captioning algorithm and of course right around the same time Microsoft had a captioning algorithm and let's see how they do so this is an example you give this algorithm this picture here and it says um that's a dinosaur on top of a surfboard that's pretty damn good right like okay wow let's look more generally how well this thing works at other examples okay it
41:48
looks at this and it says that's a group of people on a field playing football it's like wow okay a snow-covered field pretty good view she win and uh ding ning posing for a picture I don't know but these things are very good at face recognition that's probably exactly those two people right a car parked in a parking or car yeah car parked in a parking lot pretty good a large ship in the water pretty good a clock tower lit up at night awesome right a vintage photo of a pond
42:25
well the Vintage part I don't know where the pond is there's a little water in there I don't know not way off a group of people that are standing in the grass near a bridge not really there's grass there's a bridge sort of there's people but not really right a group of people standing on top of a boat definitely not a building with a cake what a person holding a cell phone not a group of stuffed animals I love this one a necklace made of bananas wow we've really landed on Mars here
43:16
sitting on the grass talk about missing the boat now look at this picture for a second just figure out what's going on here
43:29
takes a couple seconds everyone got it there's a lot going on here okay so this algorithm says I think it's a group of people standing next to a man in a suit and tie and the algorithm is correct but the algorithm has profoundly missed the boat okay so I'm channeling actually I stole these slides from Josh Tenenbaum but let me channel him for a moment and say what his big idea is which I think is really important and that is that both humans and deep Nets are very good at pattern
44:00
recognition pattern classification this is a cat or a dog or a car or a toaster right what they're not good at what humans are good at but the Deep Nets are not is building models to understand the world and so when you look at this picture there are all kinds of things that are crucial for really understanding at a deep level what's going on in here we need to know why some people what some people here know but the guy on the scale does not know namely even if you don't recognize that
44:30
that James that that's James Comey I think it is here's Obama with his foot on the scale you need to know that people find it embarrassing if they weigh too much you need to know that he can't see that Obama's doing it you need to know that they can see it even though he can't and that's kind of the essence of humor there's just a whole universe of Rich structural information going in here that is part of what it means to understand this picture and no deep net is even close
45:00
to doing that kind of thing okay so bottom line of all this is or let me just go on more generally AI systems can't navigate new situations infer what others believe use language to communicate write poetry and music to express how they feel or create math to build Bridges devices and life-saving medicines that's a quote from our leader Jim DiCarlo head of this department published and wired a year ago in a beautiful article on the limitations of deep Nets um but more generally the point is that
45:40
yes AI is taking a massive leap now when we're right in the middle of it and it's super exciting and it's helpful to neuroscience and cognitive science um but AI has a lot to learn from us too right a lot to learn from what's going on in here and how this thing works that those AI systems still can't touch okay so all of that was my third reason for studying we're still in the Y are we studying the human brain the fourth reason to study the human brain is the one most compelling to me
46:07
and that is that it is just simply the greatest intellectual quest of all time we could fight about cosmology I'm not going to fight with you about anything else I don't think there's any contest it's the greatest intellectual quest of all time and that's why I'm in it and that's why I hope it'll be fun for you okay that was the why um how are we going to study the human brain so here's this thing how are we going to figure out how it works it's kind of daunting it's not totally obvious
46:37
the first thing to realize is that there are lots of levels of organization in this thing and hence lots of ways of studying it we could look at molecules and their interactions lots of people in this building do that we could look at properties of individual neurons we could look at circuits of neurons interacting with each other we look at entire brain regions and what their functions are we could look at networks of multiple brain regions interacting with each other
47:05
and so all of those things are possible but actually what we're going to do in the course is none of those things in particular instead we're going to ask a somewhat different question and that question is how does the brain give rise to the mind okay and to understand that question we're going to do more at this level and less at the upper levels okay um so to answer this question we need to start with the mind we need to if we're going to understand how does this thing
47:33
produce a mind we need to First figure out what is a mind what do we know about minds okay um and so we need to start with the various mental functions that Minds carry out things like perception Vision hearing aspects of cognition like understanding language thinking about people thinking about things Etc okay and so for each mental function what we're going to do in here is start by trying to understand how it works in Minds as well as we can or like what it is that we're trying to
48:05
understand that Minds can do what is computed and how and then we're going to look at its brain basis and try to figure out what we can figure out about how that mental function is implemented in a brain so the first question we'll ask for all of these domains is is there specialized Machinery to do that thing and then we'll ask what information is represented in the relevant parts of the brain and when is that information represented okay and how okay so how are we going to answer those
48:34
questions well there's lots and lots of methods in our field okay and so the first set of methods if we want to understand mines the first set of methods are the basic stuff of cognitive science psychophysics that means showing people visual stimuli or playing them sounds and asking them what they see or hear nice and low Tech but lots has been learned from those methods you collect reaction time and accuracy and it's amazing how much you can learn from these methods that have been around for
49:01
100 years or more perceptual Illusions are similarly very informative about how minds work now let me say an important thing that arises here last year was the first time I taught this course and I would say it went so-so I'm aiming for it to be much better this year and one of the ways I'm trying to do that is to be responsive to the student of owls I got last year which were not fabulous across the board hurt my feelings badly but once I got over myself I decided to just listen to
49:30
them and try to fix it and one way to fix it is to be honest with you today about what this course is going to cover so in my avails student 50458 bless them offer this comment this class was not sold in the correct way it should not be called the human brain because it was basically just a cognitive science not a brain class I expected to learn very different material so I don't know who the student is I wish I could apologize to them but I will say to you uh sorry student 50458
50:00
sorry I didn't make that clear the fundamental reason the brain is cool is that it gives rise to the mind and that means that studying you know the biological properties of the brain without considering the mental functions it implements it would be kind of like trying to study the physical properties of a book without considering the meaning of its text so we're going to spend a lot of time doing cognitive science in here and if you had a different impression uh sorry
50:26
about that but that's what we're doing here okay all right so how are we going to answer it so lots of cognitive science um so how are we going to look at the brain basis well we're going to look at neuropsychology patients people like Bob who have damage to the brain and what functions get preserved and lost we'll use we'll look at a lot of studies with functional MRI neurophysiology where you can record from Individual neurons in animal brains and in rare occasion cases
50:53
even in human brains under clinical situations where they need to have electrodes in their brain anyway for neurosurgery we'll look at EEG recorded from electrodes on the scalp um and Meg recording from magnetic fields from squids placed next to the scalp we'll look at connectivity measures with a method called diffusion tractography Etc so lots of methods and so which mental functions will we cover well to tell you about that I need to tell you about the huge progress that
51:25
has happened in our field in the last 20 years okay all of this is quite recent and so let's back up to 1990 here is approximately what we knew about the organization of the human brain in 1990. the black ovals are the bits that are primary sensory and motor regions that have been known for a long time even by 1990. and the colored bits are the bits where we had some idea that face recognition might go on somewhere in the back end of the bottom of the right hemisphere
51:55
because of people who had damage back there and lost their face recognition ability sometimes preserving their ability to visually recognize words and faces words and scenes and objects only losing their ability to recognize faces okay the language regions we had known about for nearly 200 years from broca and Wernicke and others who had studied patients with damage in those regions and noted that they had problems with language function and similarly many people had reported
52:22
that if you have damage up here in the parietal lobes you sometimes lose your ability to direct your attention to different places in the visual scene so that was approximately what was known in 1990 and here's what we know now we now know thanks largely to functional MRI um that for dozens of regions in the brain in every one of you we have a pretty good idea of the function of that region this is Major progress right this is a kind of rough sketch of the organization
52:57
of the human mind and brain that we have now that we didn't have 20 years ago and that's awesome um and so that is made possible a lot of progress building with other methods and so what we'll study in this course is we'll focus on those mental functions where the brain bases are best understood okay and that will include things like the visual perception of color shape and motion visual recognition of faces places bodies and words and scenes didn't make it on the slide
53:29
oh yes it did perceiving scenes and navigating understanding numbers yes there's a whole lot about the brain basis of understanding numbers perceiving speech and perceiving music understanding language understanding other people and their minds okay so those are the kinds of topics where there's been a lot of progress recently in understanding the brain basis of those mental functions and so those are the ones we'll focus on and that means there's going to be a lot
53:59
on perception high level vision and high level audition um because you know that's one where a lot of progress has been made and it's also a lot of the cortex right as I mentioned a moment ago the whole back third of your brain does vision construed broadly right and so some people might say why are she spending all this time in Vision well it's like a big part of what your brain does we are very visual animals so we'll spend a lot of time on vision um okay and so for each of these
54:24
functions we will ask to what extent is this mental function implemented in its own specialized brain machinery are there multiple different brain regions that carry out that function what does each one do is there a division of labor between those different regions how does that system arise in development how does it does it have homologs in other species are these things uniquely human or which of them are and also along the way other side cool questions that will come up
54:59
what if anything is special about the human brain how come we are taking over and largely destroying the planet and other species are not right besides destroying the planet we're doing some other cool things like inventing science and engineering and medicine and architecture and poetry and literature and all these other and music all these other awesome things that other species aren't doing how come our brains are doing that and other species aren't where does knowledge come from
55:28
you guys know all this stuff how much of that stuff was wired in at Birth and how much of it did you get from experience um how much can our minds and brains change over time can we go study a new thing and get a whole new brain region for that thing um can we change the basic structure just by training or after brain damage can we think without language right how many of you have wondered about that question yeah really basic question Anya's answering it Anya and some others
56:04
but Anya's doing a lot to answer that question they're actually empirical answers to these long-standing deep questions that everyone wonders about that's pretty cool um somebody back there asked a while ago about awareness can we think perceive understand without awareness how much can go on like in the basement of the brain when we don't even know what's going on down there we'll consider all of these other cool questions okay there's a bunch of things we won't cover in this course
56:32
um for various reasons that could have been in here and just aren't there's only so much time motor control it's really important to know how you do things like pick up objects and plan actions and um we're just not covering that something had to go um subcortical function all this is a very corticocentric course most of the course will deal with the cortex that's where most of conscious thinking and reasoning and cognition happens there's a lot of good stuff down in the basement
57:00
of the brain and it's going to get pretty short shrift okay not for any good reason what it is decision making important field not getting much coverage in here importantly circuit level mechanisms explanations of cognition like if you think that we're going to understand not only what it means to understand the meaning of a sentence but that I'm going to give you a wiring diagram of the neurons that Implement that function sorry to be the bearer of bad news but
57:26
nobody has a freaking clue how you could get a bunch of neurons to understand the meaning of a sentence okay so that's exciting that means there's a field for you guys to waltz into and probably in your lifetimes people will start to crack these things right but you know just to know what we're headed into rarely for almost no high level mental functions do we have anything like a wiring diagram level understanding of any perceptual or cognitive function okay so that's not in the cards for this
57:55
course because it doesn't exist in the field um okay for that kind of thing there are cases where you can make progress you can understand say fear conditioning in a mouse like those circuits are being like cracked wide open by people in this building people all around the world with spectacular Precision they know the specific classes of neurons their connectivity they know every damn thing about them but it's like you know how does a mouse learn that this thing is to
58:21
be afraid of this thing okay that's important you know for more complex aspects of cognition in humans we can't usually have that kind of circuit level understanding lots of other things that will get short shrift memory not for any good reason I mean there's a lot of coverage of memory in 900 and 901 and it's just somehow off a blind spot for understanding I've heard knowing how to talk interestingly about memory so I'm not going to give you a boring lecture on memory instead I'm not going
58:47
to give you any lecture on memory until I learn how to talk about it interestingly reinforcement learning and reward systems I'm going to try to pull some of that in but it's not going to be a major Focus even though it's a really important part of cognition attention there might be some at the end okay um okay how many of you have taken 900. okay looks like a little over a half okay how many have taken 901. yeah a little over half okay good so um uh if you okay so if you have great
59:23
good for you this course is designed for as a tier two course for people who have taken 900 or 901 if you haven't you're probably okay but you might need to do a little extra work and so I've already posted online uh and in the syllabus information about actually a lecture I gave a year ago on some of the background stuff that is no longer taught in this course people hated it when I taught them stuff they'd already encountered before so I'm trying to minimize that uh and so that's a
59:50
backup for those of you who haven't taken these courses if you're worried about this chat with me afterwards I think it will be okay just count on doing a little bit of extra work not much um okay for those of us you have who have taken it um there's going to be a little bit of overlap it's simply impossible to have zero overlap I mean what does John gabrielli and 900 and Mark bear and 901 do they survey the whole broad field and they pick the coolest stuff out of every
1:00:16
little bit and they teach it to you exactly as they should but that means that when I come along and try to say I'm going to do a more intensive coverage of the coolest things there's going to be a teeny bit of overlap but I'll try to not make it too much okay just because the coolest stuff is the coolest stuff right uh okay um yeah also the spin and the goals of this course are quite different from both 900 and 901 you will have to memorize a few things but not much my real goal in this course
1:00:47
is to have you understand things not memorize a sea of disjointed facts okay so a little more on the goals really what I want you to get out of this course is to appreciate the big questions in the field and what is at stake theoretically in each okay um I want you to understand the methods in human cognitive Neuroscience what each one can tell you what it can't how different combinations of methods can work synergistically and complementally to answer different facets of a question um
1:01:17
I do want you to gain some actual knowledge about some of the domains of cognition where we've learned a bunch both at the cognitive level and the Brain level things like face recognition navigation language understanding music stuff like that and crucially I want you guys to be able to read current papers in the field so if you look in the syllabus the first few papers are like 20 years old but it's going to accelerate quickly and you'll be reading papers I'm trying to
1:01:44
choose mostly papers published in the last year or two okay I'm trying to take you straight to The Cutting Edge of the field okay yeah part of the people is that people straight out of research Labs or are they going to be like their annual meeting nope straight out of research Labs you're going to read the real deal not someone else's uh blurry just they just read the abstracts and put in some stuff in the review article no you're going to read the actual paper that's the whole deal yep
1:02:10
um okay so those are the goals good a few things why no textbook this field is moving too fast for a textbook plus I have strong opinions and I don't like any of the textbooks um so any textbook is out of date we're going to be reading hot stuff that's hot off the press and so there's no that's not in the textbooks yet and so we're skipping that and you're going to go straight to original research article so we'll be occasional review articles where relevant but mostly part of the
1:02:39
agenda of this course is to teach you to be not afraid of and able to read current articles in the field all right you've all been waiting for this okay details on the grading pretty standard midterm 25 of the class of the grade final 25 it will be cumulative but weighted toward the second half um there's going to be a lot of reading and writing assignments approximately uh two papers to read per week um and for usually one of those papers per week you will have a very short uh
1:03:12
written assignment in which usually I ask a few simple questions and maybe one like paragraph level think question um the essence of these tasks is not the written resignment itself the essence of the task is to understand the paper if you've understood the paper as you read it then you should be able to answer those questions pretty straightforwardly um and let me just say that understanding a scientific paper is not trivial when I read a scientific paper
1:03:40
right in my area where I have all of the background it takes me hours hours it may be five pages it still takes me hours it's just how it is so when I assign a paper and you say this oh it's only three pages you know I can I could do that in 20 minutes oh no you can't no you can't right and that's part of what I want you learn to learn how to do is how to like really read and understand a scientific paper allocate the time it takes to really get it okay so that's a
1:04:08
big part of the agenda in this task okay all the stuff um the assignments and the submission of the assignments will all happen on Stellar your first written response to a paper is due February 12th at 6 pm on Stellar but there are other readings that are assigned before that a note about the schedule I struggled a lot trying to both have the assignments happen when you had already learned enough in lectures to know how to do it but have it close enough to the topic at
1:04:35
hand so it didn't seem like no longer relevant that's hard to do both of those things so the compromise is all of the assignments are due at 6 PM the night before the class in which they're assigned and so if you see that it's assigned you know on the 13th if it's listed on the lecture for the 13th check carefully it's probably due the night of the I'm getting this wrong the 12th the night before and that's so that we and the Tas can look at it figure out what
1:05:02
you understood what you didn't and how to incorporate and explain whatever you didn't get in the next lecture okay all right um quizzes I haven't done this before new thing I'm going to try uh they're going to be about eight of these they're going to be very brief they're going to happen at the end of class in class and you will do them on your computer or your iPhone using Google forms if anybody doesn't have a computer or an iPhone they can bring to class the days
1:05:26
of those quizzes let us know after class and we'll come up with a solution okay and the idea of these is not to fish out an obscure fact that was in one of the reading assignments and you know ding you on it like I'm not interested in that the the goal of this is just to keep you up to date keep you doing the readings keep you up with the material and if you basically are understanding what you're reading and understanding the lecture material maybe you glance at
1:05:52
it briefly before you should do fine on the quizzes they're just kind of reality checks right for us to know what people are getting and not okay uh okay first quiz is February 20th uh blah blah there is one longer written assignment that is not due with the usual schedule of all the other things it's due near the end and in that one you will actually design an experiment in a particular area and that will be I don't know yet three to five pages something like that we'll give you more
1:06:19
details on exactly how you want to organize this and it will be very specific like State your exact hypothesis State your exact experimental design Etc and you'll get practice with those things in advance all right so those are the grading and requirements um and this is the um you have this all in the syllabus in front of you this is the lineup of topics but very briefly let me try to give you the Arc of the class um so this is the introduction next time we're going to do just a teeny bit of
1:06:48
neuroanatomy there will be a teeny bit of overlap with 900 and 901 there I'm going to whip through it in very superficial form I'm doing that largely because on the following class we have an amazing privilege which is at one of the greatest neuroscientists alive today and Graybill will be doing an actual brain dissection right here in this class right in front of you it's going to be awesome I can't wait it's an incredible privilege it will be a real human brain and you guys will be and
1:07:15
will be here with all her apparatus and you guys will be clustered around and if it's this many God help us but we'll figure out how to make it work I may let me just say if there are listeners in here I may have to tell listeners they can't come because very sensitive about not having too many people so stay tuned on that I haven't quite decided yet depends how many people are taking um but it's going to be amazing and I want to remind you of just some Basics so you're not asking her like
1:07:38
what is the hippocampus okay so I know you I know you should all know that but we'll just do bear basics um okay and then we'll have the dissection that will be great and also another thing to say is I mentioned that the subcortical regions are going to get short shrift in this class that's true um but a lot of what you see in a dissection is a subcortical stuff right cortex is great but it kind of all looks the same you kind of can't say oh that's the this region that's the other
1:08:03
Regional you can but it doesn't look any different from any other region so um so that's where the subcortical stuff will happen okay okay uh so then I'm going to do a couple of lectures that focus on High level vision perceiving motion and color and shape and faces and scenes and bodies and stuff like that and we will use those both to teach you that content and also to teach you the you know vast array of methods in this field okay we will then have a lecture on the kind
1:08:36
of debates about the organization of visual cortex in humans I have a particular view I'm I'm very fond of views that some patches of Cortex are very very functionally specific not everyone believes that so I have assigned readings of people who have different views we will consider that I will try to expose you to the alternate views and tell you why I'm teaching why I still believe mine but why other smart people believe different things right okay we will then move up the system
1:09:04
from perception and we will spend two meetings talking about scene perception and navigation you've got a hint about what an interesting area this is from the story of Bob we'll consider more what we've learned from studies of patients with brain damage from functional MRI from physiology and animals from cognitive science from the whole glorious menagerie of methods to understand navigation it's a it's a really fascinating area the in the two lectures after that we'll
1:09:31
consider development how do you wire up a brain how much is present at birth what is specified in the genes what is learned and a lot of that will focus on the navigation system and the face system simply because that's where there's a lot known right we'll consider some other things but those are two areas where there's super exciting work from just the last three or four years and so that's what we'll focus on there I'm then going to do a lecture on brains
1:09:58
in blind people how are they different how are they the same what does that tell us and then you have the midterm then we're going to move on and consider number how do you like instantly know that that's three fingers and that's two without having to do anything all that complicated and if I had 25 fingers and held them up you would immediately get a sense that it was about 25 you might not know if it was 22 or 28 but you would know it was about 25 and there are
1:10:27
particular brain regions that compute that for you and we will consider all of that and there's a very rich array of information from studies of infant cognition from animal behavior from brain Imaging from brain damage from single unit physiology and from computation all of which inform our understanding of number those are my favorite lectures so we can take one domain of cognition and inform it with like all of the methods and numbers are really great example
1:10:52
uh then we'll talk a little bit about uh well one of my Tas said call it neuro economics it will sound good but actually what I'm going to try to do is sort of neuroeconomics but it will be about um uh uh Pleasure and Pain and reward and how we think about those things okay um and then that's down to April 3rd just as a side note all of these things are things that are pretty similar between humans and at least primates and some of them are shared with rodents okay
1:11:20
and most of the things after that are things that are really uniquely human okay so we'll be really moving away with less available animal literature to inform the stuff we're looking at because animals can't do these things and so necessarily far from the details of individual neurons in circuits but there's still Lots cool that can be said about how you understand speech how you appreciate music there will be a guest lecture just for fun on brain machine interface by
1:11:48
Michael Cohen who's working in my lab now and who has a great lecture on this topic and then we'll spend a couple lectures on language how you understand and produce language and what the relevant brain regions are what we know about it from cognition and lots of other methods and what the relationship is between language and thought then we'll think about how we think about other people this is called theory of Mind how I can look out at this lecture and try to evaluate from your
1:12:17
facial expression are they bored sleepy overworked fascinated excited all of this kind of stuff that all of us do moment to moment in any conversation and that you know yes lectures are doing all the time even if I know that you guys have too much work and that's why you're sleepy and I shouldn't take it personally um I'm still noticing anyway then we'll go on and consider brain networks right so of course brain function doesn't happen in just a single region even if we spend a lot of time
1:12:46
studying individual regions there's considerable work trying to figure out which sets of regions work together and how could we discover that and what are those broader networks of brain regions and then on May 6 you will have turned in your longer written assignment designing your own experiment and then it makes on May 6 we will work together in groups to refine those experiments and really hash out the details so you actually know how to design an experiment
1:13:12
um and then we will have this guest lecture from my postdoc katharina Dobbs on deep Nets and what they can tell us about cognition and brains and then we'll talk about attention awareness and then I'm not totally sure what we're gonna do in the last class but what I'm voting for is that the amazing Tas each give a short talk on the cool stuff they're doing but that's under discussion okay that's the Arc of the class um questions
1:13:40
all clear
1:13:43
great well if I have five more minutes maybe I'll do one other little thing let me try this um you asked I'm gonna try to learn everybody's names but I'm not doing that yet because some of you might not show up and I will have wasted a whole piece of my brain encoding it out just kidding um uh but um anyway I remember that you asked like you know gonna read current papers yes it is and you're right it's a it's daunting but let me just say a little bit about how to read papers this
1:14:08
is not a stats course and we haven't prerequisite prerequisited stats neither is is it a course on the physics of MRI so there will be parts of every MRI paper that have a lot of gobbledygook we scanned with this scanning procedure right you know we use this kind of scanner and this kind of blah blah blah lots of gobbledygook you guys don't need to worry about that about the stats it's kind of a judgment call everyone in here should have an idea of what a p level
1:14:36
means and I hope a sense of what a t-test is and an anova if you don't I should probably tell you that offline because that's you know pretty basic but be and what a correlation is beyond that just use your intuitions about those things and we and this is not a course about understanding the details of the stats in each experiment there just isn't room to cover all that in the substance of the studies as well so when you read a paper for example here's a paper
1:15:03
a very old paper you come across this and it's like okay here are all these words like I know it goes on for 20 pages and like how do you even dig in well way to dig in is to start by saying what question is being asked in this paper if the paper is Well written you'll be able to find that in the abstract blah blah blah to study the effect of face inversion on the human fusiform face area okay we'll talk about that more later but if you fish through the abstract you should be able to find what
1:15:30
questions being asked and it's the first thing you should figure out about a paper okay you don't necessarily read a paper you know start to be beginning through the end I think it's better to start with this list of questions in your head and look for the answers to those questions right second question what do they find if the abstract is Well written you can find that in the abstract as well signal intensity from the fusiform face area was reduced when grayscale faces
1:15:56
were presented upside down okay kind of boring but there it is that's a finding this paper okay what is the interpretation like in other words who cares like why who you know who cares about this okay um if you look in here in the abstract FFA responds to faces per se rather than to the low level features present in faces okay we'll talk more about what that means you guys have an assignment about that probably several assignments about that kind of question okay um
1:16:28
next question you want to ask yourself is what is the design of this experiment often for this you have to go beyond the abstract and I should say for even these ques these earlier questions sometimes you won't find them in the abstract that just means the abstract is not well written but that exists okay to get the design like what exactly did they do usually you have to fit and you know what exactly was done and how were the data analyzed you need to fish farther you need to fish around
1:16:55
um other parts of the paper and of course all of those questions okay so I just said okay what question and we just I circled this part but there are many levels to what question so you can get more on you know why why is that inverted question important you look through usually in the introduction to the paper does the FFA respond to faces per se or to a confounding visual feature which tends to be present in faces second is it true that inverted vases cannot
1:17:22
engage face specific mechanisms blah blah blah so that gives you a little more background on what the question is right there are different levels of depth okay so these are all things you want to be looking for when you read a paper what exactly was done we measured MRI responses in the FFA to Upright inverted phases right I don't expect you to understand all this is you're just giving you schematically how you proceed when you're reading a paper okay um more on the interpretation or who
1:17:47
cares right this result would show that face-specific mechanisms are engaged only or predominantly by upright faces blah blah blah right you can fish through for those things point is to have those questions in your head when you read a paper okay it's much it's much more easy and engaging to read something if you have an agenda when you read it and so your agenda in Reading scientific papers is to answer those questions for yourself right uh uh more stuff what was the design and
1:18:14
logic often that's deep in the methods you have to fish around and find it there will be some set of conditions and Designs we'll talk more about all this kind of stuff what exactly was done you know blah blah more details okay and this is my example of the kind of gobbledygook that you can ignore okay so subjects were scanned on a one and a half T scanner and they're all these like this here's the example of God said gobbledygook you can ignore this in this class right every method will have
1:18:44
different kinds of gobbledygook this is MRI gobbledygook you can ignore it okay uh I'm it matters a lot but not here okay uh what else how are the data analyzed if you look in the um you know sometimes there's a data analysis section or a result section or a method section that will tell you you can find that figure it out okay um what was the finding here's more on the finding again you just fish through for these things so the point is just when you're reading a paper you don't
1:19:15
it's not necessarily I think what I do is I read the title I read the abstract and then I start answering those questions for myself and sometimes at that point I'm skipping to figures I'm skipping to methods any of that is fine okay so don't feel like you need to understand each word especially deep in the methods I don't know was that helpful at all we'll try it and you guys will give me feedback and if it works great and if not we'll we'll do more on how to read papers all right
1:19:44
it's 12 25. see you on Monday
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