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Tamara Vanderwal “Gradients go to the movies: The topography and development of large-scale cortical organization during naturalistic viewing”

March 10, 2023
ID
9639

Transcript

  • 00:05Good morning, everyone.
  • 00:06So yes, we're going to look at what happens
  • 00:09when the gradients go to the movies.
  • 00:11So sometimes in my lab we like
  • 00:14to think about. Movies as tasks,
  • 00:16and we start to care a lot about trying
  • 00:18to control what's happening in a movie.
  • 00:21So this is footage from Inscapes where
  • 00:23we very carefully constructed this
  • 00:25state in which we were trying to avoid
  • 00:28social processing, verbal processing,
  • 00:30all these different things.
  • 00:32That's because resting states
  • 00:33actually a task, right,
  • 00:35that some people can't do in this movie,
  • 00:37which is called when Hyder
  • 00:39met Simal Yuri Hesson.
  • 00:41And I wanted to create this
  • 00:43very social but very simple.
  • 00:46Narrative.
  • 00:46So it goes on and on and on
  • 00:48for a little while.
  • 00:49This third movie that you're about to see
  • 00:51is the one that we're working on right now.
  • 00:53It's called all day wrong.
  • 00:56We've busted into live action with this one,
  • 00:59and this is a symptom provocation task,
  • 01:01so you can try to think of what
  • 01:03might we be trying to get at.
  • 01:05So this is a 10 minute OCD
  • 01:07symptom provocation movie.
  • 01:15And she grew and she grew.
  • 01:17So oftentimes we talk about using
  • 01:20movies to decrease noise, right?
  • 01:22So that's things like head
  • 01:24motion changes and arousal.
  • 01:25We talk about trying to drive the signal.
  • 01:27So if I'm interested in certain
  • 01:28circuits or certain symptoms,
  • 01:30I can try to get at that, right.
  • 01:31We're very interested in the
  • 01:33variability that is happening in the
  • 01:34bold signal during movie watching.
  • 01:36We think there's something
  • 01:37quite special going on there.
  • 01:39And then we talk about caring
  • 01:41less about what the movies are
  • 01:43actually doing and using movie
  • 01:45watching itself as a brain state.
  • 01:46So that's what I'm mostly
  • 01:48going to talk about today.
  • 01:50So this question came primarily
  • 01:52from Daniels principal gradient,
  • 01:54which we've seen a lot of.
  • 01:56And the question was what would happen
  • 01:59to the principal gradient if all of those
  • 02:02regions were actually active and engaged,
  • 02:04right?
  • 02:04So if both poles of the gradient,
  • 02:06both hetero modal cortex
  • 02:08and primary sensory cortex,
  • 02:10if those were all active and engaged,
  • 02:12what would happen to the principal gradient?
  • 02:15So my great doctoral student Ahmed Samara,
  • 02:19who I think is on zoom, took on this project.
  • 02:22He used the HCP data set,
  • 02:24which you can see the structure of here.
  • 02:26This is very much taking movie
  • 02:28watching as a brain state, right.
  • 02:30We have four different 15 minute movie
  • 02:32runs and during each run there's like
  • 02:34little snippets of different movies,
  • 02:36so three minute clips,
  • 02:385 minute clips,
  • 02:39whole bunch of different stuff.
  • 02:40So we're just kind of kitchen
  • 02:42sinking the brain.
  • 02:44And we were able.
  • 02:45And I had fun with this because you
  • 02:47can't usually do this when you're
  • 02:48working with kids, but we could take.
  • 02:52Both sets of data, both conditions,
  • 02:55make them perfectly equal
  • 02:56with regard to head motion.
  • 02:57Normally I don't get to do that,
  • 02:58so that was fun.
  • 03:00And also perfectly controlled
  • 03:01for the amount of data.
  • 03:02So the number of volumes in each of these,
  • 03:04right?
  • 03:05So these are these pristine functional
  • 03:07connectivity matrices for each condition,
  • 03:09about 45 minutes,
  • 03:1050 minutes of data in each of those.
  • 03:14So then we just basically run
  • 03:16our vanilla at this point,
  • 03:18diffusion embedding dimensionality
  • 03:20reduction to get our gradients.
  • 03:23And what do we find?
  • 03:24We find that across conditions,
  • 03:26the components are basically explaining
  • 03:29very similar amounts of variance.
  • 03:31We recapitulate our classic
  • 03:34resting state gradients,
  • 03:36and what do we start to see
  • 03:38when we get to movies?
  • 03:39So some interesting differences,
  • 03:41right?
  • 03:42First of all,
  • 03:42the sensory motor regions jump out the same,
  • 03:45so that looks familiar,
  • 03:47but there's some differences there.
  • 03:49One difference that we're gonna see
  • 03:51throughout these movie gradients
  • 03:53is that the hetero modal pole
  • 03:54is not just default network,
  • 03:56it is equally occupied by both frontal,
  • 03:58parietal and default regions.
  • 04:00So we think that's pretty interesting.
  • 04:03You also see on that that the
  • 04:05visual regions have shifted to
  • 04:07the middle of the gradient.
  • 04:09Gradient 2 is what we kind of call
  • 04:11this visual to non visual gradient.
  • 04:13That's a little bit of an oversimplification,
  • 04:16but you can kind of see what
  • 04:18we're talking about big picture.
  • 04:20And then our favorite gradient
  • 04:22is this movie gradient 3.
  • 04:24And there's a few reasons why we're
  • 04:26jazzed about this one right now.
  • 04:28But it's unique.
  • 04:29So this one does not show up really
  • 04:31in a recognizable form at all
  • 04:33in the resting state gradients.
  • 04:35And it combines some, you know,
  • 04:38primary auditory regions, but all of your.
  • 04:41Auditory language processing regions,
  • 04:43some of which are a little bit
  • 04:45more higher order and it's giving
  • 04:46them all the same gradient score.
  • 04:48So it is grouping those things all
  • 04:50together and they're anchoring that gradient,
  • 04:53right.
  • 04:53So this is a unique and we call this
  • 04:56auditory language movie gradient.
  • 04:59We can take the lowest 10% of those
  • 05:03scores and we can do some neuro synth
  • 05:05mapping and you can see that these are
  • 05:08very functionally segregated, right?
  • 05:12So this is interesting.
  • 05:13All of a sudden we don't have,
  • 05:15we have hierarchical gradients still,
  • 05:18right that that principle is the same,
  • 05:20but we now have this different
  • 05:22level of granularity.
  • 05:24So as someone who wants to study development
  • 05:26and different psychiatric populations.
  • 05:29The question becomes,
  • 05:30does this granularity get us anything right?
  • 05:32So some of the studies in
  • 05:34gradient work that have looked at,
  • 05:36say,
  • 05:36chaotic populations,
  • 05:37generally what they're finding is
  • 05:39a squashed principal gradient.
  • 05:41So in depression you have a
  • 05:43squashed principle gradient.
  • 05:43In autism you have a
  • 05:45squash principle gradient.
  • 05:46If we have these three gradients to look at,
  • 05:49do we start to see a little
  • 05:51bit of differentiation or can
  • 05:53we tell a different story?
  • 05:54So thinking about development,
  • 05:55we thought just based on what we
  • 05:58know about cortical development,
  • 06:00both functionally and structurally,
  • 06:01that in kids probably those first two
  • 06:04gradients would look pretty much the same.
  • 06:06But we thought maybe our special
  • 06:08movie gradient #3,
  • 06:09the the auditory language gradient,
  • 06:11might show some differences.
  • 06:15So we will cut to the chase and show
  • 06:17you this is now jumping data set.
  • 06:19So this is in the healthy brain
  • 06:21network biobank.
  • 06:21These kids watched 10 minutes
  • 06:23of Despicable Me and about 3
  • 06:261/2 minutes of the present.
  • 06:27And what you can see here and I'm
  • 06:29not showing you but will we will
  • 06:31eventually that the first two
  • 06:32gradients look pretty much the
  • 06:34same across kids and adolescents.
  • 06:36But when you get to this
  • 06:38auditory language gradient,
  • 06:38you start to see these very
  • 06:41interesting differences.
  • 06:42And so Ahmad's point about this.
  • 06:44Is that when you're in the kids?
  • 06:46This is very much.
  • 06:48And auditory gradient and as you
  • 06:50progress through development though
  • 06:52these are cross-sectional data,
  • 06:54you get to see the the different
  • 06:56higher order regions and these
  • 06:58different language processing
  • 06:59regions are now part of the gradient.
  • 07:02They weren't when you were a little kid.
  • 07:06So we're going to do one more thing.
  • 07:08This is a garbage can that I pass
  • 07:10on my way to work every morning.
  • 07:12My skull is a cage,
  • 07:13and I yearn to wander. So good.
  • 07:19So we are going to go out of the
  • 07:22skull and into gradient space.
  • 07:24So we can look,
  • 07:25this is back in the adult data now
  • 07:27and we can look at the transitions
  • 07:29within this with ingredient
  • 07:31space between these two states.
  • 07:32And So what we thought we were seeing was
  • 07:35that some regions were moving far right
  • 07:38from rest to movie and some were not.
  • 07:41So we just computed the distance
  • 07:43that each region was moving
  • 07:44within this space and then we can
  • 07:47map that back onto the cortex.
  • 07:49And what you see is this like very
  • 07:52clear clustering around the STS.
  • 07:53But those are the regions that within
  • 07:56gradient space are traversing a really
  • 07:58far distance when you do these stage shifts.
  • 08:01So kind of interesting.
  • 08:02So this work right now is on bio archive.
  • 08:05We just submitted the revisions,
  • 08:07you can check that out if you want.
  • 08:09We also looked at the reliability of it
  • 08:11and did some brain behavior stuff too.
  • 08:13So I will stop by saying thank you
  • 08:15to my lab and to everybody else.
  • 08:18And then this.
  • 08:19Did I do this?
  • 08:20Yeah, this one's for Doctor Brakey,
  • 08:22because I don't feel like we got
  • 08:23enough press for our beautiful cover.
  • 08:25So I'm just going to leave that up now,
  • 08:27and I'm happy to answer any questions.
  • 08:38I was wondering. Don't get very focused.
  • 08:46Like familiarity with the movie
  • 08:47that they're watching the scanner.
  • 08:50Yeah. So I think novelty is something that
  • 08:53we haven't systematically looked at yet.
  • 08:55I would point out that in tasks,
  • 08:57there are massive novelty effects
  • 08:59that we don't ever talk about.
  • 09:01Resting state. Are there novelty effects?
  • 09:03We don't seem to care, right?
  • 09:04But I do think we should look at it.
  • 09:06My my gut would be that in kids,
  • 09:10the novelty effect would
  • 09:11actually be very small, right?
  • 09:13So kids have an amazing
  • 09:15appetite for repetition.
  • 09:16They want to see it again, see it again,
  • 09:18see it again, and they just don't care.
  • 09:19They're in. They're as interested.
  • 09:21The 70th time as they were the first time.
  • 09:23So I think we'd actually have
  • 09:25a smaller novelty effect.
  • 09:26But yeah, we should look at it.
  • 09:29Do you think that?
  • 09:31Find the data set where you're.
  • 09:36The same.
  • 09:40Yeah, so it's a really neat question.
  • 09:42We're just starting to collaborate
  • 09:45with Garov Patel's lab in Columbia.
  • 09:47They have an amazing data set where
  • 09:50individuals with schizophrenia
  • 09:52watched listen to stories.
  • 09:54So they have an auditory
  • 09:56only naturalistic condition,
  • 09:58and then they watch a movie,
  • 09:59but without the auditory stuff.
  • 10:02So that's super weird, right?
  • 10:04So you're watching everything
  • 10:04and you see the mouse moving,
  • 10:06but you're not hearing the soundtrack.
  • 10:08So they have these three.
  • 10:09You know, different.
  • 10:10So they're starting to
  • 10:10look at and so we have,
  • 10:12we want to look at the gradients
  • 10:13and those and see what happens.
  • 10:16Curious so.
  • 10:19I noticed how.
  • 10:22Things out all the time.
  • 10:24When you got a movie to watch
  • 10:26the actual content in the sound.
  • 10:27I don't know how much of a difference
  • 10:29that you see here about the fact that
  • 10:30you're getting kind of bombarded
  • 10:31by effectively noise during the
  • 10:33rest of the study during the task
  • 10:35that that construction information.
  • 10:36How do you even go about finding
  • 10:38people that it's really.
  • 10:41Yeah, it's a really big deal, right.
  • 10:43So music is a massive part of our brains
  • 10:45and our functioning and our hearing things,
  • 10:47and in a movie it's a really big deal.
  • 10:50So a lot of people who have used inscapes.
  • 10:52Do it without sound, which to me like
  • 10:54that's a whole different paradigm.
  • 10:56Yeah, you could.
  • 10:57You could definitely look at that and I
  • 11:00think there'd be significant effects. Ohh.
  • 11:04And this is the best.
  • 11:09One of the best, probably the best.
  • 11:13Amazing job. It only took us what? Two years.
  • 11:19If you go back to the slide,
  • 11:21I mean it looks to me like that.
  • 11:23Yeah, one more. Yeah, this looks
  • 11:24like it's been 3 dimensional space.
  • 11:26It's just. Yeah, really. Have you?
  • 11:35Yeah, so you can look at them.
  • 11:38Right, so we started looking at
  • 11:40them just in like flat space.
  • 11:41So this is gradient 1 by gradient 2.
  • 11:44I get all geeked out about this
  • 11:45because I think this starts to
  • 11:47look like a more perfect gradient.
  • 11:48So Daniel and I like to argue about
  • 11:51which is the most perfect gradient.
  • 11:53Definitely look at that, right.
  • 11:55We did like all these measurements
  • 11:57like distance to nearest
  • 11:58neighbor really equal in movies.
  • 12:00So step wise distance between all
  • 12:01of those points is very, very,
  • 12:03very similar in movie distance to centroid,
  • 12:06we did all those sorts of stuff.
  • 12:08Yeah, I think it's really interesting.
  • 12:11It's like there's this apex triangle, right?
  • 12:14So you have these three
  • 12:15hierarchical gradients that go up.
  • 12:17So we sort of think of it like
  • 12:19the three movie gradients are
  • 12:21represented in the principal gradient.
  • 12:23But it's just. Collapsed almost.
  • 12:27And so if you rotate it,
  • 12:28then you can see all three of them.
  • 12:29But it is it.
  • 12:30Is it the same information or not?
  • 12:33I don't know.
  • 12:34We're still trying to figure it out.
  • 12:362nd.