Speaker 1: Oh hey, it's the fountain at the mall that's never on,
Speaker 1: Ali Ward, and you're here for your brain, so am
Speaker 1: I let's get into it. So this ologist was recommended
Speaker 1: years ago and has been on my list forever, but
Speaker 1: I wanted to scoot on down an hour south of
Speaker 1: LA to his office on the UC Irvine campus where
Speaker 1: he does a lot of very cool and important work
Speaker 1: studying brains. How does one become that? While an undergrad
Speaker 1: in neuroscience and a master's in psychological and brain sciences
Speaker 1: from John Hopkins University, where he was later an assistant professor,
Speaker 1: he got his PhD from u SE Irvine, and then
Speaker 1: he returned there to become the director of the Center
Speaker 1: for the Neurobiology of Learning and Memory. Dude knows memory.
Speaker 1: Everyone in his office was so nice and I got there.
Speaker 1: We posted up at his desk, and at one point
Speaker 1: I looked over to see some artwork of a seahorse,
Speaker 1: and I was like, okay, And then I realized, oh, okay,
Speaker 1: We're going to touch on that in a bit. But first,
Speaker 1: thank you to all the patrons who submitted questions for
Speaker 1: this episode. We're going to cover Walts Wall in part
Speaker 1: two next week. And because this is just a huge topic,
Speaker 1: there's so many good questions. Thank you to everyone getting
Speaker 1: ologies merch from Ologiesmarch dot com. Thanks to everyone leaving
Speaker 1: us for reviews, which boosts the show so much. And
Speaker 1: each week I remember to read them all and I
Speaker 1: pick it just written one such as this one from Lucygoose,
Speaker 1: who wrote that they drove for seven days to Alaska
Speaker 1: from the lower forty eight states and ologies made the
Speaker 1: ten hour days pass quickly. Lucy Goose, I hope we
Speaker 1: saw a moose and now onward.
Speaker 2: Okay.
Speaker 1: Naem Anology is not a word that this guest really
Speaker 1: likes because someone else wrote a book using it. He
Speaker 1: has nothing to do with the book and that person's
Speaker 1: Google alerts rip. It's going to get screwed up because
Speaker 1: of this. But niemnology is the study of memory, and
Speaker 1: it comes from the Greek for something used to help
Speaker 1: in remembering a thing, which is what I suppose your
Speaker 1: brain function is, among other things.
Speaker 3: So let's get into how.
Speaker 1: It does, as well as discussed movie myths, aging and
Speaker 1: memory loss, childbirth amnesia where your memory is stored, what
Speaker 1: happens when you cram for a test or a presentation,
Speaker 1: hormones and memory, the movie Lucy. How to know if
Speaker 1: you're losing your mind, that thing where you can't remember
Speaker 1: a word? What memory is even for? How to let
Speaker 1: go of the past, remembering people's names, neurodivergence, collective mis remembering, dementia, Alzheimer's,
Speaker 1: and so much more with neurobiologist Professor Researcher, director of
Speaker 1: UC Irvine's Center for the Neurobiology of Learning and Memory.
Speaker 1: And I'm sorry, neemonologist, doctor Michael Yassa, and I'm going
Speaker 1: to make you hold your mic a little bit like this, Mike.
Speaker 4: Mike is perfectly fine. I am not very formal at all.
Speaker 3: I'll just call you Doc. How's that.
Speaker 4: I think anything aside from Mike would just make me
Speaker 4: feel very strange.
Speaker 2: But Doc is fine. Doc is fine. That's okay.
Speaker 3: As someone who studies memory and neurobiology, do you get
Speaker 3: put on the spot a lot about memory? Do you
Speaker 3: tell people at dinner parties like what you do? Or
Speaker 3: will you just be diagnosing people without you?
Speaker 2: Oh my gosh.
Speaker 4: If the question comes up like NonStop the minute I
Speaker 4: say that I'm a neuroscientist or I study the brain,
Speaker 4: even if I don't say anything about memory. The first
Speaker 4: thing they'll tell me about is how poor their memory is,
Speaker 4: of course, or they'll ask me about what is this
Speaker 4: what is this thing that happens when I just have this,
Speaker 4: you know, thing at the tip of my tongue and
Speaker 4: I just can't come up with it. And then all
Speaker 4: of a sudden, when I'm not thinking about it, it
Speaker 4: comes to mind. I'm like, yeah, tiput a tongue phenomenon.
Speaker 4: I try to tell them a little bit about how
Speaker 4: that works.
Speaker 1: We'll get to it.
Speaker 4: So it's a great, you know, conversation to have on
Speaker 4: a plane at a dinner party.
Speaker 2: But it's not stop. Everyone wants to find out about
Speaker 2: their brain.
Speaker 3: Tell people that you do something else.
Speaker 2: Well, it's interesting.
Speaker 4: If I tell them I'm a professor, then I have
Speaker 4: to explain, well, you know, I do a little bit
Speaker 4: of teaching, but really I'm doing mostly your research, right,
Speaker 4: But I think that that's sort of a secondary thing
Speaker 4: they think about in terms of professors, But really you're
Speaker 4: there to teach. But I quickly pivot from what I
Speaker 4: teach to what I do research on, and then the
Speaker 4: interesting questions come about. Sometimes people will tell me about
Speaker 4: family members, or we'll ask all sorts of interesting questions,
Speaker 4: and every now and then something out of left field.
Speaker 4: I'll give you a great example. This is one of
Speaker 4: my favorites and it's now come up several times when
Speaker 4: they ask me about whether there are memories that are
Speaker 4: stored outside of the brain, can the heart, or in
Speaker 4: the liver or some other body organ And the first
Speaker 4: time that I heard that question, I didn't know what
Speaker 4: to do with it. I sort of laughed and thought, Okay,
Speaker 4: you must be joking, And then I looked it up
Speaker 4: and there's definitely some folks who do think that, and
Speaker 4: it's not clear exactly what's happening. You know, they talk
Speaker 4: about like triansplant cases. But you know, at the end
Speaker 4: of the day, we have to be simplified a little
Speaker 4: bit in our thinking. Think this is science, and all
Speaker 4: of the data that we have on memory and how
Speaker 4: it works emanates from the brain, so that is where
Speaker 4: things live.
Speaker 3: So I've heard those cases where I never liked donuts
Speaker 3: before I had a kidney transplant and it turns out
Speaker 3: they loved donuts and things like that, or somatic memories
Speaker 3: or sematic therapies.
Speaker 1: And researchers call this clinical manifestations of body memories. And
Speaker 1: one twenty twenty one study insular cortex neurons encode and
Speaker 1: retrieve specific immune responses, found that the brain's insular cortex
Speaker 1: stores immune related information and that in mice, those who
Speaker 1: had episodes of this induced colitis for the study could
Speaker 1: reexperience that intestinal inflammation just by having the insular neurons reactivated.
Speaker 1: And the twenty twenty two paper Clinical Manifestations of Body
Speaker 1: Memories the Impact of Past bodily Experiences on Mental Health
Speaker 1: cited that study and explained that the findings indicate that
Speaker 1: memory alone can activate the immune system in the absence
Speaker 1: of an outside trigger. So, in other words, the brain
Speaker 1: remembered an old infection and generated the inflammatory disease on
Speaker 1: its own by reactivating a specific memory trace of the
Speaker 1: past bodily immune response. And as will not surprise you,
Speaker 1: there's a lot left to research in this realm and
Speaker 1: it's fascinating. But wait, what were we talking about?
Speaker 3: But I want to go back to the tip of
Speaker 3: the tongue phenomenon because that was one of my questions.
Speaker 4: Of course, I mean, I can maybe with a little
Speaker 4: bit more detail later, but I can tell you that
Speaker 4: it's a very innocuous thing. It doesn't mean anything is
Speaker 4: wrong with your brain. It doesn't mean that it's, you know,
Speaker 4: on a decline or anything like that. It happens all
Speaker 4: the time, and largely because we are distracted and there
Speaker 4: are many things that are competing for our attention at
Speaker 4: any given time, even thoughts and our brains constantly compete
Speaker 4: for attention. So every now and then you have sort
Speaker 4: of a little bit of a failure of recall. You know,
Speaker 4: the memory is there, but it's an issue of access,
Speaker 4: and you have to kind of clear some of the
Speaker 4: clutter to be to access it appropriately. And a lot
Speaker 4: of times that happens when your brain quiets a little bit,
Speaker 4: when you're not distracted by the current things that are
Speaker 4: happening in the conversation. That's why it comes back later
Speaker 4: when you're sort of least thinking about it. Of course,
Speaker 4: your brain doesn't actually stop thinking, but it surprises you
Speaker 4: sometimes when it comes up later.
Speaker 1: So this phenomenon of something being on the tip of
Speaker 1: your tongue is called tip of the tongue phenomenon, according
Speaker 1: to a nineteen sixty six Journal of Verbal Learning and
Speaker 1: Verbal Behavior article titled the tip of the tongue Phenomenon.
Speaker 1: But it's also known as lethologica, and according to this
Speaker 1: twenty twenty four paper coordinating words and sentences detecting age
Speaker 1: related changes in language production. Sure, it can become more
Speaker 1: common as we age, but it's also very normal and
Speaker 1: can be considered just the I'm tired and I have
Speaker 1: too much going on in my brain right now phenomenon.
Speaker 1: But we'll get to memory loss later. We're just getting started.
Speaker 1: And this is a two parter.
Speaker 3: Does meditation help your brain if you can try to
Speaker 3: calm it or quiet it.
Speaker 2: Yeah, that's a great question.
Speaker 4: So meditation has a lot of benefits for them, certainly
Speaker 4: to be able to remove distractors, to think a little
Speaker 4: bit more coherently about major things that are occupying your consciousness.
Speaker 2: It helps you do that. I don't know if there's.
Speaker 4: Any rigorous studies that have been done on whether or
Speaker 4: not meditation, for example, helps with a tip of tongue phenomenon,
Speaker 4: particularly because it's difficult to elicit, right. It's like when
Speaker 4: it happens, you know, you're surprised by it and you say, oh,
Speaker 4: that just happened, but you can't exactly trigger it in
Speaker 4: a laboratory setting and study it in detail. That way,
Speaker 4: so we have to just rely on when it happens,
Speaker 4: Like we ask, well, what's the circumstance, what is the
Speaker 4: situation that you're in? And my guess is if one
Speaker 4: could do a rigorous study, you would see that meditation
Speaker 4: likely helps with that.
Speaker 3: I'm finding it does happen to me more and more
Speaker 3: often as I'm older, where I'll hear a song and
Speaker 3: before I could tell you exactly who's saying it, and
Speaker 3: now I go and I can't, and I'm wondering in
Speaker 3: that moment if my brain is just like a bruised apple,
Speaker 3: just full of spots.
Speaker 2: That's a good one.
Speaker 4: I've never thought about a bruised apple analogy before, but
Speaker 4: you know, you mentioned as we get older, and I
Speaker 4: think that's part of it. But we're also busier and
Speaker 4: our sleep gets disrupted and all sorts of things. I mean,
Speaker 4: just think about the twenty four hour news cycle and
Speaker 4: all the things that are constantly competing for our attention.
Speaker 4: So we've become just in general, much more distractable. I
Speaker 4: think this generation of teenagers and children even more and
Speaker 4: more distractable, So that likely will happen more often, even
Speaker 4: absent any sort of aging phenomena. Right, But as we
Speaker 4: get older, our ability to be able to function, and
Speaker 4: you know, notwithstanding all of these distractions also is difficult
Speaker 4: becomes more difficult.
Speaker 3: Well, as a neurobiologist, someone who is such an expert
Speaker 3: in this field, is now a good time to be
Speaker 3: studying memory because things are changing so much of our
Speaker 3: attention in our brains? Or is it so frustrating because
Speaker 3: it changes based on like the TikTok algorithm.
Speaker 4: So when I first started to get interested in neuroscience,
Speaker 4: it wasn't clear to me how quickly our knowledge would change.
Speaker 2: Now.
Speaker 4: Of course, when I teach students in undergraduate courses, I
Speaker 4: always tell them, look, I'm going to tell you, you know,
Speaker 4: mostly textbook versions of things, but there are many things
Speaker 4: that are past the textbooks, Like these textbooks are already
Speaker 4: obsolete by the time they're coming out because neuroscience.
Speaker 2: Advances so quickly. So what I tell you is likely.
Speaker 4: Going to be right like ninety percent of the time
Speaker 4: in ninety percent of cases. But there's that additional, really
Speaker 4: interesting ten percent that we've essentially just tossed out the
Speaker 4: textbook over the last few years. And that continues, and
Speaker 4: it actually continues at a very rapid clip. So I've
Speaker 4: been doing this for almost a quarter century now, and
Speaker 4: in the last five years, the advances that I've seen
Speaker 4: in neuroscience and the study of memory have been so
Speaker 4: much more substantial than the previous twenty years. And that's
Speaker 4: because our technology is better, our equipment is better, the
Speaker 4: ability to record from more cells in the brain at
Speaker 4: the same time, and our ability to process just incredible
Speaker 4: amounts of data with artificial intelligence, machine learning soon quantum computing.
Speaker 4: All of those advances have had a tremendous impact on
Speaker 4: how quickly this field has moved. So I used to
Speaker 4: be able to tell people here's what I anticipate will
Speaker 4: be the case in five years. Now I can't do
Speaker 4: it anymore. Just I cannot predict because every time that
Speaker 4: I've tried, I've realized five years later, Wow, we've moved
Speaker 4: so much faster than I ever anticipated. So if you
Speaker 4: ask me what I think is going to happen in the
Speaker 4: next five years of neuroscience, I have no idea.
Speaker 2: The sky is the limit?
Speaker 1: Is it limitless? Okay, we're going to get to some
Speaker 1: whack brain movies in a bit as well, But yes,
Speaker 1: neuroscience is moving faster and faster and faster, as our
Speaker 1: brains are also getting more and more crowded with distractions
Speaker 1: and information. Every day, we're just zooming on this motorbike
Speaker 1: of knowledge in the fast lane, carrying all our luggage
Speaker 1: on our backs. I'm so tired and scared.
Speaker 3: Well, we don't know the future, but what about the past?
Speaker 3: How did you become a brain doctor? How did you
Speaker 3: become someone who wants wanted to research the brain using
Speaker 3: your brain?
Speaker 4: Yeah, it's like, why do I want to think about thinking? Yeah,
Speaker 4: there's something so very beautiful and meta about this. You know,
Speaker 4: it wasn't always something that I envisioned myself doing. So
Speaker 4: when I was an undergraduate first starting out, I did
Speaker 4: my undergraduate training at Johns Hopkins and I was a
Speaker 4: pre med major. That's what a lot of students go
Speaker 4: there to study. And you have this idealized version of
Speaker 4: the future. Right, I want to be a doctor. I
Speaker 4: want to help people. And I remember very vividly two
Speaker 4: things happened in quick succession. When I was in my
Speaker 4: sophomore year of college, I took a class in the
Speaker 4: Department of Cognitive Science called Mind's Brains and Computers. And
Speaker 4: I remember this so vividly because nineteen ninety nine was
Speaker 4: the year that the first Matrix came out, and one
Speaker 4: of my assignments for that course was to go watch
Speaker 4: The Matrix. Now, at the time, I thought, okay, this
Speaker 4: is crazy. I'm being asked to go watch a movie
Speaker 4: for an assignment. What could be better? This is like
Speaker 4: the best life of an undergraduate. So I went, and
Speaker 4: of course if any of your listen haven't seen, the
Speaker 4: Matrix is some must watch, especially the original Matrix is
Speaker 4: the world that has been pulled over your eyes to
Speaker 4: blind you from the truth. And it was transformative because
Speaker 4: I think one of the major themes was could you
Speaker 4: understand the brain and its functions so well that you
Speaker 4: can build a completely artificial simulation of the reality around it,
Speaker 4: and the brain wouldn't know a difference, so it would
Speaker 4: be immersed in exactly the same way. It would have
Speaker 4: no idea that this is actually an alternate reality or
Speaker 4: a simulation. Who Now, that requires that you understand the
Speaker 4: brain at a fundamental level so well that you can
Speaker 4: fool it into believing this is a you know, a reality,
Speaker 4: And that was part of the assignment, is you know,
Speaker 4: what do we need to understand about the fundamental rules
Speaker 4: of brain operation to be able to enable something like
Speaker 4: the matrix, and the notion, of course, of like living
Speaker 4: in a simulation was just so interesting. At times I
Speaker 4: still think maybe maybe.
Speaker 3: I have no idea.
Speaker 5: I hope so.
Speaker 2: But it was at that.
Speaker 4: Moment that I realized, you know, as a pre medical
Speaker 4: student who is interested in studying biology, studying the human body,
Speaker 4: all of those things, and this was my first foray
Speaker 4: into the brain, and I was captivated by the fact
Speaker 4: that we just had no idea. We weren't even close
Speaker 4: to having a complete understanding of how the brain operates.
Speaker 4: We understood a lot about the heart, about the lungs,
Speaker 4: about the kidneys. You know, you have a pump in
Speaker 4: the heart, right, you have a filter in the kidneys.
Speaker 1: And yes, we just put out an episode about veins
Speaker 1: and arteries, and also we have one about kidneys and pea. Now,
Speaker 1: there's so much we don't know about the human body
Speaker 1: and quantum physics and how long we'll survive as a
Speaker 1: species and if there are aliens. But let's just try
Speaker 1: to stick right now to the bowl of oatmeal that
Speaker 1: you think with.
Speaker 4: But with the brain, it seemed like we knew a
Speaker 4: tiny fraction of a fraction of what we need to
Speaker 4: know to really fully understand it. So that became really exciting.
Speaker 4: And then I started working in a research laboratory and
Speaker 4: the department of psychiatry, so I started to see patients
Speaker 4: with a variety of brain conditions, and you know, I
Speaker 4: was an assistance on a number of research projects where
Speaker 4: I got this the impact of what brain research could
Speaker 4: really allow us to do, so shifted gears. Didn't want
Speaker 4: to go to med school anymore. I was captivated by
Speaker 4: the thought of I wanted to be a brain scientist
Speaker 4: and spend the rest of my life doing this because
Speaker 4: I think I can make a career out of it
Speaker 4: and study it for a good You know, however, many
Speaker 4: decades without really getting to an endpoint. And I was
Speaker 4: also always and continue to be a perpetual student. So
Speaker 4: the idea that knowledge is going to evolve and change
Speaker 4: that wasn't as scary to me as it might be
Speaker 4: for maybe some others. So that's what got me into it.
Speaker 4: And now, you know, twenty five years later, I can say, like,
Speaker 4: we know a lot more, but it still remains a
Speaker 4: small fraction of what we stand to know.
Speaker 3: When you were studying neuroscience and you were studying how
Speaker 3: memory works. Did you have any hacks to remember what
Speaker 3: you were learning?
Speaker 4: This is your way of asking me, what can I
Speaker 4: do to improve my learning? So, yes, there are a
Speaker 4: few things, but interestingly enough, we knew those not based
Speaker 4: on neuroscience. We knew it based on mostly experimental psychology.
Speaker 3: I gotta do that episode.
Speaker 4: So psychologists for the longest time, since the eighteen hundreds,
Speaker 4: have been very, very good at trying to understand how
Speaker 4: to optimize our memories, how to think about forgetting, why
Speaker 4: does forgetting happen?
Speaker 2: And so on. The neuroscience gives you tools to.
Speaker 4: Understand the mechanisms that lead to that, and that's really important,
Speaker 4: of course for us to be able to change it
Speaker 4: and optimize it and intervene. Certainly in the context of
Speaker 4: diseases that's important, But in a day to day sort
Speaker 4: of learning setting, most of what we know still goes
Speaker 4: back to experimental psychology.
Speaker 2: I'll give you a couple of examples.
Speaker 4: One is what we call this spacing effect. So when
Speaker 4: I teach students about this, I tell them this is
Speaker 4: my no cramming rule, right, And the idea is that
Speaker 4: if you stack all of your learning into one learning episode.
Speaker 4: You may do well if your tested, say an hour
Speaker 4: later or you know, two hours later, but you're going
Speaker 4: to quickly forget all of that material. Oh cool, And
Speaker 4: that's why cramming doesn't work for the long term. Although
Speaker 4: and I shouldn't maybe say this, but I'll disclose it anyway,
Speaker 4: if you really want to do well on an exam,
Speaker 4: still it does work to some extent. But if you
Speaker 4: have like a cumulative evaluation in that course, you know,
Speaker 4: best of luck. So spacing your study sessions becomes really important.
Speaker 4: And some of that also is how much learning your
Speaker 4: brain naturally does when you're sleeping at night. It's constantly
Speaker 4: replaying memories of things that you've learned during the day
Speaker 4: and trying to consolidate that or kind of solidify it
Speaker 4: and make it resistant to forgetting.
Speaker 3: Yes, rest is important for remembering stuff.
Speaker 4: So the more that you interspace your study sessions and
Speaker 4: you have like some sleep in between them, the better
Speaker 4: off your learning is going to be for the long run.
Speaker 4: So that's one that we've known for some time. The
Speaker 4: other one that is really really cool actually comes from
Speaker 4: the notion that has been entertained I think in the
Speaker 4: education realm for some time, it's the idea that you
Speaker 4: may be a visual learner, or like an auditorial learner,
Speaker 4: or a kinesthetic learner. And the reality is that this
Speaker 4: is all myth. There is no such thing as learning styles.
Speaker 4: Whether I know, and you're giving me the same exact
Speaker 4: look that I get when I talk to teachers. The
Speaker 4: reality is, if you do the right experiments, you'll uncover
Speaker 4: the fact that there's no such thing as a learning style. Now,
Speaker 4: what is the case is that the more senses that
Speaker 4: you involve in your learning, the more you engage what
Speaker 4: we call multimodal learning, so both visual and auditory and
Speaker 4: maybe kin esthetic, the better off your recall is going
Speaker 4: to be later on.
Speaker 1: And this can also be called multimodal learning theory. But
Speaker 1: author and Harvard developmental psychologist and research professor Howard Gardner
Speaker 1: founded this theory decades ago of multiple intelligences, which breaks
Speaker 1: down strengths in areas like physical movement and being word smart,
Speaker 1: and nature smart and photo smart and interpersonal smart. And
Speaker 1: some educators have adopted parts of that multiple intelligences theory
Speaker 1: to teach using various senses to appeal to different types
Speaker 1: of intelligence, but many researchers are very squiky about that,
Speaker 1: including Gardner himself. So while the notion of learning styles
Speaker 1: are a myth, engaging more senses can help with recall.
Speaker 4: Because you're engaging more the senses, you're essentially giving your
Speaker 4: brain more bits and pieces to connect this memory to.
Speaker 4: So any number of those bits and pieces can retrigger
Speaker 4: that memory and allow you to recall it. You're giving
Speaker 4: it more routes to retrieval essentially, So that's something else. Again,
Speaker 4: we've known this from experimentals that calls you. We didn't
Speaker 4: need neuroscience, we didn't need fancy brain imaging and some
Speaker 4: one to tell us all that. We just knew it
Speaker 4: simply from practice and behavior. So that's another really fun
Speaker 4: one that I realized early on.
Speaker 3: Well, let's get down to what memory is and where
Speaker 3: in the brain it's stored. I know, the hippocampus is
Speaker 3: very important.
Speaker 1: So the hippocampus is a googly little C shaped part
Speaker 1: of the brain. It's tucked into the temporal lobe. Actually
Speaker 1: you have two of them, and the hippocampus is a
Speaker 1: major part of the system that makes short memories into
Speaker 1: longer term ones, and damage to it via something like
Speaker 1: Alzheimer's disease can result in memory loss and dementia. But
Speaker 1: a more fun effect is that hippocampus means seahorse, because
Speaker 1: if you were to take yours out of your brain,
Speaker 1: it would resemble a sea horse or like a very
Speaker 1: big chicken embryo, kind of a lumpy head region and
Speaker 1: a weird long tail. It's very slippery looking. But what
Speaker 1: parts of our brains are we filing it? And how
Speaker 1: does it stick?
Speaker 4: Yeah, So the question of where does memory get stored,
Speaker 4: and there's a number of answers to this. It all
Speaker 4: depends on the type of memory. It turns out that
Speaker 4: memory is no one size fits all. So remembering our
Speaker 4: conversation that we're having now, say tomorrow, that's one type
Speaker 4: of memory. But remembering how to tie your shoelaces or
Speaker 4: how to ride a bicycle that's a different kind of memory,
Speaker 4: and it tends to engage different systems in the brain.
Speaker 4: So there are procedural things that take a lot of
Speaker 4: trial and error and practice. This that tends to get
Speaker 4: stored in some systems and the brain typically not the
Speaker 4: hippo campus actually, And then there's experiences that are somewhat
Speaker 4: autobiographical or what we call episodic memories, memories for events
Speaker 4: that happen, people that you meet, names, faces, all this
Speaker 4: kind of stuff, and that does rely on the hippo campus,
Speaker 4: at least initially. Over time, memories tend to get strengthened
Speaker 4: and the hippocampus starts to create connections with essentially everywhere
Speaker 4: else in the brain, so that memory has become much
Speaker 4: more resistant to loss because they're stored in a much
Speaker 4: more distributed way throughout the brain. So when you ask
Speaker 4: the question where do memories get stored? I ask the
Speaker 4: counter question, which is where does it not get stored.
Speaker 4: It's sort of everywhere, right, And depending on the kind
Speaker 4: of memory, some regions may be more involved than others.
Speaker 4: But the reality is all of your brain is capable
Speaker 4: of what we call plasticity, which is essentially changing the
Speaker 4: way it functions or the way that it connects with
Speaker 4: other regions and other cells, as a function of learning,
Speaker 4: as a function of exposure to something in the environment,
Speaker 4: something that's happening in the world.
Speaker 1: So memories are less like one big, overflowing treasure chest
Speaker 1: hidden in a specific crawl space of your brain. It's
Speaker 1: more like if a shipwreck scattered coins all over the
Speaker 1: beach of your consciousness.
Speaker 3: So you might have a memory of a chocolate Sunday
Speaker 3: you had when you were twelve after a baseball game,
Speaker 3: and it might be in one part of your brain.
Speaker 3: It might be in the occipital lobe or the temporal
Speaker 3: lobe or.
Speaker 4: Yeah, so let's take that example. That's a great one.
Speaker 4: So if you think about that ice cream Sunday, the
Speaker 4: experience of having that, certainly there were visual elements looking
Speaker 4: at it's maybe the person who bought it for you
Speaker 4: or whoever it is. There may have been some auditory
Speaker 4: things that you might link to it. If it was
Speaker 4: a baseball game, there may be some things happening around it.
Speaker 4: Certainly there's the taste and the memory of that as well,
Speaker 4: there's an emotional context that might have been such such
Speaker 4: a pleasurable experience that kind of generated some some emotional
Speaker 4: reaction that you maintained. All of those bits and pieces
Speaker 4: are stored in different places.
Speaker 2: It's all over the place, and the Hippa.
Speaker 4: Campus is actually really good at sort of bringing it
Speaker 4: all together right, not just when you're learning, but a
Speaker 4: lot of times when you're retrieving later on. And let's
Speaker 4: say a word to put you in the MRI scanner
Speaker 4: and ask you to bring back that memory. Hippi campus
Speaker 4: lights up like a Christmas tree, but other places in
Speaker 4: the brain light up as well. So it creates and
Speaker 4: holds onto this beautiful conjunction of where the bits and
Speaker 4: pieces of memory are stored, and it acts as kind
Speaker 4: of the thing that brings them together. We call it
Speaker 4: an index. It's the thing that kind of collects the
Speaker 4: bits and pieces of memory, so that particular memory would
Speaker 4: be stored pretty much throughout the brain. But the hippa
Speaker 4: campus is what brings the pieces together into one solid component.
Speaker 1: So I guess, let's say like the hippocampus is kind
Speaker 1: of a metal detector helping gather all that memory treasure
Speaker 1: on your beach. Also, I'm about to try to impress
Speaker 1: Mike by saying a lot of brain words. So a
Speaker 1: quick neuroanatomy lesson here. Now, a nerve cell or a
Speaker 1: neuron or a neuronal cell is, according to the National
Speaker 1: Institutes of Health, a type of cell that receives and
Speaker 1: sends message from the body to the brain and then
Speaker 1: back to the body, and messages are sent by a
Speaker 1: weak electrical current. Now, a nerve cell it looks kind
Speaker 1: of like a tree. It's got a long trunk in
Speaker 1: the middle and some branching, fingery things on one end.
Speaker 1: Those are aptly called dendrites because dendro means tree, and
Speaker 1: then the trunk part is called an axon, and where
Speaker 1: the roots would be are the axon terminals. And nerve
Speaker 1: cells receive signals on one end and then pass them
Speaker 1: to the next nerve cell, and so on and so forth,
Speaker 1: and that little gap between the two cells that they
Speaker 1: toss signal over is called the synapse. Now, surrounding all
Speaker 1: these nerve cells are glial cells, and those are brain
Speaker 1: cells that are not neurons, And there are a few
Speaker 1: different types of glial cells. We used to think that
Speaker 1: glial cells were just kind of like hung out near
Speaker 1: nerve cells, like wingmen, but it turns out that they
Speaker 1: can have a lot to do with how information gets processed,
Speaker 1: and they can affect synapses, and again different and types
Speaker 1: of glia. Microglia are the brains. Immune cells Macroglia like
Speaker 1: astrocytes help modulate the levels of neurotransmitters around those synapses.
Speaker 1: So let's hear me a podcaster try to just talk
Speaker 1: shop with someone who has spent decades studying the most
Speaker 1: complex aspect of our existence.
Speaker 3: And what about different types of neural cells? What about
Speaker 3: glial and microglial and neurons and dendroides. To science know
Speaker 3: yet what's firing off?
Speaker 4: We have a good inkling I think as to how
Speaker 4: memory could be instantiated in some of those structural features,
Speaker 4: but I should still say we still.
Speaker 2: Don't fully know. H I love that.
Speaker 4: So we have some ideas. We have some thoughts, and
Speaker 4: the ideas have been corroborated for many years now. And
Speaker 4: one particular facet is if you look at how memories
Speaker 4: can be stored at least, and if you were to
Speaker 4: create maybe a cellular form of memory, how can that
Speaker 4: be stored. It's the connections between brain cells, and not
Speaker 4: in the brain cells themselves necessarily. So the idea is
Speaker 4: that if you're a brain cell and you're talking to
Speaker 4: another brain cell, there's a certain strength of communication. So
Speaker 4: as one cell fire is what we call action potentials
Speaker 4: to communicate with the next cell. So that's the electrical
Speaker 4: firing that happens. That happens at a certain rate, and
Speaker 4: it's a certain level of communication. If the cells learn
Speaker 4: something new, you can change the strength of that connection.
Speaker 4: You can change the firing rates, you can change whether
Speaker 4: or not that cell is able to trigger the other
Speaker 4: cell that it's communicating with.
Speaker 1: So how strong that ability is to toss the signal
Speaker 1: from one axon terminal to be branching fingery dendrites of
Speaker 1: the next cell. Now, some cells, they might lob it
Speaker 1: softly with t rex arms, while other connected cells might
Speaker 1: deliver reliable fastballs, which would be TLP or long term potentiation.
Speaker 4: And that we've known about for quite some time. Since
Speaker 4: the seventies, we've suspected that the phenomenon called long term
Speaker 4: potentiation is a cellular form of memory. Now, since then
Speaker 4: we've uncovered a whole bunch of different other kinds of
Speaker 4: cellular type memories. But the problem is these are laboratory phenomena.
Speaker 4: So until you're able to record directly from a brain
Speaker 4: cell and another brain cell in a live behaving animal
Speaker 4: and see that change, which is very tricky because you
Speaker 4: don't know exactly where the action is going to be,
Speaker 4: you can guess as to you might put your electrodes
Speaker 4: in the hippa campus for example, But again, the hippocampus
Speaker 4: has you know, millions of cells, and you don't know
Speaker 4: which ones are going.
Speaker 2: To be the active ones.
Speaker 1: So those neurons, the ones with the dendrites on one end,
Speaker 1: the long trunky axon, and the little root like axon terminals.
Speaker 1: You have eighty six billion of those in your brain,
Speaker 1: and you'd have to be looking right at one as
Speaker 1: it changes with a memory. Now I crush them numbers.
Speaker 1: Let's say the average haystack is five feet by six
Speaker 1: feet and it weighs seventeen hundred pounds. So to find
Speaker 1: and look at the actual neuron sending and receiving signals
Speaker 1: when acquiring a memory, you would need to, in the
Speaker 1: blink of an eye, find a needle in forty seven
Speaker 1: thousand haystacks. It is difficult. Neuroscience turns out is hard.
Speaker 4: But so far the evidence all points to changes in
Speaker 4: synaptic strength or changes in the connections between cells. That's
Speaker 4: where memories seem to be stored. Now you brought up
Speaker 4: another really interesting point, which is what about other what
Speaker 4: we call non neuronal cells like glia or microglia, or astrocytes,
Speaker 4: or maybe things that are sort of outside of the
Speaker 4: cell or outside of synapses. And the answer is, oh,
Speaker 4: it gets complicated and it gets super interesting because we
Speaker 4: used to think that those cells are just there for support,
Speaker 4: and now we recognize that actually those cells do communicate
Speaker 4: and do play a really interesting and not very well
Speaker 4: understood role in some forms of communication across cells but
Speaker 4: also across each other. So the idea that glio sells
Speaker 4: for example, or glia have their own transmitters, have their
Speaker 4: own messengers, is one that is actively being studied now.
Speaker 4: So I think again we go back to how much
Speaker 4: doing in it? Well, it's a fraction of a fraction,
Speaker 4: maybe maybe five ten percent of what we stand to know.
Speaker 4: And when it comes to glia, we're nowhere near so
Speaker 4: we still have a lot more that we need to learn.
Speaker 3: And as long as we're talking five to ten percent,
Speaker 3: you want to just bust the myth right now that
Speaker 3: we only use ten percent of our brain.
Speaker 4: Yeah, let's go ahead, Okay, all right, So this is
Speaker 4: another one that you know, I sometimes will hear if
Speaker 4: I could just unlock a little bit more of my brain.
Speaker 4: Come on, you've got access. If you only had access
Speaker 4: to five to ten percent of your brain, guess what,
Speaker 4: only five to ten percent of your brain would actually survive.
Speaker 4: The rest of it would just afrophe.
Speaker 2: And go away. You're done with it, right, So.
Speaker 4: Brain cells need to be used constantly for them to
Speaker 4: be able to survive and thrive and do well. And
Speaker 4: I know this has been talked about in Hollywood. I
Speaker 4: was just rewatching Lucy the other day.
Speaker 2: THO it's a terrible movie.
Speaker 4: Yeah, I know, it was just on TV. It couldn't
Speaker 4: help it.
Speaker 5: It is estimated that most human beings only use ten
Speaker 5: percent of the brain's capacity. Imagine if we could access
Speaker 5: one hundred percent, interesting things begin to happen.
Speaker 4: There's a number of these, you know, Hollywood blockbusters out there,
Speaker 4: whether it's you know, you take a pill or some
Speaker 4: drug that like unlocks the full potential of the human brain.
Speaker 4: And I'm not saying that, you know, there aren't drugs
Speaker 4: that can improve function, optimize function, or give you a
Speaker 4: boost and all that, sure, but the idea that you're
Speaker 4: kind of stuck using five to ten percent and if
Speaker 4: you could just unlock like ninety percent, you'd be a
Speaker 4: superhuman entity.
Speaker 2: Or no.
Speaker 4: No, we use all of our brain all the time,
Speaker 4: and it really depends on what it is that we're
Speaker 4: doing at any given time. What that dynamic balance is
Speaker 4: and also all brain cells have kind of a basal
Speaker 4: level of firing of activity, and sometimes that's meaningful. Sometimes
Speaker 4: it's not meaningful. It's just kind of noise that sits there.
Speaker 4: But they have to be active in some respects, otherwise
Speaker 4: they wouldn't be useful.
Speaker 3: And you know, you said something about superhuman strength, but
Speaker 3: I know that there are some people whose memories are
Speaker 3: just bonkers super er what is it hyper.
Speaker 4: Highly superior autobiographical memory.
Speaker 3: The fact that that was on the tip of my
Speaker 3: tongue was just like putting in an MRI.
Speaker 2: Well, I'm glad you asked.
Speaker 4: So I happen to know something about those folks because
Speaker 4: we study them at ucer Vine and they were first
Speaker 4: identified actually by my colleague who's now an emeritus professor,
Speaker 4: Jim McGaw who built the center that I now currently direct.
Speaker 1: Ooh okay, bring it on, And just a quick primer,
Speaker 1: only about one hundred people on earth have been identified
Speaker 1: as having highly superior autobiographical memory, where they can vividly
Speaker 1: recall nearly every.
Speaker 3: Day of their lives.
Speaker 1: And this syndrome is also known as hyperthymesia, which means
Speaker 1: excessive remembering. It's just it's a lot there's a reason though,
Speaker 1: why people want to study them.
Speaker 2: So they're interesting.
Speaker 4: I don't know that I can tell you for sure
Speaker 4: whether or not their brains are all that different from
Speaker 4: yours and mind, but certainly their ability is different. So
Speaker 4: the first time that one of them was encountered by
Speaker 4: Jim McGaw, she was able to recall just an incredible
Speaker 4: level of detail from her childhood in teenage years. He
Speaker 4: was able to corroborate that to the extent possible using
Speaker 4: her diaries, and then went through an almanac and named
Speaker 4: off a whole bunch of different events, and she gave
Speaker 4: the exact dates. And one time she came up with
Speaker 4: something and it wasn't the right date from the almanac.
Speaker 4: Turns out she was right, the book was wrong. So
Speaker 4: it truly is incredible, and many have been identified since then.
Speaker 4: We've worked with a number of them to try to
Speaker 4: understand this incredible phenomenon. Now I should say I should
Speaker 4: backtrack a little bit and say why is this incredible?
Speaker 4: Why is it so difficult for a scientist to believe
Speaker 4: this is the case. And that's because for many, many decades,
Speaker 4: we believed that memory is highly fallible. It's not intended
Speaker 4: to be very accurate. It's intended to be kind of
Speaker 4: an estimation of reality. We forget things all the time,
Speaker 4: we make mistakes all the time, and that's all part
Speaker 4: of a healthy adaptive memory system. Because it never evolved
Speaker 4: to allow us to retain perfect records of the reality
Speaker 4: around us.
Speaker 1: We evolved to find Barry's and to work well with
Speaker 1: our peers, but maybe not to remember every lyric to
Speaker 1: obscure Lionel Richie songs or the password for your cable
Speaker 1: provider log in.
Speaker 4: And there were stories that were told. Alexander Luria, a
Speaker 4: famous psychologist, talked about one of his patients who had
Speaker 4: perfect recall. And you would think that this person would
Speaker 4: be very sort of well adjusted, but he wasn't. He
Speaker 4: had a difficult time with people around him in the
Speaker 4: social settings and so on. So it seemed like having
Speaker 4: this perfect memory was not desirable. It was almost as
Speaker 4: bad as having very poor memory was an extreme.
Speaker 1: So, according to the paper The Mind of a niem Honist,
Speaker 1: this subject in Alexander Luria's study was able to recall
Speaker 1: autobiographical information since one year of age. And the way
Speaker 1: in which he described his excellent memory was using a
Speaker 1: kind of grouping of the words like quote the distribution
Speaker 1: of houses in a street. But he also experienced a
Speaker 1: type of crossing of the senses, which we're going to
Speaker 1: get to later in this episode.
Speaker 4: And the first thought as a scientist as you go, Wow,
Speaker 4: that's unexpected. This shouldn't have happened, right, if we think
Speaker 4: about things in terms of evolutionary standards that have kind
Speaker 4: of got us to where we need to be because
Speaker 4: it promotes our survival, this should have never happened. There's
Speaker 4: no rationale, there's no reason why would this happen to somebody.
Speaker 4: And yet there they were, and they weren't maladjusted, they
Speaker 4: weren't not thriving. Some of them, obviously, there's variability that
Speaker 4: many of them were thriving and doing very very well.
Speaker 4: Many of the more celebrities, many of them hosted radio shows,
Speaker 4: did all sorts of things where they sort of leveraged it.
Speaker 4: They capitalized on this incredible memory. So this kind of
Speaker 4: took us down a little bit of a different path
Speaker 4: to say, well, wait a minute, maybe our understanding of
Speaker 4: what memory should do is not what it truly is.
Speaker 4: We always thought that it's supposed to be able to
Speaker 4: have an abstraction of reality but not be perfect. Will
Speaker 4: in situations where it's perfect. How do we make sense
Speaker 4: of that? Why is that the case? And we still
Speaker 4: don't know the answer. But they are one of the
Speaker 4: most interesting groups of individuals that we study. They're very
Speaker 4: generous with their time, and we're still kind of at
Speaker 4: the very beginning of trying to understand what that means
Speaker 4: for us.
Speaker 1: If you're like, wait, I have that, or my aunt
Speaker 1: is weird like that? You see Irvine Center for Neurobiology
Speaker 1: and Learning and Memory has this easy screening questionnaire. We'll
Speaker 1: link it on our website and they might want to
Speaker 1: talk to you. But again, it's really rare and also
Speaker 1: no cheating by looking at your calendar or your phone's
Speaker 1: camera role. I hate that I even have to say that. Also,
Speaker 1: don't be so quick to envy people with hyperthymesia. Studies
Speaker 1: show that they don't get to just ace like every
Speaker 1: trivia around or DMB tests they take. Their memories are
Speaker 1: usually strongest just in personal details of their lives. Now,
Speaker 1: in a minute, we'll get to all kinds of juicy
Speaker 1: gossip about your memory, but first, let's donate to a
Speaker 1: cause of theologists choosing and this week Mike asks that
Speaker 1: his donation as well as his honorarium, go to his
Speaker 1: labs fund to help graduate students, and this donation to
Speaker 1: the uc Orvine Center for the Neurobiology of Learning and
Speaker 1: Memory will help fund attendance at scientific conferences and seminars
Speaker 1: and support graduate student and postdoctoral training. Now find out
Speaker 1: more at the link in the show notes, and thank
Speaker 1: you to sponsors of this show for making that gift possible. Okay,
Speaker 1: back to the basics for this part one, and next
Speaker 1: week it will be all your questions, patrons. But let's
Speaker 1: chat about serotonin and dopamine and other brain sauces that
Speaker 1: keep us alive and remembering, and what.
Speaker 3: About the roles of neurotransmitters.
Speaker 4: So what happens to the average person if you're talking
Speaker 4: about the role of neurotransmitters and say memory storage. The
Speaker 4: way that we think about communication across brain cells is
Speaker 4: that the combination of electrical and chemical communication. The electrical
Speaker 4: communication is the action potential. That's the electrical signal that
Speaker 4: goes from the cell body all the way down what's
Speaker 4: called the axon. It's sort of long projection all the
Speaker 4: way down to the synapse.
Speaker 1: Okay, remember that's the dendrite, which has kind of the
Speaker 1: egg yolk looking cell guts, and then there's the trunk,
Speaker 1: the axon and the root looking things the axon terminal,
Speaker 1: and those toss that electrical signal to the next dendrites
Speaker 1: kind of like a daisy chain.
Speaker 4: But what it allows to happen in the synapse is
Speaker 4: the release of neurotransmitter. So that's where the chemical part
Speaker 4: of that communication is. And then the neurotransmitter binds, connects
Speaker 4: with receptors on the next cell, and triggers an action
Speaker 4: potential there, and you get the whole thing to propagate
Speaker 4: once more. So you have kind of electrical really fast chemical,
Speaker 4: a little bit slower, electrical again really fast, and so on.
Speaker 4: What happens when you have plasticity is the amount of
Speaker 4: neurotransmitter that is released can change, or the number of
Speaker 4: receptors that are able to bind that neurove transmitter on
Speaker 4: the receiving cells change.
Speaker 1: Now, neuro nerds know that there has been a big
Speaker 1: debate about which is the business end of a neuron,
Speaker 1: like the body that they control. Does a neuronal cell
Speaker 1: have its own head and butt? Some thought that the
Speaker 1: receiving end that rootball axon terminal is where the action
Speaker 1: is because the surface area of it allows for more
Speaker 1: neurotransmitter to bind it. They thought the axon terminal was
Speaker 1: at the wheel here, but other said that it's the
Speaker 1: Yoki cell guts on the dendrite or the dendrite branches
Speaker 1: themselves that are signaling the amount of neurotransmitter released. We
Speaker 1: need answers here.
Speaker 4: In reality, it turns out both happen, of course, and
Speaker 4: they're both different kinds of plasticity. One is presynaptic, one
Speaker 4: is postsynaptic, one is before, one is after, And it's
Speaker 4: not clear exactly when one happens versus the other, but
Speaker 4: both of those seem to be heavily involved, and both
Speaker 4: of those seem to lead to this kind of plasticity
Speaker 4: or what we call cellular memory.
Speaker 3: And what about the role of dopamine.
Speaker 1: For more on dopamine, you can see our ADHD episode
Speaker 1: with doctor Russell Barkley or the Fantastic Molecular Neurobiology episode
Speaker 1: with doctor Crystal Dilworth aka Doctor Brain.
Speaker 3: When it comes to attention and forgetting where things are
Speaker 3: or keeping track of time, things like that, does dopamine
Speaker 3: play a big role in that as well?
Speaker 4: It's really interesting you asked me this question now, because
Speaker 4: if you add if we did this a couple of
Speaker 4: years ago, I would have given you a very stereotypical
Speaker 4: answer as to the role of dopamine. Dopamine is what
Speaker 4: we call a neuromodulator. It is not necessarily the thing
Speaker 4: that makes memory happen, but it can improve the quality
Speaker 4: of memory storage. It can change that sort of context,
Speaker 4: especially if it's learning through reward, so like feedback driven learning,
Speaker 4: when you get an outcome says you did this right
Speaker 4: or you didn't do this right, so you kind of
Speaker 4: learn as a function of that feedback. Dopamine seems to
Speaker 4: be involved in that. A last couple years things changed
Speaker 4: a little bit. Dopamine started to become even more interesting.
Speaker 4: So in addition to the kinds of roles that we
Speaker 4: talked about, it seems to have this much more directed
Speaker 4: role also on the hippocampus and its ability to store memories.
Speaker 4: And it turns out that some types of memory seem
Speaker 4: to be dependent on dopamine rather than just modulated by dopamine.
Speaker 4: So you need to have dopamine there to be able
Speaker 4: to have that memory effectively stored and be functional. So
Speaker 4: I think we're again an example of how we're changing
Speaker 4: our knowledge. If you look at the textbooks, what is
Speaker 4: the role of dopamine, very stereotyped answer, You're very much
Speaker 4: linked to reward learning, feedback driven learning. But the data
Speaker 4: that's been accumulated since and is maybe not in the
Speaker 4: textbooks yet, is there's these additional roles for dopamine that
Speaker 4: are just now beginning to be understood.
Speaker 1: So dopamine is more than just a motivator. It can
Speaker 1: actually affect how memories are stored. So there's an ADHD link.
Speaker 1: But what about for people who also, let's just say,
Speaker 1: have anxiety. So the HPA access or the hypothermic to
Speaker 1: a Harry agreedal glands that is like a three part
Speaker 1: click of the endocrine system that fires away hormones like
Speaker 1: cortisol and adrenaline in fight or flight mode when you're
Speaker 1: scared of like a raccoon in the alley, or a date,
Speaker 1: or you're tardy for a dentist appointment and the receptionist
Speaker 1: is mean.
Speaker 3: And hormones the under system the HPA acts all that
Speaker 3: plays a role in neurotransmitters. Right, does that mean that
Speaker 3: hormones play a role in our memory a.
Speaker 4: Lot, absolutely, especially when you think about the HPA axis.
Speaker 4: When you think about say, hormones like cortisol and corticosteroids,
Speaker 4: which is the version that's released in the brain that
Speaker 4: does have a direct effect on memory, and it can
Speaker 4: change memory, and there's sort of an optimality can change
Speaker 4: it for the worse in the case of extreme stress,
Speaker 4: but it can also improve the quality when it's sort
Speaker 4: of an acute small level of stress. Because stress is
Speaker 4: one of those things where some of it is positive,
Speaker 4: too much of it is obviously very negative.
Speaker 1: For more on what's called you stress, we have a
Speaker 1: whole episode about happiness with doctor Lori Santos or huh.
Speaker 1: We have one on burnout with doctor Candy Ween's so
Speaker 1: good and bad stress your brain begs you to know
Speaker 1: the difference.
Speaker 4: So that's one that's pretty well known. There's a number
Speaker 4: of other hormones also that have an effect on memory storage,
Speaker 4: and we're still learning about how that impacts brain function
Speaker 4: and hippocampal function.
Speaker 2: Estrogen is one of them, uh huh.
Speaker 4: And we're learning a lot more now about how estrogen
Speaker 4: impacts the way that the hippo campus is able to
Speaker 4: store memories and of course, how that's different across the sexes,
Speaker 4: and also how it changes as a function of aging
Speaker 4: as we get older.
Speaker 3: The fact that estrogen isn't more studied in terms of
Speaker 3: brain function. I went through or varian failure really early
Speaker 3: in my thirties and didn't realize how much it was
Speaker 3: affecting my memory. I thought I was absolutely having early
Speaker 3: dementia because I would there are a few times I
Speaker 3: would write my address down wrong, or I would give
Speaker 3: someone information. I always could remember my hotel rooms when
Speaker 3: I would travel, and there were a few times before
Speaker 3: I got an estrogen therapy that I was like, what
Speaker 3: is my What is it? And I was like, oh, no,
Speaker 3: I'm losing my mind.
Speaker 2: Yeah.
Speaker 4: I mean, it's incredible how crucial it is to memory,
Speaker 4: and how drastic the impact of removing estrogen or changing
Speaker 4: estrogen function as a function of age menopause that has
Speaker 4: a real effect.
Speaker 2: And you're right, it.
Speaker 4: Is amazing that this is just now starting to become
Speaker 4: studied extensively. I think that there's a lot of positive
Speaker 4: things that have happened in the field recently that have
Speaker 4: led to that women's brain health initiatives, But for the
Speaker 4: longest time, we had a major problem in neuroscience and
Speaker 4: in biology in general, where most of the work in
Speaker 4: animal models, for example, was restricted to males hat and
Speaker 4: there was sort of this silly excuse of, well, males
Speaker 4: are just easier to deal with than we have a
Speaker 4: lot of complexity and female animals and refusing to deal
Speaker 4: with this complexity. But it's a very cheap excuse, right,
Speaker 4: And when you think about what we've learned since the
Speaker 4: nationalist Suites of Health mandating doing studies across both sexes,
Speaker 4: you start to elucinate all sorts of really interesting things
Speaker 4: about the biology of the system that you would have
Speaker 4: only learned when you start to study females and do
Speaker 4: it in a rigorous way. And it's also giving the
Speaker 4: illusion that males don't have very ability. Of course they do,
Speaker 4: and of course they have hormones, and of course they
Speaker 4: have very different levels that need to be studied as well.
Speaker 4: So this is about doing better science, more rigorous science broadly.
Speaker 1: In this matters because many studies have shown that women
Speaker 1: and people assigned female at birth are actually humans who exist.
Speaker 1: And let's also be honest, we're all freaked out about
Speaker 1: losing memory as we age, unless you think it would
Speaker 1: be cool, like every day is kind of a neat
Speaker 1: little surprise. Now does doc think hormones are a factor
Speaker 1: in that?
Speaker 4: So most of my work in the lab is with humans.
Speaker 4: When you think about postmenopause changes in estra's levels and
Speaker 4: hormone levels, most people tend to think of it as
Speaker 4: like a precipitous drop and it's acline. But even if
Speaker 4: you study people in their sixties and seventies, there are
Speaker 4: really interesting individual differences in levels of estrogen at that stage.
Speaker 4: And those differences in levels also are so with their
Speaker 4: memory function and associated with all sorts of things that
Speaker 4: are changing in their brains. So the nuance continues.
Speaker 2: To be there.
Speaker 4: And even just if you're curious about the science, really
Speaker 4: interesting findings.
Speaker 2: That are surfacing.
Speaker 3: Well, in the last three hundred thousand years, did we
Speaker 3: just not really evolve to be this old? Like? Where
Speaker 3: does memory and evolution play a part? And age? I mean,
Speaker 3: some people say that they can remember their birth. Other
Speaker 3: people are like, it was all a blur until I
Speaker 3: was like twelve, man, I don't know what happened. So evolutionarily,
Speaker 3: what's going on?
Speaker 4: Yeah, the evolution story of this actually is very interesting
Speaker 4: and it's one that may surprise you because we tend
Speaker 4: to think of memory always as a thing of the past,
Speaker 4: like we need to be able to remember. You just
Speaker 4: named a couple of examples, even remembering birth. Now, I
Speaker 4: don't know that anybody can actually remember that, but you know,
Speaker 4: certainly people claim to have very strong memories even from
Speaker 4: an early age. In reality, your brain systems are still
Speaker 4: wiring up during developments, so a lot of times those
Speaker 4: memories don't get held onto. There's a phenomenon called childhood amnesia,
Speaker 4: for example, where we know that those things are just
Speaker 4: not stored in the kind of high fidelity that you
Speaker 4: expect later memories to be stored in, and we forget
Speaker 4: a lot. Right, So why would evolution sort of wire
Speaker 4: or select for rather a system that is so fallible,
Speaker 4: that is so error prone. And the answer is a
Speaker 4: little bit maybe of a surprise, which is that memory
Speaker 4: never evolved to study and remember the past.
Speaker 3: Wait, so memory is not for thinking about the past. Huh.
Speaker 4: Memory did not evolve for us to be able to
Speaker 4: reminisce and tell stories and think about our past history.
Speaker 4: The only reason it evolved to be what it is
Speaker 4: today is to allow us to make decisions that are
Speaker 4: better for us in the future. So it's all about survival.
Speaker 4: And if you think about it from that context of
Speaker 4: this system has been wired over generations and generations to
Speaker 4: maximize our ability to use past experience to inform future decisions.
Speaker 4: So we can promote our survival, you become a lot
Speaker 4: more tolerant of errors. It's okay because I don't need
Speaker 4: to have a perfect recall of the past. I just
Speaker 4: need to know that bears are bad, or this is
Speaker 4: a poisonous berry bush, or those kinds of things, right,
Speaker 4: and I also need to know about the positives. Some
Speaker 4: things are going to be rewarding. Some experiences I want
Speaker 4: to have again and again because they were very rewarding
Speaker 4: in the past.
Speaker 1: Likewise, your past is only there to guide your future.
Speaker 1: You can, but you are not obligated to dwell on
Speaker 1: the past and carry it like an ox haul in
Speaker 1: a wagon of sad nostalgia.
Speaker 4: So that's what sort of motivates our memory systems, right,
Speaker 4: being able to use that past experience, generalize and extract
Speaker 4: knowledge from those experiences things that you can apply to
Speaker 4: be able to make better decisions in the future. Not
Speaker 4: about reminiscing, not about storytelling, However, there's a caveat to this.
Speaker 4: As a species, humans are very social and we love
Speaker 4: to tell stories. I will not dismiss the possibility that
Speaker 4: perhaps a side effect of this evolution of memory and
Speaker 4: the telling stories does have a social bonding value, and
Speaker 4: that in and of itself also promotes at least a
Speaker 4: group survival and at the individual level. Probably also because
Speaker 4: we know that one of the best things you can
Speaker 4: do for yourself as you get older is maintain some
Speaker 4: social structures and be social around others. That seems to
Speaker 4: be protective almost as much as physical activity for example.
Speaker 1: Okay, so for making better decisions and telling jokes and
Speaker 1: having a kiki.
Speaker 3: What about age? When do you find people are able
Speaker 3: to recall some of their first memories.
Speaker 4: Typically, so if we're excluding people who have this highly
Speaker 4: superior autobiographical memory where it's like every day, and even
Speaker 4: then it starts in their teenage years, typically you have
Speaker 4: periods in your life where you have better memories for
Speaker 4: events that happen, and then periods of your life that
Speaker 4: feel like it was a blur. Let's say you talk
Speaker 4: to someone in there mid forties, they might be able
Speaker 4: to identify a handful of experiences from their childhood or
Speaker 4: teenage years that are very vivid that they recollect very well.
Speaker 4: Turns out it may not be entirely their recollection. It
Speaker 4: may be the stories they heard about it from other
Speaker 4: family members and so on. So it's like some version
Speaker 4: of that reality, but it's not exactly the same thing
Speaker 4: as what actually happens. But if you ask them about
Speaker 4: other times in their life where there may have been
Speaker 4: specific things that are happening that are very very vivid,
Speaker 4: maybe if it was the birth of a child, or
Speaker 4: receiving a big award, or the death of a family member,
Speaker 4: something very positive or very negative, something very emotional, they
Speaker 4: might have a lot of memories around that time that
Speaker 4: come back with a lot of clarity. They might call
Speaker 4: them you know, I feel like this was just yesterday,
Speaker 4: and when they bring them back, they bring them with
Speaker 4: a lot of emotion. They're sort of reliving the experience.
Speaker 4: And we probably have a handful of those experiences in
Speaker 4: our past history, whether it was you know, something that
Speaker 4: happened to you or to your family member, or something
Speaker 4: that happened around us, some crisis or an attack, or
Speaker 4: something that is very sim the natural disaster, something very salient.
Speaker 1: Once during a series of earthquakes, I hid under a
Speaker 1: table for two days and my mom would come and
Speaker 1: bring me hot dogs.
Speaker 4: Those memories typically are very, very strong and long lasting.
Speaker 4: But if you were to track, for example, my memory
Speaker 4: for events that happened in my life, I have a
Speaker 4: lot of black holes. There are lots of periods where
Speaker 4: I just don't have the greatest recollection.
Speaker 2: But if somebody were to ask.
Speaker 4: Me about it and remind me and tell me stories
Speaker 4: about it, I can piece it back together.
Speaker 3: What's that all about?
Speaker 4: So this is the tension between QWED recall versus free recall.
Speaker 4: If there's a queue, if I see a picture, if
Speaker 4: I see a name and that reminds me of something,
Speaker 4: I can bring that back with relative ease, and that
Speaker 4: tells me it's been stored. It's somewhere in my brain.
Speaker 4: But I needed to find the right queue to be
Speaker 4: able to bring it back. And I think that's a
Speaker 4: general experience that a qeued recall of the past is
Speaker 4: much easier to trigger than just asking somebody to freely recall.
Speaker 4: When they freely recall, you'll identify very quickly those black
Speaker 4: holes in their history.
Speaker 3: You know, you mentioned the birth of a which I
Speaker 3: was just talking to my mother in law about this
Speaker 3: the other day, about the amnesia that happens when you
Speaker 3: give birth. I have not had children, but from what
Speaker 3: I understand I have heard, that's like you immediately forget
Speaker 3: that that was the most excruciating pain a human being
Speaker 3: can feel, and then you're like, let's do this again
Speaker 3: and have more babies. I imagine if that is true,
Speaker 3: there's definitely an evolutionary purpose for that. But is there
Speaker 3: something hormonal that just says don't worry about it?
Speaker 4: There must be There must be some by a lot.
Speaker 4: I mean, I've heard the same exact thing. I can
Speaker 4: attest this is to be true. You can ask my
Speaker 4: wife the same exact thing, and yeah, it's like, are
Speaker 4: you forgetting how how painful that whole thing was? Now
Speaker 4: let's do it again? And you're right, there is something
Speaker 4: to that.
Speaker 1: And according to the papers Memory for Labor Pain, a
Speaker 1: review of literature, labor pain intensity is remembered accurately or
Speaker 1: decreases on recall, and researchers have suggested that the recall
Speaker 1: of childbirth, including recall of its pain, maybe subject to
Speaker 1: what's called the halo effect. Since recall of negative aspects
Speaker 1: of childbirth, including severe pain, is incompatible with a positive
Speaker 1: experience of having a baby. Memories are positively affected, at
Speaker 1: least in the short term, and that this hypothesis would
Speaker 1: predict that recall of pain would be reduced. So this
Speaker 1: is called the halo effect. But it's a little more
Speaker 1: than just forgetting how much it hurt. It's not so
Speaker 1: much that the memory of the pain just evaporates, but
Speaker 1: it's that it's eclipsed, hopefully by the relief of having
Speaker 1: gone through it and if all goes well, having a
Speaker 1: new creature exists, plus the boost of knowing that you
Speaker 1: coped and that you got through it. But some of
Speaker 1: those early days also can just be a little hazy.
Speaker 4: Now we have to also not discount the fact that
Speaker 4: right after birth there's a period of sleep deprivation. There's
Speaker 4: a period of you're sort of walking around really like
Speaker 4: a cognitively impaired patients for some time because of the
Speaker 4: sleep loss, that changing rhythms, that constantly having to feed
Speaker 4: another human being.
Speaker 2: You know, all of those things.
Speaker 4: Are very very difficult for the body to be able
Speaker 4: to adapt to and very difficult for the brain people
Speaker 4: adapt to. So whether or not what you're experiencing during
Speaker 4: that period of time ends up being sort of not tracked, right,
Speaker 4: because our machinery that allows us to learn and encode
Speaker 4: and remember things is disrupted a bit. That may be
Speaker 4: the case. That may be a contributor to it, but
Speaker 4: I don't discount the possibility. Again, what you said is
Speaker 4: very interesting. Maybe there's an evolutionary reason for this amnesia,
Speaker 4: especially surrounding perhaps the pain of the experience, and if
Speaker 4: some have had maybe a challenging pregnancy, they could perhaps
Speaker 4: forget about that and we'll still want to do it again. Yeah,
Speaker 4: there's a good survival evolutionary argument to be made around that.
Speaker 4: But I tend to make too many evolutionary arguments and
Speaker 4: I can't ever substantiate them because we don't really know, right,
Speaker 4: So there's always the we have no idea it could
Speaker 4: have evolved this way.
Speaker 2: Totally makes sense. It's just kind of a just so story.
Speaker 1: But if you are listening in your screen, I forgot nothing.
Speaker 1: We see you too. So. A twenty twenty study in
Speaker 1: the Journal of Anxiety Disorders Hey titled Traumatic Memories of
Speaker 1: Childbirth Relate to Maternal postpartum post traumatic stress Disorder, found
Speaker 1: that after labor. Some new birthing parents experience what's called
Speaker 1: cb PTSD or childbirth post traumatic stress disorder, and they
Speaker 1: had muddier memories of the events of labor, but they
Speaker 1: also experienced more emotional and sensory details and had more
Speaker 1: involuntary flashbacks of it, and their childbirth experience was also
Speaker 1: a greater factor in their identity. And there was a
Speaker 1: twenty twenty three study titled Relationship between Birth Memories and
Speaker 1: Recall and Perception of Traumatic Birth in Women in the
Speaker 1: postpartum one year period and Affecting Factors, and that used
Speaker 1: data collected with something called the Birth Memories and Recall
Speaker 1: Questionnaire and Perception of Traumatic Childbirth Scale to find that
Speaker 1: nearly half of all the study participants who gave birth
Speaker 1: perceived the experience as traumatic, nearly half trauma. However, it
Speaker 1: offers that more birthing education before labor and support from
Speaker 1: medical personnel during and after labor can lessen the perception
Speaker 1: and the memory of the trauma. Do we know anything
Speaker 1: about I mean, speaking of traumatic experiences, do we have
Speaker 1: any idea why some things that are really negatively impactful,
Speaker 1: like remembering where you were if you were alive when
Speaker 1: the towers were hit, or the moment that you heard
Speaker 1: COVID was a thing and that we were going into lockdown,
Speaker 1: or the insurrection of the United States Capital, or that
Speaker 1: Betty White died.
Speaker 3: My mom used to talk about when she heard JFK
Speaker 3: was shot, where she was standing and what she was
Speaker 3: wearing versus you know, with some childhood trauma, people have
Speaker 3: maybe subconscious recollections, but nothing that they can piece together.
Speaker 3: Why do big events like that have different storage.
Speaker 4: We talked about this a little bit when we talked
Speaker 4: about flash belt memories, right, and a lot of times
Speaker 4: those can be related to your own experiences. Something very emotional,
Speaker 4: very salient, very consequential, deeply impacted or maybe threatened your survival.
Speaker 4: Those kinds of things were going to have some vivid
Speaker 4: recollections about that. I still remember very vividly when the
Speaker 4: twin towers got hit, and the memories of that come
Speaker 4: back very quickly, and the emotion with that comes back
Speaker 4: very very quickly. And the same thing, you know, when
Speaker 4: people talk about the JFK assassination, when they talk about
Speaker 4: other events that have happened, they say, I remember exactly
Speaker 4: where I was, I remember the conversation, I remember what
Speaker 4: I was wearing to this extreme level of detail, but
Speaker 4: there's a caveat. So psychologists used to always think of
Speaker 4: those as Flashbult memories. These are incredibly detailed kinds of recollections,
Speaker 4: and no one ever questioned their veracity, no one ever
Speaker 4: questioned whether they're actually accurate till people did the studies.
Speaker 4: And you determine very quickly when you look at this
Speaker 4: body of literature, looking at flash Beld memories, you an
Speaker 4: example in a second that even though the confidence in
Speaker 4: those memories is extremely high, and the emotional context is
Speaker 4: extremely high, the actual accuracy of the details sometimes can
Speaker 4: be quite low. What which was a surprise for a
Speaker 4: lot of people to hear, And I'll give you example.
Speaker 4: This was a study I think from the early two
Speaker 4: thousands by colleague down in San Diego, Larry Squire. He
Speaker 4: looked at Now, granted, this is not as traumatic as
Speaker 4: some of the things that we talked about, but it
Speaker 4: was still a big news making event, and it was
Speaker 4: the verdict in the OJ Simpson case.
Speaker 1: October third, nineteen ninety five, a former football player and actor,
Speaker 1: was acquitted of killing his ex wife, Nicole Brown Simpson
Speaker 1: and her friend Ronald Goldman, and you may not have
Speaker 1: been born yet, but every TV seemed tuned to it.
Speaker 1: I was learning about plants in a classroom at the time,
Speaker 1: and yeah, my teacher had had the TV on for it.
Speaker 4: And they asked people questions. These were college undergraduates, questions
Speaker 4: about out this event, things like where were you at
Speaker 4: the time, what did you hear, how did you hear it,
Speaker 4: what was the context? And then ask them again after
Speaker 4: a few months, and then ask them again after a year,
Speaker 4: and they determined again very quickly that initially, when you
Speaker 4: ask you get a lot of accurate details and very
Speaker 4: few sort of distortions or what we call illusory details.
Speaker 1: Illusory implies this false impression based on a faulty observation
Speaker 1: or one that's influenced by emotions.
Speaker 4: But as you wait a while and you ask that
Speaker 4: question again, you find that things flip and actually the
Speaker 4: majority of the details that are brought back are now
Speaker 4: illusions or distortions, and the number of accurate things is
Speaker 4: actually quite low. And this is consistent with what we
Speaker 4: know to be true and the false memory literature. Another
Speaker 4: colleague here, bethloftis made a career of studying false memories.
Speaker 4: She's really one of the biggest pioneers in this area,
Speaker 4: and she's always quick to point out how fallible our
Speaker 4: memory systems are, and just because something is highly emotional
Speaker 4: or highly traumatic does not automatically mean it's going to
Speaker 4: be stored with high fidelity. We tend to have a
Speaker 4: bit of a contrast that happens when a traumatic event
Speaker 4: is happening to us. We focus on particular central features
Speaker 4: of that event that are really important for our survival.
Speaker 4: If somebody has held at gunpoint, for example, they might
Speaker 4: recall that gun, where it was pointing, the color details
Speaker 4: about that, but they may very very quickly forget what
Speaker 4: the assailant was wearing, or in some cases, the race
Speaker 4: of the assailants, and it leads to all sorts of
Speaker 4: false eyewitness testimonies. It leads to a lot of these
Speaker 4: illusory memories or memory distortions that surface. And she's very
Speaker 4: good at demonstrating this in laboratory studies, so you can
Speaker 4: demonstrate very quickly that eyewitness testimony is subject to all
Speaker 4: sorts of leading questions that can change the way that
Speaker 4: these memories are stored in the brain. You can quickly
Speaker 4: implant false memories into people's brains just by give them
Speaker 4: these false narratives and then they incorporate it. And none
Speaker 4: of this is lie or malice. By the way, this
Speaker 4: is actually changing the stored memories.
Speaker 3: Now, this work is very, very, very tricky.
Speaker 1: And this neuroscientist Beth Loftis has come up against a
Speaker 1: lot of criticism, even death threats, for research and data
Speaker 1: about how traumatic memories are stored and how evidence based
Speaker 1: on witness testimony can be flawed, which has led to
Speaker 1: the acquittal or exoneration of some alleged perpetrators of crime.
Speaker 1: So debatable memory is in fact very debatable, and people
Speaker 1: do debate it. And the difficult part about all of
Speaker 1: this is that there's so much we don't yet know
Speaker 1: about how the brain works. And I was thinking about this,
Speaker 1: and in my twenties, I was held a bit knife
Speaker 1: point and I was too frozen to scream. It was
Speaker 1: one of those it was like a dream where you
Speaker 1: can't even make a noise, but I was still able
Speaker 1: to memorize the license plate of the ghetaway car. And
Speaker 1: then the detective came to my house and showed me
Speaker 1: photos to id the suspect, and I was like, that's
Speaker 1: the guy, And I picked a guy who had a
Speaker 1: strong alibi and was not there. But the guys who
Speaker 1: stole my stuff ended up using my cell phone to
Speaker 1: call their girlfriends, so they got arrested, and I felt
Speaker 1: bad because they were juveniles, are like seventeen, and I
Speaker 1: think about that mugging all the time, and I feel
Speaker 1: like I still remember so many details really clearly, but
Speaker 1: I wonder how many have warped by now, which is terrifying.
Speaker 1: But I think about those two kids a lot and
Speaker 1: just what they're doing now and how they're doing. I
Speaker 1: bet they don't remember me, and that's fine.
Speaker 4: And that goes back to teach us something very important
Speaker 4: about memory, which is that it's very dynamic. It's not static,
Speaker 4: it's not always the same. It is constantly dynamic and
Speaker 4: malleable and changing. And anytime that I hear something that's
Speaker 4: related to something that I already know, what I already
Speaker 4: know changes a little bit to accommodate this new thing
Speaker 4: that I just heard. So our memories are constantly being corrupted.
Speaker 4: Anytime that I tell you about something from my childhood,
Speaker 4: you're going to get maybe like thirty percent accurate details,
Speaker 4: and the rest of it is just fiction.
Speaker 3: How do we trusty.
Speaker 4: Yeah, that's a challenge. I think that it starts to
Speaker 4: really question the value of the stories and the value
Speaker 4: of reminiscing, the value of being able to tell. The
Speaker 4: key thing to remember is, again, this is not what
Speaker 4: memory has evolved for. You still have the social thing
Speaker 4: when you tell stories, even if they're not true. You
Speaker 4: can still bond. You can tell very interesting stories, very
Speaker 4: interesting narratives. But the key thing to remember is that
Speaker 4: despite the fact that the details you remember may be different,
Speaker 4: your memory system and your brain have extracted whatever knowledge
Speaker 4: was necessary to be able to promote your survival successfully
Speaker 4: because that's what it evolved to do.
Speaker 2: That's what it got wired to do.
Speaker 4: It'll still do that regardless of what details you remember,
Speaker 4: what details you're able to tell in the stories.
Speaker 3: What about memories that we don't remember by design? Do
Speaker 3: we remember things subconsciously like do we remember, say, childhood
Speaker 3: traumas or things like that that are subconscious that we
Speaker 3: consciously don't want to pull up an envision.
Speaker 4: The idea of an unconscious memory that's stored that is
Speaker 4: very difficult to have come to the surface has been
Speaker 4: talked about by psychologists and philosophers for a long time.
Speaker 4: We talk about repressed memories. I mean, you can get
Speaker 4: Freudian with this, right, But even if you look at
Speaker 4: whether or not this phenomenon happens, one hundred percent, it happens.
Speaker 2: It's real.
Speaker 4: You can see it in the clinic, you can see
Speaker 4: it as you talk to people, and there are ways
Speaker 4: to be able to get that information to come out.
Speaker 4: The psychologist's perspective would tell you that these memories may
Speaker 4: be so traumatic, so difficult to deal with, that having
Speaker 4: them come to the surface would essentially incapacitate the person
Speaker 4: so much that it's a survival tool to be able
Speaker 4: to store it in a way where it is not
Speaker 4: directly accessible. Now, that's very uncomfortable talk to a neuroscientist, right,
Speaker 4: So every time that I've heard that, I sort of
Speaker 4: cringe a little bit and go, I don't know what
Speaker 4: mechanism that would be, right, And I still don't know
Speaker 4: the answer. So the unfortunate answer that I can give you,
Speaker 4: I guess is I don't think this is very tractable
Speaker 4: for a neuroscientist to study. Now, certainly there are things
Speaker 4: that are beyond our consciousness that can impact behavior, and
Speaker 4: we can do that in the laboratory right. We can
Speaker 4: have a memory that is sort of taught to you
Speaker 4: over time in a laboratory setting that unconsciously changes how
Speaker 4: you behave in a certain task.
Speaker 2: That's easy to do.
Speaker 4: But that's different from repressed memories and trauma and those
Speaker 4: kinds of things. That's very difficult to study in a
Speaker 4: laboratory setting. So I have to sit with that discomfort
Speaker 4: for some time. But unfortunately the psychologists may be the
Speaker 4: only ones with some sort of answer for this one
Speaker 4: at this time.
Speaker 3: You know, you mentioned different senses helping you store a memory.
Speaker 3: The more senses maybe that are involved, perhaps the more
Speaker 3: vivid it becomes. Yes, but where does something like synesthesia
Speaker 3: play a role where you maybe have different colors for dates,
Speaker 3: or different emotions for sounds things like that.
Speaker 2: Yes, so great.
Speaker 4: You started with the definition of synesthesia, and that's an
Speaker 4: important one to think about, right, is that it's a
Speaker 4: form of sensory crossing. Things that normally should be seen
Speaker 4: and visualized may be heard, and things that you know,
Speaker 4: maybe heard may have a certain color to them. And
Speaker 4: we hear these stories all the time. So the way
Speaker 4: that we used to think about our senses is that
Speaker 4: they operate in parallel and they're totally different from each other. However,
Speaker 4: you recognize, oh, actually, our sensory modalities cross all the time,
Speaker 4: and they talk to each other all the time, and
Speaker 4: they connect with each.
Speaker 2: Other all the time.
Speaker 4: So a great example that I think vs Rama Chandron
Speaker 4: does this example sometimes in his talks.
Speaker 2: One of them is kiki, one of them is.
Speaker 4: Buba, where he'll draw two things on the screen, one
Speaker 4: little figure with very very sharp edges and one with
Speaker 4: very soft rounded edges. Which one is kiki and which
Speaker 4: one is How many of you think that's kiki and
Speaker 4: that's buba? And he'll say, if I tell you that
Speaker 4: one of these is called kiki and the other one
Speaker 4: is called buba, which one is kiki, which one is buba?
Speaker 2: Yeah, of course, it's very simple.
Speaker 4: Everyone says the rounded edge version is buba, the sharp
Speaker 4: edged version is kiki. And he would say, well, that
Speaker 4: tells you that you have a little bit of synesthesia.
Speaker 4: There's no reason why you might link the name with
Speaker 4: the shape this way unless there was some form of
Speaker 4: sensory crossing. So all of us have a little bit
Speaker 4: of that crossing. However, in documented cases of actual sensory
Speaker 4: crossing that is much more dramatic where let's say you're
Speaker 4: playing the piano and you hit a certain note and
Speaker 4: you see a certain color, maybe a warm red or
Speaker 4: something like that. That is a sort of a formal
Speaker 4: way to be able to look at that crossing in
Speaker 4: many cases elicits creativity and it leads to a very
Speaker 4: interesting experience of the real world around you. Instead of
Speaker 4: having to kind of work at creating multimodal traces of
Speaker 4: the world, now everything seems to also be multimodal for you,
Speaker 4: so when learning might be a little bit easier, you
Speaker 4: get some sorts of interesting talent that arises from that.
Speaker 4: But I will go back to one case that I mentioned,
Speaker 4: and that was Alexandre Luria's patients who have this perfect recall.
Speaker 4: What I did I didn't mention to you, is that
Speaker 4: particular patients he called him patients s also had an
Speaker 4: extreme form of multisensory synesthesia.
Speaker 1: So again having a sense linked to another sense, like
Speaker 1: associating flavors for different words. And apparently Charlie XCX has
Speaker 1: synesthesia and has said I see music in colors. I
Speaker 1: love music that's black, pink, purple, or red, but I
Speaker 1: hate music that's green, yellow, or brown. She says, Wait,
Speaker 1: so she hates green music that's like her brand. So
Speaker 1: I looked into this, and she told Vogue magazine that
Speaker 1: she chose that neon lime shade for her album art
Speaker 1: for Brat because, quote, I wanted to go with an offensive,
Speaker 1: off trend shade of green to trigger the idea of
Speaker 1: something being wrong, she shared. Now me, your internet, dad,
Speaker 1: I have synesthesia, and for a long time I didn't
Speaker 1: know that it was weird for different years to be
Speaker 1: different colors or numbers, to have personality, or songs to
Speaker 1: have different shades to them. And my friend Micah, who
Speaker 1: I'm about to mention again, Hi. Mikah says that when
Speaker 1: he's mixing music, he's a musician. Sharp notes taste like
Speaker 1: metal to him. All of this without the expense of hallucinogens.
Speaker 4: And it's impossible to be able to reproduce what that
Speaker 4: experience is like for someone who doesn't have it. I
Speaker 4: can't possibly know what that experience of the external world
Speaker 4: is because I can only tell based on whatever it
Speaker 4: is that they describe. Now, in his case, that seemed
Speaker 4: to help be able to have this perfect recall and
Speaker 4: be able to retain things with a very, very high fidelity.
Speaker 4: But again, he was not a very well adjusted person.
Speaker 4: He struggled in social settings, struggled to maintain a job,
Speaker 4: and all of those kinds of things. So a little
Speaker 4: bit of synesthesia seems to work well, one or two
Speaker 4: senses being crossed for creativity seems to work well. But
Speaker 4: a dramatic sort of you know, five way synesthesia, which
Speaker 4: is what he had, that seems to be quite devastating.
Speaker 3: Do neumiologists ever look to people who have either lost
Speaker 3: their sight or never had it, or people who are
Speaker 3: hard of hearing or deaf too, or my friend Micah
Speaker 3: I've talked about him. Sorry, Micah lost his sense of
Speaker 3: smell as a baby when he had a fever. And
Speaker 3: how maybe that lack of input from one sense changes
Speaker 3: the way we remember.
Speaker 4: Things absolutely, And it goes back to the concept of plasticity.
Speaker 4: And we talked about this a little bit in the
Speaker 4: context of learning new things, but when it happens developmentally also,
Speaker 4: there's a massive capacity for rewiring. So when you look
Speaker 4: at individuals with congenital forms of blindness, let's say that
Speaker 4: now they're an adult, and you put them in an
Speaker 4: MRI scanner, and now you're giving them an auditory stimulus,
Speaker 4: so this is an experience that they're hearing, they're listening.
Speaker 4: What you find in some cases is activity in their
Speaker 4: visual cortex.
Speaker 1: So areas of the brain associated with vision go off
Speaker 1: in a person who's blind, which is.
Speaker 4: Really interesting because suggests that this part of the brain
Speaker 4: has not been getting the appropriate input since birth, but
Speaker 4: it has adapted and become plastic to respond to input
Speaker 4: from other senses. And some have suggested that that might
Speaker 4: allow those senses to become much more sharply tuned and
Speaker 4: sort of much more accurate. And I'm not saying that,
Speaker 4: you know, for some humans you have like bat like
Speaker 4: echolocation and so on, but that has been claimed in
Speaker 4: some cases of those with congenital blindnesses that you get
Speaker 4: this increased sharpness of their other senses. But there is
Speaker 4: something to be said for use it or lose it.
Speaker 4: The cortex is there, and if the cortex can start
Speaker 4: to listen to other senses that are coming in and
Speaker 4: wire appropriately, it's going to try to be useful for that.
Speaker 3: Is that sort of like using resources or real estate
Speaker 3: that you wouldn't otherwise be using or is that so
Speaker 3: off of an analogy.
Speaker 4: No, I think that's a great analogy. I mean, we
Speaker 4: talk about resources in real estate all the time because
Speaker 4: the cortex. I have a colleague here who has studied
Speaker 4: the cortex in brains of animals for a long time,
Speaker 4: and he makes the claim, and I agree with this
Speaker 4: claim that cortex is cortex throughout, and the same stuff
Speaker 4: that makes your visual cortex also makes your auditory cortex
Speaker 4: and also makes other sensory courtesies, so one can sort
Speaker 4: of fill in for the other. The difference is, of course,
Speaker 4: the reason why they're all different from each other is
Speaker 4: by virtue of the inputs, the things that are coming in.
Speaker 4: But if that's changed, if that's altered, and they can
Speaker 4: sort of adapt and listen to other input then they
Speaker 4: can be useful. And that's just using more resources more
Speaker 4: real estate. In some ways, you can think of the
Speaker 4: brain as a very primitive object here, right. It's going
Speaker 4: to use whatever it has access to, whatever it can
Speaker 4: to be able to solve challenges, to be able to
Speaker 4: address questions and allow the organism to survive to the
Speaker 4: best of its ability. And if one way to do
Speaker 4: that is by rewiring and listening to a different form
Speaker 4: of input, why not.
Speaker 3: I have questions from listeners, Can I ask you one million?
Speaker 1: Of course yes, so ask neuroscientists your neurotic questions. If
Speaker 1: you're me and who boy?
Speaker 3: Howiday?
Speaker 1: Next week? Do we have a great part two with
Speaker 1: all your questions on how to remember names and faces,
Speaker 1: what causes dementia, photographic memories, amnesia, short term memory, memory,
Speaker 1: and executive function so much more so, thank you to
Speaker 1: doctor Michael Yassa and everyone done on IRVI. I'm for
Speaker 1: helping arrange this. More links to the lab and his
Speaker 1: work are in the show notes and up on our
Speaker 1: website at aliwar dot com, slash ologies, slash ne monology.
Speaker 1: We are at Ologies on Instagram and now Blue Sky,
Speaker 1: where it seems to everyone is headed hop in Water's warm,
Speaker 1: Sky's Blue. Also hello to everyone listening on Spotify. I
Speaker 1: love to see your yearly wrapped lists and your comments
Speaker 1: for every episode. Smologies are shorter, kid friendly episodes that
Speaker 1: you can find anywhere you get podcasts. Just look for
Speaker 1: the new green artwork by Portland artists Bonnie Dutch who
Speaker 1: for the holidays or any occasion, Bonnie Dutch can make
Speaker 1: you a wonderful custom pet portrait or other commission. B
Speaker 1: o Ni Dutch, You can find her. Thank you to
Speaker 1: Aaron Talbert for admitting the ologies podcast Facebook group. Ablely
Speaker 1: Malick makes our professional transcripts. Kelly ar Dwyer does the website.
Speaker 1: Noel Dilworth is our scheduling producer. Susan Hale managing directs
Speaker 1: it All, Jake Chafy edits and lead editor. And another
Speaker 1: great brain is Mercedes Maitland of Maitland Audio, with some
Speaker 1: assists from Jarrett Sleeper of mind Jam Media. When I
Speaker 1: am late on things that Mercedes and Jake have to
Speaker 1: go to bed, I'm so sorry. I'm a little down
Speaker 1: to the wire because of the holidays, but everyone's wonderful
Speaker 1: and thank you so much. Nick Thorburn wrote the theme music.
Speaker 1: And if you stick around to the end of the episode,
Speaker 1: I tell you a secret. And this week is that
Speaker 1: I have an audiobook mixtape in the works, and I
Speaker 1: wanted to have it up by Thanksgiving here in America,
Speaker 1: but I chilled too hard on a farm for a
Speaker 1: few days for over the holiday, and we played this
Speaker 1: game that my friend Katherine Burns. She is two time
Speaker 1: Emmy Award winning choreographer Katherine Burns, who I've known for decades,
Speaker 1: so she her favorite game to play is Catchphrase Janga
Speaker 1: that she invented where you play catchphrase, which is this
Speaker 1: little game that you can purchase. It looks like a
Speaker 1: frisbee with a little screen and it gives you phrases
Speaker 1: that you have to gather people to guess. You can
Speaker 1: also get it an app like it on your phone.
Speaker 1: So whoever is left holding the catchphrase when the timer
Speaker 1: goes off then has to withdraw a jungle block. So
Speaker 1: it's just catchphrase, but instead of points, you just have
Speaker 1: to do jenka. Honestly, the stakes the phrase guessing. It's
Speaker 1: a thrill. What a way to pass several hours at
Speaker 1: a time. I love it catchphrase Jenka, Get into it. Also,
Speaker 1: that audiobook mixtape will be up in like a day
Speaker 1: or two. Sorry, great books from somologists authors. It's like
Speaker 1: a scholastic catalog in your ears. But next week more
Speaker 1: Memory Part two. It's so good, Okay, bye.
Speaker 3: Bye pacadermatology, bombiology, cryptozoology, lithology, zechinology, meteorology, fritology, nathology, seriology, elithology.
Speaker 5: Then real is simply electrical signals interpreted by your brain.