Speaker 1: My Welcome to Stuff to Blow Your Mind, a production
Speaker 1: of I Heart Radios How Stuff Works. Hey, welcome to
Speaker 1: Stuff to Blow Your Mind. My name is Robert Lamb
Speaker 1: and I'm Joe McCormick, and we're back with part two
Speaker 1: of our exploration of planarians, memory, learning and conditioning, and
Speaker 1: of course today we're going to get to the cannibalism.
Speaker 1: That's right. If you did not listen to part one,
Speaker 1: do go back and listen to it, because we lay
Speaker 1: the groundwork. We discussed these organisms, why they're interesting. We
Speaker 1: discussed their regenerative powers. We talk about McConnell himself. We
Speaker 1: talk about his personal and professional history as well as
Speaker 1: his run in with the unit Bomber. Right. Uh, so
Speaker 1: that figure, of course is James V. McConnell, the American psychologist.
Speaker 1: But if you listen to the last episode, as you
Speaker 1: should before this one, you already know that. So we're
Speaker 1: picking up after McConnell's initial research demonstrating in the nineteen
Speaker 1: fifties that despite conventional wisdom that in vertebrates could not learn,
Speaker 1: could not be trained through classical conditioning or any other
Speaker 1: kind of associate of learning. Uh. McConnell and colleagues did
Speaker 1: in fact demonstrate that that's not true, at least for planarians,
Speaker 1: these flatworms that that could be trained to react to
Speaker 1: something like a light stimulus. And we also discussed how
Speaker 1: it's just generally known to be true today that invertebrates
Speaker 1: can learn. The conventional wisdom at the time was wrong.
Speaker 1: But so to pick up with McConnell's career. After completing
Speaker 1: his graduate degree at the University of Texas, I almost
Speaker 1: said Jerry O'Connell, not Jerry O'Connell. James McConnell moved on
Speaker 1: to the University of Michigan, where he continued his research
Speaker 1: into flatworms. So the team that came to be known
Speaker 1: as the Pollinarian Research Group or pr G. So another
Speaker 1: piece of context for this research is a sort of
Speaker 1: quest for the holy Grail within twentieth century psychology and neuroscience,
Speaker 1: and this was the hunt for the elusive Ingram. It
Speaker 1: was believed by men in the mid century that a researcher,
Speaker 1: that the first researcher to actually pinpoint something known as
Speaker 1: the ingram, would receive the Nobel Prize for their work.
Speaker 1: But what was the ingram? The short version is that
Speaker 1: the ingram was believed to be the fundamental physical unit
Speaker 1: of memory represented in the body. In order for an
Speaker 1: animal to learn an association between two things, that memory
Speaker 1: has to be accompanied by some kind of physical change
Speaker 1: inside the body. But what is the fundamental unit of
Speaker 1: that change? Is it a structural change in the brain
Speaker 1: that can be located, or is it something else. So
Speaker 1: the idea is that you would see the physical evidence
Speaker 1: of learning and then potentially like that is physical evidence
Speaker 1: that could be then manipulated. Of course, yeah, it's sort
Speaker 1: of like searching for the atom. What the atom is
Speaker 1: to matter? The ingram would be to memory, what is
Speaker 1: the fundamental unit that that physically indicates in the body
Speaker 1: a memory has been formed. And of course motivation for
Speaker 1: studying whether simpler organisms like worms and other invertebrates could
Speaker 1: in fact learn associations through classical conditioning was that this
Speaker 1: might help move along the search for the ingram. If
Speaker 1: a biological phenomenon seems too complex to understand in one organism,
Speaker 1: you know, if you can't find it in a rabbit,
Speaker 1: everything is just too complicated. Maybe you can get a
Speaker 1: foothold to understanding by looking for analogous phenomena in simpler
Speaker 1: organisms and then build your way back up, and this
Speaker 1: is a sensible way to go about it, of course.
Speaker 1: Uh So, research in the middle of the twentieth century
Speaker 1: tried to locate the ingram two changes in a specific
Speaker 1: part of the brain and a rat, but these efforts failed.
Speaker 1: In fact, rat brain memory research he demonstrated that there
Speaker 1: was no one location or structure in which the fundamental
Speaker 1: unit of memory association was to be found. Instead, learning
Speaker 1: seemed to involve wide swaths of the rat cortex, and
Speaker 1: today we know that certain regions of the brain are
Speaker 1: especially important for memory. Is, for example, fear based conditioning,
Speaker 1: like if you condition somebody to respond to a stimulus
Speaker 1: through conditioning due to an electric shock. This seems to
Speaker 1: strongly implicate the amygdala, not just fear actually, but other
Speaker 1: types of emotional memory as well. I think, while memory
Speaker 1: of spatial locations and physical maps seems especially to implicate
Speaker 1: the hippocampus, but memories for complex actions maybe finding your
Speaker 1: way around a maze, as was often tried with rats,
Speaker 1: will involve lots of different parts of the brain at once,
Speaker 1: so you can't point to the memory in one specific
Speaker 1: part of the brain. It's using the whole brain. Basically,
Speaker 1: in the nineteen fifties. This wasn't yet clear it was.
Speaker 1: It was just clear that memory, contrary to the expectations
Speaker 1: of many psychologists, couldn't be located in one particular structure
Speaker 1: or single point physical change in the brain. And because
Speaker 1: of the failure of researchers to locate a structural ingram
Speaker 1: at a single point in the brain, some researchers began
Speaker 1: to turned to other explanations, and McConnell was one of them.
Speaker 1: McConnell wondered, what if memories were not stored exclusively in
Speaker 1: structures in the brain. Could you have memories in your hands,
Speaker 1: in your blood, in your guts. Was there a deeper
Speaker 1: chemical rather than structural basis for our memories? And here's
Speaker 1: where the Planarians again become an invaluable research tool in
Speaker 1: looking into could you have memories outside the brain? Could
Speaker 1: there be such a thing as a memory chemical or
Speaker 1: a memory molecule found throughout the body? And yeah, this
Speaker 1: we come back to the regenerative powers of the Planarian.
Speaker 1: We described this in the first episode as being something
Speaker 1: like The Sorcerer's Apprentice, the old Disney animation from Fantasia
Speaker 1: in which the uh what what is it? It's a
Speaker 1: broom that is brought to life to do a particular task,
Speaker 1: to carry water from a well. I think, and yeah,
Speaker 1: it was, it's a well. And then and then Nikki,
Speaker 1: the sorcerer's apprentice in this case uh In is up
Speaker 1: having to to destroy it, so he chops it into
Speaker 1: a million pieces with his axe, and then all those
Speaker 1: millions of pieces, each little sliver of the broom comes
Speaker 1: back to life and grows into a whole new fresh
Speaker 1: of broom with that walks around on two legs and
Speaker 1: carries buckets of water. Right, And this connects to the
Speaker 1: regenerative powers of planaria, because if you cut a planarian
Speaker 1: in half one of these flatworms, just chop it in
Speaker 1: half crosswise, separating the head from the tail. Each half
Speaker 1: of the worm would grow back the part it lost,
Speaker 1: So the decapitated head could regrow a tail, and the
Speaker 1: decapitated tail could regrow ahead, which means regrowing a brain.
Speaker 1: So McConnell's question was, if I condition a flat worm
Speaker 1: to learn something, maybe have a response to a stimulus
Speaker 1: like a flashing light, and then I cut it in half,
Speaker 1: which half of the worm will retain the response. If either,
Speaker 1: Now you might think the answer is obvious, right, Well,
Speaker 1: obviously the head half is where the brain is, so
Speaker 1: the head half will retain the conditioning if either side
Speaker 1: does and the tail half won't, Right that that seems
Speaker 1: like the obvious conclusion, Right, Yeah, that's what you would assume.
Speaker 1: That's what like a basic understanding of monster movies would
Speaker 1: have you assumed. Yes, McConnell found this was not exactly
Speaker 1: true in his experiments on freshwater flat worms called dogs
Speaker 1: a Dorado cephala. If you classically condition the worm to
Speaker 1: respond to a light and then you cut the flat
Speaker 1: worm into two halves, both halves retained the conditioning, and
Speaker 1: in a few cases the tail retained the conditioning more
Speaker 1: strongly than the head. So you could cut the head off,
Speaker 1: the tail would regrow ahead and it would still respond
Speaker 1: like the way it had learned to respond when it
Speaker 1: had its original head. So if all the learning was
Speaker 1: in the brain, how could that be possible? Right? This
Speaker 1: would seem to indicate that there's some sort of memory
Speaker 1: retention or memory storage going on within the body itself, right,
Speaker 1: And these was else were eventually published in the Journal
Speaker 1: of Comparative and Physiological Psychology. But then it gets even
Speaker 1: weirder because we're going to start playing flatworms Ship of Theseus?
Speaker 1: Uh so refresher on the Ship of Theseus? Thought experiment, Robert,
Speaker 1: do you want to do the honors here? Oh? Sure?
Speaker 1: This is the basic idea. If you you have this ship,
Speaker 1: for this legendary Ship of Theseus, you're celebrating it across
Speaker 1: the decades. Think about it. Is a ship that is
Speaker 1: docked for decades tends to fall apart piece by piece,
Speaker 1: so you replace it piece by piece. Eventually you reach
Speaker 1: the point where you have replaced every single piece of
Speaker 1: this vessel. The question is, is the Ship of Theseus
Speaker 1: any longer? The Ship of Theseus? Is it? It's it's
Speaker 1: not physically the same ship it was before, but it
Speaker 1: is the same shape. It's just all the pieces have
Speaker 1: been at this point replaced. Now, what if you in
Speaker 1: fact do this with flatworms since they can regenerate, And
Speaker 1: this is exactly what they tried. In a series of experiments,
Speaker 1: McConnell and the Planarian Research Group showed that if you
Speaker 1: cut a worm, like, for example, you cut a flat
Speaker 1: worm's head off after it's been conditioned and trained, so
Speaker 1: it has this memory response and then that tail regrows ahead,
Speaker 1: and then you cut the original tail off, so the
Speaker 1: regenerated head regrows a tail. Now you've got no original
Speaker 1: part of the worm left. So you've been through these
Speaker 1: multiple generations of cutting a worm apart and letting it regenerate.
Speaker 1: And yet their experiments found that some learning training memory
Speaker 1: was retained across the multiple generations where there was no
Speaker 1: original part of the worm left. Again, how would this
Speaker 1: be possible, Like, if memories are stored exclusively in the brain,
Speaker 1: how could a memory necessary to establish a conditioned response
Speaker 1: still operate within a tail that had its head cut off,
Speaker 1: or a segment of a worm grown from a segment
Speaker 1: of a worm grown from a segment of a worm
Speaker 1: that had been through the conditioning. And this led McConnell
Speaker 1: to suppose that he had evidence that memory may have
Speaker 1: strong chemical whole components. They're not limited to activity within
Speaker 1: the brain. There could be actual molecules of chemical memory
Speaker 1: coursing through the worm's body. Now, if this were true,
Speaker 1: this would of course be a revolutionary discovery right right right,
Speaker 1: because of course, and it would conceivably apply to other organisms.
Speaker 1: I mean, that's that's the thing. It might force us
Speaker 1: to completely rethink what we thought we knew about memory, right,
Speaker 1: and of course if it were true of flatworms, as possible,
Speaker 1: it would only be true of flatworms. But yeah, you
Speaker 1: don't know where else this would lead. Could it even
Speaker 1: be true of more complex animals. So it was this
Speaker 1: line of research about cut up flatworms retaining memories that
Speaker 1: led actually to the founding of the magazine we talked
Speaker 1: about in the last episode, The Worm Runners Digest. This
Speaker 1: was McConnell's magazine that quite strangely combined both real research
Speaker 1: on on planarians. It was like real flatworm research published
Speaker 1: alongside weird poems and and joke articles and satirical articles
Speaker 1: and stuff. It's such a weird title. The worm part
Speaker 1: clearly relates to the worm experiments, but it also brings
Speaker 1: to mind like blade Runner, except it's worm Runner. And
Speaker 1: it also makes me think of various Gary Larson far
Speaker 1: Side cartoons which a worm is perhaps, you know, wearing
Speaker 1: sweatpants and linn running. That's good, But the joke and
Speaker 1: title in the title is actually a reference to like
Speaker 1: common terms used by psychologists of this period, lots of
Speaker 1: research about learning and memory involves rats and mazes, and
Speaker 1: so researchers who did this kind of work referred to
Speaker 1: themselves jokingly in the nineteen fifties as rat runners. McConnell's
Speaker 1: variation is self explanatory. Jerry the worm runner. Okay, not Jerry, Jarry,
Speaker 1: Jerry O'Connell, James Ry myself there, James the worm runner then,
Speaker 1: but yeah, actually so coming back. So this led to
Speaker 1: the founding of this strange magazine that he became very
Speaker 1: well known for. The story has summarized by Larry Stern,
Speaker 1: and I mentioned and several sources at the beginning of
Speaker 1: the last episode. We're still referring to those sources in
Speaker 1: this episode. One was an article by Larry Stern that
Speaker 1: that talked about the founding of this magazine. So in
Speaker 1: nineteen nine, McConnell presented some of this work, uh, this
Speaker 1: work about chopping up flatworms and then supposedly retaining memories
Speaker 1: to an annual convention of the American Psychological Association the
Speaker 1: a p A. And this included results collected by a
Speaker 1: member of the Planarian Research Group named Riva Jacobson. And
Speaker 1: again this research showed that not only could a decapitated
Speaker 1: flatworm retain associate of learning, but essentially the ship of
Speaker 1: theseus flatworm containing no tissue of the original worm could
Speaker 1: also retain learning, and after the presentation, Newsweek published an
Speaker 1: article summarizing the research. This led to a huge surge
Speaker 1: of popular interest in McConnell's work, and so Larry Stern
Speaker 1: writes quote. Shortly after the Newsweek coverage, McConnell was inundated
Speaker 1: with letters from high school students from around the country
Speaker 1: asking where they could obtain worms for their projects and
Speaker 1: how they should go about caring for and training them.
Speaker 1: Some students, according to McConnell, demanded that he sent them
Speaker 1: a few hundred trained worms at once, as their projects
Speaker 1: were due within days. It sounds a little familiar, right,
Speaker 1: Students don't do things like this, but McConnell did want
Speaker 1: to help students conduct their own flatworm research. I get
Speaker 1: the feeling he was into this idea, but he realized
Speaker 1: very quickly that it didn't make sense to try to
Speaker 1: respond to each letter individually, so instead he decided to
Speaker 1: publish a manual on how to replicate the experiments performed
Speaker 1: by the PRG, and he titled this document The Worm
Speaker 1: Runners Digest. However, after publishing this manual under that title,
Speaker 1: McConnell started getting submissions to appear in future issues. So
Speaker 1: he began publishing this so called journal on a regular basis, again,
Speaker 1: including both real research and psychological in jokes, cartoons, poems,
Speaker 1: and all that kind of stuff interwriting. So it's kind
Speaker 1: of accidentally became a continuing publication. Yeah. Now, as you
Speaker 1: can magine, some people didn't take kindly to this mix
Speaker 1: of subject matter. In nineteen sixty four, after some readers
Speaker 1: complained that they couldn't tell the real research from the
Speaker 1: jokes and the satire, they started publishing the satirical elements
Speaker 1: upside down in the back half of the journal. So
Speaker 1: there was some attempt there to clear up the confusion.
Speaker 1: But I think for a lot of scientists the pure
Speaker 1: proximity of the different material was was a problem no
Speaker 1: matter how clear the division. Well, I think that's understandable.
Speaker 1: We talked before about the Ignoble Prizes, for instance, about
Speaker 1: most of the individuals involved and honored by these prizes
Speaker 1: that celebrate, you know, scientific studies that are legitimate scientific studies,
Speaker 1: but that are on some level humorous or amusing. But
Speaker 1: you still have some individuals in the scientific world who
Speaker 1: do not see the value of that. So if they're
Speaker 1: so if feathers are ever ruffled by the ignoble prizes,
Speaker 1: obviously something like this would ruffle feathers as well. Yes,
Speaker 1: uh so, Then in nineteen sixty seven there came another
Speaker 1: split where the serious half of the journal was just
Speaker 1: formally cleaved and renamed, in fact cloven in half like
Speaker 1: a flatworm, uh, chopped right off, decapitated. The serious half
Speaker 1: was renamed the Journal of Biological Psychology, and the worm
Speaker 1: runners Digest became the soul Haven of Humor, and it
Speaker 1: continued publishing that way until all Right, on that note,
Speaker 1: we're going to take a quick break, but we will
Speaker 1: be right back. Than alright, we're back, alright, So to
Speaker 1: jump back into the progression of James McConnell's research, we're
Speaker 1: we're brought back to this question of a non brain
Speaker 1: chemical basis for memory. Couldn't memory, or at least some memory,
Speaker 1: some types of memories be stored chemically rather than structurally
Speaker 1: dispersed in the body in molecules, And here's where we
Speaker 1: get to the cannibalism. So, if there were in fact
Speaker 1: molecules within an animal representing some kind of chemical memory,
Speaker 1: such as memory of how to navigate a maze, could
Speaker 1: this be demonstrated? Could those molecules be shared from one
Speaker 1: animal to another? And this makes sense. That's what creatures do.
Speaker 1: They take molecules from each other, from other organisms and
Speaker 1: put them into themselves. Sure, we absorbed the molecules existing
Speaker 1: in other organisms for nutrition. Uh, so maybe you could
Speaker 1: molecules be absorbed from one organism to another four memory transfer.
Speaker 1: So the first method they tried, uh and this is
Speaker 1: based on the reporting of one of those Larry Stern articles.
Speaker 1: The first method they tried was to splice the head
Speaker 1: of a conditioned worm onto the tail of an unconditioned
Speaker 1: worm to see if it would share molecules right, to
Speaker 1: force them to exchange the alleged memory molecules. But the
Speaker 1: transplant did not work. The head would not stay attached.
Speaker 1: Then they tried to liquefy fully conditioned flat worms and
Speaker 1: inject their juice into untrained worms, but this was also difficult.
Speaker 1: The planarians were too small to be injected basically, and
Speaker 1: sometimes they exploded when injected. In Larry Stern's words quote
Speaker 1: it was like trying to impay all a prune with
Speaker 1: a javelin a lot of horrific things done to to
Speaker 1: planarians in these experiments. I guess they are a simple
Speaker 1: enough organisms that we have to be so upset about them,
Speaker 1: I guess, But it's still one can't help it. Pause
Speaker 1: a little on some of these, right, some of the grinding, Yeah,
Speaker 1: the sauce, the gravy, the flatworm sauce. So how do
Speaker 1: you get those hypothetical memory molecules in there? If you
Speaker 1: can't inject them, you can't transplant ahead on. So the
Speaker 1: next route they tried, and this was in the year
Speaker 1: nineteen sixty, was experimental planarian cannibalism. This would be the
Speaker 1: old fashioned way of getting molecules from one organism into
Speaker 1: the other. Sure, so apparently the idea came from a
Speaker 1: flatworm researcher named Jay Boyd Best who communicated to McConnell
Speaker 1: about the fact that one particular species of planarian was
Speaker 1: known for cannibalistic behavior. So here's the answer. You train
Speaker 1: the worms to respond to to a maze or to
Speaker 1: the light, whatever the conditioning stimulus is, and then they
Speaker 1: learn the conditioning and then you grind them up into
Speaker 1: worm gravy, and then you feed the worm gravy to
Speaker 1: the untrained naive worms, and you see what happens, and astonishingly,
Speaker 1: their early experiments with this method looked very promising, including
Speaker 1: a number of early replication attempts with blinding procedures to
Speaker 1: remove the possibility of experiment or bias, supposedly confirming their
Speaker 1: early results. So, if it were true that memory molecules
Speaker 1: are being exchanged through this strange cannibalistic ritual, could I,
Speaker 1: you know, with this extend to humans? Could could I
Speaker 1: drink your flesh and gain your memories? And how was
Speaker 1: it happening? What was the chemical basis here? So one
Speaker 1: interesting line of reasoning here followed from the still somewhat
Speaker 1: recent discoveries about genetic information being stored in and mediated
Speaker 1: by nucleic acids DNA and RNA. Remember, you know, we're
Speaker 1: not too far from from the discovery of the double
Speaker 1: helix here. So if DNA and RNA could be involved
Speaker 1: in an information management process passing genetic information across generations
Speaker 1: from parents to offspring, could the same molecules also in
Speaker 1: code and mediate other types of information? I mean information
Speaker 1: is in the DNA. So specifically, could the information content
Speaker 1: of memories somehow be coded into DNA or RNA and
Speaker 1: then dispersed through the body, but also transferred from one
Speaker 1: body to another. And so this is the line they took.
Speaker 1: McConnell and his team conducted experiments and published results that
Speaker 1: seemed to back up the idea, at least for a while,
Speaker 1: that RNA played some important role in facilitating memory, and
Speaker 1: that RNA could be used to chemically inoculate naive worms
Speaker 1: with the memory associations of their more worldly predecessors. And again,
Speaker 1: just consider how revolutionary this would be if it turned
Speaker 1: out to be true. You'd be forced to wonder how
Speaker 1: far the principle could be taken. Did this only apply
Speaker 1: to planarians or did it extend to other more complex animals.
Speaker 1: Would there be ways in which humans could undergo chemical learning?
Speaker 1: Could you train the mind in some way with an
Speaker 1: injection alone, or even a pill? Even if it only
Speaker 1: worked for like broad associative learning such as you know,
Speaker 1: the kind of things you get through classical conditioning with
Speaker 1: an electric shock and a single stimulus, you could still
Speaker 1: possibly imagine profound benefits. Just one idea comes to mind, like,
Speaker 1: say you're struggling with a drug addiction. Could you seek
Speaker 1: out an injection of of memory molecules to establish a
Speaker 1: strong averse reaction to your drug of choice such that
Speaker 1: you wouldn't want to take it anymore. Yeah, Or to
Speaker 1: get into some of the behavioral his ideas that we
Speaker 1: discussed in the first episode, some of those ideas that
Speaker 1: that that McConnell's very outspoken about it, even later in life.
Speaker 1: You could have some sort of a cocktail that could
Speaker 1: be injected into an individual that had a history of
Speaker 1: violence and history of of you know, breaking the law
Speaker 1: and rebelling against authority figures, and you could can potentially
Speaker 1: fix them with this injection. Yeah. And of course there
Speaker 1: you get into the more nefarious possible thing, Like you
Speaker 1: can probably instantaneously imagine so many horrible, insidious uses for
Speaker 1: injectable conditioning if such a thing were possible. Oh yes,
Speaker 1: I mean, as with any science, many many fabulous uses
Speaker 1: come to mind, but so many nightmares as well. But
Speaker 1: we should stop and be real for a second here,
Speaker 1: that even if these findings had turned out to be
Speaker 1: totally solid for planaria and more on, that in a moment,
Speaker 1: we should know better than to freely extrapolate from worms
Speaker 1: to humans. I think this is one of the most
Speaker 1: classic traps that people fall into and interpreting biological research.
Speaker 1: I'd say more often as people extrapolating from like rats
Speaker 1: to humans. But this isn't a much larger jump. This
Speaker 1: isn't even a vertebrate animal. Yeah, I mean, you can't help.
Speaker 1: I often find that I can't help, but but at
Speaker 1: least think about that on some when I read a
Speaker 1: science headline, I can't help it. Put myself into into
Speaker 1: it somehow and imagine myself as the creature, right, And
Speaker 1: it's often, I mean, it's just done right there in
Speaker 1: the press. Again, it's fine to wonder about what possibilities
Speaker 1: could be implied by studies in rats for humans, but
Speaker 1: you can't just, you know, conclude from one to another.
Speaker 1: We can't help but anthropomorphize virtually any creature, and if
Speaker 1: that creatures in a study, we're also going to end
Speaker 1: up anthropomorphizing that as well. But James McConnell, true to form,
Speaker 1: as we know from the last episode, was not one
Speaker 1: to be shy or cautious about interpreting his findings. He
Speaker 1: loudly proclaimed them to the public, advertising his results on
Speaker 1: TV programs. He apparently embraced the nickname mccannibal uh, and
Speaker 1: he predicted an era of memory pills like we just discussed,
Speaker 1: So you might be thinking, like, wait a minute, he
Speaker 1: should know better than to extrapolate from planarian even if
Speaker 1: you assume the planarian research to be solid and will
Speaker 1: introduce some caveats to that. But even if you did
Speaker 1: assume that, how could you jump from that to human
Speaker 1: memory pills? That seems like a you know, a leap
Speaker 1: of miles of assumptions. Yeah, very much though, And it
Speaker 1: does seem from from what I was reading, especially in
Speaker 1: Rilling's paper about McConnell, that it seemed like to him
Speaker 1: he sort of had a sense of humor about talking
Speaker 1: about memory pills, like as if he were sort of
Speaker 1: joking when he talked about memory pills. But that was
Speaker 1: not clear to the popular audience that was listening on
Speaker 1: the TV. You know, they weren't psychologists. They didn't understand
Speaker 1: that he was kind of kidding when he said. That
Speaker 1: makes sense, oh, certainly. And then also, they're going to
Speaker 1: be like a few different levels, so I could like,
Speaker 1: he may joke about it here in this paper, or
Speaker 1: joke about it to this individual, but then you're gonna
Speaker 1: have different levels of coverage, and it's going to get
Speaker 1: out of out of control pretty quickly. Yes, So Rilling
Speaker 1: writes that quote McConnell's work on retention following regeneration and
Speaker 1: planaria provides a case study in sensational journalism and illustrates
Speaker 1: how his media work escaped the normal mechanisms of peer review.
Speaker 1: So the idea is that McConnell and colleagues would do
Speaker 1: an experiment, they would obtain a very strange and interesting
Speaker 1: result that looked solid enough to get published in an
Speaker 1: academic journal, and then McConnell would immediately want to engage
Speaker 1: in quote, wild sounding conjectures interpreting the meaning of his
Speaker 1: results and how they would be applied in the future,
Speaker 1: and scientific journals generally like one example was the editor
Speaker 1: Harry harlow Uh generally refused to publish these wild interpretive
Speaker 1: or speculative addendums to the research. They just say, well,
Speaker 1: we'll publish your study, you gotta cut out this section
Speaker 1: about memory pills that doesn't belong in here. But of
Speaker 1: course there's no peer review in the popular media, so
Speaker 1: he could go on TV and say memory pills as
Speaker 1: much as he wanted, And it turned out that that
Speaker 1: kind of thing on TV gets you booked on TV
Speaker 1: again because it's exciting right. I mean, that's like something
Speaker 1: that people in picture, it's not hard to understand, and
Speaker 1: it's it's very like what revolutionary. That's what you want
Speaker 1: in a science segment on your your news programs. You
Speaker 1: want something relatable, and here's this guy that is making
Speaker 1: it relatable and exciting with promises that are not at
Speaker 1: all implied by the research being discussed. Even if the
Speaker 1: research itself is a solid and and retrospectively that may
Speaker 1: be in doubt. So just one example, in nineteen fifty nine,
Speaker 1: an article in Newsweek covering McConnell and the PRG research
Speaker 1: claimed it may be that in schools of the future,
Speaker 1: students will facilitate the ability to retain information with chemical injections. Apparently,
Speaker 1: there was also a lot of misunderstanding in the media,
Speaker 1: misunderstanding the fact that multiple generations of regenerated Planaria could
Speaker 1: retain training, and they misunderstood this is the fact that
Speaker 1: memories can be inherited in apparent to child sense, which
Speaker 1: led to all kinds of Lamarckian interpretation. So I think
Speaker 1: there there's all. There was also just confusion stemming from
Speaker 1: the use of the word inherited and generations he was
Speaker 1: talking about like generations being chopped up and regenerating, which
Speaker 1: is quite different than what we understand, right, And again
Speaker 1: he's coming down. He's talking about memories here. There are
Speaker 1: other things that you know, there's certainly things that affect
Speaker 1: that have generational effects in biology and in human biology.
Speaker 1: I think we've talked about studies before and about body
Speaker 1: size following periods of starvation, that sort of thing. But
Speaker 1: but again we're talking about memories here. He is explicitly
Speaker 1: talking about memory. Yes, And another one that that was
Speaker 1: quoted in Rilling was regarding cannibalistic memory transfer, the one
Speaker 1: where you eat the worm gravy and you gain that
Speaker 1: worm's memories. Supposedly, there was a nineteen sixty four article
Speaker 1: in the Saturday Evening Post that claimed we quote might
Speaker 1: someday enable us or it might someday enable us to
Speaker 1: learn the piano by taking a pill, or to take
Speaker 1: calculus by injection, which at that point is is very crude,
Speaker 1: gross kind of like over interpretation of what the memories
Speaker 1: here all are. And the you know, the leap from
Speaker 1: one organism to another, you just like do a line
Speaker 1: of ground up Beethoven, And yeah, I mean this is
Speaker 1: this is so outrageous that like I, I feel like
Speaker 1: I would I would feel like I was over stretching
Speaker 1: to use this as an outrageous example of a possibility,
Speaker 1: you know, like earlier I I did the the far
Speaker 1: future example of of criminals being treated like this seems
Speaker 1: even this is even seems crazier, but on the same hand,
Speaker 1: also attractive the idea of being able to uh, say,
Speaker 1: master calculus by simply injecting something into your body. Yeah,
Speaker 1: though I hope Also our questions about potential applications if
Speaker 1: this were true were heavily caveat. So in the mid
Speaker 1: nineteen sixties there were even studies following up on this
Speaker 1: cannibalism research claiming to bear out chemical memory transferring other species,
Speaker 1: such as in rats. Again, that's kind of hard to believe,
Speaker 1: and so like. For a few years there in the sixties,
Speaker 1: things looked incredibly promising with this research. But fortunately or unfortunately,
Speaker 1: depending on how you look at it, it was not
Speaker 1: too lad. There was a problem with the p RGS
Speaker 1: cannibalistic memory transfer research, and it was just that it
Speaker 1: didn't hold up to sustained scrutiny over time. Over time,
Speaker 1: properly blinded and controlled efforts to replicate McConnell's results. A
Speaker 1: few of them came in saying yeah, we replicated, but
Speaker 1: a lot did not produce the same effects for cannibalism
Speaker 1: or other chemical methods of memory transfer. According to Rilling
Speaker 1: in nineteen seventy one, I guess this would be as
Speaker 1: a result of some of these failures, the Plenaryan research
Speaker 1: group lost its grant support, and this led McConnell to
Speaker 1: change focus. And after this in the seventies he went
Speaker 1: on to write a very influential and from what I
Speaker 1: can tell, mostly well regarded textbook for introductory psychology. Apparently,
Speaker 1: one thing that set it apart in the field was
Speaker 1: that it used a lot of fiction. It introduced students
Speaker 1: to psychological research methods with the use of stories and
Speaker 1: like fictional framing narratives to explain the principles that were
Speaker 1: discussed in each chapter. UH, even including one chapter about memory.
Speaker 1: It seems to begin with a fictionalized version of the
Speaker 1: story of his research with Thompson in nineteen fifty four
Speaker 1: or so, UH, though incorporating lessons about control groups that
Speaker 1: he had not learned very well back then, and as
Speaker 1: we discussed more in the previous episode. Later in his career,
Speaker 1: I think he was known more maybe for being a
Speaker 1: fierce public advocate of the powers of behavior modification through conditioning. Again,
Speaker 1: this was an era in which behaviorist psychology was seen
Speaker 1: by many as a potentially revolutionary scientific tool for minute
Speaker 1: control of human minds and lives. This is the birth
Speaker 1: of the modern concept of brainwashing. Right and McConnell wrote
Speaker 1: and appeared on TV arguing that behavioral conditioning would fundamentally
Speaker 1: alter the nature of criminal justice in democratic society itself.
Speaker 1: I think there was one article he wrote that was
Speaker 1: titled something like we must brainwash criminals. Now, well, that's
Speaker 1: a great headline though, no doubt about it. Yeah, certainly
Speaker 1: if you want to get the clicks. Uh, yeah he
Speaker 1: was maybe he maybe he was clickbait before the Internet.
Speaker 1: He does, he does seem very CLICKBAITYU. And this is
Speaker 1: something some of his colleagues said about them. Is quoted
Speaker 1: in the Rilling paper that he wanted to shock people.
Speaker 1: He wanted to say things that would make people say,
Speaker 1: what what's this guy talking about? That can't be true?
Speaker 1: And he said, you know, the idea was you you
Speaker 1: bring people in by shocking them, and then you educate
Speaker 1: them with the science. And you know, I guess that
Speaker 1: can be an okay method if what you if what
Speaker 1: you say in order to shock people isn't fundamentally dishonest
Speaker 1: in some way, right, Yeah, I mean it's it's kind
Speaker 1: of it kind of gets into a similar of like
Speaker 1: leading with an example, you know, and sometimes it's an
Speaker 1: outrageous example. Sometimes, like on this show, we we bring
Speaker 1: up a monster, something fantastic, and we use that to
Speaker 1: talk about something that is that is real and talk
Speaker 1: about actual scientific studies or actual biology that somehow matches
Speaker 1: up to that. But well, I hope we never do.
Speaker 1: I hope if we start with god Zilla, we don't
Speaker 1: leave you with the impression at the end of the
Speaker 1: episode that god zills real and true. But it is
Speaker 1: interesting how it seems like some of the things that
Speaker 1: did make him such a great communicator and ultimately like
Speaker 1: a great author of an introductory psychology book. Uh, those
Speaker 1: are also some of the things that got him in trouble. Yeah,
Speaker 1: that totally seems to be true based on everything I've read.
Speaker 1: But but coming back to the the memory transfer issue,
Speaker 1: I just want to say that I think the conclusion,
Speaker 1: unfortunately at the end is that the cannibalistic memory transfer
Speaker 1: saga is widely regarded now as a dead end. Despite
Speaker 1: a few reports of moderate replication successes, McConnell's results ultimately
Speaker 1: did not hold up to widespread scrutiny and the rigorous
Speaker 1: application of controls by others. And it looks like his
Speaker 1: supposed discoveries about memory transfer through injection or cannibalism were
Speaker 1: probably wrong, but not all of his conclusions were necessarily wrong.
Speaker 1: I mean again, One of the points of Rilling's article
Speaker 1: seems to be that despite the ultimate failure of the
Speaker 1: memory transfer through cannibalism theory, McConnell did make truly important
Speaker 1: contributions to research on invertebrate learning in the nineteen fifties.
Speaker 1: And while the memory transfer the memory molecule transfer through
Speaker 1: cannibalism is almost definitely a dead end, more recent studies
Speaker 1: have sort of raised the question of whether his like
Speaker 1: decapitation and transplantation research might have been on the right track.
Speaker 1: All right, we're gonna take one more break. When we
Speaker 1: come back, we're going to discuss some of these modern
Speaker 1: follow ups regarding polanaryan decapitation and brain transplant Thank alright,
Speaker 1: we're back so we discussed through through the end of
Speaker 1: the career of of James V. McConnell, who studied planarians
Speaker 1: memory memory transfer our memories outside of the brain, and
Speaker 1: we we brought up the idea that this subject has
Speaker 1: been revisited by researchers just in the past few years
Speaker 1: who think that while McConnell was probably wrong about like say,
Speaker 1: eating flat worms and gay in their memories, there may
Speaker 1: be some truth to the idea of memories somehow being
Speaker 1: stored outside the brain or transferred without a full brain. Yeah. So,
Speaker 1: for instance, it has been demonstrated that if you transplant
Speaker 1: the planarians brain into another worm's body, uh, it will
Speaker 1: result in at least partial recovery of function, even if
Speaker 1: the brain is put in backwards or transplanted across species. Uh.
Speaker 1: The author Pagan, who we brought up earlier, who wrote
Speaker 1: the first brain UH, he points this out, and he
Speaker 1: points out that basically the cross species transplants held, meaning
Speaker 1: there was no rejection and forty eight hours later the
Speaker 1: worm retained mostly normal behavior. I mean, that's pretty weird,
Speaker 1: but again it's worms. Like Yeah. One of the big
Speaker 1: take comes from all of this is that planarian brains
Speaker 1: and plinarian in general are strange, right, So a lot
Speaker 1: of what we determine what a lot of what we
Speaker 1: learned from this research you could interpret as some fascinating
Speaker 1: deeper inside about biology g as a whole, or you
Speaker 1: could interpret it as fascinating specific facts about these flatworms. Absolutely.
Speaker 1: Uh so in particular, though a gun and there's are
Speaker 1: referring to a study by Davies at all, and they
Speaker 1: were working with a species of planarium that actually can't
Speaker 1: regenerate brain tissue, but a transplanted brain will take root
Speaker 1: and quote nerves exiting the brain tended to join with
Speaker 1: the peripheral nerves closest to them, which I think is
Speaker 1: a wonderful image of the brain being implanted in this creature.
Speaker 1: And then like the like the like roots forming, like
Speaker 1: the vein, he connects itself. It hooks itself up like
Speaker 1: a car battery that has been placed in the inside
Speaker 1: another via a new vehicle, and all the things just
Speaker 1: kind of hook up automatically, plug and play. Yeah. Well,
Speaker 1: or like like mistletoe or some other kind of parasite
Speaker 1: that like sticks it's little it's how stori um or whatever,
Speaker 1: the little spikes down into the host. Yeah, it's it's
Speaker 1: it's weird. It's definitely not the human experience. I mean
Speaker 1: not to not to discuss, you know, the whole body
Speaker 1: transplant or human brain and head transplant much in this episode,
Speaker 1: but basically it's very complicated, if not impossible in humans. Yeah. Well,
Speaker 1: and again to look at memory more broadly, neuroscientists today
Speaker 1: mostly broadly understand memories to be neural networks, right, networks
Speaker 1: within the brains, sort of strings of reinforced connections between
Speaker 1: neurons and brain regions that specify memories by their cross
Speaker 1: linked structure. A memory is in some way a series
Speaker 1: of connections between neurons and the brain. Uh. Though that
Speaker 1: does seem to be the case. Beyond that broad picture,
Speaker 1: there's still a lot we don't know about the physical
Speaker 1: basis of memory, and so even in especially in organisms
Speaker 1: like flatworms, there are ways in which memory could be
Speaker 1: operating and that are still mysterious to us right now.
Speaker 1: Of course, the quest to solve these mysteries continues. Uh.
Speaker 1: Great deal of pollinarian research is still going on, and
Speaker 1: you see quite a bit of it come out of
Speaker 1: Tufts University, and you'll see um, a researcher by the
Speaker 1: name of Michael Levin often is a is a head
Speaker 1: author or co author or contributing author on these papers. Yeah,
Speaker 1: and there was one big study that got some press
Speaker 1: being connected back to McConnell's research that Levin was at
Speaker 1: least one of the authors on UM and and basically
Speaker 1: it had to do with replicating a version of the
Speaker 1: decapitation experiment showing that somehow it appeared memory if the
Speaker 1: study was designed properly and there wasn't some kind of
Speaker 1: flaw that people didn't notice in there, that memories maybe
Speaker 1: were somehow being transferred through the decapitation process. Right. This
Speaker 1: is a two thousand thirteen Tough University study that found
Speaker 1: that a decapitated flat worm that grows a new head
Speaker 1: keeps its old memories. Uh. For instance, the Sarahsing article
Speaker 1: about this it appeared in Nautilus, carried the title decapitation
Speaker 1: but not cannon is um might transmit memories without context.
Speaker 1: That's a pretty weird title, right, But then within context
Speaker 1: the article refers back to McConnell's work quite a bit.
Speaker 1: And the idea here is that some trace of the
Speaker 1: of memory might be stored in neural circuits outside the
Speaker 1: brain and certainly when you take that and you compare
Speaker 1: it to these you know, these other into this previous study. Uh,
Speaker 1: with with one brain being dropped into a new creature,
Speaker 1: a new a new individual and seeing it, you know,
Speaker 1: take root and uh and seemingly bounce back. Uh, that
Speaker 1: becomes all the more interesting. Yeah. One of the things
Speaker 1: that has clearly been the case, and this was discussed
Speaker 1: in that article in the Verge we talked about in
Speaker 1: the last episode, is that Levin's research has been focused
Speaker 1: on trying to eliminate some of the problems that could
Speaker 1: have existed in the original McConnell research. One example is
Speaker 1: that that he helped create um and a thing called
Speaker 1: an automatic training apparatus. Basically, it's a robot for conditioning
Speaker 1: the flatworms, take the human element element out of the
Speaker 1: training process to eliminate any kind of bias or error
Speaker 1: that could be introduced that way. But I love the
Speaker 1: idea in general of a robot for training worms. So
Speaker 1: that that two thousand thirteen study especially generated quite a
Speaker 1: bit of interest, and at the time there was there
Speaker 1: was mixed response from the scientific community. Now, I do
Speaker 1: want to drive home that it is not my interpretation
Speaker 1: that Michael Levan is anything like a McConnell figure. He seems.
Speaker 1: He seems to be a very suffected researcher. And most
Speaker 1: of his work, like I said, he's seeing on a
Speaker 1: lot of studies for his general planaria research right now,
Speaker 1: I mean, I don't. I haven't seen anything where Michael
Speaker 1: Levin is going on TV and saying memory pills right right,
Speaker 1: uh and uh and and by and large it seems
Speaker 1: like most of his work just deals with with regeneration,
Speaker 1: uh in these planaria worms. But yeah, so you had
Speaker 1: plenty of people that that were supportive and thought that,
Speaker 1: you know, they might be onto something. Others were a
Speaker 1: little critical at the time. Robert Kintridge, I say it
Speaker 1: was a psychologist at Durham University, and he pointed out
Speaker 1: in a two fifteen Verge article that Verge article we
Speaker 1: cited earlier that it might be simply related to quote
Speaker 1: behavior induced by a stress hormone itself triggered by the
Speaker 1: textualized petrie dishes unquote. And to clarify, they're part of
Speaker 1: what the study looked at to see conditioning in the
Speaker 1: flatworms was you'd have these textured petrie dishes where they
Speaker 1: would be swimming around the food they were going to eat,
Speaker 1: and how fast they approached the food in a newly
Speaker 1: textured Petrie dish environment was taken as a signal of
Speaker 1: their memory or familiarity with the environment. Like you put
Speaker 1: a new flatworm in a textured Petrie dish, its circles
Speaker 1: for a while before going for the food because it's
Speaker 1: exploring its environment. It doesn't know. But after it's been
Speaker 1: trained with the texture and a Petrie dish, it goes
Speaker 1: straight for the food because it already knows the environment. Right. Yeah.
Speaker 1: So so basically a number of individuals UH said, well,
Speaker 1: there there are aspects of the study that could have
Speaker 1: been better designed. Sure. Now again, Michael Levin, his research continues.
Speaker 1: He and you you'll find a number of studies from
Speaker 1: very recently that he's been involved with. He was an
Speaker 1: author on a study earlier this year neural control of
Speaker 1: body plan access in regenerating planaria. And in two thousand
Speaker 1: fifteen he put out a paper on the planarian regeneration
Speaker 1: model as deciphered by artificial intelligence. And uh that same
Speaker 1: year he was also a co author on another study
Speaker 1: UH that included the growth of extra heads. Yeah, I've
Speaker 1: seen also that I think both within and outside of planaria.
Speaker 1: He's just generally studied regeneration. Yeah, and with the poplinaria,
Speaker 1: of course, it's it's just such an amazingly regenerative creature.
Speaker 1: You get things like like this. Uh, the second study
Speaker 1: that I mentioned from fifteen, they were able to induce
Speaker 1: one species of flat worm to grow heads and brains
Speaker 1: characteristic of another species of flat worm without altering genomic sequence,
Speaker 1: and then the individual later regenerated to the appropriate head shape.
Speaker 1: Now quickly, I guess one thing worth discussing is if
Speaker 1: the research associated with with Michael Levin is in fact correct,
Speaker 1: the results are valid, there's not some kind of flaw
Speaker 1: we're missing in the design of the study. And uh,
Speaker 1: and this is really going on. The memories are surviving
Speaker 1: the regeneration without an original brain. How would you interpret this, Like,
Speaker 1: what does it mean if this is in fact true? Uh?
Speaker 1: So a couple of ideas are given in the Verge article.
Speaker 1: Leven hYP quote hypothesizes that memories could spread beyond the
Speaker 1: brain thanks to electrical charges generated by cells and the
Speaker 1: rest of the body. So there's some kind of information
Speaker 1: encoding that's just like coming from cells in the other
Speaker 1: body that are electrically stimulating something like a memory response.
Speaker 1: But then there's another thing cited in the same piece
Speaker 1: by Ava Jablanca, a developmental biologist at Tel Aviv University,
Speaker 1: and she offers a speculative explanation involving particles called small RNAs,
Speaker 1: which are short copies of DNA, but they don't turn
Speaker 1: into proteins. They don't generate proteins. So when a flatworm
Speaker 1: learns an association or an episode, something in this model
Speaker 1: about the brain chemistry would change, and then these changes
Speaker 1: alter the small RNA is present in the body, which
Speaker 1: of course are not confined to the brain because they
Speaker 1: migrate around between cells. And by migrating around between cells,
Speaker 1: she says, perhaps they end up in stem cells that
Speaker 1: remain in the body. After the worm's head is cut off,
Speaker 1: and to read from the article quote, when the worm's
Speaker 1: head grows back, the small RNA's migrate back to the head,
Speaker 1: changing the brain's chemistry and allowing it to learn certain
Speaker 1: behaviors more quickly. Um If true, the memory that Levin
Speaker 1: thinks is stored outside the brain wouldn't be memory at all. Rather,
Speaker 1: the small RNAs would allow the flatworm to recover a
Speaker 1: brain environment that helps them learn a specific behavior more quickly.
Speaker 1: So the idea there is that if this speculative idea
Speaker 1: is correct, and again she she's very clear to stay
Speaker 1: this this isn't something we know. Is just a speculative interpretation.
Speaker 1: Maybe it works this way, then what would be happening
Speaker 1: is these little chemical molecules don't transmit the memory prepare
Speaker 1: the new brain to learn a memory that was previously
Speaker 1: learned more quickly. Okay, so at least we have a
Speaker 1: hypothetical model of how this would actually work, which or
Speaker 1: at least here's one model presented anyway, Sure, but ultimately
Speaker 1: we don't know for sure. And again another thing that
Speaker 1: we don't know for sure is if these results do
Speaker 1: hold up. Is this something that's specific to planaria? Is
Speaker 1: it flatworms only that can transfer memories in this way
Speaker 1: or could this be more applicable beyond flatworms to other organisms,
Speaker 1: because that's the thing. Other organisms can't regenerate like a
Speaker 1: like a planaria can. But at the same time, we
Speaker 1: one of the one of the things that's often cited
Speaker 1: for researching an area regeneration is that we might learn
Speaker 1: something that could be appliable to humans. Of course, especially
Speaker 1: and with not even getting into memory implantation, just the
Speaker 1: idea that they have such impressive neural regenerative powers, the
Speaker 1: ability to regenerate like damaged brain cells. You know, if
Speaker 1: we could, if we could develop some better method of
Speaker 1: doing that based on our studies of these organisms, then
Speaker 1: that would be tremendous. Of course. I mean though it
Speaker 1: when you introduce the idea of brain regeneration or anything
Speaker 1: like that to a human context, things emerge that don't
Speaker 1: necessarily seem to be of concern. When you're talking about planaria.
Speaker 1: Planaria don't seem to have extremely distinct personalities. Uh, you
Speaker 1: know humans do you know, however much we want to
Speaker 1: joke about humans acting like sheep and all being the
Speaker 1: same we you know, we we've got a lot of
Speaker 1: different stuff going on in our heads. If you cut
Speaker 1: your head off and regrow it, what indication would you
Speaker 1: have that the new head would be you in any
Speaker 1: sense other than sharing your d n A. Well, I
Speaker 1: guess as long as it's said all the right things
Speaker 1: and I mean just get along just fine, it would
Speaker 1: be like a p zombie perhaps, Well, I mean, would it?
Speaker 1: I guess it would be a question of whether it
Speaker 1: would retain any memories from your life, you could you
Speaker 1: talk about whether that might be stored in the body somehow,
Speaker 1: or even if you assume it, okay, it retains no
Speaker 1: memories whatsoever because those are just stored in the brain.
Speaker 1: Whatever may or may not be happening in flatworms doesn't
Speaker 1: happen and all at all in humans. Even if you
Speaker 1: assume all that, you'd also have to ask, like, would
Speaker 1: its personality be the same as yours personality is so
Speaker 1: shaped by life experience? I don't know. It makes me
Speaker 1: wonder has anyone ever considered creating a like a science
Speaker 1: fiction yarn in which you look at what would human
Speaker 1: society be like if we had regenerative properties like this?
Speaker 1: Like what would war be like? What would what would
Speaker 1: reproduction and society be like? I mean, granted, I think
Speaker 1: the obvious answer, it would absolutely change everything. But the
Speaker 1: fun thing about science fiction is you don't you don't
Speaker 1: have to go all the way. You can just sort
Speaker 1: of like tweak it, like what would this if we
Speaker 1: if I were to look at this particular vision for
Speaker 1: a totally regenerative plnary in human species, then what could
Speaker 1: I perhaps unravel about our actual human condition? Well? I mean,
Speaker 1: I think we pretty much all at some state, at
Speaker 1: some point or other, get into a get into a
Speaker 1: place where not very happy with our own brain. We
Speaker 1: don't like the emotional patterns were feeling. Maybe we're ruminating
Speaker 1: in bad ways. I mean, this happens pretty often to people.
Speaker 1: So what if you had the option to you get
Speaker 1: into a bad state like that, you know, you can
Speaker 1: just cut your head off and grow a new one.
Speaker 1: These are exactly what the horrifying orange creatures in Labyrinth
Speaker 1: they're all about when they come up to Sarah and
Speaker 1: they encourage your Hey, take your own head off, throw
Speaker 1: it around, try on a different head, Let your head
Speaker 1: try it out, try itself out on a different body,
Speaker 1: see how it shakes out. Just you know, have to
Speaker 1: have a little fun. You're not a flat worm. Don't
Speaker 1: try it people. All right, We're gonna go ahead and
Speaker 1: close this out then, but we hope you have enjoyed
Speaker 1: and then learned from this exploration. Perhaps you'll think of
Speaker 1: flat worms in a new light now, and perhaps you
Speaker 1: will even second guest memory a little bit as well.
Speaker 1: In the meantime, if you want to check out other
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