WEBVTT - Devourer of Memories, Part 2 0:00:00.120 --> 0:00:04.760 My Welcome to Stuff to Blow Your Mind, a production 0:00:04.800 --> 0:00:13.560 of I Heart Radios How Stuff Works. Hey, welcome to 0:00:13.600 --> 0:00:15.800 Stuff to Blow Your Mind. My name is Robert Lamb 0:00:15.960 --> 0:00:18.160 and I'm Joe McCormick, and we're back with part two 0:00:18.239 --> 0:00:23.320 of our exploration of planarians, memory, learning and conditioning, and 0:00:23.440 --> 0:00:25.720 of course today we're going to get to the cannibalism. 0:00:25.760 --> 0:00:27.600 That's right. If you did not listen to part one, 0:00:27.640 --> 0:00:29.280 do go back and listen to it, because we lay 0:00:29.320 --> 0:00:32.680 the groundwork. We discussed these organisms, why they're interesting. We 0:00:32.720 --> 0:00:36.720 discussed their regenerative powers. We talk about McConnell himself. We 0:00:36.760 --> 0:00:41.199 talk about his personal and professional history as well as 0:00:41.240 --> 0:00:43.879 his run in with the unit Bomber. Right. Uh, so 0:00:44.200 --> 0:00:47.600 that figure, of course is James V. McConnell, the American psychologist. 0:00:48.040 --> 0:00:49.800 But if you listen to the last episode, as you 0:00:49.800 --> 0:00:52.360 should before this one, you already know that. So we're 0:00:52.360 --> 0:00:56.680 picking up after McConnell's initial research demonstrating in the nineteen 0:00:56.760 --> 0:01:01.600 fifties that despite conventional wisdom that in vertebrates could not learn, 0:01:01.800 --> 0:01:04.679 could not be trained through classical conditioning or any other 0:01:04.720 --> 0:01:08.200 kind of associate of learning. Uh. McConnell and colleagues did 0:01:08.240 --> 0:01:11.319 in fact demonstrate that that's not true, at least for planarians, 0:01:11.640 --> 0:01:15.679 these flatworms that that could be trained to react to 0:01:15.840 --> 0:01:18.920 something like a light stimulus. And we also discussed how 0:01:18.920 --> 0:01:21.640 it's just generally known to be true today that invertebrates 0:01:21.680 --> 0:01:24.039 can learn. The conventional wisdom at the time was wrong. 0:01:25.000 --> 0:01:27.759 But so to pick up with McConnell's career. After completing 0:01:27.800 --> 0:01:31.240 his graduate degree at the University of Texas, I almost 0:01:31.240 --> 0:01:35.039 said Jerry O'Connell, not Jerry O'Connell. James McConnell moved on 0:01:35.120 --> 0:01:38.160 to the University of Michigan, where he continued his research 0:01:38.160 --> 0:01:40.800 into flatworms. So the team that came to be known 0:01:40.840 --> 0:01:45.320 as the Pollinarian Research Group or pr G. So another 0:01:45.360 --> 0:01:49.040 piece of context for this research is a sort of 0:01:49.360 --> 0:01:54.560 quest for the holy Grail within twentieth century psychology and neuroscience, 0:01:54.640 --> 0:01:58.880 and this was the hunt for the elusive Ingram. It 0:01:59.000 --> 0:02:02.480 was believed by men in the mid century that a researcher, 0:02:02.800 --> 0:02:06.800 that the first researcher to actually pinpoint something known as 0:02:06.840 --> 0:02:10.240 the ingram, would receive the Nobel Prize for their work. 0:02:10.360 --> 0:02:13.360 But what was the ingram? The short version is that 0:02:13.440 --> 0:02:17.520 the ingram was believed to be the fundamental physical unit 0:02:17.600 --> 0:02:20.960 of memory represented in the body. In order for an 0:02:21.000 --> 0:02:25.080 animal to learn an association between two things, that memory 0:02:25.160 --> 0:02:28.480 has to be accompanied by some kind of physical change 0:02:28.600 --> 0:02:32.160 inside the body. But what is the fundamental unit of 0:02:32.200 --> 0:02:35.280 that change? Is it a structural change in the brain 0:02:35.360 --> 0:02:38.320 that can be located, or is it something else. So 0:02:38.400 --> 0:02:41.080 the idea is that you would see the physical evidence 0:02:41.120 --> 0:02:44.160 of learning and then potentially like that is physical evidence 0:02:44.200 --> 0:02:47.320 that could be then manipulated. Of course, yeah, it's sort 0:02:47.320 --> 0:02:50.360 of like searching for the atom. What the atom is 0:02:50.400 --> 0:02:53.640 to matter? The ingram would be to memory, what is 0:02:53.680 --> 0:02:57.480 the fundamental unit that that physically indicates in the body 0:02:57.520 --> 0:03:00.800 a memory has been formed. And of course motivation for 0:03:00.880 --> 0:03:04.839 studying whether simpler organisms like worms and other invertebrates could 0:03:04.840 --> 0:03:08.720 in fact learn associations through classical conditioning was that this 0:03:08.840 --> 0:03:12.600 might help move along the search for the ingram. If 0:03:12.600 --> 0:03:17.400 a biological phenomenon seems too complex to understand in one organism, 0:03:17.480 --> 0:03:19.360 you know, if you can't find it in a rabbit, 0:03:19.480 --> 0:03:22.079 everything is just too complicated. Maybe you can get a 0:03:22.080 --> 0:03:25.959 foothold to understanding by looking for analogous phenomena in simpler 0:03:26.040 --> 0:03:28.799 organisms and then build your way back up, and this 0:03:28.880 --> 0:03:30.880 is a sensible way to go about it, of course. 0:03:31.320 --> 0:03:33.600 Uh So, research in the middle of the twentieth century 0:03:33.600 --> 0:03:37.320 tried to locate the ingram two changes in a specific 0:03:37.360 --> 0:03:40.600 part of the brain and a rat, but these efforts failed. 0:03:40.960 --> 0:03:44.240 In fact, rat brain memory research he demonstrated that there 0:03:44.280 --> 0:03:48.280 was no one location or structure in which the fundamental 0:03:48.400 --> 0:03:51.840 unit of memory association was to be found. Instead, learning 0:03:51.840 --> 0:03:56.000 seemed to involve wide swaths of the rat cortex, and 0:03:56.080 --> 0:03:58.400 today we know that certain regions of the brain are 0:03:58.520 --> 0:04:02.600 especially important for memory. Is, for example, fear based conditioning, 0:04:02.680 --> 0:04:05.880 like if you condition somebody to respond to a stimulus 0:04:05.880 --> 0:04:09.400 through conditioning due to an electric shock. This seems to 0:04:09.560 --> 0:04:12.760 strongly implicate the amygdala, not just fear actually, but other 0:04:12.760 --> 0:04:15.960 types of emotional memory as well. I think, while memory 0:04:16.000 --> 0:04:20.239 of spatial locations and physical maps seems especially to implicate 0:04:20.320 --> 0:04:24.920 the hippocampus, but memories for complex actions maybe finding your 0:04:24.920 --> 0:04:28.040 way around a maze, as was often tried with rats, 0:04:28.360 --> 0:04:31.320 will involve lots of different parts of the brain at once, 0:04:31.360 --> 0:04:34.039 so you can't point to the memory in one specific 0:04:34.120 --> 0:04:37.359 part of the brain. It's using the whole brain. Basically, 0:04:37.640 --> 0:04:40.480 in the nineteen fifties. This wasn't yet clear it was. 0:04:40.640 --> 0:04:44.560 It was just clear that memory, contrary to the expectations 0:04:44.560 --> 0:04:48.799 of many psychologists, couldn't be located in one particular structure 0:04:48.880 --> 0:04:52.920 or single point physical change in the brain. And because 0:04:53.000 --> 0:04:56.800 of the failure of researchers to locate a structural ingram 0:04:56.839 --> 0:04:59.760 at a single point in the brain, some researchers began 0:04:59.800 --> 0:05:03.640 to turned to other explanations, and McConnell was one of them. 0:05:03.800 --> 0:05:08.760 McConnell wondered, what if memories were not stored exclusively in 0:05:08.880 --> 0:05:12.920 structures in the brain. Could you have memories in your hands, 0:05:13.080 --> 0:05:16.560 in your blood, in your guts. Was there a deeper 0:05:16.920 --> 0:05:21.560 chemical rather than structural basis for our memories? And here's 0:05:21.560 --> 0:05:25.800 where the Planarians again become an invaluable research tool in 0:05:25.880 --> 0:05:29.479 looking into could you have memories outside the brain? Could 0:05:29.520 --> 0:05:31.960 there be such a thing as a memory chemical or 0:05:32.000 --> 0:05:36.200 a memory molecule found throughout the body? And yeah, this 0:05:36.279 --> 0:05:39.200 we come back to the regenerative powers of the Planarian. 0:05:40.440 --> 0:05:43.040 We described this in the first episode as being something 0:05:43.080 --> 0:05:47.160 like The Sorcerer's Apprentice, the old Disney animation from Fantasia 0:05:47.240 --> 0:05:49.760 in which the uh what what is it? It's a 0:05:49.760 --> 0:05:52.400 broom that is brought to life to do a particular task, 0:05:52.760 --> 0:05:55.440 to carry water from a well. I think, and yeah, 0:05:55.520 --> 0:05:57.480 it was, it's a well. And then and then Nikki, 0:05:57.560 --> 0:06:00.280 the sorcerer's apprentice in this case uh In is up 0:06:00.320 --> 0:06:03.560 having to to destroy it, so he chops it into 0:06:03.600 --> 0:06:06.600 a million pieces with his axe, and then all those 0:06:06.640 --> 0:06:09.640 millions of pieces, each little sliver of the broom comes 0:06:09.680 --> 0:06:13.599 back to life and grows into a whole new fresh 0:06:13.640 --> 0:06:17.240 of broom with that walks around on two legs and 0:06:17.279 --> 0:06:19.919 carries buckets of water. Right, And this connects to the 0:06:19.960 --> 0:06:22.960 regenerative powers of planaria, because if you cut a planarian 0:06:23.040 --> 0:06:25.599 in half one of these flatworms, just chop it in 0:06:25.640 --> 0:06:29.400 half crosswise, separating the head from the tail. Each half 0:06:29.440 --> 0:06:32.440 of the worm would grow back the part it lost, 0:06:32.520 --> 0:06:36.479 So the decapitated head could regrow a tail, and the 0:06:36.560 --> 0:06:41.640 decapitated tail could regrow ahead, which means regrowing a brain. 0:06:42.279 --> 0:06:45.839 So McConnell's question was, if I condition a flat worm 0:06:46.000 --> 0:06:49.440 to learn something, maybe have a response to a stimulus 0:06:49.440 --> 0:06:52.240 like a flashing light, and then I cut it in half, 0:06:52.760 --> 0:06:56.800 which half of the worm will retain the response. If either, 0:06:57.200 --> 0:06:59.240 Now you might think the answer is obvious, right, Well, 0:06:59.240 --> 0:07:02.000 obviously the head half is where the brain is, so 0:07:02.080 --> 0:07:05.080 the head half will retain the conditioning if either side 0:07:05.120 --> 0:07:07.440 does and the tail half won't, Right that that seems 0:07:07.440 --> 0:07:10.440 like the obvious conclusion, Right, Yeah, that's what you would assume. 0:07:10.480 --> 0:07:13.400 That's what like a basic understanding of monster movies would 0:07:13.400 --> 0:07:17.000 have you assumed. Yes, McConnell found this was not exactly 0:07:17.040 --> 0:07:21.160 true in his experiments on freshwater flat worms called dogs 0:07:21.280 --> 0:07:25.160 a Dorado cephala. If you classically condition the worm to 0:07:25.240 --> 0:07:27.760 respond to a light and then you cut the flat 0:07:27.800 --> 0:07:32.040 worm into two halves, both halves retained the conditioning, and 0:07:32.080 --> 0:07:34.800 in a few cases the tail retained the conditioning more 0:07:34.960 --> 0:07:38.080 strongly than the head. So you could cut the head off, 0:07:38.600 --> 0:07:41.800 the tail would regrow ahead and it would still respond 0:07:42.240 --> 0:07:45.160 like the way it had learned to respond when it 0:07:45.200 --> 0:07:48.480 had its original head. So if all the learning was 0:07:48.520 --> 0:07:51.520 in the brain, how could that be possible? Right? This 0:07:51.560 --> 0:07:54.520 would seem to indicate that there's some sort of memory 0:07:54.600 --> 0:07:59.200 retention or memory storage going on within the body itself, right, 0:07:59.440 --> 0:08:01.720 And these was else were eventually published in the Journal 0:08:01.720 --> 0:08:05.720 of Comparative and Physiological Psychology. But then it gets even 0:08:05.800 --> 0:08:10.280 weirder because we're going to start playing flatworms Ship of Theseus? 0:08:10.400 --> 0:08:13.920 Uh so refresher on the Ship of Theseus? Thought experiment, Robert, 0:08:13.920 --> 0:08:15.560 do you want to do the honors here? Oh? Sure? 0:08:15.560 --> 0:08:18.400 This is the basic idea. If you you have this ship, 0:08:18.440 --> 0:08:22.400 for this legendary Ship of Theseus, you're celebrating it across 0:08:22.600 --> 0:08:25.320 the decades. Think about it. Is a ship that is 0:08:25.400 --> 0:08:28.080 docked for decades tends to fall apart piece by piece, 0:08:28.320 --> 0:08:31.520 so you replace it piece by piece. Eventually you reach 0:08:31.600 --> 0:08:34.800 the point where you have replaced every single piece of 0:08:34.840 --> 0:08:38.640 this vessel. The question is, is the Ship of Theseus 0:08:38.679 --> 0:08:42.400 any longer? The Ship of Theseus? Is it? It's it's 0:08:42.400 --> 0:08:44.680 not physically the same ship it was before, but it 0:08:44.800 --> 0:08:47.000 is the same shape. It's just all the pieces have 0:08:47.040 --> 0:08:49.640 been at this point replaced. Now, what if you in 0:08:49.720 --> 0:08:54.160 fact do this with flatworms since they can regenerate, And 0:08:54.200 --> 0:08:57.160 this is exactly what they tried. In a series of experiments, 0:08:57.559 --> 0:09:00.600 McConnell and the Planarian Research Group showed that if you 0:09:00.720 --> 0:09:03.040 cut a worm, like, for example, you cut a flat 0:09:03.040 --> 0:09:06.160 worm's head off after it's been conditioned and trained, so 0:09:06.200 --> 0:09:10.640 it has this memory response and then that tail regrows ahead, 0:09:11.200 --> 0:09:14.200 and then you cut the original tail off, so the 0:09:14.320 --> 0:09:18.880 regenerated head regrows a tail. Now you've got no original 0:09:19.000 --> 0:09:21.600 part of the worm left. So you've been through these 0:09:21.640 --> 0:09:25.319 multiple generations of cutting a worm apart and letting it regenerate. 0:09:25.760 --> 0:09:29.920 And yet their experiments found that some learning training memory 0:09:30.120 --> 0:09:34.079 was retained across the multiple generations where there was no 0:09:34.160 --> 0:09:37.760 original part of the worm left. Again, how would this 0:09:37.800 --> 0:09:41.480 be possible, Like, if memories are stored exclusively in the brain, 0:09:41.520 --> 0:09:45.120 how could a memory necessary to establish a conditioned response 0:09:45.559 --> 0:09:48.440 still operate within a tail that had its head cut off, 0:09:48.520 --> 0:09:51.079 or a segment of a worm grown from a segment 0:09:51.120 --> 0:09:53.199 of a worm grown from a segment of a worm 0:09:53.240 --> 0:09:56.240 that had been through the conditioning. And this led McConnell 0:09:56.280 --> 0:09:58.880 to suppose that he had evidence that memory may have 0:09:59.000 --> 0:10:03.440 strong chemical whole components. They're not limited to activity within 0:10:03.480 --> 0:10:08.080 the brain. There could be actual molecules of chemical memory 0:10:08.559 --> 0:10:12.000 coursing through the worm's body. Now, if this were true, 0:10:12.080 --> 0:10:16.160 this would of course be a revolutionary discovery right right right, 0:10:16.840 --> 0:10:20.160 because of course, and it would conceivably apply to other organisms. 0:10:20.200 --> 0:10:22.040 I mean, that's that's the thing. It might force us 0:10:22.080 --> 0:10:26.439 to completely rethink what we thought we knew about memory, right, 0:10:26.480 --> 0:10:28.840 and of course if it were true of flatworms, as possible, 0:10:28.880 --> 0:10:31.199 it would only be true of flatworms. But yeah, you 0:10:31.440 --> 0:10:33.680 don't know where else this would lead. Could it even 0:10:33.720 --> 0:10:36.480 be true of more complex animals. So it was this 0:10:36.559 --> 0:10:40.079 line of research about cut up flatworms retaining memories that 0:10:40.200 --> 0:10:42.960 led actually to the founding of the magazine we talked 0:10:42.960 --> 0:10:46.640 about in the last episode, The Worm Runners Digest. This 0:10:46.720 --> 0:10:52.959 was McConnell's magazine that quite strangely combined both real research 0:10:53.080 --> 0:10:57.080 on on planarians. It was like real flatworm research published 0:10:57.120 --> 0:11:02.840 alongside weird poems and and joke articles and satirical articles 0:11:02.840 --> 0:11:05.000 and stuff. It's such a weird title. The worm part 0:11:05.080 --> 0:11:09.760 clearly relates to the worm experiments, but it also brings 0:11:09.800 --> 0:11:12.160 to mind like blade Runner, except it's worm Runner. And 0:11:12.200 --> 0:11:14.760 it also makes me think of various Gary Larson far 0:11:14.840 --> 0:11:17.800 Side cartoons which a worm is perhaps, you know, wearing 0:11:17.800 --> 0:11:20.120 sweatpants and linn running. That's good, But the joke and 0:11:20.200 --> 0:11:22.600 title in the title is actually a reference to like 0:11:23.080 --> 0:11:26.200 common terms used by psychologists of this period, lots of 0:11:26.240 --> 0:11:31.040 research about learning and memory involves rats and mazes, and 0:11:31.120 --> 0:11:34.320 so researchers who did this kind of work referred to 0:11:34.360 --> 0:11:38.720 themselves jokingly in the nineteen fifties as rat runners. McConnell's 0:11:38.800 --> 0:11:44.400 variation is self explanatory. Jerry the worm runner. Okay, not Jerry, Jarry, 0:11:44.520 --> 0:11:50.000 Jerry O'Connell, James Ry myself there, James the worm runner then, 0:11:50.679 --> 0:11:52.800 but yeah, actually so coming back. So this led to 0:11:52.800 --> 0:11:55.640 the founding of this strange magazine that he became very 0:11:55.640 --> 0:11:59.080 well known for. The story has summarized by Larry Stern, 0:11:59.200 --> 0:12:01.360 and I mentioned and several sources at the beginning of 0:12:01.400 --> 0:12:03.760 the last episode. We're still referring to those sources in 0:12:03.800 --> 0:12:06.640 this episode. One was an article by Larry Stern that 0:12:06.679 --> 0:12:08.599 that talked about the founding of this magazine. So in 0:12:08.679 --> 0:12:13.000 nineteen nine, McConnell presented some of this work, uh, this 0:12:13.040 --> 0:12:17.400 work about chopping up flatworms and then supposedly retaining memories 0:12:17.640 --> 0:12:20.680 to an annual convention of the American Psychological Association the 0:12:20.720 --> 0:12:23.440 a p A. And this included results collected by a 0:12:23.480 --> 0:12:27.200 member of the Planarian Research Group named Riva Jacobson. And 0:12:27.240 --> 0:12:30.240 again this research showed that not only could a decapitated 0:12:30.240 --> 0:12:33.760 flatworm retain associate of learning, but essentially the ship of 0:12:33.800 --> 0:12:37.440 theseus flatworm containing no tissue of the original worm could 0:12:37.480 --> 0:12:41.480 also retain learning, and after the presentation, Newsweek published an 0:12:41.559 --> 0:12:44.959 article summarizing the research. This led to a huge surge 0:12:45.000 --> 0:12:49.160 of popular interest in McConnell's work, and so Larry Stern 0:12:49.160 --> 0:12:53.319 writes quote. Shortly after the Newsweek coverage, McConnell was inundated 0:12:53.360 --> 0:12:56.280 with letters from high school students from around the country 0:12:56.679 --> 0:12:59.840 asking where they could obtain worms for their projects and 0:13:00.000 --> 0:13:02.480 how they should go about caring for and training them. 0:13:02.520 --> 0:13:05.400 Some students, according to McConnell, demanded that he sent them 0:13:05.400 --> 0:13:08.280 a few hundred trained worms at once, as their projects 0:13:08.280 --> 0:13:11.840 were due within days. It sounds a little familiar, right, 0:13:12.720 --> 0:13:15.760 Students don't do things like this, but McConnell did want 0:13:15.760 --> 0:13:18.679 to help students conduct their own flatworm research. I get 0:13:18.679 --> 0:13:21.360 the feeling he was into this idea, but he realized 0:13:21.440 --> 0:13:23.200 very quickly that it didn't make sense to try to 0:13:23.240 --> 0:13:27.080 respond to each letter individually, so instead he decided to 0:13:27.200 --> 0:13:31.000 publish a manual on how to replicate the experiments performed 0:13:31.040 --> 0:13:34.120 by the PRG, and he titled this document The Worm 0:13:34.200 --> 0:13:39.320 Runners Digest. However, after publishing this manual under that title, 0:13:39.640 --> 0:13:43.400 McConnell started getting submissions to appear in future issues. So 0:13:43.800 --> 0:13:47.400 he began publishing this so called journal on a regular basis, again, 0:13:47.679 --> 0:13:52.400 including both real research and psychological in jokes, cartoons, poems, 0:13:52.400 --> 0:13:54.640 and all that kind of stuff interwriting. So it's kind 0:13:54.640 --> 0:13:59.559 of accidentally became a continuing publication. Yeah. Now, as you 0:13:59.600 --> 0:14:02.600 can magine, some people didn't take kindly to this mix 0:14:02.640 --> 0:14:06.160 of subject matter. In nineteen sixty four, after some readers 0:14:06.200 --> 0:14:08.839 complained that they couldn't tell the real research from the 0:14:08.920 --> 0:14:12.720 jokes and the satire, they started publishing the satirical elements 0:14:12.840 --> 0:14:15.320 upside down in the back half of the journal. So 0:14:15.440 --> 0:14:18.280 there was some attempt there to clear up the confusion. 0:14:18.360 --> 0:14:20.440 But I think for a lot of scientists the pure 0:14:20.640 --> 0:14:23.800 proximity of the different material was was a problem no 0:14:23.840 --> 0:14:26.880 matter how clear the division. Well, I think that's understandable. 0:14:26.960 --> 0:14:30.080 We talked before about the Ignoble Prizes, for instance, about 0:14:30.080 --> 0:14:33.240 most of the individuals involved and honored by these prizes 0:14:33.440 --> 0:14:37.600 that celebrate, you know, scientific studies that are legitimate scientific studies, 0:14:37.600 --> 0:14:41.240 but that are on some level humorous or amusing. But 0:14:41.320 --> 0:14:44.600 you still have some individuals in the scientific world who 0:14:44.920 --> 0:14:47.680 do not see the value of that. So if they're 0:14:48.040 --> 0:14:50.720 so if feathers are ever ruffled by the ignoble prizes, 0:14:50.920 --> 0:14:53.920 obviously something like this would ruffle feathers as well. Yes, 0:14:54.520 --> 0:14:57.120 uh so, Then in nineteen sixty seven there came another 0:14:57.240 --> 0:14:59.880 split where the serious half of the journal was just 0:15:00.120 --> 0:15:03.800 formally cleaved and renamed, in fact cloven in half like 0:15:03.840 --> 0:15:08.520 a flatworm, uh, chopped right off, decapitated. The serious half 0:15:08.680 --> 0:15:12.280 was renamed the Journal of Biological Psychology, and the worm 0:15:12.320 --> 0:15:15.360 runners Digest became the soul Haven of Humor, and it 0:15:15.440 --> 0:15:18.720 continued publishing that way until all Right, on that note, 0:15:18.720 --> 0:15:20.400 we're going to take a quick break, but we will 0:15:20.440 --> 0:15:26.240 be right back. Than alright, we're back, alright, So to 0:15:26.360 --> 0:15:30.200 jump back into the progression of James McConnell's research, we're 0:15:30.240 --> 0:15:32.720 we're brought back to this question of a non brain 0:15:33.040 --> 0:15:37.520 chemical basis for memory. Couldn't memory, or at least some memory, 0:15:37.680 --> 0:15:41.920 some types of memories be stored chemically rather than structurally 0:15:42.120 --> 0:15:45.760 dispersed in the body in molecules, And here's where we 0:15:45.800 --> 0:15:49.240 get to the cannibalism. So, if there were in fact 0:15:49.400 --> 0:15:53.400 molecules within an animal representing some kind of chemical memory, 0:15:53.960 --> 0:15:57.360 such as memory of how to navigate a maze, could 0:15:57.360 --> 0:16:01.200 this be demonstrated? Could those molecules be shared from one 0:16:01.320 --> 0:16:04.800 animal to another? And this makes sense. That's what creatures do. 0:16:04.960 --> 0:16:07.880 They take molecules from each other, from other organisms and 0:16:07.880 --> 0:16:11.160 put them into themselves. Sure, we absorbed the molecules existing 0:16:11.160 --> 0:16:15.320 in other organisms for nutrition. Uh, so maybe you could 0:16:15.360 --> 0:16:19.800 molecules be absorbed from one organism to another four memory transfer. 0:16:20.280 --> 0:16:22.680 So the first method they tried, uh and this is 0:16:22.960 --> 0:16:26.200 based on the reporting of one of those Larry Stern articles. 0:16:26.480 --> 0:16:29.080 The first method they tried was to splice the head 0:16:29.120 --> 0:16:32.760 of a conditioned worm onto the tail of an unconditioned 0:16:32.800 --> 0:16:34.920 worm to see if it would share molecules right, to 0:16:34.960 --> 0:16:38.880 force them to exchange the alleged memory molecules. But the 0:16:38.920 --> 0:16:41.880 transplant did not work. The head would not stay attached. 0:16:42.360 --> 0:16:46.480 Then they tried to liquefy fully conditioned flat worms and 0:16:46.600 --> 0:16:50.680 inject their juice into untrained worms, but this was also difficult. 0:16:51.200 --> 0:16:54.480 The planarians were too small to be injected basically, and 0:16:54.520 --> 0:16:58.480 sometimes they exploded when injected. In Larry Stern's words quote 0:16:58.520 --> 0:17:00.960 it was like trying to impay all a prune with 0:17:01.000 --> 0:17:04.480 a javelin a lot of horrific things done to to 0:17:04.640 --> 0:17:07.399 planarians in these experiments. I guess they are a simple 0:17:07.520 --> 0:17:11.320 enough organisms that we have to be so upset about them, 0:17:11.359 --> 0:17:15.000 I guess, But it's still one can't help it. Pause 0:17:15.040 --> 0:17:17.680 a little on some of these, right, some of the grinding, Yeah, 0:17:17.720 --> 0:17:23.199 the sauce, the gravy, the flatworm sauce. So how do 0:17:23.240 --> 0:17:26.359 you get those hypothetical memory molecules in there? If you 0:17:26.400 --> 0:17:29.800 can't inject them, you can't transplant ahead on. So the 0:17:29.840 --> 0:17:31.600 next route they tried, and this was in the year 0:17:31.720 --> 0:17:36.119 nineteen sixty, was experimental planarian cannibalism. This would be the 0:17:36.160 --> 0:17:39.040 old fashioned way of getting molecules from one organism into 0:17:39.080 --> 0:17:41.520 the other. Sure, so apparently the idea came from a 0:17:41.560 --> 0:17:46.000 flatworm researcher named Jay Boyd Best who communicated to McConnell 0:17:46.320 --> 0:17:49.440 about the fact that one particular species of planarian was 0:17:49.560 --> 0:17:53.679 known for cannibalistic behavior. So here's the answer. You train 0:17:53.760 --> 0:17:56.679 the worms to respond to to a maze or to 0:17:56.720 --> 0:17:59.600 the light, whatever the conditioning stimulus is, and then they 0:17:59.720 --> 0:18:02.600 learn the conditioning and then you grind them up into 0:18:02.600 --> 0:18:05.480 worm gravy, and then you feed the worm gravy to 0:18:05.600 --> 0:18:10.359 the untrained naive worms, and you see what happens, and astonishingly, 0:18:10.560 --> 0:18:14.720 their early experiments with this method looked very promising, including 0:18:14.760 --> 0:18:18.359 a number of early replication attempts with blinding procedures to 0:18:18.400 --> 0:18:23.000 remove the possibility of experiment or bias, supposedly confirming their 0:18:23.000 --> 0:18:27.600 early results. So, if it were true that memory molecules 0:18:27.600 --> 0:18:32.159 are being exchanged through this strange cannibalistic ritual, could I, 0:18:32.400 --> 0:18:35.480 you know, with this extend to humans? Could could I 0:18:35.560 --> 0:18:39.480 drink your flesh and gain your memories? And how was 0:18:39.520 --> 0:18:42.880 it happening? What was the chemical basis here? So one 0:18:42.960 --> 0:18:45.840 interesting line of reasoning here followed from the still somewhat 0:18:45.920 --> 0:18:51.280 recent discoveries about genetic information being stored in and mediated 0:18:51.320 --> 0:18:55.240 by nucleic acids DNA and RNA. Remember, you know, we're 0:18:55.240 --> 0:18:57.560 not too far from from the discovery of the double 0:18:57.600 --> 0:19:02.480 helix here. So if DNA and RNA could be involved 0:19:02.520 --> 0:19:08.080 in an information management process passing genetic information across generations 0:19:08.119 --> 0:19:11.720 from parents to offspring, could the same molecules also in 0:19:11.880 --> 0:19:15.920 code and mediate other types of information? I mean information 0:19:16.040 --> 0:19:20.840 is in the DNA. So specifically, could the information content 0:19:20.920 --> 0:19:26.119 of memories somehow be coded into DNA or RNA and 0:19:26.160 --> 0:19:30.600 then dispersed through the body, but also transferred from one 0:19:30.640 --> 0:19:33.440 body to another. And so this is the line they took. 0:19:33.680 --> 0:19:37.800 McConnell and his team conducted experiments and published results that 0:19:37.920 --> 0:19:40.119 seemed to back up the idea, at least for a while, 0:19:40.560 --> 0:19:44.199 that RNA played some important role in facilitating memory, and 0:19:44.200 --> 0:19:48.400 that RNA could be used to chemically inoculate naive worms 0:19:48.440 --> 0:19:53.159 with the memory associations of their more worldly predecessors. And again, 0:19:53.280 --> 0:19:56.240 just consider how revolutionary this would be if it turned 0:19:56.240 --> 0:19:58.880 out to be true. You'd be forced to wonder how 0:19:58.920 --> 0:20:02.000 far the principle could be taken. Did this only apply 0:20:02.080 --> 0:20:05.720 to planarians or did it extend to other more complex animals. 0:20:06.000 --> 0:20:09.399 Would there be ways in which humans could undergo chemical learning? 0:20:09.600 --> 0:20:11.960 Could you train the mind in some way with an 0:20:11.960 --> 0:20:15.160 injection alone, or even a pill? Even if it only 0:20:15.200 --> 0:20:18.879 worked for like broad associative learning such as you know, 0:20:18.920 --> 0:20:21.199 the kind of things you get through classical conditioning with 0:20:21.240 --> 0:20:24.440 an electric shock and a single stimulus, you could still 0:20:24.480 --> 0:20:28.560 possibly imagine profound benefits. Just one idea comes to mind, like, 0:20:28.920 --> 0:20:31.720 say you're struggling with a drug addiction. Could you seek 0:20:31.760 --> 0:20:35.879 out an injection of of memory molecules to establish a 0:20:35.920 --> 0:20:39.040 strong averse reaction to your drug of choice such that 0:20:39.080 --> 0:20:41.600 you wouldn't want to take it anymore. Yeah, Or to 0:20:41.640 --> 0:20:44.600 get into some of the behavioral his ideas that we 0:20:44.640 --> 0:20:48.040 discussed in the first episode, some of those ideas that 0:20:47.560 --> 0:20:52.080 that that McConnell's very outspoken about it, even later in life. 0:20:52.920 --> 0:20:55.040 You could have some sort of a cocktail that could 0:20:55.080 --> 0:20:58.800 be injected into an individual that had a history of 0:20:59.000 --> 0:21:03.080 violence and history of of you know, breaking the law 0:21:03.119 --> 0:21:06.320 and rebelling against authority figures, and you could can potentially 0:21:06.680 --> 0:21:09.400 fix them with this injection. Yeah. And of course there 0:21:09.480 --> 0:21:13.000 you get into the more nefarious possible thing, Like you 0:21:13.000 --> 0:21:18.159 can probably instantaneously imagine so many horrible, insidious uses for 0:21:18.240 --> 0:21:21.880 injectable conditioning if such a thing were possible. Oh yes, 0:21:22.000 --> 0:21:25.480 I mean, as with any science, many many fabulous uses 0:21:25.520 --> 0:21:28.960 come to mind, but so many nightmares as well. But 0:21:29.240 --> 0:21:31.080 we should stop and be real for a second here, 0:21:31.160 --> 0:21:33.879 that even if these findings had turned out to be 0:21:33.960 --> 0:21:36.720 totally solid for planaria and more on, that in a moment, 0:21:37.160 --> 0:21:40.240 we should know better than to freely extrapolate from worms 0:21:40.280 --> 0:21:41.960 to humans. I think this is one of the most 0:21:42.000 --> 0:21:46.760 classic traps that people fall into and interpreting biological research. 0:21:47.119 --> 0:21:50.200 I'd say more often as people extrapolating from like rats 0:21:50.240 --> 0:21:52.960 to humans. But this isn't a much larger jump. This 0:21:53.040 --> 0:21:55.800 isn't even a vertebrate animal. Yeah, I mean, you can't help. 0:21:56.160 --> 0:21:58.320 I often find that I can't help, but but at 0:21:58.400 --> 0:22:00.600 least think about that on some when I read a 0:22:00.600 --> 0:22:03.680 science headline, I can't help it. Put myself into into 0:22:03.720 --> 0:22:06.439 it somehow and imagine myself as the creature, right, And 0:22:06.600 --> 0:22:08.679 it's often, I mean, it's just done right there in 0:22:08.680 --> 0:22:13.520 the press. Again, it's fine to wonder about what possibilities 0:22:13.640 --> 0:22:17.480 could be implied by studies in rats for humans, but 0:22:17.800 --> 0:22:20.479 you can't just, you know, conclude from one to another. 0:22:20.800 --> 0:22:24.359 We can't help but anthropomorphize virtually any creature, and if 0:22:24.359 --> 0:22:26.280 that creatures in a study, we're also going to end 0:22:26.320 --> 0:22:30.879 up anthropomorphizing that as well. But James McConnell, true to form, 0:22:31.040 --> 0:22:32.960 as we know from the last episode, was not one 0:22:33.000 --> 0:22:36.439 to be shy or cautious about interpreting his findings. He 0:22:36.680 --> 0:22:41.080 loudly proclaimed them to the public, advertising his results on 0:22:41.119 --> 0:22:45.720 TV programs. He apparently embraced the nickname mccannibal uh, and 0:22:45.920 --> 0:22:50.280 he predicted an era of memory pills like we just discussed, 0:22:50.640 --> 0:22:52.679 So you might be thinking, like, wait a minute, he 0:22:52.760 --> 0:22:57.040 should know better than to extrapolate from planarian even if 0:22:57.040 --> 0:23:01.520 you assume the planarian research to be solid and will 0:23:01.520 --> 0:23:04.240 introduce some caveats to that. But even if you did 0:23:04.240 --> 0:23:06.639 assume that, how could you jump from that to human 0:23:06.760 --> 0:23:10.160 memory pills? That seems like a you know, a leap 0:23:10.240 --> 0:23:13.800 of miles of assumptions. Yeah, very much though, And it 0:23:13.880 --> 0:23:16.159 does seem from from what I was reading, especially in 0:23:16.240 --> 0:23:20.800 Rilling's paper about McConnell, that it seemed like to him 0:23:20.920 --> 0:23:23.600