1 00:00:05,760 --> 00:00:07,560 Speaker 1: Hey, you welcome to stuff to blow your mind. My 2 00:00:07,640 --> 00:00:10,479 Speaker 1: name is Robert Lamb and I'm Joe McCormick. In It's Saturday. 3 00:00:10,520 --> 00:00:12,879 Speaker 1: Time to go into the old vault? Robert, is this 4 00:00:12,920 --> 00:00:15,960 Speaker 1: one where I did the Sean Connery voice? Now, I'm 5 00:00:16,079 --> 00:00:21,279 Speaker 1: just remembering in this moment, remember, oh no, are we were? Okay? Well, 6 00:00:21,320 --> 00:00:23,600 Speaker 1: I We'll just have to deal with it. This originally 7 00:00:23,640 --> 00:00:28,960 Speaker 1: published July, and this is an episode we did about neuroplasticity. Now, 8 00:00:29,040 --> 00:00:31,560 Speaker 1: we were just saying before we started recording this intro, 9 00:00:32,240 --> 00:00:35,839 Speaker 1: uh that after having done all the stuff on psychedelics 10 00:00:35,880 --> 00:00:38,640 Speaker 1: we just went through we we we may, we may 11 00:00:38,680 --> 00:00:42,279 Speaker 1: approach this subject to it from a kind of different angle. Now, 12 00:00:42,320 --> 00:00:44,320 Speaker 1: I wonder if I don't know, if you listen to 13 00:00:44,360 --> 00:00:46,199 Speaker 1: this episode and you want to hear you want to 14 00:00:46,200 --> 00:00:49,559 Speaker 1: hear us revisit the topic with with new wisdom let 15 00:00:49,640 --> 00:00:51,440 Speaker 1: us know. Yeah, I feel like it would this would 16 00:00:51,440 --> 00:00:53,760 Speaker 1: have been a different episode if we had recorded it 17 00:00:53,840 --> 00:00:57,240 Speaker 1: after the psychedelic episodes. But I still think it holds 18 00:00:57,320 --> 00:01:01,040 Speaker 1: up as a solid vault entry. So dr jessup, do 19 00:01:01,080 --> 00:01:03,840 Speaker 1: you expect me to talk? Oh this this isn't a 20 00:01:03,960 --> 00:01:10,160 Speaker 1: standard interrogation. Inject him watch this now, poison truth Serer. 21 00:01:10,600 --> 00:01:14,720 Speaker 1: None of the above. No, this is something far more experimental. 22 00:01:15,040 --> 00:01:18,119 Speaker 1: But perhaps a notorious secret agents such as yourself has 23 00:01:18,160 --> 00:01:25,319 Speaker 1: heard of induced neuroplasticity. What you're talking of experimental neurotherapy drugs, 24 00:01:25,360 --> 00:01:30,200 Speaker 1: your math? Neuroplasticity is far more than that. Yes, yes, this, 25 00:01:30,200 --> 00:01:34,000 Speaker 1: this sort of treatment will soon revolutionize the way we 26 00:01:34,040 --> 00:01:38,120 Speaker 1: deal with addictions and brain disease. It will allow adults 27 00:01:38,160 --> 00:01:40,880 Speaker 1: of any age to learn new languages with the aptitude 28 00:01:40,880 --> 00:01:43,640 Speaker 1: of a young child. But that's not why I've injected 29 00:01:43,720 --> 00:01:48,680 Speaker 1: you with it. No, we've We've romanticized neuroplasticity. You see, 30 00:01:48,680 --> 00:01:53,000 Speaker 1: we forget the importance of neuro stability. As children, we 31 00:01:53,080 --> 00:01:57,080 Speaker 1: have an amazing ability to adapt to any environment, any language. 32 00:01:57,120 --> 00:01:59,920 Speaker 1: Were open to the world. We're also open to try. 33 00:02:00,800 --> 00:02:03,480 Speaker 1: But then everything has to settle. We put aside those 34 00:02:03,560 --> 00:02:08,320 Speaker 1: childish things and we become bia then doctors, secret agents. 35 00:02:08,800 --> 00:02:10,800 Speaker 1: What do you want from me? Why? I want to 36 00:02:10,919 --> 00:02:15,280 Speaker 1: change your life? Hans Roll the film? Wait, what what 37 00:02:15,360 --> 00:02:20,239 Speaker 1: are you showing me? Joseph are YouTube playlist, Oh please, 38 00:02:20,880 --> 00:02:26,120 Speaker 1: hours upon hours of let's call it informative content from 39 00:02:26,160 --> 00:02:31,040 Speaker 1: some of the platforms. Leading personality No, not dish influencers. 40 00:02:31,919 --> 00:02:37,120 Speaker 1: I'll tell you anything for medians, no commentators, unboxes. No. 41 00:02:42,520 --> 00:02:45,400 Speaker 1: Welcome to Stuff to Blow your Mind from How Stuff 42 00:02:45,400 --> 00:02:54,120 Speaker 1: Works dot com. Hey, welcome to Stuff to Blow your Mind. 43 00:02:54,160 --> 00:02:56,600 Speaker 1: My name is Robert Lamb and I'm Joe McCormick. And 44 00:02:56,680 --> 00:02:59,440 Speaker 1: today we're gonna be talking about another topic that's sort 45 00:02:59,440 --> 00:03:02,000 Speaker 1: of a fall up from Robert's visit this year to 46 00:03:02,040 --> 00:03:06,119 Speaker 1: the World Science Festival. We're gonna be talking about neuroplasticity. 47 00:03:06,200 --> 00:03:09,880 Speaker 1: That's right. This, uh, this particular panel that that I attended, 48 00:03:09,919 --> 00:03:12,200 Speaker 1: and this one is also available online. Will make sure 49 00:03:12,200 --> 00:03:15,080 Speaker 1: there's a link to the YouTube video on the landing 50 00:03:15,080 --> 00:03:17,320 Speaker 1: page for this episode Acceptable in your Mind dot com. Uh. 51 00:03:17,400 --> 00:03:20,079 Speaker 1: The particular panel was called Nuts and Bolts of Better Brains. 52 00:03:20,480 --> 00:03:25,480 Speaker 1: It was hosted by Guy mccon, a neurosurgeon, neuroscientist, Alvero 53 00:03:25,600 --> 00:03:31,040 Speaker 1: pascal Leoni, neuroscientist, uh Nim Tottenham, developmental law psychologist, and 54 00:03:31,080 --> 00:03:35,120 Speaker 1: Carlas Shots, a neuroscientist, and they discussed neuroplasticity, which is 55 00:03:35,160 --> 00:03:37,480 Speaker 1: something that we've we've touched on on the show before 56 00:03:37,520 --> 00:03:39,240 Speaker 1: and I think a lot of people have kind of 57 00:03:39,280 --> 00:03:43,760 Speaker 1: a general concept of yeah, neuroplasticity is one of those 58 00:03:43,800 --> 00:03:46,720 Speaker 1: words that I think has suffered a lot of abuse 59 00:03:47,000 --> 00:03:51,320 Speaker 1: in the press um because I mean, there are words 60 00:03:51,360 --> 00:03:54,280 Speaker 1: that have a good meaning in science, and there's nothing 61 00:03:54,320 --> 00:03:59,280 Speaker 1: wrong with the concept itself. But in today's neuroscience, neuroplasticity 62 00:03:59,320 --> 00:04:00,800 Speaker 1: does have a me ng and it does have a 63 00:04:00,880 --> 00:04:04,840 Speaker 1: useful meaning. But you see it in a lot of 64 00:04:05,600 --> 00:04:09,400 Speaker 1: hype and bs on the internet. Yeah, Like I noticed, 65 00:04:09,400 --> 00:04:11,680 Speaker 1: when when you do a search for neuroplasticity you want 66 00:04:11,680 --> 00:04:15,040 Speaker 1: to read things about it, you get mostly content at 67 00:04:15,080 --> 00:04:19,480 Speaker 1: one of two levels. Either content for experts and neuroscientists, 68 00:04:19,520 --> 00:04:22,719 Speaker 1: like actual scientific literature that the average reader can't penetrate, 69 00:04:23,080 --> 00:04:26,039 Speaker 1: and then you get also a whole lot of hype 70 00:04:26,080 --> 00:04:29,359 Speaker 1: and bs that is telling you about I don't know, 71 00:04:29,400 --> 00:04:31,720 Speaker 1: about how you're going to revolutionize your brain and you'll 72 00:04:31,760 --> 00:04:34,279 Speaker 1: become like a child again and become a master of 73 00:04:34,320 --> 00:04:36,800 Speaker 1: your own abilities. Yeah. I mean, it's already become something 74 00:04:36,800 --> 00:04:39,800 Speaker 1: of a buzzword, for instance, with with certain uh like 75 00:04:39,839 --> 00:04:45,560 Speaker 1: supplement manufacturers and take this neuroplasticity vitamin. Yeah, okay, thanks, 76 00:04:46,240 --> 00:04:49,359 Speaker 1: But but the neuroplasticity is a real thing. It is 77 00:04:49,480 --> 00:04:51,960 Speaker 1: you can think of it simply as the brain's ability 78 00:04:52,000 --> 00:04:56,719 Speaker 1: to adapt and humans most incredible powers of neuroplasticity, especially 79 00:04:56,800 --> 00:05:00,640 Speaker 1: during the so called critical periods of early childhood. Yeah. 80 00:05:00,680 --> 00:05:02,719 Speaker 1: One of the things to think about this kind of 81 00:05:02,760 --> 00:05:09,520 Speaker 1: weird is um how well humans adapt to such different 82 00:05:09,760 --> 00:05:15,400 Speaker 1: life conditions. Like if you take most animals out of 83 00:05:15,440 --> 00:05:18,680 Speaker 1: the environment and condition conditions that they're best adapted to, 84 00:05:19,200 --> 00:05:22,359 Speaker 1: they don't do very well. There are some exceptions, but 85 00:05:22,440 --> 00:05:25,000 Speaker 1: most of the time an animal has evolved to have 86 00:05:25,080 --> 00:05:29,560 Speaker 1: certain instincts. It's got sort of like pretty hardwired behaviors. 87 00:05:29,680 --> 00:05:32,279 Speaker 1: It can live, you know, it can be born where 88 00:05:32,360 --> 00:05:35,400 Speaker 1: it is supposed to be born and live encountering the 89 00:05:35,480 --> 00:05:38,599 Speaker 1: kind of stimuli it would normally encounter, and you know, 90 00:05:38,800 --> 00:05:40,960 Speaker 1: it can do its thing that nature has shaped it for. 91 00:05:41,240 --> 00:05:44,719 Speaker 1: But humans can do all kinds of stuff. We can 92 00:05:44,760 --> 00:05:47,000 Speaker 1: live in the snow, we can live in the desert, 93 00:05:47,120 --> 00:05:50,600 Speaker 1: we can live in cities, we can live in it planes, 94 00:05:50,720 --> 00:05:53,280 Speaker 1: we can be farmers, we can be doctors. We can 95 00:05:53,320 --> 00:05:56,480 Speaker 1: do so many different kinds of things with our brains. 96 00:05:56,800 --> 00:06:00,000 Speaker 1: And there are no other animals like this really. Yeah. 97 00:06:00,080 --> 00:06:01,960 Speaker 1: The in the talk, they brought up the example of 98 00:06:02,000 --> 00:06:04,599 Speaker 1: the logerhead turtle as an example of a creature that 99 00:06:04,720 --> 00:06:08,800 Speaker 1: is not a paragon of neuroplasticity but neuro stability. A 100 00:06:08,800 --> 00:06:12,480 Speaker 1: creature that, upon birth is just ready to go and 101 00:06:12,480 --> 00:06:15,840 Speaker 1: do a very specific thing exceedingly well in a very 102 00:06:15,880 --> 00:06:19,479 Speaker 1: specific environment. But if you put some major obstacles in 103 00:06:19,520 --> 00:06:22,760 Speaker 1: that turtle's way, the turtle probably would not find a 104 00:06:22,800 --> 00:06:26,040 Speaker 1: way to adapt to those obstacles and survive around them. 105 00:06:26,040 --> 00:06:28,880 Speaker 1: It would probably just not survive to adulthood, right, I mean, 106 00:06:29,000 --> 00:06:30,880 Speaker 1: the the turtle is a good example of that, because, 107 00:06:30,920 --> 00:06:33,360 Speaker 1: I mean, with with with various sea turtles, we've seen 108 00:06:33,360 --> 00:06:37,479 Speaker 1: examples of how just artificial lighting can screw up a 109 00:06:37,600 --> 00:06:41,560 Speaker 1: very particular approach to going about its life cycle. Yeah, 110 00:06:41,600 --> 00:06:44,520 Speaker 1: but so your brain. One of the reasons your brain 111 00:06:44,600 --> 00:06:47,839 Speaker 1: is so powerful compared to the brains of animals is 112 00:06:47,920 --> 00:06:51,240 Speaker 1: that it can be adapted to so many different scenarios 113 00:06:51,240 --> 00:06:54,680 Speaker 1: and so many different types of tasks depending on what 114 00:06:54,800 --> 00:06:59,640 Speaker 1: sorts of environments you're exposed to when you're very young. Yeah, languages, 115 00:06:59,680 --> 00:07:01,680 Speaker 1: of course one of the great examples. And I think 116 00:07:01,680 --> 00:07:05,400 Speaker 1: everyone has at least some awareness of this. Certainly, anybody 117 00:07:05,400 --> 00:07:07,520 Speaker 1: out there who's a parent has has read about this 118 00:07:07,640 --> 00:07:10,480 Speaker 1: or experience this with their own children. Is that during 119 00:07:10,680 --> 00:07:14,720 Speaker 1: certain critical periods, they have an amazing ability to not 120 00:07:14,800 --> 00:07:17,200 Speaker 1: only pick up a language, but to just perfectly pick 121 00:07:17,200 --> 00:07:20,440 Speaker 1: it up, to just breathe it in and and and 122 00:07:20,480 --> 00:07:23,680 Speaker 1: become fluent in it without with without any of the 123 00:07:23,800 --> 00:07:28,480 Speaker 1: challenges that are generally encountered by adults trying to learn 124 00:07:28,480 --> 00:07:30,320 Speaker 1: a second language. I mean, one of the ways that 125 00:07:30,400 --> 00:07:33,840 Speaker 1: it's often put is that with great effort, and adult 126 00:07:34,280 --> 00:07:36,880 Speaker 1: can learn to speak a language they don't already speak, 127 00:07:36,920 --> 00:07:39,240 Speaker 1: but they will pretty much always speak it with an accent. 128 00:07:39,920 --> 00:07:42,360 Speaker 1: Children can learn to speak all kinds of and can 129 00:07:42,440 --> 00:07:44,640 Speaker 1: learn to speak multiple languages at the same time, and 130 00:07:44,680 --> 00:07:47,440 Speaker 1: can generally learn to speak them without an accent. Right. 131 00:07:47,560 --> 00:07:49,120 Speaker 1: But then of course it goes beyond this too, because 132 00:07:49,240 --> 00:07:51,680 Speaker 1: there there's so many other things that are being absorbed 133 00:07:52,000 --> 00:07:55,960 Speaker 1: during childhood. You know, the social norms, cultural norms, just 134 00:07:56,200 --> 00:07:59,680 Speaker 1: how one interacts with your environment, and that has enabled 135 00:08:00,040 --> 00:08:03,320 Speaker 1: humans to thrive all over the world, you know, obviously 136 00:08:03,360 --> 00:08:08,440 Speaker 1: with technological aids in many cases, but still it it 137 00:08:08,680 --> 00:08:12,320 Speaker 1: underlies the diversity and success of our species. Then again, 138 00:08:12,520 --> 00:08:15,520 Speaker 1: there are some reasons to think that you don't want 139 00:08:15,560 --> 00:08:19,280 Speaker 1: the brain to be sort of infinitely plastic right, Because 140 00:08:19,480 --> 00:08:23,040 Speaker 1: if we consider plasticity the ability of the brain to 141 00:08:23,160 --> 00:08:26,320 Speaker 1: adapt to new scenarios and change itself to work better, 142 00:08:26,920 --> 00:08:29,040 Speaker 1: you also need cases where the brain knows what to 143 00:08:29,120 --> 00:08:32,320 Speaker 1: do and does it instead of keeps being influenced and 144 00:08:32,400 --> 00:08:35,120 Speaker 1: changing right right, and knows where to where to where 145 00:08:35,120 --> 00:08:38,079 Speaker 1: to stop. You know what, what avenues to stop exploring 146 00:08:38,400 --> 00:08:41,319 Speaker 1: because basically what happens is their neural circuitry branches out 147 00:08:41,400 --> 00:08:44,880 Speaker 1: to master the skills necessary for survival. And then, uh, 148 00:08:44,920 --> 00:08:46,760 Speaker 1: and then after it does this, after you know, some 149 00:08:46,800 --> 00:08:49,440 Speaker 1: of the branches have been prune back. Uh. You can 150 00:08:49,480 --> 00:08:50,880 Speaker 1: think of it like a you know, like one of 151 00:08:50,920 --> 00:08:53,599 Speaker 1: those shrub sculptures from the Shining from you know, the 152 00:08:53,800 --> 00:08:56,840 Speaker 1: original novel. If you've read that, you know you you 153 00:08:56,840 --> 00:08:59,120 Speaker 1: you prune everything down, cut it away until it's the 154 00:08:59,120 --> 00:09:01,640 Speaker 1: the appropriate ape. Yeah. That's an interesting thing that the 155 00:09:01,640 --> 00:09:04,160 Speaker 1: speakers in this event talk about, is the idea of 156 00:09:04,200 --> 00:09:07,400 Speaker 1: pruning in childhood. How it starts off with way more 157 00:09:07,400 --> 00:09:10,679 Speaker 1: connections than it needs, and then through this process it 158 00:09:10,760 --> 00:09:13,200 Speaker 1: sort of pairs back the stuff that says, Okay, it 159 00:09:13,240 --> 00:09:14,920 Speaker 1: looks like I'm not going to need that in life. 160 00:09:14,920 --> 00:09:17,199 Speaker 1: We can just sever all those Yeah, I mean it 161 00:09:17,480 --> 00:09:20,560 Speaker 1: kind of matches up with the cliche of the child 162 00:09:20,640 --> 00:09:23,080 Speaker 1: who can grow up to be anything, right, which you know, 163 00:09:23,440 --> 00:09:26,560 Speaker 1: obviously any given child can't grow up to be absolutely anything. 164 00:09:26,720 --> 00:09:28,640 Speaker 1: But there is a there. There is a lot of 165 00:09:28,720 --> 00:09:32,400 Speaker 1: room for specialization and and and and diverse growth there. Yeah, 166 00:09:32,400 --> 00:09:35,880 Speaker 1: we have natural tendencies and natural potentials, and some of 167 00:09:35,920 --> 00:09:40,199 Speaker 1: that is genetic. But then also we were extremely adaptable 168 00:09:40,200 --> 00:09:42,920 Speaker 1: as children, right. But then of course in neural stability 169 00:09:42,960 --> 00:09:47,040 Speaker 1: has to kick in. That's important too, a necessary balance 170 00:09:47,080 --> 00:09:50,200 Speaker 1: in the human brain. Um, you're going to grow up 171 00:09:50,240 --> 00:09:53,320 Speaker 1: and become this thing we call an adult. But what 172 00:09:53,440 --> 00:09:56,320 Speaker 1: if I am Peter Pan and I don't want to 173 00:09:56,320 --> 00:09:58,760 Speaker 1: grow up and be an adult because growing up and 174 00:09:58,800 --> 00:10:02,280 Speaker 1: being an adult and having neuro stability limits my potential. 175 00:10:02,800 --> 00:10:05,200 Speaker 1: What if I decide I don't want to be somebody 176 00:10:05,240 --> 00:10:08,640 Speaker 1: who only speaks English. I want to be somebody who 177 00:10:08,880 --> 00:10:13,199 Speaker 1: speaks Chinese and speaks French and speaks the click languages. 178 00:10:13,320 --> 00:10:15,640 Speaker 1: And you know what if I want to speak all 179 00:10:15,679 --> 00:10:19,240 Speaker 1: those languages without an accent, Why can't I do that? Yeah? 180 00:10:19,320 --> 00:10:22,000 Speaker 1: I want to have infinite potential. Again, I want to 181 00:10:22,080 --> 00:10:23,640 Speaker 1: go back to I want to be able to grow 182 00:10:23,720 --> 00:10:26,200 Speaker 1: up to be anything. You know. I think we've all 183 00:10:26,200 --> 00:10:29,240 Speaker 1: had moments like that where we we we we we 184 00:10:29,280 --> 00:10:31,199 Speaker 1: look at where we are and we think, well, if 185 00:10:31,240 --> 00:10:33,320 Speaker 1: I could go back and open myself up to this 186 00:10:33,440 --> 00:10:35,840 Speaker 1: language or this ability or what have you, then I 187 00:10:35,840 --> 00:10:37,680 Speaker 1: would love to do that, you know, or just the 188 00:10:37,720 --> 00:10:40,520 Speaker 1: idea that nobody wants to. You don't want to feel stagnant. 189 00:10:40,520 --> 00:10:43,040 Speaker 1: You want to feel like you're continuing to grow and 190 00:10:43,200 --> 00:10:45,440 Speaker 1: uh and you know, keep up with the young ones. 191 00:10:46,280 --> 00:10:50,440 Speaker 1: And so scientists have continually looked to possible ways of 192 00:10:50,559 --> 00:10:56,839 Speaker 1: essentially rewidening the doorways of of neuroplasticity. That's one of 193 00:10:56,840 --> 00:10:58,920 Speaker 1: the metaphors it's often used, right, is that when you're 194 00:10:58,920 --> 00:11:01,640 Speaker 1: a child, the the door is open, the window is 195 00:11:01,679 --> 00:11:06,400 Speaker 1: open for you to grasp onto anything. But then depending 196 00:11:06,400 --> 00:11:08,120 Speaker 1: on who's throwing the metaphor around, you can say, well 197 00:11:08,120 --> 00:11:10,000 Speaker 1: it closes when you become an adult, but it doesn't 198 00:11:10,040 --> 00:11:14,319 Speaker 1: really close. It gets sort of like it gets almost closed, right, 199 00:11:14,360 --> 00:11:19,559 Speaker 1: it narrows. And so we've looked ways to to widen 200 00:11:19,640 --> 00:11:22,840 Speaker 1: it in adulthood. And and it goes beyond this mirror 201 00:11:23,000 --> 00:11:27,679 Speaker 1: um you know, intellectual vanity as well. Right, It's not 202 00:11:27,720 --> 00:11:30,199 Speaker 1: just Peter Pan saying, I want this, I want that. 203 00:11:30,240 --> 00:11:33,160 Speaker 1: There's also the idea of treating problems in the adult 204 00:11:33,200 --> 00:11:36,679 Speaker 1: brain by reintroducing plasticity, right, it would it would give 205 00:11:36,760 --> 00:11:42,040 Speaker 1: us a way to treat various neurodegenerative disorders, anxiety, depression, 206 00:11:42,360 --> 00:11:45,800 Speaker 1: even post traumatic stress disorder. Like anytime there's a there's 207 00:11:45,800 --> 00:11:48,439 Speaker 1: a potential for for growth and change, positive growth and 208 00:11:48,520 --> 00:11:51,280 Speaker 1: change in the brain to help with a given condition. 209 00:11:51,640 --> 00:11:54,959 Speaker 1: Neuroplasticity is often brought up as a as a potential cure, 210 00:11:55,240 --> 00:11:57,240 Speaker 1: but it's a challenge to do this sort of thing. 211 00:11:57,600 --> 00:12:01,760 Speaker 1: As a Columbia University developmental psychologist Dr Nim Totenham, who 212 00:12:01,760 --> 00:12:04,400 Speaker 1: were referenced already, as she stated in the in that 213 00:12:04,440 --> 00:12:08,320 Speaker 1: World Science festifal discussion, the brain actually extends expends a 214 00:12:08,360 --> 00:12:12,200 Speaker 1: lot of energy to keep critical periods from reopening. Yeah, 215 00:12:12,240 --> 00:12:15,760 Speaker 1: we there there seems to be some logic underlying this, 216 00:12:15,760 --> 00:12:18,680 Speaker 1: this move the evolution took right. It says, you know, 217 00:12:18,800 --> 00:12:21,360 Speaker 1: you don't stay a plastic child forever. At some point 218 00:12:21,400 --> 00:12:23,880 Speaker 1: the brain needs to figure out what to be and 219 00:12:23,960 --> 00:12:27,160 Speaker 1: be that right. And that's one of the reasons we're 220 00:12:27,320 --> 00:12:30,360 Speaker 1: calling this episode the Dark Side of Neural plasticity, not 221 00:12:30,440 --> 00:12:33,800 Speaker 1: that neuroplasticity. It necessarily has this deep, dark underbelly, but 222 00:12:34,040 --> 00:12:37,920 Speaker 1: the sort of public awareness tends to lean so heavily 223 00:12:38,000 --> 00:12:40,840 Speaker 1: towards neuroplastics is just an absolute good. I want as 224 00:12:40,920 --> 00:12:42,960 Speaker 1: much of it as I can get. We want to 225 00:12:43,000 --> 00:12:46,360 Speaker 1: counter the hype. Neuroplasticity is a good thing, but it's 226 00:12:46,400 --> 00:12:49,280 Speaker 1: also not an uh It's not a good thing in 227 00:12:49,440 --> 00:12:53,079 Speaker 1: every possible case, in every possible sense. Right, and towards 228 00:12:53,120 --> 00:12:56,320 Speaker 1: the end of the episode, Will will speculate a little 229 00:12:56,320 --> 00:12:59,079 Speaker 1: bit and look at some some speculation from experts about 230 00:12:59,120 --> 00:13:01,560 Speaker 1: what some of the possible pitfalls could be, What are 231 00:13:01,600 --> 00:13:03,760 Speaker 1: some and even what are some of the black mirror 232 00:13:03,960 --> 00:13:10,400 Speaker 1: esque possibilities in a world full of neuroplasticity inducing drugs. Yeah, now, 233 00:13:10,600 --> 00:13:14,000 Speaker 1: the question about these drugs, though, is still wide open. 234 00:13:14,080 --> 00:13:16,200 Speaker 1: I mean it's sort of h I hate to use 235 00:13:16,200 --> 00:13:18,559 Speaker 1: the metaphor the wild West. What's a better metaphor for 236 00:13:19,200 --> 00:13:21,960 Speaker 1: an arena in which there is still much much new 237 00:13:22,000 --> 00:13:26,120 Speaker 1: ground being forged? Welcome to the jungle, baby. How about 238 00:13:26,120 --> 00:13:30,080 Speaker 1: some spelunking. We're spelunking. Yeah, those are close confines, though, 239 00:13:30,080 --> 00:13:32,400 Speaker 1: I guess, Okay, I think I think wild West is 240 00:13:32,440 --> 00:13:36,040 Speaker 1: still pretty good. Well, whatever it is. I mean, we're 241 00:13:36,040 --> 00:13:39,160 Speaker 1: still trying to figure out what kinds of drugs might 242 00:13:39,200 --> 00:13:41,800 Speaker 1: do this, what side effects they might have, if they 243 00:13:41,840 --> 00:13:44,640 Speaker 1: are effective at doing it, And we'll talk more later 244 00:13:44,679 --> 00:13:46,960 Speaker 1: in the episode about what some of these specific drugs 245 00:13:47,040 --> 00:13:49,679 Speaker 1: might be. Yeah, because to master neuroplus this day, we're 246 00:13:49,679 --> 00:13:52,320 Speaker 1: going to have to establish the molecules that close the doors. 247 00:13:52,520 --> 00:13:55,240 Speaker 1: I mean, the thing is, it is possible to extend 248 00:13:55,280 --> 00:13:58,640 Speaker 1: critical periods and manipulate them, and experts do, in fact 249 00:13:58,679 --> 00:14:00,800 Speaker 1: think that will one day be able to do this 250 00:14:01,400 --> 00:14:03,760 Speaker 1: with a pill, with some sort of medication. So it's 251 00:14:03,760 --> 00:14:06,240 Speaker 1: not a question of if. It's a question of when 252 00:14:06,360 --> 00:14:09,760 Speaker 1: the groundwork is already being laid for this. Uh, it's 253 00:14:09,800 --> 00:14:11,360 Speaker 1: just how are we going to be ready for it 254 00:14:11,400 --> 00:14:13,400 Speaker 1: when it happens. Well, I think we should take a 255 00:14:13,440 --> 00:14:15,120 Speaker 1: quick break and then when we come back we will 256 00:14:15,240 --> 00:14:17,480 Speaker 1: discuss a few things about the history of the idea 257 00:14:17,520 --> 00:14:23,480 Speaker 1: of neuroplasticity. Than alright, we're back. So Charles Darwin actually 258 00:14:23,560 --> 00:14:27,280 Speaker 1: offered some thoughts about how the brain changes in response 259 00:14:27,320 --> 00:14:29,960 Speaker 1: to the environment in his book The Descent of Man, 260 00:14:30,040 --> 00:14:33,200 Speaker 1: which published in eighteen seventy four, and though We should 261 00:14:33,200 --> 00:14:36,200 Speaker 1: note that he did not use the term plasticity. He 262 00:14:36,280 --> 00:14:38,760 Speaker 1: did sort of write about the idea of of the 263 00:14:38,800 --> 00:14:42,120 Speaker 1: brain adapting. He wrote, quote, I have shown that the 264 00:14:42,160 --> 00:14:46,200 Speaker 1: brains of domestic rabbits are considerably reduced in bulk in 265 00:14:46,280 --> 00:14:49,720 Speaker 1: comparison with those of the wild rabbit or hair, and 266 00:14:49,760 --> 00:14:52,840 Speaker 1: this may be attributed to their having been closely confined 267 00:14:52,920 --> 00:14:58,360 Speaker 1: during many generations, so that they have exerted their intellect, instincts, senses, 268 00:14:58,400 --> 00:15:03,120 Speaker 1: and voluntary movements. But little uh, note that he's imagining 269 00:15:03,160 --> 00:15:06,960 Speaker 1: this adaptation of the brain taking place over multiple generations 270 00:15:07,000 --> 00:15:09,760 Speaker 1: through inheritance, which is very different from the kind of 271 00:15:09,760 --> 00:15:12,800 Speaker 1: plasticity that we're talking about, which takes place within a 272 00:15:12,840 --> 00:15:15,760 Speaker 1: single body within a single lifetime. But he is at 273 00:15:15,800 --> 00:15:18,520 Speaker 1: least offering an image. They're saying like, Okay, maybe the 274 00:15:18,560 --> 00:15:22,160 Speaker 1: brain can kind of be molded to what it best 275 00:15:22,320 --> 00:15:26,440 Speaker 1: does given its environmental circumstances. Right. If you, if you're 276 00:15:26,440 --> 00:15:28,480 Speaker 1: a wild hair and you need to be crafty and 277 00:15:28,560 --> 00:15:31,040 Speaker 1: wildly and use all your senses to survive out in 278 00:15:31,080 --> 00:15:34,640 Speaker 1: the brush, uh, you you will grow these bulky brains. 279 00:15:34,760 --> 00:15:36,920 Speaker 1: But if you're a domestic hair and all you do 280 00:15:37,000 --> 00:15:39,840 Speaker 1: is sit around and get fed, then you don't need 281 00:15:39,880 --> 00:15:42,560 Speaker 1: all that stuff and the brain will adapt. This touches 282 00:15:42,600 --> 00:15:44,360 Speaker 1: on a fact that we've discussed before, and that is 283 00:15:44,440 --> 00:15:47,040 Speaker 1: that that the that the brain like evolution, is a 284 00:15:47,040 --> 00:15:49,960 Speaker 1: miser and it's cheap. Yeah, it's it's cheap and once 285 00:15:50,040 --> 00:15:53,400 Speaker 1: the most economic model for functionality it is. It is 286 00:15:53,440 --> 00:15:56,760 Speaker 1: the Ebenezer Scrooge of the body. No, the whole body 287 00:15:56,840 --> 00:15:59,120 Speaker 1: is cheap. Actually, you know, it makes sense. You don't 288 00:15:59,120 --> 00:16:02,520 Speaker 1: want to be wasting energy in an environment where energy 289 00:16:02,600 --> 00:16:04,920 Speaker 1: is hard to come by, living in a world of 290 00:16:04,960 --> 00:16:08,320 Speaker 1: technology and abundance. Uh, you know, we should stop to 291 00:16:08,360 --> 00:16:10,800 Speaker 1: think how, you know, if if you have food to eat, 292 00:16:10,840 --> 00:16:12,840 Speaker 1: if you're not wondering where your next meal comes from, 293 00:16:12,880 --> 00:16:14,680 Speaker 1: you should think about how lucky you are. But you 294 00:16:14,680 --> 00:16:17,560 Speaker 1: should also think about how, in many ways your body 295 00:16:17,640 --> 00:16:19,960 Speaker 1: and the bodies of every other creature in the world, 296 00:16:20,240 --> 00:16:23,040 Speaker 1: we're sort of designed for scenarios where you would be 297 00:16:23,080 --> 00:16:26,000 Speaker 1: constantly living on the edge of starvation. But back to 298 00:16:26,120 --> 00:16:30,280 Speaker 1: neuro plasticity. So the term plasticity emerged from the work 299 00:16:30,360 --> 00:16:33,840 Speaker 1: of American psychologist William James who lived eighteen forty two 300 00:16:33,840 --> 00:16:37,640 Speaker 1: to nineteen ten, and James defined it the following way 301 00:16:37,680 --> 00:16:41,080 Speaker 1: he said, it's quote the possession of a structure weak 302 00:16:41,240 --> 00:16:44,920 Speaker 1: enough to yield an influence, but strong enough not to 303 00:16:45,000 --> 00:16:47,640 Speaker 1: yield all at once. Yeah, I mean that makes sense. 304 00:16:48,560 --> 00:16:51,600 Speaker 1: It's ideal for a young child to be open to 305 00:16:51,640 --> 00:16:55,480 Speaker 1: their environment and not so open that they're just completely overwhelmed. Right. 306 00:16:55,520 --> 00:16:58,360 Speaker 1: So I want to read a quote from William James 307 00:16:58,440 --> 00:17:01,800 Speaker 1: from his from his seminar work on psychology, where he 308 00:17:01,960 --> 00:17:04,879 Speaker 1: started deposit that the brain might have some kind of 309 00:17:05,600 --> 00:17:09,719 Speaker 1: might have some kind of like changeable structure. So he says, quote, 310 00:17:10,359 --> 00:17:13,520 Speaker 1: if habits are due to the plasticity of materials to 311 00:17:13,640 --> 00:17:17,879 Speaker 1: outward agents, we can immediately see to what outward influences, 312 00:17:17,920 --> 00:17:21,800 Speaker 1: if to any the brain matter is plastic, not too 313 00:17:21,880 --> 00:17:26,359 Speaker 1: mechanical pressures, not to thermal changes, not to any of 314 00:17:26,400 --> 00:17:28,719 Speaker 1: the forces to which all the other organs of our 315 00:17:28,760 --> 00:17:32,840 Speaker 1: body are exposed. For nature has so blanketed and wrapped 316 00:17:32,880 --> 00:17:35,719 Speaker 1: the brain about that the only impressions that can be 317 00:17:35,800 --> 00:17:39,160 Speaker 1: made upon it are through the blood on the one hand, 318 00:17:39,480 --> 00:17:42,879 Speaker 1: and the sensory nerve roots on the other. And it 319 00:17:43,000 --> 00:17:46,400 Speaker 1: is to the infinitely attenuated currents that pour in through 320 00:17:46,440 --> 00:17:50,800 Speaker 1: these latter channels that the hemispherical cortex shows itself to 321 00:17:50,840 --> 00:17:55,639 Speaker 1: be so peculiarly susceptible. The currents, once in, must find 322 00:17:55,640 --> 00:17:59,000 Speaker 1: a way out. In getting out, they leave their traces 323 00:17:59,040 --> 00:18:02,320 Speaker 1: in the paths which they take. The only thing they 324 00:18:02,440 --> 00:18:06,119 Speaker 1: can do, in short, is to deepen old paths or 325 00:18:06,160 --> 00:18:09,040 Speaker 1: to make new ones. And the whole plasticity of the 326 00:18:09,080 --> 00:18:12,360 Speaker 1: brain sums itself up in two words when we call 327 00:18:12,440 --> 00:18:15,159 Speaker 1: it an organ in which currents pouring in from the 328 00:18:15,200 --> 00:18:19,399 Speaker 1: sense organs make with extreme facility paths which do not 329 00:18:19,560 --> 00:18:24,040 Speaker 1: easily disappear. For, of course, a simple habit, like every 330 00:18:24,080 --> 00:18:27,879 Speaker 1: other nervous event, the habit of snuffling, for example, or 331 00:18:27,920 --> 00:18:31,680 Speaker 1: putting one's hands into one's pockets or biting one's nails, 332 00:18:32,240 --> 00:18:37,160 Speaker 1: is mechanically nothing but a reflex discharge, and its anatomical 333 00:18:37,240 --> 00:18:41,119 Speaker 1: substratum must be a path in the system. The most 334 00:18:41,280 --> 00:18:44,520 Speaker 1: complex habits, as we shall presently see more fully, are, 335 00:18:44,640 --> 00:18:48,280 Speaker 1: from the same point of view, nothing but concatenated discharges 336 00:18:48,320 --> 00:18:51,159 Speaker 1: of the nerve centers, due to the presence there of 337 00:18:51,359 --> 00:18:56,160 Speaker 1: systems of reflex paths so organized as to wake each 338 00:18:56,160 --> 00:19:00,359 Speaker 1: other up successively. The impression produced by one skill or 339 00:19:00,440 --> 00:19:03,960 Speaker 1: contractions serving as a stimulus to provoke the next until 340 00:19:04,000 --> 00:19:08,320 Speaker 1: a final impression inhibits the process and closes the chain. 341 00:19:09,119 --> 00:19:12,400 Speaker 1: So that was very forward thinking on William James's part. 342 00:19:13,400 --> 00:19:17,440 Speaker 1: He's so, he's got a very rudimentary nineteenth century understanding 343 00:19:17,480 --> 00:19:20,040 Speaker 1: of brain function here, but it does get some some 344 00:19:20,160 --> 00:19:24,400 Speaker 1: interesting basic insights right. One of them is that habits 345 00:19:24,480 --> 00:19:26,680 Speaker 1: or tendencies of the brain consist of a kind of 346 00:19:26,720 --> 00:19:32,200 Speaker 1: reinforcing of pathways of activities. Another is that complex brain 347 00:19:32,240 --> 00:19:35,480 Speaker 1: functions are built out of many less complex brain functions 348 00:19:35,480 --> 00:19:39,000 Speaker 1: happening together in sequence. Another is that the potential and 349 00:19:39,080 --> 00:19:43,240 Speaker 1: predispositions of an individual brain like your brain, can be 350 00:19:43,520 --> 00:19:47,679 Speaker 1: changed based on repeated interaction with chemicals in the blood 351 00:19:48,040 --> 00:19:50,680 Speaker 1: or with the data of the senses. And that last 352 00:19:50,720 --> 00:19:53,560 Speaker 1: part is just as a tangent, one of those utterly 353 00:19:53,680 --> 00:19:56,399 Speaker 1: mundane facts that I often have to stop and force 354 00:19:56,480 --> 00:19:59,359 Speaker 1: myself to be amazed by over and over again, Like 355 00:19:59,440 --> 00:20:03,160 Speaker 1: think about this. It sounds kind of stupid to say, 356 00:20:03,200 --> 00:20:06,959 Speaker 1: but by making acoustic vibrations in the air with my 357 00:20:07,080 --> 00:20:10,320 Speaker 1: mouth that you can hear, or by like drawing a 358 00:20:10,320 --> 00:20:12,879 Speaker 1: picture on a chalkboard and putting it in front of 359 00:20:12,880 --> 00:20:17,280 Speaker 1: your eyes, I can literally change the physical configuration of 360 00:20:17,320 --> 00:20:21,720 Speaker 1: your brain. I make changes inside your skull by doing 361 00:20:21,760 --> 00:20:24,760 Speaker 1: things you can see in here. Isn't that bizarre? Yeah? 362 00:20:24,800 --> 00:20:26,320 Speaker 1: I mean if you and if you extend it to 363 00:20:26,520 --> 00:20:30,640 Speaker 1: written language, you can think, oh, well, somebody who wrote something, uh, 364 00:20:30,760 --> 00:20:35,160 Speaker 1: inscribed something down a thousand, two thousand, three thousand years ago. 365 00:20:35,920 --> 00:20:40,200 Speaker 1: They can speak across all those uh, those dead millennia, 366 00:20:40,480 --> 00:20:42,400 Speaker 1: and they can speak right to our brain and make 367 00:20:42,520 --> 00:20:45,679 Speaker 1: changes in it. It's unbelievable. Now. I mentioned earlier that 368 00:20:45,760 --> 00:20:48,840 Speaker 1: the term plasticity in the context of neuroscience had been 369 00:20:48,920 --> 00:20:50,879 Speaker 1: used to mean a lot of different things. There was 370 00:20:50,920 --> 00:20:54,320 Speaker 1: one particular paper I looked at about this by Giovanni 371 00:20:54,359 --> 00:20:57,679 Speaker 1: Berluki and Henry book Tool from two thousand nine and 372 00:20:57,760 --> 00:21:00,640 Speaker 1: Experimental Brain Research, and they talk about how the term 373 00:21:00,680 --> 00:21:03,800 Speaker 1: plasticity has been used over the past century to refer 374 00:21:03,840 --> 00:21:07,159 Speaker 1: to quote changes in neural organization, which may account for 375 00:21:07,320 --> 00:21:11,560 Speaker 1: various forms of behavioral modifiability, either short lasting or enduring, 376 00:21:11,680 --> 00:21:17,320 Speaker 1: including maturation, adaptation to a mutable environment, specific and unspecific 377 00:21:17,400 --> 00:21:21,800 Speaker 1: kinds of learning, and compensatory adjustments in response to functional 378 00:21:21,840 --> 00:21:25,320 Speaker 1: losses from aging or brain damage. So that that's a 379 00:21:25,359 --> 00:21:29,000 Speaker 1: lot of different meanings encompassed in the idea of plasticity, 380 00:21:29,040 --> 00:21:31,479 Speaker 1: but it does sort of apply to all of those, 381 00:21:31,800 --> 00:21:34,800 Speaker 1: so it's subject to generalization. But then also is sort 382 00:21:34,840 --> 00:21:37,080 Speaker 1: of uh is a turn It sort of refers to 383 00:21:37,200 --> 00:21:40,119 Speaker 1: general change in the brain. Yeah, a kind of adaptation 384 00:21:40,160 --> 00:21:42,800 Speaker 1: that has come to be associated with pressures put on 385 00:21:42,840 --> 00:21:46,280 Speaker 1: the brain from the environment. Right. So, with modern techniques, 386 00:21:46,280 --> 00:21:48,960 Speaker 1: we've discovered that the way these pathways are forged and 387 00:21:49,000 --> 00:21:53,400 Speaker 1: reinforced in the brain depends largely on the crucial element 388 00:21:53,520 --> 00:21:56,159 Speaker 1: of the synapps or you know, the bridge of space 389 00:21:56,200 --> 00:21:59,600 Speaker 1: that connects to nerve cells and allows impulses to pass 390 00:21:59,640 --> 00:22:04,359 Speaker 1: between the cells. And in eight three, the Italian neuropsychiatrist 391 00:22:04,440 --> 00:22:09,359 Speaker 1: Eugenio Tanzi first proposed that the basis of practice based 392 00:22:09,440 --> 00:22:14,480 Speaker 1: learning and associative memory was these connections between nerve cells 393 00:22:14,480 --> 00:22:17,520 Speaker 1: in the brain. Because Tanzi knew that there are other 394 00:22:17,560 --> 00:22:21,000 Speaker 1: scientists who had observed the slowing of the passage of 395 00:22:21,080 --> 00:22:24,239 Speaker 1: nerve impulses through the gray matter in the brain, and 396 00:22:24,240 --> 00:22:26,919 Speaker 1: so he hypothesized that maybe what's going on in that 397 00:22:27,080 --> 00:22:31,600 Speaker 1: slow down is that there's difficulty for the impulses to 398 00:22:31,720 --> 00:22:35,120 Speaker 1: cross the gaps between neurons, These gaps that we now 399 00:22:35,160 --> 00:22:39,080 Speaker 1: call synapses or synaptic fissures, and based on that assumption, 400 00:22:39,440 --> 00:22:42,440 Speaker 1: Tansi argued that the way the brain adapts, the way 401 00:22:42,480 --> 00:22:46,879 Speaker 1: it learns through practice and creates associations between things, the 402 00:22:46,920 --> 00:22:50,359 Speaker 1: way it sort of enacts its plastic potential is by 403 00:22:50,400 --> 00:22:54,480 Speaker 1: a kind of exercise. When you perform a repetitious activity 404 00:22:54,520 --> 00:22:58,760 Speaker 1: in the brain, the same pathways of neurons repeatedly communicate 405 00:22:58,800 --> 00:23:01,200 Speaker 1: with each other, and by doing this you cause a 406 00:23:01,320 --> 00:23:04,720 Speaker 1: kind of hypertrophy or strengthening of the connections between those 407 00:23:04,760 --> 00:23:07,560 Speaker 1: specific neurons. The more you do a certain thing in 408 00:23:07,560 --> 00:23:10,639 Speaker 1: the brain, the easier that that thing becomes to do 409 00:23:10,800 --> 00:23:14,840 Speaker 1: in the brain. And then the next year. In the 410 00:23:14,840 --> 00:23:19,560 Speaker 1: Spanish neuroscientists Santiago Ramoni Kahal, who I've thought before we 411 00:23:19,600 --> 00:23:22,040 Speaker 1: should do a whole episode on this guy. Perhaps he 412 00:23:22,119 --> 00:23:25,359 Speaker 1: also speculated that learning was based on the creation and 413 00:23:25,400 --> 00:23:29,240 Speaker 1: strengthening of connections between neurons. I feel like this is 414 00:23:29,280 --> 00:23:32,040 Speaker 1: something that has been I think over the years, it's 415 00:23:32,080 --> 00:23:35,639 Speaker 1: just been so well demonstrated, or not really demonstrated, but 416 00:23:35,680 --> 00:23:40,200 Speaker 1: illustrated with animations and and uh and and art that 417 00:23:40,520 --> 00:23:42,679 Speaker 1: I have it like well ingrained in my head, Like 418 00:23:42,680 --> 00:23:47,560 Speaker 1: when people talk start talking about synopsis firing. I picture it, 419 00:23:47,880 --> 00:23:49,800 Speaker 1: and maybe I also kind of think of it in 420 00:23:49,920 --> 00:23:52,880 Speaker 1: terms of of playing an instrument, like the physical act 421 00:23:52,920 --> 00:23:56,600 Speaker 1: of playing an instrument of linking, um, you know, of 422 00:23:56,880 --> 00:23:59,840 Speaker 1: finger movements on say a trumpet or French worn to 423 00:24:00,119 --> 00:24:02,280 Speaker 1: the note that you're playing, and then linking those in 424 00:24:02,400 --> 00:24:05,600 Speaker 1: order to create, uh, the notes in a particular tune, 425 00:24:06,040 --> 00:24:10,520 Speaker 1: which of course is both literally a synaptic learning exercise, 426 00:24:10,560 --> 00:24:13,680 Speaker 1: but also kind of an illustration of what's going on, 427 00:24:13,880 --> 00:24:16,920 Speaker 1: like making this, connecting it to that, and then leading 428 00:24:16,960 --> 00:24:19,480 Speaker 1: onto the next note. Yeah, we we've learned this in 429 00:24:19,520 --> 00:24:21,800 Speaker 1: the modern age, and so it's easy for us to picture, 430 00:24:21,840 --> 00:24:25,480 Speaker 1: but we should appreciate how how interesting of an insight 431 00:24:25,600 --> 00:24:27,760 Speaker 1: this was for for the people at the time, because 432 00:24:27,760 --> 00:24:31,520 Speaker 1: there were also competing hypotheses in the late nineteenth and 433 00:24:31,520 --> 00:24:35,119 Speaker 1: early twentieth century, like Berlukian book Toll show that in 434 00:24:35,160 --> 00:24:37,800 Speaker 1: the first couple of decades of the twentieth century that 435 00:24:38,000 --> 00:24:41,000 Speaker 1: this idea of the sort of learning through quote reduced 436 00:24:41,040 --> 00:24:46,359 Speaker 1: resistance that exercise synapses, uh, that that idea was pretty 437 00:24:46,359 --> 00:24:48,479 Speaker 1: widely accepted in that first couple of decades, and then 438 00:24:48,520 --> 00:24:51,760 Speaker 1: for a while it really went into decline. This the 439 00:24:51,760 --> 00:24:55,480 Speaker 1: synaptic model of plasticity due to arise in the popularity 440 00:24:55,480 --> 00:24:58,439 Speaker 1: of competing ideas about all this weird stuff about the 441 00:24:58,440 --> 00:25:01,720 Speaker 1: equipotential version end of the brain. But anyway, in the 442 00:25:01,800 --> 00:25:04,480 Speaker 1: late nineteen forties it came back. It was sort of 443 00:25:04,520 --> 00:25:08,720 Speaker 1: rehabilitated by scientists like the Polish neuroscientists Jersey Konorski and 444 00:25:08,760 --> 00:25:12,800 Speaker 1: the Canadian psychologist Donald Hebb, and Hebb was particularly influential, 445 00:25:13,560 --> 00:25:17,679 Speaker 1: and then experimental evidence accumulated during the twentieth century, especially 446 00:25:17,760 --> 00:25:20,280 Speaker 1: during the mid and later twentieth century, from the likes 447 00:25:20,320 --> 00:25:26,160 Speaker 1: of David Hubel and Torsten VISal, Michael Merzenek, and Eleanor McGuire. Now, 448 00:25:26,200 --> 00:25:29,240 Speaker 1: the work of each of those individuals is is fascinating, 449 00:25:29,320 --> 00:25:31,040 Speaker 1: and I would love to come back and look at 450 00:25:31,080 --> 00:25:34,440 Speaker 1: them in greater detail. There's some wonderful work they're regarding, uh, 451 00:25:34,480 --> 00:25:36,680 Speaker 1: you know, how how we see the world. I mean, 452 00:25:36,680 --> 00:25:39,920 Speaker 1: some of the very basic questions about the human experience, 453 00:25:40,720 --> 00:25:42,720 Speaker 1: how how do we perceive the world and how is 454 00:25:42,760 --> 00:25:45,800 Speaker 1: it processed in the brain are explored by by by 455 00:25:45,840 --> 00:25:50,040 Speaker 1: their work. But the interesting thing is there's still something 456 00:25:50,080 --> 00:25:53,840 Speaker 1: of a controversy about exactly how plastic the adult human 457 00:25:53,880 --> 00:25:57,199 Speaker 1: brain is, if much at all like For most of 458 00:25:57,200 --> 00:26:00,239 Speaker 1: the history of neuroscience. Up until very recently, a lot 459 00:26:00,280 --> 00:26:03,960 Speaker 1: of experts believed that the human adult brain had almost 460 00:26:04,000 --> 00:26:07,080 Speaker 1: no plasticity, you know, that it was fixed and stable. 461 00:26:07,840 --> 00:26:10,160 Speaker 1: But at the same time, it's obvious that adults can 462 00:26:10,240 --> 00:26:13,159 Speaker 1: learn new things and adapt. Yeah, we can change, and 463 00:26:13,160 --> 00:26:15,800 Speaker 1: then we don't have to undergo, you know, catastrophic brain 464 00:26:15,840 --> 00:26:18,440 Speaker 1: injury for it to happen, right, So exactly how much 465 00:26:18,520 --> 00:26:21,760 Speaker 1: potential for change in plasticity is there in the adult 466 00:26:21,800 --> 00:26:25,280 Speaker 1: brain and in what areas like? It appears much easier 467 00:26:25,280 --> 00:26:28,000 Speaker 1: for adults to learn and adapt in some ways than 468 00:26:28,040 --> 00:26:31,359 Speaker 1: it does in others. Language acquisition, as we've talked about 469 00:26:31,359 --> 00:26:34,359 Speaker 1: as a classic example, Um, you know, children are just 470 00:26:34,520 --> 00:26:38,120 Speaker 1: so so much better at learning a language than adults are. 471 00:26:38,600 --> 00:26:42,199 Speaker 1: Another one is certain aspects of music learning. Have you 472 00:26:42,240 --> 00:26:44,720 Speaker 1: read about perfect pitch? Probably, yes, Yeah, you have to 473 00:26:44,760 --> 00:26:46,880 Speaker 1: get it early or you're not gonna you're not gonna 474 00:26:46,880 --> 00:26:49,400 Speaker 1: get it later on. Yeah. This is a commonly cited example. 475 00:26:50,000 --> 00:26:52,800 Speaker 1: Robert sing a middle c oh, I I don't. I 476 00:26:52,800 --> 00:26:56,280 Speaker 1: don't do music like that, Joe, Almost no adults do 477 00:26:56,720 --> 00:27:00,440 Speaker 1: unless you've you've trained on it before you were roughly 478 00:27:00,480 --> 00:27:03,639 Speaker 1: six years old. Right, So if you have this skill 479 00:27:03,720 --> 00:27:06,360 Speaker 1: known as perfect pitch, you should be able to recognize 480 00:27:06,480 --> 00:27:10,040 Speaker 1: or produce not just tones relative to other tones, but 481 00:27:10,160 --> 00:27:12,119 Speaker 1: like you could call out a note and the person 482 00:27:12,160 --> 00:27:15,040 Speaker 1: would know what that pitch actually was. They could sing it, 483 00:27:15,480 --> 00:27:18,320 Speaker 1: or they could recognize it in hearing it. Yeah. I 484 00:27:18,560 --> 00:27:20,960 Speaker 1: My my reaction to that question is the same as 485 00:27:20,960 --> 00:27:23,200 Speaker 1: the other day when my son asked me what Thursday 486 00:27:23,200 --> 00:27:26,480 Speaker 1: plus Thursday equals, and it's just like, I can't. That 487 00:27:26,560 --> 00:27:28,360 Speaker 1: just broke my brain a little bit to even try 488 00:27:28,400 --> 00:27:31,280 Speaker 1: and answer that question. It sounds like a three key 489 00:27:31,280 --> 00:27:35,560 Speaker 1: Thursday probably, But yeah, So Supposedly the idea is if 490 00:27:35,560 --> 00:27:38,880 Speaker 1: you teach children to recognize pitches in an absolute sense 491 00:27:38,920 --> 00:27:42,880 Speaker 1: before they're roughly six years older, so they can potentially 492 00:27:42,920 --> 00:27:45,320 Speaker 1: acquire this skill. It's just like you've got to You've 493 00:27:45,320 --> 00:27:48,080 Speaker 1: got to get going within that window. Yeah, I feel 494 00:27:48,119 --> 00:27:50,840 Speaker 1: like I'm I'm wasting my time reading the hobbit to 495 00:27:50,880 --> 00:27:52,840 Speaker 1: my son. We should be we should be working on 496 00:27:52,880 --> 00:27:54,720 Speaker 1: this pitch thing. Well, there are all kinds of things 497 00:27:54,720 --> 00:27:56,800 Speaker 1: potentially like this that you don't even know about that 498 00:27:56,960 --> 00:27:59,520 Speaker 1: maybe you should be teaching your son at this critical 499 00:27:59,560 --> 00:28:03,879 Speaker 1: age before the window doesn't close but gets very narrow. Yeah. Well, 500 00:28:03,920 --> 00:28:05,800 Speaker 1: I mean there is a lot of a lot of 501 00:28:05,800 --> 00:28:08,639 Speaker 1: discussion of this out there in parenting forums and actual 502 00:28:09,400 --> 00:28:14,240 Speaker 1: you know, pure viewed child rearing material just about Yeah, 503 00:28:14,280 --> 00:28:16,239 Speaker 1: these are the ages of childhood when you want to 504 00:28:16,320 --> 00:28:18,800 Speaker 1: throw a bunch of different activities at them. You want 505 00:28:18,840 --> 00:28:21,120 Speaker 1: them to have some sort of musical training, some sort 506 00:28:21,160 --> 00:28:25,840 Speaker 1: of uh training in another language, etcetera like this, This 507 00:28:25,920 --> 00:28:28,760 Speaker 1: is when the this is when the windows are open, 508 00:28:28,880 --> 00:28:31,040 Speaker 1: so you want to just throw as much stuff there 509 00:28:31,040 --> 00:28:33,680 Speaker 1: there as possible. But I mean, wouldn't it be great 510 00:28:33,720 --> 00:28:35,800 Speaker 1: if you could be like that again as an adult? 511 00:28:35,840 --> 00:28:37,919 Speaker 1: As we were talking about earlier, the desire to be 512 00:28:37,960 --> 00:28:40,800 Speaker 1: Peter Pan, are are there things that we could do 513 00:28:41,120 --> 00:28:44,640 Speaker 1: to make the adult brain a learning and adaptation machine 514 00:28:44,960 --> 00:28:47,400 Speaker 1: like the young child's brain. A lot of people have 515 00:28:47,440 --> 00:28:49,760 Speaker 1: been asking that question, and so I guess that's what 516 00:28:49,800 --> 00:28:53,800 Speaker 1: we should explore now, the idea of induced to neuroplasticity 517 00:28:53,800 --> 00:28:57,000 Speaker 1: and adults. That's right. And as as we said earlier, 518 00:28:57,600 --> 00:29:01,240 Speaker 1: it's it's generally accepted that we and do this. It's 519 00:29:01,360 --> 00:29:03,920 Speaker 1: it's what we have to do is figure out exactly 520 00:29:03,960 --> 00:29:06,920 Speaker 1: how to do it. It's it's basically we want to 521 00:29:06,960 --> 00:29:11,520 Speaker 1: be neural puppet masters, but we are only just beginning 522 00:29:11,600 --> 00:29:14,640 Speaker 1: to really understand where all the strings are and then 523 00:29:15,280 --> 00:29:18,160 Speaker 1: what happens when you pull those strings? And then how 524 00:29:18,200 --> 00:29:20,160 Speaker 1: do you pull those strings? Do you just yank on them? 525 00:29:20,200 --> 00:29:22,040 Speaker 1: Or is it more of a delicate thing. We were 526 00:29:22,360 --> 00:29:25,840 Speaker 1: trying to to to master an art form of puppetry 527 00:29:25,880 --> 00:29:29,040 Speaker 1: that is currently beyond us. Right. It's not can we 528 00:29:29,080 --> 00:29:30,920 Speaker 1: do this at all? We're pretty sure we will be 529 00:29:30,960 --> 00:29:33,800 Speaker 1: able to do this to some extent. It's how well 530 00:29:33,920 --> 00:29:36,040 Speaker 1: can you do it? How well can you target it 531 00:29:36,080 --> 00:29:38,000 Speaker 1: for the kinds of things you want to do with it, 532 00:29:38,200 --> 00:29:41,560 Speaker 1: how well can you avoid negative side effects coming with it? 533 00:29:41,640 --> 00:29:43,680 Speaker 1: All that kind of stuff, and what are the best 534 00:29:43,760 --> 00:29:46,600 Speaker 1: drugs to do it with? Right? And there there have 535 00:29:46,640 --> 00:29:50,720 Speaker 1: been some experiments involving induced neuro plasticity and mice, a 536 00:29:50,760 --> 00:29:53,480 Speaker 1: lot of those, Yeah, and uh, you know, those show 537 00:29:53,800 --> 00:29:57,680 Speaker 1: a lot of promise in my understanding, But then anytime 538 00:29:57,720 --> 00:30:00,960 Speaker 1: we're looking at experiments with with mice, yes, mice are 539 00:30:00,960 --> 00:30:04,800 Speaker 1: are our great stand ins for human physiology, but there, 540 00:30:04,800 --> 00:30:08,360 Speaker 1: of course are not humans. So and there are a 541 00:30:08,360 --> 00:30:13,280 Speaker 1: lot of differences between rodents and humans, especially in the brain. Right. Yes, 542 00:30:13,800 --> 00:30:15,360 Speaker 1: so there are a lot of questions that are that 543 00:30:15,440 --> 00:30:17,680 Speaker 1: are not really going to be answered until we we 544 00:30:17,680 --> 00:30:19,800 Speaker 1: we better understand what we're doing with the mice and 545 00:30:19,880 --> 00:30:22,760 Speaker 1: also get more and more into actually testing some of 546 00:30:22,760 --> 00:30:25,840 Speaker 1: these treatments on humans. Well, let's look at a couple 547 00:30:25,880 --> 00:30:30,920 Speaker 1: of examples of research on drug induced neuroplasticity. Yeah, and uh, 548 00:30:31,000 --> 00:30:32,680 Speaker 1: you know, we're certainly not gonna be able to cover 549 00:30:32,720 --> 00:30:34,320 Speaker 1: all of it. As you mentioned earlier, a lot of 550 00:30:34,360 --> 00:30:38,760 Speaker 1: the research out there is either is either the deep 551 00:30:38,880 --> 00:30:42,120 Speaker 1: end of the pool or the obscenely shallow end of 552 00:30:41,960 --> 00:30:45,520 Speaker 1: the pool. And uh, and it's sometimes difficult to make 553 00:30:45,560 --> 00:30:48,680 Speaker 1: sense even for us, of the deeper end of the 554 00:30:48,680 --> 00:30:51,320 Speaker 1: neuroscientific pool. Well, we'll try to walk you up just 555 00:30:51,360 --> 00:30:55,080 Speaker 1: to your armpits or so. Yeah, this first study actually 556 00:30:55,200 --> 00:30:59,320 Speaker 1: emerged this year. So psychedelic drugs have long been associated 557 00:30:59,360 --> 00:31:02,280 Speaker 1: with an opening of the mind, right, and a June two, 558 00:31:02,520 --> 00:31:05,600 Speaker 1: eighteen study published in Cell Press points to evidence of 559 00:31:05,640 --> 00:31:10,880 Speaker 1: psychedelic induced neuroplasticity in rats and flies. And um, I 560 00:31:10,920 --> 00:31:13,320 Speaker 1: have to say I found this very interesting too, because 561 00:31:13,360 --> 00:31:16,320 Speaker 1: there's actually a part in alan Moore's v for Vendetta, 562 00:31:16,640 --> 00:31:19,720 Speaker 1: the original graphic novel. I don't think this is represented 563 00:31:19,760 --> 00:31:22,040 Speaker 1: in the film version, but you see one of the 564 00:31:22,040 --> 00:31:25,120 Speaker 1: main characters take l s D at the side of 565 00:31:25,120 --> 00:31:29,080 Speaker 1: a government resettlement camp. Uh, kind of opening himself up 566 00:31:29,120 --> 00:31:31,640 Speaker 1: to the full horror of the place and his connection 567 00:31:31,720 --> 00:31:35,360 Speaker 1: to it. It's a it's a very powerful scene. But 568 00:31:35,360 --> 00:31:39,480 Speaker 1: that doesn't directly relate to this study. So this University 569 00:31:39,480 --> 00:31:43,080 Speaker 1: of California Davis study examine the effects of several drugs 570 00:31:43,400 --> 00:31:46,960 Speaker 1: in test tube and animal experience experiments, including M d 571 00:31:47,080 --> 00:31:49,480 Speaker 1: m A, d m T, l s D, and the 572 00:31:49,520 --> 00:31:52,320 Speaker 1: ephetamine d O I, and they found that d o I, 573 00:31:52,560 --> 00:31:55,160 Speaker 1: d m T, and l s D in particular made 574 00:31:55,240 --> 00:31:58,320 Speaker 1: neurons more likely to branch out and develop. Based on 575 00:31:58,360 --> 00:32:01,560 Speaker 1: their findings, the u C. Davis team thinks that psychedelic 576 00:32:01,600 --> 00:32:04,160 Speaker 1: compounds such as DO d O I, d m T 577 00:32:04,240 --> 00:32:09,440 Speaker 1: analyst may eventually pave the way for prescription neuroplasticity drugs. 578 00:32:09,840 --> 00:32:12,560 Speaker 1: It's just all a matter of capitalizing on their ability 579 00:32:12,600 --> 00:32:18,320 Speaker 1: to expand the very neural circuits observed to atrophy during depression, anxiety, 580 00:32:18,360 --> 00:32:22,520 Speaker 1: and PTSD, so they observe functional and structural changes in 581 00:32:23,080 --> 00:32:27,200 Speaker 1: cortical neurons for both vertebrates and invertebrates exposed to psychedelic 582 00:32:27,240 --> 00:32:31,440 Speaker 1: compounds and isolated activity to the to the protein called 583 00:32:31,560 --> 00:32:36,160 Speaker 1: brain derived neurotrophic factor or b d n F, and 584 00:32:36,200 --> 00:32:39,240 Speaker 1: when b d n F was blocked, the psychedelics lost 585 00:32:39,240 --> 00:32:42,000 Speaker 1: their ability to promote neural growth. And the case proved 586 00:32:42,000 --> 00:32:45,200 Speaker 1: to be the same with the m tour signaling pathway, 587 00:32:45,400 --> 00:32:48,920 Speaker 1: which plays a role in creating proteins for new sign 588 00:32:49,000 --> 00:32:51,520 Speaker 1: apps formation. If you think of the brain as a 589 00:32:51,560 --> 00:32:54,680 Speaker 1: complex map, then this research places two key markers on 590 00:32:54,840 --> 00:32:58,960 Speaker 1: what could one day prove the pathway to induce neuro plasticity. 591 00:32:59,080 --> 00:33:01,160 Speaker 1: Though judging from what I've read that it seems like 592 00:33:01,240 --> 00:33:03,360 Speaker 1: there could be a lot of pathway. Yeah, oh yes. 593 00:33:03,440 --> 00:33:06,280 Speaker 1: And senior author and U. C. Davis Assistant chemistry Professor 594 00:33:06,360 --> 00:33:08,720 Speaker 1: David E. Olsen on this these stresses that there's there's 595 00:33:08,720 --> 00:33:11,240 Speaker 1: still a lot to learn here and that his team's 596 00:33:11,280 --> 00:33:14,520 Speaker 1: experiments didn't entail human trials, of course, but but it 597 00:33:14,600 --> 00:33:18,120 Speaker 1: is enough to suggest that the mind expanding aspects of 598 00:33:18,160 --> 00:33:22,000 Speaker 1: psychedelics as we understand them may one day adis and 599 00:33:22,120 --> 00:33:25,120 Speaker 1: creating new treatments. So I want to underline that the 600 00:33:25,320 --> 00:33:27,960 Speaker 1: researchers here are not saying go and take a bunch 601 00:33:27,960 --> 00:33:31,000 Speaker 1: of LSD and then try and learn Mandarin or develop 602 00:33:31,080 --> 00:33:35,239 Speaker 1: perfect pitch. They're saying that there are potentially things in 603 00:33:35,320 --> 00:33:39,640 Speaker 1: these substances that we could utilize to create far better, 604 00:33:39,800 --> 00:33:43,400 Speaker 1: far more targeted substances in the future. Now, though there 605 00:33:43,440 --> 00:33:47,640 Speaker 1: are some results indicating the possibility of induced neuroplasticity and 606 00:33:47,680 --> 00:33:51,600 Speaker 1: adults and adult humans, these are preliminary, intentative. As we 607 00:33:51,920 --> 00:33:53,840 Speaker 1: want to keep stressing this is one of those areas 608 00:33:53,840 --> 00:33:56,880 Speaker 1: where I would really expect to continue to see a 609 00:33:56,920 --> 00:34:00,400 Speaker 1: lot of controversy about the validity of results over the 610 00:34:00,440 --> 00:34:03,840 Speaker 1: next decade or the next couple of decades or so. UM. 611 00:34:04,120 --> 00:34:07,800 Speaker 1: I think it's it's important to stress amidst all of 612 00:34:07,840 --> 00:34:11,800 Speaker 1: the hype and the advertising and all that about neuroplasticity, 613 00:34:11,880 --> 00:34:14,520 Speaker 1: become a master of your brain, that that we're not 614 00:34:14,640 --> 00:34:18,279 Speaker 1: there yet. This stuff is not ready for prime time. Right. 615 00:34:18,640 --> 00:34:22,000 Speaker 1: I can't remember who made this comparison, but I believe 616 00:34:22,040 --> 00:34:24,600 Speaker 1: it was pointed out that when when we tinker with 617 00:34:24,719 --> 00:34:26,440 Speaker 1: the with the way our brain and even the way 618 00:34:26,440 --> 00:34:31,319 Speaker 1: our bodies work, especially with with various pharmaceuticals, it's kind 619 00:34:31,360 --> 00:34:33,319 Speaker 1: of like trying to change the oil in a car 620 00:34:33,480 --> 00:34:35,719 Speaker 1: by just dumping the motor oil direct, like opening the 621 00:34:35,719 --> 00:34:38,719 Speaker 1: hood and dumping it into the engine. Um, you know, 622 00:34:38,800 --> 00:34:41,560 Speaker 1: things are not nearly as targeted as they as we 623 00:34:41,640 --> 00:34:44,200 Speaker 1: want them to be. Yeah, that's great, that's a good metaphor. 624 00:34:44,920 --> 00:34:47,200 Speaker 1: So I want to cite a few claims a few 625 00:34:47,200 --> 00:34:50,640 Speaker 1: other claims about induced neuroplasticity and adult humans that have 626 00:34:50,640 --> 00:34:53,919 Speaker 1: appeared in the press. One is one what I've seen 627 00:34:53,960 --> 00:34:57,440 Speaker 1: referenced a lot is a article and New Scientist by 628 00:34:57,440 --> 00:35:01,560 Speaker 1: Helen Thompson about neuroplastics, city drugs, And one of the 629 00:35:01,600 --> 00:35:05,239 Speaker 1: research teams that Thompson talks about is led by the 630 00:35:05,640 --> 00:35:10,120 Speaker 1: Harvard Professor of Neurology, Takeo. Hinch, who's been doing one 631 00:35:10,239 --> 00:35:12,560 Speaker 1: one line of research, and the basic gist is that 632 00:35:13,360 --> 00:35:16,799 Speaker 1: one of the physiological changes that appears to close the 633 00:35:16,840 --> 00:35:20,880 Speaker 1: window of neuroplasticity and children and bring on this period 634 00:35:20,920 --> 00:35:24,640 Speaker 1: of adult neuro stability is the proliferation of a particular 635 00:35:24,880 --> 00:35:28,759 Speaker 1: enzyme in the brain, the enzyme histone D A claise 636 00:35:28,920 --> 00:35:31,839 Speaker 1: or h d A C. And according to Thompson, this 637 00:35:32,040 --> 00:35:37,400 Speaker 1: enzyme primarily serves to inhibit the activation and deactivation of 638 00:35:37,520 --> 00:35:39,880 Speaker 1: genes in our DNA, so we know that genes and 639 00:35:39,920 --> 00:35:42,040 Speaker 1: the DNA. It's not like all the genes are all 640 00:35:42,120 --> 00:35:45,040 Speaker 1: doing their thing all at the same time. Genes can 641 00:35:45,040 --> 00:35:49,200 Speaker 1: be activated and deactivated, turned on and turned off, and 642 00:35:49,360 --> 00:35:52,560 Speaker 1: apparently the proliferation of the enzyme h D a C 643 00:35:53,160 --> 00:35:56,359 Speaker 1: prevents this turning on and off. It's like, okay, settle down, 644 00:35:56,800 --> 00:35:59,719 Speaker 1: stop flipping the switches. So if this enzyme is a 645 00:35:59,800 --> 00:36:02,799 Speaker 1: so seated with the end of the neuroplasticity window, what 646 00:36:02,840 --> 00:36:06,239 Speaker 1: if we could simply inhibit this enzyme right, would plasticity 647 00:36:06,360 --> 00:36:09,360 Speaker 1: open back up? So in two thousand ten, Hinge and 648 00:36:09,480 --> 00:36:12,600 Speaker 1: colleagues found found this to be the case in rodents 649 00:36:12,600 --> 00:36:15,719 Speaker 1: at least. They used a drug called valproate, which is 650 00:36:15,760 --> 00:36:18,759 Speaker 1: a drug that specifically restricts his stone d C LAS 651 00:36:18,840 --> 00:36:21,440 Speaker 1: or h D a C, and usually valparade is used 652 00:36:21,440 --> 00:36:24,799 Speaker 1: to treat conditions like epilepsy and bipolar disorder. In this case, 653 00:36:24,800 --> 00:36:28,960 Speaker 1: it appeared to cure amblopia in adult rodents, which is 654 00:36:29,000 --> 00:36:31,560 Speaker 1: often caused by reduced sight in one eye during the 655 00:36:31,600 --> 00:36:34,360 Speaker 1: period in childhood when the senses are developing. If you 656 00:36:34,360 --> 00:36:37,759 Speaker 1: don't fix it during that neuroplastic window in childhood, you're 657 00:36:37,840 --> 00:36:40,239 Speaker 1: usually stuck with it as an adult. Yeah, and this 658 00:36:40,280 --> 00:36:42,360 Speaker 1: is something that played into some of those twentieth century 659 00:36:42,560 --> 00:36:47,320 Speaker 1: uh uh discoveries related to plasticity that I referenced earlier. Yeah, 660 00:36:47,320 --> 00:36:49,879 Speaker 1: but would this kind of thing actually work in humans? 661 00:36:49,880 --> 00:36:52,680 Speaker 1: So Hinge work together with Alan Young at King's College, 662 00:36:52,680 --> 00:36:55,280 Speaker 1: London and some other colleagues to see if this drug 663 00:36:55,280 --> 00:36:58,600 Speaker 1: could allow adults to acquire a skill it's usually only 664 00:36:58,640 --> 00:37:02,279 Speaker 1: acquired during that highly plastic period of childhood. And they 665 00:37:02,320 --> 00:37:06,359 Speaker 1: went with perfect pitch again uh, calling out that that 666 00:37:06,440 --> 00:37:09,279 Speaker 1: note knowing exactly what the note is not relative to 667 00:37:09,320 --> 00:37:11,680 Speaker 1: other notes, but just hearing it or being able to 668 00:37:11,719 --> 00:37:14,640 Speaker 1: produce it. So they did a study with twenty four 669 00:37:14,640 --> 00:37:17,759 Speaker 1: men who had no perfect pitch, no musical training, and 670 00:37:17,800 --> 00:37:20,720 Speaker 1: these men were treated with either valperoid or placebo daily 671 00:37:20,800 --> 00:37:23,040 Speaker 1: for about two weeks, and during the second half of 672 00:37:23,040 --> 00:37:26,120 Speaker 1: the treatment period, they watched training videos on how to 673 00:37:26,200 --> 00:37:30,520 Speaker 1: identify absolute musical tones by associating them with names like 674 00:37:30,680 --> 00:37:33,799 Speaker 1: Sarah and Jimmy. The reason they did names was to 675 00:37:33,880 --> 00:37:37,359 Speaker 1: rule out any potential pre existing associations that the men 676 00:37:37,480 --> 00:37:40,040 Speaker 1: might have with pitches in the note names. But I 677 00:37:40,080 --> 00:37:41,759 Speaker 1: like the idea of it's like you know, sing me 678 00:37:41,800 --> 00:37:44,400 Speaker 1: a middle Jimmy. On the last day of the trial, 679 00:37:44,480 --> 00:37:46,279 Speaker 1: the group was given a test. They had to listen 680 00:37:46,280 --> 00:37:49,040 Speaker 1: to eighteen notes and see if they could correctly identify 681 00:37:49,200 --> 00:37:52,600 Speaker 1: the absolute pitches by name. The control group who took 682 00:37:52,600 --> 00:37:55,319 Speaker 1: the placebo got an average of about three point five notes, 683 00:37:55,400 --> 00:37:58,680 Speaker 1: which was performance at chance. The test group who took 684 00:37:58,719 --> 00:38:01,960 Speaker 1: the valpoid got a little over five notes right on average, 685 00:38:02,000 --> 00:38:05,200 Speaker 1: which was significantly better than chance. So this was a 686 00:38:05,239 --> 00:38:08,520 Speaker 1: small study, maybe kind of small effect, but it caught 687 00:38:08,560 --> 00:38:12,520 Speaker 1: plenty of attention from other from other researchers, and Thompson 688 00:38:12,560 --> 00:38:17,400 Speaker 1: reports that there are also neuroplasticity induction trials with drugs 689 00:38:17,440 --> 00:38:20,640 Speaker 1: like dnepazil, which is used to treat Alzheimer's, or the 690 00:38:20,680 --> 00:38:24,480 Speaker 1: common antidepressant prozac. So you know, of course, you see 691 00:38:24,480 --> 00:38:26,279 Speaker 1: a lot of hype in the headlines like you know, 692 00:38:26,400 --> 00:38:28,680 Speaker 1: learn like a child again, rewire your brain to be 693 00:38:28,719 --> 00:38:32,760 Speaker 1: a super learner. But despite these early, kind of promising 694 00:38:32,800 --> 00:38:36,359 Speaker 1: seeming trials, we should remember to slow down. Even if 695 00:38:36,400 --> 00:38:39,480 Speaker 1: we didn't know anything except the fact that our bodies 696 00:38:39,520 --> 00:38:42,759 Speaker 1: were created by natural selection, we could conclude that the 697 00:38:42,840 --> 00:38:47,400 Speaker 1: brain shuts down it's hyperplastic period for a reason. Do 698 00:38:47,520 --> 00:38:50,520 Speaker 1: we really want to go messing around with the stability 699 00:38:50,520 --> 00:38:53,560 Speaker 1: of our brain without a good reason behind it. Yeah, 700 00:38:53,680 --> 00:38:56,080 Speaker 1: we kind of just trying to solve the lament configuration 701 00:38:56,239 --> 00:38:59,360 Speaker 1: here without any real understanding of what is going to happen. 702 00:38:59,600 --> 00:39:01,799 Speaker 1: So let's take another quick break, and when we come back, 703 00:39:01,840 --> 00:39:06,280 Speaker 1: we will briefly discuss some of the potential downsides of neuroplasticity, 704 00:39:06,400 --> 00:39:11,719 Speaker 1: the pros and cons. All right, we're back, so we 705 00:39:11,719 --> 00:39:15,000 Speaker 1: we we discussed the idea that neuroplasticity could have not 706 00:39:15,120 --> 00:39:19,080 Speaker 1: just pros but also cons. If you extend euro plasticity 707 00:39:19,120 --> 00:39:23,399 Speaker 1: into adulthood, that's not necessarily a perfectly good thing right now. Now, 708 00:39:23,440 --> 00:39:27,160 Speaker 1: certainly that the potential pros are really attractive because we 709 00:39:27,320 --> 00:39:32,200 Speaker 1: could invoke brief widenings of neuroplasticity to aid in recovery 710 00:39:32,239 --> 00:39:36,400 Speaker 1: from various illnesses and injuries. We could treat neurological diseases 711 00:39:36,440 --> 00:39:39,319 Speaker 1: and fight the effects of Alzheimer's. We could also use 712 00:39:39,360 --> 00:39:41,480 Speaker 1: it to treat trauma. One of the things I think 713 00:39:41,480 --> 00:39:44,760 Speaker 1: about is that in his presentation at the World Science 714 00:39:44,760 --> 00:39:46,959 Speaker 1: Festival at the beginning of this panel, ma Con talks 715 00:39:47,000 --> 00:39:50,840 Speaker 1: about how hard it is to retrain people to walk. 716 00:39:51,000 --> 00:39:53,120 Speaker 1: After they've had some kind of like stroke or brain 717 00:39:53,160 --> 00:39:56,440 Speaker 1: injury that damages their motor areas, they forget how to 718 00:39:56,480 --> 00:39:58,400 Speaker 1: walk and they need to learn how to walk again. 719 00:39:59,000 --> 00:40:01,760 Speaker 1: It's really hard for an adult to learn how to walk, 720 00:40:02,360 --> 00:40:04,239 Speaker 1: even if your brain is you know, you're in a 721 00:40:04,280 --> 00:40:08,200 Speaker 1: healing phase, because walking is difficult. It's like a super 722 00:40:08,280 --> 00:40:10,120 Speaker 1: hard thing to learn how to do. You're doing all 723 00:40:10,160 --> 00:40:13,360 Speaker 1: this intuitive math all the time to keep your balance, 724 00:40:13,480 --> 00:40:16,560 Speaker 1: to do everything right. It's not easy, but we learn 725 00:40:16,640 --> 00:40:18,960 Speaker 1: it during this period when our brains are in this 726 00:40:19,080 --> 00:40:23,040 Speaker 1: super learning phase as children. So if if you could say, 727 00:40:23,120 --> 00:40:25,240 Speaker 1: have somebody with a brain injury they need to relearn 728 00:40:25,280 --> 00:40:27,920 Speaker 1: how to walk, and you could reinduce that kind of 729 00:40:28,000 --> 00:40:32,440 Speaker 1: childhood motor learning neuro plasticity, then they could potentially have 730 00:40:32,520 --> 00:40:35,440 Speaker 1: a lot more success and have an easier time getting 731 00:40:35,480 --> 00:40:38,400 Speaker 1: back on their feet and relearning these kinds of tasks 732 00:40:38,440 --> 00:40:41,040 Speaker 1: that we take for granted. But of course the potential 733 00:40:41,080 --> 00:40:44,719 Speaker 1: from misuse and even abuse is obviously high. Here, neuro 734 00:40:44,760 --> 00:40:47,840 Speaker 1: plasticity has already become, as we've discussed, something of a 735 00:40:47,880 --> 00:40:52,120 Speaker 1: buzzword in the realm of supplements and self help and 736 00:40:52,160 --> 00:40:55,719 Speaker 1: we focus again on this Nero definition of neuroplasticity most 737 00:40:55,760 --> 00:40:58,560 Speaker 1: of the time, the idea that neuroplasticity equals good and 738 00:40:58,640 --> 00:41:00,879 Speaker 1: assume that any sort of boost year is a good thing. 739 00:41:01,480 --> 00:41:04,960 Speaker 1: But indeed, what would the downsides to even therapeutic use 740 00:41:05,040 --> 00:41:07,799 Speaker 1: be if someone were to take such a drug unregulated 741 00:41:07,800 --> 00:41:10,120 Speaker 1: to aid and study perhaps or or to work on 742 00:41:10,200 --> 00:41:13,920 Speaker 1: some purely for some purely recreational purpose. You know, what 743 00:41:14,040 --> 00:41:16,880 Speaker 1: would be the cost? We again, we don't know for certain, 744 00:41:17,080 --> 00:41:19,560 Speaker 1: but but there are some possibilities and some of these 745 00:41:19,600 --> 00:41:22,920 Speaker 1: were discussed in that World Science Festival panel. What did 746 00:41:22,960 --> 00:41:25,560 Speaker 1: they talk about, Well, they said, for one thing, there 747 00:41:25,600 --> 00:41:29,399 Speaker 1: is this potential link between too much plasticity and say, 748 00:41:29,440 --> 00:41:33,840 Speaker 1: savant abilities. Uh. Savant syndrome is when individuals with mental 749 00:41:33,880 --> 00:41:38,520 Speaker 1: disabilities exhibit advanced abilities and specific areas such as recall, 750 00:41:38,840 --> 00:41:43,640 Speaker 1: calculation or musical skill. So, under under their characterizations, savant 751 00:41:43,760 --> 00:41:48,080 Speaker 1: syndrome could be sort of a byproduct of of unregulated 752 00:41:48,120 --> 00:41:51,160 Speaker 1: plasticity in the brain. Yeah, or at the very least, 753 00:41:51,160 --> 00:41:53,440 Speaker 1: it's a situation where if you're saying, yeah, give me 754 00:41:53,480 --> 00:41:55,520 Speaker 1: all the plasticity you got, what could go wrong? And 755 00:41:55,560 --> 00:41:59,440 Speaker 1: they're saying, well, Uh, here, here is something. Here's an 756 00:41:59,480 --> 00:42:02,319 Speaker 1: example of a case where they may be linked to 757 00:42:02,320 --> 00:42:06,080 Speaker 1: too much plasticity. Yeah. They also say that too much 758 00:42:06,080 --> 00:42:10,239 Speaker 1: plasticity may yield too much to the environment. Yeah. How 759 00:42:10,280 --> 00:42:14,920 Speaker 1: about um, when children are young, they're emotionally vulnerable. Yeah. 760 00:42:15,040 --> 00:42:16,560 Speaker 1: Or it makes me again think of that v for 761 00:42:16,680 --> 00:42:20,520 Speaker 1: Vendetta example of a character essentially, you know, tormenting himself 762 00:42:20,600 --> 00:42:23,880 Speaker 1: by by taking a psychedelic at a at a place 763 00:42:23,920 --> 00:42:27,920 Speaker 1: of intense historic trauma. Yeah. Now, I can definitely see 764 00:42:27,920 --> 00:42:30,560 Speaker 1: ways that if you were to say, make my brain 765 00:42:30,680 --> 00:42:33,399 Speaker 1: sort of a vessel, make it, make it play. Though 766 00:42:33,600 --> 00:42:36,120 Speaker 1: we can shape it, however, we want the first really 767 00:42:36,200 --> 00:42:38,440 Speaker 1: bad thing to happen to you while you're in that 768 00:42:38,520 --> 00:42:42,359 Speaker 1: state could have really traumatic effects. Yeah, indeed, I mean 769 00:42:42,400 --> 00:42:44,920 Speaker 1: ultimately it can make for a more chaotic system of 770 00:42:45,000 --> 00:42:48,600 Speaker 1: the mind. Uh, in a time, during a time in 771 00:42:48,600 --> 00:42:51,880 Speaker 1: which you're not supposed to have that much chaos. Also, 772 00:42:51,960 --> 00:42:54,520 Speaker 1: they point out that autism may be a situation that 773 00:42:54,640 --> 00:42:58,720 Speaker 1: entails too much neuroplasticity. It's been pointed out that transcranial 774 00:42:58,760 --> 00:43:03,799 Speaker 1: magnetic stimulation looks it works longer on autistic individuals, so 775 00:43:03,880 --> 00:43:08,400 Speaker 1: there is stronger perturbation there and transcranial magnetic stimulation that 776 00:43:08,520 --> 00:43:10,399 Speaker 1: just be where you put like a magnetic coil over 777 00:43:10,440 --> 00:43:13,680 Speaker 1: the head to induce current in the brain, and that 778 00:43:13,800 --> 00:43:17,360 Speaker 1: sort of stimulates certain brain areas or or actually I 779 00:43:17,360 --> 00:43:20,600 Speaker 1: think often suppresses or sort of like shuts down certain 780 00:43:20,640 --> 00:43:24,360 Speaker 1: brain areas. But they're saying that in certain in certain cases, 781 00:43:24,400 --> 00:43:27,760 Speaker 1: it appears that some individuals with some types of autism 782 00:43:27,800 --> 00:43:31,719 Speaker 1: are more susceptible to the brain being manipulated by that 783 00:43:31,840 --> 00:43:35,040 Speaker 1: kind of thing. Yeah, exactly. And then on the other hand, 784 00:43:35,040 --> 00:43:38,720 Speaker 1: they say that schizophrenia may, according to some recent studies, 785 00:43:38,760 --> 00:43:42,520 Speaker 1: be tied to synaptic pruning again the process by which 786 00:43:42,520 --> 00:43:45,960 Speaker 1: the brain sheds weak connections between neurons. In other words, 787 00:43:46,000 --> 00:43:48,279 Speaker 1: that it might be more associated with the brain sort 788 00:43:48,320 --> 00:43:53,480 Speaker 1: of being the opposite of two neuroplastic to neurostable. Yeah, yeah, again, 789 00:43:53,520 --> 00:43:55,400 Speaker 1: just showing that there is a balance in that there 790 00:43:55,440 --> 00:43:57,480 Speaker 1: seems to be a balance in the brain, and we 791 00:43:57,560 --> 00:43:59,759 Speaker 1: really need to know what we're doing before we disrupt it, 792 00:44:00,160 --> 00:44:04,399 Speaker 1: even for very noble purposes and very targeted purposes um point. 793 00:44:04,480 --> 00:44:07,360 Speaker 1: For instance, during adolescence and even early adulthood, we see 794 00:44:07,640 --> 00:44:10,920 Speaker 1: this in the pre frontal cortex, the center of you know, 795 00:44:11,000 --> 00:44:14,800 Speaker 1: thinking and planning skills. People with genes that accelerate or 796 00:44:14,840 --> 00:44:19,480 Speaker 1: at intensify pruning or at higher risk for schizophrenia, according 797 00:44:19,480 --> 00:44:23,640 Speaker 1: to a two thousand sixteen Columbia University study published in Nature. 798 00:44:24,920 --> 00:44:27,759 Speaker 1: And then it's worth driving home too that this would 799 00:44:27,760 --> 00:44:30,640 Speaker 1: in no way be a magic pill. This would not 800 00:44:30,680 --> 00:44:33,120 Speaker 1: be like some some movie pill where you just take 801 00:44:33,160 --> 00:44:36,240 Speaker 1: it and oh, I'm suddenly, uh, you know, a complete genius. 802 00:44:36,280 --> 00:44:39,080 Speaker 1: Suddenly I'm a master of every art I attempt to 803 00:44:39,080 --> 00:44:41,759 Speaker 1: take up. Well, yeah, I mean we should keep in 804 00:44:41,800 --> 00:44:44,160 Speaker 1: mind we don't want to overstate the effects too much, 805 00:44:44,160 --> 00:44:46,640 Speaker 1: are over generalized too much. But with the caveat that 806 00:44:46,680 --> 00:44:50,640 Speaker 1: this is just a metaphor, you should be careful about 807 00:44:50,680 --> 00:44:53,799 Speaker 1: anything that makes your mind more like the mind of 808 00:44:53,840 --> 00:44:57,000 Speaker 1: a child. Yeah, that makes your mind more like I mean, 809 00:44:57,040 --> 00:44:59,399 Speaker 1: there are great things about being a child, but there 810 00:44:59,400 --> 00:45:01,960 Speaker 1: are also ways in which being a child is a 811 00:45:02,040 --> 00:45:05,880 Speaker 1: position of vulnerability. There's a reason we protect children, yes, 812 00:45:06,360 --> 00:45:08,520 Speaker 1: And who's going to protect you if you're you know, 813 00:45:08,640 --> 00:45:14,200 Speaker 1: if you're taking a whole bunch of illegally obtained neuroplasticity pills, 814 00:45:14,239 --> 00:45:16,600 Speaker 1: Like there's there's not a direct comparison to be made 815 00:45:16,600 --> 00:45:22,640 Speaker 1: here between say potential neuroplasticity drug abuse and say steroid abuse. 816 00:45:23,120 --> 00:45:25,680 Speaker 1: But but but I think you can you can draw 817 00:45:25,719 --> 00:45:29,080 Speaker 1: some very rough comparisons. You know, an individual who who 818 00:45:29,120 --> 00:45:32,319 Speaker 1: takes too much of this substance in order to artificially 819 00:45:32,360 --> 00:45:36,560 Speaker 1: bulk up muscles in an in what is ultimately an 820 00:45:36,600 --> 00:45:39,200 Speaker 1: unhelpful way, you know, like muscles that are too big 821 00:45:39,239 --> 00:45:41,759 Speaker 1: to really function for what you you need them for, 822 00:45:42,160 --> 00:45:46,280 Speaker 1: and then that occurring with with various side effects as well, 823 00:45:46,880 --> 00:45:51,120 Speaker 1: both mental and physical. So I feel like we we 824 00:45:51,120 --> 00:45:55,320 Speaker 1: we risk similar situations, certainly if we're talking about any 825 00:45:55,600 --> 00:45:59,239 Speaker 1: future abuse of these or even just recreational use of 826 00:45:59,280 --> 00:46:02,080 Speaker 1: neuroplastics the drugs, As is often the case with with 827 00:46:02,200 --> 00:46:05,680 Speaker 1: great possibility for rewards comes great possibility for risks. So 828 00:46:05,800 --> 00:46:08,600 Speaker 1: this is this is something where you should keep an 829 00:46:08,600 --> 00:46:10,960 Speaker 1: eye on it. This is a field that could have 830 00:46:11,040 --> 00:46:14,359 Speaker 1: great promise for really helping people's lives. But but you know, 831 00:46:14,440 --> 00:46:16,719 Speaker 1: be careful, don't buy into the hype, and definitely don't 832 00:46:16,760 --> 00:46:20,319 Speaker 1: buy anything somebody selling. Yeah, yeah, be care because there, 833 00:46:20,640 --> 00:46:22,600 Speaker 1: as was pointed out there, there are already products in 834 00:46:22,600 --> 00:46:26,160 Speaker 1: the market that are using vineero plasticity buzzword to to 835 00:46:26,160 --> 00:46:28,520 Speaker 1: to reach you. Uh. And at the same time, if 836 00:46:28,520 --> 00:46:31,760 Speaker 1: you're thinking, well, Robert, Joe, I'm getting a little older, 837 00:46:31,800 --> 00:46:34,040 Speaker 1: and I want to I want to stay sharp. I 838 00:46:34,080 --> 00:46:36,759 Speaker 1: wanna I want to do what I can to to 839 00:46:36,880 --> 00:46:39,680 Speaker 1: keep those doors a little bit wide. I want to 840 00:46:39,840 --> 00:46:42,400 Speaker 1: I don't want to go into neural stagnation. What can 841 00:46:42,440 --> 00:46:44,560 Speaker 1: I do? Well, there are safe things that we do 842 00:46:44,640 --> 00:46:47,720 Speaker 1: know about. In fact, there is one of them is sleep, 843 00:46:48,400 --> 00:46:54,120 Speaker 1: getting plenty of sleep, exercise and nutrition. Uh. Using your brain, 844 00:46:54,440 --> 00:46:59,480 Speaker 1: like stimulation of the brain, both intellectually and socially. Yeah, 845 00:46:59,520 --> 00:47:01,799 Speaker 1: and you know your you might think, well, these don't 846 00:47:01,800 --> 00:47:05,880 Speaker 1: sound very fun, but I hate stimulated. It's like you 847 00:47:06,040 --> 00:47:07,840 Speaker 1: like keep telling us to take our vitamins. But in 848 00:47:07,920 --> 00:47:09,640 Speaker 1: a way, it's like that. It's like we're not talking 849 00:47:09,640 --> 00:47:12,360 Speaker 1: about magic fixes here, but we're talking about things that 850 00:47:12,360 --> 00:47:14,400 Speaker 1: that that have done regularly over the course of a 851 00:47:14,440 --> 00:47:16,799 Speaker 1: lifetime have been shown to have positive effects. Why can't 852 00:47:16,800 --> 00:47:19,480 Speaker 1: I just have a pill? I know that's that's what 853 00:47:19,600 --> 00:47:22,239 Speaker 1: we really want. But but I do think when you 854 00:47:22,280 --> 00:47:24,560 Speaker 1: when you look at it, like more often than not, 855 00:47:24,600 --> 00:47:28,080 Speaker 1: it's certainly with more complex things related to human physiology 856 00:47:28,120 --> 00:47:31,880 Speaker 1: and and and certainly the mind the quick fixes is 857 00:47:31,920 --> 00:47:34,360 Speaker 1: not necessarily what we think it is. Yeah. Now, I 858 00:47:34,440 --> 00:47:35,920 Speaker 1: want to come back on what I just said there. 859 00:47:35,920 --> 00:47:39,360 Speaker 1: I am certainly not somebody who wants to demonize medication 860 00:47:39,400 --> 00:47:43,160 Speaker 1: of any kind, demonized psychiatric medication or or you know, 861 00:47:43,280 --> 00:47:47,479 Speaker 1: neurological medication. I that's a thing you sometimes hear people, 862 00:47:47,520 --> 00:47:49,440 Speaker 1: do you know, like oh, why don't you just you know, 863 00:47:49,640 --> 00:47:51,200 Speaker 1: you need a pill for that? Why don't you just 864 00:47:51,200 --> 00:47:55,040 Speaker 1: whip your life into shape? That That is a fatally 865 00:47:55,880 --> 00:47:59,320 Speaker 1: reductionist st atitude that does not properly understand the way 866 00:47:59,400 --> 00:48:02,320 Speaker 1: that our body and behaviors are controlled by chemicals in 867 00:48:02,360 --> 00:48:05,000 Speaker 1: the brain. Yes, and certainly all the various differences from 868 00:48:05,080 --> 00:48:08,600 Speaker 1: brain to brain. Uh. Yeah, So so I'm very much 869 00:48:08,600 --> 00:48:11,000 Speaker 1: in the same same boat. I think that the future 870 00:48:11,080 --> 00:48:13,959 Speaker 1: for neuro plasticity is bright. There there is a lot 871 00:48:14,000 --> 00:48:16,520 Speaker 1: of good that is going to come of these future 872 00:48:16,520 --> 00:48:19,840 Speaker 1: treatments and medications. But it does benefit us to to 873 00:48:20,040 --> 00:48:24,560 Speaker 1: understand uh, what we're actually talking about and the the 874 00:48:24,560 --> 00:48:28,239 Speaker 1: the both negative and positive potential of the technology. Yeah, 875 00:48:28,560 --> 00:48:32,000 Speaker 1: so hold hold the hype, listen to the researchers. All right, 876 00:48:32,200 --> 00:48:34,759 Speaker 1: So there you have it. Uh. In the meantime, if 877 00:48:34,760 --> 00:48:36,320 Speaker 1: you want to check out more episodes of Stuff to 878 00:48:36,320 --> 00:48:37,799 Speaker 1: Blow Your Mind, head on over to stuff to Blow 879 00:48:37,840 --> 00:48:39,279 Speaker 1: your Mind dot com. That's the mother ship. 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