TRANSCRIPT

STEMology s1e18

[00:00:00] Intro [00:00:00] David: [00:00:00] Welcome to episode 18 of STEMology

[00:00:02]Sophie: [00:00:02] A podcast sharing some of the interesting fun, and sometimes just patently bizarre news in science, technology, engineering, or maths.

[00:00:11]David: [00:00:11] Your hosts are Dr. Sophie Callabretto and Dr. David Farmer. This week, we are speaking about grassy meat, smelling older

[00:00:18]Sophie: [00:00:18] Mental spirituality and statistical baby talk.

[Grassy Meat

[00:00:22]Grassy mate.

[00:00:23]David: [00:00:23] Grassy meat. Yeah, this week, researchers at the university of bath in the UK have developed an affordable lab system that uses blades of grass to turn cells into cultured meats. AKA, are you ready, Sophie? The grass is always leaner.

[00:00:37]Sophie: [00:00:37] Oh, okay. Yeah. Dave, I hate to tell you this. I just had something coming through from our producer and you’re fired.

[00:00:43] David: [00:00:43] Okay. Amazing. Cool.

[00:00:45]Sophie: [00:00:45] yeah, so I really enjoyed this. So this is my favorite pie. I always have a favorite part of science ever on STEMology, but this is my new favorite part of science ever.

[00:00:54]yeah, so the idea is we’re growing meat and meaty tissues on grass, but they took grass from the [00:01:00]university’s campus. And they used it to create a scaffold, that animal cells can  attach to and grow on. But also, I’m just going to get into the nitty gritty straight up, Dave. That grass is amenity grass suspected to be a combination of rye grass, fescue grass, and doe annual bluegrass.

[00:01:17] And I looked up all those grasses and I could not find anything interesting about them. So that was a shame.

[00:01:24]David: [00:01:24] and for anyone that doesn’t know, amenity grassland refers to grass that is intensively managed, closely lawn grasslands, such as you find in, you know, your park, your local sporting oval, that sort of things.

[00:01:34] Sophie: [00:01:34] Or your university for the purpose of science?

[00:01:37] David: [00:01:37] Exactly. Exactly, exactly. And I love, the way that this came about.

[00:01:41] So there’s a lovely, lovely quote. I’m going to read by the principal investigator,

[00:01:45] Sophie: [00:01:45] Was it Dr. Paul de Bank?

[00:01:47]David: [00:01:47] Dr. Paul de Bank, which is French for Dr. Paul of bank. And what he said was “when we were looking for a scaffold for ourselves, we wanted to find something that was both sustainable and edible. I thought along the lines of a decellularized natural [00:02:00] material, because cellulose, which grass is largely made of is edible, but also because grass has aligned grooves that I hoped would allow the cells to line up together to make fibers we needed.” And here’s the best bit. “And it worked.” Which is something that scientists often don’t get to say “it worked” that sentence could have ended so very differently and no one would have been surprised.

[00:02:23] Sophie: [00:02:23] Like crashed and burned. And we spent a lot of money doing this thing and their results were nothing. Yeah. So I think Dave, from my understanding, part of the challenge in this kind of work was finding a suitable scaffold, right? Cause you need something that the cells can sort of readily attach to and then they need to be able to proliferate and align in a way that precisely mimics fibers of natural tissues, because obviously if we’re growing meat, we need it to grow as meat would. It needs to be cost-effective to scale up and straightforward to manufacture. And then in the instance that we’re making meat, that people can eat in the lab, the scaffold must also be edible to humans.

[00:02:58] So it would be silly to grow it on [00:03:00] something that we couldn’t eat

[00:03:01] David: [00:03:01] it must be edible. Preferably delicious.

[00:03:03] Sophie: [00:03:03] Preferably delicious and grass is edible. Maybe it’s not highly digestible, but like that doesn’t really matter. And that’s because,  we don’t have the right enzyme to digest grass but it actually stimulates the work of the intestines and helps with digestion as a lot of fibers do.

[00:03:18] So that’s also like very helpful, but the quote I thought you were going to go with, which was my favorite was ” When we eat beef, we’re partly eating the grass the cows have grazed on in their lifetime. What’s neat about our study is that it shows that we can directly replace the animal with the grass they ate.”

[00:03:32] David: [00:03:32] We’re cutting out the middle cow.

[00:03:34] Sophie: [00:03:34] Exactly. That was also Dr. Paul de Bank.. So anyway, Dave, let’s get back to this story. So what they did is they took these grass blades from the university and they emptied them of their, natural cells. So this is a process known as decellularization, and that decellularization takes one to two days and they sort of do things chemically.

[00:03:51] But then I dunno if you look to the picture in the paper, Dave, so what happens is decellularized grass is  kind of visually translucent is how they describe it.

[00:03:59] David: [00:03:59] ghost [00:04:00] grass.

[00:04:00]Sophie: [00:04:00] But to me, it looked like they had tiny lab animals, like toilet paper in the lab. Like, did you see it? Cause it’s like, when you look at it as grass like you can tell it’s grass.

[00:04:08] Cause you can see the fibres-ness of it. But when it’s been decellularized to kind of just looks like these strips of what? And I just imagined like little rats just running out at night time and just like T paying the lab. Like that’s what that picture looked like to me.

[00:04:20] David: [00:04:20] Use us to advance human knowledge with you. We are going to show You

[00:04:23]Sophie: [00:04:23] You didn’t feed us the right food. Um, but yeah, so what they did is they decellularize the grass and then they seeded the blades with cells derived from a mouse cell line. So we using mice as we always do sort of in the beginning. But obviously if we were to turn this into meat we could eat, we would replace it with something like bovine stem cells, unless we wanted to eat mouse meat.

[00:04:45]And then the introduced cells stick to the scaffold surface and they multiply and they form links with neighboring cells. And eventually they grow as a cell mass and they form this sort of new 3d tissue. And so the nice thing about this tissue is we could use it for, as I [00:05:00] said, to eat or they can also grow.

[00:05:03] The idea is to grow human muscle tissue, to sort of repair and replace tissue that’s been damaged or lost through sort of injury or disease and stuff like that.

[00:05:11] David: [00:05:11] Yeah. that’s right. And so this is not the first time that plant tissue has been used. So people have done this with other kinds of plants. They’ve done this with things like apple slices, spinach leaves, bamboo, orchid, vanilla, parsley, wasabi green onion, celery, carrot, broccoli, sweet pepper, persimmon, and jujube.

[00:05:29]So the cells will actually grow differently depending on  the kind of topological features of the material that they’re growing on. So the shapes that they’re growing on and all of these different plants seem to have properties that make them good for growing different kinds of cells, but it seems that grass and what they’ve shown in this paper is that grass is the best for growing myoblasts, which are the cells that turn into muscle.

[00:05:51] And that’s the real advanced in this paper.

[00:05:53] Sophie: [00:05:53] What I really liked was they go into the actual, the structure of the grass and as you said, there are these sort [00:06:00] of aligned grooves that allow the cells to, you know, line up and make fives. And they did some like really cool sort of analysis of the grass surface.

[00:06:08] And so they used something called the ProScan 2000, which is a non-contact surface profilometer  it’s a profile low meter. so that’s an instrument used for the surface texture analysis, and it measures surface topography of a sample to reveal a topological image of the surface. So I was trying to find some information about this and what I accidentally founders Dave we can  buy one on eBay for 3,250 us dollars.

[00:06:34]David: [00:06:34] That’s way cheaper than a tiny humanoid robot.

[00:06:37] Sophie: [00:06:37] Yeah, it really is. then it turned out that depending on the type of profile or materials it uses like vastly different technologies. So sometimes it’s like laser triangulation and sometimes it’s other stuff. So I found I’ve got nothing else to say about it, but yeah, but they had some really cool little plots of like the topography of grass surface, which I was, for some reason, like amazingly fascinating.

[00:06:58] David: [00:06:58] No, they did a really careful [00:07:00] job. And they also, did some histological staining. This is where you put chemicals onto cells that make them fluoresce. If they have particular properties. And basically they put cells on, they put these stains on that showed a, whether the cells were alive and most of them were alive, which is great.

[00:07:15] Well, no, 35% of them were alive, which is not most of them, but it’s a good amount. Apparently that’s a good, solid.

[00:07:20] Sophie: [00:07:20] yeah.

[00:07:21] David: [00:07:21] And, but they also showed, like, as you say, they did this really careful topology stuff, but when you just look at the cells, you can see,  they’re all lined up, their muscle cells, they’re all lined up and they’re glowing blue and that’s great.

[00:07:31] They also did a fun thing. They did my favorite kind of microscopy, which is atomic force microscopy, which is basically, this is a microscope that works by poking things

[00:07:40] Sophie: [00:07:40] Uh, yeah, the

[00:07:40] David: [00:07:40] on atomic

[00:07:42] Sophie: [00:07:42] poker scope.

[00:07:43] David: [00:07:43] Yeah. They’re all pokerscope. Exactly. So it’s basically a microscope and it’s a tiny little force transducer.

[00:07:49] So it measures force and you hover these three atoms breadth above your sample, and then you just lower it over the sample and make up a grid with this thing so that [00:08:00] you build up an image of what the thing is, but it also gives you cool information like how squishy the cell is.

[00:08:04] Sophie: [00:08:04] Ooh.

[00:08:05] David: [00:08:05] And, but you can build up really cool pictures.

[00:08:07] It’s a really, really cool bit of kit.

[00:08:08] Sophie: [00:08:08] But yeah. So what they found was, the adhesions those animal stem cells to the grass surface, as you said, was found to be about 35%, which for this is considered a good result, but they’re hoping to find a way to increase this adhesion. And in fact, they have a new PhD student who will be exploring ways to optimize cell attachment and growth, which is lovely.

[00:08:26]and then the next challenge would be scaling up the process to generate sufficient quantities of both cells and scaffold material in order to produce a significant quantity of muscle tissue. And they bring up something quite interesting, which I think is important. Dave. So in the discussion of making lab meat, they’ve said that in the paper, the texture of food has a significant influence over consumer acceptance. And this will also require further investigation for the adoption of plant-based scaffold in clean meat application, which is true I mean, I’m a big fan of just fake meat as it is. I’m not a vegetarian, but I love a fake meat and some of those textures are way off [00:09:00] and you eat that and you go like, oh, I don’t. I dunno.

[00:09:03]David: [00:09:03] Yeah. Yeah, no, I’m a fan of a beyond burger, but there’s some other ones that are,

[00:09:06] Sophie: [00:09:06] but yeah, and I think it would be more disturbing if it was like actual meat cells and

[00:09:11] David: [00:09:11] weird and slippery. I’m going to eat so much in vitro meat. Going to eat so much of it when it’s ready. And when they’re making hearts and spleens, I’ll take one of those each. yeah, I think this is tremendous.

[00:09:22]Sophie: [00:09:22] Great work. Thank you. University of Bath and your beautifully manicured lawn.

Smelling Older

[00:09:27]Hey Dave, do you know the old people can smell vanilla, just as good as young people.

[00:09:41] David: [00:09:41] I didn’t know that Sophie tell me more.

[00:09:43]Sophie: [00:09:43] Well, so there’s some work that’s come out of the University of Copenhagen. And, you know, as we age Dave, all of our senses decline a little bit, and it turns out that perhaps our sense of smell is slightly more complicated than previously thought.

[00:09:57] And we don’t have a broad [00:10:00] decline in our sense of smell. It might actually be a bit more odor specific.

[00:10:04]David: [00:10:04] Yes. So this is some work showing that people seem to lose the sense of smell to smell things which are kind of, Umami like fried meat and onion and mushrooms and things. But there’s absolutely no difference when you get older and smells like Curry, vanilla, cinnamon, bacon coffee, and orange, which are non Umami smells.

[00:10:25] Well, they make a big deal about this Umami thing, but I think that’s because that’s the only thing that they can think of that would explain this difference.

[00:10:31]Sophie: [00:10:31] They sort of suggest that though, and they’re kind of guessing there, but yeah. So this is, some interesting work. I did feel good after having read this, because I really love the smell of vanilla and the idea that until I die, I’ll be able to smell vanilla just like a young man is a very appealing to me.

[00:10:45] But yeah. So what they did is they got a group of, older dames, and they tested their ability to perceive everyday food odors. So their test group was 251 people between the ages of 60 and 98. And then they also had the younger control [00:11:00] group of 92 people between the ages of 20 and 39.

[00:11:04]Basically, my favorite thing here was Dave is they got a bunch of smells and these food odors were preselected for meal plans delivered by a catering company, supplying older adults with meals.

[00:11:14] David: [00:11:14] Lovely. That’s very relevant. That’s a really nice optimization.

[00:11:18] Sophie: [00:11:18] Yeah. and what they did is they created these sniffing sticks and

[00:11:21] that’s not me paraphrasing. It was a snippet. Right.

[00:11:24]David: [00:11:24] It says in the paper, the food orders were presented by means of sniffing sticks way to go on the branding there guys. Thank you so much. It’s just fabulous.

[00:11:32]Sophie: [00:11:32] and they had two types of sniffing sticks. So you had your moderate odor intensity sniffing stick and your strong odor intensity sniffing stick. and then they had, 14 multicomponent food odors and one pure odorant. So the multi-component food odors, just in case anyone was interested because I definitely was, asparagus bacon, banana, cinnamon, coffee, Curry, fried meat, mushroom onion, orange, raspberry, thyme, toasted bread, and vanilla, and the pure odor it was rose, [00:12:00] which is nice.

[00:12:00] And yeah. And what they found, as you said, was it was these kind of umami type odors that they found this decline in and they thought it had something to do with the loss of taste of salty things. Right.

[00:12:12] David: [00:12:12] Yeah, I think you’re right. So I do just have to say before we move on from the methodology, I love this too, well, one more thing about sniffing sticks was sniffing sticks were presented to the test person one by one by a trained experimenter, specifically a trained experiment. We don’t let anyone just touch the sniffing sticks.

[00:12:28]Sophie: [00:12:28] They can’t touch them. They can’t put them near people’s face without at least, you know, several courses in a sniffing stick presentation.

[00:12:35]David: [00:12:35] Not until you put in 20 supervised hours on the sniffing sticks are you allowed to conduct an experiment? So Yeah. they decided that it might be differences in salt taste. And I wonder this too, because, you know, when they talk about like sweet things and how we love sugar and why do we love sugar?

[00:12:50] Because it’s actually not that good for us. And one of the hypotheses about that is that sugar is something that we can taste that is associated with [00:13:00] vitamins. We need vitamins to be healthy And things like fruits that are sweets tend to have vitamins. So  taste the sugar and we think, oh, great sources of vitamins. And that’s one of the ideas about why we eat sugar.

[00:13:10] And I wonder if this is something similar, like, because we need salt, we need to regulate our salt balance in our body. a lot of people might not realize this, but salt balance in the body is very important for the functioning of your cells because cells needs salts to work, and the amount of salts you have in your body is very, very closely related to the amount of fluid that’s in your body at any one moment and how thirsty you are and how much you need to pee and what your kidneys are doing. And all these things are very complicated and interrelated. So the need to regulate salt is actually very, very important to your physiology just working. And I wonder if, something is happening as you age is changing your preference for salty things, maybe this smell thing is some component of that.

[00:13:49] Sophie: [00:13:49] yeah, cause I mean, there was something in the paper that sort of said vaguely that it’s widely recognized that salty is the basic taste most affected by aging and [00:14:00] because you’ve got this sort of strong association between taste and smell, perhaps that is why you then can’t really smell the salty umami things anymore, but that doesn’t actually explain why then salty is the basic taste most affected by aging.

[00:14:13] So what you said like makes perfect sense, right?

[00:14:15] David: [00:14:15] Well, the other thing I wonder as well is like one thing they didn’t look at was blood pressure. And so as your salt levels change over time and as your fluid balance. So basically if your fluid regulation is a bit off, you can become hypertensive. And that may be a reason why people are hypertensive.

[00:14:30]So what I wonder is if you looked at this change in, preference for umami things, does it show any correlation with the blood pressure of the individual? And if so, it might suggest something about what’s happening with them disease wise and hypertension wise.

[00:14:44] Sophie: [00:14:44] Yeah, that’s interesting. Well, I thought this sort of had a nice little conclusion cause they said that they heard that these findings can improve meals and dining experiences for older adults because they go into the sort of the figures a little bit. And they say that 50% of over 65 admitted to Danish hospitals are [00:15:00] malnourished and the same applies to one in five nursing home residents.

[00:15:03]I think that there’s one thing that we haven’t quite touched on yet. So this declining sense of smell had nothing to do with the liking for that particular scent. So they were saying that even though, you know, we use Fried onions and mushrooms as an example

[00:15:16] so that was like most highly affected. But then they quizzed everyone and said, you know, what smells do you like as well? And that didn’t particularly change. And so, um, I don’t know.

[00:15:26]David: [00:15:26] Yeah.

[00:15:26] really fascinating. I also loved, so they looked at lots of things. So the questionnaire they asked about how strongly they could smell and how much they liked the smells they were smelling. They looked to everything they included in the questionnaire, age, gender, civil status. Help relate it to household for older adults, smoking habits and use of medication and dental status.

[00:15:44] So, I mean, they could have found anything. This could have been so awesome. The story could have been married. People hate the smell of bacon. It could have been the tooth. It could have been the toothless love cinnamon. It could have been so many things, but what we’ve got is the aged love vanilla

[00:15:56]Sophie: [00:15:56] yeah, and good. I look forward to growing old now.

Spiritual Brain

[00:15:59]  [00:16:00]David: [00:16:09] So Sophie, some neuroscientists at Brigham, possibly Brigham and Women’s hospital in Boston have literally found religion.

[00:16:16]Sophie: [00:16:16] Yeah. Right. In your brain noggin. specific brain circuit in your brain noggin.

[00:16:21] David: [00:16:21] And your brain hole.

[00:16:22]Sophie: [00:16:22] this was really interesting. So this is all related to, brain lesions. I think Dave. So the idea was that, they used a technique called lesion network mapping, which I’m going to need you to talk about in a second, because I have no idea.

[00:16:36]and the idea was they got 88 neurosurgical patients who are undergoing surgery to remove a brain tumor. and these  lesion locations were distributed throughout the brain. So just not in all of these people did not have it in the same place.

[00:16:48]David: [00:16:48] a thousand Roman soldiers, just scattered across the brain.

[00:16:51] Sophie: [00:16:51] It’s just like, you know, plowing through. but what they did is they got these patients to complete a survey before and after the surgery. and they asked them about [00:17:00] spiritual acceptance and then I just want to jump into this particular thing that they use. They use something called the temperament and character inventory or the TCI.

[00:17:10]and I looked that up and it seems very odd. So it’s this sort of personality trait test, which operates with seven dimensions of personality traits. Apparently there are four temperaments in three characters. And what we’re looking at specifically is the character of self-transcendence and then there’s a sub-category in self-transcendence so S T, which is spiritual acceptance. That’s S T3. And they took the questions from there. And it’s, you know, and the questions are things about being directed by a spiritual force or about miracles or religious experiences and purposes. And I tried to find this test on the internet, Dave, I couldn’t, but I found the I PIP equivalent, which is just like a weird website with lots of personality traits.

[00:17:50] And it turns out for spiritual acceptance. I got 42 out of 100 and I don’t know what that means.

[00:17:54] David: [00:17:54] I don’t know what that means either. so spiritual acceptance also just to define it for the listeners is [00:18:00] defined as a stable shift in worldview towards belief and forces cannot be rationally comprehended, or objectively proven. And I also love this. This is in the introduction and I loved it so much.

[00:18:11] There is no accepted standard for measuring  religiosity. Although obviously what you’re describing Sophie is one of the proposed ones, I guess.

[00:18:18]Sophie: [00:18:18] I think they distinguished between spirituality and religiosity. So I think spirituality, they say you can kind of use this, but for like religiosity. Like they don’t have an accepted way to measure that, but they’ve sort of linked the two, I think

[00:18:31]David: [00:18:31] so yeah. so they say there is no accepted standard for measuring religiosity, but it can be assessed by a simple self report to the question. Do you consider yourself to be a religious person? Thanks science. Couldn’t have done it without you. Science. That’s great science. Thank you, Captain obvious Science.

[00:18:47] Sophie: [00:18:47] I use this thing. Yes or no. Yes. Religious tick. Next question. Yeah. So Dave, so that was that we had our 88 neurosurgical patients. They also validated the results using a second [00:19:00] data set made up of 105 patients with lesions caused by penetrating head trauma from combat during the Vietnam war, which is very unpleasant.

[00:19:07]so out of our 88 neurosurgical patients, 30 showed a decrease in self reported spiritual belief. 29 showed an increase. And 29 showed no change at all. And they said that using this particular kind of lesion network mapping, they found that self-reported spirituality matched toy specific brain circuit centered on the PAG, which is, the Peri Aqueductal Gray, which sounds like it needs another verb at the end.

[00:19:33] So Dave what’s happened in this research. Any idea?

[00:19:36]David: [00:19:36] so basically what they’re doing is they’re looking for the seat of spirituality in the brain, which is something that neuroscience has been trying to do for a long time. And they did it with this thing called lesion network mapping, and I had to learn about it. And I think I have a superficial understanding of it, which I shall know lay out for you.

[00:19:50] So what’s really interesting about lesion network mapping is that first of all, you’re looking at brains that have lesions. So you’re looking at people who happen to have had some thing happened to their [00:20:00] brain because experimentally it’s not ethical to cause lesions in people’s brains.

[00:20:04] Sophie: [00:20:04] I would agree.

[00:20:06] David: [00:20:06] Yeah. because people would not agree to it.

[00:20:07] And if they did it, wouldn’t be ethical. And it’s a bad idea. So this is lesion network mapping. So it’s looking at brains that happen to have lesions because we can learn something about what’s happening in the brain from these people, even without just doing an experiment because it’s happened to them already.

[00:20:22] But what’s really interesting about lesion network mapping is that it uses the activity of healthy brain to figure out what’s happening in the lesion brain. So basically they look at this baseline data set, which is made up of, I think, a thousand healthy brain.

[00:20:37] Sophie: [00:20:37] Yeah,

[00:20:38] David: [00:20:38] And they make basically an ideal brain.

[00:20:40] And what they do is my understanding is they look at brain activity at rest and they do what’s called functional connectivity. And this is where you look at different brain regions that fire together. So they can look at the brain and to functional magnetic resonance imaging. And this tells you what regions of the brain are active.

[00:20:57] And they look for regions of the brain that are active together. And if you [00:21:00] find regions of the brain that are active together, they say this forms part of a network because these bits of the brain are always firing together and they average it lots of times so that they can be sure if the results and that’s that.

[00:21:09]So basically when they look at the lesion, they put the lesion into this idea of the ideal brain and they look at where the lesion is, and they look at the parts of the network that would be most likely to be affected across the whole brain, not just where the lesion is.

[00:21:26] Sophie: [00:21:26] Okay.

[00:21:27] David: [00:21:27] And when they did that in these patients, what they found was the region that’s most strongly affected with these measures of religiosity or spirituality was the peri aqueductal gray.

[00:21:37]Sophie: [00:21:37] Which is a brainstem region that has been implicated in numerous functions, including fear conditioning, pain modulation, altruistic behaviors and unconditional love. Is that true, Dave? That sounds like a delightful little part of the brain.

[00:21:50] David: [00:21:50] it’s a very old and very well-preserved part of the brain. It has a lot of them cardiovascular regulatory things to do as well.

[00:21:56] Sophie: [00:21:56] That seems quite important.

[00:21:57]David: [00:21:57] it’s really important. And so it’s a really interesting part of the [00:22:00] brain to find this thing that has so much social importance in such an ancient part of the brain.

[00:22:05]Sophie: [00:22:05] Yeah. and they’ve said that this specific circuit included positive nodes and negative nodes, and it’s basically. The brain lesions affecting either the negative nodes or the positive nodes were the ones that would lead to either. So negative was increased self-reported spiritual belief. And if the brain lesion affected the positive node, that was when they had decreased self-reported spiritual beliefs.

[00:22:30] David: [00:22:30] Yeah.

[00:22:31] So I guess they could say that gave them some more confidence in the results because they could point it both ways.

[00:22:36]Sophie: [00:22:36] Yeah.

[00:22:37]David: [00:22:37] really good papers. I really liked that they did this. They kind of put a limitations section in this paper, which I think is a really good thing for scientists to do.

[00:22:44] And one of the limitations they said is that they didn’t provide rich information about the patient’s upbringing, which can have a big influence when spiritual relief. Also these datasets aren’t massive. I mean, you’ve got a hundred people and 30 of them go one way 30 of them go another way. And 30 of them there’s no change, which sounds a bit [00:23:00] like chance.

[00:23:00]Sophie: [00:23:00] yeah. That sounds like how stats works.

[00:23:03] David: [00:23:03] Yeah.

[00:23:04]they also pointed out the patients in both datasets were predominantly Christian. Although it would be interesting given that it’s such a fundamental brain structure. It would be interesting if this didn’t translate to different spiritual beliefs to me.

[00:23:15] Sophie: [00:23:15] Yeah. And I like the other thing that they bring up is that those lesion locations are associated with other neurological and psychiatric symptoms. and so they’ve said that lesions causing Parkinsonism, intersected, positive areas of this circuit as did lesions associated. Decreased spirituality and then lesions causing delusions and alien limb syndrome intersected with negative regions, which in those negative regions were associated with that increased spirituality.

[00:23:40] But they’ve actually said, overlaps may be helpful for understanding shared features and associations, but these results should not be over interpreted, which I really liked because it said results do not imply that religion is a delusion that historical religious figures suffered from alien limb syndrome or the Parkinson’s disease arises due to our lack of religious faith. Which I think is very [00:24:00] important to say?

[00:24:01] David: [00:24:01] Yes, absolutely. This doesn’t preclude any kind of, deity per se.

[00:24:06] Sophie: [00:24:06] No, but yeah, I thought this was really interesting. And then, also that I got 42% almost spiritual acceptance. And, um, I don’t know if that means Dave.

Statistical Babytalk

[00:24:13] Dave new research suggests that small children learn languages faster than teenagers or adults as a result of the differences in the way that people talk to children and adults, not necessarily the difference between children and adults themselves.

[00:24:36]David: [00:24:36] Yeah. So this is the idea that children learn languages really, really quickly.

[00:24:41] Sophie: [00:24:41] Yeah. And we know

[00:24:41] David: [00:24:41] because yeah, we know this and people assume that’s because there are very, very plastic in the brain and they can learn things very quickly and they’re basically little learning machines and they can do that. And that’s definitely important, but this paper is not about that.

[00:24:54] This paper is about the way that adults speak to their children, specifically [00:25:00] their children in order to facilitate them learning.

[00:25:02]Sophie: [00:25:02] Yeah. So this is some research that’s come out of Carnegie Mellon and so what they actually did was they developed a method to experimentally evaluate how parents use what they know about their child’s language when they talked to them. I thought this was, it was really simple, but it was really fun. I really enjoyed reading this paper to the point that I went to the supplementary material in a really aggressive way, because  I wanted to know what animals they were talking about.

[00:25:26] So what they did, Dave was they got 41 child adult pairs. The children were the children of the adults. So we just didn’t mix and match here. and they got these kids and they put them with their parents in a, well, they’ve caught a naturalistic setting in a lab. So they made it look like a little living room and the kids were aged between two and two and a half.

[00:25:43] And the idea was it was a game so they basically each had an iPad, the parent and the child, and on the child’s iPad, there would be baby picture with three animals. And on the parent’s iPad, it would be the name of one of those animals. And so basically the parents had to help the child pick the specific animal [00:26:00] from the set of three, but using language as a guide. And so what they had was 18 animals. Half of the animals were animals that children would typically know before the age of two. So like, you know, cow and cat and dog and those animals. And then the other half were animals that were typically learnt later and I’ve just really wanted to know what the animals were.

[00:26:17] And I had to go right into the supplementary material. They did this very rigorously. So what they did is they got these parents and it had like an insane list of animals and they had, they actually got them to sort of rate is like a pre-survey to rate vocab knowledge. And then from that they picked these animals, but they messed up slightly.

[00:26:33] So the 18 animals selected were cat, dog, cow fish, bird, duck, horse for their easy animals. And then elephant squirrel, rhinoceros, raccoon, donkey, peacocks. Leopard lobster and Swan for the hard animals. I don’t know if you noticed, but I only said 16 animals and it turns out that pig and rooster, which were originally picked, were accidentally omitted in that pre-survey and so they couldn’t use it.

[00:26:57]I think they still had it in the game, but they [00:27:00] just didn’t use that in terms of the data, but it was really interesting. So they found that parents would leverage the knowledge of their child’s language development to fine tune the kind of information they provided for the kids. And they actually, they got to the point where they, I was going to say quantified or they used words, but there were sort of five different categories of how they would talk to the kid.

[00:27:20] Right?

[00:27:20]David: [00:27:20] Yeah. Yeah. Yeah. So, the big findings seem to be that when the adults played the hard game, which was using the hard animals, the adults would use way more descriptors. So descriptors are, I’m assuming where it’s like a big, small red, fluffy.

[00:27:34] Sophie: [00:27:34] Yeah, So spotted, for example, can you find the spotted leopard if like none of the other animals were spotted?

[00:27:40] David: [00:27:40] So they use that. And then the adults also used more of something else, which I had to look at, which is super ordinate categories, which I think is things like bird, cat,

[00:27:50]it’s like big groups. So if you’re talking about a leopards, then you have to explain that to someone. You have to say things like, oh, well it’s a big spotted cat, which involves descriptors and [00:28:00] super ordinate category.

[00:28:01] Sophie: [00:28:01] So that there had like comparisons, so it’s like a cat and then, you know, then you’re superordinate level category label for peacock would be bird. So yeah, you like, can you find the peacock? You know, it’s a bird, right.

[00:28:13] David: [00:28:13] Yeah. So this is really cool and really rigorous, I think.

[00:28:16] Sophie: [00:28:16] But did you see the other one Dave where they use sub-ordinate level category labels?

[00:28:20] David: [00:28:20] no.

[00:28:21]Sophie: [00:28:21] so ADA, they used just the canonical label. So if they knew like cat you’d like find the cat, then they use the descriptive. Then you have comparison the superordinate level category label, and then the sub-ordinate level category label.

[00:28:32] E.G Limelight Larry, a fictional character from a children’s book. And that was like in Limelight, Larry’s a peacock. So like, can a peacock like Limelight Larry, I looked up  Limelight Larry, just very quickly. And on publishes weekly, I found a review Limelight Larry a peacock, looking forward to having a whole book to himself debuts as a self referential story that offers a continuous string of laughs.

[00:28:54] So that sounds really fun. I think I might go read limelight Larry after this.

[00:28:57] David: [00:28:57] I think you should. I’m glad that it’s self-referential.

[00:29:00] [00:29:00] Sophie: [00:29:00] Yeah. Apparently like he’s a big fan of himself and he’s just making jokes all the time.

[00:29:03] David: [00:29:03] kids love the in joke. They don’t want to have to like read the guardian politics section before they enjoy their kid’s book. It’s got to be inclusive. So this is really cool. so basically what they’re saying is at the start of the paper, they say there’s two kinds of way that children might facilitate speech in their kids. There’s course, which is basically where you change the way that you’re teaching the kids based on, you know, their age or their like their outward developmental appearance.

[00:29:29] And that certainly happens. And there’s evidence for that, but there’s also fine tunings, which is where you specifically teach to your specific child based on your knowledge of how they speak and how they understand. And apparently this paper is the first experimental evidence of that kind of fine tuning that’s been done. Previous to that. It’s only been a couple of observational things, which is an observational study for people is when you just literally observe, you don’t do an experiment, you get some data and you analyze it and you see if you can pick out any trends, but [00:30:00] this is an experiment which gives you a bit more power.

[00:30:02]so I think they’ve done a good job.

[00:30:03]Sophie: [00:30:03] Yeah. And I really enjoyed this paper cause you know, they were very thorough they even said that, you know, we did all this stuff like these, the results, but the participants represented a racial composition similar to the Chicago area and US more broadly.

[00:30:15] So it was  56% white, 27% black and 8% Hispanic, according to the paper. But that then these results do reflect a Western parenting perspective, as well as caregivers with a higher educational background than representative in the country. And so, you know, so there’ve been like, you know, very very thorough  we’ve done this thing, but this is what it represents.

[00:30:34] And also the researchers did not independently measure the child’s knowledge of each animal. So the results of the study can not differentiate whether the child learned any new animals while playing the game, which is fine. Like, that’s not the point. That’s okay, guys, you don’t need to worry about that.

[00:30:46] David: [00:30:46] Yeah, we were really interested in the parents in this particular experiment.

[00:30:50] Sophie: [00:30:50] Hmm on the thing that I thought was sort of quite cool as a bit of a conclusion is that they thought that these results might have some relevance for researchers working in the field of machine learning. Right. So it’s like, you know, [00:31:00] right now when they’re training language models, apparently they just give them all the words at once and maybe it would be a little bit better if we could give the right data at the right time. So I sort of liked the kids, keeping the information at the correct level. And then once they’ve learnt enough, then you can sort of up the complexity, which is interesting.

[00:31:15] David: [00:31:15] See, I wasn’t sure about that. I didn’t think there was enough justification for, I think they threw that in to be sexy and not because it was a good idea and really there was nothing else about it That was an interesting.

[00:31:26] Sophie: [00:31:26] It’s an interesting idea. Well, I quote you know, a lot of the stuff in, um, sort of machine learningis often interesting.

[00:31:31] David: [00:31:31] Yes.

[00:31:32]

[00:31:32]

[00:31:42] Outro [00:31:42] Thanks for listening to another fun episode of STEMology.

[00:31:44]Sophie: [00:31:44] Be to check out the links to all these great stories on our show notes. Go visit www.stemology.com.au. If you have any news you think is STEMology worthy. Drop us an email at stemology@ramaley.media. We’d love to give you a [00:32:00] mention. Your hosts have been Dr. David Farmer and Dr. Sophie Calabretto

[00:32:04]David: [00:32:04] This is a podcast from Ramaley media. Be sure to hit the subscribe button on your favorite listening app so that you never miss our episodes. We look forward to sharing the latest in all things, science, technology, engineering, and maths you the next week and be sure to bring your friends.

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