Today you’ll learn about how archaeologists have found evidence of brain surgery from the Bronze era in the Middle East, how 3D-printed hearts are becoming closer to a reality than ever before, and the recent discovery of how a black hole is eating a dust cloud in space.
Today you’ll learn about how archaeologists have found evidence of brain surgery from the Bronze era in the Middle East, how 3D-printed hearts are becoming closer to a reality than ever before, and the recent discovery of how a black hole is eating a dust cloud in space.
Ancient Brain Surgery
3D Heart
Supermassive Black Hole
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Find episode transcripts here: https://curiosity-daily-4e53644e.simplecast.com/episodes/ancient-brain-surgery-3d-heart-supermassive-black-hole
[SFX: INTRO MUSIC/WHOOSH]
NATE: Hi! You’re about to get smarter in just a few minutes with Curiosity Daily from Discovery. Time flies when you’re learnin’ super cool stuff. I’m Nate.
CALLI: And I’m Calli. If you’re dropping in for the first time, welcome to Curiosity, where we aim to blow your mind by helping you to grow your mind. If you’re a loyal listener, welcome back!
NATE: Today you’ll learn about how archaeologists have found evidence of brain surgery from the Bronze era in the Middle East, how 3D-printed hearts are becoming closer to a reality than ever before, and the recent discovery of how a black hole is eating a dust cloud in space.
CALLI: Without further ado, let’s satisfy some curiosity!
[SFX: WHOOSH]
NATE: Calli, if you had to try and guess how old brain surgery is, what would you go with?
CALLI: I mean, I feel like it's probably something pretty modern. Like a few hundred years, maybe, at best.
NATE: Well, there's evidence that people from places as far away as South America, Africa and beyond, an area we call the ancient Near East, have practiced something called cranial trephination for thousands of years. Now, that term sounds scary, but it's just a medical procedure that involves drilling a hole in the skull.
CALLI: What?
NATE: So it's much scarier than it sounds, especially back then. Like just you imagine. Anyway, it was done for a number of reasons, but it's believed that one of the most common reasons was to alleviate pressure on the brain after a head injury. Now, all that being said, trephination didn't seem to be that common in many parts of the ancient Near East. But a new discovery actually changes that.
CALLI: That is nuts. I can't imagine going through a surgery like that without, like, modern anesthesia anyways. Okay, So. So how how how do they figure this out?
NATE: Rachel Kalisher, a Ph.D. candidate at Brown University's Joukowsky Institute for Archeology in the Ancient World, recently led an analysis on the excavated remains of two assumedly wealthy brothers who lived in the ancient city of Megiddo in Israel, sometime between 1500 and 1401 B.C.. She discovered that shortly before one of the brothers died, someone had performed a specific kind of trephination on him. Angular notched trephination instead of just a straight forward drilling, It involves cutting the scalp in four intersecting lines with a knife that has more of a sloped edge. Then you use a little leverage to create a square shaped hole. We don't know why this guy did it, but there's a similar procedure today called a craniotomy that's used to treat brain tumors or aneurysms.
CALLI: That is nuts. I had no idea this has been going on this long. Is this the oldest known case of trephination?
NATE: No. We actually know about examples of trephination from other parts of the world dating back as far as 6000 B.C. But until recently, it was believed that trephination didn't really take off in the ancient Near East like it did in some other places. If Rachel Kalisher is right, this is the oldest known example of trephination in the area by quite a bit.
CALLI: Okay. If it wasn't common, then why would such an advanced technique be performed on someone in ancient Israel?
NATE: So around 4000 years ago, Megiddo, that ancient city in Israel, controlled part of an important land route called the Via Maria, which connected Egypt, Syria, Mesopotamia and Anatolia. Or, in modern terms, the area from Turkey down to Iraq. Because of that, it was one of the wealthiest, most cosmopolitan cities in the area for hundreds of years. And these brothers were found in a domestic area near Megiddo Bronze Era Palace, which is why it's believed they were elite, wealthy members of society and maybe even part of a royal family. All of this means that they would have been much more likely to receive treatments that were otherwise inaccessible to normal citizens, such as trephination.
CALLI: Interesting. Okay. So do we know why one of the brothers needed surgery?
NATE: Not entirely, but Kalisher does have a few theories. So both brother's bones show minor evidence of iron deficiency anemia during their childhoods, which may have impacted their development. Further evidence for that is that both had a few skeletal abnormalities. For instance, the older brother had an extra molar in one corner of his mouth and an additional cranial suture in the trephination hole, which suggested he might have had some kind of congenital condition. And just in case you've been wondering, no, it was not the trephination that killed the one brother.
CALLI: I wasn't going to say anything, but since you mentioned it, how did the brothers die? Was it their developmental problems?
NATE: It could have been, but that's not what Kalisher thinks. One of the brothers died in his teens or early twenties, and the other sometime between his twenties and forties. Due to the difference in age. She thinks that most evidence points to them dying of an infectious disease. Both brothers’ bones had a number of holes and lesions, as well as some signs of inflammation in the membrane that would have covered their bones. And if you put all that together, you've painted a picture of something like leprosy. But that said, it's nearly impossible to deduce ancient leprosy from bones alone. So Kalisher is working with other researchers to conduct DNA analyzes to figure that out. But no matter what killed them, there's a good chance that the angular, notched trephination was meant to keep the brother alive. But it didn't work. He died within days or even minutes of the surgery, and not because of the surgery, but because the surgery didn't seem to help.
CALLI: Wow. That's kind of a terrifying way to go. But still. Okay. So what's what's the takeaway on all of this?
NATE: So even though there's a lot of new evidence popping up surrounding trephination, there's still so much we don't know. Why are some trephinations around while others are square or even triangular? How common was the procedure in each region and what were people trying to treat? Culture is pursuing a follow up project to try to answer these questions across multiple regions and eras. But right now it's just a huge mystery.
[SFX: WHOOSH]
CALLI: Imagine a world in which you have some kind of debilitating heart problem and your doctor can test a potential treatment directly on your heart without ever having to cut you open. That's a world we're going to be living in soon because of 3D printing.
NATE: In the immortal words of The Princess Bride. Inconceivable. How'd they do this?
CALLI: All right. A professor in mechanical engineering named Ellen Roche created a bio robotic hybrid heart back in January 2020. It's a 3D printed replica of a heart. And I know what you're thinking. How do they know this heart will even work? Well, to make sure the heart works the way it's supposed to, the team also created a sleeve that can make the 3D heart have a heartbeat.
NATE: I mean, I know the expression wear your heart on your sleeve, but I don't think that applies in this situation. What is this sleeve here?
CALLI: Yeah. No, it's not quite like that. You know those blood pressure machines you see at Walmart or CVS? Think of those, except each sleeves bottom looks like bubble wrap. You connect the sleeve to the heart, and then you can change how frequently the air will inflate and deflate the bubbles. Kind of like the badumbadumbadum of a beating heart. The sleeve doesn't go inside of a potential heart recipient. It's used to test the heart before the person receives the heart. Does that make sense?
NATE: Yes, I think so. Okay. Yeah. Proceed with your story.
CALLI: All right. Unfortunately, just a few months after starting their experiment, the lab shut down. In case you didn't notice, this study was happening in 2020. And a little something known as the COVID 19 pandemic was, unfortunately, right around the corner. This didn't stop Roche, though. She had this itch to keep working, so she kept developing the heart and the sleeve at home. Months later, the lab opened again, but due to the work Roche had done at home, the team was actually further along than they were before. So shortly after opening up again, they were able to run the sleeve on a few test models before they expanded to making their research more personal.
NATE: What is personal mean in this context?
CALLI: Well, they wanted each heart and each sleeve to be a personal fit for anyone who needed them. See, it can be hard to even find a proper donor if you need a new heart. No two hearts are entirely alike from person to person. There's different heartbeat rhythms, different sizes and shapes. Not to mention the fact that open heart surgery itself is still a scary surgery. It's not entirely likely, but you can die. Therefore, one size fits all can't really apply with hearts, which is why they turned to 3D printing in the first place. And it's actually pretty simple to see. Step one you create the 3D model out of a person's heart. Step two 3D print the heart using this rubberish polymer based substance that can expand and contract like a normal heart. Step three Test the heart in the sleeve. Step four You've got a new heart.
NATE: Okay, wait a second. This sounds a lot like soft robotics, which we've talked about before, and that's where a robotic part is made up of soft surfaces or thousands of surfaces to emulate more of a soft tissue based feeling, right?
CALLI: Yeah, it's actually a lot like that. I'd argue that it is. What's even better is that this 3D printed, soft robotic heart comes with a 3D printed aorta, the main artery in our bodies that makes blood travel from the heart to the rest of the body. In fact, one of the things that the sleeve can do is wrap around the aorta and constrict it, which sounds counterintuitive, but they do this to imitate the effects of aortic stenosis.
NATE: Well, wait, why? Aortic stenosis is when your aortic valve narrows and it makes your heart have to work a whole lot harder to force blood where it needs to go. Mm hmm. This is a this is a medical problem, not a solution. Why would you want to mimic it?
CALLI: Usually, doctors will treat aortic stenosis by doing surgery and putting in a synthetic valve transplant in order to make an aorta wider. Like any surgery, this can be really risky, especially if you don't have the exact measurements of the valve already. But with a method like this, doctors could test the aortic pump on a 3D printed heart to see which replacement valve would be right. What this means is that they can customize your heart, but they can also test the valves your heart would need.
NATE: That all sounds really good. Does the heart really work.
CALLI: In the lab setting? Yes. But it's still way too early in this project to actually put these into human patients. For now, the team's key focus is using the heart to act as a model to help with other procedures. So, for example, they 3D printed a heart modeled after one of their patients who had undergone an aortic valve replacement surgery. They use this heart to compare different aortic implants to see which one would be too big, which one would be too small, and which one is right in that Goldilocks area and is just right. In short, they were able to identify the exact valve the patient would need without ever having to cut them open.
NATE: I got to say, that does all sound pretty helpful.
CALLI: Honestly, these more patient specific heart replicas can help future researchers develop and identify treatments for people with unique health problems. Not to mention, these replicas could be used by the medical device industry as a means to test therapies for more common heart diseases. Remember that world I told you to imagine the one where doctors can treat your heart without cutting you open. That world is here now.
[SFX: WHOOSH]
NATE: Imagine, if you will, a huge red mass the size of 50 Earths hovering in front of a black hole in the deepest depths of space. Now, imagine that object is getting bigger and bigger every day, and you didn't know why until now.
CALLI: Okay, that was a really ominous intro and I feel like I should be worried.
NATE: I don't know. You don't have to be worried about this. So that object that I'm talking about is X7, and it's on a path orbiting a black hole. And that path is projected to take 170 years. Now, scientists first noticed it over two decades ago. And to the naked eye, it just looks like somebody used the iPhone pen tool to draw a rudimentary line on the sky. It's a strangely straight line in the night sky. And for a long time there was no obvious answer to what it could be. Scientists wondered was it pulled off of a larger structure nearby? Was its weird shape the result of stellar winds? Or maybe it was shaped by particles from the black hole it's near, which is called Sagittarius A no matter what. Every year it got longer and longer until 2023, when astronomers from the UCLA Galactic Center Group proposed that, based on their conclusions from looking at 20 years of data on the anomaly, it's a big old dust and gas cloud.
CALLI: So it wasn't your mom?
NATE: Oh, no. To be fair, it's a cloud of dust and gas that may have happened when two stars collided. And my mother is a star. You're right. Thank you. So even if the payoff is a bit lacking, the way we got here is pretty insane. As X7 has stretched out, it's been pulled apart by Sagittarius A but has remained surprisingly durable. But remember how I said it's supposed to take X7 170 years to finish its orbit of Sagittarius A? That might not actually happen. The researchers are now predicting that if we give it a few decades, X7 will disintegrate and the gas and dust will get sucked into Sagittarius A by the year 2036.
CALLI: Just going to play devil's advocate here for a second. I don't think we really get a choice about whether or not we give it a few decades. That's fair. Yeah. But I am curious as to why.
NATE: Tidal forces, that's the gravitational pulling mechanism that could cause an object approaching a black hole to stretch. See, black holes have what's been described as unimaginable gravity due to how concentrated their mass is. For some perspective, if earth were crushed into a black hole. Our whole planet would be condensed to about one inch across. So whatever side of an object is closest to a black hole is pulled more strongly than the opposite end, and X7 has some similar properties to other weird dusty objects orbiting Sagittarius A. They call these G objects because they look like gas but act more like stars. Now X7's shape and velocity have changed a lot more dramatically than a bunch of the other G objects. This thing is clocking speeds of 700 miles per second and has been stretched across trillions and trillions of miles.
CALLI: Wow. Okay. I know this is a hard question to answer, but has. Has anything like this ever happened or been recorded before?
NATE: Well, like most things in space, we don't really know for sure if it's happened before. But this is the first time that we've seen an object in that region show such a crazy evolution. X7 started off looking a bit like a comet that wouldn't leave the sky. Researchers assumed it got its unique shape from stellar winds or particle jets shooting from the black hole. But the new theory about two stars colliding seems to make the most sense. Stars merging is actually very common, especially near black holes. As stars circle each other, they get closer and closer until they merge, creating a new star hidden in a big old ball of dust and gas. With this theory, the researchers are saying that X7 is the dust and gas thrown away from a merged star that's still out there somewhere and that all of the strange G objects surrounding Sagittarius A are the residual debris from that merger.
CALLI: It still sounds really scary. So we we really do have nothing to worry about?
NATE: It's very far away. There's no worry for us other than just like it bringing up an existential fear of what would happen if we fell into a black hole. The X7 event is nothing for us to worry about. I mean, if anything, it's worth celebrating because we are alive to witness one of the most absolutely unique astral events imaginable. Seeing something impossibly large being destroyed by a black hole and it's visible from Earth. Well, though, it's worth noting that this, unfortunately, isn't something we can see with a normal telescope. It's very hard to watch an object like X7 traveling in the center of our galaxy due to the density of stars, gas and dust, which obscures most activity.
CALLI: Wait, then how are the researchers seeing this?
NATE: Well, they have some pretty high quality equipment at the W.M. Keck Observatory, where this experiment is being performed. They have access to a larger telescope with more detailed resolution instruments that can view things in infrared light and a powerful technology called adaptive optics that removes distortion. Genes that occur naturally when looking through Earth's atmosphere. Plus, they have the privilege to use this equipment around the clock, meaning they always have an eye on X7 and Sagittarius A. The team that discovered this is going to keep monitoring X7 over the next decade and a half and will eventually have as close to a front row seat as is humanly possible for one of the most fascinating yet violent events confirmed to have happened in space.
CALLI: Neat. Space is just neat.
[SFX: WHOOSH]
NATE: Let’s recap what we learned today to wrap up. For years there was no evidence that a form of brain surgery called trephination had been performed during the era of the Ancient Near East. That is, until a researcher found the remains of a pair of brothers, one of whom had evidence of holes in his skull. This teaches us a ton about medical advancements during the Bronze era!
CALLI: New research out of MIT has revealed a functioning 3D printed heart and aorta set that might make heart transplants much easier for doctors moving forward. And since each heart is unique to each patient, it also makes developing treatments easier: you can test specific treatments directly on a beating heart without it ever having to leave the body!
NATE: What’s that big ominous red line inching toward that black hole? Not to worry - it’s a giant gas-and-dust cluster, and when it hits that black hole, it’s going to be violently torn apart! After two decades of mystery, scientists finally believe they’ve figured out the mysterious astral object X7 - and with that discovery, have also realized that we’re going to witness its destruction within our lifetimes!