Listen in to hear how nostalgic thoughts can be a method of physical pain relief, the recent progress made in the effort to one day upload our minds to the digital world, and how getting nanoplastic out of our drinking water could be as simple as sand!
Memories can be pain free.
Digital thoughts.
Water without plastic.
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Find episode transcripts here:https://curiosity-daily-4e53644e.simplecast.com/episodes/nostalgia-blocks-pain-uploaded-brains-sand-vs-nanoplastic
[SFX: MUSIC IN/WOOSH]
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 nostalgic thoughts can be a method of physical pain relief, the recent progress made in the effort to one day upload our minds to the digital world, and how getting nanoplastic out of our drinking water could be as simple as sand!
CALLI: Without further ado, let’s satisfy some curiosity!
[SFX: WOOSH]
CALLI: Nate, I heard you listening to Smash Mouth earlier...
NATE: “Walkin’ on the Sun”, yeah, an old classic. You know, I’ve been thinking about nostalgia lately. I just learned that nostalgia might actually be able to lessen physical pain.
CALLI: There are very few things that make me feel better than another late nineties hit about the big yellow orb at the center of our solar system, Len’s “Steal My Sunshine.”
NATE: Love that one too!
CALLI: But nostalgia is a mental feeling, no? I don’t quite understand what you mean about it having an effect on physical pain. Or physical feelings of any kind? How do you even test that?
NATE: With a CHEPS device.
CALLI: CHEPS?
NATE: That’s right. It stands for Contact Heat-Evoked Potential Stimulator. It’s basically a metal device that applies heat to your skin for testing pain levels.
CALLI: I don’t think I would’ve signed up for whatever study you’re about to describe no matter how many Mariah Carey songs I got to listen to.
NATE: Calli, it’s not so bad! Just a little heat on the forearm, enough to feel some pain, but no harm was done. That would be unethical.
CALLI: Right, of course. Okay, maybe I could do it.
NATE: Well, luckily the researchers were able to gather a group of thirty-four brave souls, ages eighteen to twenty-five, for the experiment. One group of subjects were shown specific nostalgic images while the CHEPS device levels were changed, and the subjects reported on how much pain they felt. This was then contrasted with a second group who were shown a matching set of images - toys, candy, cartoons - but all of these images were from the present day.
CALLI: Oh, interesting. So, all childhood stuff, but the first set was designed to evoke personal, childhood memories?
NATE: Yes! The nostalgia group reported lower pain levels when being administered the same amount of heat from the device. And these findings line up with previous studies from 2020.
CALLI: And what did those studies find?
NATE: That writing assignments developed to create nostalgia correlated with lower reported pain levels in both subjects with chronic pain and those who were administered pain in the lab.
CALLI: Interesting. Now, we’re seeing a lot of self-reported results in these tests, but those aren’t always the most accurate...
NATE: The recent studies tried to account for this factor by hooking their subjects up to MRI scanners as well. And in line with the lower pain reports, the two groups also had different brain activity during the tests.
CALLI: Ah, very nice. Some hard evidence.
NATE: Yeah. The nostalgic group saw decreased activity in the left lingual gyrus as well as the parahippocampal gyrus.
CALLI: The parahippo-what?
NATE: The parahippocampal gyrus. Those two gyruses are parts of the brain that may be involved in determining how we process pain. Though, we’re not entirely sure on how important they are to this function yet.
CALLI: So the subjects showed actual, physical decrease in pain.
NATE: That’s what it looks like. There was also some activity in the thalamus. This part of the brain is believed to have a pretty big role in regulating our feelings of pain. During the study - the sections of the thalamus that deal with memory, learning, and how we sense pain were all activated by the nostalgic images. This suggests that the thalamus could be an integral link between nostalgia and the pain-killing effect it’s having.
CALLI: So next time I have a headache I should just throw “Clueless” on?
NATE: It might actually help! The research does come with a grain of salt though as they’ve been conducted only using lower levels of pain. They’re not really sure how the effects would hold up under much more aggressive forms of pain.
CALLI: Where does the nostalgia factor max out?
NATE: No one really knows where the limit is but it’s believed that higher levels of pain would take up more resources in the brain and so nostalgia wouldn’t have as big an impact.
CALLI: That’s a shame. If you have bad pain, it could be worth a try though, activating your nostalgia.
NATE: Another limitation of the study was the age range. The effects of nostalgia on older generations could vary greatly from the younger crowd. There could also be interesting factors to observe when it comes to the distance of the nostalgia memory from present day. Like the variation between a younger individual whose memory is only ten years ago as opposed to someone with a nostalgic memory that’s forty or fifty years old.
CALLI: I know the boost I get from hearing “All I Want for Christmas” is going to be just as strong when I’m ninety.
NATE: And I’m pretty sure the anti-nostalgia I have for ALL christmas music will still hold up.
CALLI: Maybe we’ll both get to be part of a study when we’re that old.
NATE: Who knows - with further studies we might even get to be pain free in our later years with nostalgia-based pain management. The big benefit of these studies is our newfound knowledge on how our brains work in relation to pain levels. There could be practical applications for nostalgia in physical, emotional, and mental health in the future.
[SFX: WOOSH]
CALLI: Nate, have you ever thought about the possibility of uploading your mind to a computer?
NATE: Of course, Calli! It’s such an interesting thing to think about. Could your life continue? Would it be you? Can a computer function like a brain? Would I even know it happened?!
CALLI: It’s definitely a fascinating thing to consider. And you’re not the only one who thinks so. Scientists and researchers are working to answer the question of whether or not we could upload our consciousness to a digital world as we speak. And while there is skepticism, there has already been some success.
NATE: Oh wow, that’s wild. I feel like this idea pops up in pop culture a lot. But, I’ll admit I never understood what exactly is it that gets uploaded?
CALLI: Sure, it comes up in books and TV, even urban legends about Walt Disney, and former Boston Red Sox star Ted Williams, whose head and body really were frozen in hopes of later reanimation... But the idea of uploading your mind is to recreate your consciousness, all the memories, perceptions, experiences, and biases that make you…you…in the digital world.
NATE: But how do you get them out of there? Thoughts, memories, etc.
CALLI: The theory is that if we could scan our brain in great enough detail, we could then upload it into a computer simulation that would reconstruct your personality and consciousness. It's called “Whole Brain Emulation.”
NATE: Scan the brain? Would you sit in a CT scanner for…a year?
CALLI: Oh you’d need a way more detailed scan even than that. Think scanning each individual neuron, all 86 billion of them and the synapses that connect them, around one hundred TRILLION of them. There are many researchers who think it’ll never be possible. One guessed it would take 10 years to scan a single brain, even if you had a million electron microscopes working at the same time.
NATE: Sounds pretty unlikely then.
CALLI: Sure, for now. If we were to succeed, the scan produced would be called a connectome.
NATE: Too bad we won’t likely see one.
CALLI: Well actually, researchers have already made one….
NATE: Wait but…
CALLI: Not of a human. Scientists have successfully made a connectome of a roundworm. Roundworms are much simpler than humans. They only have 302 neurons in their brain compared to our millions. After producing a roundworm connectome, scientists at the OpenWorm project, as it is called, then installed this connectome into a LEGO robot.
NATE: A sentient LEGO?
CALLI: Interesting you say that. It’s up for debate whether it is sentient, but researchers say, with the connectome installed, the robot had the same sensory and biological action as the real thing. It moved away from touch and moved toward food.
NATE: So then we are on! We are going to live forever Calli! We get to hang out until the end of the universe! The end of time itself!
CALLI: Hold your cyber-horses there Nate. There is a lot of skepticism around all this. The human brain is incredibly complex. While some popular figures like Elon Musk think it will happen eventually, remember, there are other researchers who don't believe we will ever be able to get a detailed enough scan of our brain, let alone be able to reproduce it!
NATE: The other question I am left wondering about, though, is something we mentioned earlier. After all this, would it even be you?
CALLI: Right. Is a copy of your consciousness still you? Or is it just a replication that would go on living a brand new “life”? Does it matter, though, if the first you is gone? Is artificial intelligence conscious? What does it mean to be human at all? We just don’t really know.
NATE: Well maybe if I get myself frozen, my brain can be around long enough to learn the answer to these questions.
CALLI: There are companies out there that say they could do that for you, but for now, I’m gonna appreciate the you I know for sure.
NATE: Calli, you can’t truly be sure we aren’t already brains in jars.
CALLI: Whoa...
[SFX: WOOSH]
NATE: Calli, do you remember that study revealing that hot liquids can dissolve some plastics, like those in coffee cups?
CALLI: Yes! And nanoplastics are so small that most microscopes can’t even see them, right?
NATE: Exactly. But I have some good news. Researchers recently published a study in the Journal of Hazardous Materials that showed that even if untreated water has a huge amount of nanoplastics, those particles can be removed by simple sand filters during water treatment!
CALLI: Oh yeah! Sand filters! …remind me how those work again, Nate?
NATE: Well first, let’s circle back on nanoplastics. If you remember, these are pieces of plastic that are even smaller than microplastics. So small you can’t see them with the naked eye. They’re only 20 or 30 nanometers across, which means you’d need about 3,000 of them to be as wide as a human hair! That’s small enough that they might even be able to enter our body’s cells!
CALLI: And scientists aren’t sure what they might do to us, correct?
NATE: Right, which is why being able to get them out of our drinking water would be incredible! And that’s where the sand filters come in.
CALLI: Right, so is it just…sand?
NATE: Sand, gravel, or something similar. The grains of sand themselves have these tiny pockets that dirt and other particles, like nanoplastics, can get stuck in. We pour the water through the sand slowly, and the water moves through but the particles get stuck! It’s a simple system, and we can even easily clean it out by forcing water through it the opposite direction to push the particles out and refresh the filter.
CALLI: That’s so interesting! But how effective are they? Especially with things as tiny as nanoplastics.
NATE: Researchers were recently able to filter out around 99.9% of all nanoplastics from the water!
CALLI: It doesn’t take a mathematician to see that 99.9% is very close to ALL of the nanoplastics. But I thought it was hard for scientists to even identify nanoplastics in the first place?
NATE: Very hard. So the researchers attached a tiny amount of metal to the nanoplastics to make it easier to track them as they made their way through the sand filter. Once the particles were tagged, researchers could follow the nanoplastics on their journey through the system.
CALLI: Isn’t that how doctors monitor how cancer cells spread in a human body?
NATE: It is, and if this whole process sounds familiar it’s based on that same cancer monitoring technology you’re talking about.
CALLI: And now it's helping us figure out how to limit nanoplastics! But how did they study this? Did they just release nanoplastics into a body of water?
NATE: Researchers put the nanoplastics in water and ran it through sand filters. They tested a few different setups and discovered that as they moved to bigger filters and slowed the flow of water the sand filters did a better job at retaining nanoplastics.
CALLI: Were they able to say just how well the filters worked?
NATE: Their results allowed them to run a VERY complicated set of mathematical tests to accurately predict the behavior of nanoplastics in drinking water treatment facilities. And the best news from the study? The sand worked incredibly well! Think of it! A safe, simple, and incredibly effective way to keep our drinking water clean!
CALLI: Not to be a negative Nancy, Nate, but wasn’t this experiment conducted with metal-labeled nanoplastics? How can we be sure the filtration process will work if we can’t identify the nanoplastics on their own?
NATE: That’s the only part I don’t have a direct answer for, Calli. Researchers say we still need better ways to track nano-plastics without the fancy lab equipment. Even still, it's incredibly good news.
CALLI: Well, I guess I’ll take the good news wherever I can get it, right?
NATE: Definitely, and while there is still work to be done, there are now reasons to be optimistic.
[SFX: WOOSH]
NATE: Let’s recap what we learned today to wrap up.
CALLI: New studies show an interesting link between nostalgia and a reduction in pain levels. When looking at images of objects that bring up nostalgic, childhood memories, people experienced less pain than the control group. Further research on the sections of the brain that control our pain receptors could pave the way for nostalgia-based pain management techniques in future medical practices.
NATE: With detailed enough scanners, we might someday be able to recreate a model of our brain, and upload it to a computer. While the technology is far off—and, to be fair, may never come—researchers and scientists are working towards developing the possibility to put our consciousnesses online.
CALLI: Scientists have made a big breakthrough in getting pesky and hard to see nano plastics out of our drinking water. A new study used a simple sand filtration system to pull out nearly 100% of the nanoplastics. Researchers need to continue to improve the system, but it's a big step to keep these plastics out of our water and our bodies.