Today we discuss how the body can physically feel emotions, how axolotls can regenerate their brains, and how pigs can play peacemakers during pig-on-pig fights.
Today we discuss how the body can physically feel emotions, how axolotls can regenerate their brains, and how pigs can play peacemakers during pig-on-pig fights.
Body Map
Brain 2.0
Pig Bystanders
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Find episode transcripts here: https://curiosity-daily-4e53644e.simplecast.com/episodes/body-map-brain-20-pig-bystanders
[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 the body can physically feel emotions, how axolotls can regenerate their brains and how pigs can play peacemakers during pig-on-pig fights.
CALLI: Without further ado, let’s satisfy some curiosity!
[SFX: WHOOSH]
CALLI: So a couple of months ago, a friend had an interesting experience where she went to a reiki healer. It’s a kind of energy healing that hones in on how different emotions present themselves physically in the body.
NATE: Sounds pretty abstract to me. Did she find it worked?
CALLI: Well, she said she definitely felt relaxed after, but that could have also been a symptom of lying down in silence for an hour.
Anyway, I was pretty interested in this very old idea about mind-body connection so I went down a bit of a rabbit hole to see whether or not there’s some modern science to back up the idea that you can physically feel those emotions in the body. And I actually found some very interesting results!
NATE: I love when science explains older healing methods. Tell me what you found!
CALLI: Well, there’s been some recent research into what’s called “body mapping.” Body mapping is basically figuring out where certain emotions are felt physically in the body. According to the scientists, there are 13 emotions related to specific body parts. The mapping process itself kind of works like a heat map where the technology can see how strong a physical reaction to an emotion is, rather than temperature. They came up with a color coding system to gauge how intense these different emotions felt to the subjects.
NATE: Okay, but how do they match the emotion to a specific body part? I feel like that’s not necessarily common sense, right?
CALLI: Well, to create these maps, researchers asked over 700 people to color an outline of a human body with the areas where they felt stimulated during certain situations. And these are real life situations, like seeing a certain facial expression during small talk, for example. After pooling together the results, they found that specific emotions CONSISTENTLY affected similar areas of the body.
NATE: Very cool. What kinds of emotions were they looking for exactly?
CALLI: They broke it down into five categories: negative, which includes things like anger or fear; positive, so things like love and pride; anxiety, or conditions that can control your emotions; homeostasis, which is just feeling neutral and normal; and cognition, which is a state of learning or absorbing information.
NATE: So, let me get this straight. Say someone is having a pleasant conversation and then a researcher goes BOO and scares them, the subjects would then draw where in the body they felt that negative category with the color of intensity the emotion was?
CALLI: Exactly. So if you did that to me right now, for example, and I was really scared, I’d probably feel that emotion in my chest, like a fight or flight response or when you feel like your heart drops. Then because I was REALLY scared, I’d color my chest on the diagram in red because that was used as the color that represents severe emotion.
NATE: Got it. So, what were people feeling the most in the study?
CALLI: It’s actually super interesting because not only could they physically map where these emotions were felt, they could also track just the general timeline of feelings in the participants. Usually, when we think of our emotional journey throughout the day, we think of running through the whole spectrum, right? But during the study, most participants felt pleasant and controlled FAR more often than they felt any negative moods.
NATE: That’s great to hear! But, to play devil’s advocate for a minute: what if I can’t find my emotions? Like if I feel uneasy for no reason at all and don’t know where to place it?
CALLI: In cases like those, where you can’t find the vocabulary or specificity of the emotion, researchers recommend doing something called a mindful body scan. It’s where you slow down and focus to really get a sense of what you’re feeling and why. You can do things like moving your hands and feet gently to help yourself connect to your body and your mood at the same time!
NATE: That’s very cool - kinda like meditation, I guess. But tell me, what is this research even being used for?
CALLI: Well, it’s no surprise that research has found that ignoring or burying emotion might contribute to physical illnesses. This study hopes to emphasize the importance of the mind-body connection so that people can develop a better understanding of emotional disorders like depression or anxiety as well as how to handle overwhelming moods in general.
NATE: So, do you think that this could be a suitable replacement for therapy?
CALLI: Absolutely not! It’s a supplement. One that can help us better understand ourselves, how we’re feeling, and where we’re feeling it. But it doesn’t help paint the picture of WHY we feel the way we do. Mindfulness is the goal here so people should seek out treatment if they need it rather than relying solely on these methods.
NATE: Understood. Do you think after learning about all of this, you might want to go to your friend’s reiki healer?
CALLI: Now that I’m a little more educated and mindful, I just might!
[SFX: WHOOSH]
NATE: Earlier today, I was minding my business, scrolling the internet, when BOOM - a picture of an axolotl hit my eyes. These are these cute little aquatic salamander things that are translucent with little red spikes on their heads. What’s interesting about them though is that they’re able to regrow their entire BRAIN after a head injury!
CALLI: Okay, I actually love those little guys! That’s pretty wild though, I had no idea they can regrow their brain, how did we even find that out?!
NATE: Yep. It was discovered way back in 1964, during an experiment to test the axolotl’s regenerative abilities. You see, we’ve known for a while that they can regrow their limbs if they lose them, or even their hearts or spinal cords. The amount of tissue needed to regrow a limb or organ or even the brain is actually quite small. So, when researchers found that they can do this, it brought up a ton of questions. Like, how effective can the new brain be?
CALLI: I’d say that the regrowth in and of itself is a HUGE success.
NATE: We know that brains have a ton of different cell types, including the cells that connect one part of the brain to the other. They mapped out the cells in an axolotl brain and discovered that the axolotl’s brain regeneration happens in three phases. Phase one begins with a quick increase in progenitor cells, which are cells that can mutate to become other cells depending on what the body needs. In this case, some of the cells start activating the wound-healing process. The cells that aren’t a part of the wound-healing move onto phase 2, where they become neuroblasts.
A neuroblast is a cell that stops dividing and instead starts forming nerve fibers. Basically the beginnings of a nerve cell. Once the neuroblasts are formed, it’s time for phase 3, where those neuroblasts become the kind of neurons that were lost when the brain was damaged in the first place. Summing it all up, cells heal the wound, build nerve fibers and then replace neurons.
CALLI: Such a complex process that you just made so simple. When the new tissue was done reforming, how was the axolotl brain?
NATE: Astonishingly, not that different from before the brain damage. Several neuronal connections that had been wiped out when the brain was hurt were able to reconnect, which implied that the damaged part of the brain could function normally again.
CALLI: This is so wild. Do the researchers have any ideas why an axolotl can do this and a human can’t?
NATE: It has a lot to do with the fact that an axolotl is an amphibian, because that means that they evolved in a very different way from humans. But it turns out, they might not be so far off from humans as we originally thought. They compared the axolotl data with other species and found that the axolotl’s brain waves have a very strong similarity to how a mammal’s hippocampus works, which is the part of the brain involved in memory formation. There were also similarities between a human neocortex and theirs.
CALLI: The neocortex?
NATE: Yeah, the part of the brain known for perception, thought, and spatial reasoning in humans.
CALLI: Wait. So are you telling me that despite the axolotl being an amphibian, its brain has a lot in common with… humans?
NATE: That’s the current theory. The ability to regenerate, as the axolotl does, might actually be an evolutionary remnant of a past connection to mammals. Where exactly we split apart, is not clear. Unfortunately, no matter how similar our brains may be, it appears humans lost the regenerative genes and axolotls kept them.
Scientists are hoping that further experimentation will lead to more effective treatments for severe injuries, not to mention the ability for people to regenerate in a similar way.
CALLI: I wouldn’t have to worry as much about falling off my motorcycle.
NATE: How bad are you at riding your motorcycle?!
CALLI: Listen, we don’t need to talk about it.
[SFX: WHOOSH]
CALLI: Alright, so I’m gonna paint sort of a picture for you here. You’re at a farm, watching three pigs. Two of the pigs are angry as hell and head butting each other and the other pig starts oinking and jumps right in the middle and suddenly, the fight stops and the intervening pig walks off with one of the other pigs. I want you to tell me if I’m describing the really cute scene of a new kid’s movie or the foundation of a new study on the social hierarchy of pigs.
NATE: Ooh, to answer that I’m gonna have to know, are the pigs wearing human-like clothing?
CALLI: Uh, no. No anthropomorphic features whatsoever.
NATE: Alright, in that case, I’m gonna go with scientific study and I’m a little surprised we’re seeing a pig intervening in a fight between other pigs. To me, that sounds like something I thought was strictly a human behavior. Like taxes and flossing.
CALLI: Okay, well, now I just wanna see a pig who can do taxes and floss but that’s beside the point. What you might be surprised to learn is that the deescalation isn’t strictly human behavior, It is, in fact, something we are now seeing in pigs. Back in 1964, there was a concept created known as “the bystander effect.” This term explains how some people in a large crowd feel discouraged from interfering in some kind of emergency situation. Like if a crime is happening, or somebody’s being bullied. If there’s more people around it’s actually less likely for somebody to intervene. However, the opposite is true if there are less people watching. So, in a standoff between two people and one witness, that one witness is more likely to intervene. And it turns out, it’s exactly the same for pigs.
NATE: And we don’t know if that changes if the pigs are wearing clothing.
CALLI: You know, I don’t think that part’s been checked yet.
NATE: Alright so, the part they have been studying, pigs intervening. I feel like I ask this question a lot but, how did they figure this out?
CALLI: As always, it was a group of researchers who figured this out. These researchers were from the University of Torino in Italy and they were watching a group of 104 pigs on a farm in 2018. They saw and recorded interactions like aggressive behaviors like the pushing, biting, head-knocking, and things like that. But what they found was that after a fight, both the victim and the aggressor showed “reconciliation behaviors” afterward, like nose-to-nose contact, or resting their heads on one another, they actually sort of bonded after the trauma.
NATE: And the researchers felt these behaviors were a result of a bystander pig getting involved in the fight?
CALLI: That’s where the study gets interesting. Seem behavioral differences in the pigs, depending on which pig was approached by the bystander is sort of what changed it all. If the bystander approached the aggressor, their aggressive behaviors were reduced, the pig was basically talked down it almost seems like. But if they engaged with the victim, there was no difference whatsoever… at first. Because what DID change was that over the following hour or so, the victim pig’s anxiety behaviors decreased. Those would be signs like things like yawning, scratching, shaking, or chewing with an empty mouth. These things significantly dropped whenever a bystander pig got involved. So say you’ve got two friends fighting, one steps in the middle, if they go to the person who’s being the bully, they can talk them down, whereas if they go to the victim, they’re basically helping reduce their anxiety and make them feel better. And yeah, this is all because of the bystander pig.
NATE: That’s pretty crazy. That’s more emotionally complex than I would have thought would happen with pigs. But I gotta ask, did this happen every time? Is this consistent in pig fights?
CALLI: Okay so, it’s not every time, but there were a few consistent variables. In fact, if the bystander pig was closely related to either participant in some way, whether they’re family or friend, the fight would almost always be broken up.
NATE: So you’re saying that the bystander effect was in action for most of these battles - but they were especially strengthened by a previous social connection?
CALLI: Exactly. This experiment shows us that pigs might value different relationships and have their own sort of social hierarchy. The feuding pig siblings usually went back to normal after a fight. But distantly related, or non-related, pigs were more likely to engage in apologetic behavior. It was really interesting to see, like, they would do the resting the head on the shoulder routine or giving the other pig some food. It was a sign of apology and it was more likely, like they were saying, to be seen in pigs that were less likely to be related, whereas ones that were more closely related with that sibling dynamic, they more or less just went back to normal.
NATE: So this is one end of the bystander effect that you were talking about, how if there’s few people, there’s actually a higher likelihood of intervention. Does the other end of the bystander effect also come into play with the pigs? Like, if there’s a lot of them, are they less likely to intervene?
CALLI: Yes! And that’s kind of what’s interesting. That’s actually the main reason why the bystander effect has never been seen in pigs. We normally tend to keep pigs in very close proximity to one another as a group, which is known as a ”drift of pigs,” which I love. Makes me think of like a snowdrift of pigs which is terrifying. But anyways, if you were to see three pigs break up a fight, it might have felt more like a fluke than a natural occurrence in those larger groups. But, when they separate them out into these smaller groups and actually study them a little bit more, that’s when they were able to see it. So, yes, the bystander effect works on pigs exactly the way it works on humans.
NATE: So what you’re telling me is: I need to watch pigs more intently if I want to witness something life-changing.
CALLI: I mean I think the life-changing thing for me is that I might reduce how much bacon I eat in the future.
[SFX: WHOOSH]
NATE: Let’s recap what we learned today to wrap up.
CALLI: Those feelings when emotions start to take a toll on you physically aren’t just in your head: turns out, there’s a science related to the physicality of emotions known as body mapping that can help you figure out which emotions affect different body parts. Although it’s not a replacement for good old fashioned therapy, it IS a wonderful tool to keep yourself centered!
NATE: A simple dive into the brain of the amphibian axolotl has revealed an evolutionary link with mammals that allows the axolotl to regenerate injured body parts - including its own brain. Scientists are hoping to soon unlock this ability to help treat serious injuries in humans, and maybe - give us our own abilities to regenerate!
CALLI: When two people start fighting in front of a third person, science shows us that the third person will almost always intervene in some way in a phenomenon known as the bystander effect - but recently, it was discovered that this phenomenon affects PIGS, too. In a breakthrough discovery, it was found that pigs have a complex social hierarchy that allows them to intervene in fights when necessary. This means that pigs are capable of social standings just as complex as, and possibly even more so than humans!