Your Brain Invents Pain. Here's Why.

Summary

The Rest Is Science: "Your Brain Invents Pain. Here's Why."

Podcast Hosts: Professor Hannah Fry & Michael Stevens (Vsauce)
Release Date: July 5, 2026

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Episode Theme Overview

In this episode, Hannah Fry and Michael Stevens explore the surprisingly subjective and constructed nature of pain. Rather than being a direct readout of bodily damage, pain is revealed as a verdict made by the brain, often serving as much as a protective illusion as a reflection of reality. Through experiments, fascinating anecdotes, and emerging science, they probe what pain really is, why some people don't feel it at all, and how understanding pain's mechanisms may hold the key to solving chronic suffering.

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Key Discussion Points & Insights

Personal Pain Experiences and Thresholds

• Opening Stories (00:04–01:47)
  • Michael recounts scratching his cornea while mowing: “They immediately put this special pain relieving eye drop in, but that was bad.”
  • Hannah introduces “suicide headaches” (cluster headaches), noting their excruciating intensity surpasses even childbirth.

The Cold Pressor Test: Measuring Pain for Science

• Live Pain Challenge Segment (04:38–12:52)

  • Both hosts perform the ice bowl hand dunk—a scientific means to measure pain tolerance.

  • Redheads have a different (often higher) pain tolerance and require different anesthesia, anecdotally referenced.

  • Experiments show swearing or feeling stressed changes pain endurance—mindset and context matter.

    “Can they hold in their hand for longer when they're swearing, for example? The answer, by the way, is yes.” – Hannah Fry (07:11)

  • The “thermal grill illusion” (Frankfurter Experiment) discussed: alternating hot and cold triggers a burning pain not present in either alone.

    “What that demonstrates is that pain is not this faithful readout of damage. It's a verdict that your brain is constructing and actually sometimes just plain wrong.” – Hannah Fry (12:52)

Etymology and Redefinition of Pain

• Language and Definitions (13:32–15:30)
  • "Pain" comes from Latin poena ("punishment"); many pain-adjacent words suggest burden or curse.
  • New medical definitions highlight pain as an experience “associated with or resembling that which is associated with actual or potential tissue damage.”

Pain Pathways: How the Brain Constructs Pain

• Nociception vs. Pain (15:57–18:00)

  • Nociception is the nervous system’s detection/encoding of possible harm—distinct from the subjective experience of pain.
  • Fast "jab" pain (A-delta fibers) vs. slow aching pain (C-fibers): two propagation speeds and functions.

    “That initial, urgent, fast pain is like move. ... But then the slower throbbing pain that lasts longer is there to keep reminding you to tenderly treat the injured part of your body.” – Michael Stevens (18:00)

• No Pain Receptors in the Brain (18:26–19:19)

  • Pain is constructed elsewhere; even severe headaches come from structures around, not within, the brain itself.

Modulating Pain: Mind, Memory, and Mood

• Harnessing the Brain for Free Analgesia (35:52–41:50)

  • Stress, experience, belief, and even social cues dramatically shape pain.
  • Studies (Irene Tracy, "Queen of Pain") use MRIs and controlled pain stimulations to show that mindset alters physical experience.
  • Children may exaggerate pain due to novelty and powerlessness, but parental reaction can reduce their suffering.

    “If you are like happy and clappy and it’s like, hey, no big deal, let’s crack on... It’s not just that they ignore the pain. It’s that the actual pain that they feel is lower.” – Hannah Fry (39:35)

• Subjective Measurement Limitations (40:18–41:50)

  • Efforts to create an objective “pain scale” (e.g., the dolimeter) faltered because pain is fundamentally constructed and subjective.
  • Memory of pain is stored as “peak” and “end” moments, not as a continuous sum—aligning with Kahneman’s research on experience vs. memory.

When Pain Disappears: Genetic and Clinical Extremes

• People Who Don’t Feel Pain (26:35–32:12)
  • Mutation in SCN9A gene (affecting NAV1.7 sodium channel) can eliminate pain sensation—people with this condition risk severe injury and death, especially in childhood.

    “It is the most horrific curse. ... When he was teething... he had bitten off a chunk of his own tongue and not even realized.” – Hannah Fry (30:10)

  • Leprosy, misunderstood as “rotting flesh,” is nerve death leading to loss of pain and self-inflicted injuries.

The NAV 1.7 Channel: Future of Pain Control

• Pharmaceutical Innovations and Risks (45:54–49:33)

  • Discussion of the NAV 1.7 sodium gate—a promising target for selective pain relief.

  • Bullet ant stings cause extreme pain by jamming this gate wide open; mutations or drugs that block it could bring relief.

    “So the question is, can you do something that directly targets that NAV 1.7? ... Unfortunately, NAV 1.7 is also really close in design ... to NAV 1.5, which is absolutely critical to maintaining a heartbeat.” – Hannah Fry (48:15)

  • The delicate challenge is targeting pain nerves without affecting essential functions like heart rhythm.

Science, Social Context, and the Placebo Effect

• Social and Psychological Aspects (43:07–45:17)

  • The effectiveness of pain relievers like Tylenol (paracetamol) appears to increase with societal trust—a proof of the brain’s role in amplifying or muting pain.
  • “The nurses made me better”: Professional empathy unlocks real, neurological pain relief.

  “Physics keeps me safe on an airplane. But the flight attendants make me feel safe.” – Michael Stevens (45:26)

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Notable Quotes & Memorable Moments

On Pain’s Subjectivity:

• “Pain is not this faithful readout of damage. It's a verdict that your brain is constructing and actually sometimes just plain wrong.” – Hannah Fry (12:52)
• “Nowadays it looks more like it’s a verdict our brain comes to. I think that’s a great word to use, verdict. It looks at the evidence and it just kind of has to come up with a decision, and it might be wrong even.” – Michael Stevens (14:03)

On the Protective Role of Pain:

• “Not having any pain at all is like such a horrific curse. … If you want real proof, leprosy … is actually just a bacteria that kills the nerves. So means that you cannot feel pain and thus it's your own actions that mean that you lose toes, you lose fingers. These are self inflicted wounds that are unfelt, essentially.” – Hannah Fry (31:10)

On Mindset Shaping Experience:

• “The point that you just made about how you're feeling being such an integral key part of it. It is, as it turns out, almost all of the story is what's going on in your head.” – Hannah Fry (35:52)

On Nursing & Comfort:

• “I always think that actually the doctors might have cured me, but the nurses made me better.” – Hannah Fry (44:46)

On Future Hope:

• “There will come a point in the future where we can create something that allows you on demand to take some kind of pharmaceutical that just switches off that NAV 1.7 when you need it and not when you don't.” – Hannah Fry (49:33)

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Important Timestamps

• Personal pain stories: 00:04–01:47
• Cold pressor experiment: 04:38–12:52
• Thermal grill illusion explained: 07:11–12:52
• Etymology of pain: 13:32–15:30
• Nociception & pain transmission: 15:57–18:00
• Brain and pain construction: 18:26–19:19
• Genetic painlessness: 26:35–32:12
• Pain measurement limitations: 40:18–41:50
• Placebo effect discussion: 43:07–45:17
• NAV 1.7 channel & future drugs: 45:54–49:33

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Episode Summary

What we think of as “pain” is not a pass-through of tissue damage, but rather a complex, brain-made verdict, assembled from sensory signals, expectations, beliefs, prior experiences, and social context. Neither reliable nor always accurate, this verdict is protective in intent but often misfires—sometimes silencing pain when needed (wartime, emergencies), sometimes blaring it with no physical cause, and in rare genetic cases, failing to trigger at all.

The hosts deftly blend personal stories, live experiments, and current research, showing that pain’s reality is as much psychological and social as it is biological. They highlight the exciting (and daunting) search for highly selective pain treatments, particularly locking (or unlocking) the NAV 1.7 sodium channel—an innovation potentially more game-changing (and safer) than current opioid-based approaches.

The upshot: pain isn’t punishment—though the word suggests it—but a “gift with caveats,” reminding us of our biology’s creative, sometimes fallible attempts to keep us safe.

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For fans of science, skepticism, or the strange machinery of the mind, this episode is as enlightening as it is full of moments of wit, empathy, and good-humored curiosity.

Transcript

[Hannah Fry]

Welcome to the Rest Is Science. I'm Hannah Fry.

[Michael Stevens]

And I'm Michael Stevens.

[Hannah Fry]

Okay, Michael, what's the worst pain you've ever been in?

[Michael Stevens]

Oh, goodness. I think it was when I was mowing a yard and a piece of sand scratched my cornea.

[Hannah Fry]

Oh, yeah.

[Michael Stevens]

I mean, it was bearable. It wasn't like childbirth, you know, I'm not saying that. I'm just saying that I thought it would get better and it didn't all evening, so I had to go to the hospital. And they like immediately put this special pain relieving eye drop in, but that was bad.

[Hannah Fry]

So as soon as you had the pain relief, it was kind of okay, Totally fine.

[Michael Stevens]

It was so weird. In fact, the doctor wouldn't give me more to take home because he was like, people use this and then they can't even tell that their eyes are damaged. And so it's like dangerous.

[Hannah Fry]

Right. People do talk about childbirth being one of the most painful things you can experience, but it's not the most painful.

[Michael Stevens]

What is the most painful?

[Hannah Fry]

Well, there is a condition which actually my ex husband had, which are known as suicide headaches.

[Michael Stevens]

Oh, like the ice pick headaches. I have heard that people who have given birth and had these kinds of headaches say the headaches are worse.

[Hannah Fry]

Absolutely.

[Michael Stevens]

He had them.

[Hannah Fry]

He had them. Yeah. And when he would have them, I mean, you really knew that he was in absolute agony. Essentially the reason why they are called, I mean, it's an awful, awful phrase. But historically, these things are so, so catastrophically painful. It feels like a buildup of pressure in your head. But I think in particular, it's the nerve in your face, the trigeminal nerve that is really irritated. That's an understatement. Is really under extreme pressure and pain when all of this is happening. And historically, because there was no real access to pain relief, people would be in such excruciating pain that they would try and take their own lives just to escape it.

[Michael Stevens]

Wow. Yeah.

[Hannah Fry]

I mean, thankfully, that puts childbirth in perspective really, doesn't it? It is a bit annoying when you then go on to have children with people who suffer from suicide headaches because they had no sympathy. No sympathy whatsoever. Okay, today, Michael, we're going to be talking about pain. I'm going to see your level of pain that you. That you can tolerate.

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[Hannah Fry]

We're going to talk about people who feel nothing and what that does to them. And we are going to talk about the underlying question under all of it. Can we make the pain go away?

[Michael Stevens]

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[Hannah Fry]

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[Michael Stevens]

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[Hannah Fry]

Now, understanding how Greenland sharks, cellular repair and immune systems seem to have managed to keep them cancer free for centuries, that could open up exciting research pathways

[Michael Stevens]

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[Hannah Fry]

So by exploring the unexpected, Cancer Research UK scientists are uncovering new ways to tackle over 200 types of cancer. Their work has helped to double survival in the UK over the last 50 and continues to save and improve lives around the world.

[Michael Stevens]

For more information about Cancer Research uk, their research and breakthroughs and how you can support them, visit cancerresearchuk.org TheReestisScience

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[Hannah Fry]

Okay, Michael, I have asked you to prepare something here.

[Michael Stevens]

You've asked me to prepare. I've got a bowl of water here and I'm going to put ice in it. Yeah, I've got the world's tiniest ice tray.

[Hannah Fry]

I'll be all right.

[Michael Stevens]

Should be okay. I'll crack these in. Oh yeah.

[Hannah Fry]

Okay, so what we're going to do in a moment is we are going to plunge our hands into these ice bowls. I also have one here, by the way, pre prepared. It's an opaque bowl, but you can just about see in the bottom. Those of you who are watching, there's I would say substantially more ice than in Michael's.

[Michael Stevens]

Okay, yeah I'm afraid I don't have enough ice. This is all I have.

[Hannah Fry]

It'll be fine.

[Michael Stevens]

It'll be fine.

[Hannah Fry]

You'll just look like absolute nails, Michael.

[Michael Stevens]

I'm going to look so strong. I mean, we. It cool down the water a bit. This was already very cold water.

[Hannah Fry]

This is actually a standard way that researchers can measure pain thresholds in people. Some people are much more able to sustain holding their hand in the sort of the extreme burning sensation that you get when your hand is in real cold. Incidentally, actually, redheads. The research is developing here that redheads feel pain in a different way to. To other non mutants like yourself.

[Michael Stevens]

Now, I've heard that. I've heard that they don't feel pain. They have to be anesthetized differently. But you're saying they feel it in a different way or just a different magnitude?

[Hannah Fry]

Different magnitude. I think that they have a slightly higher tolerance to pain.

[Michael Stevens]

Interesting.

[Hannah Fry]

But takes more to knock them out. So we're gonna see. We're gonna both plunge our hands into this while I tell you about the other experiments that they do to cause people pain. And we're gonna test Michael. We're gonna see who can hold it in longer, you or me, before the pain gets too extreme.

[Michael Stevens]

Okay.

[Hannah Fry]

All right, you ready?

[Michael Stevens]

I'm ready.

[Hannah Fry]

Okay, let's do this. Let's do this.

[Michael Stevens]

Count me down. Oh, you're in.

[Hannah Fry]

I'm in. I'm in. Three, two, one, go. Okay, you've gone for a flat hand. I've gone for. I'm maybe trying to cheat slightly by tucking my thumb in into a fist, but we'll see. It's already, I'll be honest, quite cold.

[Michael Stevens]

Yeah, mine's cold. I should have more ice.

[Hannah Fry]

It's okay.

[Michael Stevens]

It's okay. This isn't scientific. This is just a little challenge. It is uncomfortable.

[Hannah Fry]

It is already uncomfortable for me too. I want to tell you, though, while our hands are in here, you can hold it in for about three minutes or so before it really becomes absolutely unbearable. Also, be careful about doing this at home because you can genuinely give yourself. Give yourself ice burns. But the way that people use this in research around pain is that you establish an individual person's baseline, and then what you can do is you can adapt it so you can see. Can they hold in their hand for longer when they're swearing, for example? The answer, by the way, is yes.

[Michael Stevens]

Yeah.

[Hannah Fry]

Do they want to take their hand out earlier when they are feeling particularly stressed, for example? The answer is yes. But researchers, for a really long time have tried to come up with different ways to ethically subject people to pain. This is one of the kind of older, more traditional methods. But there is this new one that people are using, which I think is really interesting. It's something that was sort of discovered as a way to research pain by a guy called Frederick Lindsey Stead. And what he was doing, he was at home. He wondered what would happen if he got a pack of frankfurters out of the fridge and took half the pack of frankfurters and microwaved them, and then left the others at sort of, you know, quite cold temperature, sort of 5 degrees centigrade. And then he arranged them on a plate where it would be 1 at 40 degrees, 1 at 5 degrees, 1 at 40, 1 at 5, 1 at 41, a 5 sort of interchange them, and then later a flat palm across all of the frankfurters. Now, I noticed you said when I mentioned this. Have you come across this before?

[Michael Stevens]

Yeah, the thermal grill illusion. We did it with hot dogs on an episode of Minefield.

[Hannah Fry]

Oh, did you?

[Michael Stevens]

Okay. Yeah, it's painful. And why don't you tell us why? How are you feeling right now, by the way, in the ice?

[Hannah Fry]

I would say I'm enjoying the distraction of talking about hot dogs.

[Michael Stevens]

Okay, we'll keep going.

[Hannah Fry]

How are you? Is it hurting yet?

[Michael Stevens]

It does hurt, but it's not bad enough. It's getting worse. I mean, my ice is almost all melted already. I've made it very easy for myself by just not being an iceman.

[Hannah Fry]

You're gonna look like an absolute superhero, I would say. I think the tucked thumb has definitely helped me here.

[Michael Stevens]

Oh, yeah.

[Hannah Fry]

The outside of my hand is like. Is really. If I. Especially if I concentrate on it, it's really, really burning a lot. And this is the thing. This is part of the reason why the Frankfurt thing ends up hurting. Because actually, really intense cold water, it doesn't register in your body as, like, very cold. It registers almost as burning. It sort of feels the same sensation as burning. And the reason is because it activates this pain pathway that your brain reads as a burning sensation. So your skin is effectively got two different receptors that are running up to the brain. One of them is like a cool reporter. And this one says, okay, it's fine. There's nothing to worry about. It's not unbelievably cold. It's cool, so you don't need to worry about it. And then the other one is a burning alarm, right? That's like, ouch. Get this away. Suddenly, my hand actually hurts way more when I'M saying than burning. But cold can also trip this, right? So extreme hot or extreme cold will trip this sort of burning alarm. So what happens with this illusion is that the warm hot dogs, the warm frankfurters, tell your brain, hey, look, this is definitely not cool because it's warm, right? It's not like if you just held the 5 degree frankfurter, your brain would not trigger the burning alarm because it would say it's cool. So it's fine. It's no big deal. It's not super freez because the warm ones are there. They stop that trigger from happening. So your brain doesn't get the message that this is an okay temperature. And so only the burning sensation appears in your brain. If I explain that, I mean, you give it a go, maybe you'll be able to explain it better.

[Michael Stevens]

Me, I haven't looked into this recently. I've heard that it's like you've got hot and cold receptors. And obviously they don't go off together ever unless there is excruciating urgent pain. And so if you can line the cold and warm hot dogs up close together in a line and put your hand or your arm on them, your brain's getting a signal from both cold and warm receptors. And that only happens when you're like literally having your arm cut off.

[Hannah Fry]

Yeah.

[Michael Stevens]

It hurts so badly.

[Hannah Fry]

And does it? Cause I've never done it. Does it really hurt?

[Michael Stevens]

I actually did not do it. Oh, and I regret this. We did it on Rosanna Pansino. We had her come on and she, like, couldn't keep her hand on it. I don't know why, why I didn't try it. I think it's because I was the host and we were filming. But they have an apparatus at the Exploratorium in San Francisco that uses metal rods that are thinner and it's more effective. And I've always wanted to try that one. I also want to build one and put it in the curiosity box so you can, like, hurt. Are you giving up?

[Hannah Fry]

Yeah. Do you know, it's so strange because it's noticeable that when you are talking about excruciating pain, it hurts so much more than when you're talking about, I don't know, like, going to visit an

[Michael Stevens]

exploratory and a fireplace. Does that help you?

[Hannah Fry]

It does, it does.

[Michael Stevens]

It's like needing some, like, math to do some. Some just like algebra equations.

[Hannah Fry]

I'm warm blooded for maths. Yes. I'm absolutely fine with that. Do you know what?

[Michael Stevens]

I think I'm giving up.

[Hannah Fry]

It's moving up my arm. Now the cold is moving up my arm. I think I'm giving up. I don't know how long I lasted. About three minutes, I reckon.

[Michael Stevens]

Probably more than three minutes. It's at least. At least seven minutes.

[Hannah Fry]

Oh, I can't feel my hand.

[Michael Stevens]

More like maybe six minutes. That's good. I feel like this wasn't a fair test. My ice, it's all melted by now. I have no ice left, so I've melted all that ice.

[Hannah Fry]

You're just having a tepid bath.

[Michael Stevens]

It's not tepid, but I think that at this point it's like a maybe a one or a two out of ten pain wise.

[Sponsor/Ad Voice 2]

Right.

[Michael Stevens]

Actually, I'm more uncomfortable from holding my hand in this position. So I didn't do a good demonstration and I lost. I lost my dozen ice cubes. So warm drinks for me today. I mean, I can keep my hand in just to prove myself, but there's no ice left left. It's only going to warm.

[Hannah Fry]

I think you can do the rest of this episode with dry hands.

[Michael Stevens]

Okay, it's coming out. When we're in person, we'll have thermometers. We'll do this with lots of ice, same temperature, and we'll really see who can take more pain.

[Hannah Fry]

We'll see if the ginger really is talking a big game. I think if it felt more competitive as well, I think that that would sort of overtake. I would want to stay in even longer. Here's the thing though, okay? So the reason why that sausage experiment is so interesting is that actually you're not in pain. You're not in dange. You're not hurting. You are perfectly safe. You could hold a 40 degree hot dog and be fine. You can hold a 5 degree hot dog and be fine. What that demonstrates is that pain is not this faithful readout of damage. It's a verdict that your brain is constructing and actually sometimes just plain wrong. Do you know where the word pain comes from, by the way?

[Michael Stevens]

No, I don't.

[Hannah Fry]

It goes back to Latin, unsurprisingly, poena, which is penalty or punishment. Also in the Greek poini, which is blood money. And it's sort of like the price that you pay for spilled blood, right? But underneath all of it, it's like the root of the word pain is to pay to kind of atone. It's like pain is sort of a debt that you are paying.

[Michael Stevens]

Interesting. You know, my mother's maiden name was Pain.

[Hannah Fry]

Oh, really?

[Michael Stevens]

Now you guys can all steal my bank monies. Wait, spel spelled P A Y N E. Like Thomas Paine. Common sense. Anyway, so pain is a punishment, but nowadays it looks more like it's a. A verdict our brain comes to. I think that's a great word to use, verdict. It looks at the evidence and it just kind of has to come up with a decision, and it might be wrong even.

[Hannah Fry]

In other words, that are to do with pain, like excruciating. Excruciating has the word sort of crux, as in the cross. Right. Like the crucifix hidden inside it.

[Sponsor/Ad Voice 4]

Right.

[Michael Stevens]

Oh, wow. Yeah.

[Hannah Fry]

And I think that, like, people have always filed pain under this. This idea of it being a curse or a sentence. And now because, as you say, actually we know that it's a verdict because we know that it's not sort of a direct reading of your environment. In 2020, the official definition of pain changed. Pain is now defined as associated with or resembling that which is associated with actual or potential tissue damage. And this is an important distinction because there are some people who actually have really serious chronic pain in their bodies without there being the tissue damage or the underlying physical cause that can be treated to cut the pain off.

[Michael Stevens]

Yeah. My hand is still very cold. Yours must be so cold still. Like, I was sitting on it, and now I've got it in my leg pit the other side of my knee. I don't know. What is that called instead of an armpit? Yeah, the crook of your arm. The crook of my leg. I'm like, squeezing it. See, look how hairy my legs are. That gives you a sense of how warm I am all the time.

[Hannah Fry]

Insulation all over the place.

[Sponsor/Ad Voice 2]

Right.

[Hannah Fry]

Should I give you some quick pain facts?

[Michael Stevens]

Yeah, please do.

[Hannah Fry]

So nociception is essentially your perception of pain.

[Michael Stevens]

That's a great word, by the way. Nociception.

[Hannah Fry]

Isn't it good?

[Michael Stevens]

Is there any susception? Nociception?

[Hannah Fry]

There is none. None at all. So nociception, that's your sensory nervous system, is the process of actually detecting and encoding pain stimuli. And it's not the same thing as pain. Nociception is like the raw signal that is kind of traveling up the nerves. And the pain is what your brain decides to do with it.

[Sponsor/Ad Voice 1]

Ah.

[Michael Stevens]

It's the equality of it.

[Hannah Fry]

All right, totally. Because you can have the signal with no pain.

[Sponsor/Ad Voice 3]

Right.

[Hannah Fry]

Under anesthesia, your body is like, cut wide open. These signals are definitely firing towards your brain, but you're not registering it. And you can have the reverse. You can have pain with no signal. So people who have had limbs amputated, for instance, can end up feeling phantom pain for limbs that are no longer there.

[Michael Stevens]

Right, right, true.

[Hannah Fry]

So the two things are not. It's not like a one to one thing. But in terms of that signal, that nervous system signal that travels through your body, I'm sure that you will have noticed this just by, like, stubbing your toe. There are two different pain signals. If you hit your thumb with a hammer, dink, for example, then you get like a very precise jab. It's like, ouch. Very quickly. Like, pull your hand away, sort of. If you put your hand on a hot hob, for instance, as well. That's the other one incredibly quick signal that is going through these fibers that travel to your brain at 20 meters per second. But the dull pain that you get after you pulled your hand away from being hit by a hammer or like, if you stub your toe, for instance, these are your C fibers, and they move at 1 meter per second. So actually, I always think about when I stub my toe, I really noticed this. Stub my toe. And then I sort of. In my head, I'm like, one, two, there it is. And that's literally the pain signal physically traveling up your body and into your brain.

[Michael Stevens]

Yeah. It has a different speed. I made a little. A little YouTube short about the speed of pain or. Both of these kinds of pain have their own purposes. That initial, urgent, fast pain is like move. It makes you move away or stop. But then the slower throbbing pain that lasts longer is there to keep reminding you to tenderly treat the injured part of your body.

[Sponsor/Ad Voice 5]

Yeah.

[Hannah Fry]

Don't ignore it. I tell you where you don't get those pain receptors, which is in your brain, where the actual pain is constructed overall.

[Michael Stevens]

Oh, funny. Yeah.

[Hannah Fry]

Even when you have a headache, it's not your brain that's hurting at all. It's sort of the surrounding of your brain. I mean, you see this with brain surgery.

[Sponsor/Ad Voice 6]

Yeah.

[Michael Stevens]

Right. So if someone said, I'm gonna torture you by stabbing right where you feel pain, you wouldn't feel it.

[Hannah Fry]

You wouldn't feel it because there's no pain receptors in your brain.

[Michael Stevens]

That is a weird thing, by the way, that I want to look into more. So first of all, we've all seen, like, I don't know if we all have, but open brain surgery is so weird because the person doesn't have to be under anesthesia. There's like local anesthesia for where their skull has been cut in the flesh. But then you can just poke around, slice around. Ask them, like, okay, so can you still feel your fingers? And they're like. Yep. And they're like, okay. I guess you don't need that part of your brain. I don't think that's exactly how it goes.

[Hannah Fry]

Century by vessels.

[Michael Stevens]

What I. That's how I would do it. I would use an obsidian knife, though, by the way.

[Hannah Fry]

Yeah.

[Sponsor/Ad Voice 2]

Thank you.

[Michael Stevens]

That's a call out to a previous episode or an episode to come, depending on the editor's schedules. But I've always wondered about the feeling of mental exhaustion and what causes that. It's not pain, but it is a feeling we have where if you have been very focused for a long time, if you've been thinking a lot, you feel like you've used your head. Is that because you've actually been using your eyes a lot? What is that feeling? It's not pain, but our brains don't have nerves in them that give us feedback on, like, how it's doing. Is it hurting? So what's up with mental exhaustion as a feeling?

[Hannah Fry]

So I don't know the answer to that for sure. Right. And maybe there's going to be people in the comments who know way more about this than I do, but one thing I will say. Have you ever come across the electrical current stimulators that you wear on your head?

[Michael Stevens]

The EEG nets?

[Sponsor/Ad Voice 6]

No.

[Hannah Fry]

No, this is.

[Michael Stevens]

Oh, it's a stimulator.

[Hannah Fry]

Yeah. Not a detector. Okay, so here's this idea, right? Is that actually what's going on in your head when you're thinking and actually when you're feeling pain? I mean, pretty much everything that you sort of sense in your body, what's happening is that charged particles are moving around.

[Michael Stevens]

Sure, yeah.

[Hannah Fry]

One of the theories, I guess, is that exhaustion but also things like depression are really amplified by there just not being enough charged particles in the right place.

[Sponsor/Ad Voice 5]

Huh?

[Michael Stevens]

Yeah.

[Hannah Fry]

So anyway, I have this thing, I have this headset that I wear sometimes. It sounds crazy, but it's actually. It's FDA approved. It's like used by the nhs, and it just applies this very small electrical current on your head and then suddenly your brain fog just goes away. Like suddenly you actually.

[Michael Stevens]

Well, you gotta show it to me. Where is it? Go get it.

[Hannah Fry]

Am I gonna get it?

[Sponsor/Ad Voice 1]

Yeah.

[Michael Stevens]

A few moments later, it's like this little headset. Ah. Okay.

[Hannah Fry]

The thing is, this is a medical device, right? You sort of have to do it under supervision of a doctor. So how did you get it from a doctor?

[Sponsor/Ad Voice 5]

Right.

[Michael Stevens]

Okay. So you said, hey, my charged particles just aren't flowing.

[Hannah Fry]

My Charged particles aren't flowing. Hit me up. And this has a bit of a reputation, these kind of things, because, you know, in the 1950s, 60s, 70s, electric shock therapy was really dramatic and, and I think quite unethical in a lot of the ways that they use this. But we're talking like really gentle and it's just about sort of. So you get a little. There's a slight difference in current from one end to the other end. You've got an anode and a cathode.

[Michael Stevens]

So how does it affect inside your skull? Is it like the electric field, like almost a magnet or.

[Hannah Fry]

I mean, essentially everything that's going on in your neurons is about charged particles moving from one place to another.

[Michael Stevens]

Right, yeah. Squirting around different concentrations of sodium ions.

[Hannah Fry]

Exactly. So what this thing does is it changes the resting membrane potential of the neurons.

[Michael Stevens]

Aha. So could it be dangerous if misused?

[Hannah Fry]

I mean, probably. I think like, I think there's very good evidence about this thing. It's also, by the way, an incredibly low electrical current. Like you couldn't even feel it really if you put your fingers on it. But the idea is that you just give your brain a bit of a head start and then over time you sort of build new pathways.

[Michael Stevens]

Okay, so you've had good results from it.

[Hannah Fry]

Yeah, I really like it. I really like it.

[Michael Stevens]

How often do you use it?

[Hannah Fry]

Five times a week.

[Sponsor/Ad Voice 5]

Oh, wow.

[Michael Stevens]

So every. Every day except on the weekends where you just let your brain chill out.

[Hannah Fry]

Chill out and deionize.

[Michael Stevens]

Deionize. What is it called?

[Hannah Fry]

Transcranial direct current stimulation.

[Michael Stevens]

Oh, interesting. I've done transcranial magnetic stimulation on Minefield.

[Hannah Fry]

Oh yeah.

[Michael Stevens]

In a lab where they try to change how your neurons are working, specifically in Broca's area, just to demonstrate that they can stop you from being able to speak. And this also has a lot of therapeutic uses. So it sounds like what you have is a like at home version.

[Hannah Fry]

Yeah.

[Michael Stevens]

Of that technology.

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[Hannah Fry]

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[Hannah Fry]

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[Michael Stevens]

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[Hannah Fry]

Of course, Jason. It's in the name. Sam's Club.

[Michael Stevens]

Oh, yeah.

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[Hannah Fry]

Here's the thing, though, all thinking and feeling that's going on in your body is essentially these charged ions passing through different channels. I mean, that's. They're sort of squirting around your body, right? That's essentially what's happening. The way that pain works. We know this now. The way that you feel pain is that at the tip of every pain nerve is this little tiny gate that the ions sort of get squirted through this, like, little sodium tunnel. And it's called NAV 1.7. It might be that people call it NAV, but I'm going to call it NAV 1.7. So if that gate is open, then the little ions get squirted through and get up to your brain and you're like, oh, I feel pain. Ouch. But if that gate is blocked or sort of modified in some way that stops the ions being allowed to pass through, then you would feel no pain. You would still have sensation. You would still be able to, like, feel and touch things, but you would have no pain whatsoever. And it turns out that there is a gene. It's called SCN9A. There is a mutation in that gene that mucks up this particular little gate and means that there are some people who can feel no pain whatsoever.

[Michael Stevens]

Wow. I've read fictional accounts of people with such a condition. In the Flowers in the Attic series

[Hannah Fry]

when I was a kid, right.

[Michael Stevens]

There's a child in, like, the second books and on who doesn't feel pain. And so they always have to be so careful because this kid won't know if they've scratched themselves. They can get an infection. They won't know if they've broken a bone.

[Hannah Fry]

I've met someone with this condition.

[Sponsor/Ad Voice 1]

Really?

[Hannah Fry]

Yeah. He's called Stephen Peet. He is so amazing. American guy, has worked with researchers who are trying to, like, isolate this particular pathway, try and work out if there's different pain medications. He was so amazing. But I have to confess to you, it's the only time I've ever interviewed someone where I had to pause the interview midway through to go and be sick. I had to vomit because it was so horrific. The stuff that he was telling me. I couldn't handle it. And I basically threw up in the middle of the interview.

[Michael Stevens]

Oh, wow. The only time I've ever actually felt really sick and I had to excuse myself was when I was at Berkeley looking at actual human brains. And I pretended like it was the formaldehyde smell that made me sick. And I'm like, I gotta go. I got too big of a whiff. But really, it was the idea that I was holding someone's identity. Like, everything they'd felt, every memory, every time they'd taken a child to the playground, it all happened in this organ that we don't understand. And I was holding it. We were just looking at it, and I'm like, oh, my gosh. This is too, too close to a human. So there's my admission that it wasn't the formaldehyde.

[Hannah Fry]

Yeah. Wow. Right? It's incredibly profound.

[Michael Stevens]

Okay, so his name is Steven Pete.

[Hannah Fry]

Stephen Pete. Yeah.

[Michael Stevens]

Talk about a mondegreen. That also sounds like it's two people. Steve and Pete.

[Hannah Fry]

It's two Stephen Pete.

[Michael Stevens]

People do that to me. Michael Stevens. And they're like, so is your name Steven or Michael? And I'm like, you can see there it says Stevens. No one's first name is Stevens. If my name was Michael Steven, then maybe I'd get it. But this happens to me every time. Not every time, but a lot.

[Hannah Fry]

I think you're a better Michael than a Steve.

[Michael Stevens]

If I had a son, I told my wife I really wanted Steve Stevens. I did meet a guy whose name was Stephen Michaels. He's a brilliant musical performer, performed at my daughter's preschool years ago. And I'm like, dude, Stephen Michaels, I gotta tell you, my name is Michael Stevens. And he was like, oh, that's neat.

[Sponsor/Ad Voice 1]

Later.

[Michael Stevens]

And I was like, no, but wait. We're. We're destined.

[Hannah Fry]

We're destined to be together. Oh, that's good. I like that. I have two friends, a gay couple who are both called Emma, which I really enjoy, and they've got a little daughter. To the daughter, it's like, oh, what's your mummy called? Oh, my mummy's called Emma. And my mummy's called Emma. I just really like that a lot.

[Michael Stevens]

Oh, wow. Yes.

[Hannah Fry]

I think Michael Stevens and Steven Michaels, you could have been the most beautiful gay romance story. That would have been so lovely.

[Michael Stevens]

What would we have called our kid? Because there's only those two permutations of two things. Yeah, we'll figure that out later.

[Hannah Fry]

Anyway, okay, I'm going to tell you some of the stuff that Steven Pete told me. Okay. But I'm. I'm editing this very heavily, obviously, because I don't want you to throw up during this.

[Michael Stevens]

First, I want to say cycle mevens. That could work. Or ven me. Maybe that one. If we wind up having a second,

[Hannah Fry]

I think you should have Steven Stevens and Michael Michaels.

[Michael Stevens]

That would be good, especially if they were twins. But how do you change the last name of your own child? Do whatever you want. Well, not everything you want. I did a video on this. There are names that you aren't allowed.

[Hannah Fry]

Sure.

[Michael Stevens]

You know what? Funny enough, a name is a human right. The UN has said that a name is a right that you have as the human. So, yeah, it's a human rights abuse to not name children.

[Hannah Fry]

Wow. Yeah. I mean, it's legal requirement, right? Should I tell you some of the stuff that he. He told me? Because the thing is, is that this whole idea of not feeling pain, especially if you live with chronic pain, I think it feels like, oh, this would be such a blessing. But it is the most horrific curse. The most horrific curse. So they found out that he had this condition when he was a baby and he was teething. I mean, as I was talking to him, I sort of noticed that his speech was impaired slightly. And basically what had happened when he was teething was he had bitten off a chunk of his own tongue and not even realized. They diagnosed him by holding an open flame underneath his foot. And he didn't flinch like this is a little baby, right? Keeping a tongue, toddler, say full stop, it's quite difficult. But like when they're not feeling pain, he would sort of use it as a way to get what he wanted. So if his parents, you know, as a teenager were like, you need to do this, he'd be like. And would sort of sit there and break his fingers just to.

[Michael Stevens]

Oh, no. Wow.

[Hannah Fry]

The mortality rate of people with this particular mutation is incredibly high. Lots of them die in childhood, particularly historically, and if not, you know, in their teenage years. It's really, really, really not nice. You know, if you want real proof of like the fact that not having any pain at all is like such a horrific curse. Leprosy, which people had historically thought was a condition which rotted flesh. Actually in the 1940s there was a surgeon called Paul Brand who discovered that actually that's not what it is at all. All it does is a bacteria that kills the nerves. So means that you cannot feel pain and thus it's your own actions effectively that mean that you lose toes, you lose fingers. These are self inflicted wounds that are unfelt, essentially. There's a really horrible story about him going to India to a leper's colony to sort of study people. And at nighttime he would have to stay up to sort of fight the rats away from kind of chewing on people who were asleep because they just couldn't feel it. They couldn't feel the pain.

[Michael Stevens]

Whoa. I didn't know that about leprosy. I know that there's like wet and dry leprosy, or at least that's what they were called back at the time of Papillon. Have you ever seen that movie?

[Hannah Fry]

No.

[Michael Stevens]

There's a really cool scene where Papillon, an escaped prisoner, is trying to find a safe harbor and he comes to a leper colony and they're going to kick him out. And they're like, we'll let you stay if you smoke from my cigar. So the idea is like, oh, it's contagious. He's going to. But he grabs the cigar anyway and he smokes from it and gives it back. And the guy goes, how did you know that I didn't have contagious wet leprosy? And Papillon goes, I didn't. I'm just that destined. It's just worth the gamble for you to protect me. Yeah, it's a very cool scene.

[Hannah Fry]

So hold on. Wet leprosy is contagious and dry is not.

[Michael Stevens]

That's at least what I learned from the movie and I Have not looked deeper into it, but I do think it is true that there is a contagious and non contagious version.

[Hannah Fry]

But I mean, it's a bacteria that causes it. So presumably, I mean, it's not a particularly prevalent disease, at least in the western world now. Right. It's not something that you have to particularly be concerned about.

[Michael Stevens]

Yeah, I haven't run into it. Oh, you're right. Yeah. Nerve damage may result in the loss of nociception.

[Hannah Fry]

There you go.

[Michael Stevens]

Let me just look up contagiousness. Okay, so all I'm seeing here is that leprosy is not highly contagious. They can live with their families and attend school and work. This is right from Wikipedia. So I don't know if there's two different kinds. All I know is that in the movie Papillon and maybe also in the movie.

[Hannah Fry]

It's a documentary.

[Michael Stevens]

It was supposed to be a bit of a documentary. It's based on the guy's life story that he wrote. But anyway, pain. So I, I didn't know leprosy was related to the loss of nociception.

[Hannah Fry]

I mean, the main thing that I know about leprosy is from being a Catholic. Right. Because, boy, do they talk about it a lot in the Bible.

[Michael Stevens]

A lot of people get it.

[Hannah Fry]

Yeah, a lot of people get it in the Bible. There's something really interesting here, which is that when you look at the origin of the word pain, it's like a curse, but actually the real curse is not having it at all. Yeah, the sort of perception of what pain is and what it is kind of doing for us, not only that has changed, but like how you can measure it itself. Because there have been people who've been like, right, well, let's just create a scale here. Let's just create numbers where 10 means something, a particular type of pain. And then we'll just be able to. Everyone will be able to scale it. Right. So there was the dollarimeter, which is a lamp that would focus on a sort of blackened patch of forehead. And then the idea was that there would be like a unit of agony. The doll scale, naught to 10.5, which is, I think, frankly upsetting that it goes to 10.5. But at eight dolls, it would leave second degree burns on the skin. But it was just a bit all over the place. And what they tried to do, they tried to calibrate this with different people. They would go in when people were in labor, when women were in labor, they would go in an in between contractions they would try and, like, burn their hands.

[Sponsor/Ad Voice 1]

Oh.

[Hannah Fry]

And ask how it compared. It's like, well, what hurts more, this or the actual childbirth?

[Michael Stevens]

How many doles are you feeling right now?

[Hannah Fry]

How many dolls? And I'm quoting here, one subject became so hostile, which you would, that they. They abandoned her. Anyway, the point is they tried this, right? But the numbers never reproduced. They couldn't find. They couldn't manage to extract, like, a level of heat that then correlates to a certain number on the scale.

[Michael Stevens]

No, it would. It would depend way too much on the set and setting. You know, like. Like we've said, if someone was more stressed, they're gonna feel it differently than if they're focused or. Or chill. It's gonna matter whether their hair is red or not, apparently.

[Hannah Fry]

Right. But the point that you just made about how you're feeling being such. This integral key part of it. It is, as it turns out, almost all of the story is what's going on in your head. There was, like, some early indications of this when people were studying this, particularly during war settings, right? So, like, In World War II, there'd be soldiers who had these catastrophic wounds who are kind of getting up and walking around and, like, apparently feeling nothing. And there is actually a physical mechanism that can cause that. So there is this kind of descending control system. So it's not that you just have pain happens here. It goes straight to your brain, actually. You kind of have this gateway through the spinal cord. And what can happen is your body can effectively, like, close the gates in the spinal cord before you've ever actually felt anything. This. This, by the way, is one of the reasons why, if you have a kid who falls over and then you're like, oh, rub your knee, right? You can actually help, because if you have, like, a harmless touch, then it can help to confuse the signal and basically stop it reaching your brain. It kind of closes the gate when it gets to your. When it gets to your spinal cord column.

[Michael Stevens]

That makes sense.

[Hannah Fry]

But there is some amazing research in Oxford University by Irene Tracy, who I've gone to go and meet. She's amazing, by the way. She is known as the Queen of Pain. What a title.

[Michael Stevens]

What a great title.

[Hannah Fry]

She has this lab, which she cheerfully calls the torture chamber, where she has different ethical ways in which to inflict pain on people. So she stabs people with needles. She burns them with, like, chili pepper on the skin. It's like cutting, burning. What the other ones? Stinging.

[Michael Stevens]

Thermal grilling.

[Hannah Fry]

Thermal grilling. She doesn't thermal grill or at Least I didn't see her thermal grill. I think she was actually just causing genuine pain. But she does this to people when they are inside of an MRI scanner. And what they can do is they can inflict a kind of discrete, measurable amount of pain with these needles that have, like, particular pressure. So you know that the physical sensation, or at least the cause of the physical sensation, is kind of very well controlled between people. And then you can see how people construct or react to that sensation in their brains, depending on what particular state they're in. And you're absolutely right that basically the more stressed you are, the worse it is, the more relaxed you are, the easier it is. The more that you've had experience of pain in the past, the easier it is, the more that you think that the pain signifies something dangerous, the worse that it is.

[Michael Stevens]

Yeah.

[Hannah Fry]

But like, all of these things end up really contributing to your experience of what is actually going on.

[Sponsor/Ad Voice 6]

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[Michael Stevens]

If I am worried about it, I'm going to think about it a lot more. Which also might explain why kids can be so much more affected by what seems like it shouldn't hurt as much as their acting. But, I mean, it's the first time they've felt that.

[Hannah Fry]

Yeah.

[Michael Stevens]

And they're so powerless. Like, of course this is a big deal.

[Hannah Fry]

Right.

[Michael Stevens]

And it also makes sense how your pain will lessen when help arrives because you no longer need to be as careful or cry out for help. It's arrived. It's not necessarily a placebo effect. It's just a straight up your body going, okay, phase one is over. Now we'll begin phase two.

[Hannah Fry]

It is just a straight up actually. It's okay, you're safe.

[Michael Stevens]

Yeah.

[Hannah Fry]

There was one thing that I used to do with my little girls when they were really young. I tried to teach them that when they would fall over to immediately do jazz hands.

[Michael Stevens]

Oh.

[Hannah Fry]

To sort of make it into a happy moment. Because I think that they really feed off of your reaction to something. I think if you are like, oh, no, this is serious, then it's like the panic arises and all of a sudden it becomes a really, really big deal. Whereas if you are like happy and clappy and it's like, hey, no big deal, let's crack on. We' still playing. It's not just that they ignore the pain. It's that the actual pain that they feel is lower.

[Michael Stevens]

That's right.

[Hannah Fry]

I think that's really it here. We're not talking about placebo. I mean, placebo feeds into this a little bit in the sense that you're tapping into the same thing. But what we're really talking about here is you actually feel it differently. Like, your physical sensation is different depending on how you're feeling.

[Michael Stevens]

So is there a way to measure pain at all? I mean, I know we have those, like, scale of 1 to 10, you know, point to the smiley face. Which one are you? I guess that works because it's a subjective thing. But we can't build a painometer, plug it into your brain and go. Or plug it into your nerves and go, ah, nah, there's no pain.

[Hannah Fry]

In the same way that we can't build a deliciousometer.

[Michael Stevens]

Right.

[Hannah Fry]

Or like a happy ometer.

[Michael Stevens]

A love ometer. Which of your cats do you love more? We're gonna find out today using our love ometer. It never goes wrong.

[Hannah Fry]

It just doesn't work. It doesn't. I mean, at the same time, we do know lots of things about it. Like, we know that your belief changes it, but we also know that your memory about it afterwards changes.

[Michael Stevens]

True.

[Hannah Fry]

We know that you don't store it as, like, a running total. You store it as, like, a peak and the end. This is some Kahneman work. He was researching colonoscopies. Colonoscopies are not very nice. They're not very comfortable. Fortunately, never had one. But, you know, my understanding is that it's just not a very nice experience to be part of of. But they were talking about people's perception of the pain when the probe was removed immediately afterwards, or when the probe was really slowly removed and then sort of paused before the final removal. And actually, even though the whole process was lengthened was a longer period of time with the gentle removal. People's memory of the colonoscopy was that it was less painful when the ending wasn't so bad.

[Michael Stevens]

Right, of course. Yeah. No, when I'm thinking of times I've been in pain, I don't remember the middle of it. I remember, like, how it started, how it felt after. But, yeah, that's interesting. The way I remember my pain is not the way I remember a movie.

[Hannah Fry]

No, it's not. It's the peak and the end. That's essentially what you. What you remember. The thing about this. This idea that your brain is giving you kind of free analgesia. Right. I think there's something really extraordinary in that because I think for the last 150 years or so, what science has done in the pursuit of mitigating pain has been, okay, take this drug. You know, we'll compare it against the placebo but let's see how much extra this drug gives you compared to placebo. And kind of all of the focus has been in on that. And in a lot of ways, I feel like we've sort of thrown away the half or maybe more. That actually makes a really gigantic difference, which is much more woo woo, I'll admit. You know, it's much more sort of like softly, softly, like huggy feelings. But it's also the bit that doesn't come with any side effects.

[Michael Stevens]

Yeah, it's woo woo adjacent. And I'm glad that we're taking it more and more seriously because here's some Something weird I heard when I was at McGill University. Acetaminophen in America, what we call Tylenol, especially Tylenol.

[Hannah Fry]

Paracetamol in the UK we call it.

[Michael Stevens]

Right. So since Tylenol entered the market, it has become more effective at reducing pain as a pain reliever. It's gotten better. The chemical formula has not changed. So there's this open question. What's happening? Are our bodies changing? Have we evolved to work better with Tylenol? The best answer seems to be that no. We just trust that it will help the pain more. Now when it was first introduced, people thought, I don't know. Now we just go right to the Tylenol. You take it and you feel better because your brain goes, it's gonna work.

[Hannah Fry]

Yeah.

[Michael Stevens]

So the placebo effect has become more powerful.

[Hannah Fry]

I think that we can do a whole other episode on the placebo effect specifically. But it's more than just the sort of illusion, as it were, of, like, feeling like you're being cured. This is actual, like, physiological facts. Right. Which is that pain is not a deterministic thing. It is a sensation that is constructed by your brain, subject to your entire experience. Yeah, I do sort of think we've been kind of ignoring that a little bit. As I've mentioned on this show before, I had cancer a few years ago, and I always think that actually the doctors might have cured me, but the nurses made me better.

[Michael Stevens]

Oh, interesting.

[Hannah Fry]

And I think that is it, right? Like, the nurses were the ones who actually made me feel like it was gonna be okay. You know, they were the ones who were there, like, with the tea and sympathy. They were the ones who were, like, calmly and carefully helping me through the process of, like, removing all the tubes and what, you know, all of this stuff. And. And I think that what they were doing, a really, really good nurse is one who knows how to tap into your brain's free analgesia.

[Michael Stevens]

They do. That's what makes them good nurses. I think that effect extends to all kinds of other professions. I feel like physics keeps me safe on an airplane.

[Hannah Fry]

Yeah.

[Michael Stevens]

But the flight attendants make me feel safe. I know that the plane can deal with this amount of turbulence, but when I look at the flight attendants and they're like, not even paying attention to it. They're just doing their own thing, looking annoyed or whatever, I'm like, thank goodness. I'm so much less worried because you are. I'm like, mirroring your behavior. Pain is definitely a social phenomenon, a phenomenon of the mind and not just the brain.

[Hannah Fry]

Totally agree. At the same time, the last thing I want to tell you about is. So I guess there's like the different places to target pain. And if. And as I said, if you are someone who suffers from chronic pain, it's like, well, that's all very good, but, you know, I can't just, like, wish myself better. And I agree. It's like, it's really, really difficult to do this. You do also want sort of effective pharmaceuticals. And the thing about, like, all of the stuff that we have really, you know, opioids being the most effective at blocking the pain, it kind of like blocks everything else as well. You can't really function. It's, you know, it's not specific enough. But going back to that nav 1.7, the little gate that allows all of this ions through. So there is some work that is going on now, which is. Okay, well, is there a way that you could design a drug or maybe genetically engineer your neurons? Or is there something that you could do that targets that channel in particular? Right. That little gateway in particular. Because actually, the other way around, it does happen. So, you know, the bullet ant don't.

[Michael Stevens]

No.

[Hannah Fry]

Okay. So this is supposedly. I mean, there's like some crazy scientists, Justin Schmidt was one in particular, who deliberately go out and get themselves stung by absolutely everything in order to rank them. He writes, like sommelier, like, notes for different things. So he says a yellow jacket wasp is sort of hot and smoky, but almost irreverent in the feeling that it gives you. Okay.

[Michael Stevens]

Oh, I love that. Yeah. Yeah.

[Hannah Fry]

But the bullet ant is like top dog in terms of how much it hurts. He describes it as a flaming charcoal with a 3 inch rusty nail in your heel burning for 24 hours. Okay. Now the reason why the bullet ant wins in terms of pain is because its Venom actually attacks NAV 1.7. Like the exact same channel. Yeah. And so what it does is it just jams the gate open effectively so that your pain nerves just fire over and over and over and over and over and over and over again and won't switch off. You're doing the exact opposite of what happens with the people who feel no pain whatsoever. This gate is like wide open as opposed to completely closed.

[Michael Stevens]

But yet the bullet ant bite is not probably any more dangerous than a black widow, which might not hurt nearly as much and yet is so much more potentially lethal.

[Hannah Fry]

Right. Just because of this very particular sort of biological formulation. And so the question is, can you do something that directly targets that NAV 1.7? And some people have tried, right? They tried, they tried. I definitely shouldn't laugh about this because it would be amazing if you could. There are different drugs that people have constructed and there was one of them that actually looked like it was going to be really promising. That would target NAV 1.7, which close that channel and then you could choose to turn on and off pain. Unfortunately, NAV 1.7 is also really close in design in sort of the way it's structured to NAV 1.5, which is absolutely critical to maintaining a heartbeat.

[Michael Stevens]

Oh, my God.

[Hannah Fry]

So if you get even a slightly bit wrong, you just start end up closing the pathways, closing these gates that allow your heart to beat.

[Michael Stevens]

That's unfortunate.

[Hannah Fry]

That is unfortunate. But all the same, I think as we are getting further and further into really amazing molecular biology design, sort of synthetic biology, this is, I think the hope, right, is that there will come a point in the future where we can create something that allows you on demand to take some kind of pharmaceutical that just switches off that NAV 1.7 when you need it and not when you don't.

[Michael Stevens]

Right. So this could have less addictive potential than opioids. It could help people with chronic pain. Pain as well.

[Hannah Fry]

Exactly.

[Michael Stevens]

But there's always the balance of you need some pain, you need to know what's going on with your body, but when it's not helpful, it's not helpful.

[Hannah Fry]

Exactly. Okay, so I guess to sum this up then, pain isn't this payment, right? The word says that it's a punishment, but the actual mechanism itself is, I think, more of a gift, actually. This verdict that your brain is creating this kind of call, this decision that is being made on your behalf path and honestly, mostly in your favor. It's just unfortunate that for some people that that message keeps on, keeps on blaring even when it should.

[Michael Stevens]

But its intentions are good.

[Hannah Fry]

Its intentions are good, but we know

[Michael Stevens]

what's paved with good intentions.

[Hannah Fry]

So very true. The Road to Hell okay, I guess that brings us to the end of this episode of the Rest of Science. Thank you very much for staying with us all to this, but look at you guys. Look at you go. You're the real ones. You know I'm painless, honestly.

[Michael Stevens]

These yeah, thanks for listening. We really appreciate all of your support and especially your questions. Please keep them coming in. The rest is science. Goal hanger.com See you next time. Bye.

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[Hannah Fry]

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