WEBVTT - How Pain Works 0:00:01.120 --> 0:00:03.560 Welcome to Stuff You Should Know, a production of five 0:00:03.600 --> 0:00:12.640 Heart Radios How Stuff Works. Hey, and welcome to the podcast. 0:00:12.680 --> 0:00:15.480 I'm Josh Clark. There's Charles W. Chuck Bryan over there, 0:00:16.239 --> 0:00:19.000 and Jerry's out there running around somewhere. We just gave 0:00:19.000 --> 0:00:22.040 her a hot foot. It's hilarious. Uh, and this is 0:00:22.079 --> 0:00:28.520 stuff you should not tried. Are continuing exploration of pain? Mhm. 0:00:29.400 --> 0:00:31.760 What else have we talked about with paint? We did 0:00:31.760 --> 0:00:34.519 one on the pain scales, okay a couple of years ago, 0:00:34.680 --> 0:00:39.760 and uh, then we did one on something about perceiving pain. Well, 0:00:39.800 --> 0:00:43.920 this one, this one, this is just totally stuff you 0:00:43.960 --> 0:00:45.720 should know them because we did a bunch of like 0:00:45.800 --> 0:00:47.840 more niche stuff and now we're going back and doing 0:00:47.880 --> 0:00:53.840 like the umbrella topic and we're talking about pain, which, Um, 0:00:53.920 --> 0:01:00.520 is there a super ancient old evolutionary Um, right, I 0:01:00.560 --> 0:01:05.040 guess that's shared basically throughout all living things. I would 0:01:05.080 --> 0:01:08.680 say it's a pretty fair guess. I think so, Yeah, 0:01:08.720 --> 0:01:12.760 because um, there's something that pain pain specifically, which is this. 0:01:13.120 --> 0:01:15.319 We'll get into defining it and how hard that is 0:01:15.319 --> 0:01:18.959 in a second, but um, it seems to be a 0:01:18.959 --> 0:01:24.919 a fairly universal, almost universal process where our body says, hey, 0:01:24.959 --> 0:01:28.360 there's something really bad going on, say on your hand, 0:01:28.640 --> 0:01:30.600 So move your hand away from wherever it is in 0:01:30.680 --> 0:01:33.560 space right now, and hopefully that will help keep it 0:01:33.600 --> 0:01:38.720 from getting further damage. Like pain is a signal saying, um, 0:01:39.040 --> 0:01:41.880 do something, dummy, move and it's it. I mean, that's 0:01:41.959 --> 0:01:44.479 that's you know, you see it in and basically any 0:01:44.480 --> 0:01:48.440 animal we've ever encountered, including the beaver and the porcupine. 0:01:49.040 --> 0:01:51.320 That's right. And by the way, we did other people 0:01:51.360 --> 0:01:56.160 who can't feel pain ten years ago. Yeah, it actually 0:01:56.200 --> 0:01:59.120 seems longer ago than that. That's funny because I thought 0:01:59.120 --> 0:02:02.960 pain Scales was forever ago and it was so Yeah, 0:02:03.240 --> 0:02:06.480 I have no sense of time anymore. So, so we 0:02:06.520 --> 0:02:08.600 are talking about pain, Chuck, you feel pain right or 0:02:08.639 --> 0:02:11.800 do you have a high pain threshold? Are you sensitive? Uh? Well, 0:02:11.880 --> 0:02:13.399 you know it's funny because I went back and listen 0:02:13.440 --> 0:02:15.280 to the Pain Scales and I kind of chatted about 0:02:15.320 --> 0:02:18.040 that for a bit. But I have a pretty high 0:02:18.040 --> 0:02:24.760 pain threshold. Yeah, okay, I would say mine's average. Let's 0:02:24.760 --> 0:02:26.359 just go with that. I wonder what I said in 0:02:26.400 --> 0:02:29.160 the Pain Scales app because there's no way I didn't 0:02:29.200 --> 0:02:33.080 respond to your your thing you know it will be 0:02:33.080 --> 0:02:37.960 a mystery. So um. Apparently pain is the most common 0:02:38.000 --> 0:02:43.160 reason that people, um go seek medical attention. But when 0:02:43.160 --> 0:02:45.239 they go seek medical attention, as we talked about in 0:02:45.240 --> 0:02:47.280 the pain Scales episode, the whole reason there is such 0:02:47.280 --> 0:02:49.600 a thing as a pain scale is because it's a 0:02:49.680 --> 0:02:55.360 fully subjective experience and it's really difficult to describe. And 0:02:55.400 --> 0:02:58.120 it's taken medicine, like many, many years to get to 0:02:58.160 --> 0:03:02.880 a point where they tell the people their training, doctors 0:03:02.880 --> 0:03:06.840 and nurse practitioners and medical staff, like, if somebody tells 0:03:06.840 --> 0:03:09.800 you they're in pain, they're experiencing pain, you have to 0:03:09.840 --> 0:03:13.120 take them at their word. Um. And that's actually kind 0:03:13.160 --> 0:03:15.720 of a new development because there are plenty of times 0:03:15.720 --> 0:03:18.960 when it appears that there's absolutely nothing wrong and that 0:03:19.040 --> 0:03:22.080 the person shouldn't be in pain. And for years doctors 0:03:22.120 --> 0:03:26.160 just kind of treated people like like that like kooks 0:03:26.800 --> 0:03:28.919 and didn't believe them, which was very sad. And now 0:03:28.919 --> 0:03:31.640 we're finally figuring out there's situations where you can be 0:03:31.680 --> 0:03:34.360 experiencing pain even though there's no reason for you to 0:03:34.400 --> 0:03:38.360 be experiencing pain, which really underscores just how subjective it is. 0:03:38.880 --> 0:03:42.280 That's right. Uh. In three, there was an actual definition 0:03:43.000 --> 0:03:45.600 for pain that was introduced that has a couple of 0:03:45.640 --> 0:03:48.760 really important caveats that will kind of play out through 0:03:48.760 --> 0:03:54.000 this episode. Pain is an unpleasant, sensory and emotional experience. 0:03:54.120 --> 0:03:57.960 There's the first caveat associated with actual or potential tissue 0:03:58.040 --> 0:04:03.000 damage or described in terms of such damage, which is 0:04:03.040 --> 0:04:06.760 a big caveat there, because you can walk into a 0:04:06.840 --> 0:04:11.000 doctor's office and say, I've got some big time tissue damage. Doc, 0:04:11.640 --> 0:04:13.840 I'm experiencing big time pain, and they can look you 0:04:13.840 --> 0:04:16.440 over and be like, this guy didn't have any tissue 0:04:16.480 --> 0:04:20.000 damage at all. So that's in the actual definition of 0:04:20.040 --> 0:04:22.720 pain of pain. So I think that the reason they 0:04:22.720 --> 0:04:27.000 caveatted that was for the very simple reason that pain 0:04:28.160 --> 0:04:32.040 can be emotional. And I don't mean like real emotional pain. 0:04:32.080 --> 0:04:35.200 I mean a physical pain that is may be made 0:04:35.240 --> 0:04:39.680 worse by emotion or brought on by emotion, or that 0:04:39.760 --> 0:04:42.159 you're you know, you really don't have a pain, like 0:04:42.160 --> 0:04:45.320 you've got a chronic pain, let's say, but nothing's going 0:04:45.360 --> 0:04:47.880 on under the hood to cause it. Yeah, And like 0:04:48.520 --> 0:04:51.240 we've learned so much about pain since nineteen seventy three 0:04:51.240 --> 0:04:54.800 that I saw that just this past July, um the 0:04:54.880 --> 0:04:58.360 International Association for the Study of Pain updated and revised 0:04:58.360 --> 0:05:01.080 their their definition. It's still basically the same, but they've 0:05:01.120 --> 0:05:03.360 included a lot of stuff that we talk we're going 0:05:03.400 --> 0:05:05.920 to talk about in this episode. Does it say pain 0:05:06.200 --> 0:05:14.640 whatever you say, dude, right yea, they said pain is uh, yeah, 0:05:14.960 --> 0:05:18.240 it is so far at least. Um. There's a bunch 0:05:18.240 --> 0:05:21.080 of different types of pain, though actually not that many, 0:05:21.240 --> 0:05:26.719 but there's a few. Acute pain, which is very short lasting. 0:05:26.760 --> 0:05:29.400 If you if you put your finger on the burner 0:05:29.400 --> 0:05:32.240 of the stove or something like that, or um, slam 0:05:32.240 --> 0:05:34.239 it in a window, that's going to be an acute 0:05:34.279 --> 0:05:37.960 pain where you know it's really helpful, so you know 0:05:38.080 --> 0:05:40.240 your body is gonna say, wait a minute, that's super hot. 0:05:40.839 --> 0:05:42.760 Or by the way, dummy, you just put your finger 0:05:42.800 --> 0:05:46.520 in a window and you immediately have a reaction to 0:05:46.560 --> 0:05:50.240 stop that immediate acute thing from happening, even though the 0:05:50.240 --> 0:05:52.760 pain is gonna still be there. It's not like you 0:05:52.760 --> 0:05:55.640 slam your finger in the window, yank your thing away 0:05:55.640 --> 0:05:57.880 and shake it a little bit and it's gone. Right. Well, 0:05:57.880 --> 0:05:59.640 it can be depending on the level of pain, but 0:05:59.680 --> 0:06:01.960 it makes sense that it would still linger even in 0:06:02.040 --> 0:06:04.200 acute paint, which from what I can tell, is like 0:06:04.560 --> 0:06:06.919 the ideal version of pain. It's, like you said, it 0:06:06.960 --> 0:06:09.320 makes you stop doing whatever you're doing, but the fact 0:06:09.360 --> 0:06:11.800 that it still hangs around for another minute, it's almost 0:06:11.839 --> 0:06:14.159 like it's teaching you a lesson, like not only stop 0:06:14.240 --> 0:06:17.600 doing that, don't do that again. Yeah, and there's some 0:06:17.680 --> 0:06:20.080 overlap in these, by the way, So when we talk 0:06:20.120 --> 0:06:24.040 about the next one, no susceptive pain, this comes about 0:06:24.080 --> 0:06:28.080 from tissue damage, like real tissue damaged by like physical 0:06:28.160 --> 0:06:31.320 or a chemical agent. We're talking a chemical burn, or 0:06:31.360 --> 0:06:34.920 a trauma or a surgery. This can also include slamming 0:06:34.960 --> 0:06:38.240 that finger in the window. It can also include you 0:06:38.320 --> 0:06:40.120 worked out really hard the day before and you're really 0:06:40.160 --> 0:06:42.640 sore the next day. Yeah, as long as there's some 0:06:42.680 --> 0:06:47.479 sort of like mechanical reason or some sort of damage 0:06:47.520 --> 0:06:50.640 to tissue, or even temporary damage like a sore sore muscle. 0:06:51.040 --> 0:06:54.039 Um And it also includes malignant pain, which is cancer pain, 0:06:54.320 --> 0:06:58.159 which is where tumor starts growing in your tissue, impresses 0:06:58.200 --> 0:07:00.920 on nerves and blood vessels and create pain like that. 0:07:01.440 --> 0:07:04.200 And no, no susceptive pain is what most people think 0:07:04.240 --> 0:07:07.320 of when they think about pain. Um And it can 0:07:07.360 --> 0:07:10.680 be both acute and chronic. But I guess the best 0:07:10.720 --> 0:07:13.040 way to kind of differentiate no susceptive pain from the 0:07:13.080 --> 0:07:16.840 rest of it, there's actually something going on that is 0:07:16.920 --> 0:07:21.120 causing the pain signal to be created. Um And it, 0:07:21.400 --> 0:07:24.600 like I said, it can be short lasting or long lasting. Um. 0:07:24.640 --> 0:07:28.640 And it's different from a different type of pain, appropriately 0:07:28.760 --> 0:07:33.520 enough called neuropathic pain. Whereas no susceptive arise from arises 0:07:33.520 --> 0:07:38.360 from tissue damage, neuropathic arises from damage to the actual 0:07:38.480 --> 0:07:41.640 nerves themselves. Yeah. Like, uh, I don't know if you 0:07:41.640 --> 0:07:44.360 remember this story from almost a year ago. It was 0:07:44.440 --> 0:07:48.440 last October when I hit my shin on my bed 0:07:48.840 --> 0:07:52.960 so hard that water started leaking out of my eyes. 0:07:54.000 --> 0:07:57.640 I wasn't crying, it was just literally water coming out 0:07:57.640 --> 0:08:00.360 of my eyes. And I've never felt pain like that before. 0:08:00.400 --> 0:08:03.720 And it was clearly some kind of literal nerve damage 0:08:03.760 --> 0:08:07.520 because for three or four months, I had like a 0:08:07.600 --> 0:08:10.920 three uh three inch by three inch square on my 0:08:10.960 --> 0:08:14.680 shin that was completely numb. And uh, it's it's the 0:08:14.720 --> 0:08:17.600 worst pain, like physical pain I've ever felt in my life. 0:08:17.880 --> 0:08:20.520 They I mean, that would definitely qualifies neuropathic pain. You 0:08:20.600 --> 0:08:23.840 clearly messed up the nerves in that little area. UM, 0:08:23.920 --> 0:08:26.360 and you're lucky that it only lasted three months, because 0:08:26.360 --> 0:08:29.520 apparently neuropathic pain, which can include everything from hitting your 0:08:29.520 --> 0:08:33.160 shin to banging your funny bone, your elbow UM two 0:08:33.200 --> 0:08:38.160 things like sciatica or even multiple sclerosis. Anytime the neurons 0:08:38.200 --> 0:08:42.880 in your nerve fibers are are damaged. UM, that's neuropathic pain, 0:08:43.080 --> 0:08:45.760 and it can last. It can very easily translate from 0:08:45.800 --> 0:08:48.800 acute pain over to chronic pain, which is pain that 0:08:48.880 --> 0:08:52.640 last six months or longer um, which can itself be 0:08:52.679 --> 0:08:57.480 no susceptive or neuropathic. Uh. It can also, unfortunately be psychogenic. 0:08:57.600 --> 0:09:02.240 Chronic pain can be, which is where you have lasting, uh, 0:09:02.600 --> 0:09:06.679 sustained pain over six months or longer um for no 0:09:06.760 --> 0:09:10.520 good reason whatsoever. Yeah, and this is you know, it 0:09:10.520 --> 0:09:14.120 gets really sort of murky and confusing. Here. We are 0:09:14.200 --> 0:09:16.400 not saying that chronic pain is all in your head, 0:09:17.040 --> 0:09:20.880 but we're saying that in some cases that there there 0:09:20.960 --> 0:09:24.360 is no reason behind you continuing to feel chronic pain. 0:09:25.520 --> 0:09:28.160 But so many people suffer from chronic pain. I think 0:09:28.760 --> 0:09:31.280 roughly it kind of varies, you know, depending on the year. 0:09:31.320 --> 0:09:36.280 But somewhere in the neighborhood of twenty adult Americans suffer 0:09:36.360 --> 0:09:41.680 chronic pain every single year. Um, And it's when you 0:09:41.679 --> 0:09:44.920 hear people talk about that, like, uh, I just feel 0:09:44.920 --> 0:09:46.480 bad for him. I can't imagine what it's like to 0:09:46.520 --> 0:09:49.520 walk around in constant pain, and it's probably even more 0:09:49.559 --> 0:09:54.080 frustrating when a doctor can't trace it to a thing like, hey, 0:09:54.160 --> 0:09:57.400 we fixed that. It shouldn't be hurting anymore, right, especially 0:09:57.400 --> 0:10:00.600 if they're being patronizing and treating you like your cook, Well, 0:10:00.840 --> 0:10:03.959 that's a bad doctor. You should not go. Sure, But again, 0:10:04.000 --> 0:10:07.240 I mean, like I feel like people with fibromyalgia or 0:10:07.320 --> 0:10:09.679 chronic fatigue. I don't know if you experience pain with 0:10:09.760 --> 0:10:12.839 chronic fatigue, but have long been treated like their nuts, 0:10:12.880 --> 0:10:15.120 like it's all in their heads, just because you know, 0:10:15.360 --> 0:10:17.800 science has not been able to identify exactly what the 0:10:17.800 --> 0:10:21.200 deal is. Yeah, I would say, if your doctor is 0:10:21.240 --> 0:10:23.440 like that, go to a doctor with a little better 0:10:23.480 --> 0:10:26.200 bedside manner. At least they might be saying the same thing. 0:10:26.760 --> 0:10:30.079 But they would should treat you with respect. And if 0:10:30.280 --> 0:10:33.280 if they're wearing oversized clown shoes, so much the better. 0:10:33.559 --> 0:10:35.960 That's usually it did give way for a great doctor, 0:10:36.520 --> 0:10:40.360 that's right. Um, I don't think we said that, uh, 0:10:40.600 --> 0:10:43.880 we we talked about no susceptive pain, but no susception 0:10:43.960 --> 0:10:48.439 is taken from the Latin word for hurt, and um 0:10:48.559 --> 0:10:51.600 pain is its own thing like pain perception. We're talking 0:10:51.640 --> 0:10:54.880 about what's going on with the central nervous system, uh 0:10:55.320 --> 0:10:59.240 the peripheral central nervous system as well, and how it 0:10:59.320 --> 0:11:06.560 processes this information is really uh interesting and still cloudy 0:11:06.600 --> 0:11:09.840 because the brain is involved. And we've done dozens and 0:11:09.880 --> 0:11:12.240 dozens of podcasts that involved the brain, and at some 0:11:12.280 --> 0:11:15.320 point during all of them we usually say something like, 0:11:15.520 --> 0:11:17.319 this is kind of their best guess right now, because 0:11:17.320 --> 0:11:20.160 the brain is still such a mystery. Yeah, we have 0:11:20.400 --> 0:11:23.320 made like advances by leaps and bounds since the sixties 0:11:23.360 --> 0:11:25.760 when we kind of started to change our understanding of 0:11:25.760 --> 0:11:28.679 pain and definitely refining it. But one of the things 0:11:28.760 --> 0:11:33.120 we figured out is that no susception itself is separate 0:11:33.160 --> 0:11:36.680 from the experience of pain. It's like the body giving 0:11:36.840 --> 0:11:40.559 the brain information about something that's going on with your 0:11:40.559 --> 0:11:44.400 body right now, but it's not pain itself. Pain is 0:11:44.520 --> 0:11:49.760 the brain responding to that information, and so no susception, 0:11:50.040 --> 0:11:53.160 as we'll see, is kind of this process where your 0:11:53.200 --> 0:11:57.960 body um detects some sort of noxious stimuli UH, and 0:11:58.040 --> 0:12:00.920 the no susceptors your specific kind of UM little sense 0:12:00.960 --> 0:12:04.400 receptors that are tuned to pain. As we'll talk about UM. 0:12:04.480 --> 0:12:06.760 They send a signal to your brain saying, hey, there's 0:12:06.760 --> 0:12:09.320 something going on here, and then in your brain, your 0:12:09.320 --> 0:12:11.679 your brain starts sort through the whole thing and decides 0:12:11.679 --> 0:12:15.560 how to respond. So no susception and pain they're very 0:12:15.640 --> 0:12:18.400 much intertwined, but they're definitely different things, and we've actually 0:12:18.480 --> 0:12:21.400 seen that one can exist without the other. Yeah, I 0:12:21.400 --> 0:12:24.760 mean they've done studies that UM and I. I mean 0:12:24.800 --> 0:12:26.600 we had to have talked about this and other people 0:12:26.600 --> 0:12:32.640 that can't feel pain UM congenital analgesia. I don't remember 0:12:32.679 --> 0:12:35.400 ever saying those words before. I think we had to 0:12:35.440 --> 0:12:40.160 have There's no way, although knowing us, it's possible we 0:12:40.240 --> 0:12:43.800 walked around that one. Well maybe so. But there are studies, 0:12:44.160 --> 0:12:47.120 including ones on that people who can't feel pain, that 0:12:47.200 --> 0:12:51.040 have shown that no susception can occur without the experience 0:12:51.040 --> 0:12:54.120 of pain, and UM pain can be experienced with the 0:12:54.160 --> 0:12:56.679 absence of no susception. So it's sort of a two 0:12:56.720 --> 0:12:59.439 way street. Yeah, that's like that psychogenic pain where you 0:12:59.559 --> 0:13:02.320 there's no reason for you to be feeling that pain 0:13:02.440 --> 0:13:05.840 right then, right, yeah, And because it's the brain, it's 0:13:05.960 --> 0:13:08.920 um and you put in here it's like it sounds funny, 0:13:09.000 --> 0:13:12.160 but your brain is what's feeling the pain. Like when 0:13:12.200 --> 0:13:16.640 you smash that hand in a window. Um, you might 0:13:16.679 --> 0:13:19.360 think that your hand feeling the pain, but technically it's 0:13:19.360 --> 0:13:22.360 your brain, if that makes sense. Yeah, or even that 0:13:22.440 --> 0:13:26.480 like you're you're that hand that window smashing your hand 0:13:26.840 --> 0:13:31.640 set off a specific unique kind of um uh signal 0:13:32.080 --> 0:13:35.079 that that transmits a pain signal directly your brain. Your 0:13:35.080 --> 0:13:38.120 brain experiences the pain. That's just not quite right. That's 0:13:38.120 --> 0:13:44.160 actually Renee des cartes interpretation of it, and can so well. 0:13:44.200 --> 0:13:46.000 Considering he was working in the first half of the 0:13:46.000 --> 0:13:49.520 sixteen hundreds, he wasn't that far off the mark, especially 0:13:49.520 --> 0:13:53.040 considering that before him the Greeks had thought up basically 0:13:53.080 --> 0:13:55.839 up to day car, everyone had thought, starting with the Greeks, 0:13:55.880 --> 0:13:59.080 that pain was like a spirit intrusion, it was like 0:13:59.160 --> 0:14:01.880 something external at all. And in fact, our word pain 0:14:02.400 --> 0:14:07.480 comes from uh pena like subpoena, which means penalty. So 0:14:07.559 --> 0:14:11.280 this like pain was considered a punishment from the gods 0:14:11.960 --> 0:14:13.560 um And Dave Carr was like, no, I think this 0:14:13.640 --> 0:14:16.559 is an internal process, and he had like the broad 0:14:16.640 --> 0:14:19.680 strokes of it. It's just that he didn't have the 0:14:19.720 --> 0:14:22.640 details that we have now today. Yeah, he kind of 0:14:22.680 --> 0:14:26.520 got well he got one half of it pretty right. Um, 0:14:26.560 --> 0:14:28.680 but I mentioned it was a two way street. It's 0:14:28.680 --> 0:14:30.720 a two way street in a lot of ways. Because 0:14:30.760 --> 0:14:33.920 what we've learned since decart is that we do have 0:14:33.960 --> 0:14:36.240 pain signals that go up from nerves in the body 0:14:36.720 --> 0:14:38.680 to the brain to say hey, I'm hurt. Those are 0:14:38.680 --> 0:14:43.040 called ascending signals. But then we also have another signal 0:14:43.120 --> 0:14:45.440 going I'm just gonna call it downstream for lack of 0:14:45.440 --> 0:14:49.400 a better term, descending signals that come from the brain 0:14:49.960 --> 0:14:53.160 that can kind of mute the pain or turn off 0:14:53.200 --> 0:14:55.920 the pain signals. And that's you know, as we'll see 0:14:56.000 --> 0:14:58.800 later when it comes to medication and stuff. It's sort 0:14:58.840 --> 0:15:02.360 of managing that way, like whatever traffic light is on 0:15:02.360 --> 0:15:04.920 that two way street. Yeah, well that was like a 0:15:05.040 --> 0:15:07.840 huge thing, Chuck, like to figure out that. Wait a minute, Like, 0:15:07.920 --> 0:15:10.840 first of all, the experience of pain is totally in 0:15:10.920 --> 0:15:14.400 the in the brain. Right, your hand itself isn't actually hurting. 0:15:14.440 --> 0:15:17.200 Your brain is hurt is what hurts. It just feels 0:15:17.200 --> 0:15:19.800 like it's coming from your hand. And then secondly, the 0:15:19.800 --> 0:15:24.200 idea that your brain can influence this the experience of pain, 0:15:24.560 --> 0:15:28.200 that was just revolutionary. And so as a result, we've 0:15:28.240 --> 0:15:32.480 come to kind of see pain as the brain. There's 0:15:32.880 --> 0:15:36.040 a neuroscentist name vs. Rama Shan Droton who's just brilliant 0:15:36.280 --> 0:15:40.200 and he um, he said that pain. This is paraphrasing him. 0:15:40.360 --> 0:15:43.480 He said that pain is the brain's opinion of the 0:15:43.480 --> 0:15:46.680 current state of your health. You got no pain, It's 0:15:46.680 --> 0:15:49.640 all good. You've got pain. Your brain is interpreting there's 0:15:49.680 --> 0:15:51.880 something wrong with like your hand or your leg, or 0:15:51.920 --> 0:15:55.920 your guts or something like that. And it's just an opinion. 0:15:55.920 --> 0:15:58.360 And the opinion can be gotten wrong too. Well, you 0:15:58.360 --> 0:16:02.560 know what they say about opinions. Yeah, everybody's got an 0:16:02.560 --> 0:16:04.880 elbow of them. All right, I think we should take 0:16:04.880 --> 0:16:08.320 a break and we're gonna come back and dive into 0:16:08.400 --> 0:16:38.200 some hard science right after this. Alrighty, so your brain 0:16:38.240 --> 0:16:41.360 has an opinion about the current state of your health. Um, 0:16:41.440 --> 0:16:43.840 we're still at the stage where we're sort of testing 0:16:43.840 --> 0:16:47.960 out how pain is generated and how we experience it. 0:16:48.920 --> 0:16:51.080 But what we kind of think right now is what 0:16:51.120 --> 0:16:54.520 we mentioned a little bit earlier is that some of 0:16:54.560 --> 0:16:58.560 the sense receptors located on the nerve endings are really 0:16:58.920 --> 0:17:04.440 finely tuned two different kinds of UM, different kinds of pain, 0:17:04.480 --> 0:17:06.520 but really tuned to different kinds of thing that might 0:17:06.600 --> 0:17:09.800 cause pain, like a hot stove or a needle going 0:17:09.840 --> 0:17:12.040 to your arm. Yeah. And you can pretty much divide 0:17:12.080 --> 0:17:17.960 them into three categories. Mechanical which is pulling, stretching, tearing, cutting, chemical, 0:17:18.280 --> 0:17:21.600 which say like exposure to acid or something, and then 0:17:21.680 --> 0:17:25.359 thermal like like heat or cold. Um. And the idea 0:17:25.400 --> 0:17:30.040 that these no susceptors are capable of being triggered by 0:17:30.200 --> 0:17:33.600 exposure to those kind of stimuli from the external world, 0:17:34.000 --> 0:17:39.359 that that is what kicks off the no susception process. Yeah. 0:17:39.480 --> 0:17:42.119 And they, uh, they're all very different and they have 0:17:42.160 --> 0:17:45.240 different ways of communicating with the brain. Um. There are 0:17:45.240 --> 0:17:48.639 some that do things really really fast. Uh. These U 0:17:48.800 --> 0:17:51.240 there are some called a fibers. They have a little 0:17:51.920 --> 0:17:54.600 it's kind of like a little express train instead of 0:17:54.600 --> 0:17:58.320 having to make stops along the way, has a fatty 0:17:58.480 --> 0:18:04.040 mile in sheath that's going to insulate the electro conduction 0:18:04.080 --> 0:18:06.680 basically on the wire and it really just zaps it. 0:18:06.720 --> 0:18:09.399 They're really really fast not a lot of information losses 0:18:09.440 --> 0:18:14.120 going on. And that's like that first really intense pain 0:18:14.200 --> 0:18:16.399 you feel when you burn your hand or when you 0:18:16.440 --> 0:18:19.600 slam it into the window. Is that's kind of what's 0:18:19.640 --> 0:18:22.040 going on with the A fibers, right, And then you've 0:18:22.040 --> 0:18:28.399 got sea fibers, which aren't insulated and they are slower conducting, 0:18:28.440 --> 0:18:30.760 but they also have a bunch of they recruit a 0:18:30.800 --> 0:18:33.320 bunch of them to conduct signals from different parts of 0:18:33.440 --> 0:18:37.320 different areas um to the brain to say, hey, this 0:18:37.400 --> 0:18:40.399 is this is actually pretty pretty problematic. We got a 0:18:40.400 --> 0:18:42.840 real thing going on here. And they account for the 0:18:43.560 --> 0:18:48.320 follow up like usually burning, throbbing kind of sensation that 0:18:48.480 --> 0:18:51.600 can be followed by that first like bolt of pain 0:18:51.720 --> 0:18:55.480 that the A fibers deliver, and then that's from the 0:18:55.480 --> 0:18:59.800 actual like like uh no susceptors. There's other stuff that 0:19:00.000 --> 0:19:02.600 spens to like if you cut open your hand, those 0:19:02.720 --> 0:19:06.320 damage cells you know, spill their guts and so like 0:19:06.400 --> 0:19:10.560 potassium and glutamate and substance peace starch start like change 0:19:10.640 --> 0:19:14.640 start firing off, like other neurons in the area um 0:19:14.760 --> 0:19:17.840 you might have an inflammatory response, so things like histamine 0:19:17.880 --> 0:19:20.760 show up and they start setting off other nerve fibers too, 0:19:20.760 --> 0:19:25.840 So it's more than just the you know, the cut hand. No, 0:19:26.000 --> 0:19:29.240 susceptor is telling the brain that something's happening. Like a 0:19:29.320 --> 0:19:32.480 whole bunch of different responses from the area are going 0:19:32.520 --> 0:19:35.240 to arrive at the brain and produce this really complex, 0:19:35.440 --> 0:19:39.560 rich message saying here's generally what's going on, and here's 0:19:39.600 --> 0:19:43.600 how bad it is. You ever had a bad burn? Yes, man, 0:19:43.680 --> 0:19:46.239 that's the worst. They are pretty bad. I don't even 0:19:46.320 --> 0:19:50.760 remember what happened, but um, I definitely have burned myself 0:19:50.760 --> 0:19:54.000 pretty bad. You may has this same spot on her 0:19:54.040 --> 0:19:57.359 hand that she gets in like the confection of it. 0:19:57.520 --> 0:20:01.359 Like basically every time it heals, she just re upset again. 0:20:01.440 --> 0:20:03.840 She's always got this little little thing on like I 0:20:03.880 --> 0:20:05.800 think it's her pinky knuckle on her right hand, and 0:20:05.840 --> 0:20:07.880 she always like hits the same spot on the yep. 0:20:08.160 --> 0:20:10.960 Oh man, every time you get that lady a glove 0:20:11.080 --> 0:20:13.479 a hot myth. Yeah, I think by now it's just 0:20:13.520 --> 0:20:17.280 so callous that she is dead. She fights sailors with 0:20:17.320 --> 0:20:21.600 it these days. Yeah, those burns really linger. And that's 0:20:21.640 --> 0:20:24.240 like every time I hear someone or see somebody that 0:20:24.760 --> 0:20:27.119 has has you know, had been in a fire and 0:20:27.160 --> 0:20:29.440 had really really bad burns over a lot of their body. 0:20:29.440 --> 0:20:33.639 I just I can't imagine the lingering pain that they 0:20:33.640 --> 0:20:35.239 go through. I know we've talked about this on some 0:20:35.320 --> 0:20:38.879 episode before, but uh, just those burns that it seems 0:20:38.920 --> 0:20:43.000 like they hurt forever. Yeah, I mean, you've got exposed 0:20:43.000 --> 0:20:46.120 nerves fibers to just the air, which you know, as 0:20:46.119 --> 0:20:52.800 we'll also see, when you undergo a particularly brilliant experience 0:20:52.800 --> 0:20:56.480 of acute pain, it can be so thorough and it's 0:20:56.640 --> 0:21:00.480 energizing of your nerves that they actually become sense of tized, 0:21:01.200 --> 0:21:03.679 so like they become more sensitive than they would have 0:21:03.840 --> 0:21:07.080 before that, which is actually also a problem with with 0:21:07.200 --> 0:21:10.600 chronic pain too. But if you if you experience burns 0:21:10.640 --> 0:21:13.040 like that deep over all of your body, not only 0:21:13.080 --> 0:21:16.000 are you going through the normal pain, you're probably more 0:21:16.080 --> 0:21:19.560 sensitive now to normal stuff like air blowing on your 0:21:19.600 --> 0:21:23.000 exposed nerves than you wouldn't otherwise, and that just makes 0:21:23.000 --> 0:21:25.320 it that much worse. Yeah. And then some things that 0:21:25.400 --> 0:21:29.600 you might think really hurt don't hurt. Um, like cuts, 0:21:29.640 --> 0:21:32.000 I've had cuts before that don't hurt. They might freak 0:21:32.040 --> 0:21:34.760 you out, uh to look at it and to see, 0:21:35.080 --> 0:21:37.320 you know, like your skin exposed and some people are 0:21:37.320 --> 0:21:40.080 really freaked out by the blood. Um, I've had other 0:21:40.119 --> 0:21:42.880 people I know I've never broken bones that have had 0:21:42.920 --> 0:21:45.280 some pretty gnarly injuries like that. That said, it didn't 0:21:45.280 --> 0:21:49.119 really hurt that much. Yeah, they're walking around like a skeleton. 0:21:49.160 --> 0:21:51.200 You hang on the door with their arms just flopping 0:21:51.280 --> 0:21:53.439 back and forth. It's really interesting how it all works. 0:21:53.640 --> 0:21:56.200 But it really underscores, you know, how the brain can 0:21:56.200 --> 0:21:59.280 get its opinion um of what's wrong with the body 0:21:59.320 --> 0:22:02.639 based on the pain information wrong sometimes a lot of times, 0:22:02.840 --> 0:22:05.960 like think about a hangnail. Hangnail is no threat whatsoever 0:22:06.000 --> 0:22:09.520 to your survival, but those things hurt. Or a paper cut. 0:22:10.119 --> 0:22:11.919 No one's going to die from a paper cut, but 0:22:11.960 --> 0:22:15.440 it really really hurts too. Um. It can be overblown, 0:22:15.480 --> 0:22:17.560 it can be underblown, but it really goes to show 0:22:17.600 --> 0:22:21.320 like it's the brain taking all this different information together 0:22:21.400 --> 0:22:24.080 and saying, here's how bad I think this is. Yeah, 0:22:24.119 --> 0:22:28.159 it's pretty cool and painful. Uh. So let's say you 0:22:28.200 --> 0:22:30.920 get hurt. Let's say you you slam your your hand 0:22:30.920 --> 0:22:33.520 in the window like I was talking about, which I 0:22:33.560 --> 0:22:35.080 think has happened. I don't know why I keep going 0:22:35.119 --> 0:22:39.400 to that got your worst fear. I don't know, it's 0:22:39.520 --> 0:22:41.720 I don't I don't think it's better not your worst fear. 0:22:41.760 --> 0:22:43.399 That is not that bad. That'd be hard. It's a 0:22:43.440 --> 0:22:45.120 lot easier to shut your hand in a car door 0:22:45.160 --> 0:22:48.000 than a window. But O, man, that hurts either way. Yeah, man, 0:22:48.040 --> 0:22:49.560 I had a knock wood. That hasn't happened to me 0:22:49.560 --> 0:22:52.040 in a long time. Yeah. Every time my daughter shuts 0:22:52.080 --> 0:22:53.960 the door, which I tried to let her do whatever 0:22:53.960 --> 0:22:57.080 she can on her own, I'm always just like, don't 0:22:57.080 --> 0:23:01.119 do it. Do you put ovenmits her hands first? No? No, 0:23:01.200 --> 0:23:04.840 nanny stayed at our house. Uh. So you you get 0:23:04.920 --> 0:23:08.080 hurt on your hand, Let's say, Um, the signal that 0:23:08.200 --> 0:23:11.280 is gonna travel it travels through the into the gray 0:23:11.280 --> 0:23:13.560