# Our Danger Alarm System ##### Untangling Pain ---  --- ## tl;dr **Alarm system overview** - Our body has a sophisticated alarm system with nociceptors (fire alarms), spinal cord (child), and brain (parent) - This is a simplified model I use for clients - Not perfect, but a great starting point **Nociceptors: fire alarms** - Nociceptors are sensors constantly surveying for danger - No such thing as pain sensors - pain is produced *by* the brain - Nociceptors respond to danger, *not* pain **What sets them off?** - Tension and pressure (injuries, poor posture) - Temperature (heat, burns) - Chemicals (poison, wasp sting) - Hormones (stress, menstrual cycle) - Nociception happens constantly to protect us **Spinal cord: the amplifier** - Spinal cord gets danger messages, *not* pain messages - Acts like a child: can scream to the parent (amplify), or calm down (reduce) **Brain: the decision maker** - Brain decides whether to produce pain based on many factors: emotions, beliefs, past experiences - Pain is just one of many responses to perceived danger **Real vs. perceived danger** - Brain can produce pain even if there’s no real danger - Can also suppress pain when danger *is* real - Example: no pain when shot or bitten by a shark - Example: Lorimer Moseley’s snakebite and later pain from a stick **Nociception is good** - It protects us - Chronic pain happens when the system becomes overly sensitive --- ## Transcript Our body is fitted with a highly sophisticated alarm system, which helps to protect our body. So this system includes a number of parts that work together. Including nociceptors, or the fire alarm. The spinal cord, or in this case the child. And the brain, which in this case is the parent. So we're going to look at each one in a little bit more detail and how they fit together. This is my simplification of this danger alarm system. It's been developed over years and I've been trying to piece things together and understand things and make it in a way that I could explain to my clients. And this is the description and explanation I've used for my clients and it's worked brilliantly. They've loved this idea. It is a simplification. So if you are a pain scientist, I apologise. Please do not shoot me. I appreciate that it's so much more complex than this. And this is not perfect, but I had to start somewhere. So, nociceptors. We're gonna look at this alarm system, and we're gonna start off with the nociceptors. Nociceptors are the fire alarms. All around our body, there are millions of sensors. And again, these are called nociceptors. And, if you don't want to remember that word, nociceptors, just remember fire alarm. Makes it easy. So, we've got lots of fire alarms around our body. And they are constantly surveying their area for activity. Now, before we go any further, as a side note, we do not have pain sensors, okay? I still read books that talk about pain sensors, as if we're sensing pain somehow. So if something happens, we've got pain, and we're sensing the pain. That is not what happens. We do not have pain sensors. We do not have pain receptors. We do not have pain nerves. Despite what so many books say. Pain is produced by the brain. Pain is produced by the brain. That is one thing you need to remember. So, again, we can think of nociceptors like fire alarms. They're highly sophisticated fire alarms that actually respond to a number of different stimuli. So they're looking for danger. Nociception basically means danger reception. And there are a lot of different types, but I'm just putting them into one type at the moment. They're just fire alarms. So, they are looking for danger. And they can look for danger in lots of different stimuli. They're looking for tension and pressure. If we go over on our ankle, it increases the tension of the muscles and the ligaments, which can set off the fire alarms, these nociceptors. Or with regards to tension and pressure, we might be sitting for too long at our desk. And this can increase the pressure in our muscles, and it can set the fire alarm off. Because we've been sitting for too long and our body goes, ooh, this is a danger, let's set the fire alarm off. So that's one way. The next one is temperature. When we stand too close to the fire, warm our butt on the fire and it gets a bit too hot. The fire alarm can go off. Or we might spill hot macaroni cheese on our foot. Which may just be me, but, that's another one that the fire alarms are set off. Moving on to chemicals, such as ingesting poison. Or being stung by a wasp, again, fire alarms are set off. Or hormones, such as being overly stressed. Which results in the body releasing hormones. Or also during perimenopause or certain times of the menstrual cycle, we can have too much of certain hormones, and again, this can set the fire alarm off. It's important to know that the fire alarms are constantly being set off. All the time. This is because nociception is happening all of the time within our bodies. The body's constantly surveying what's going on. And that's a good thing. These nociceptors, they're here to protect us. But a bit like a real fire alarm, which does not tell you, the difference between the house being on fire, or burnt toast. These sensors do not give you any more information other than, "Hey, there's a potential issue down here. You might wanna do something about it." So that's what the fire alarms do. They are just sensing around, sensing for danger. If they sense any danger, the fire alarm will be set off and we will get a message. When activated by enough unpleasant stimuli, the sensors, the fire alarms, send a message to the spinal cord, letting it know that something is not quite right. So they're letting the spinal cord know that there's a potential threat to the body. Again, it's important to know, that the message that is sent to your spinal cord, via the nerve, only says danger. It doesn't say pain. It does not say pain. It says danger. The job of the spinal cord is to act as an amplifier. So it can turn up the alarm, where the message then gets passed to the brain. Or it can turn down the alarm where less of the message gets passed on. If we go back to the fire alarm analogy, the fire alarm, nociceptor, detects a danger and it sets off an alarm sound. This alarm is then heard by the child, in this case, or the spinal cord, who's watching TV in the front room. Now, either the child, spinal cord, runs around screaming up the stairs to her parent, which is the brain, telling them that something bad is happening. So she's amplifying the danger message. Or they might grab a towel, clear the area around the fire alarm, and go back to watching the TV. So reducing the danger message. Obviously, as in real life, if the information is passed on, so if the child screams up the stairs, that something dangerous is happening, then this doesn't necessarily mean that the parent will do anything about it. So first, the parent has to interpret the message, and the same is true for the body as well. If the alarm is set off, and is then amplified by the spinal cord, this does not necessarily lead straight to pain. First, it has to be interpreted by the brain, or in this case, the parent. When a message has been passed on from the spinal cord to the brain that there's something wrong, it is then up to our brain to make a decision about what the information means and what needs to be done about it, if anything. So ultimately, it's the brain that makes all the decisions about what to do with the information given. But it doesn't just do that based on that one single message. That one danger message. It decides what it should do based on so many different factors. Again, this is what we refer to as, as multifactorial. We are looking at emotions, past experiences, beliefs, attitudes, expectations. These all play a part in whether or not pain is produced. And how much pain we experience as well. Back to the firearm analogy. An unpleasant stimuli sets off the fire alarm. Nociceptors. The child, the spinal cord, hears the alarm. Runs around screaming that something bad is happening. The parent, hearing the child, knows that like all information we receive, some of it is useful and some of it is not. And so they take in all the different factors and make a decision about what the screaming child and the fire alarm actually means. And what needs to be done about it, if anything. So this is where, on the image, the brain, the parents thinking, well, so the fire alarm's gone off, the child's screaming, so either, maybe the house is on fire. Or it's burnt toast. So, if the brain believes that the body is in danger, based on all the information gathered, then it will send a message to the body to do something about it. So, if the brain thinks the house is on fire, then it can create a number of different reactions. So the body might create muscle tightness. It might create this release of chemicals, or this inflammatory response. There can be a stress reaction as well. Or, as you probably guessed it, the body might actually produce pain. So pain is very similar to those other responses. In other words, if the parent believes that the house is on fire, based on all the information gathered, then they will call the fire brigade. Or, in this case, if the brain believes that the body is in danger based on all the information gathered, then it will produce pain. But, remember that it's the brain that decides what the information means and what to do about it. If the brain or the parent believes that the fire alarm is going off, simply because the toast is burning, even if the house is on fire, then they will calm the child. And turn off the fire alarm. They will not call the fire brigade and, if we go back to the actual real thing, if the brain believes that the nociceptor is going off simply because it's been switched on for whatever reason, and the spinal cord has amplified this message, but the brain thinks, actually, do you know what, we're not in danger. It's not going to produce pain. Even when something dangerous is happening. There's been loads of different cases with these. Especially like during the war and stuff when people are shot. They can be shot. And their muscles are damaged. A fire alarm goes off, this sends a message to the spinal cord. The brain then goes, okay, yes, I appreciate that we have been shot, but right now, pain is not the best thing to do about this. So let's just not produce pain. Because if we produce pain, then we're going to shut down, aren't we? Whereas if we don't produce pain, we can then carry on as normal. I've read other cases of a guy having been attacked by a shark. And I think he lost a leg. And at the time he felt no pain whatsoever. No pain whatsoever. But again there was damage. Massive amounts of damage. But no pain, because the brain decided that it wasn't going to produce pain. That it was not a sensible time to produce pain. So this is what can happen. We can also look at this another way as well. Remember me saying at the beginning that pain is associated with real or perceived potential tissue damage. This is the perceived part. Sometimes, something trivial may set off the fire alarm. This sends a message to the spinal cord, who panics. And then sends the message to the brain. And sometimes the brain can perceive this as something terrible happening. Or that something terrible is going to happen. Based on past experiences, on attitudes, on beliefs, so many different factors. And it can produce pain as a result. Now one of the things I've read in this instance, Lorimer Moseley, he was one of the guys that wrote Explain Pain. He was saying that he was walking in the Australian bush, and he got bit by a snake. Obviously he got quite poorly from this. But what happened is a lot, lot later on, after he was healed and recovered and everything else. He was walking again, and he instantly got this pain, and he fell to the ground. His brain thought that he was being bitten by a snake again. And actually it wasn't. He'd been grazed by a stick. But his brain perceived it to be something terrible. And so produced this massive amount of pain, because that would get him out of this perceived danger. And that's what can happen. Sometimes, something terrible is not happening, but our brain perceives it is. So it can be something little, and our brain goes, oh my god, this is really, really terrible, and the child's screaming, and the parent's screaming, and the alarm's going off, and this is what happens. And this is why the pain can be way more than the actual event. With all that, I want you to remember that nociception is a good thing. Although it doesn't sound like it. Nociception is a good thing. Because the whole point of our danger alarm system, is to protect us. The only problem is that sometimes the system can become a bit faulty and overly sensitive. Which is what happens with chronic pain. But again, please remember that nociception is a really, really good thing. --- Next lesson → [[Untangling Pain – Module 1 Lesson 04|next lesson]] %% ==Lorimer Moseley’s story of snakebite and mistaken pain response== - [[Our body is fitted with a highly sophisticated danger alarm system, which helps to protect our body]] - [[Nociceptors are like fire alarms]] - [[types of danger detected through nociception]] - [[we have constant Nociception going on within our bodies]] - [[When activated by enough unpleasant stimuli, the nociceptors send a message to the spinal cord]] - [[the spinal Cord is like a Child hearing a fire alarm]] - [[the brain is like a Parent and interprets danger itself]] - [[If brain believes the body is in danger, it sends a message to the body to create different reactions]] - [[the brain decides what to do about the fire alarm]] - [[Lorimer Moseley Example of pain – getting bitten by snake]] - [[Nociception is a good thing]]