The neuroscience behind pain

Hi all, my name is Kim Clayden, and I am a solution focused psychotherapist and clinical hypnotherapist. I specialise in working with client’s who have pain and long-term health conditions and help with a wide variety of mental health issues too. In this article, we will be going into the neuroscience behind pain and what we can do in terms of positive self-management and living well with a hypermobility syndrome. I was diagnosed with hypermobility Ehlers Danlos syndrome (hEDS), fibromyalgia, myalgic encephalomyelitis (ME), and postural orthostatic tachycardia syndrome (PoTs) many moons ago, so I will bring a lot of lived experience to this article as well as the neuroscience for you.

We will start with pain.

We have two main types of pain. Acute pain is the type of pain that most people will have experienced at some point in their life. Whether you fell over, fell off a swing as a kid, maybe you have broken a bone, tore a ligament, burnt yourself on the oven, got an infection in a wound etc. You and I know, this heals and goes away and then we carry on with life as normal. They are a temporary nuisance if you will.

Acute Pain is basically a warning of harm to the body, either as a result of internal disease processes within the body or damage caused by an accident. It is part of the fight and flight reaction to ensure further harm is minimised. When you are initially injured, your body will release adrenaline and stress hormones to give you what you need to get out of immediate danger.

Chronic pain is a more complex problem. Although it is defined as a ‘persistent pain’ that occurs for more than X amount of time, we as hypermobile folk, can hit a grey area. Chronic pain is also defined as having a ‘no injury site’ and yet, they can have – hence the grey area. More detail on this later. For now…

Primary chronic pain, unlike acute pain, serves no immediate biological purpose, even though it can affect the whole of the patient’s life. Often it will become part of the ‘opt-out’ clause associated with clinical depression and anxiety. It is when pain persists after an injury for 3 or more months and there is no longer an ‘injury or pain’ site anymore.

It does, however, have an evolutionary purpose to ensure our survival and I think it is important for all to understand where this signal comes from as it can change your perspective on it. Let me explain… Back in the ‘caveman’ days, if we were to injure ourselves, we would have to worry about something deciding if we are tasty and would need to hide pretty quickly. The acute pain will be there from the initial injury, causing a wide range of reactions to start to take place inside your body, such as adrenaline being released so we can get our butts out of danger even with the injury, it reduces the pain in the short term, cortisol starts shutting down unnecessary systems, so everything can be focused on your survival.

OK - We are safe! In the cave, tucked away with a warm fire, now we need to heal. This is where the chronic pain signal comes into its own element. Our body and our brain are telling us now we need to stop, rest, and keep safe until we are fully healed from the initial injury. We now have the pain gates open in our brain, which is located in the dorsal horn of the spinal cord, the acute pain is now healed but there is still pain there, why?

Unfortunately for us, our brains are quite lazy. If you are receiving a pain signal and there is no site of injury, your lovely, amazing brain has simply forgotten to switch it off! So, we are still getting the pain signals, and this causes us to brace the area, then we ache from all the bracing/tensing, this causes inflammation in the area, muscles tense, and so the pain signal keeps on looping! This chronic pain has unfortunately become a habitual signal in which our brain has simply forgotten about as it is so busy doing other important stuff, ensuring your surviving.

The reason why hypermobility is a grey area is because those with hypermobility syndromes can be having a constant strain of micro and macro traumas (acute trauma), so a lot of us may be dealing with a constant strain of injuries on top of the ‘chronic pain’. This leaves our pain gate open and makes us even more susceptible to primary chronic pain AND secondary chronic pain, they can coexist. Secondary chronic pain is where we have persistent pain, but it is from an underlying condition which accounts for the pain, like osteoarthritis and inflammatory bowel diseases (IBD’s) too, it can come from the bones, joints, muscles, spine, and related soft tissues. This category of pain is a fairly recent one, and I truly think that is where we belong. Whichever category you fall into, your pain is valid and a real pain signal, injury or no injury, it causes suffering.

A lot of people with chronic pain are seen to be in a category of ‘overachiever’ (myself included). They will have probably been running on adrenaline for a long time and have excess cortisol in their system. Cortisol causes a wide range of things to happen and if we are exposed to it for a long period of time, it isn’t healthy.

Cortisol plays a role in:

• Controlling blood sugar levels

• Regulating the body’s wake sleep cycles

• Managing how the body utilises carbs, fats, and proteins

• Causing inflammation

• Increasing blood pressure

Another thing to remember with the ‘overachiever’ is that they probably will have a multitude of symptoms on top of their pain. They would have been pushing through, and their brain will have been trying to get them to stop! It can cause gut issues such as irritable bowel syndrome (IBS), headaches, and migraines. The brain will be trying to come up with ways of making the person stop and rest.

Well, they aren’t stopping, and they are in pain, so let’s make it worse. OK, they are still not stopping, let's make them need the loo a lot so they stay at home and rest. Urgh, STILL NOT LISTENING! Migraines! Panic attacks! The list can go on. Until they cannot cope anymore, and it hits them like a tonne of bricks. Sound familiar? It does for me.

Simply put: Pain is a sensation which is felt when nociceptors are stimulated. A nociceptor is a sensory receptor for painful stimuli. Nociceptors send the pain sensation to the spinal cord through nerve fibres, which is the threadlike extension of a nerve cell.

Subsequent transmission to the brain is via A-Fibres (fast pain), short, sharp, and well localised (this fast pain is often referred to as ‘acute’) or via C-Fibres (slow pain), burning, aching, and poorly localised (this slow pain is often referred to as ‘chronic’).

A-fibres are fast transmitters and take precedence over C-Fibres. Therefore, if there is chronic pain and a new injury is sustained, the new injury will take priority and block the old C-Fibre message.

The fastest A-Fibre of all, is a specialised fibre which we call an A+ fibre that transmits sensations of pressure, touch, and vibration. Therefore, rubbing or massaging the area of pain can stop the acute pain, in effect it provides competing counter stimulations, or distraction, that can block the pain from registering or even reaching, the brain.

So, we can only receive one pain signal at a time. A TENS machine works on patients with chronic pain in a similar way as rubbing the painful area. A TENS machine bombards the brain with loads of A+ fibres and because they are a faster fibre than the C-fibre, they take precedence over that chronic pain signal.

These A-Fibres and C-Fibres carry the pain ‘message’ to the thalamus, which is your relay station in the brain, all motor and sensory signals come through here except for smell. Fibres from the thalamus project to the primitive, emotional brain, in particular the amygdala, which explains the emotional aspect of pain manifestation. C-fibres constantly ‘wake-up’ the amygdala, the poor amygdala is basically being constantly poked like a bear that’s trying to hibernate for the winter. Imagine a bear trying to hibernate for winter and someone is sitting there constantly poking it with a stick each time it just starts to drift off. This is going to make the polar bear feel miserable, angry, emotional, and their stress bucket fills up in no time!

This causes us to not be able to think logically, we cannot reach that intellectual area of the brain because our stress buckets are so full all the time. From my experience with myself and my clients, we couldn’t see a way out of this situation either when we were there. A lot of people may explain that their brains feel foggy, they can’t think straight, and this is usually the reason why. The language centre is in the upper brain and if we are constantly working in that primitive, emotional area, we struggle to get access to the language centre, causing us to forget words and get frustrated when we can’t think of things etc.

Another way of looking at and understanding the different fibres is with the motorway analogy.

In the left lane, the slow lane we have our lorry trundling along at a steady pace but slightly under the speed limit. This is our C-fibre signal (chronic).

In the middle lane we have the family car, it is a bit faster than the lorries, over taking them steadily. This is our A-fibre signal (acute).

In the fast lane we have our speedy sports cars, the Audis/Mercs, these are our specialist A-fibres (A+), which are the fastest! We want to utilise this for our benefit as much as possible. Alongside being the fastest, we can only receive one pain signal at a time, which means if you were to break a bone, this would override the chronic pain signal you experience, because chronic pain is slower. Acute and A+ are both faster than the primary chronic pain and take precedence over the chronic.

A+ fibres are your best friend for managing your pain and giving yourself a break from suffering! Have a little think about what you currently use and have in your home that can create that lovely distraction sensation.

Have a think about what things can help distract your brain away from pain? What things could work together? This is because as soon as we lay down for bed, in the silence of the night and just with our thoughts, all our brain can focus on is the pain which can amplify it for us. So, what else can help at night or during the day to distract your focus from pain?

By using things such as TENS machines, TENS pens, hot water bottles, heat packs, ice, massage, and compression gear. Also, adding more distraction for the brain such as music, TV, audio books, perhaps doing something with your hands too like crochet, knitting, painting, drawing, and colouring is perfect. They may need to be adapted to help with pain. Other very useful activities that are helpful are deep breathing, deep muscle relaxation, hypnotherapy, walking, gentle stretching, talking, writing, puzzles, and gaming.

Through these resources, you can start to create your own handy box of stuff. Your toolkit, if you will, of ‘things’ to enable you to live happier lives. They can be physical things like splints and bracing to reduce pain but also pain distraction things too.

Central Sensitisation

Now, when it comes to stress and central sensitisation (that’s the spinal cord and brain), different approaches such as cognitive behavioural therapy are recommended within the NHS, however, hypnotherapy and deep breathing exercises are now being explored more and more, as well as serotonin reuptake inhibitors.

Hypnotherapy and deep breathing are now being explored to reduce stress and anxiety so that the perception of pain at the level of the brain is less intense and these descending inhibitory pathways (which suppresses pain), are more active to try and control this pain.

Getting a good night's sleep makes all the difference in the world, whether you use my night-time recording already to help or something else, but this along with a good bedtime routine (known as sleep hygiene) helps to promote sleep. We are the only mammal that will resist falling asleep! Binge watching Netflix etc lol, so please if you feel sleepy, go with it.

A better understanding of the gut / brain link for you

For a lot of these folk, they will have an increased sensitisation of the gut and pain receptors. As I mentioned previously, we can have a lot of inflammation in our blood because of previous injury, infections causing stress on the body etc. This then can cause a state of central sensitisation, which is the nerves in the spinal cord becoming heightened and much more sensitive to pain signals. So, the gut itself can cause the heightened sense of pain to the spinal cord and brain, if it has been infected, injured, or inflamed.

So, what is happening here is that the gut sends very heightened signals off to the spinal cord nerves from the peripheral nerves in the gut (peripheral nerves are the nerves that reside outside your brain and spinal cord). These spinal cord nerves, sometimes, if the intensity of the sensation coming from the gut is very strong, get sensitised at the level of the spinal cord. This is described as central sensitisation, which basically means that this signal from the gut is strong enough that it can cause the spinal cord signal to be amplified, which is then further amplified and a stronger signal goes to the brain, and you then perceive that as pain. Everything then, gut and brain, heightens all the pain signals.

The interesting thing is that once this central sensitisation has started, then this can last for a very long time, even when that gut inflammation or injury is gone. This is useful information for those folk who have gastroparesis, IBD’s such as Crohn’s etc alongside their hypermobility syndrome.

We do know that if there has been a lot of psychological stress, anxiety, stress bucket full etc, then the signals coming from the gut can get amplified, as well as the signals from the brain to the spinal cord, which are normally inhibitory or slowed down. You get less of that inhibition or slow signals, so that this pain gate at the level of the spinal cord is then more open and you get more pain signals going up, so altogether the result of that is that the gut becomes very sensitive, and this seems to be very common in hypermobility syndromes.

The 3 P’s for self-management

Serotonin is a beautiful neurotransmitter that plays a role in pain modulation as well as regulating our mood and aiding in sleep. For us to release serotonin in a healthy amount to aid us in living well with these conditions, we have to utilise the 3 positive parameters of self-management.

Positive Activities - Moving more. I am not asking you to go out and start running a marathon, moving more to you might be, ensuring you do your physio every day, gentle stretching, Pilates, swimming, anything that is low to non-impact on your bodies is best. Moving grows new brain cells, burns away the stress chemicals, and creates new ones. A bit like a personal trainer. So, anything they can do, even a little more than their current ‘normal’ is important.

Think about the sort of positive activities you can do at home. In particular, distraction techniques. Occupying your brain with stuff it likes/loves to do so the brain gets distracted from pain. This is particularly important for those clients that get ‘pain flare-ups’. Pain flare ups can happen with a lot of conditions like fibro, lupus, and hypermobility syndromes, distraction here is key to reduce suffering.

These positive activities can include gaming, reading, puzzles, hot baths, relaxation, meditation, crochet, knitting, colouring, drawing and so much more.

Positive Interactions - Positive online support groups such as those at the Hypermobility Syndromes Association are a good option, also video chats with friends and families is wonderful for our brains, if you aren’t comfortable meeting up face to face yet.

Positive thoughts - We know this can take time. Just try to be a little bit more mindful of the language to start with, it really helps. We know that we absolutely hypnotise ourselves and add to our own stress buckets with the way that we talk to ourselves internally. I remind my clients of this and how they can learn to be a bit more mindful of this, it really does help kick start the process. They may catch themselves saying I ‘can’t do or shouldn’t do X, Y, and Z’. Well, why can’t or shouldn’t they?

This is just a snippet of what goes on in your brain when you are in pain, and I hope you have found it useful to have a better understanding.