Central Sensitisation: When the Nervous System Becomes Hyper-Reactive

If you’re reading this, chances are something has changed about your pain.

Maybe it started in one place — your lower back, your neck, your pelvis. And then, over time, it began to spread, and the intensity increased. Maybe you find that you can now do even less than when your pain first started?

Maybe light touch now feels uncomfortable, you don’t want a hug from a loved one, you feel like your nerves are ‘twitchy’. Maybe clothing, or your bedding irritates your skin. Maybe you feel exhausted, foggy, or overwhelmed in busy environments. Maybe bright light, movement, noise, texture feels like too much, even when you know it isn’t.

You might have been told, “Your scans look normal, or we can’t find anything wrong with you, or there is nothing serious going on.”

And that can feel confusing — or worse, dismissive – because your pain is worse, and it is not going away regardless of how much medication you take.

At The Pain Collective, we want you to know this:

When pain spreads or becomes more intense, it doesn’t mean it’s imagined. It often means your nervous system has become more sensitive, and is now responding to normal input as if it is dangerous – this is called Central Sensitisation.

And the good news? Sensitive systems can calm down.

What Is Central Sensitisation?

Central sensitisation is a term researchers use to describe a nervous system that has become hyper-reactive. Your nervous system’s job is to protect you. When you sprain an ankle or strain a muscle, nerves send warning signals to your spinal cord and brain that something potentially dangerous is happening in your tissues. That’s helpful — it gets you to rest and recover.

But sometimes, after an injury or period of stress, the system doesn’t switch off properly. Instead, it becomes more alert. More protective. More easily triggered. It starts firing for normal sensations as if they are dangerous. Think of it like a car alarm that keeps going off even when there’s no-one near. The car isn’t in danger, there is no break-in. The alarm has just become too sensitive! Another way of thinking about central sensitisation is like a computer programming software error – the way in which the program understands information coming in has an error, which means that the output is also incorrect.

Research over the past two decades shows that in some people with persistent pain, the spinal cord and brain turn the volume up on incoming signals. Harmless or normal or helpful sensations may start to feel painful. Normal touch or aches may feel intense. Pain may spread beyond the original site and change its character. Other sensations also become more intense, like light, sound or movement, and things become overwhelming more quickly.

This is central sensitisation.

Different Types of Pain — And How They Overlap

Understanding central sensitisation also means understanding that not all pain is the same. There are three types of pain – nociceptive, neuropathic and nociplastic pain. In this blog we will be considering how nociceptive and nociplastic pain influence each other. For more information on neuropathic pain, please read our blog here. 

What is nociceptive pain?

This is pain that is usually caused by actual or ongoing tissue irritation or inflammation.
For example:

• A disc pressing on a nerve
• Inflamed joints
• Sprains or fractures
• Muscle spasm
• Post-surgical inflammation

This type of pain is protective and is typically linked to specific and identifiable body tissues.

Nociplastic Pain

This is pain driven more by changes in how the nervous system processes signals — and there may not be evidence of clear ongoing tissue damage.

This type of pain is closely linked to central sensitisation. Fibromyalgia is a well-known example, but nociplastic pain can occur in many conditions, and essentially means that the system has become too sensitive. The important part to remember is that in real life, pain rarely fits neatly into one category.

It is entirely possible for pain to start with a clear nociceptive trigger — an injury, inflammation, surgery — and for the nervous system to become sensitised over time. Now both mechanisms are contributing:

• The body might still be sending some warning signals.
• The nervous system turns the volume up on those signals.
• The brain interprets more threat than is truly present.

This overlap is common in long-standing back pain, pelvic pain, migraine, and post-surgical pain, and can be caused and maintained by many different factors.

So when we talk about “treating the nervous system,” we are not ignoring the body.
We are recognising that both layers may need attention.

Why Scans May Look “Normal”

Many people with central sensitisation are told their MRI or blood tests don’t explain their pain. That’s because the issue isn’t always ongoing major tissue or structural damage. It’s the sensitivity of the system interpreting signals.

Over the last 20 years, research has demonstrated that pain is often not a direct measure of injury or the amount of tissue damage, but rather a protective output from the brain, based on how threatened it perceives you to be, how much danger it thinks you are in. When the system is sensitised, the brain may overestimate danger and turn the volume up on pain, fatigue, anxiety and sensory information. Understanding this can be both confronting and relieving.

Confronting — because it means pain isn’t always solved with one single fix.
Relieving — because it means nothing is “seriously wrong.” Your system is just stuck in protection mode.

Addressing Both Layers of Pain

When nociceptive and nociplastic pain overlap, treatment often works best when both are addressed.

Step 1: Reduce Ongoing Nociceptive Drivers

If there is a persistent inflammatory or mechanical contributor, calming that can reduce the overall threat load.

This may involve:

• Targeted physiotherapy
• Anti-inflammatory strategies
• Hormonal treatment (in conditions like endometriosis)
• Optimising posture and biomechanics

In some cases, carefully selected minimally invasive neuromodulatory procedures such as pulsed radiofrequency can temporarily reduce specific danger signals reducing the overall load or ‘noise’ in the system.

These procedures are designed to calm overactive nerve pathways or interrupt persistent nerve impulse transmission from a particular region of the body. When used appropriately, they don’t “cure” central sensitisation — but they can:

• Reduce pain intensity
• Lower background irritability
• Create a window of opportunity

And that window matters. It is a means to an end – to allow people to engage in active, self-management strategies for long term health.

When pain reduces even partially, people can:

• Move more confidently
• Sleep better
• Engage in graded exercise
• Participate in psychological therapies
• Rebuild daily function

In other words, by turning down nociceptive input, we often make it easier to address the nervous system’s sensitivity.

Step 2: Calm the Sensitive Nervous System

Once the overall threat level reduces, we focus on nociplastic contributors.

Research supports a biopsychosocial, supported self-management  approach for centrally sensitised pain. That means addressing biological, psychological, and lifestyle factors together.

1. Education: Understanding Reduces Threat

Learning how pain works changes brain activity.

When people understand that pain does not always equal damage, threat levels decrease. Studies show that pain education can reduce fear, improve movement, and lower reported pain levels. Understanding your nervous system is the first step in calming it!

2. Graded Movement: Rebuilding Confidence

Avoiding movement is a completely understandable response when everything hurts. But avoiding movement long-term can reinforce the brain’s message that activity is dangerous. It also leads to stiffness and muscle weakness, which then adds some nociceptive triggers to the mix. The right amount of gentle movement is one of the best treatments we have for central sensitisation pain. The trick is to use gradual exposure to movement you enjoy — starting small and building slowly.

The goal isn’t to push through pain. It’s to teach the nervous system that safe movement is not a threat. Over time, the volume knob turns down and the brain no longer has a meltdown when you move normally.

3. Sleep and Stress Regulation

Poor sleep and chronic stress amplify central sensitisation.

Supporting sleep hygiene, breathing practices, structured pacing, and stress management reduces background sensitivity and reduces nervous system overwhelm.

Every small change adds up.

4. Psychological Therapies

Approaches such as Cognitive Behavioural Therapy (CBT) and Acceptance and Commitment Therapy (ACT) are strongly supported in research for centrally sensitised pain.

Engaging in these therapies doesn’t mean your pain is in your head or purely psychological – it recognises that we cannot separate emotional and physical health from each other.

These specific therapies have been proven to help reduce the brain’s perception of threat.

When fear reduces, the volume gets turned down.

5. Medication (When Appropriate)

Certain medications can calm overactive nerve pathways. These are different from standard anti-inflammatory drugs and are sometimes used specifically to reduce central amplification.

Medication alone is rarely the full answer. But in combination with movement and education, it can be helpful.

What About Flare-Ups?

Flare-ups are common when nociceptive and nociplastic pain overlap.

They don’t mean you (or the treatments you tried) have failed. They usually mean something has changed that the system perceived as an increased threat — from stress, poor sleep, poor diet, dehydration, illness, work pressure or just life-overload.

Dealing with a flare-up doesn’t mean shutting down completely and giving up on everything – it means working with your team to work out what has changed, adjust gently, take courage and continue forward.

Can Central Sensitisation Improve?

The short answer is yes. Your nervous system learned to become sensitive - it can learn to become more balanced again.

Brain imaging studies show changes in pain-processing networks after education, graded movement, and psychological therapies. Clinical studies show improved  function and reduced pain intensity with multidisciplinary care. Sometimes that journey includes calming peripheral drivers first and sometimes it means directly retraining the brain and spinal cord.

Often, it means both. The journey looks different for different people, but the important message is that sensitive systems can learn to become less sensitive.

Final Thoughts

When pain spreads, becomes unpredictable, or feels disproportionate, it can be frightening. If you think you might have central sensitisation, be assured, it doesn’t have to be a life sentence.

It is merely a state of heightened protection. Your brain is doing what it does best – protecting you from harm! And while being overprotective isn’t necessarily useful, if your brain can learn to become too protective, it can also learn to be less protective. The system can be recalibrated.

This is why treating persistent pain often means treating both the tissues and the nervous system’s sensitivity.  When we reduce ongoing nociceptive input and support the nervous system to feel safe again, meaningful recovery becomes possible.