🧠 Why People With Persistent Pain Should Care About Predictive Processing
- Edward Walsh
- Sep 10
- 4 min read
If you live with persistent pain, you might wonder: why bother learning about complex brain science like predictive processing?
The answer: because better understanding could literally change how much pain you feel.
🤷 Fine. What is Predictive Processing?
Predictive processing (PP), also known as predictive coding, is one of the most influential neuroscience frameworks. It suggests the brain is fundamentally a prediction machine. It continuously generates predictions about incoming sensory input and then updates those predictions based on the mismatch between expectation and reality (prediction errors).
In school I was taught that our body collects information from the environment through our senses, the brain processes the information and the result is the ordinary conscious experience we are all very familiar with.
In the last few decades neuroscientists have been calling out my biology teacher as a liar liar pants on fire. It turns out rather than information just going:
environment -> brain
It also goes:
brain -> environment
We actively sculpt our conscious experience of how the world is.
💨 Why doesn't the brain just objectively take in sense data?
The brain has to take its best guess because sensory information is ambiguous, meaning the brain has to fill in the gaps. It makes its best guess about what is causing the sensory information.
The brain also prioritises being "safe and fast" over being "objective and slow." There is too much sense data to objectively process all of it quickly; being slow to recognise a predator in the bushes meant being less likely to survive and pass on your objective, slow brain to your children.
On top of that, best guessing uses much less energy than actually sensing. Your brain takes up about 2% of your bodyweight but uses about 20% of your energy. You would need to eat an awful lot of Haribo to have the energy to continually scan the environment from scratch.
🗯️ Cool. How Does This Help My Pain?
Getting there.
PP tells us the brain uses Bayesian inference, a method of combining expectations with new evidence (sensory information), to make the best guess under uncertainty.
This means prior beliefs and expectations shape perception.
You can see this in the image below. The blue line represents prior expectations, the green line represents what one senses in the moment and the red line represents what we consciously experience - our brain's best guess.
In a, the prior expectations (blue) are weak and vague but the sensory observation (green) is clear and strong, so the conscious experience (red line) is pulled more towards what is sensed in the moment.
In b, the prior expectations (blue) are stronger but the sensory observation (green) is still strong enough to shift conscious experience (red line) a little.
In c, the prior expectations (blue) are so strong that the weak, vague sensory observation (green) barely has any impact on the conscious experience.
This can be an unfortunate trap in persistent pain when, for example, the expectation a type of movement will be painful is very strong (understandable when it has been for years). It means even if the sensory feel of the movement has changed, the conscious experience is still of pain because of the strong expectation of pain before the movement - "I know this will hurt". The expectation becomes a self fulfilling prophecy.
In plain English: if your brain strongly expects pain, it can override signals from your senses that suggest no pain.
Example c can also result in less pain. After explaining PP to Llywelyn during his rehab, he nodded and told me about his experience of having an injection with a crafty healthcare practitioner. The practitioner put the needle in without telling them, whilst he was distracted by the conversation. He experienced no pain. The brain prediction that the arm was intact was stronger than the sensory scratch from the needle, so no pain was experienced.
🧠 Great Expectations - How to Retrain Your Predictive Brain
If symptoms are a prediction, it means we can give the brain new evidence to help it make better, more accurate predictions. This is not about mind-over-matter; it's about systematically retraining a biological process.
📖 Educate Yourself: Understanding that pain is a brain output, not just a body input, is profoundly empowering. Awareness is the first step to changing your relationship with the symptom.
🧘 Practice Mindfulness: Mindfulness increases the brain’s attention to raw sensory input. Instead of reacting with fear to a sensation, get curious. Ask yourself: "What does this actually feel like? Is it sharp, dull, warm, buzzing?" This shifts your brain from a simple, fear-based category ("this is dangerous") to more detailed sensory processing in the present moment, which reduces the influence of old, unhelpful expectations.
👉 The Best Way to Start a Mindfulness Practice (+Which mindfulness app is best) 👈
🤸 Embrace Graded Movement: Slowly and safely reintroduce movements that you fear. This provides the brain with powerful new evidence that movement is safe, updating its faulty predictions. This is when consulting a physiotherapist to guide you on which movements, to do when, in what order, can be very helpful.
🏞️ Change the Context: Pain and other symptoms can become linked to certain places, times, activities or people. By changing your environment you can help the brain build new, positive predictions associated with your body.
Writing a New Story
The science of predictive coding doesn't suggest that symptoms are "all in your head." It shows they are a real, tangible output of the brain's prediction process, a process that is fundamentally biological. Symptoms are deeply embodied experiences.
This new understanding offers incredible hope. It offers a road to recovery for those fortunate enough not to have severe issues in the tissues, even when pain has gone on for years.
Because the brain is constantly updating its predictions based on new evidence, we have the power to influence that process. By changing our focus, our beliefs, our behaviors and our expectations we can help our brain write a new, more accurate, less painful story about our body.
References
Van den Bergh, O., Witthöft, M., Petersen, S., & Brown, R. J. (2017). Symptoms and the body: Taking the inferential leap. Neuroscience and biobehavioral reviews, 74(Pt A), 185–203. https://doi.org/10.1016/j.neubiorev.2017.01.015
The Predictive Brain: Rethinking Perception, Emotion, and Dreams with Anil Seth - https://youtu.be/nQdq8wDVUEU?si=9eiYVAVcftt6_YIw
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