What Happens to Your Brain When You Are in Pain? – A Look at the Pain Mechanisms Model
- Jess Mcdonald
- Dec 15
- 6 min read
Pain is an essential part of human experience, designed to protect us from harm. But have you ever wondered what happens inside your brain when you’re in pain? Understanding the pain mechanisms model can provide valuable insights into the complex relationship between pain, the brain, and your overall experience.
The Power of the Pain Mechanisms Model
Pain is not just a physical sensation—it's an experience shaped by your body, brain, and the world around you. The Pain Mechanisms Model offers a revolutionary way to understand why we hurt. It moves beyond the idea of pain being tied solely to tissue damage and embraces a more holistic view.
This model acknowledges the role of biological factors, like inflammation and nerve signals, but also recognises the influence of emotions, memories, and even the environment on our pain. By understanding this interplay, we can better explain why pain persists, why it sometimes intensifies without injury, and—most importantly—how to break the cycle.
Whether you're a physiotherapist, a person experiencing pain, or simply curious, the Pain Mechanisms Model empowers us to see pain as a signal we can decode, not a life sentence we must endure. Knowledge is power, and when it comes to pain, understanding is the first step toward relief.
The Pain Alarm System
Pain is not just a signal from the body; it is an experience created by the brain. When you touch a hot surface or sprain your ankle, specialised sensors in your body called nociceptors detect potential danger. These sensors send electrical signals through your nerves to the spinal cord and then up to the brain. This is often referred to as the "alarm system."
However, nociception (danger signals) does not equal pain. Your brain processes these signals and decides whether to create the sensation of pain, based on the context and perceived threat.
The Brain’s Role in Pain
Once danger signals reach your brain, several regions work together to assess the situation:
The Sensory Cortex: Maps out the location and intensity of the pain.
The Limbic System: Processes the emotional and memory-related aspects of the pain.
The Prefrontal Cortex: Helps you make sense of the pain and decide how to respond.
This collaborative effort means that pain is influenced by not just physical injury but also emotions, memories, and beliefs.
Why Pain Is Not “All in Your Head”
While the brain creates pain, it doesn’t mean it’s imaginary. Pain is a real and valid experience, influenced by:
Biological Factors: Tissue damage, inflammation, or nerve sensitisation.
Psychological Factors: Stress, anxiety, and depression.
Social Factors: Support systems, cultural beliefs, and work environments.
The Good News: Your Brain Can Change
The concept of neuroplasticity tells us that the brain is adaptable. With the right strategies, you can retrain your brain to calm the overactive alarm system. Here are some evidence-based approaches:
Movement and Exercise: Gentle, graded movement can help desensitise the nervous system.
Education: Understanding how pain works reduces fear and improves outcomes.
Mindfulness and Relaxation Techniques: These reduce the brain’s perception of threat.
Professional Support: Physiotherapists, psychologists, and pain specialists can guide you through personalised strategies.
A Real Life Example. Imagine This…
During a long, sweltering car ride back to university after celebrating a basketball grand final win, I experienced a type of back pain I’d never felt before. What started as a dull ache turned into shooting pain down my leg, accompanied by muscle spasms. I hadn’t injured myself, and the pain lingered for weeks, unpredictable and frustrating. Doctors referred to it as non-specific lower back pain (NSLBP), meaning the exact cause was unclear.
What Was Really Happening?
Pain isn’t just about damaged tissues—it’s a whole-body experience involving your brain, emotions, and the environment. Let’s break it down:
The Environment Mattered
Imagine driving alone for hours in scorching 40-degree heat. The air conditioning is broken, you’re stuck to sticky car seats, and you’re sleep-deprived after a night out. You’re also feeling stressed about an upcoming exam and replaying a conversation with a relative whose back pain ended their sporting career. All of this created a perfect storm.
My brain was constantly processing these environmental stressors, interpreting them as threats, and amplifying the signals from my back. Context plays a huge role in how pain feels—your surroundings, emotions, and memories all feed into your pain experience.
Body Signals
Think about sitting in one position for too long. Your muscles and joints start to feel stiff, and your body’s sensors—called nociceptors—send signals to your brain about potential danger. Add in inflammation from a hangover and your body becomes hypersensitive. It’s like turning the volume up on your internal alarm system.
In my case, these danger signals weren’t just from physical strain but also from my body’s reaction to dehydration, heat, and stress. Together, they created a cascade of signals that my brain processed as pain.
How It Felt...
Pain doesn’t just exist in your body—it’s a mix of sensations, emotions, and behaviours shaped by your brain’s interpretation of what’s happening.
How I Felt
The pain wasn’t just physical. I felt fear—what if this never goes away? Frustration—why can’t I move like I used to? And uncertainty—what does this mean for my future as an athlete and physiotherapist?
Imagine feeling pain and being bombarded with “what ifs.” That’s how your brain takes over, amplifying the experience.
How I Reacted
Out of fear of making things worse, I moved cautiously. I adjusted my posture constantly, avoided bending, and even exaggerated my pain responses, like groaning or grimacing. While these behaviours felt protective in the moment, they actually reinforced my brain’s belief that something was seriously wrong.
How My Body Responded
My body reacted as if I was under threat. My heart raced, my muscles tensed, and I even felt nauseous. These physiological responses weren’t just about the pain itself—they were my body’s way of trying to protect me.
Why the Pain Stuck Around?
Pain can become a cycle. Your brain keeps revisiting the signals from your body, influenced by your thoughts, emotions, and environment. Imagine having an overly cautious alarm system—it keeps going off, even when there’s no real danger.
In my case, my fear, stress, and lack of sleep kept feeding this loop, making my body more sensitive to even normal movements, like sitting or bending. This is why pain can sometimes feel worse over time, even without further injury.
Why Understanding Pain Helps
Pain is not just about damaged tissues; it’s about how your body and brain work together to keep you safe. While this can make pain feel overwhelming, it also gives you the power to change your experience.
Imagine understanding your pain - Instead of fearing it, you see it as your body’s way of protecting you. You learn that movements aren’t harmful and can actually help.
Imagine retraining your brain - By gradually moving and challenging those pain beliefs, you turn down the volume on that overactive alarm system.
Imagine feeling in control again - Knowing that pain isn’t permanent and that you can influence it gives you the confidence to take proactive steps.
Pain may be complex, but it’s not permanent. By understanding how it works, you can break the cycle and move forward with confidence.
Understanding Your Pain
If you’re living with persistent pain, remember: pain is real, but it’s also something you can influence. By learning about how your body and brain work together, you can take control of your pain experience.
Start by exploring gentle movements that feel safe and manageable.
Consider working with a physiotherapist or healthcare provider who understands modern pain science and can tailor a plan just for you.
Dive into resources that explain the science of pain in easy-to-understand ways—it’s empowering to know what’s happening in your body!
By understanding how the pain mechanisms work, this person could start gentle, graded exercises to retrain their brain and body. A physiotherapist might guide them through movements that gradually increase their confidence without triggering pain. Alongside education about pain and mindfulness strategies to reduce stress, these steps can help recalibrate their nervous system and lessen their pain over time.
Pain is a complex, brain-mediated experience that involves much more than just physical injury. By understanding the mechanisms of pain and how the brain plays a role, you can take proactive steps to manage and reduce it. Remember, your pain is real, and there are ways to change your experience for the better.
