What Is Pain and Why Do We Experience It?

By Dr. Ellie Somers

When it comes to knowing pain, the science is clear:1-7

Knowledge is power.

The more I learn about this incredibly complex topic, the more empowered and excited I am about my own body and that of all humans. One of the most rewarding things that I get to do is share information about how impressively smart our body is. This stems from my deep love of science, the body, and the human condition.

My hope is to instill this sense of empowerment and excitement that comes with understanding your body and its response to threatening experiences.

What Is Pain?

To funnel the word pain into a single definition would be like attempting to describe love. It’s entirely too complex for a singular definition and the experience of pain is unique to each of us. There are, however, crucial pieces of information to understand when it comes to “knowing pain.”

First of all, we all experience pain. Pain is normal — unless you have a congenital insensitivity to pain. Without pain, our species would have a very hard time existing in this world.

When working to define pain, it’s important to look to credible sources, rooted in science. Pain has been defined by the International Association for the Study of Pain as “a distressing experience associated with actual or potential tissue damage with sensory, emotional, cognitive, and social components”.8

All of what makes us human and unique intricately influences the way we experience pain.6-7,9-11 We must recognize the biological processes involved, along with the rest of our human condition, which includes the emotional, cognitive, and social processes. This framework is referred to as the biopsychosocial model and encompasses the whole person.6-7,11-12,16

As a person who works with those in pain every day, creating awareness of how a person’s entire life affects why they experience pain when they do is a constant pursuit. But this is a very important first step towards understanding pain.

Our whole self and all of our experiences affect why we feel painful sensations when we do.

Let me repeat this with bold letters because it’s true: all pain is influenced by all of our systems. For example, one might have heightened painful sensations right before a big event because of the complex nature that stress can add to our protective pain system. This may have absolutely nothing to do with the structure of our body, our capabilities, or tissue damage, but more to do with how our body works to perceive the level of threat involved. If a threat is high enough, our system will respond accordingly.

Pain and Bio-Plasticity

What is exciting about us as living beings is that each of us possesses an incredible gift: we are amazing learners. In pain science, this is referred to as bio-plasticity.13 Bio-plasticity is the ability to adapt, learn and change of all of our body’s organisms, based on our experiences, our thoughts, our feelings, our beliefs, how we move, how we speak, what we know, and more.7,12,13

Let’s take strength training for example: adding consistent load to our musculoskeletal system will inevitably lead to change. Our muscles will start to become more developed, our bones will become stronger, and our minds might become more empowered and confident.14 In all, our bodies will adapt as a result of the plasticity, or ability to be changed, of our systems.

This means that our brain is not the only thing in our body capable of learning: our whole body has the capacity to change and learn. When it comes to why we experience pain, the learning that has occurred throughout our entire life’s experience will have its influence.

If our entire body and all of its systems determine that a situation is threatening and that we need to be protected, it might increase our sensitivity to that threat. Turning up our protective dial is a way for our body to keep us safe.

What is even cooler is that pain is only one of our many protective systems that can be turned up or turned down based on a perceived or credible threat. Some other protective systems include our motor system, our sympathetic nervous system, our endocrine system, and our immune system.

For example, our body might turn up the protective dial on our motor system if we find ourselves in front of a moving bus — turning up the motor dial becomes the action of moving out of the way of the bus as quickly as possible. We do this instinctively, based on our knowledge of what a bus will do to our life if we don’t move.

Our pain system behaves in a similar fashion. We cannot always see that it’s happening, but it is happening nonetheless and it’s happening very quickly. It’s as if we were our very own superheroes, in a way — it’s awesome.

Pain and Protection

Let’s dive a bit deeper and take a look at one person’s story to provide us with some context on this notion of turning up our protective dial based potential tissue damage.

This story is that of a man who arrived in the emergency room with excruciating painful symptoms after jumping down onto a 15 cm nail. Because of all of the protective systems working together, he felt very real, very painful sensations — enough to bring him to the hospital. They were also acute enough that the doctors had to sedate him to calm him down so that they could remove the boot and inspect the foot.

As luck would have it though, the nail had missed his toes and foot entirely. It hadn’t even penetrated his skin.15

If we take a moment and reflect on how this could be possible, we start to gain awareness about the protective nature of pain. How can a person experience pain when there is no tissue damage? Ultimately, it’s a combination of all the body’s systems working together to protect it. This story, and many others like it, tell us a wealth of knowledge about pain, but again, only scratch the surface to how complex this topic actually is.

When it comes to pain, bio-plasticity can either work for us or against us. Ultimately this means we have the capacity to learn and can teach our bodies to do some pretty amazing things. To adapt to new situations, turning down the dial so to speak.

In the end, pain as a protective mechanism is quite amazing. It is important that when we experience a painful sensation, we work to approach it with curiosity, rather than fear, ultimately viewing pain as a friend, as our fierce protector.

Being curious about the sensation of pain, and how the entirety of our personhood might be affecting our feeling of pain, can empower us to be unafraid of our own bodies. To know that our bodies are not under attack when we feel pain, that we aren’t damaged goods. That we are, indeed, the most capable, most intelligent, most advanced species in the world.

Pain and why we feel it, is a result of these incredible advancements within our protective systems. In the end, we only get one body and it will go with us everywhere, so learning to love the intelligence of all pieces of it, can go a long way for our overall health.

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About the author:  Dr. Ellie Somers

Dr. Ellie Somers is a physical therapist of 10 years, with a special focus on treating the female athlete. She has a background in sports performance and rehab, including extensive training and education in the science of pain. She started her practice, Sisu Sports Performance & PT, in Seattle, WA with the goal of empowering female clients to help them reach their unlocked potential. She hopes to keep women actively engaged in sport and activity for their lifetime. Dr. Somers has spoken at the Women in Physical Therapy Summit in New York City as well as at several continuing education courses and professional conferences. She is a lover of soccer, running, heavy things, craft beer, and the great PNW. You can follow Dr. Somers on Facebook, Instagram, and Twitter!


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