By Ariana Besse (B.Phty Hons)
September is National Pain Awareness Month. This is the first time it has been brought over from USA to Australia. This is an important topic to discuss and there is a lot more to it than what appears on the surface. This blog series complements the 4 pain videos created by our lovely physiotherapists, Zac and Matt. Throughout this series, we are going to cover how pain works and what the body considers to allow this experience when pain becomes unhelpful, pain in the brain and how we as physiotherapists can help with your experience with pain.
Firstly, what is pain?
Pain is the resulting experience from numerous different inputs into your brain. There is no one sensor from your body that says, “this is pain”. Your brain receives inputs and decides whether there is a need for a protective response. Your body’s best way of protecting you is by making the movement hurt because then you generally stop doing it.
There are various inputs your body can recognise and send to the brain. These include pressure, mechanical, thermal, chemical, and nociceptive sensors. These receptors are like dials, giving a small or large input. Nociceptors (nociceptive sensors) are a fancy way of saying the threat receptor, and they give your brain information regarding the degree of danger. This is a great way for your body to tell your brain to pay particular attention to this stimulus. For example, when you put your hand on a hot stove, you stimulate the appropriate receptor (thermal, chemical, pressure, nociception). All this information goes up into the brain stem, into the brain, and other areas not of interest to us at this stage. Essentially, this is the stage where your central nervous system and brain decide whether the stimulus is threatening or not.
The Experience of Pain
So the experience of pain is output or response. There is no specific pain receptor nerve. It is a collective input from various receptors, and pain is the output. It is designed to protect us from hurting ourselves. It is also important to recognise that the pain experienced is not only the information from the input but also the context of the situation e.g. our learnt experiences, beliefs, and pain “memories”. These also come into the mix. Returning to the hot plate example, our brains have learnt hot plates are hot and that experience is going to hurt, even before it has computed the input from the receptors at the time of contact.
A story from Matt: I was experimenting with this pain science myself, and I pressed my hand down on a cold piece of steak while it was on the hot plate. Due to the high input coming from the thermal sensors, I actually felt burning. It was my expectation of being taught that putting my hand on a hot plate was going to hurt that resulted in my heightened experience of danger. It really shocked me and I couldn’t believe it myself.
In summary, the experience of pain is a result of the different senses coming in and the context e.g. memory, previous experience, beliefs. It is okay to experience some level of pain, but it becomes important to understand more about pain when there is no obvious reason why you are experiencing SO MUCH. More about this in the next blog…
- Butler, D.S., & Moseley, G.L. (2016). Explain pain(2nd [updated] ed.). Noigroup Publications.
- Moseley, G.L., & Butler, D.S. (2017). Explain pain supercharged: the clinician’s manual. Noigroup Publications.
For more information, check out the following video of Matt and Zac.