Pain – Definition, Mechanisms & Self-Help

On this page, I will explain what pain is, what it means and how it is triggered.

If you want to find an overview of the different types of pain presented on this site, click on Overview in the navigation bar to your left.

1. Definition: What is pain?

Pain is a complex, uncomfortable and subjective experience, which is always made up of emotional and often sensory components.

It can occur because of potential tissue damage – hand over the hob – or actual tissue damage – burnt hand – or even be triggered by just such physical threats. This is often the case with chronic pain.

The actual or potential tissue damage, as mentioned above, triggers the sensory component of pain. Here we speak of nociception which, could be translated as “meaningfulness or significance of pain”.

Nociception is nothing other than the transmission of “danger signals” to the brain, usually triggered in the body due to some thermal, chemical or mechanical changes.

Pain is always real and always subjective!

  • The sensory experience of pain or nociception corresponds to the meaning of pain, which is danger.
  • The emotional experience, meanwhile, corresponds to the cognitive processing and evaluation of actual (nociceptive) or “imaginary” stimuli. In fact, it represents both what we feel as pain, call pain or consider to be pain.

When you see your doctor for a broken leg, you do not do it because it represents a danger to your body or because you know that your bones could completely break under additional stress, but because it hurts.

Let me point out that when processing these stimuli, our brain detects the sense, i.e. the risk of real or potential pain, while our mind, which is responsible for the emotional component, evaluates the level of pain.

The latter of course implies that the psychological and emotional make up of the individual have a profound influence on the “overall sensation of pain” and that pain is clearly subjective.

Finally, I again want to emphasize that nociception – often triggered by an injury or a sensory experience, is frequently involved in pain and can be the cause, but this is NOT absolutely necessary for it. For more information about this, see the chapter on the onset of pain.

Pain can also occur or persist in the absence of any injury or other condition; most of the time, such pain is purely psychological.

2. Meaning of pain

Pain is a mechanism that is fundamental to self-preservation, a defence mechanism against attack, which triggers a reaction that serves to reduce or minimize injury or illness.

Moreover, much the same or similar as can be seen in current scientific literature. But is this actually true? We could probably answer with both yes and no.

Furthermore, the pain ensures our survival and usually is a brilliant job of a warning function.

People who suffer from absolute congenital insensitivity to pain – congenital analgesia – are unable to feel any pain.

That means they can suffer serious injury and/or subject their joints to excess stress that ultimately results in damage. Such individuals do not immediately realize that they have bitten their tongue while eating, until they start bleeding from the mouth.

An ankle fracture will go undetected and they will continue to use the joint until it is completely destroyed.

Does our body warn us against cancer that spreads in us over the years, or the development of type 2 diabetes mellitus? Most symptoms appear when it is (almost) too late. In such cases, one cannot truly speak of a warning function.

It can be considered that pain usually has a warning function but this is not necessarily the case.

However, if you have a healthy, functioning body, then remember pain is nothing “bad”, though somewhat unpleasant, and especially serves to help keeping you safe from harm.

In most cases, that would be threats of a physical nature.  My current understanding of pain indicates that it might also fulfil a warning function in the case of “psychological aggressions or threats”.

We can usually consider pain as a kind of stop signal, which prompts you to pay attention to your body and mind without pushing them beyond their current (perhaps diminished) limits.

Pain is unpleasant, but causes no physical damage.

3. Types of pain

Pain can be classified in many different ways. In this case, when dealing with muscle and joint pain, we “only” study pain that has a myofascial origin or is due to overuse or too little use.

Such myofascial pain may, among other things, be triggered by

  • Fascial adhesions
  • Myofascial trigger points
  • Tender points
  • Myogeloses
  • Excessive muscle tension
  • Etc.

They all share the issue of “impairment” of the muscular and connective tissue structures.  This is presented in my article on trigger points, where I explain the main causes of muscular overuse.

Pain can be imaginary. However, you cannot imagine pain that is not there! Pain is always real!

4. Pain triggers (origin)

Pain is produced by our brain and only there does it become real. It is interesting to note that our brain has no pain centre.

In other words, there is no single location responsible for the triggering and consciousness of pain.

Rather, it is the interaction of different parts of the brain that produces pain or leads to the experience of pain.

When these regions are activated, certain mechanisms can be identified. These mechanisms are expressed by the simultaneous activation of different areas, and are characteristic of a pain experience, but differ from person to person.

Pain is very subjective and personal

4.1 The pain mechanism

I will give you an image to make it easier to understand. Imagine your brain is a big spider web.

Each node in this network communicates with a great number of threads and is indirectly connected to every other node via the threads.

Now imagine these nodes are clusters of neurons that take care of different tasks in the body – for example, controlling movement, treatment of emotions, sensory perceptions, etc. – and that the threads represents the neural connections between the nodes.

Different nodes could then be active simultaneously. These nodes would start to light up on our web whenever they are active and generate a specific activity mechanism, i.e. different nodes and threads would light up at the same time.

This is the mechanism I mentioned above. Let’s call it the pain mechanism.

This pain mechanism is processed in a specific region of the brain to become a conscious experience, in this case, possibly pain.

The stimuli of your environment, but also your thoughts influence your pain.

The question that now arises is: What triggers this pain mechanism that can lead to pain and what can influence it?

The pain mechanism can be triggered by different factors.

In most cases, it comes from sensory stimuli of our body. In other words, a bee sting, a sprained ankle, a broken bone, a sunburn, tension, etc.

Furthermore, thoughts or visual stimuli – seeing someone get hurt or beaten, for example – can activate the pain mechanism, thus triggering pain.

In addition to the stimuli that trigger the pain mechanism, the brain also receives other information that is processed in parallel. This acutely changes the pain mechanism and serves in the interpretation of the overall situation – enabling, for example, an assessment of the exact level of severity and danger of the situation.

Are you in danger?

The pain mechanism is triggered by the sensory input from your fingers if, for example, you cut your finger.

Now, you look at your wound – visual perception – and realize that it is not very serious, or a doctor is with you and assures you that it only a minor injury, this information is included in the processing of pain perception and will probably reduce it.

It does not hurt. You or your “self” are not in danger.

You could, on the other hand, be someone who is rather hysterical, and, let’s say, a professional violinist. As such, your main thoughts will be fixed on the time you won’t be able to play correctly and whether or not you will be ready for the concert in two days.

You feel threatened by the injury – rightly or wrongly – and give in to a catastrophe scenario.

These thoughts also affect the pain mechanism and the interpretation of the overall situation. You or the person you believe yourself to be – a violinist, in this case – is in danger.

The constant thought of the injury and the fact that you cannot play music leads to stress and increased pain that lasts longer than usual for such an injury.

In summary, we can say that pain can be caused by certain stimuli that trigger the pain mechanism in the brain, which is itself subject to modulation by other stimuli such as thoughts, visual perception, and so on.

The brain “constructs” an assessment of the situation for you using all of the incoming information, and decides whether, and how much pain you feel.

5. An overview of common daily pains

References

  • Butler, David, and Moseley, Lorimer. Schmerzen verstehen, 2. Aufl. Heidelberg: Springer, 2009. Print
  • Galizia, C. Giovanni, and Lledo, Pierre Marie. Neurosciences: From Molecule to Behaviour: A University Textbook. Heidelberg, New York, Dordrecht, London: Springer, 2013. Print
  • Gorczyca R, Filip R, Walczak E. Psychological Aspects of Pain. Ann Agric Environ Med. 2013; Special Issue: 23–27.
  • Melzack, Ronald and Wall, PD. The challenge of pain, 2nd ed. London: Penguin Books, 1996. Print
  • Melzack, Ronald. Pain and the Neuromatrix in the Brain. Journal of Dental Education, 2001;65(12): 1378 – 1382.
  • Swieboda, Paulina, Filip, Rafal, Prystupa, Andrzej, und Drozd Mariola. Assessment of pain: types, mechanism and treatment. Ann Agric Environ Med. 2013; Special Issue 1:2-7