How Pain Works and What You Can Do About It

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When you live with pain, it can affect every single part of your life and compromise your quality of life. But in order to know how to best approach pain and its treatment, it is important to first understand what pain is, what causes it, how pain works, and what purpose it serves.

Is Pain Universal to All Animals?

Pain might be the one sensation that is common to all animals. It is widely accepted that not only do all mammals feel pain but, most likely, all vertebrates do too. 

There are enough similarities in the common vertebrate physiology to suggest that, even though we aren’t sure about exactly how different species feel pain, we know that they do feel it.

Moreover, scientists claim that invertebrates too have the physiological capability to detect and react to harmful stimuli. Their reactions of withdrawing and escaping seem to confirm this theory.

In this sense, pain is one of the most universal sensory experiences, even if it does not present in emotional and psychological factors for all species.

Understanding Pain as a Protective Mechanism

Scientists don’t know exactly when living beings started feeling pain, but it is safe to say that it’s one of the oldest evolutionary protective mechanisms in nature and that it predates the human race.

Even though it is an unpleasant sensation, it is actually incredibly useful. Pain is the body’s reaction to the so-called noxious stimuli – stimuli from some sort of damaging experience. In that sense, pain is actually an adaptive trait – the evolutionary result of natural selection.

Simply put, the pain message tells us when we need to escape or withdraw from a damaging influence. This response helps us avoid more extensive potential tissue damage. It also reminds us to be careful with the affected area until our injury heals.

How Do We Feel Pain and What Is the Message Pain Sends?

Pain takes place almost entirely in the nervous system. It starts with an unpleasant stimulus, be it an injury or an internal inflammation. The pain receptors at the end of nerve fibres detect that stimulus. 

On the other end of this pain pathway is the spinal cord. When the stimulus triggers the pain receptor, it sends electrical signals up the neuron to the spinal cord. From there, the pain message is further relayed to the part of the brain called the thalamus. The thalamus sorts the pain signals and directs them to other parts of the brain – namely, the parts in charge of emotions, physical sensations, and thinking.

Pain perception is exactly that – perception. Pain is a construct in the central nervous system, or, more precisely, the brain and spinal cord. The pain stimulus is real, and pain is too, but perhaps not in the way you sometimes think of it.

The pain messages are quite literally a warning bell from the brain. It is the alarm signal the brain uses to tell you that your body is in danger. People who are born with a congenital disorder that prevents them from feeling pain or transmitting pain messages rarely live past the age of twenty-five.

The Difference Between Chronic Pain and Acute Pain

When we talk about acute and chronic pain, it pertains to the duration of the sensation.

Acute pain is temporary. It is caused by pain messages the moment the injury or inflammation is happening and goes away once the tissue has healed. Typically, pain that lasts under 6 months is considered acute pain.

Chronic pain, or persistent pain, can be present due to persistent tissue damage or inflammation. However, sometimes it lingers even after the damage has healed. In some cases, the pain is not a symptom but rather part of a pain disorder.

Chronic pain usually occurs when some part of the nervous system – like the receptors, the neurons, or the spinal cord – become easily activated or fail to function properly due to an injury.

Chronic pain often persists even when there is no visible damage, an occurrence called nociplastic pain.

The Characteristics of Pain

Pain is a subjective feeling. There is some indication that MRI scans of the brain might reveal the objective intensity of pain, but this method isn’t common practice yet.

In the meantime, pain is mostly measured through self-assessment. Accuracy is important so that the patient can get the best diagnostics and treatment.

In order to get the clearest possible picture, it is important to determine several characteristics of pain:

  • Intensity (from mild to severe pain, usually on a scale of 1 to 10)
  • Location
  • Duration
  • Alleviating and aggravating factors 
  • The descriptive quality of the pain – whether it’s a sharp pain, a stabbing sensation, throbbing, pressure, cramps, or some other feeling.

Types of Pain

Not all pain is the same, and neither are the ways it hurts. This depends on where the pain originates, as well as what types of nerves transmit the pain signals from the pain receptor to the brain.

Nociceptive pain

Nociceptive pain is pain from injury. It is the pain that occurs due to tissue damage or the possibility thereof. Arthritis pains are nociceptive. There are many reports of successfully using red light therapy for arthritis pain.

This type of pain gets its name from nociceptors – the pain receptors that register noxious stimuli. The stimulus in question can be heat, cold, chemical, or a physical force. These peripheral nerve endings then send the pain signal about the injury to the spinal cord and the brain.

Once the damage has occurred, it is usually followed by inflammation in the injured area. Inflammation is a useful body response that promotes healing. However, it can be extremely painful and even a gentle touch can cause intense inflammatory nociceptive pain.

Neuropathic pain

This type of pain arises from injury or damage to nerve cells or nerve tissue. Nerve pain is usually perceived as shooting or stabbing and it can be triggered even by a very light touch.

Persistent pain from damage to the nerves can easily become chronic pain so it is crucial to treat it in an adequate and timely manner.

Algopathic Pain

Algopathic pain is the kind of pain that occurs in conditions and disorders which cause long-term pain all over the body, such as fibromyalgia. In these conditions, the pain is the main problem, rather than a symptom of some underlying damage.

Visceral and Somatic pain

Depending on where it occurs, pain can be somatic or visceral.

Somatic pain is usually associated with the skin, muscles, bones, tendons, and joints. It is also the most common type of cancer pain.

Visceral pain is the aching pain that affects the internal organs.

All of the different types of pain can be either visceral or somatic.

Living With Pain and Pain Management

Living with pain is not only physically challenging but also mentally and emotionally draining. Chronic pain in particular can be a very trying emotional experience for patients and it is often accompanied by stress so great it can lead to depression and anxiety. That is why the treatment of pain often requires a multidisciplinary approach.

Treatment of pain usually includes not only physical therapy, but also significant lifestyle changes, like a diet change, reduction in stress, and increased physical activity. Additional treatments such as massages or non-pharmacological pain management tools can also be helpful.

One of the most effective ways to help your body manage both acute and chronic pain is red light therapy. Therapy using red and near-infrared light stimulates the body’s natural healing mechanisms which help reduce and, ultimately, get rid of the pain for good.