Why acute pain can be a good thing, but chronic pain is not
How does Pain work?
First and foremost, pain is an essential survival mechanism and our built-in danger alarm system. It is there to protect us, keep us safe, and alive.
Pain equals a danger signal (not necessarily real danger, though, as we will soon learn).
We experience pain to protect us from causing further damage to our body, e.g., it keeps us from continuing to run on a sprained ankle.
Let's look at the example of spraining an ankle in some more detail:
1. We roll an ankle.
2. Sensory receptors in the skin and ligaments of the foot send messages via nerve fibers to the spinal cord, where sensations are registered.
3. The messages get relayed to the brain where they are perceived and interpreted.
4. If there is any perceived danger of tissue damage, the brain will produce and send a pain signal to keep us from further injuring the area.
5. We feel pain in our ankle (within a split second) and take our weight off this foot to protect it so it can heal.
6. Depending on the level of perceived threat, the brain can upregulate or downregulate the pain signal, meaning the pain can increase or decrease.
7. The body's self-healing process begins: swelling occurs, inflammatory agents and cytokines are dispatched to the injured area, and tissues repair themselves.
8. Any injury typically heals within approximately 6-12 weeks.
So why am I still in pain if my injury has healed?
If pain persists past the 3-month mark, it is called 'chronic' or 'persistent pain'.
Chronic pain is very different from acute pain. It does not function as a danger alarm system anymore. After all, the danger (the injury) has healed. Our protection system is now malfunctioning: it gets triggered by normal, safe bodily sensations that the brain misinterprets as dangerous, and our brain's 'pain switch' gets stuck in the on position.
The pain is 100% real, but it's neuroplastic pain. We need to target the brain, not the body, to treat it.
Research has shown that upwards of 85% of chronic pain and other persistent symptoms are NOT caused by structural damage to the body but by misfiring neural circuits in the brain. Because our brains are made for learning, neuroplastic pain can become like a skill we have learned.
This is good news because these learned pathways can also be unlearned.
The first step is to understand why the brain misinterprets safe signals in the first place so we can focus on preventing it in the future. Then, we can harness the brain's fantastic flexibility to develop new neural pathways. Using Pain Reprocessing Therapy, we can rewire the brain and unlearn painful symptoms.
So, what is the root cause of neuroplastic pain? Why do our brains make this mistake? What is the fuel that keeps the pain going? Maybe, surprisingly, it's fear.
Fear is the fuel for chronic pain.
It is interesting to note that our nervous system can become hypersensitive due to pain or the fear that arises from pain. It is natural for us to feel worried, anxious, and fearful in response to pain. We might think, "This pain feels terrible!" or "How long will it hurt this much?" or "What if I don't get better?"
The brain goes into high alert when experiencing these thoughts and feelings. As a result, all signals from the body's sensory nerve endings are now perceived as an even greater threat. This leads to even more pain which leads to more fear, which leads to more pain. And the pain-fear-pain cycle continues.
Over time, smaller and smaller signals are being picked up and interpreted as dangerous by our brain. That's when the protective danger-alarm system turns into an overprotective, malfunctioning false-alarm system.
There are many different factors that play into the development of a hypersensitized pain system. After all, pain is a biopsychosocial experience. And that means pain and the onset of pain will be different for every individual.
Pain is a decision made by the brain
All pain is real. It hurts. It's not imaginary. It's real. But ALL pain is constructed by the brain, ALL the time.
Whether or not the pain constructs a pain signal depends on whether or not your brain perceives a threat to you. After all, its only goal is to keep you safe and alive. If the brain deems you in danger, it will do ANYTHING to keep you safe – even if that means sending you to bed with a debilitating backache, neck pain, or migraine.
When making that threat assessment, the brain considers thoughts, beliefs, perceptions, emotions, past experiences, context, and input from your body (Edwards et al., 2016). All of these pieces of information together determine how you experience pain.
‘Really?’, you may think. Really! The brain can produce pretty much any physical symptom you can imagine (pain, tension, tightness, swelling, redness, tingling, throbbing, anxiety, panic attacks,… you name it). Many scientific studies have proven the connection between our mind and the body.
Hurt does not always equal harm
Today, we understand that tissue damage is not a good indicator of pain, and the theory that hurt does not always equal harm is well-supported by research.
Case study 1: A nail in the boot
Take the famous example of the British construction worker who jumped off a scaffolding onto a 7-inch nail that went straight through his boot (Fisher et al., British Journal of Medicine, 1995). In excruciating pain, he was rushed to the hospital by ambulance and given fentanyl intravenously for the pain en route, unsuccessfully. He was in absolute agony. In the ER, the doctors carefully removed the boot, only to discover that the nail had gone right between his toes. There was no injury, no tissue damage, not even a scratch. When the man realized this, his pain stopped immediately.
This is the most famous, well-documented example of a case where the brain produced pain in the absence of any injury. But make no mistake: despite the absence of injury, his pain was very real. So what happened?
Sensory receptors in the man's body reported to his brain that there’d been an accident, that a nail had penetrated his boot. His brain, perceiving a potential threat to his safety and well-being, used context to determine what had occurred, collecting information from his five senses (including the visual of a nail sticking out of his shoe!), knowledge of the dangerous work environment and its risks, his co-workers’ horrified faces, the audible gasp they let out, and other data to make an assumption about what had happened and how to respond.
Thoughts, beliefs, and emotions, including panic and fear, set off a cascade of biological and neurochemical processes. His brain, synthesizing the sum total of this information, decided that he was in danger, so it made pain to protect him. In this case, real pain was generated entirely as a result of factors having nothing to do with actual tissue damage—yet was as intense as if he’d been gravely injured.
Case study 2: A nail in the head
But it also works the other way around. Take the example of yet another construction worker. He was working with a nail gun, which malfunctioned and clocked him in the face (Dimsdale & Dantzer, 2007). Other than a small bruise on his jaw and a mild toothache, he felt fine, and he counted his blessings. When he visited his dentist six days later, an x-ray revealed a 4-inch nail embedded in his head! The nail had pierced his cerebral cortex, putting him in potentially grave danger. However, because contextual cues failed to put his brain on high alert, he didn't feel much pain.
So, we can conclude that the existence of pain is not a good predictor of injury or structural damage to the body. Whether or not we feel pain depends on whether or not our brain perceives danger.
Perceived Danger Pain
This is a term coined by Dan Buglio. It aptly describes neuroplastic pain (aka nociplastic pain, mind-body syndrome, TMS, neural circuit pain, neural pathway pain, central sensitization, functional pain, etc.). It's pain that is being constructed by the brain in response to a perceived danger threat.
So, what can cause our brains to perceive such a threat?
Research shows that stress or emotional distress activates the same danger signal in the brain as an actual physical injury. Stressful events in our lives, especially during childhood, can sensitize our nervous system and make it more likely to activate the danger alarm system later in life.
That doesn't always have to be 'big T' childhood trauma. An anxious, emotionally absent, or overly critical parent, feelings of neglect, a bullying classmate, etc., can all begin to put our brains on high alert. Adult stresses like relationship issues, getting married, divorce, moving, a new job, the death of a loved one, car accidents, and financial worries can then build on that already sensitized nervous system. Symptoms can creep up or become chronic.
Research has also shown that there is a higher risk for the development of neuroplastic pain/mindbody syndrome/psychophysiological disorders in people who
Put more pressure on themselves
Who are more self-critical and self-blaming
Have perfectionistic tendencies
Feel more obligations
Have a stronger sense of duty
Take responsibility for external problems
are overly conscientious and caring about others,
especially to the exclusion of doing things for themselves
Let's summarize some key facts about pain
Pain is always real
Pain protects us and promotes healing
Chronic pain overprotects us and prevents recovery
Chronic pain is very common and can affect anyone
Pain is a marker of perceived threat
HURT does not always equal HARM
Expensive procedures, surgeries, or medications are often not the best answer
Understanding your pain is a key factor
Many factors influence pain
There are many ways to reduce pain and promote recovery
Recovery is possible!
Leake, et al 2021 PAIN; Flippin' Pain Health education campaign, UK,