Most people think about pain as a simple cause-and-effect process. For example, if you touch a hot stove, you probably assume that the nerves in the skin feel how hot the stove is and signals are sent to the brain to trigger a feeling of pain.
Research shows, though, that pain signaling, as well as the sensations the body perceives as pain, can be more complex than this scenario.
Read on to learn more about why we feel pain and gain a greater understanding of the gate control theory of pain.
Why Do We Feel Pain, and What Does It Mean?
Acute pain serves a purpose: In small doses, it functions as a warning that keeps us from harming ourselves. Whether you touch that hot stove or push your body past its limit during a strenuous workout, your body's reaction is communicating to you that you should stop doing whatever it is that’s causing the pain.
Severe pain, like a broken arm or a heart attack, signals to our conscious brain that there is something very wrong. Pain that’s an obvious response to a pain-causing stimulus is called nociceptive pain. This type of pain may not be simple to fix, but it’s obvious where the problem is coming from. Nociceptive pain can also occur after an injury when there’s an inflammatory response in the injured area.
In contrast, chronic pain isn’t always connected to external stimuli, and many people who live with it find it difficult to describe.
In fact, there are many different types of pain. Think about hitting your head on the sharp corner of an open kitchen cabinet. This would be an acute, inflammatory type of pain. You might also feel a dull pain in your head if you were getting a tension headache, or you might feel a burning, tingling sensation in your neck and head if you have a pinched nerve in your cervical spine. You may be unaware that different types of pain are classified into specific categories:
- Visceral pain: This type of pain occurs when the internal organs are damaged or sick. It can be difficult to know which organ is causing the pain because internal organs have different pain pathways than the outside of your body does.
- Neuropathic pain: This pain occurs when your nerves aren’t functioning correctly. It might feel “electric,” and you might experience extreme sensitivity to touch and temperature.
- Nociplastic pain: This type of pain is one of the potential end results of nociceptive pain that lasts for a long time. In cases of chronic pain conditions like fibromyalgia and recurring tension headaches, a person might have persistent pain even if the body doesn’t show any signs of damage.
What Is the Gate Control Theory of Pain?
Few researchers want to dull the human response to injury, because this pain functions as a safety mechanism. What about the many people who live with chronic pain, though? Some experts think that these people can be helped with the gate control theory of pain — or, the idea that you can simply close the gates to unhelpful pain.
The gate control theory of pain was formulated in 1965 by a neurobiologist and a psychologist who wanted to propose that spinal nerves act as gates to let pain travel through to reach the brain — or close these gates and prevent pain messages from getting through at all.
Open gates. When the gates are open, you feel too much pain for too long. People with chronic pain conditions have gates that stay open even when they should be shut.
Closed gates. If you’ve ever injured two parts of your body at the same time, you understand that pain signals “compete” for our brain’s attention. It’s difficult for your brain to process pain from both areas at the same time. Other methods of closing certain gates include self-relaxation exercises and medication.
What Affects Whether the Gates Are Open or Shut?
Emotions. Have you ever meditated with the hope that you'll calm down and your stiff, sore muscles will relax? Negative emotions like anxiety, depression, and chronic stress can increase pain. Once you’re in the cycle of depression and pain, for example, it can be difficult to know whether your depression is making your pain worse or whether your pain is worsening your depression. They may each have an effect on the other. This is why it’s important to acknowledge the link between mental health and chronic pain.
Brain disorders. Your brain is the processing center for pain, so if part of the brain isn’t working correctly, you might not process pain in a healthy way. People with schizophrenia, for example, often don’t perceive pain in the same way as their mentally healthy counterparts. Researchers think that understanding more about this link between schizophrenia and pain sensitivity could help doctors understand the condition as a whole.
Stronger signals. As a child, if you bumped your head, a relative might have immediately told you to rub the affected spot. This isn’t an old wives' tale — it’s actually a great example of “closing the gates” of pain. When your brain perceives another, stronger signal coming in, it doesn’t pay as much attention to the first, painful signal.
Drug use. Both illegal and prescription drugs have a reputation for affecting example how the body processes and perceives painful stimuli. Opioids in particular are prescribed for pain, and they have a strong “gate closing” effect — usually, at least. Overusing opioids can lead to an increased sensitivity to pain over time.
Central sensitization. People with chronic pain often experience a heightened pain response to nearly everything. When a person lives with chronic pain on a daily basis, their nervous system develops an abnormal response to everyday stimuli. Clothing may hurt, and walking around may be too painful to bear. In other words, things that shouldn’t be painful are being processed as if they are.
While this sounds dramatic, it’s the reality for many people with conditions like rheumatoid arthritis or fibromyalgia. In this situation, the body’s gates are left wide open and often need medical assistance to shut again.
Can We Change How Our Bodies Perceive Pain?
If you live with chronic pain, it can be discouraging when your current treatment isn’t working or when the pain returns time after time. The gate control theory of pain example offers insight into the causes of pain and why certain experiences are more painful than others.
Closing these gates through relaxation exercises, taking appropriate medications, and using treatments like acupuncture to distract the body from the origin of the pain might provide some relief.
Get in touch with your doctor if you have questions about your personal pain management plan.