Learning how the body responds to pain can help people understand recommended treatments and develop strategies to minimize chronic pain.
The Gate Control theory of pain,1 explains the elements—aside from the physical injury—that influence how pain is perceived.
How Pain Signals Are Relayed
Pain signals from throughout the body are sent along the peripheral nervous system, meeting in the spinal cord. According to the Gate Control Theory, a number of factors determine which pain messages are allowed to get through the gate and reach the brain, such as:
- Strength of the pain message
- Competing messages, such as touch or heat
- Brain signals giving high or low priority to the pain message
A key element of the theory is the concept of a gate that allows pain signals to reach the brain when it is open, and blocks the signals when it is closed. When a quick signal from a nerve fiber can close the gate, it can keep the slower messages from getting through, resulting in less pain. So, the first area where pain can be influenced is at the spinal gates. However, there is a second level at which pain perception can be influenced and that is in the brain itself. Once the pain signal is allowed through the spinal gate, the brain can amplify it, decrease it, or ignore it altogether.
Various cognitive (thoughts about the pain) and emotional (depression, anxiety, etc.) factors will determine what happens to the pain signal. Consider the example of having a stomachache. If the individual believes the stomachache is due to a spicy meal the night before, the pain will be experienced much differently than if he or she firmly believes it is due to stomach cancer (even if it is not). There are many other examples of how the brain influences the experience of a pain signal, but those are beyond the scope of this introductory article.
Therapies Using Gate Control Theory to Reduce Pain
One of the most powerful results of the Gate Control Theory is how it has influenced and explained why certain pain treatments are effective. The concepts outlined in the Gate Control Theory are often used to explain and develop pain relief treatments, such as:
- Transcutaneous Electrical Stimulation (TENS), spinal cord stimulation, and peripheral nerve field stimulation offer counter-irritants—a buzzing or tingling feeling—to compete with signals of chronic pain. This is a more technical approach to the same process discussed earlier of rubbing one’s head after banging a cabinet.
- Acupuncture's thin needles activate small pain fibers designed to close pain gates.
- Music therapy and auditory interventions tap the power of distraction, allowing the brain to send a signal down the spinal cord to close the pain gates while also minimizing the pain signal arriving to the brain itself.
An awareness of ways to moderate pain by opening or closing pain gates can be applied to daily life. Sensory, cognitive, and emotional factors that can close spinal nerves gates can all be used for chronic pain management. A mix of sensory, cognitive, and emotional chronic pain management strategies should be part of everyday life for anyone who suffers from chronic pain.