Pain Neuroscience: Building the Bridge Between Mental and Physical Health

By: Lauren Smith, SPT

Jimmy was a 10-year-old boy with no history of illness or neurological disorder when he woke up one morning with searing pain in both of his legs. He was rushed to the hospital, unable to walk or even move his big toe. After extensive testing, he was cleared of all pathologies and musculoskeletal problems, leaving everyone to wonder what the cause of his excruciating pain and paralysis could be. It later came to light that Jimmy was the victim of severe bullying at school, which had created in him a desperate need to escape daily classes and keep himself safe at home. Evidently, his body had decided to take matters into its own hands. Doctors eventually determined that Jimmy’s symptoms, while debilitating and agonizing, were a creation of his own subconscious mind—a sort of protective response. In the same way our brain sends pain signals to pull our hand away from a hot stove, Jimmy’s brain was telling him to stay away from school. This brings us to the fascinating topic of pain neuroscience.

It has long been hypothesized that our mental and physical well-being are closely intertwined, but the connection between mind and body has become increasingly understood among healthcare providers in recent years. With the shift in our culture to better recognize and address mental health concerns, in addition to advancements in psychology-centered research, an opportunity was created to comprehensively examine the bridge between physical and mental health. It is the establishment of this bridge that has allowed the medical field to begin unraveling the intricate physical and psychological implications of how we experience pain.

To understand the nuances of this connection, we must first understand how pain works. Pain is ultimately a decision made by the brain based on its assessment of the information received from sensory systems throughout the body. However, the same areas of our brain that process pain are also responsible for recalling memory, generating emotion, and creating social context, among other functions. This integrative structure allows us to remember and learn from painful experiences, and even differentiate between good pain (like a massage) and bad pain (like a nail in the foot). The consequence of this overlap is that significant social and emotional stressors can impact how the brain perceives and responds to a stimulus, whether it’s harmful or not. Heightened emotions such as stress, anger, or grief can trick the brain into thinking there is a painful stimulus, resulting in pain that persists throughout the body with no physical cause. This can manifest on a large scale, like in Jimmy’s case, or on a smaller scale, such as chronic migraines or back pain. In either case, it is crucial to recognize that the source of pain is not in the muscles or nerves but in the mind.

As with most bridges, the connection between physical symptoms and mental health is a two-way street—in the same way psychological stressors can cause physical pain, persistent pain can also cause a decline in mental health. It has been found that chronic pain can cause chemical changes in the brain that result in decreased neurotransmitters such as dopamine and serotonin, the same players that are suppressed in major depression. Persistent pain can also cause structural adaptations in the memory and emotion centers of the brain, inducing emotional and cognitive changes to our psyche. This is one reason why individuals with chronic pain often suffer from memory loss—the cognitive load of their pain is simply too much. Just as we can get used to the loud humming in an airplane (though it may still damage our ears), our body gets used to pain, making space for it in the brain at the expense of other cognitive functions. As you can imagine, this two-way street can easily spiral into a vicious cycle: emotional stressors cause exaggerated pain, which results in a decline in mental health, leading to more pain and further physical decline—on and on until you don’t know how it even began. That is, unless we fight back.

After months of physical rehabilitation and counseling, Jimmy returned to a normal life with no residual symptoms of his incident. This is the good news: If you can understand your pain, you can beat it. This kind of pain can’t be fixed with stretching and exercising—though that could certainly help with some of the compounding symptoms—it must be addressed at the source. Mindfulness activities have been found to be especially useful in the treatment of chronic pain, as well as stress relief strategies and breathing techniques. Physical therapy has proven effective in retraining the nervous system through the utilization of sensory desensitization, motor imagery, and mirror therapy, among other techniques. Studies have shown that even just receiving education on the nature of persistent pain can lead to improved outcomes. Consulting with a certified psychologist could also be the right choice to help you get on top of your symptoms.

It’s important to recognize that even though the source of the pain is not physical, that does not make it any less real. Though the mysteries of our brains will never cease, we know that mental health and physical health are endlessly intertwined, and both must be addressed to achieve optimal health and quality of life.

Below are some resources to better understand the neuroscience of our pain system, as well as references for the research mentioned above.

Patient-friendly Google Slides:
https://www.retrainpain.org

Tame the Beast—It’s Time to Rethink Persistent Pain (5-minute video):
https://youtu.be/ikUzvSph7Z4?si=bpdVxZv6vphJobPG

References:

1. Yang S, Chang MC. Chronic Pain: Structural and Functional Changes in Brain Structures and Associated Negative Affective States. Int J Mol Sci. 2019;20(13):3130. Published 2019 Jun 26. doi:10.3390/ijms20133130
2. Vadivelu N, Kai AM, Kodumudi G, Babayan K, Fontes M, Burg MM. Pain and Psychology—A Reciprocal Relationship. Ochsner J. 2017;17(2):173-180.
3. Baller EB, Ross DA. Your System Has Been Hijacked: The Neurobiology of Chronic Pain. Biol Psychiatry. 2017;82(8):e61-e63. doi:10.1016/j.biopsych.2017.08.009
4. Peters ML. Emotional and Cognitive Influences on Pain Experience. Mod Trends Pharmacopsychiatry. 2015;30:138-152. doi:10.1159/000435938