A look back through time to see the evolution of our understanding of pain.
To understand current pain theories and perspectives, let’s take a look at where it all began. As with so many things in life, you can’t really understand where you are unless you know where you’ve been.
The Ancients: Greek and Roman philosophers debated the origins of pain. They had a difficult time differentiating between emotional and physical pain. The pain a person feels during a time of grief was thought to be the same as the pain from a broken arm. Hippocrates felt that pain was the result of an imbalance of humor or fluids in the body. Plato advocated that pain and pleasure went hand in hand and were emotional in nature. He said that pain emanated from the heart.
None of the early philosophers connected the brain to pain. Later, closer to the time of Christ, physicians began to develop a rudimentary understanding of the body through the dissection of both animals and humans. Physicians began to think that pain was a disease all of its own. Ancient physicians spent long hours cataloging pain, its characteristics, and their theories, but they were still baffled as to where it came from or why it took hold in certain areas of the body.
Religion: In early civilizations and even well into the modern era, religion dominated everyday life and controlled scientific and medical theories. Religions had their own beliefs on pain and where it came from. According to most religions in ancient times, pain, particularly chronic pain which they found extremely puzzling, was sent by God to punish or test a person. It was, therefore, something to be borne to the best of one’s ability. It was often purposely not treated for fear of interfering with God’s will.
This began the stigma that a person with pain deserved it, and they were often judged as an evil sinner since they had been given such torment. In scientifically unenlightened times, many religions capitalized on the concept that pain was punishment and the only way to be free of it was to come to church and repent. These attitudes and beliefs muddied the waters of understanding around pain and laid the foundation of prejudices that persist to this day.
René Descartes: Fast forward to the Renaissance. Science, art, philosophy, and medicine all took huge leaps forward during this time. René Descartes, a French scientist, and philosopher claimed that pain came from the brain. He was the first to ever suggest this. His study focused on phantom limb pain and since there was no limb to actually feel pain, he concluded that pain must come from the brain. He also proposed that pain was tied to the soul which lived in the brain. The soul was whole even if the body was not and could cause pain in an amputated part of the body. The interesting part of Descartes’ theory is that he included the concept of the soul to appease the all-powerful Church. Even with this compromise, Descartes opened the door to the understanding that the brain was a key component of pain, though it would be centuries before the complete connection between the brain, the nervous system, and the pain was made.
Pain Theory Evolution: An early theory, called the Intensity Theory, stated that pain was triggered as an emotional response to stimuli that were more intense than normal. It claimed that the more intense the stimuli, the more intense the pain response. In the late 1800s, another theory developed that advocated that the body had receptors for pain. Similar to the receptors in the eyes and ears that allow us to see and hear, this theory went on to say that there was a specific area of the brain that pain receptors connected to. The pain continued to intrigue and confound physicians well into the 1900s. As scientific advancements were made, pain theories expanded.
It wasn’t until the mid-1900s, after World War II, that medical science had enough information about the nervous system to put together a theory about how pain was processed along with the central nervous system. The Gate Theory described how pain impulses traveled up the spinal cord and through a complex system of nerves until, if it was allowed past the ‘gate,’ the brain processed the impulse and sent a response. The Gate Theory went one step further and suggested that the state of mind of an individual could control how easily the ‘gate’ was opened. For example, in someone who is depressed, pain impulses travel more freely up to the brain. This theory was the first to put all the major players together, but it was still a bit off the mark and didn’t resolve the mystery around chronic pain.
Today’s Leading Theory: Despite all the advances in modern medicine, comprehension of the nervous system and pain still needs to continue to develop, though we are getting closer to putting all the pieces together. The Biopsychosocial model evolved between the 1950s and 1970s and is still considered by many practitioners to be the most accepted pain theory. It takes into account not only the biological components of pain but acknowledges how an individual’s behaviors and mindset influence that person’s pain.
Out of all the pain theories, this was the first one that even attempted to deal with chronic pain. This model says that there are four elements of pain. First, you have the signal sent to the brain called nociception. Next, you have the response from the brain which is defined as pain. The last two elements are pain behaviors and suffering. Pain behaviors refer to how a person acts when they are in pain.
For example, do they ‘push through the pain’ or do they stop moving entirely? Suffering involves the emotional and mental response to pain. Both of these elements vary widely from person to person and are crucial factors in understanding chronic pain. Thanks to this theory, the development of pain management teams that include multiple different medical disciplines has begun to take root in medical communities. This is a tremendous step in the right direction.
This is a high-level review of the evolution of pain theories. We’ve come a long way in our understanding and treatment of pain, but as always, there’s still more to be learned.
Precision Pain Care and Rehabilitation has two convenient locations in Richmond Hill – Queens and New Hyde Park – Long Island. Call the Richmond Hill office at (718) 215-1888, or (516) 419-4480 for the Long Island office, to arrange an appointment with our Interventional Pain Management Specialist, Dr. Jeffrey Chacko.
