Ouch! Your daughter snatches her finger back at the first prick of a rose. Eek! Your son jumps back the instant his bare feet touch your sunbaked deck. Our reflex response is a blessing, prompting us to withdraw at the first sign of trouble and preventing worse harm.
Pain protects us from bigger problems—not just outside but inside. The pain of an inflamed appendix, for instance, often drives us to seek medical care before the appendix ruptures. As a medical doctor and a Christian, I’ve seen innumerable cases where such pain has helped people in this sin-cursed world.
Yet pain still raises some natural questions. Did God design us to feel all this hurt from the very beginning, even before Adam’s Fall? And why does pain sometimes afflict people even after the root problem has gone away or when there is no obvious cause?
Basic to Our Anatomy
If you look at human anatomy, God clearly designed us to sense and respond to our surroundings. Although we often think of nerve endings that detect painful stimuli as “pain receptors,” this shorthand description is not strictly accurate. Most parts of our body are richly supplied with unspecialized nerve endings to help us sense the world around us.
Pretty much every place on and in your body—except your brain—has these receptors. They are especially common on the skin, inside the walls of arteries, at joints, and in the tissue that covers our bones (known as periosteum). They sense temperature, pressure, stretching, chemicals, and many other things. Among those chemicals are acids and the ones produced by inflamed tissues.
Once a stimulus increases beyond a certain threshold, the body interprets the signals as pain. And that’s a good thing, else we would not know to do something to stop it.
The nerve endings that send pain warnings are called nociceptors because they detect “noxious” stimuli. Once nociceptors are stimulated beyond the pain threshold, nerve impulses travel to the spinal cord and then to the brain. The first signals to reach the spinal cord travel along a fast network of nerve fibers (insulated with a substance called myelin for this purpose), so the spinal cord can generate a reflex response quickly, even before the message reaches the brain. This causes the appropriate muscles to recoil from danger almost instantaneously.
In addition to triggering the reflex response, the same specialized network of nerves sends awareness of the painful stimulus to the brain.
The skin, as our first line of defense, is covered with nociceptors. They are designed to send information to very specific parts of the brain to help us precisely localize the source of a painful stimulus and eliminate it. Without our consciously thinking about it, the brain may signal the body to hold still or to tighten up nearby muscles, protective actions to prevent further injury or aid recovery.
Meanwhile, a network of unmyelinated nerve fibers carries a second version of the painful news to the brain a little more slowly. This is the so-called “slow pain.” The information from slower sensory nerve fibers travels to several regions of the brain, bringing pain to our attention in a number of ways. The brain can then formulate a quick plan to prevent further injury.
These well-tailored systems clearly speak of the wise Designer who lovingly created us to thrive in his world, even though it’s cursed.
Our internal organs don’t have the same need for a quick response. If you think about it, you really don’t need to jump when your internal organs are in danger; they are already shielded from outside threats. Instead, our internal organs require long-term care. So they contain lots of the slower nerve fibers that go to the brain, where you can formulate decisions about your next step. This explains why internal organ pain may be harder to pinpoint than a stubbed toe.
These two well-tailored systems clearly speak of the wise Designer who lovingly created us to thrive in his world, even though it’s cursed.
Unfortunately, some breakdowns occur in the process of communicating organ pain. One is known as referred pain. Our brains can mistakenly register pain from one internal organ as coming from another part of the body. For example, pain caused by gallstones is sometimes perceived as shoulder pain. Or pain from a heart attack can sometimes feel like pain from the left arm or jaw. Why is this?
Research continues, but we have learned that the nerves for both body parts that feel “referred pain” develop in the same place in the embryo; and in adults, the nerves still come from about the same place in the spinal cord. Scientists think mixed-up signals at this shared entry point explain referred pain.
No Reason for the Pain?
Many people are afflicted with another problem: pain without apparent cause. For instance, patients with a condition known as trigeminal neuralgia suffer severe pain at the slightest touch. Narrowing down the cause is complicated because people experience pain in so many different ways and turn it off differently.
A wound sustained during battle, for example, may not immediately produce the same pain sustained in a less emotionally charged situation. A seamstress who pricks her finger every day in the course of her work might not perceive the pain until she bleeds.
In a quest for solutions, researchers have learned much about pain. The sensory nervous system must play a sophisticated balancing act. The same receptors that sense pain are designed to appreciate the warmth of sunshine on our skin, enjoy a gentle breeze, or feel the touch of our beloved’s hand.
How does the body switch back and forth between pain and pleasure? Much is unknown, but we have some clues. Our ability to sense our surroundings is a good thing, and we certainly had it before the Fall brought suffering into the world. But the Fall has changed our perception of the world.
Research to find better ways to relieve pain offers hope for new and improved ways to control and even eliminate some forms of pain and suffering. Yet pain is an unavoidable reality because of Adam’s sin.
Thankfully, the Bible reveals that our Creator God is good. Short-term sorrow is a means to good, long-term ends. The Creator, whose name is Jesus Christ, became human and experienced pain as we do (Hebrews 4:15) and desires to take it away—permanently (Revelation 21:4). But he will do so in his timing and for his glory. Until then, we must trust in him (Romans 8:28).