Pain plays an important role in overall health. Acute pain is a normal sensation triggered in the nervous system which acts as an alarm system for the body. When tissue is injured, peripheral nerves in the area send a shrieking signal to the spinal cord and brain. The usual result is a reflex that is processed in the spinal cord: you pull your hand away from the stove; you shift your weight off of the broken bone. All pain signals ultimately end in the brain, where they trigger thought (“that was dumb”), emotions (“tears”), memories and a complex array of biochemical events aimed at protecting your body from further harm.

With chronic pain, however the pain persists and the alarm continues to shriek uselessly long after the physical danger has passed, usually for weeks, months, even years. Somewhere along the line-maybe near the initial injury, maybe in the spinal cord or brain-the alarm system has broken down. What researchers have recently discovered is that prolonged exposure to this screaming siren actually does its own damage. Research has found that pain causes a fundamental rewiring of the nervous system. Each time we feel pain, there are changes that occur that tend to amplify our experiences of pain. That is why it is a mistake, despite our grin-and-bare it traditional attitude, to ignore or under treat chronic pain.

Clinical investigators have tested chronic pain patients and found that they often have lower-than-normal levels of endorphins in their spinal fluid. Investigations of acupuncture include wiring the needles to stimulate nerve endings electrically (electroacupuncture), which some researchers believe activates endorphin systems. Other experiments with acupuncture have shown that there are higher levels of endorphins in cerebrospinal fluid following acupuncture. Investigators are studying the effect of stress on the experience of chronic pain. Chemists are synthesizing new analgesics and discovering painkilling virtues in drugs not normally prescribed for pain.