- $179.95 for three manual physical therapy sessions plus instruction in corrective exercises ($580 value)
Nerves: The Body’s High-Speed Highway
Whether from an injury or chronic condition, pain is made possible by our body’s nerves. Read on to learn more about these perception pathways.
Nerves are like an intricate network of power lines that runs throughout your body, carrying simple telegrams—“OW STOP THAT HURTS STOP”—to and from the brain. These telegrams come in the form of electrical impulses, which tell the brain everything from when to breathe to which of your muscles is sore. Most of the body hosts what is known as the peripheral nervous system—a series of nerves and receptors that control both voluntary and involuntary movements. When you experience pain in your hip, for example, the receptors around the hip initiate a signal that races along the peripheral fibers on its way to the brain. As the signal moves from nerve cell to nerve cell, it passes over junctions known as synapses, firing neurotransmitters across each minute gap. Once it reaches the spinal cord, the signal enters the central nervous system, which consists of the spinal cord’s 31 pairs of nerves along with the brain. The nerves in the spinal cord process the message and forward it to the brain, where it’s relayed to three different areas: one that pinpoints the pain’s location, one that processes its cause, and one that elicits an emotional and physical reaction. The entire process, from sharp pain to audible wince, is virtually instantaneous.
Not all pain is the same intensity, of course. Specialized nerve cells throughout the body control just how strong a pain signal comes across. One hypothesis, known as the “gate-keeper” theory, holds that these cells can leave the pain gates wide open to broadcast an urgent signal loud and clear (touching a hot stove, for example), but they can also narrow the opening when the stimulus is relatively minor (touching a microwave) or when natural pain blockers such as endorphins mute the pain. Competing sensations can also dull the signals, which is why massages can help assuage aches and pains. Still, there are many individual factors that can affect pain perception, including a person’s attitude and cultural background, which is why no two people react to a paper cut or fallen anvil in quite the same way.