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Where Did that Itch Come From?

Much of what goes on in our brains happens without our awareness. The cells in our brain constantly exchange messages with various parts of our body through nerve cells called neurons, which pass on messages via electrical impulses. We see, hear, feel, taste, and are aware of our body sensations and position, not at the end of our nerves, but in our brains.

Sometimes it is difficult to know whether the signals are real or imaginary. In the strange effect of “phantom limbs,” people who have lost limbs can still experience a variety of sensations, like itching, in limbs that aren’t there.

Unfortunately, it is very common to feel quite severe pain in the missing limb. Amputees sometimes have the urge to reach for an object using a missing arm, or step out on a leg they don’t have. This effect is apparently related to an image of the body that persists in the brain. The sensations that are felt in phantom limbs arise from within the brain itself.

The brain’s neurons send out impulses that inform it about the body it controls. The brain learns to recognize the body’s pattern of signals or “neuron signature.” The sensations experienced in phantom limbs indicate that our neuron signature is pre-wired into the brain. Rather than just taking information from the real world, the brain sometimes generates its own messages which can disagree with known physical reality.

So next time you go to scratch your arm, it might be worth checking to see if it’s still there.

Unless you’ve experienced it, or had an adequate explanation, phantom pain is a bit hard to accept. The idea that our brains are “pre-wired” in some ways helps us to understand what’s going on when an amputee feels sensations in a limb that has been removed.

Pre-wiring isn’t limited to the physical realm, though. We humans have a pre-wired sense of justice. Even very young children are able to recognize when they have been “wronged” in some ways. Cultural conditioning certainly plays a significant role in defining that sense of justice, but the sense is there however it is conditioned.

There is a reason why we can tell when others have perpetrated an injustice against us. It’s the same reason that we can sometimes recognize when we’ve treated others unfairly. We have a moral sense. We have a more or less clear concept of right and wrong.

Even in western society, with its emphasis on tolerance, there are some things about which intolerance is not only tolerated, but applauded. Quite simply, human beings are moral creatures. We know about right and wrong. We know about good and bad. There is a difference, and societies count on social consensus about these things to maintain law and order.

In the spiritual realm, morality is supremely important because it is there that the foundation is laid for our attitudes, affections, and actions. Spiritual deterioration will eventually work its way out in pride and self-service, expressed in more or less nasty ways. Spiritual regeneration expresses itself in humility and other-centeredness among other ways. We can be thankful that there is a way to halt the process of decline and begin moving toward spiritual life - what is “good” and “right” as God intended.

David Humphreys and Ron Hughes
© August 2004