The Itch
I have this more or less permanent itch. It's located on my back just to the spine side of my right shoulder blade in a spot that I cannot reach with my fingers of either hand. Many, if not most of you have seen me seek relief by scratching my back on the sharp corner of a door or wall. The back of my tee-shirts often have a brown spot on them corresponding to the itch from rubbing my back on the bark of a tree which provides the most satisfactory relief of anything I've found save the CFO's fingernails. With scratching, the itch may go away for a few hours or even a few days. But, without fail, it will return.
Now the problem with this itch is that there are no apparent causes for it. The CFO always reports that there is nothing there to indicate when to scratch. Yet, when she finds the spot, relief is instant. Further, she tells me the spot moves around in the same general area from one itch to the next.
I have reported this itch to my quack who also says that he can see nothing in the area except for scratch marks. He recommended a lotion containing a bit of hydrocortisone. That, of course, provided no relief at all.
I have tried changing soaps and shampoos. I've scrubbed the area with a long-handled brush while showering. Nothing.
The latest issue of New Yorker magazine arrived on Friday containing a article by Atul Gawande, surgeon and professor at Harvard Medical School, on, of all things, itching.
Seems that itching is a sensation initiated by special "itch" nerves to produce a scratching reaction. In dogs, for example, the scratch gets rid of the flea stimulating the itch nerves.
Now the problem in humans is that our sensations are partially what our nerves sense at the moment and partially what our brain adds to what they have just sensed based on past experience. For example when our eyes sense the alternating and disconnected patterns of light produced by a dog running behind a picket fence, it's our brain using what it has learned in the past about dogs and picket fences and motion to complete the picture and figure out that what's before us is (a) a dog, (b) a fence (c) a dog behind the fence and (d) a dog running behind a picket fence as opposed to a picket fence running in front of a dog. (What is moving can be a tricky thing. Who has not been sitting in a car at rest and suddenly gotten the sensation that the car is moving backwards when, in fact, an adjacent cars has moved forward instead? I've nearly broken a number of brake petals trying to get the car to stop going backwards!)
Once the brain has stored such sensory information it's pretty much there forever. That's why amputees can still "feel" their missing limbs when the brain receives a pattern of sensations that the brain interprets as being in the missing limb.
Further, we can sometimes stimulate the brain to "feel" sensations just thinking about them. Chances are good that you have already scratched yourself a number of times from just reading about itching and scratching!
My itch, it seems, is indeed not caused a rash or any such thing on my shoulder that normally causes an itch but rather by some other stimulus that my brain interprets as an itch. And, sure enough, a nice scratch in the area where the brain thinks it is located will make it go away for a period of time because of the itch-scratch response, only to return when the brain is once again fooled by the misinterpreted stimulus. Unfortunately, there is no known way to cause the brain to "unlearn" this itch-scratch response. So, I will continue to scratch my imaginary itch and I'll have to be content that I now just know why.
My case is a mere irritant. The story in New Yorker tells of a lady who has an imaginary itch on the side of her head that actually caused her to scratch through her scalp and scull, and into her brain, while sleeping. At the height of her despair she spent several years in a mental hospital because they had beds that could constrain her arms at night.
Gotta go. I fell the urge to scratch.
Now the problem with this itch is that there are no apparent causes for it. The CFO always reports that there is nothing there to indicate when to scratch. Yet, when she finds the spot, relief is instant. Further, she tells me the spot moves around in the same general area from one itch to the next.
I have reported this itch to my quack who also says that he can see nothing in the area except for scratch marks. He recommended a lotion containing a bit of hydrocortisone. That, of course, provided no relief at all.
I have tried changing soaps and shampoos. I've scrubbed the area with a long-handled brush while showering. Nothing.
The latest issue of New Yorker magazine arrived on Friday containing a article by Atul Gawande, surgeon and professor at Harvard Medical School, on, of all things, itching.
Seems that itching is a sensation initiated by special "itch" nerves to produce a scratching reaction. In dogs, for example, the scratch gets rid of the flea stimulating the itch nerves.
Now the problem in humans is that our sensations are partially what our nerves sense at the moment and partially what our brain adds to what they have just sensed based on past experience. For example when our eyes sense the alternating and disconnected patterns of light produced by a dog running behind a picket fence, it's our brain using what it has learned in the past about dogs and picket fences and motion to complete the picture and figure out that what's before us is (a) a dog, (b) a fence (c) a dog behind the fence and (d) a dog running behind a picket fence as opposed to a picket fence running in front of a dog. (What is moving can be a tricky thing. Who has not been sitting in a car at rest and suddenly gotten the sensation that the car is moving backwards when, in fact, an adjacent cars has moved forward instead? I've nearly broken a number of brake petals trying to get the car to stop going backwards!)
Once the brain has stored such sensory information it's pretty much there forever. That's why amputees can still "feel" their missing limbs when the brain receives a pattern of sensations that the brain interprets as being in the missing limb.
Further, we can sometimes stimulate the brain to "feel" sensations just thinking about them. Chances are good that you have already scratched yourself a number of times from just reading about itching and scratching!
My itch, it seems, is indeed not caused a rash or any such thing on my shoulder that normally causes an itch but rather by some other stimulus that my brain interprets as an itch. And, sure enough, a nice scratch in the area where the brain thinks it is located will make it go away for a period of time because of the itch-scratch response, only to return when the brain is once again fooled by the misinterpreted stimulus. Unfortunately, there is no known way to cause the brain to "unlearn" this itch-scratch response. So, I will continue to scratch my imaginary itch and I'll have to be content that I now just know why.
My case is a mere irritant. The story in New Yorker tells of a lady who has an imaginary itch on the side of her head that actually caused her to scratch through her scalp and scull, and into her brain, while sleeping. At the height of her despair she spent several years in a mental hospital because they had beds that could constrain her arms at night.
Gotta go. I fell the urge to scratch.
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