Poor little fellows. These behaviours mirror those seen in chronic itch disorder, which affects about 8. The new research also suggests that, if the results from the study also apply to humans, chronic itch disorder may be caused by a specific deficiency in these special spinal cells. This may lead to targeted treatments to help people suffering with this disorder in the future. The researchers also revealed that while itching caused by light touch on the hairy skin was disrupted in the mice, there was no change in the way they responded to itches that caused an inflammatory response, for example one caused by a mosquito bite.
Why is this interesting? Because even though both kinds of itch feel subjectively the same to you, your body is sending specific information about the kind of itch is occurring to your brain, via completely distinct pathways. The mice also showed completely normal responses to touch-induced pain.
Interestingly, previous research has shown that there is a complicated relationship between chemical itch from things like insect bites and pain. It turns out that a painful touch or heat sensation can actually suppress the feeling of a chemical itch not that this seems like a particularly good trade-off.
It is for this reason that it feels so good to scratch at a rash — because it is the pain of scratching that actually relieves the itch.
Unfortunately, the effect is all too temporary. Surprisingly, there is some evidence to suggest it is not only occurrences on your skin that can cause itch and there may be a psychological element. For You Children Patient Handouts. What is itching? What causes itching? Itching is a symptom of many health conditions. Some common causes are Allergic reactions to food , insect bites , pollen , and medicines Skin conditions such as eczema , psoriasis , and dry skin Irritating chemicals, cosmetics , and other substances Parasites such as pinworms , scabies , head and body lice Pregnancy Liver , kidney , or thyroid diseases Certain cancers or cancer treatments Diseases that can affect the nervous system, such as diabetes and shingles What are the treatments for itching?
Most itching is not serious. To feel better, you could try Applying cold compresses Using moisturizing lotions Taking lukewarm or oatmeal baths Using over-the-counter hydrocortisone cream or antihistamines Avoiding scratching, wearing irritating fabrics, and exposure to high heat and humidity Contact your health care provider if your itching is severe, does not go away after a few weeks, or does not have an apparent cause.
Start Here. Related Issues. Statistics and Research. While it can be a nuisance, pruritus serves as an important sensory and self-protective mechanism, as do other skin sensations such as touch, pain, vibration, cold and heat. It can alert us to harmful external agents, but can become unbearable if not treated. Pruritus is a dominant symptom of many skin diseases and also occurs in some diseases that affect the entire body.
An itching sensation of the skin arises due to stimulation of pruriceptors—itch-sensing nerve endings—by mechanical, thermal or chemical mediators. These include:. Stimulation by any of these agents is typically related to inflammation, dryness or other damage to the skin, mucous membranes or conjunctiva of the eye. In general, pruritus involves activation of the pruriceptors of specialized nerve cells called C-fibers. These C-fibers are identical to those associated with the sensation of pain, but they are functionally distinct and only convey the itch sensation—they comprise about 5 percent of the total C-fibers in human skin.
When stimulated superficially on the skin, these C-fibers carry signals along the nerve to the spinal cord and on to the brain, where they are processed, generating a scratching or rubbing reflex response. Scratching and rubbing then interfere with the sensations arising from pruriceptors by stimulating various pain and touch receptors in the same areas.
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