As scientists have discovered, some of the nerves responsible for sensation of itching, but at the same time they do not find pain. This scientific discovery was published in Nature Neuroscience and aroused long discussions on the topic of that itching is a special manifestation of pain.
Today, scientists available technology "suppression" of these nerve endings using effective drugs to combat the itching.
For quite a long time, the cause and source of the itching remained a mystery. Some nerves filed a response to the stimulation of itching, but it did not give the opportunity to identify nerve fibers, which caused the desire to scratch.
In some time, scientists believed that the itching and pain "answer" the same nerves, only perceived by the brain they are different.
Recently opened nerves, which causes the desire to scratch, are in the spine, next to the spinal cord. This explains the fact that people have a desire to scratch the outer skin, while they do not feel itching in the internal organs.