Scientists still argue about what can cause itching, how this sensation arises and what can be provoked. However, it is no secret that the study of this issue can shed light on many secrets of the human brain.
Today we have gathered for you some interesting facts that will surely puzzle you:
- The average person itches about ninety-seven times a day. Moreover, it is noteworthy that the occurrence of itching can be "psychologically contagious" - in other words, you saw that another person is itching, and some area of your skin has begun to itch.
- The most common cause of itching is toxins that remain on the skin due to interactions with animals or plants. These toxic substances cause a sharp immune response of the body, which is manifested by the release of histamines. As a result, nerve fibers begin to send their own "itchy" signals to the brain.
- For a long time it was believed that the same nerve fibers were responsible for the transmission of itching and pain. This theory was debunked in 1997 when it suddenly turned out that a separate type of nerve fibers was responsible for the "itchy" sensations.
- Human nerve fibers transmit impulses at different speeds. At the same time, signals that something is scratching with us are transmitted very slowly. So, for comparison, the speed of the touch signal is 321 km / h. In the event that you touch a hot iron, the pain will be transmitted at a speed of 128 km / h. In comparison, the desire to itch literally "creeps" like a turtle - its speed is only 3.2 km / h.
- As noted above, scratching oneself is contagious. Moreover, which is quite funny, not only in humans, but also in rodents. Scientists found this out by showing laboratory mice a video capturing how their cousins were itching. The group that attended the movie show also began to itch en masse.
- The cause of "contagious" scratching is the microscopic part of the brain called the suprachiasmatic nucleus. So far, neuroscientists have not been able to find out what is the mechanism of its action.
- Scratching is the best way to get rid of the effects of contact with toxins. Scratching dilates blood vessels, as a result of which leukocytes and plasma wash them. It is this reaction that explains the fact that the skin turns red when scratched.
- It's hard to believe, but scratching provokes the release of the "hormone of happiness" - that same serotonin. This is a special neurotransmitter, which, scientists say, allows us to feel a surge of euphoria. The higher the concentration of serotonin in our body, the more happy a person feels. That is why it is often difficult to stop itching even after completing contact with the allergen.
- The most enjoyable place to scratch is ... ankle. This is evidenced by data from studies that were published in 2012 in the British journal of dermatology. According to the results of tests carried out by dermatologists, it is on the ankle that the sensation of itching is the most intense and painful - however, it is in this area that the pleasure of scratching is also experienced most clearly and lasts as long as possible.
- It’s a paradox, but the more you scratch a certain area, the more irresistibly it itches. The thing is that when combing the skin into the blood, histamine is released, as a result of which itchy signals continue to enter the brain.
- Despite the fact that scratching brings pleasure, people who suffer from psoriasis or eczema, it is strictly forbidden to violate the integrity of the skin. Therefore, such patients often have to take antihistamines, which help reduce the intensity of itching.
- Chronic itching can be just as painful as chronic pain. According to scientists, patients who experience constant itching suffer from the same level of discomfort as people with a variety of diseases of a chronic nature. Thus, as noted in a material published by Archives of Dermatology, chronic itching can be considered an analogue of pain - only skin.
- That is why in the event that the itching is causeless and prolonged, you should consult a doctor - it can be a manifestation of a number of serious diseases, including cancer.