The Mechanism of Iitch

The reason we have an itchy or a sensation of itch in the first place is almost certainly from our evolutionary origins because things that crawl and creep over your skin will be trying to get into your body as a parasite. The mechanism behind itch is that there is a population of nerve cells in the skin. They're very fine, tiny nerve fibers that run up to the spinal cord and they use a specific signaling pathway. When they become active, combined with signals about location of the skin, they tell the brain this part of the skin itches. And when you activate the pain nerves in that patch of skin, they feed back onto your spinal cord and inhibit the nerve fibers that turn on the