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Speaker 1: Welcome to Brainstuff from house stuff works dot com where
Speaker 1: smart happens. Hi Am Marshall brand with today's question, When
Speaker 1: you have an itch, what's actually happening inside your skin?
Speaker 1: The average human body is covered by about twenty square
Speaker 1: feet or two square meters of skin, and if you
Speaker 1: think about it, skin is the only organ in the
Speaker 1: human body that's constantly exposed to potential irritation from the
Speaker 1: outside elements. With so many things coming into contact with
Speaker 1: your skin daily, you're bound to get an itch or two.
Speaker 1: Serious switching can be caused by allergies, to z s, emotions,
Speaker 1: and infections. But let's take a look at what causes
Speaker 1: the common itches that aggravate you every day. Itching, also
Speaker 1: known as puritis, starts with some kind of external stimuli,
Speaker 1: including bugs, dust, clothing fibers, and hair like tickling, Itching
Speaker 1: is a built in defense mechanism that alerts your body
Speaker 1: to the potential of being harmed. In this case, it
Speaker 1: might be the potential of being bit by a bug.
Speaker 1: When the stimuli lands on your skin, it may not
Speaker 1: bother you at first, but soon it will begin to
Speaker 1: rub back and forth across your skin. Once the hair
Speaker 1: or dust scratches your skin, surface layer receptors in the
Speaker 1: dermness of the skin will become irritated. In a split second,
Speaker 1: these receptors send a signal through fibers in the skin
Speaker 1: to your spinal cord and then up to the cerebral
Speaker 1: cortex in your brain. The same fibers that send itching
Speaker 1: signals are also used to send pain signals to the brain,
Speaker 1: which once led some scientists to believe that itching was
Speaker 1: a form of light pain. That notion has since been
Speaker 1: dispelled by research which showed that pain and itching elicit
Speaker 1: opposite responses. Pain causes us to withdraw, and itching causes
Speaker 1: us to scratch. As soon as we feel an itch,
Speaker 1: our first natural response is to scratch the spot of
Speaker 1: the itch with our fingernails. The reason for this response
Speaker 1: is simple, we want to remove the irritant as soon
Speaker 1: as possible. Once you scratch the area of irritation, you're
Speaker 1: likely to feel some relief. When your brain realizes that
Speaker 1: you've scratched away the irritant, the signal being sent to
Speaker 1: your brain that you have an itch is interrupted and
Speaker 1: therefore no longer recognized by the brain. Even if you
Speaker 1: don't remove the irritants, scratching will at least cause pain
Speaker 1: and divert your attention away from the itching. The irritant
Speaker 1: that caused the itching is very small, usually maybe only
Speaker 1: a few might runs in length, so it disturbs only
Speaker 1: a few nerve endings. When you use your fingernail to
Speaker 1: scratch the spot where the irritant is, you not only
Speaker 1: remove the irritant, but you irritate a lot more nerve
Speaker 1: endings than the irritan did. Be sure to check out
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Speaker 1: Stuff Work staff as we explore them as promising and
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