WEBVTT - When you have an itch, what's happening under your skin?

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<v Speaker 1>Welcome to Brainstuff from house stuff works dot com where

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<v Speaker 1>smart happens. Hi Am Marshall brand with today's question, When

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<v Speaker 1>you have an itch, what's actually happening inside your skin?

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<v Speaker 1>The average human body is covered by about twenty square

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<v Speaker 1>feet or two square meters of skin, and if you

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<v Speaker 1>think about it, skin is the only organ in the

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<v Speaker 1>human body that's constantly exposed to potential irritation from the

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<v Speaker 1>outside elements. With so many things coming into contact with

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<v Speaker 1>your skin daily, you're bound to get an itch or two.

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<v Speaker 1>Serious switching can be caused by allergies, to z s, emotions,

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<v Speaker 1>and infections. But let's take a look at what causes

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<v Speaker 1>the common itches that aggravate you every day. Itching, also

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<v Speaker 1>known as puritis, starts with some kind of external stimuli,

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<v Speaker 1>including bugs, dust, clothing fibers, and hair like tickling, Itching

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<v Speaker 1>is a built in defense mechanism that alerts your body

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<v Speaker 1>to the potential of being harmed. In this case, it

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<v Speaker 1>might be the potential of being bit by a bug.

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<v Speaker 1>When the stimuli lands on your skin, it may not

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<v Speaker 1>bother you at first, but soon it will begin to

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<v Speaker 1>rub back and forth across your skin. Once the hair

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<v Speaker 1>or dust scratches your skin, surface layer receptors in the

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<v Speaker 1>dermness of the skin will become irritated. In a split second,

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<v Speaker 1>these receptors send a signal through fibers in the skin

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<v Speaker 1>to your spinal cord and then up to the cerebral

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<v Speaker 1>cortex in your brain. The same fibers that send itching

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<v Speaker 1>signals are also used to send pain signals to the brain,

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<v Speaker 1>which once led some scientists to believe that itching was

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<v Speaker 1>a form of light pain. That notion has since been

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<v Speaker 1>dispelled by research which showed that pain and itching elicit

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<v Speaker 1>opposite responses. Pain causes us to withdraw, and itching causes

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<v Speaker 1>us to scratch. As soon as we feel an itch,

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<v Speaker 1>our first natural response is to scratch the spot of

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<v Speaker 1>the itch with our fingernails. The reason for this response

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<v Speaker 1>is simple, we want to remove the irritant as soon

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<v Speaker 1>as possible. Once you scratch the area of irritation, you're

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<v Speaker 1>likely to feel some relief. When your brain realizes that

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<v Speaker 1>you've scratched away the irritant, the signal being sent to

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<v Speaker 1>your brain that you have an itch is interrupted and

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<v Speaker 1>therefore no longer recognized by the brain. Even if you

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<v Speaker 1>don't remove the irritants, scratching will at least cause pain

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<v Speaker 1>and divert your attention away from the itching. The irritant

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<v Speaker 1>that caused the itching is very small, usually maybe only

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<v Speaker 1>a few might runs in length, so it disturbs only

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<v Speaker 1>a few nerve endings. When you use your fingernail to

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<v Speaker 1>scratch the spot where the irritant is, you not only

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<v Speaker 1>remove the irritant, but you irritate a lot more nerve

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<v Speaker 1>endings than the irritan did. Be sure to check out

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