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  • Triss can you scratch my back? Yeah right there, yeah.

  • Down a little bit. OK. Oh, yeah, that's it. Don't stop.

  • Hey guys, Tara here with an answer to one of life's greatest mysteries,

  • why is scratching an itch always make it worse.

  • Every one of us has been bitten by a mosquito at some point.

  • It actually happened to a friend of mine last week,

  • and he ended up scratching it so hard he created an open wound,

  • the size of a dime which is disgusting.

  • But we've all been there , well some of us.

  • Most of us get a bug bite, we scratch it for a while and then in a few days it goes way,

  • and we never think about it again.

  • But believe it or not there are millions of people out there who suffer from chronic itching.

  • Conditions like eczema and even cancer or kidney failure can worsen it,

  • and in many cases it can have a serious impact on someone's life.

  • Well, it boils down to serotonin.

  • Serotonin is a neurotransmitter that regulates tons of different functions in your body.

  • Your mood, your memory, your sleep, your appetite, even blood clotting.

  • It produces feelings about happiness and well-being but it also controls pain,

  • and that's where the itching part comes in.

  • Chu France Chen, as a researcher at Washington University,

  • and he's been conducting studies over the years to see what produces the urge to itch.

  • His most recent one involved mice who were genetically engineered to produce no serotonin.

  • And he found that when those mice were injected with a chemical to induce itching,

  • they had almost no urge to scratch.

  • Meaning that the urge to scratch an itch begins as soon as serotonin leaves your brain and reaches the irritated spot,

  • so whenever we scratch an itch we're actually doing so

  • because the pain of scratching temporarily overrides the itchy feeling.

  • The problem is that

  • that pain causes your brain to release more serotonin

  • which intensifies the itch even more, So it's essentially a feedback loop.

  • Where you're constantly scratching harder and harder to get rid of the itchy feeling, but all you're doing is really making it even more itchy.

  • It make sense but it does bring up another interesting question.

  • Why does serotonin cause an itchy sensation to begin with?

  • Well according to Chen, it has to do with GRPR neurons

  • which are a group of brain cells known to increase itchy sensations.

  • A serotonin starts rushing to the part of your body that's irritated,

  • Its wires basically get crossed,

  • and it activates those GRPR neurons which intensifies the itch even more.

  • Chen believes that people who suffer from chronic itching could find relief

  • once a therapy is developed to block the receptor that cause the serotonin to activate those neurons.

  • Until then the best solution seems to be lots of anti-itching cream and other mittens, the softer the better.

  • My suggestion not his.

  • What do you guys think? Have you ever scratch the itch so hard that made you bleed?

  • And how did that work out for you?

  • Feel free to share your experiences with us in the comments down below.

  • And as always thank you guys for watching.

Triss can you scratch my back? Yeah right there, yeah.

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B1 US itch serotonin itching itchy scratching chen

Why Scratching An Itch Makes It Worse

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    Gisele Sung posted on 2014/11/18
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