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

  • - Down a little bit. - OK. - Yeah. 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 Fang 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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