What makes scratching an itch worse?

Why does scratching an itch always seem to make it worse? That's one of life's greatest mysteries. Millions of people suffer from chronic itching. And almost everyone can relate to the temporarry relief itching can produce.

But why does itching always seem to make it worse, when it feels so good in the moment? The explanation may leave you scratching you head.

A futile feedback loop in your brain triggered by the hormone serotonin is to blame. Watch the video for the full details.

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