When the brain gets incomplete signals from its peripheral nerves, it does its best job to "fill in the gaps" with its best guess of what that information should be.

Unfortunately, this mechanism can lead to symptoms like phantom pain or itching. As the author puts it, sometimes the check engine light is really nothing wrong with the engine but a faulty light itself.

One promising solution to these medical problems is to fill in the missing data in a different way. For example, phantom limb sufferers can look in a mirror image of their good limb, pretend it's their missing limb, and feel immediate and lasting relief. This may help with things like phantom itching, too.

I don't think there's an easy tldr. The lead character is a woman with a number of maladies, but develops an itch that had no apparent physical manifestation and shouldn't have been possible as the nerve endings in the itchy location were dead. The article is a sprawling overview of the history of diagnosing not just itches, but understanding the cause of such phenomenon as "phantom limbs"

woman has itchy scalp, no doctor can figure out how to cure it, article ends with "maybe the same mirror box therapy that is used to treat phantom limb pain will work" - no follow up if it was attempted or if it worked. All-in-all pretty shit article and I'm not sure what it's doing here.

It's worth the read. Like a drama/horror/science journal blend.