Dr. Atul Gawande (Erik Jacobs for The New York Times)

“Itching is a most peculiar and diabolical sensation,'’ writes surgeon and author Dr. Atul Gawande in the current issue of The New Yorker. “Itch has been ranked, by scientific and artistic observers alike, among the most distressing physical sensations one can experience.'’

After reading Dr. Gawande’s latest essay, “The Itch,” you will certainly agree, and you may find yourself experiencing irksome itches all over your body. Dr. Gawande’s exploration of itching, and what it says about the brain and body, is told through the shocking story of Patient M., who is tortured by an incessant itch. He writes:

“Scratching is one of the sweetest gratifications of nature, and as ready at hand as any,” wrote 16th-century French philosopher Michel de Montaigne. “But repentance follows too annoyingly close at its heels.” For M., certainly, it did: the itching was so torturous, and the area so numb, that her scratching began to go through the skin. At a later office visit, her doctor found a silver-dollar-size patch of scalp where skin had been replaced by scab. M. tried bandaging her head, wearing caps to bed. But her fingernails would always find a way to her flesh, especially while she slept.

We also learn more about the sensation of itching.

Though scratching can provide momentary relief, it often makes the itching worse. Dermatologists call this the itch-scratch cycle. Scientists believe that itch, and the accompanying scratch reflex, evolved in order to protect us from insects and clinging plant toxins — from such dangers as malaria, yellow fever, and dengue, transmitted by mosquitoes; from tularemia, river blindness, and sleeping sickness, transmitted by flies; from typhus-bearing lice, plague-bearing fleas, and poisonous spiders. The theory goes a long way toward explaining why itch is so exquisitely tuned. You can spend all day without noticing the feel of your shirt collar on your neck, and yet a single stray thread poking out, or a louse’s fine legs brushing by, can set you scratching furiously.

There aren’t many medical stories that make me gasp out loud, but this one did. It’s a must-read. (from NYTimes blog)