One day, eliminating pain may just be a matter of flicking on a light. Scientists have shown that you can implant LEDs that stop neurons from firing and cut out pain reception. The current technique (tested in mice) requires altering the neurons' DNA -- you couldn't just stick them in anyone. They're soft, however, and safe enough that you can leave them under the skin for long periods of time without limiting motion or wrecking tissue.
If researchers can get this method working with unmodified human neurons, the implications would be huge for medicine. Chronic pain sufferers could switch off pain in specific areas, rather than resorting to drugs that may affect more of the body or carry their share of side effects. And you could shut it off when necessary, such as during a doctor's check-up -- you could find out whether or not you're recovering without removing the implants altogether.
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