Instead of a pill, the physicians of the future may be prescribing LED implants to relieve their patients' pain. 

A team of researchers from Washington University in St. Louis and the University of Illinois at Urbana Champaign recently demonstrated how their device could be used to manipulate the neural circuits associated with pain in mice. As they explained in a research letter to Nature Biotechnology, in order for the technique to work, the scientists tweaked the mice's DNA so their neurons could be made to fire, or could be stopped from firing, in response to the light, as MIT Technology Review explains. Not only were the wireless light-emitting diode (LED) implants effective, they also left no evidence of tissue damage or motor-function impairment in their subjects.

Scientists have looked into the technology, called optogenetics, as a treatment for pain in the past. Previous versions used external light sources that had to be attached to a part of the skeleton, limiting the circuits they were targeting to those near the skull. This latest device is made from thin, flexible material that can be implanted in a mouse’s (or, in theory, a person’s) delicate neural tissue without damaging it. Not only could this be used to treat pain more thoroughly, it could help researchers get a more solid grasp on the chronic pain that originates from neurons in the peripheral nervous system and spinal cord. The causes of chronic pain still largely remain a mystery, so gaining greater understanding is the first step toward developing better treatments. 

[h/t: MIT Technology Review]