The brain has a switch that shuts off chronic pain

Scientists have identified a switch in mice brains that shuts off chronic pain.

Deep at the base of the brain, a tiny cluster of nerve cells serves as the body’s natural pain reliever, dialing down pain signals traveling up the spinal cord. But nerve damage can flip this system into a hyperactive engine for chronic pain.

Now, researchers at Washington University School of Medicine in St. Louis have figured out why that switch f...