Three floors below Dmitriy Sheyn’s lab at Cedars-Sinai Medical Center, doctors remove degenerated intervertebral discs from patients with severe back pain. Instead of tossing the old discs, however, ...

Most people think about pain as a simple cause-and-effect process. For example, if you touch a hot stove, you probably assume that the nerves in the skin feel how hot the stove is and signals are sent ...