This study evaluates invasive deep brain stimulation (DBS) in the treatment of three types of
chronic neuropathic pain, i) Post Stroke pain syndrome ii) Phantom Limb pain and iii) Spinal
Cord Injury Pain. Participants will be implanted with recording / stimulation electrodes in
pain-related circuits of the brain. Relief of pain symptoms with stimulation will be studied
in both groups. It is hypothesized that neural signals will correlate with pain states and
that DBS can disrupt these pain states in both groups, perhaps with differences in underlying
neural mechanisms for pain relief.