This study will investigate (a) neural and immune mechanisms underlying chronic pain in PTLS by comparing a group of PTLS patients and healthy participants on brain imaging, sensory, and immune markers; and (b) assess change in pain, brain imaging (fMRI and MRS), sensory, and immune markers in response to a combination of SNRI and glutamatergic treatment for chronic pain in PTLS (Milnacipran and D-cycloserine).