" Moskowitz defined chronic pain as “learned pain.” Chronic pain not only indicates illness; it is itself an illness. The body’s alarm system is stuck in the “on” position, because the person has been unable to remedy the cause of an acute pain, and the central nervous system has become damaged. "

― Norman Doidge , The Brain's Way of Healing: Remarkable Discoveries and Recoveries from the Frontiers of Neuroplasticity