others change the way the brain receives the messages, reducing their effect. Many methods of controlling chronic pain without drugs have been developed. These include hypnosis, acupuncture. Massage, and electronic stimulation of nerves. Pain sometimes works in strange ways. It is possible, for example, to suffer a serious injury but not feel any pain- soldiers in the battle may not feel pain from wounds until after the battle. The opposite can happen too- patients who lose a limb can continue to feel pain in the limb long afterwards even though it is missing. This phantom limb' pain is an example of neuropathic pain, caused by damage to the remaining nerves.