A female acupuncturist inserts acupuncture needles on the back of a female patient. Derived from traditional Chinese medicine, acupuncture involves insertion of fine metal needles at specified points deep under the skin. The needles are then either vibrated, heated, or may have a small electric current applied. The point of insertion is governed by the symptom. It is thought that the needle activates sensory nerves thus promoting the brain to produce endorphins (natural analgesics). In western culture, acupuncture is increasingly used in complementary medicine for relief of pain or the withdrawal symptoms of addiction.