Physiological and psychological explanations for the mechanism of acupuncture as a treatment for chronic pain.

Many suggestions have been made about the possible mechanism of acupuncture as an analgesic therapy. This review provides a comprehensive account of the neurological, neurohumoral and psychologically-based hypotheses put forward. Although the exact mechanism of this treatment remains unclear, it is apparent that reproducible neurological and chemical changes occur in response to acupuncture, and that these changes almost certainly modify the response to, and perception, of pain. The mechanism of chronic pain is completely understood, but within this framework we understand acupuncture as completely as most other types of analgesic treatment.