Originating in ancient China, acupuncture has been used for 2500 years. Traditional Chinese medicine holds that disease is caused by blockages and imbalances of energy (known as chi) flowing through meridians in the body, and can be eased by inserting needles at specific points.
Since the 1970s, acupuncture has become more popular outside east Asia. Once widely considered a quack medicine, there is now tentative support for its use in certain conditions from respected official bodies such as the World Health Organization, the National Health Service in the UK and the National Institutes of Health in the US.
There is evidence that acupuncture is effective in treating a range of conditions including spinal injuries, infertility and the side effects of chemotherapy, and that its effects aren't entirely due to the placebo effect. However, despite extensive research, the mechanism of this ancient healing art remains unknown.
Wenjing Huang of Charité University Medical Center, Berlin, Germany, and colleagues used more than 100 studies to produce these brain maps of 18 acupuncture points. Areas of the brain activated by stimulating a point are shown in red; areas deactivated are shown in blue.
For example, the two vision-related points GB37 (gall bladder) and UB60 (urinary bladder) showed deactivation in visual brain areas like the cuneus. The team concluded that acupuncture seems to affect the brain's processing of both physical sensations and thought. For now, though, the source of our chi remains elusive.
Journal reference: PLoS One, DOI: 10.1371/journal.pone.0032960
Images: Huang and colleagues, PLoS