A study appearing in the journal NeuroImage (2001;14:60-66) looked at the effect acupuncture has on a PET scan. A positron emission tomography (PET) scan is an imaging test that shows how the organs and tissues inside the body are actually functioning. It can measure such vital functions as blood flow, oxygen use, and glucose metabolism. It measures metabolic changes happening on a cellular level. In a PET scan, the subject is injected with a radiotracer (a small dose of a radioactive chemical). The scanner detects and records the energy given off by the tracer substance and creates computerized images of the body.

In this study, 13 subjects between the ages of 21 and 32 were given PET scans before and after (25 minutes after treatment) acupuncture treatment. Activation could be seen in areas of the brain that are involved with chronic pain (the left anterior cingulus, the insulae bilaterally, the cerebellum bilaterally, the left superior frontal gyrus, and the right medial and inferior frontal gyri).