New research shows that acupuncture at acupoint GV20 (DU20, Hundred Meetings, Baihui) increases blow flow to the brain without raising arterial blood pressure or pulse rate. The researchers sought to measure cerebral blow flow in an attempt to understand the mechanisms by which acupuncture induces a therapeutic effect. GV20 is well regarded for it ability to treat disorders related to the head and brain. Indications for the use of GV20 include dizziness, hypertension, hypotension, deficient memory, ear ringing (tinnitus), headaches, diminished vision, windstroke, and syncope.

The researches measured increases in the blood flow velocity of the middle cerebral artery (MCA) and anterior cerebral artery (ACA) during acupuncture needling of GV20. Although blood flow increased, blood pressure and pulse rate did not change significantly. The researchers conclude, "The data suggest that GV20 acupuncture treatment increases cerebral blood flow. The results of this small-scale study provide preliminary evidence for acupuncture effectiveness."

GV20 is located near the top of the head. According to Chinese medicine theory, GV20 (Governing Vessel 20) is the Meeting point of the GV channel with the Urination Bladder, Gallbladder, Sanjiao (Triple Burner), and Liver channels. GV20 is a Sea of Marrow Point. It calms the wind, descends the uprising Yang, lifts the fallen Yang, nourishes the sea of marrow (brain), and calms the Shen (spirit). From a more western perspective, the researchers have measured the physical effects of GV20 on blood flow to the brain thereby showing one mechanism by which GV20 nourishes the sea of marrow (brain). This also demonstrates physiological changes in the body when GV20 is used to eliminate headaches.

Reference:
Hyung-sik Byeon, Sang-kwan Moon, Seong-uk Park, Woo-sang Jung, Jung-mi Park, Chang-nam Ko, Ki-ho Cho, Young-suk Kim and Hyung-sup Bae. The Journal of Alternative and Complementary Medicine. March 2011, 17(3): 219-224.