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Acupuncture regulates brain regions for ischemic stroke patients. Southern Medical University researchers gathered MRI data in a controlled clinical trial consisting of both healthy subjects and patients suffering from ischemic stroke. In a controlled human clinical trial, Waiguan (TB5) applied unilaterally to the right arm produced significant MRI findings. True acupuncture caused important changes in brain functional connectivity.
The researchers determined that true acupuncture triggers significant negative activation in the default mode network (DMN) and other brain regions specific to the Traditional Chinese Medicine (TCM) indications of Waiguan. The DMN is a network of highly correlated brain regions, which is active under resting-state conditions. In addition, they found that ischemic stroke affects the brain’s overall response to acupuncture. The healthy control group and the ischemic stroke group had different negatively-activated brain regions in the DMN when receiving true acupuncture. 
The earliest introduction of Waiguan was found in the Huangdi Neijing (The Yellow Emperor’s Classic of Medicine). Waiguan is the luo-connecting point of the hand shaoyang sanjiao meridian as well as one of the eight confluent points. It is the confluent point of the yang linking vessel. Needling Waiguan is indicated for the treatment of the following disorders: upper limb disorders (e.g., upper limb paralysis, pain, numbness, swelling and other motor and sensory dysfunction), head and sensory organ disorders (e.g., migraines, red and swollen eyes, tinnitus, deafness), fever and exogenous diseases (e.g., common cold, febrile illnesses). The researchers found that needling Waiguan raises negative activation in the somatic motor cortex, somatic sensory cortex, visual information processing cortex, and auditory information process cortex.
In the normal control group, the brain regions deactivated by real acupuncture included the left superior parietal lobule, left inferior parietal lobule, left precuneus, left superior frontal gyrus, left precentral gyrus, left postcentral gyrus, left occipital lobe, right precentral gyrus, right postcentral gyrus, right precuneus, and right cuneus. The precentral gyrus and superior frontal gyrus are involved in somatic motor functions. The superior parietal lobule and postcentral gyrus are associated with somatic sensory functions. The occipital lobe interprets visual information. The aforementioned regions are specific to the indications of Waiguan. The inferior parietal lobule, occipital lobe, and precuneus are DMN related regions. On the other hand, the brain regions deactivated by sham acupuncture included the left precentral gyrus, left postcentral gyrus, and right superior frontal gyrus. The results indicate specific brain activation patterns associated with true acupuncture and sham acupuncture respectively.
In the ischemic stroke group, the brain regions deactivated by real acupuncture included the left medial frontal gyrus, left postcentral gyrus, left middle temporal gyrus, right postcentral gyrus, right precentral gyrus, and right medial frontal gyrus. The middle temporal gyrus is associated with interpreting auditory information. It is regarded as a Waiguan indication-specific region along with the precentral gyrus, postcentral gyrus, and middle temporal gyrus. The medial frontal gyrus is a part of DMN regions. By contrast, the brain regions deactivated by sham acupuncture included the left and right precuneus.
The researchers (Zhang et al.) used the following study design. A total of 44 subjects participated in the study and were divided into two groups, with 24 and 20 subjects in each group respectively. The treatment group subjects were selected from the Nanfang Hospital and the First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine. The treatment group patients were diagnosed with ischemic stroke. The control group subjects included healthy volunteers.
The statistical breakdown for each group was as follows. The treatment group was comprised of 10 males and 10 females. The mean age of the treatment group was 52.8 years. The mean weight was 50.3 kg. The mean height was 160.3 cm. The mean course of disease was 2.2 months. The control group was comprised of 12 males and 12 females. The mean age of the control group was 24.6±3.4 years. The mean weight was 51.4 kg. The mean height was 163.4 cm. There were no significant differences in terms of their gender, age, height, and weight. Both groups were scanned using fMRIs after receiving true or sham acupuncture intervention.
True acupuncture and sham acupuncture were performed by the same acupuncturist with clinical and research experience. Both procedures employed the use of a tube-guided device that can be attached to the skin (Park Sham Tube, AcuPrime). The Park Sham Tube needle is a research device that mimics true acupuncture; however, the needle never penetrates the skin. Instead, the needle retracts into the handle when tapped, thereby visibly appearing as true acupuncture.
After disinfection of the acupoint site, a 0.30 × 40 mm disposable filiform needle was tapped into the acupoint of each patient with a high needle entry speed, reaching a depth of 10 (±2) mm. Upon a deqi sensation, the Ping Bu Ping Xie (attenuating and tonifying) manipulation technique was applied, with a twisting range of 180 degrees and frequency of 60 times/minute. The manipulation was not employed for the first 30 seconds, it was then initiated for the second 30 seconds, and then stopped again for the third 30 second interval. The whole process was repeated continuously for a total of 180 seconds. The device was placed on the skin until the treatment session was finished.
Sham Acupuncture Treatment Simulation
The sham acupuncture group use needles with a retractable, flattened needle point. The Ping Bu Ping Xie (attenuating and tonifying) manipulation was applied. For the first 30 seconds, the needle was slightly lifted to keep the needle point away from the skin; for the second 30 seconds, the needle was tapped into the tube to make the needle point slightly touch the skin, for the third 30 seconds, the needle was lifted again. The whole process was repeated continuously for a total of 180 seconds. The device was placed on the skin until the treatment session was finished.
According to the research, true acupuncture at Waiguan regulates DMN brain regions and raises negative activation in indication-specific regions, including the somatic motor cortex, somatic sensory cortex, visual information processing cortex, and auditory information process cortex. The process was verified by repeated applications across multiple subjects and was verified by MRIs. The results indicate that acupuncture produces point-specific effects on brain regions in ischemic stroke patients.
This type of research supports additional findings by other researchers. In another investigation, Yang et al. conclude that acupuncture has the ability to “promote the proliferation and differentiation of neural stem cells in the brain… accelerate angiogenesis and inhibit apoptosis…. prevent and treat neural injuries following cerebral ischemia.”  Yang et al. add that GV20 (Baihui) and GV26 (Shuigou) regulate cells which “increase the release of nerve growth factors (NGFs) to make nerve cells survive and axons grow, synthesize neurotransmitters, (and) metabolize toxic substances….” In addition, the researchers note that needling CV24 (Chengjiang), CV4 (Guanyuan), GV26, and GV20 “inhibit excessive proliferation of the hippocampal astrocytes and promote cellular differentiation.”
Yang et al. also note that acupuncture at GV20 and GV14 (Dazhui) affect the contents and expression of signal transducers and activators of transcription (STATs). STATs are active in the Janus kinase STAT pathway and transmit information from chemical signals outside the cell, through the cell membrane, and into gene promoters on the DNA inside the cell nucleus (causing DNA transcription and cellular activity). Yang et al. note that acupuncture’s influence on STATs indicates that it activates self-protection and reduction of “apoptosis of the nerve cells in and around the ischemic focus.” This indicates that acupuncture has a neuroprotective effect for stroke patients.
 Zhang GF, Huang Y, Tang CS, Lai XS, Chen JQ. Identification of Deactivated Brain Regions by Real and Non-penetrating Sham Acupuncture Stimulation on Waiguan: An fMRI Study in Normal Versus Pathological Conditions [J]. Chinese General Practice, 2017, 20(9):1098-1103.
 Zhou-xin Yang, Peng-dian Chen, Hai-bo Yu, Wen-shu Luo, Yong-Gang Wu, Min Pi, Jun-hua Peng, Yong-feng Liu, Shao-yun Zhang, Yan-hua Gou. Research advances in treatment of cerebral ischemic injury by acupuncture of conception and governor vessels to promote nerve regeneration. Journal of Chinese Integrative Medicine, 01-2012. vol. 10, 1. Shenzhen Traditional Chinese Medicine Hospital, Guangzhou University of Chinese Medicine.