The Scientific Basis Of Acupuncture Pathways
Stimulation of a nerve with an acupuncture needle activates that nerve, inducing changes consistent with its motor, sensory or autonomic nature.
We’ve all seen them—acupuncture models with dots and lines that represent so-called "points” and "meridians.” Do these structures exist? Does it matter? Yes, and yes, despite skeptics’ strong disavowal of their presence.1 2
Contrary to the popular notion that these lines trace out "energy” pathways just beneath the skin, the linear channels correspond to deeper nerves, vessels and myofascial cleavage planes.
In that structure dictates function, stimulation of a nerve with an acupuncture needle, electrical stimulus or laser beam activates that nerve, inducing changes consistent with its motor, sensory or autonomic nature. Some peripheral nerves link to brainstem centers that participate in the restoration and control of homeostasis.
Knowledge of the neural networks connected to acupuncture loci gives the science-based practitioner insight into what physiologic outcomes to anticipate.
For example, acupuncture stimulation of neural targets near the carotid body invokes reduction of blood pressure.
Activation of afferent fibers near the median nerve helps restore nerve function in cases of compression as in carpal tunnel syndrome, but it also helps regulate blood pressure and reduce arrhythmias due to connections between the median nerve and rostral ventrolateral medulla, a site of somatoautonomic convergence that regulates cardiopulmonary activity.
These types of scientific explanations for the effects of acupuncture differ starkly from those of traditional Chinese medicine (TCM) practitioners who talk about moving wind and driving out evil energy.
How can veterinarians and physicians who share a common background in veterinary or medical school practice from such widely disparate standpoints? Much has to do with the educational program they choose to pursue, whether TCM or medical acupuncture.
History helps explain the source of the divide, and much focuses on the source of the terms "meridian” and "channel.”
While "channel” connotes the original anatomic basis of the acupuncture pathways as blood vessel and nerve pathways, the term "meridian” arose in the early 20th century.
At this time, a French bank clerk, Georges Soulie de Morant, was working in China and became fascinated by Chinese medicine and culture. He translated acupuncture texts and other representations of Chinese culture into French to make them accessible to Western audiences.
However, his own agenda to promote acupuncture as energy mysticism interfered with the accuracy of his selection of terms.
With no background in biologically based medicine, Soulie de Morant claimed that Chinese medicine did not involve actual anatomy and physiology, but something ethereal and intangible.3 Instead of translating "Qi” into "circulating gases” coursing throughout the vasculature as would have been appropriate, Soulie de Morant selected the term "energy” for Qi, apologizing that he was at "lack of a better word.”
Thus began the decades leading up to the present, of misplaced beliefs about acupuncture as "energy medicine.” Had this not happened, acupuncture could have avoided this metaphysical detour.
Hundreds of years earlier, in 1683 a Dutch physician working for the Dutch East India Company, Willem ten Rhijne, came into regular contact with Chinese and Japanese acupuncturists.
He sought explanations for the dots and lines drawn on the body directly from the source and learned that the pathways constituted nothing more than access points for nerves and vessels.
Then in the 1930s came Soulie de Morant, who set acupuncture on a course of mysticism and abstractions from which it is only now beginning to recover, with the help of scientific insights.
How did Soulie de Morant succeed in derailing what simply amounts to afferent nerve stimulation?
He did so through a series of mistranslations; how deliberate as opposed to misguided these misrepresentations were remains unclear. As the most telling example, he selected the term "meridian” to describe what the Chinese referred to as blood vessels ("jing,” "luo,” and "mai”).
The Chinese term for "meridian” is actually "jingxian,” which was not an acupuncture term until Soulie de Morant. To him, the long black lines that crossed back and forth over the body in acupuncture atlases likely resembled the invisible lines of longitude and latitude drawn on maps and globes. Conveniently for Soulie de Morant, perhaps, meridians of the planet are no more tangible than those he described on the body, entirely ignoring the channels’ neurovascular basis.
What have these translation missteps wrought that affect us today?
Postgraduate programs in TCM spend large amounts of class time describing how "energy” moves around the body. French approaches such as "acupuncture energetics” maintain Soulie de Morant’s premise of energy-based medicine.
As an example, this sort of instruction describes the function of an additional eight "curious” or "extraordinary” meridians that serve as energy reservoirs for the 12 paired "principal meridians.”
One is expected to accept that these eight invisible pathways feed the others energy when they run low or accept overflow in times of plenty.
If only everyone would realize that the ancient Chinese acupuncturists were actually referring to real vessels, i.e., the capacitance system of the vena cava and associated veins, those learning acupuncture could encounter a realistic, intricate and anatomically based system that describes the true substance of the acupuncture channels in depth.4
Once one knows the structure of acupuncture, understanding the physiology follows naturally, providing a means by which to practice in alignment with modern medicine instead of perpetual folklore.
Anatomic and physiologic investigations confirm the presence of a variety of afferent endings at acupuncture points, capable of ferrying somatoautonomic input to peripheral nerves, associated spinal cord segments and brain regions.
These neural centers process the incoming signals and adjust endogenous regulation that results in improved circulation and organ function, analgesia, muscle relaxation, and normalized immune function, among other effects.
A medical acupuncturist studies these actual connections and selects sites according to the desired neuromodulatory outcomes. Medical researchers and physiologists are now in agreement that the peripheral and central nervous systems constitute the "most rational basis for defining meridians.”5 6
Is it not time, then, for TCM teachers, especially those who teach at AVMA-accredited institutions and national veterinary meetings, to reconsider claiming that Evil Qi causes illness?7
Is it not, then, reasonable to expect that organizations pursuing specialty recognition of acupuncture by the American Board of Medical Specialties8 should divorce themselves from energy-based imaginings and instead adopt scientific perspectives?
Is it not time for TCM-based veterinarians to avoid claiming that they can diagnose equine herpes and equine protozoal myelitis based on meridian palpation9, considering research to the contrary?10 Or have belief systems grown so strong that they trump the need for rational explanations and research justification?
In other words, is science completely irrelevant to TCM?11
Ramey DW. Acupuncture points and meridians do not exist. The Scientific Review of Alternative Medicine. 2001;5(3):143-138.
2 The SkeptVet blog. Veterinary acupuncture. Accessed at http://www.skeptvet.com on 07-14-13.
3 Kendall DE. Problems with the energy-meridian theory. Accessed at http://www.pacificcollege.edu on 07-14-13.
4 Kendall DE. Energy-meridian misconceptions of Chinese Medicine. Accessed at http://www.tedpriebe.com on 07-14-13.
5 Litscher G. Letter to the editor. No, there is no conclusive scientific evidence for visualization of meridians at the moment. J Alt Complement Med. 2013; [Epub ahead of print].
6 Longhurst JC. Defining meridians: a modern basis of understanding. J Acupunct Meridian Stud. 2010;3(2):67-74.
7 Xie, H and Shmalberg, J. Small animal and exotics. Proceedings of the North American Veterinary Conference, Orlando, Florida, USA, 17-21 January, 2009; Gainesville:The North American Veterinary Conference,2009,84-86(Conference paper)
8 American Academy of Veterinary Acupuncture website. Accessed at http://www.aava.org on 07-14-13.
9 Anonymous. EPM: Elusive, pernicious, manageable. Holistic Horse. Accessed at http://holistichorse.com on 07-14-13.
10 Chvala S, Nowotny N, Kotzab E, et al. Use of the meridian test for the detection of equine herpesvirus type 1 infection in horses with decreased performance. J Am Vet Med Assoc. 2004;225:554-559.
11 Cain M, Escodro PB, Luna SPL, et al. Equine protozoal myeloencephalitis: how predictable is the diagnosis with acupressure? 29th International Congress on Veterinary Acupuncture proceedings. Pp. 315-319. Accessed at http://www.ivas.org on 07-14-13.
Dr. Robinson, Dipl. ABMA, FAAMA, oversees complementary veterinary education at Colorado State University.