Acupuncture is a millennia-old practice that originated in China, where thin needles are inserted at specific points in the body. It is commonly used to treat pain, relieve stress, and improve sleep and digestive function. But science has only relatively recently started to examine how acupuncture works.
Since the 1950s, scientific research has shown acupuncture’s effects on the peripheral nervous system, endocrine and immune systems, cardiovascular system, and digestive system. By stimulating the body’s various systems, acupuncture can help to relieve pain and promote healing. For example, endorphins, the body’s own morphine-like chemicals, are released when needles penetrate the skin. Another chemical involved in pain control, adenosine, is released in the skin during acupuncture. But does acupuncture change how the brain functions?
Recent research, published in the prestigious journal Brain, has shown how acupuncture may relieve pain in people with carpal tunnel syndrome, a painful condition caused by compression of the nerves at the wrist. Eight weeks of acupuncture improved pain and neurophysiological outcomes not only at the wrist, but also in the primary somatosensory cortex, a brain region involved in pain perception. Symptoms remained improved for at least 3 months afterwards.
This study is important as it demonstrated that true acupuncture (22corresponding to acupuncture points in Traditional Chinese Medicine) elicited neurophysiological changes, whereas sham treatment (inserting needles to non-acupuncture points) did not. It is important to note however, that sham treatment also reduces pain, despite not changing neural functioning. This may be related to local repair and healing responses where the needle is placed. For instance, acupuncture elicits anti-inflammatory effects by reducing the activity of inflammatory cells called macrophages. More scientific research is required to tease out precisely how stimulating specific acupuncture points activates the body’s own healing mechanisms.
Neuroimaging studies have also revealed that acupuncture reduces activity in brain regions that modulate emotion. Negative emotions or stress can often result in painful physical symptoms. Indeed, there is a major overlap in the neurobiological mechanisms that process pain and mood. Therefore, treating mood and stress can often result in reduced pain.
Acupuncture is a safe, effective treatment for pain, sleep and stress, among other ailments. Though a lot of new information has come to light, particularly how acupuncture can change the brain, there remains a vast chasm of unanswered questions. What we do know, however, is that the ancient wisdom of acupuncture highly complements Western medicine to counteract the effects of modern stresses and relieve our aches and pains.
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Maeda et al (2017). Rewiring the primary somatosensory cortex in carpal tunnel syndrome with acupuncture. Brain. 140, 4, 1 914–927.
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About the author
Nikita Burke (B.Sc Physiology, PhD Neuroscience) is a researcher examining the mechanisms of pain and opioids at the Hotchkiss Brain Institute, University of Calgary. She received her doctorate in neuroscience at the National University of Ireland, Galway, where she examined the role of the immune system in the link between depression and chronic pain.