Two Distinct Neural Mechanisms Underlying Acupuncture Analgesia

Abstract

Acupuncture analgesia is a traditional treatment with a long history, although it lacks scientific evidence. It is reportedly associated with the central nervous system, including various brain regions, from the cortices to the brain stem. However, it remains unclear whether the distributed regions behave as a single unit or consist of multiple sub-units playing different roles. Magnetoencephalography is a neuroimaging technique that can measure the oscillatory frequency of neural signals and brain regions. The frequency band of neural signals allows further understanding of the characteristics of the acupuncture-related neural systems. This study measured resting-state brain activity using magnetoencephalography in 21 individuals with chronic pain before and after acupuncture treatment. The subjective level of pain was assessed using a visual analog scale, and brain activity was compared to identify the brain regions and the frequencies associated with acupuncture analgesia. Here, we categorized the changes in resting-state brain activity into two groups: low-frequency oscillatory activity (<3 Hz) in the left middle occipital and right superior partial lobule and high-frequency oscillatory activity (81–120 Hz) on both sides of the prefrontal, primary sensory, and right fusiform gyri. These findings suggest that acupuncture analgesia influences two or more sub-units of the neural systems, which helps us understand the neural mechanisms underlying acupuncture analgesia.

Research trends on acupuncture for neuropathic pain: A bibliometric analysis from 1979 to 2023

“…And then the signals caused positive changes in different brain regions, which was found that a network in the brain regulated and integrated pain, including the nucleus raphe magnus, cingulate cortex, amygdala, thalamus, periaqueductal gray, caudate nucleus, arcuate nucleus, posterior parietal cortex, preoptic area, nucleus submedius, habenular nucleus, insula, prefrontal cortex, locus coeruleus, accumbens nucleus, septal area, and other brain areas. [ 12 , 26 , 27 ] In addition, by using functional magnetic resonance imaging, these changes in different brain regions is well observed and proved after acupuncture. A systematic review showed that the preventive effect of acupuncture on migraine may be achieved by regulating the visual network, default mode network, sensory motor network, frontoparietal network, limbic system, and/or descending pain modulatory system.…”

“…Although acupuncture is widely used in the treatment of pain, its analgesic mechanism remains largely unknown. So far, a plenty of studies [12,26,27] In addition, by using functional magnetic resonance imaging, these changes in different brain regions is well observed and proved after acupuncture. A systematic review showed that the preventive effect of acupuncture on migraine may be achieved by regulating the visual network, default mode network, sensory motor network, frontoparietal network, limbic system, and/or descending pain modulatory system.…”

Decreased beta‐band activity in left supramarginal gyrus reflects cognitive decline: Evidence from a large clinical dataset in patients with dementia

“…We applied source‐level analysis using the same protocol as in our previous studies to estimate regional oscillatory intensities (Kato et al, 2022 ; Shigihara, Hoshi, Poza, et al, 2020 ; Shigihara, Hoshi, Shinada, et al, 2020 ). MEG data were pre‐processed offline using MATLAB (MathWorks, MA), the software package SPM‐12 (Wellcome Trust Centre for Neuroimaging, London, UK; https://www.fil.ion.ucl.ac.uk/spm/ ), and the MEAW system ( https://www.hokuto7.or.jp/hospital/lang/english-home/meaw/ ).…”

Dorsal brain activity reflects the severity of menopausal symptoms

“…18,19 Finally, to extract the oscillatory power from regional time-series signals, power spectral density (PSD) was computed using the Blackman-Tukey approach 29 by using nonoverlapping 5-second segments. The cumulative sum of the power in each of the canonical frequency band (delta [1-3 Hz], theta [4-7 Hz], alpha1 [7-9 Hz], alpha2 [9][10][11], alpha3 [11][12][13], beta [13][14][15][16][17][18][19][20][21][22][23][24][25], and gamma [low gamma, 26-40 Hz; high gamma, 41-70 Hz])referred to as band-wise oscillatory power-was computed for use in the statistical analysis.…”

“…We previously demonstrated that MEG is sensitive to changes in brain activities associated with the menstrual cycle. 11 Other studies have demonstrated that it is also sensitive to the changes in brain activities associated with unpleasant experiences, such as pain 12 and fatigue. 13 Furthermore, most menopausal symptoms are neurological 3 (Fig.…”