Brain Activities Responding to Acupuncture at ST36 (zusanli) in Healthy Subjects: A Systematic Review and Meta-Analysis of Task-Based fMRI Studies

Abstract

PurposeStomach 36 (ST36, zusanli) is one of the important acupoints in acupuncture. Despite clinical functional magnetic resonance imaging (fMRI) studies of ST36 acupuncture, the brain activities and the neural mechanism following acupuncture at ST36 remain unclear.MethodsLiterature searches were conducted on online databases, including MEDLINE, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure, Wanfang database, WeiPu database, and China Biology Medicine, for task-based fMRI studies of acupuncture at ST36 in healthy subjects. Brain regions activated by ST36 acupuncture were systematically evaluated and subjected to seed-based d mapping meta-analysis. Subgroup analysis was conducted on control procedures, manual acupuncture, electrical acupuncture (EA), and acupuncture-specific activations. Meta-regression analysis was performed to explore the effects of needle retention time on brain activities following ST36 acupuncture stimulation. The activated brain regions were further decoded and mapped on large-scale functional networks to further decipher the clinical relevance of acupuncturing at ST36.ResultsA total of sixteen studies, involving a total of 401 right-handed healthy participants, that satisfied the inclusion criteria were included in the present meta-analysis. Meta-analysis showed that acupuncturing on ST36 positively activates the opercular part of the right inferior frontal gyrus (IFG.R), left superior temporal gyrus (STG.L), and right median cingulate/paracingulate gyri (MCG.R) regions. Needle retention time in an acupuncture session positively correlates with the activation of the left olfactory cortex, as shown in meta-regression analysis. Subgroup analysis revealed that EA stimulation may be a source of heterogeneity in the pooled results. Functional network mappings showed that the activated areas were mapped to the auditory network and salience network. Further functional decoding analysis showed that acupuncture on ST36 was associated with pain, secondary somatosensory, sound and language processing, and mood regulation.ConclusionAcupuncture at ST36 in healthy individuals positively activates the opercular part of IFG.R, STG.L, and MCG.R. The left olfactory cortex may exhibit positive needle retention time-dependent activities. Our findings may have clinical implications for acupuncture in analgesia, language processing, and mood disorders.Systematic Review Registrationhttps://inplasy.com/inplasy-2021-12-0035.

Activation likelihood estimation identifies brain regions activated during puncturing at Hegu in healthy volunteers: A meta-analysis

“…Several previous reviews have explored the modulatory effects of acupuncture on the brain. A systematic review based on acupuncture at Zusanli in healthy volunteers showed that brain regions such as superior temporal gyrus, insula, and postcentral gyrus were activated after acupuncture, which is similar to our findings, suggesting similar brain responses at different acupoints ( Huang et al, 2022 ). However, Dhond et al (2007) analyzed the functional changes of the brain under various pain states, and proposed that certain limbic brain networks may play a specific therapeutic role in the process of acupuncture analgesia.…”

“…In the absence of clinical conditions, healthy individuals are ideal subjects for determining brain activity during acupuncture stimulation ( Huang et al, 2022 ). To date, neuroimaging techniques have been used to identify brain patterns that activate or deactivate during acupuncture at Hegu in healthy individuals.…”

Functional magnetic resonance imaging studies of acupuncture at ST36: a coordinate-based meta-analysis

“…Importantly, we found that a specific-related network of acupuncture on ST36 was found in several brain areas, including IFG.R, STG.L, cerebellum 8R, and cerebellum crus 2L, which is consistent with a recent systematic review similar to this one that showed the opercular part of IFG.R, STG.L, and right median cingulate/paracingulate gyri (MCG.R) regions were positively activated following ST36 acupuncture (Huang et al, 2022). The IFG.R has a role in modulating cognitive control in several domains, such as inhibitory control and the process of allocating attention (Or-Borichev et al, 2023).…”

Effects of electroacupuncture on perioperative anxiety and stress response in patients undergoing surgery for gastric or colorectal cancer: Study protocol for a randomized controlled trial

“…A fMRI study demonstrated that bodily attention activates the salience network and deactivate the default mode network regardless of stimulation type (48). Some evidence revealed that EA stimulation could cause much more activation in brain regions than manual acupuncture stimulation (49). To some extent, the placebo control in this trial may underestimate acupuncture's treatment effect while satisfying blindness and minimizing the nocebo effect.…”