Table 3.
Mechanism of acupuncture on the regulation of brain regions in peripheral nerve injury.
| Study | Acupoint | Intervention and acupuncture type/parameters | Control intervention | Method | Major effects |
|---|---|---|---|---|---|
| Matsumoto-Miyazaki et al. (2016) | GV 26, Ex-HN 3, bilateral LI 4, ST 36 | MA/10 min | No treatment | TMS | MEP amplitude↑, MEP/Mmax ↑, CMCTs↓, the CST activity of patients with chronic DOC after severe TBI↑ |
| Zhao N. et al. (2018) | At the middle 2/5 of the MS6 line in the affected hemisphere | SA/40 min + LF-rTMS 20 min | SA/40 min | DTI | FMA↑, MBI↑, FAvalue↑, MDvalue↓ |
| Yang et al. (2017) | LI-11, LI-10, TB-5, LI-4, ST-36, GB-34, SP-6, EX-UE9 | MA/Deqi, later hold the needle still for 30 min | No stimulation | TMS | Left MEP↓, right MEP↑, IHI↑ |
| Chen et al. (2015) | GB34 | MA/1.5 Hz, 1 min baseline-30 s Stimulation-three blocks | Non-acupoint | fMRI | Motor-cognition connectivity↑, compensation of unaffected motor cortex and homolateral synkinesis↓ |
| Napadow et al. (2007a,b) | LI-4 | MA/1 Hz, 2 min rest-1 min stimulation-7-min block paradigm | Non-insertive cutaneous stimulation | fMRI | Functional connectivity between the hypothalamus and amygdala: amygdala deactivation↓, hypothalamus activation↑, and vice versa |
| Wang et al. (2016) | RN12, RN10, RN6, RN4, KL17, ST24, Qipang | Abdominal acupuncture/20 min | Non-insertive cutaneous stimulation | fMRI | MADRS scores↓, SDS scores↓, rsFC between the left amygdala and sgACC/ pgACC↑ |
| Napadow et al. (2005) | ST-36 | MA/1 Hz; EA/2 Hz, 100 Hz, 2 min rest-1 min stimulation-7-min block paradigm | Tactile control stimulation | fMRI | Acu, EA: anterior insula hemodynamic signal↑, limbic and paralimbic structures hemodynamic signal ↓ only EA: anterior middle cingulate cortex signal↑, pontine raphe area signal↑ |
| Yan et al. (2005) | Liv3 LI4 | MA/1 Hz | Non-acupoints | fMRI | Liv3, LI4: middle temporal gyrus and cerebellum↑, middle frontal gyrus and inferior parietal lobule↓ Liv3: postcentral gyrus, posterior cingulate, parahippocampal gyrus, BA 7, 19 and 41↑, inferior frontal gyrus, anterior cingulate, BA 17 and 18↓ LI4: temporal pole↑, precentral gyrus, superior temporal gyrus, pulvinar and BA 8, 9 and 45↓ |
| Kong et al. (2002) | LI4 | EA, MA/3 Hz, 1 min baseline-1 min stimulation-5-min block paradigm | fMRI | EA: precentral gyrus, postcentral gyrus/inferior parietal lobule, and putamen/insula fMRI signal ↑ Acu: posterior cingulate, superior temporal gyrus, putamen/insula fMRI signal↓ | |
| Hui et al. (2000) | LI4 | MA/120 times per min, 2 min baseline-2 min stimulation-4 min rest-16 min scan time | Tactile stimulation | fMRI | Modulates the activity of the limbic system and subcortical structures |
| Hui et al. (2005) | ST36 | MA/1 Hz, 2 min baseline-2 min stimulation-3 min rest-10 min scan time | Sensory control stimulation | fMRI | An integrated response of the human cerebro-cerebellar and limbic systems to acupuncture stimulation that correlates with the psychophysical response |
| Li et al. (2015) | SJ5 | MA/twirled ± 180°, 60 times per minutes, 30s stimulation-30s rest-6 min scan time | fMRI | The clinical effect of Deqi during acupuncture is based on brain functional changes | |
| Lu et al. (2014) | ST36 | MA | Non-point | PET | Bilateral amygdalae activation↑, left temporal lobe activation↑, blood perfusion↑, glycol metabolism↑ |
| Shi et al. (2016) | BL40 | MA/depth 2 mm, 5 min | MA/depth 10–20 mm, 5 min | fMRI | Acupuncture modulates the limbic-paralimbic-neocortical network to produce its Deqi effects; The similarity of LPNN and DMN suggests that deep needing may mobilize an important intrinsic brain network for its multiple modulation effects |
| Wang et al. (2013) | LV3 | MA/rotated 180°, 1 Hz, 2 min baseline-2 min stimulation-3 min rest-10 min scan time | Tactile stimulation | fMRI | Pressure was contributing to negative activation of a LPNN; modulatory effects of different needling sensations contribute to acupuncture modulations of LPNN network |
| Napadow et al. (2009) | PC6 | MA/0.5 Hz, 30s stimulation-30s rest-5.5 min scan time | Non-invasive cutaneous stimulation | fMRI | Cognitive load↑, dmPFC activity↑ |
| Fang et al. (2009) | LV3, LV2, ST44 | MA/160 times per min, 180°, 1 min stimulation- 1 min rest-6 min scan time | Sham acupoint stimulation | fMRI | Limbic-paralimbic-neocortical system extensive deactivation↓; sensorimotor cortices, thalamus and occasional paralimbic structures activated↑ |
| Dhond et al. (2008) | PC6 | MA/twirled ± 180°, 0.5 Hz, 5.5 min baseline-5.5 min stimulation-31.5 min scan time | Non-insertive cutaneous stimulation | fMRI | DMN connectivity↑, SMN connectivity↑, post-stimulation spatial extent of resting brain networks to include anti-nociceptive, memory, and affective brain regions↑ |
| He et al. (2014) | LI4 | MA/Deqi, 10 min baseline-10 min stimulation-10 min postacupuncture resting state | fMRI | Connectivity in the primary somatosensory region of both early and late recovery groups↑ | |
| Zhang et al. (2016) | LR3, KI3 | MA/90–180°, 60–90 times per min, lifted and thrust 0.3–0.5 cm, 30 min | Non-acupoint | fMRI | Number of brain regions with altered brain activity after acupuncture at acupoint combinations↑ |
| Jung et al. (2015) | PC6, HT7 | MA/1 Hz | Pseudo-stimulation | fMRI | Salience network↑, default mode network↓ |
| Lee et al. (2013) | ST36 | MA/1 min baseline-30s stimulation-30s rest-5 min scan time | Non-acupoint | fMRI | Blood oxygenation level-dependent signal intensity in basal ganglia, limbic system, and cerebellum↓ |
| Napadow et al. (2009) | PC6 | MA/0.5 Hz, 30s baseline-30s stimulation-30s rest-5.5 min scan time | Non-insertive cutaneous stimulation | fMRI | Anterior dmPFC activity↑, posterior dmPFC activity↑ |
| Long et al. (2016) | ST36 | MA/6 min stimulation-6 min rest-4 min break | Non-acupoint | fMRI | Centrality in parahippocampal gyrus↑, centrality in middle temporal gyrus↑, DMN↑ |
| Lin et al. (2016) | LI4 | SNA + MS/twirled rotated, 180°, 1 Hz, 20s for15min | SNA, TNA/15 min; TENS/1 Hz, 20s for 15 min | fMRI | Enhance the acupuncture dose induce different DMN modulatory effects; TNA induces the most extensive DMN modulation |
| Dhond et al. (2008) | PC6 | MA/twirled (∼ ± 180°), 0.5 Hz, 5.5 min rest-5.5 min stimulation-31.5 min scan time | Non-insertive cutaneous stimulation | fMRI | DMN connectivity with pain, affective and memory related brain regions↑, SMN connectivity with pain-related brain regions ↑ |
| Ren et al. (2008) | Neiguan, Waiguan, Sanyinjiao, Zusanli | EA/1 mA, 10 Hz, 30 min | Dendritic spine density↑, ephrin-A5↑, neural plasticity at the peri-infarct cerebral cortex in acute cerebral ischemia rat↑ | ||
| Liang et al. (2017) | ST36, LI11 | EA/2 mA, 1/20 Hz, 30 min | The modified neurologic severity scores↑, neural activity of motor function-related brain regions↑ | ||
| Wu et al. (2018a,b) | GB30, ST36 | EA/0.2 mA, 1/20 Hz, 15 min | Limbic/paralimbic areas fluctuated↑ | ||
| Maeda et al. (2017) | TW5 PC7 + three additional acupoints | EA/2 Hz, 20 min | Sham acupuncture | fMRI | Primary somatosensory cortex somatotopy↑ |
MA, manual acupuncture; TMS, transcranial magnetic stimulation; MEP, motor-evoked potential; CMCT, Central motor conduction time; CST, cortico spinal tract; DOC, disorders of consciousness; TBI, traumatic brain injury; DTI, Diffusion tensor imaging; FA, fractional anisotropy; MD, mean diffusion; LF-rTMS, low frequency repetitive transcranial magnetic stimulation; IHI, interhemispheric inhibition; SA, scalp acupuncture; Deqi, a characteristic sensation of aching and tingling; 7-min block paradigm including a 2-min rest, 1-min stimulation, 2-min rest, 1-min stimulation, 1-min rest block; MADRS, Montgomery–Åsberg Depression Rating Scale scores; SDS, Self-Rating Depression Scale scores; sgACC, subgenual anterior cingulate cortex; pgACC, preguenual anterior cingulate cortex; rsFC, resting state functional connectivity; DMN, default mode networks; LPNN, limbic-paralimbic-neocortical network; dmPFC, dorsomedial prefrontal cortex; SMN, sensorimotor network; SNA, single needle acupuncture; TENS, transcutaneous electrical nerve stimulation; TNA, three needle acupuncture; MS, manual stimulation.