Time-variant fMRI activity in the brainstem and higher structures in response to acupuncture

Enhancing emotion regulation: investigating the efficacy of transcutaneous electrical acupoint stimulation at PC6 in reducing fear of heights

This study investigated the impact of transcutaneous electrical acupoint stimulation (TEAS) at Neiguan acupoint (PC6) on the physiological and behavioral responses of participants exposed in virtual height. 40 participants were included in the study and were randomly assigned to either a control group or an intervention group. Participants had an immersive experience with a VR interactive platform that provided somatosensory interaction in height stimulation scenes. Psychological scores, behavioral and cognitive performance, and physiological responses were recorded and analyzed. The results indicated that the intervention group had significantly lower fear scores compared to the control group. Analysis of heart rate variability revealed that the intervention group exhibited improved heart rate variability, indicating enhanced cardiovascular function and emotion regulation. The behavioral and cognitive results demonstrated that the intervention group exhibited higher left eye openness, faster reaction times, and greater movement distance, suggesting enhanced attentional focus, cognitive processing, and reduced avoidance behaviors. These findings suggest that TEAS at PC6 can effectively reduce fear and improve the regulation of physiological and behavioral responses to negative emotional stimuli.

Effect of Emotional Freedom Technique Applied to Patients Before Laparoscopic Cholecystectomy on Surgical Fear and Anxiety: A Randomized Controlled Trial

PURPOSE

No studies have investigated the effect of the Emotional Freedom Technique (EFT) on the surgical fears and anxieties of patients before laparoscopic cholecystectomy. This study aimed to determine the effect of EFT on patients' surgical fears and anxieties before laparoscopic cholecystectomy.

DESIGN

The research was conducted using a pretest, post-test, and randomized controlled experimental research design.

METHODS

A total of 112 patients (56 in the intervention group and 56 in the control group) were included in the study. While routine care and treatment practices were applied to the control group, EFT was applied to the intervention group. A Patient Information Form, an Anxiety Specific to Surgery Questionnaire, a Surgical Fear Questionnaire, and Subjective Units of Disturbance (SUD) were used to collect the research data.

FINDINGS

There was no significant difference between the groups in terms of descriptive and clinical features (P > .05). The post-test score averages of EFT group in the Surgical Fear Questionnaire, Anxiety Specific to Surgery Questionnaire, and SUD were significantly lower than in the control group (P < .001). The EFT significantly reduced the SUD scores of the patients by 54.4% (η2 = 0.544, P < .001).

CONCLUSIONS

EFT was found to be useful in clinical practice in the preoperative period, reducing surgery-specific anxiety and surgical fear. EFT can be recommended for application during the preoperative period in clinics.

Immediate neural effects of acupuncture manipulation time for stroke with motor dysfunction: a fMRI pilot study

Introduction

Acupuncture is widely utilized as a beneficial intervention for the treatment of motor dysfunction after stroke, and its effectiveness depends on the stimulation dose. Manipulation time is an important factor affecting the dose. This trial aimed use fMRI to explore the immediate neural effects in stroke patients with motor dysfunction by different acupuncture manipulation times, to reveal the neural mechanism of acupuncture manipulation.

Methods

Thirty participants were divided into three groups according to different acupuncture times. Each group received the same acupoint prescription, although the continuous manipulation time of each acupoint in three groups was 1-min, 2-min, and 3-min, respectively. The NIHSS, FMA and fMRI-BOLD in each participant we obtained before and after acupuncture manipulation. Then, we used the regional homogeneity (ReHo) algorithm to analyze the changes of brain function and to compare the neural effects at different acupuncture manipulation times.

Results

There were no significant differences in NIHSS and FMA scores between and within groups. Longitudinal analysis of ReHo values indicated that the right inferior frontal gyrus was activated in the 1-min group, the right insula in the 2-min group, and the right inferior temporal gyrus in the 3-min group. Compared with the 1-min group, the 2-min group showed the ReHo values of the right precentral gyrus was decreased, and the 3-min group showed the left cerebellum posterior lobe was increased, the right posterior cingulate gyrus and the right anterior cingulate gyrus were decreased. Compared with the 2-min group, the 3-min group showed the ReHo values of the right cerebellum anterior lobe was increased.

Conclusion

Our findings suggest that acupuncture at different manipulation times caused different changes of the neural effects in stroke patients, and the volume of activated voxel clusters is positively correlated with the manipulation time. Longer acupuncture manipulation could drive SMN and DMN in stroke patients, which may be the potential neurological mechanism of acupuncture manipulation affecting the recovery of motor dysfunction.

Transcutaneous electrical acupoint stimulation versus dexamethasone for prophylaxis of postoperative nausea and vomiting in breast surgery: A non-inferiority randomized controlled trial

BACKGROUND

Transcutaneous electrical acupoint stimulation and dexamethasone can reduce postoperative nausea and/or vomiting. In this noninferiority study, we compared the effects of Neiguan acupoint (PC6) transcutaneous electrical acupoint stimulation with dexamethasone to prevent postoperative nausea and/or vomiting in female patients undergoing breast surgery.

METHODS

In total, 280 patients were randomized into the following 2 groups: transcutaneous electrical acupoint stimulation (n = 140) and dexamethasone (n = 140). Transcutaneous electrical acupoint stimulation was performed 0.5 hours before anesthesia induction, immediately after entering the post-anesthesia care unit, and every 3 hours after leaving the post-anesthesia care unit. In the postoperative ward, the anesthetist instructed the patient's family members to assist the patient with PC6 patient-controlled transcutaneous electrical acupoint stimulation. Patients in the dexamethasone group were given 8 mg dexamethasone (intravenously) at 0.5 hours before induction of anesthesia. The incidence of nausea, vomiting, need for rescue antiemetics, patient satisfaction score, and the feasibility results of PC6 patient-controlled transcutaneous electrical acupoint stimulation were recorded 24 hours after surgery.

RESULT

Within 0 to 24 hours after surgery, the incidence of postoperative nausea and/or vomiting in the transcutaneous electrical acupoint stimulation group was not inferior to the dexamethasone group (31.1% vs 27.9%, per protocol risk difference 3.2; 95% confidence interval -7.7 to 14.0). The results of the intention-to-treat analysis (30.7% vs 27.1%, risk difference 3.6; 95% confidence interval -7.0 to 14.2) agreed with the per protocol analysis. Patient satisfaction score in the transcutaneous electrical acupoint stimulation group was higher than that in the dexamethasone group (3.9 ± 0.1 vs 3.6 ± 0.1, P = .003). The scheme of preventing postoperative nausea and/or vomiting by PC6 patient-controlled transcutaneous electrical acupoint stimulation was feasible.

CONCLUSION

Transcutaneous electrical acupoint stimulation was noninferior to dexamethasone in preventing postoperative nausea and/or vomiting within 24 hours after breast surgery. Neiguan acupoint patient-controlled transcutaneous electrical acupoint stimulation was feasible to prevent postoperative nausea and/or vomiting.

Modulation effects of different treatments on periaqueductal gray resting state functional connectivity in knee osteoarthritis knee pain patients

BACKGROUND

The analgesic effect of acupuncture is widely recognized, but the mechanical characteristics of acupuncture for pain relief, compared to non-steroidal anti-inflammatory (NSAIDs) and placebo medication, remain unknown.

AIMS

To compare the modulation effects of acupuncture treatment with NSAIDs and placebo medication on descending pain modulation system (DPMS) in knee osteoarthritis (KOA) patients.

METHODS

This study recruited 180 KOA patients with knee pain and 41 healthy controls (HCs). Individuals with KOA knee pain were divided randomly into groups of verum acupuncture (VA), sham acupuncture (SA), celecoxib (SC), placebo (PB), and waiting list (WT), with 36 patients in each group. VA and SA groups included ten sessions of puncturing acupoints or puncturing non-acupoints acupuncture treatment for two successive weeks. Celecoxib capsules were continuously given orally to patients in the SC group at a dosage of 200 mg daily for 2 weeks. In the PB group, patients received a placebo capsule once a day for 2 weeks at the same dosage as celecoxib capsules. In the WL group, patients did not receive any treatment. Patients underwent a resting-state BOLD-fMRI scan pre- and post-receiving the therapy, whereas HCs only underwent a baseline scan. Seed (ventrolateral periaqueductal gray, vlPAG, a key node in DPMS) based resting-state functional connectivity (rs-FC) was applied in the data analysis.

RESULTS

All groups demonstrated improved knee pain scores relative to the initial state. There was no statistical difference between the VA and SA groups in all clinical outcomes, and vlPAG rs-FC alterations. KOA knee pain individuals reported higher vlPAG rs-FC in the bilateral thalamus than HCs. KOA knee pain patients in the acupuncture group (verum + sham, AG) exhibited increased vlPAG rs-FC with the right dorsolateral prefrontal cortex (DLPFC) and the right angular, which is associated with knee pain improvement. In contrast with the SC and PB group, the AG exhibited significantly increased vlPAG rs-FC with the right DLPFC and angular. Contrary to the WT group, the AG showed greater vlPAG rs-FC with the right DLPFC and precuneus.

CONCLUSIONS

Acupuncture treatment, celecoxib, and placebo medication have different modulation effects on vlPAG DPMS in KOA knee pain patients. Acupuncture could modulate vlPAG rs-FC with brain regions associated with cognitive control, attention, and reappraisal for knee pain relief in KOA patients, compared with celecoxib and placebo medication.

Transcutaneous electrical acupoint stimulation induced sedative effects in healthy volunteers: A resting-state fMRI study

Background

Previous studies indicated the sedative effect of acupoint stimulation. However, its mechanism remains unclear. This study aimed to investigate the sedative effect of transcutaneous electrical acupoint stimulation (TEAS) and to explore the brain regions involved in this effect in healthy volunteers using functional magnetic resonance imaging (fMRI) techniques.

Methods

In this randomized trial, 26 healthy volunteers were randomly assigned to the TEAS group (receiving 30 min of acupoint stimulation at HT7/PC4) and the control group. fMRI was conducted before and after the intervention. The primary outcome was the BIS value during the intervention. Secondary outcomes included the amplitude of low-frequency fluctuation (ALFF) and region of interest (ROI)-based functional connectivity (FC) showed by fMRI.

Results

In healthy volunteers, compared with the control group, ALFF values in the TEAS-treated volunteers decreased in the left thalamus, right putamen, and midbrain, while they increased in the left orbitofrontal cortex. More FC existed between the thalamus and the insula, middle cingulate cortex, somatosensory cortex, amygdala, and putamen in subjects after TEAS treatment compared with subjects that received non-stimulation. In addition, ALFF values of the thalamus positively correlated with BIS in both groups.

Conclusion

Transcutaneous electrical acupoint stimulation could induce a sedative effect in healthy volunteers, and inhibition of the thalamus was among its possible mechanisms.

Clinical trial registration

www.ClinicalTrials.gov; identifier: NCT01896063.

A Biophysical Model for Cardiovascular Effects of Acupuncture-Underlying Mechanisms Based on First Principles

According to recent translations by medical professionals of the foundational texts of Chinese Medicine, the acupuncture channel system can be reconciled with the neurovasculature. From there, the underlying mechanisms of the effects of acupuncture can be drawn from established physiology and known physical laws. A large body of research has been carried out using cardiovascular markers to measure the effects of acupuncture. Three of these parameters are re-viewed and explored anew in detail. The focus is on changes in microcirculation, blood pressure, and heart rate variability. The physiological mechanisms accounting for the observed changes are proposed to be ascending vasodilatation, resetting of the baroreceptor reflex, and re-organization of heart beating patterns around intrinsically assigned attractor sets.

Effect of Sham Acupuncture on Chronic Pain: A Bayesian Network Meta-analysis

BACKGROUND

Along with increasing research on acupuncture for chronic pain, the validity of sham acupuncture (SA) has also been argued.

METHODS

Nine databases were searched for randomized controlled trials (RCTs) from the inception date to July 5, 2022. Using Markov Chain Monte Carlo methods, a Bayesian multiple treatment network meta-analysis (NMA) with random-effects model was conducted.

RESULTS

A total of 62 RCTs with 6806 patients and four kinds of treatments (real acupuncture (RA), non-acupuncture (NA), penetrative SA (PSA) and non-penetrative SA (NPSA)) were included. The results indicated that both NPSA and PSA were not superior to NA in improving chronic pain (NPSA: MD -4.77 [95% CI, -11.09 to 1.52]; PSA: MD, -4.96 [95% CI, -10.38 to 0.48]). After combining NPSA and PSA into the SA group, the weak trend of pain relief from SA was still not statistically significant (MD, -4.91 [95% CI, -9.93 to 0.05]). NPSA and PSA had similar effects (MD, 0.18 [95% CI, -5.45 to 5.81]). RA was significantly associated with pain relief, compared with NPSA and PSA (NPSA: MD, -12.03 [95% CI, -16.62 to -7.41]; PSA: MD, -11.85 [95% CI, -15.48 to -8.23]). The results were generally consistent regardless of pain phenotype, frequency, duration, acupuncture methods, analgesic intake, or detection bias.

CONCLUSION

These results suggested that acupuncture was significantly associated with reduced chronic pain. The two kinds of placebo acupuncture, NPSA and PSA, have similar effects. Both NPSA and PSA, with a weak but not significant effect, are appropriate to be inert placebo controls in RCTs for chronic pain.

Acupuncture Treatment Decreased Temporal Variability of Dynamic Functional Connectivity in Chronic Tinnitus

Acupuncture is recommended for the relief of chronic tinnitus in traditional Chinese medicine, but the underlying neural mechanism remains unclear. The human brain is a dynamic system, and it’s unclear about acupuncture’s effects on the dynamic functional connectivity (DFC) of chronic tinnitus. Therefore, this study based on resting-state functional magnetic resonance imaging (fMRI) investigates abnormal DFC in chronic tinnitus patients and the neural activity change evoked by acupuncture treatment for tinnitus. In this study, 17 chronic tinnitus patients and 22 age- and sex-matched normal subjects were recruited, and their tinnitus-related scales and hearing levels were collected. The fMRI data were measured before and after acupuncture, and then sliding-window and k-means clustering methods were used to calculate DFC and perform clustering analysis, respectively. We found that, compared with the normal subjects, chronic tinnitus patients had higher temporal variability of DFC between the supplementary motor area and medial part of the superior frontal gyrus, and it positively correlated with hearing loss. Clustering analysis showed higher transition probability (TP) between connection states in chronic tinnitus patients, and it was positively correlated with tinnitus severity. Furthermore, the findings showed that acupuncture treatment might improve tinnitus. DFC between the posterior cingulate gyrus and angular gyrus in chronic tinnitus patients after acupuncture showed significantly decreased, and it positively correlated with the improvement of tinnitus. Clustering analysis showed that acupuncture treatment might promote chronic tinnitus patients under lower DFC state, and it also positively correlated with the improvement of tinnitus. This study suggests that acupuncture as an alternative therapy method might decrease the tinnitus severity by decreasing the time variability of DFC in chronic tinnitus patients.

Acupuncture Modulation Effect on Pain Processing Patterns in Patients With Migraine Without Aura

Introduction

In this retrospective study, resting-state functional connectivity (FC) in patients with migraine was analyzed to identify potential pathological pain processing patterns and compared them to those in healthy controls (HCs). The FC patterns in patients between pre- and post-acupuncture sessions were also analyzed to determine how acupuncture affects neurological activity and pain perception during the migraine interictal period.

Methods

In total, 52 patients with migraine without aura (MwoA) and 60 HCs were recruited. Patients with migraine were given acupuncture treatment sessions for 4 weeks. As a primary observation, functional magnetic resonance images were obtained at the beginning and end of the sessions. HCs received no treatment and underwent one functional magnetic resonance imaging (fMRI) scan after enrollment. After the fMRI data were preprocessed, a region of interest (ROI)-to-ROI analysis was performed with predefined ROIs related to pain processing regions.

Results

The first analysis showed significantly different FCs between patients with MwoA and HCs [false discovery rate corrected p-value (p-FDR) < 0.05]. The FCs were found to be mainly between the cingulate gyrus (CG) and the insular gyrus, the CG and the inferior parietal lobule (IPL), the CG and the superior frontal gyrus, and the middle frontal gyrus and the IPL. The second analysis indicated that acupuncture treatment partly restored the different FCs found in the first analysis (p-FDR < 0.05). Furthermore, subgroup analysis found different brain activity patterns in headache-intensity restored condition and headache-frequency restored condition. Lastly, the correlation analysis suggested a potential correlation between FCs and clinical symptoms (p < 0.05).

Conclusion

This study suggests that pain processing is abnormal in migraine, with significantly abnormal FCs in the frontal, parietal, and limbic regions. This finding could be a typical pathological feature of migraine. Acupuncture has been identified to relieve headache symptoms in two ways: it restores the pain processing function and regulates pain perception.

Mapping dependencies of BOLD signal change to end-tidal CO2: linear and nonlinear modeling, and effect of physiological noise correction

BACKGROUND

Disentangling physiological noise and signal of interest is a major issue when evaluating BOLD-signal changes in response to breath holding. Currently-adopted approaches for retrospective noise correction are general-purpose, and have non-negligible effects in studies on hypercapnic challenges.

NEW METHOD

We provide a novel approach to the analysis of specific and non-specific BOLD-signal changes related to end-tidal CO₂ (P_ETCO₂) in breath-hold fMRI studies. Multiple-order nonlinear predictors for P_ETCO₂ model a region-dependent nonlinear input-output relationship hypothesized in literature and possibly playing a crucial role in disentangling noise. We explore Retrospective Image-based Correction (RETROICOR) effects on the estimated BOLD response, applying our analysis both with and without RETROICOR and analyzing the linear and non-linear correlation between P_ETCO₂ and RETROICOR regressors.

RESULTS

The RETROICOR model of noise related to respiratory activity correlated with P_ETCO₂ both linearly and non-linearly. The correction affected the shape of the estimated BOLD response to hypercapnia but allowed to discard spurious activity in ventricles and white matter. Activation clusters were best detected using non-linear components in the BOLD response model.

COMPARISON WITH EXISTING METHOD

We evaluated the side-effects of standard physiological noise correction procedure, tailoring our analysis on challenging understudied brainstem and subcortical regions. Our novel approach allowed to characterize delays and non-linearities in BOLD response.

CONCLUSIONS

RETROICOR successfully avoided false positives, still broadly affecting the estimated non-linear BOLD responses. Non-linearities in the model better explained CO₂-related BOLD signal fluctuations. The necessity to modify the standard procedure for physiological-noise correction in breath-hold studies was addressed, stating its crucial importance.

Comparison of continuous sampling with active noise cancelation and sparse sampling for cortical and subcortical auditory functional MRI

PURPOSE

Detecting sound-related activity using functional MRI requires the auditory stimulus to be more salient than the intense background scanner acoustic noise. Various strategies can reduce the impact of scanner acoustic noise, including "sparse" temporal sampling with single/clustered acquisitions providing intervals without any background scanner acoustic noise, or active noise cancelation (ANC) during "continuous" temporal sampling, which generates an acoustic signal that adds destructively to the scanner acoustic noise, substantially reducing the acoustic energy at the participant's eardrum. Furthermore, multiband functional MRI allows multiple slices to be collected simultaneously, thereby reducing scanner acoustic noise in a given sampling period.

METHODS

Isotropic multiband functional MRI (1.5 mm) with sparse sampling (effective TR = 9000 ms, acquisition duration = 1962 ms) and continuous sampling (TR = 2000 ms) with ANC were compared in 15 normally hearing participants. A sustained broadband noise stimulus was presented to drive activation of both sustained and transient auditory responses within subcortical and cortical auditory regions.

RESULTS

Robust broadband noise-related activity was detected throughout the auditory pathways. Continuous sampling with ANC was found to give a statistically significant advantage over sparse sampling for the detection of the transient (onset) stimulus responses, particularly in the auditory cortex (P < .001) and inferior colliculus (P < .001), whereas gains provided by sparse over continuous ANC for detecting offset and sustained responses were marginal (p ~ 0.05 in superior olivary complex, inferior colliculus, medial geniculate body, and auditory cortex).

CONCLUSIONS

Sparse and continuous ANC multiband functional MRI protocols provide differing advantages for observing the transient (onset and offset) and sustained stimulus responses.

Global Trends and Performances of Magnetic Resonance Imaging Studies on Acupuncture: A Bibliometric Analysis

Objectives: To summarize development processes and research hotspots of MRI research on acupuncture and to provide new insights for researchers in future studies.

Methods: Publications regarding MRI on acupuncture from inception to 2020 were downloaded from the Web of Science Core Collection. VOSviewer 1.6.15 and CiteSpace V software were used for bibliometric analyses. The main analyses include collaboration analyses between countries/institutions/authors, co-occurrence analysis between keywords, as well as analyses on keyword bursts, citation references, and clusters of references.

Results: A total of 829 papers were obtained with a continually increased trend over time. The most productive country and institution in this field were the People's Republic of China (475) and KyungHee University (70), respectively. Evidence-based Complementary and Alternative Medicine (83) was the most productive journal, and Neuroimage (454) was the most co-cited journal. Dhond's et al. (2008) article (co-citation counts: 58) and Napadow's et al. (2005) article (centrality: 0.21) were the most representative and symbolic references, with the highest co-citation number and centrality, respectively. Jie Tian had the highest number of publications (35) and Kathleen K S Hui was the most influential author (280 co-citations). The four hot topics in MRI on acupuncture were acupuncture, fMRI, pain, and stimulation. The three frontier topics were connectivity, modulation, and fMRI. Based on the clustering of co-cited documents, chronic low back pain, sham electro-acupuncture treatment, and clinical research were the main research directions.

Conclusion: This study provides an in-depth perspective for MRI research on acupuncture and provides researchers with valuable information to determine the current status, hot spots, and frontier trends of MRI research on acupuncture.

Dynamic brain-to-brain concordance and behavioral mirroring as a mechanism of the patient-clinician interaction

The patient-clinician interaction can powerfully shape treatment outcomes such as pain but is often considered an intangible "art of medicine" and has largely eluded scientific inquiry. Although brain correlates of social processes such as empathy and theory of mind have been studied using single-subject designs, specific behavioral and neural mechanisms underpinning the patient-clinician interaction are unknown. Using a two-person interactive design, we simultaneously recorded functional magnetic resonance imaging (hyperscanning) in patient-clinician dyads, who interacted via live video, while clinicians treated evoked pain in patients with chronic pain. Our results show that patient analgesia is mediated by patient-clinician nonverbal behavioral mirroring and brain-to-brain concordance in circuitry implicated in theory of mind and social mirroring. Dyad-based analyses showed extensive dynamic coupling of these brain nodes with the partners' brain activity, yet only in dyads with pre-established clinical rapport. These findings introduce a putatively key brain-behavioral mechanism for therapeutic alliance and psychosocial analgesia.

3D Exploration of the Brainstem in 50-Micron Resolution MRI

The brainstem, a structure of vital importance in mammals, is currently becoming a principal focus in cognitive, affective, and clinical neuroscience. Midbrain, pontine and medullary structures serve as the conduit for signals between the forebrain and spinal cord, are the epicenter of cranial nerve-circuits and systems, and subserve such integrative functions as consciousness, emotional processing, pain, and motivation. In this study, we parcellated the nuclear masses and the principal fiber pathways that were visible in a high-resolution T2-weighted MRI dataset of 50-micron isotropic voxels of a postmortem human brainstem. Based on this analysis, we generated a detailed map of the human brainstem. To assess the validity of our maps, we compared our observations with histological maps of traditional human brainstem atlases. Given the unique capability of MRI-based morphometric analysis in generating and preserving the morphology of 3D objects from individual 2D sections, we reconstructed the motor, sensory and integrative neural systems of the brainstem and rendered them in 3D representations. We anticipate the utilization of these maps by the neuroimaging community for applications in basic neuroscience as well as in neurology, psychiatry, and neurosurgery, due to their versatile computational nature in 2D and 3D representations in a publicly available capacity.

Does the Acupoint Specificity Exist? Evidence from Functional Neuroimaging Studies

BACKGROUND

Using functional neuroimaging techniques to explore the central mechanism of acupoint specificity, the key of acupuncture theory and clinical practice, has attracted increasing attention worldwide. This review aimed to investigate the current status of functional neuroimaging studies on acupoint specificity and explore the potential influencing factors for the expression of acupoint specificity in neuroimaging studies.

METHODS

PubMed database was searched from January 1st, 1995 to December 31st, 2016 with the language restriction in English. Data including basic information, methodology and study results were extracted and analyzed from the eligible records.

RESULTS

Seventy-nine studies were finally enrolled. 65.8% of studies were performed in China, 73.4% of studies were conducted with healthy subjects, 77.2% of studies chose manual acupuncture as the intervention, 86.1% of studies focused on the instant efficacy and 89.9% of studies used functional magnetic resonance imaging as scanning technique. The average sample size was 16 per group. The comparison of verum acupoints and sham acupoints were the main body of acupoint specificity researches. 93.7% of studies obtained the positive results and favored the existence of acupoint specificity.

CONCLUSION

This review affirmed the existence of acupoint specificity and deemed that the acupoint specificity was relative. Multiple factors such as participants, sample size, acupoint combinations, treatment courses, and types of acupoint could influence the expression of acupoint specificity.

Multiple Brain Networks Mediating Stimulus-Pain Relationships in Humans

The brain transforms nociceptive input into a complex pain experience comprised of sensory, affective, motivational, and cognitive components. However, it is still unclear how pain arises from nociceptive input and which brain networks coordinate to generate pain experiences. We introduce a new high-dimensional mediation analysis technique to estimate distributed, network-level patterns that formally mediate the relationship between stimulus intensity and pain. We applied the model to a large-scale analysis of functional magnetic resonance imaging data (N = 284), focusing on brain mediators of the relationship between noxious stimulus intensity and trial-to-trial variation in pain reports. We identify mediators in both traditional nociceptive pathways and in prefrontal, midbrain, striatal, and default-mode regions unrelated to nociception in standard analyses. The whole-brain mediators are specific for pain versus aversive sounds and are organized into five functional networks. Brain mediators predicted pain ratings better than previous brain measures, including the neurologic pain signature (Wager et al. 2013). Our results provide a broader view of the networks underlying pain experience, as well as novel brain targets for interventions.

Modulation Effect of Acupuncture on Functional Brain Networks and Classification of Its Manipulation With EEG Signals

Acupuncture manipulation is the key of Chinese medicine acupuncture therapy. In clinical practice, different acupuncture manipulations are required to achieve different therapeutic effects, which means it is crucial to distinguish different acupuncture manipulations. In this paper, we proposed a classification framework for different acupuncture manipulations, which employed the graph theory and machine learning method. Multichannel EEG signals evoked by acupuncture at "Zusanli" acupoint were recorded from healthy humans by two acupuncture manipulations: twirling-rotating (TR) and lifting-thrusting (LT). Phase locking value was used to estimate the phase synchronization of pair-wise EEG channels. It was found that acupunctured by TR manipulation exhibit significantly higher synchronization degree than acupunctured by LT manipulation. With the construction of functional brain network, the topological features of graph theory were extracted. Taken the network features as inputs, machine learning classifiers were established to classify acupuncture manipulations. The highest accuracy can achieve 92.14% with support vector machine. By further optimizing the network features utilized in machine learning classifiers, it was found that the combination of node betweenness and small world network index is the most effective factor for acupuncture manipulations classification. These findings suggested that our approach provides new ideas for automatically identify acupuncture manipulations from the perspective of functional brain networks and machine learning methods.

Brainstem neuroimaging of nociception and pain circuitries

The brainstem is known to be an important brain area for nociception and pain processing, and both relaying and coordinating signaling between the cerebrum, cerebellum, and spinal cord. Although preclinical models of pain have characterized the many roles that brainstem nuclei play in nociceptive processing, the degree to which these circuitries extend to humans is not as well known. Unfortunately, the brainstem is also a very challenging region to evaluate in humans with neuroimaging. The challenges for human brainstem imaging arise from the location of this elongated brain structure, proximity to cardiorespiratory noise sources, and the size of its constituent nuclei. These challenges can require dedicated approaches to brainstem imaging, which should be adopted when study hypotheses are focused on brainstem processing of nociception or modulation of pain perception. In fact, our review will highlight many pain neuroimaging studies that have reported some brainstem involvement in nociceptive processing and chronic pain pathology. However, we note that with recent advances in neuroimaging leading to improved spatial and temporal resolution, more studies are needed that take advantage of data collection and analysis methods focused on the challenges of brainstem neuroimaging.

Exploring the supra linear relationship between PetCO2 and fMRI signal change with ICA

The relationships between brain functions and the respiratory system are complex. Disentangling brain activity related to CO₂ changes from nonspecific vasoreactivity is a challenge when studying brain activity involved in the control of breathing with fMRI. In this work, we analyzed a dose dependent relationship between arterial CO₂ levels and brain response. To accomplish this goal, we developed a gas administration protocol, together with multi-subject ICA and specific nonlinear post-processing analysis. Our results highlighted a supra-linear response to CO₂ challenges in brainstem, thalamus and putamen. Results were discussed in the light of current knowledge about the central respiratory network.

A Randomized, Double-Blind, Sham-Controlled Study Assessing Electroacupuncture for the Management of Postoperative Pain after Percutaneous Nephrolithotomy

INTRODUCTION

Percutaneous nephrolithotomy (PCNL) is the gold standard procedure for large renal calculi but postoperative (PO) pain remains a concern. Modifications of the PCNL technique and intraoperative and PO strategies have been tested to reduce pain. PO pain control reducing risk of long-term pain medication and narcotic use is of considerable importance. Acupuncture is a common medical procedure shown to alleviate PO pain. Some benefits are that it is nonpharmacologic, easy to administer, and safe. The purpose of this study was to evaluate the effects of electroacupuncture (EA) on PO pain in patients undergoing PCNL.

MATERIALS AND METHODS

This was a randomized, double-blind, sham-controlled study. The study was Institutional Review Board approved and performed under standard ethical guidelines. Fifty-one patients undergoing PCNL by a single surgeon were randomized to one of the three groups: true EA (n = 17), sham EA (SEA, n = 17), and no acupuncture (control, n = 17). The EA and SEA were performed by a single licensed acupuncturist <1 hour before operation. PCNL was performed without the use of intraoperative nerve block(s) or local anesthetic. Pain scores (visual analog scale [VAS]), narcotic use (morphine equivalents), and side effects were recorded at set intervals postoperatively.

RESULTS

Mean VAS scores for flank and abdomen pain were lower at all time periods in the EA compared with the SEA and control groups. Mean cumulative opioid usage was lower in the EA group immediately postoperatively compared with both SEA and control groups. Two patients in the EA group did not require any PO narcotics. No differences between groups were found for PO nausea and vomiting. No adverse effects of EA or SEA were noted.

CONCLUSIONS

EA significantly reduced PO pain and narcotic usage without any adverse effects after PCNL. This promising treatment for managing PO pain warrants further investigation.

Interactions between gut permeability and brain structure and function in health and irritable bowel syndrome

Changes in brain-gut interactions have been implicated in the pathophysiology of chronic visceral pain in irritable bowel syndrome (IBS). Different mechanisms of sensitization of visceral afferent pathways may contribute to the chronic visceral pain reports and associated brain changes that characterize IBS. They include increased gut permeability and gut associated immune system activation, and an imbalance in descending pain inhibitory and facilitatory mechanisms. In order to study the involvement of these mechanisms, correlations between gut epithelial permeability and live bacterial passage, and structural and functional brain connectivity were measured in women with moderate-to-severe IBS and healthy women. The relationships between gut permeability and functional and anatomical connectivity were significantly altered in IBS compared with the healthy women. IBS participants with lower epithelial permeability reported increased IBS symptoms, which was associated with increased functional and structural connectivity in endogenous pain facilitation regions. The findings suggest that relationships between gut permeability and the brain are significantly altered in IBS and suggest the existence of IBS subtypes based on these interactions.

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Brain-gut interactions are significantly altered in irritable bowel syndrome.

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Brain-gut interactions engage pain modulation brain regions in healthy women.

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Normal levels of gut permeability in IBS are linked with endogenous pain facilitation.

Psychotherapy With Somatosensory Stimulation for Endometriosis-Associated Pain: The Role of the Anterior Hippocampus

BACKGROUND

Endometriosis is a gynecological disorder affecting 6%-10% of all women in their reproductive age. There is an emerging view in the literature that psychological trauma plays a central role in the pathogenesis of pelvic pain, one of the core symptoms of endometriosis. Here we report central nervous system mechanisms of a novel combination of psychotherapy and somatosensory stimulation that has recently shown remarkable effects in reducing pain, anxiety, and depressive symptoms in these patients.

METHODS

We conducted a randomized controlled trial; 67 patients with severe endometriosis-associated pain (maximum pain: 7.6 ± 2.0, average pain: 4.5 ± 2.0 on a 10-point numeric rating scale) were included in the study and randomly allocated to intervention (35 patients) or waitlist control (32 patients) groups. Resting-state functional magnetic resonance imaging was used to assess brain connectivity of these patients at baseline, after 3 months of therapy, and after 6 months. The analysis focused on the hippocampus.

RESULTS

We identified a cortical network comprising the right anterolateral hippocampus-a region modulating the hypothalamic-pituitary-adrenal axis-and somatosensory, viscerosensory, and interoceptive brain regions. Regression analysis showed that reduction in connectivity predicted therapy-induced improvement in patients׳ anxiety.

CONCLUSIONS

We have identified a putative neurobiological mechanism underlying the potent combination of psychotherapy and somatic stimulation in treating symptoms of endometriosis.

Brain activation during the expectations of sensory experience for cutaneous electrical stimulation

The brain actively interprets sensory inputs by integrating top-down and bottom-up information. Humans can make inferences on somatosensation based on prior experiences and expectations even without the actual stimulation. We used functional magnetic resonance imaging to investigate the neural substrates of the expectations of the sensory experience of cutaneous electrical stimulation on acupoint without actual stimuli. This study included 22 participants who wore sticker-type electrodes attached on three different acupoints on different body regions: CV17 (chest), CV23 (chin), and left PC6 (arm). Participants evaluated de qi sensations after they expected electrical stimulation on those points in random order without actual stimulation. All stimuli were presented with corresponding visual information of the stimulation sites. The control condition included the same visual information but outside the body. The expectations of cutaneous electrical stimuli without actual stimulation on three acupoints resulted in greater de qi sensation compared to the control condition. Cognitive components of cutaneous electrical stimulation exhibited greater brain activation in the anterior insula, pre-supplementary motor area, and secondary somatosensory area. The expectations of acupuncture stimulation exhibited a distinct experience of somatosensation as well as brain activations in insula and pre-supplementary motor area. Our findings suggest that the sensory experience of the pseudo-cutaneous stimulation may be derived from the predictive role of the salience network in monitoring internal and external body states.

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The pseudo-cutaneous stimulation can elicit remarkable somatic sensations.

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Insula and pre-SMA are involved in the expectations of sensory experience.

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Somatic sensation from pseudo-stimulation is influenced by top-down information.

Modulation of brainstem activity and connectivity by respiratory-gated auricular vagal afferent nerve stimulation in migraine patients

Migraine pathophysiology includes altered brainstem excitability, and recent neuromodulatory approaches aimed at controlling migraine episodes have targeted key brainstem relay and modulatory nuclei. In this study, we evaluated the impact of respiratory-gated auricular vagal afferent nerve stimulation (RAVANS), a novel neuromodulatory intervention based on an existing transcutaneous vagus nerve stimulation approach, in the modulation of brainstem activity and connectivity in migraine patients. We applied 3T-functional magnetic resonance imaging with improved in-plane spatial resolution (2.62 × 2.62 mm) in episodic migraine (interictal) and age- and sex-matched healthy controls to evaluate brain response to RAVANS (gated to either inhalation or exhalation) and sham stimulation. We further investigated RAVANS modulation of tactile trigeminal sensory afference response in the brainstem using air-puff stimulation directed to the forehead during functional magnetic resonance imaging. Compared with sham and inhalatory-gated RAVANS (iRAVANS), exhalatory-gated RAVANS (eRAVANS) activated an ipsilateral pontomedullary region consistent with nucleus tractus solitarii (NTS). During eRAVANS, NTS connectivity was increased to anterior insula and anterior midcingulate cortex, compared with both sham and iRAVANS, in migraine patients. Increased connectivity was inversely correlated with relative time to the next migraine attack, suggesting clinical relevance to this change in connectivity. Poststimulation effects were also noted immediately after eRAVANS, as we found increased activation in putative pontine serotonergic (ie, nucleus raphe centralis) and noradrenergic (ie, locus coeruleus) nuclei in response to trigeminal sensory afference. Regulation of activity and connectivity of brainstem and cortical regions involved in serotonergic and noradrenergic regulation and pain modulation may constitute an underlying mechanism supporting beneficial clinical outcomes for eRAVANS applied for episodic migraine.

The Modulatory Effect of Acupuncture on the Activity of Locus Coeruleus Neuronal Cells: A Review

The Locus Coeruleus (LC) is a small collection of noradrenergic neurons located in the pons. In the brain, noradrenaline (NE) is primarily produced by noradrenergic cell groups in the LC, which is the largest group of noradrenergic neurons in the central nervous system. Acupuncture, including the electroacupuncture which is a modified acupuncture method, is known to be effective in various kinds of diseases, and the involvement of noradrenergic system in the central nervous system has been reported by previous studies. However, on whether acupuncture can modulate the LC neuronal cells activities, results vary from studies to studies. In this paper, we included twelve articles, which observed the effect of acupuncture on the activities of LC in humans and animals. Our study shows that, among twelve included studies, six reported decrease of LC activities, whereas six showed increase of LC activities after acupuncture treatment. Although it is difficult to draw a firm conclusion, the authors suggest that the difference of frequencies may play an important role in the modulatory effect of acupuncture on LC. Further studies are needed to clarify the precise mechanism of acupuncture on LC, as it can lead to a new therapeutic method for various LC-NE related diseases.

Acupuncture for the Prevention of Tension-Type Headache (2016)

Linde K, Allais G, Brinkhaus B, et al. Acupuncture for the prevention of tension-type headache.Cochrane Database Syst Rev2016, Issue 48. Art No.: CD007587. DOI: 10.1002/14651858.CD007587.pub2.

BACKGROUND

Acupuncture is often used for prevention of tension-type headache but its effectiveness is still controversial. This is an update of our Cochrane review originally published in Issue 1, 2009 of The Cochrane Library.

OBJECTIVES

To investigate whether acupuncture is (a) more effective than no prophylactic treatment/routine care only; (b) more effective than "sham" (placebo) acupuncture; and (c) as effective as other interventions in reducing headache frequency in adults with episodic or chronic tension-type headache.

SEARCH METHODS

We searched CENTRAL, MEDLINE, EMBASE, and AMED to 19 January 2016. We searched the World Health Organization (WHO) International Clinical Trials Registry Platform to 10 February 2016 for ongoing and unpublished trials.

SELECTION CRITERIA

We included randomized trials with a post-randomization observation period of at least eight weeks, which compared the clinical effects of an acupuncture intervention with a control (treatment of acute headaches only or routine care), a sham acupuncture intervention or another prophylactic intervention in adults with episodic or chronic tension-type headache.

DATA COLLECTION AND ANALYSIS

Two review authors checked eligibility; extracted information on participants, interventions, methods and results; and assessed study risk of bias and the quality of the acupuncture intervention. The main efficacy outcome measure was response (at least 50% reduction of headache frequency) after completion of treatment (three to four months after randomization). To assess safety/acceptability we extracted the number of participants dropping out due to adverse effects and the number of participants reporting adverse effects. We assessed the quality of the evidence using Grading of Recommendations Assessment, Development and Evaluation (GRADE).

MAIN RESULTS

Twelve trials (11 included in the previous version and one newly identified) with 2349 participants (median = 56, range: 10-1265) met the inclusion criteria. Acupuncture was compared with routine care or treatment of acute headaches only in two large trials (1265 and 207 participants), but they had quite different baseline headache frequency and management in the control groups. Neither trial was blinded but trial quality was otherwise high (low risk of bias). While effect size estimates of the two trials differed considerably, the proportion of participants experiencing at least 50% reduction of headache frequency was much higher in groups receiving acupuncture than in control groups (moderate quality evidence; trial 1: 302/629 (48%) versus 121/636 (19%); risk ratio (RR) = 2.5; 95% confidence interval (CI): 2.1-3.0; trial 2: 60/132 (45%) versus 3/75 (4%); RR = 11; 95% CI: 3.7-35). Long-term effects (beyond four months) were not investigated. Acupuncture was compared with sham acupuncture in seven trials of moderate- to high-quality (low risk of bias); five large studies provided data for one or more meta-analyses. Among participants receiving acupuncture, 205 of 391 (51%) had at least 50% reduction of headache frequency compared to 133 of 312 (43%) in the sham group after treatment (RR = 1.3; 95% CI: 1.09-1.5; four trials; moderate quality evidence). Results six months after randomization were similar. Withdrawals were low: 1 of 420 participants receiving acupuncture dropped out due to adverse effects and 0 of 343 receiving sham (six trials; low quality evidence). Three trials reported the number of participants reporting adverse effects: 29 of 174 (17%) with acupuncture versus 12 of 103 with sham (12%; odds ratio (OR) = 1.3; 95% CI: 0.60-2.7; low quality evidence). Acupuncture was compared with physiotherapy, massage, or exercise in four trials of low to moderate quality (high risk of bias); study findings were inadequately reported. No trial found a significant superiority of acupuncture and for some outcomes the results slightly favored the comparison therapy. None of these trials reported the number of participants dropping out due to adverse effects or the number of participants reporting adverse effects. Overall, the quality of the evidence assessed using GRADE was moderate or low, downgraded mainly due to a lack of blinding and variable effect sizes. AUTHORS׳ CONCLUSIONS: The available results suggest that acupuncture is effective for treating frequent episodic or chronic tension-type headaches, but further trials-particularly comparing acupuncture with other treatment options-are needed.

The Effectiveness of Emotional Freedom Techniques in the Treatment of Posttraumatic Stress Disorder: A Meta-Analysis

BACKGROUND

Over the past two decades, growing numbers of clinicians have been utilizing emotional freedom techniques (EFT) in the treatment of posttraumatic stress disorder (PTSD), anxiety, and depression. Randomized controlled trials (RCTs) have shown encouraging outcomes for all three conditions.

OBJECTIVE

To assess the efficacy of EFT in treating PTSD by conducting a meta-analysis of existing RCTs.

METHODS

A systematic review of databases was undertaken to identify RCTs investigating EFT in the treatment of PTSD. The RCTs were evaluated for quality using evidence-based standards published by the American Psychological Association Division 12 Task Force on Empirically Validated Therapies. Those meeting the criteria were assessed using a meta-analysis that synthesized the data to determine effect sizes. While uncontrolled outcome studies were excluded, they were examined for clinical implications of treatment that can extend knowledge of this condition.

RESULTS

Seven randomized controlled trials were found to meet the criteria and were included in the meta-analysis. A large treatment effect was found, with a weighted Cohen׳s d = 2.96 (95% CI: 1.96-3.97, P < .001) for the studies that compared EFT to usual care or a waitlist. No treatment effect differences were found in studies comparing EFT to other evidence-based therapies such as eye movement desensitization and reprocessing (EMDR; 1 study) and cognitive behavior therapy (CBT; 1 study).

CONCLUSIONS

The analysis of existing studies showed that a series of 4-10 EFT sessions is an efficacious treatment for PTSD with a variety of populations. The studies examined reported no adverse effects from EFT interventions and showed that it can be used both on a self-help basis and as a primary evidence-based treatment for PTSD.

Evidence of a Synergistic Effect of Acupoint Combination: A Resting-State Functional Magnetic Resonance Imaging Study

Objective: This study aimed to find evidence of a synergistic effect of acupoint combinations by analyzing different brain regions activated after acupuncture at different acupoint combinations.

Methods: A total of 57 healthy subjects were randomly distributed into three groups: LR3 plus KI3 acupoints, LR3 plus sham acupoint, or LR3 alone. They underwent a magnetic resonance imaging scan before and after acupuncture. The amplitude of low-frequency fluctuation (ALFF) and regional homogeneity (ReHo) values of different brain regions were analyzed to observe changes in brain function.

Results: ALFF and ReHo produced an activated area in the cerebellum posterior lobe after acupuncture at LR3 plus KI3 acupoints versus LR3 alone. ALFF and ReHo revealed altered activity in Brodmann area 10 (BA10), BA18, and brainstem pons after acupuncture at LR3 plus sham acupoint compared with at LR3 alone. A comparison of acupuncture at LR3 plus KI3 acupoints with LR3 plus sham acupoint demonstrated an increase in BA6 of ALFF and a downregulation of ReHo.

Conclusions: The increased number of brain regions with altered brain activity after acupuncture at acupoint combinations versus a single acupoint are evidence of the synergistic effect of acupoint combinations. BA6 was significantly activated after acupuncture at LR3 plus KI3 acupoints compared with at LR3 plus sham acupoint, suggesting that BA6 is the specific region of synergistic effect of acupoint combinations of LR3 plus KI3 acupoints. Affected brain regions were different between acupuncture at LR3 plus sham acupoint and LR3 alone, which indicates that the sham acupoint may have some psychological effect. However, the specific mechanism of acupoint combinations requires further research.

Reduced insula habituation associated with amplification of trigeminal brainstem input in migraine

Background Impaired sensory processing in migraine can reflect diminished habituation, increased activation, or even increased gain or amplification of activity from the primary synapse in the brainstem to higher cortical/subcortical brain regions. Methods We scanned 16 episodic migraine (interictal) and 16 healthy controls (cross-sectional study), and evaluated brain response to innocuous air-puff stimulation over the right forehead in the ophthalmic nerve (V₁) trigeminal territory. We further evaluated habituation, and cortical/subcortical amplification relative to spinal trigeminal nucleus (Sp5) activation. Results Migraine subjects showed greater amplification from Sp5 to the posterior insula and hypothalamus. In addition, while controls showed habituation to repetitive sensory stimulation in all activated cortical regions (e.g. the bilateral posterior insula and secondary somatosensory cortices), for migraine subjects, habituation was not found in the posterior insula. Moreover, in migraine, the habituation slope was correlated with the amplification ratio in the posterior insula and secondary somatosensory cortex, i.e. greater amplification was associated with reduced habituation in these regions. Conclusions These findings suggest that in episodic migraine, amplified information processing from spinal trigeminal relay nuclei is linked to an impaired habituation response. This phenomenon was localized in the posterior insula, highlighting the important role of this structure in mechanisms supporting altered sensory processing in episodic migraine.

Functional Connectivity Modulation by Acupuncture in Patients with Bell's Palsy

Bell's palsy (BP), an acute unilateral facial paralysis, is frequently treated with acupuncture in many countries. However, the mechanism of treatment is not clear so far. In order to explore the potential mechanism, 22 healthy volunteers and 17 BP patients with different clinical duration were recruited. The resting-state functional magnetic resonance imaging scans were conducted before and after acupuncture at LI4 (Hegu), respectively. By comparing BP-induced functional connectivity (FC) changes with acupuncture-induced FC changes in the patients, the abnormal increased FC that could be reduced by acupuncture was selected. The FC strength of the selected FC at various stages was analyzed subsequently. Our results show that FC modulation of acupuncture is specific and consistent with the tendency of recovery. Therefore, we propose that FC modulation by acupuncture may be beneficial to recovery from the disease.

The Status of the Quality Control in Acupuncture-Neuroimaging Studies

Using neuroimaging techniques to explore the central mechanism of acupuncture gains increasing attention, but the quality control of acupuncture-neuroimaging study remains to be improved. We searched the PubMed Database during 1995 to 2014. The original English articles with neuroimaging scan performed on human beings were included. The data involved quality control including the author, sample size, characteristics of the participant, neuroimaging technology, and acupuncture intervention were extracted and analyzed. The rigorous inclusion and exclusion criteria are important guaranty for the participants' homogeneity. The standard operation process of acupuncture and the stricter requirement for acupuncturist play significant role in quality control. More attention should be paid to the quality control in future studies to improve the reproducibility and reliability of the acupuncture-neuroimaging studies.

Altered periaqueductal gray resting state functional connectivity in migraine and the modulation effect of treatment

The aims of this study were to 1) compare resting state functional connectivity (rs-fc) of the periaqueductal gray (PAG), a key region in the descending pain modulatory system (DPMS) between migraine without aura (MwoA) patients and healthy controls (HC), and 2) investigate how an effective treatment can influence the PAG rs-fc in MwoA patients. One hundred MwoA patients and forty-six matched HC were recruited. Patients were randomized to verum acupuncture, sham acupuncture, and waiting list groups. Resting state fMRI data were collected and seed based functional connectivity analysis was applied. Compared with HC, MwoA patients showed reduced rs-fc between the PAG and rostral anterior cingulate cortex/medial prefrontal cortex (rACC/mPFC), key regions in the DPMS and other pain related brain regions. The reduced rs-fc between the PAG and rACC/mPFC was associated with increased migraine headache intensity at the baseline. After treatments, rs-fc between the PAG and the rACC in MwoA patients significantly increased. The changes of rs-fc among the PAG, rACC and ventral striatum were significantly associated with headache intensity improvement. Impairment of the DPMS is involved in the neural pathophysiology of migraines. Impaired DPMS in migraine patients can be normalized after effective treatment.

Exploring Self-Reported Benefits of Auricular Acupuncture Among Veterans With Posttraumatic Stress Disorder

PURPOSE

Auricular acupuncture treatments are becoming increasingly available within military treatment facilities, resulting in an expansion of nonpharmacologic treatment options available to veterans with posttraumatic stress disorder (PTSD). This study aimed to explore the self-reported benefits of auricular acupuncture treatments for veterans living with PTSD.

DESIGN

A qualitative research methodology, thematic content analysis, was used to analyze data.

METHOD

Seventeen active duty veterans with PTSD provided written comments to describe their experiences and perceptions after receiving a standardized auricular acupuncture regimen for a 3-week period as part of a pilot feasibility study.

FINDINGS

A variety of symptoms experienced by veterans with PTSD were improved after receiving auricular acupuncture treatments. Additionally, veterans with PTSD were extremely receptive to auricular acupuncture treatments. Four themes emerged from the data: (1) improved sleep quality, (2) increased relaxation, (3) decreased pain, and (4) veterans liked/loved the auricular acupuncture treatments.

CONCLUSIONS

Veterans with PTSD reported numerous benefits following auricular acupuncture treatments. These treatments may facilitate healing and recovery for veterans with combat-related PTSD, although further investigations are warranted into the mechanisms of action for auricular acupuncture in this population.

Acupuncture at KI3 in healthy volunteers induces specific cortical functional activity: an fMRI study

Background

Using functional magnetic resonance imaging (fMRI), we determined brain regions that were activated/deactivated more by acupuncture at Taixi (KI3) than by non-acupoint or sham acupuncture.

Methods

A total of 30 healthy volunteers were randomly divided into a KI3 group (15 subjects) and non-acupoint group (15 subjects). Subjects in KI3 group received a sham acupuncture and then a real acupuncture, fMRI was performed before and after sham acupuncture as well as after ture acupuncture. Subjects in non-acupoint group received a ture acupuncture and the fMRI was performed before and after ture acupuncture. The fMRI data obtained were successively analyzed using DPARSF2.3 and REST1.8 software, yielding regional homogeneity (ReHo) and amplitude of low frequency fluctuations (ALFF) values.

Results

Compared with sham acupuncture, ALFF values were higher in Brodmann area (BA) 10 and lower in BA7 and BA18. ReHo values after real acupuncture at KI3 were higher in the right sub-lobar region and BA10 and were lower in BA31. Compared with the changes before and after real acupuncture at non-acupoint, the changes at KI3 showed higher ALFF valued in the left cerebellum posterior lobe, BA10, BA39, BA31 and decreased ALFF was observed in the BA18, BA19 and BA40; and higher ReHo values were shown in left cerebellum posterior lobe pyramis, left cerebellum anterior lobe. BA37, BA10, BA39, BA31 and lower ReHo values were shown in BA18 and BA31.

Conclusion

Acupuncture at KI3 has a specific effect on certain brain regions associated with perception, body movement, spirit, and association. Additionally, visual and auditory cortices were affected, which may be related to the clinical applications of KI3 acupuncture in auditory and cognitive disorders, hypomnesis, loss of concentration, and the loss of ability to work and learn.

Trial registration

The research ethics committee was achieved at 01/08/2012, the NO. was ChiECRCT-2012011. Website for Clinical Trial Registration: http://www.chictr.org.cn/showproj.aspx?proj=7123.

This study was registered at www.chictr.org, the Clinical Trial Registration Number was ChiCTR-TRC-12002427, and the registration number was achieved at 18/08/2012. The name of IRB that provided approval for the study and clearly state is Chinese Clinical Trail Registry.

The Expression Patterns of c-Fos and c-Jun Induced by Different Frequencies of Electroacupuncture in the Brain

To investigate patterns of c-Fos and c-Jun expression induced by different frequencies of electroacupuncture (EA) in the brain, goats were stimulated by EA of 0, 2, 60, or 100 Hz at a set of "Baihui, Santai, Ergen, and Sanyangluo" points for 30 min. The pain threshold was measured using the potassium iontophoresis method. The levels of c-Fos and c-Jun were determined with Streptavidin-Biotin Complex immunohistochemistry. The results showed that the pain threshold induced by 60 Hz was 82.2% higher (P < 0.01) than that by 0, 2, or 100 Hz (6.5%, 35.2%, or 40.9%). EA induced increased c-Fos and c-Jun expression in most analgesia-related nuclei and areas in the brain. Sixty Hz EA increased more c-Fos or c-Jun expression than 2 Hz or 100 Hz EA in all the measured nuclei and areas except for the nucleus accumbens, the area septalis lateralis, the caudate nucleus, the nucleus amygdala basalis, and the locus coeruleus, in which c-Fos or c-Jun expressions induced by 60 Hz EA did not differ from those by 2 Hz or 100 Hz EA. It was suggested that 60 Hz EA activated more extensive neural circuits in goats, which may contribute to optimal analgesic effects.

Functional MRI of the Brainstem: Common Problems and their Solutions

Functional magnetic resonance imaging (fMRI) of the brainstem is a relatively young field that is rapidly evolving. While it is still difficult to obtain usable fMRI signals from this complicated brain region, the past few years have seen a number of important advances that bring us closer to routine application of this method in the clinical and scientific setting. This review gives an overview of the technical capabilities and limitations of brainstem fMRI. It explains the major brainstem-specific problems and gives advice on how to avoid or counteract them. In particular, I discuss how spatial resolution issues can be overcome by using appropriate sequences, coils, and spatial preprocessing, how the effects of physiological noise can be mitigated by noise modeling and spatial masking, and how the functional heterogeneity of brainstem nuclei needs to be taken into account, when planning a study. Solving these common problems is a prerequisite for any scientist or clinician interested in applying fMRI to measure brainstem activity.

The effects of acupuncture treatment on the right frontoparietal network in migraine without aura patients

BACKGROUND

Functional and structural abnormalities in resting-state brain networks in migraine patients have been confirmed by previous functional magnetic resonance imaging (fMRI) studies. However, few studies focusing on the neural responses of therapeutic treatment on migraine have been conducted. In this study, we tried to examined the treatment-related effects of standard acupuncture treatment on the right frontoparietal network (RFPN) in migraine patients.

METHODS

A total of 12 migraine without aura (MWoA) patients were recruited to undergo resting-state fMRI scanning and were rescanned after 4 weeks standard acupuncture treatment. Another 12 matched healthy control (HC) subjects underwent once scanning for comparison. We analyzed the functional connectivity of the RFPN between MWoA patients and HC subjects before treatment and that of the MWoA patients before and after treatment. Diffusion tensor images (DTI) data analyzing was also performed to detect fiber-related treatment responses.

RESULTS

We observed significantly decreased FC in the RFPN and that the decreased FC could be reversed by acupuncture treatment. The changes of FC in MWoA patients was negatively correlated with the decrease of visual analogue scale (VAS) scores after treatment. This study indicated that acupuncture treatment for MWoA patients was associated with normalizing effects on the intrinsic decreased FC of the RFPN.

CONCLUSIONS

Our study provided new insights into the treatment-related neural responses in MWoA patients and suggested potential functional pathways for the evaluation of treatment in MWoA patients. Future studies are still in need to confirm the current results and to elucidate the complex neural mechanisms of acupuncture treatment.

Neural mechanisms of acupuncture as revealed by fMRI studies

As an ancient therapeutic method, acupuncture has been used to treat many diseases as an adjunctive therapy. However, its clinical efficacy remains controversial and the neural mechanisms have not been well understood. Accumulating studies have revealed that fMRI has made it possible to study brain responses to acupuncture. This review aims to provide scientific evidence to support the notion and discuss how these findings contribute to the neural mechanisms of acupuncture.

Differential cerebral response to somatosensory stimulation of an acupuncture point vs. two non-acupuncture points measured with EEG and fMRI

Acupuncture can be regarded as a complex somatosensory stimulation. Here, we evaluate whether the point locations chosen for a somatosensory stimulation with acupuncture needles differently change the brain activity in healthy volunteers. We used EEG, event-related fMRI, and resting-state functional connectivity fMRI to assess neural responses to standardized needle stimulation of the acupuncture point ST36 (lower leg) and two control point locations (CP1 same dermatome, CP2 different dermatome). Cerebral responses were expected to differ for stimulation in two different dermatomes (CP2 different from ST36 and CP1), or stimulation at the acupuncture point vs. the control points. For EEG, mu rhythm power increased for ST36 compared to CP1 or CP2, but not when comparing the two control points. The fMRI analysis found more pronounced insula and S2 (secondary somatosensory cortex) activation, as well as precuneus deactivation during ST36 stimulation. The S2 seed-based functional connectivity analysis revealed increased connectivity to right precuneus for both comparisons, ST36 vs. CP1 and ST36 vs. CP2, however in different regions. Our results suggest that stimulation at acupuncture points may modulate somatosensory and saliency processing regions more readily than stimulation at non-acupuncture point locations. Also, our findings suggest potential modulation of pain perception due to acupuncture stimulation.

Disrupted functional connectivity of the periaqueductal gray in chronic low back pain

Chronic low back pain is a common neurological disorder. The periaqueductal gray (PAG) plays a key role in the descending modulation of pain. In this study, we investigated brain resting state PAG functional connectivity (FC) differences between patients with chronic low back pain (cLBP) in low pain or high pain condition and matched healthy controls (HCs). PAG seed based functional connectivity (FC) analysis of the functional MR imaging data was performed to investigate the difference among the connectivity maps in the cLBP in the low or high pain condition and HC groups as well as within the cLBP at differing endogenous back pain intensities. Results showed that FC between the PAG and the ventral medial prefrontal cortex (vmPFC)/rostral anterior cingulate cortex (rACC) increased in cLBP patients compared to matched controls. In addition, we also found significant negative correlations between pain ratings and PAG–vmPFC/rACC FC in cLBP patients after pain-inducing maneuver. The duration of cLBP was negatively correlated with PAG–insula and PAG–amygdala FC before pain-inducing maneuver in the patient group. These findings are in line with the impairments of the descending pain modulation reported in patients with cLBP. Our results provide evidence showing that cLBP patients have abnormal FC in PAG centered pain modulation network during rest.

Our results provide evidence showing that cLBP patients have abnormal FC in PAG centered pain modulation network during rest, which might have important treatment implications.

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cLBP patients exhibited enhanced PAG–mPFC coupling.

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cLBP duration was correlated with PAG–mPFC coupling.

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Pain intensity was correlated with PAG–insula and PAG–amygdala coupling.

Prolonged repeated acupuncture stimulation induces habituation effects in pain-related brain areas: an FMRI study

Most previous studies of brain responses to acupuncture were designed to investigate the acupuncture instant effect while the cumulative effect that should be more important in clinical practice has seldom been discussed. In this study, the neural basis of the acupuncture cumulative effect was analyzed. For this experiment, forty healthy volunteers were recruited, in which more than 40 minutes of repeated acupuncture stimulation was implemented at acupoint Zhusanli (ST36). Three runs of acupuncture fMRI datasets were acquired, with each run consisting of two blocks of acupuncture stimulation. Besides general linear model (GLM) analysis, the cumulative effects of acupuncture were analyzed with analysis of covariance (ANCOVA) to find the association between the brain response and the cumulative duration of acupuncture stimulation in each stimulation block. The experimental results showed that the brain response in the initial stage was the strongest although the brain response to acupuncture was time-variant. In particular, the brain areas that were activated in the first block and the brain areas that demonstrated cumulative effects in the course of repeated acupuncture stimulation overlapped in the pain-related areas, including the bilateral middle cingulate cortex, the bilateral paracentral lobule, the SII, and the right thalamus. Furthermore, the cumulative effects demonstrated bimodal characteristics, i.e. the brain response was positive at the beginning, and became negative at the end. It was suggested that the cumulative effect of repeated acupuncture stimulation was consistent with the characteristic of habituation effects. This finding may explain the neurophysiologic mechanism underlying acupuncture analgesia.

Cerebral blood flow-based evidence for mechanisms of low- versus high-frequency transcutaneous electric acupoint stimulation analgesia: a perfusion fMRI study in humans

Brain activities in response to acupuncture have been investigated in multiple studies; however, the neuromechanisms of low- and high-frequency transcutaneous electric acupoint stimulation (TEAS) analgesia are unclear. This work aimed to investigate how brain activity and the analgesic effect changed across 30-min low- versus high-frequency TEAS. Forty-six subjects received a 30-min 2, 100-Hz TEAS or mock TEAS (MTEAS) treatment on both behavior test and functional magnetic resonance imaging (fMRI) scan days. On the behavior test day, the pain thresholds and pain-related negative emotional feeling ratings were tested five times - at 4.5min before treatment, at 10, 20, and 30min during treatment and 4.5min after the treatment. On the fMRI scan day, to match the time-points in the behavioral testing session, the cerebral blood flow (CBF) signals were collected and incorporated with five independent runs before, during and after the treatment, each lasting 4.5min. The analgesic effect was observed in both the TEAS groups; the analgesic affect was not found in the MTEAS group. The effect started at 20min during the treatment and was maintained until the after-treatment states. In both TEAS groups, the regional CBF revealed a trend of early activation with later inhibition; also, a positive correlation between analgesia and the regional CBF change was observed in the anterior insula in the early stage, whereas a negative relationship was found in the parahippocampal gyrus in the later stage. The TEAS analgesia was specifically associated with the default mode network and other cortical regions in the 2-Hz TEAS group, ventral striatum and dorsal anterior cingulate cortex in the 100-Hz TEAS group, respectively. These findings suggest that the mechanisms of low- and high-frequency TEAS analgesia are distinct and partially overlapped, and they verify the treatment time as a notable factor for acupuncture studies.

Manipulation of and sustained effects on the human brain induced by different modalities of acupuncture: an fMRI study

The javascript:void(0)manipulation and sustained effects of acupuncture have been investigated in multiple studies, but several findings are inconsistent with one another. One possible explanation for these discrepancies is that different modalities of acupuncture were utilized in these studies. In the present study, we investigated both the manipulation and sustained effects of acupuncture in different modalities, including manual acupuncture (MA), electroacupuncture (EA) and transcutaneous electrical acupoint stimulation (TEAS). MA, EA, TEAS and sensory control stimulation were applied to 18 healthy subjects, and combined block-designed and resting-state fMRI scans were performed. In analyzing these data, the block-designed datasets were used to assess the manipulation effect by employing a modified general linear model. The data from the resting states, before and after stimulation, were used to explore the brain networks involved in the sustained effect. The results showed that the two 1-min stimulation periods produced similar activation patterns in the sensory control with positive activation in the sensorimotor areas and negative activation in the default mode areas. Although similar patterns could be detected in the first stimulation period in MA, EA and TEAS, no positive activation result was observed in the second stimulation period, and EA showed a more extensive deactivation compared to MA and TEAS. Additionally, all three of the modalities of acupuncture stimulation could increase the instinct brain network in rest. A more secure and spatially extended connectivity of the default mode network was observed following MA and EA, and TEAS specifically increased the functional connectivity in the sensorimotor network. The present study suggested that different brain mechanisms might be recruited in different acupuncture modalities. In addition, the findings from our work could provide methodological information for further research into the mechanism of acupuncture.

Acupuncture-evoked response in somatosensory and prefrontal cortices predicts immediate pain reduction in carpal tunnel syndrome

The linkage between brain response to acupuncture and subsequent analgesia remains poorly understood. Our aim was to evaluate this linkage in chronic pain patients with carpal tunnel syndrome (CTS). Brain response to electroacupuncture (EA) was evaluated with functional MRI. Subjects were randomized to 3 groups: (1) EA applied at local acupoints on the affected wrist (PC-7 to TW-5), (2) EA at distal acupoints (contralateral ankle, SP-6 to LV-4), and (3) sham EA at nonacupoint locations on the affected wrist. Symptom ratings were evaluated prior to and following the scan. Subjects in the local and distal groups reported reduced pain. Verum EA produced greater reduction of paresthesia compared to sham. Compared to sham EA, local EA produced greater activation in insula and S2 and greater deactivation in ipsilateral S1, while distal EA produced greater activation in S2 and deactivation in posterior cingulate cortex. Brain response to distal EA in prefrontal cortex (PFC) and brain response to verum EA in S1, SMA, and PFC were correlated with pain reduction following stimulation. Thus, while greater activation to verum acupuncture in these regions may predict subsequent analgesia, PFC activation may specifically mediate reduced pain when stimulating distal acupoints.

Oscillatory serotonin function in depression

Oscillations in brain activities with periods of minutes to hours may be critical for normal mood behaviors. Ultradian (faster than circadian) rhythms of mood behaviors and associated central nervous system activities are altered in depression. Recent data suggest that ultradian rhythms in serotonin (5HT) function also change in depression. In two separate studies, 5HT metabolites in cerebrospinal fluid (CSF) were measured every 10 min for 24 h before and after chronic antidepressant treatment. Antidepressant treatments were associated with enhanced ultradian amplitudes of CSF metabolite levels. Another study used resting-state functional magnetic resonance imaging (fMRI) to measure amplitudes of dorsal raphé activation cycles following sham or active dietary depletions of the 5HT precursor (tryptophan). During depletion, amplitudes of dorsal raphé activation cycles increased with rapid 6 s periods (about 0.18 Hz) while functional connectivity weakened between dorsal raphé and thalamus at slower periods of 20 s (0.05 Hz). A third approach studied MDMA (ecstasy, 3,4-methylenedioxy-N-methylamphetamine) users because of their chronically diminished 5HT function compared with non-MDMA polysubstance users (Karageorgiou et al., 2009). Compared with a non-MDMA using cohort, MDMA users showed diminished fMRI intra-regional coherence in motor regions along with altered functional connectivity, again suggesting effects of altered 5HT oscillatory function. These data support a hypothesis that qualities of ultradian oscillations in 5HT function may critically influence moods and behaviors. Dysfunctional 5HT rhythms in depression may be a common endpoint and biomarker for depression, linking dysfunction of slow brain network oscillators to 5HT mechanisms affected by commonly available treatments. 5HT oscillatory dysfunction may define illness subtypes and predict responses to serotonergic agents. Further studies of 5HT oscillations in depression are indicated.