Guangyu Zhou

Regional homogeneity abnormalities in patients with interictal migraine without aura: a resting-state study.

Previous studies have provided evidence of structural and task‐related functional changes in the brains of patients with migraine without aura. Resting‐state brain activity in patients with migraine provides clues to the pathophysiology of the disease. However, few studies have focused on the resting‐state abnormalities in patients with migraine without aura. In the current study, we employed a data‐driven method, regional homogeneity (ReHo), to analyze the local features of spontaneous brain activity in patients with migraine without aura during the resting state. Twenty‐six patients with migraine without aura and 26 age‐, education‐ and gender‐matched healthy volunteers participated in this study. Compared with healthy controls, patients with migraine without aura showed a significant decrease in ReHo values in the right rostral anterior cingulate cortex (rACC), the prefrontal cortex (PFC), the orbitofrontal cortex (OFC) and the supplementary motor area (SMA). In addition, we found that ReHo values were negatively correlated with the duration of disease in the right rACC and PFC. Our results suggest that the resting‐state abnormalities of these regions may be associated with functional impairments in pain processing in patients with migraine without aura. We hope that our results will improve the understanding of migraine. Copyright

Partial correlation investigation on the default mode network involved in acupuncture: An fMRI study

Certain clinical reports and researches have shown that acupuncture effects can sustain a period during the post-stimulation state, and modulate the default mode network (DMN). In this study, partial correlation approach was utilized to investigate whether or not electro-acupuncture stimulation (EAS) at the three acupoints (GB37 (Guangming), BL60 (Kunlun) and KI8 (Jiaoxin)) and one sham point on the left leg modulated the DMN and how to change the intrinsic connectivity of the DMN. The results indicated that DMN could be modulated after EAS, and there existed different modulation patterns of the four points. Meanwhile, we found that the posterior cingulate cortex and precuneus (PCC/pC) strongly interacted with other nodes during the pre- and post-stimulation states. The correlation was interrupted between the PCC/pC and anterior cingulate cortex (ACC). The orbital prefrontal cortex (OFC) negatively interacted with the left medial temporal cortex (lMTC) at the acupoints. We suggested that the distinct modulation patterns to the DMN attributed to the different effects evoked by the three acupoints and one sham point.

Axonal loss of white matter in migraine without aura: a tract-based spatial statistics study.

Aim Multiple diffusion tensor imaging (DTI) derived indices may help to deduce the pathophysiological type of white matter (WM) changes and provide more specific biomarkers of WM neuropathology in the whole brain of migraine patients without aura (MWoA). Methods Twenty MWoA and 20 age-, education- and gender-matched healthy volunteers participated in this study. Tract-based spatial statistics (TBSS) was employed to investigate the WM abnormalities in MWoA by integrating multiple indices, including fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (AD). Results Compared with healthy controls, MWoA showed significantly lower FA, MD and AD in multiple brain regions, whereas no difference in RD was observed. Specifically, the overlap among the lower FA, MD, and AD was found in the genu, body, and splenium part of the corpus callosum (CC), the right anterior limb of the internal capsule (ALIC) and the posterior limb of the internal capsule (PLIC) in MWoA compared with healthy controls. Additionally, some of the above WM findings were significantly correlated with duration and headache frequency in MWoA. Conclusion Given that decreased AD may suggest axonal loss, our findings may reveal axonal loss in MWoA.

Combining spatial and temporal information to explore function-guide action of acupuncture using fMRI

To investigate the brain response patterns of modulation of GB37 (Guangming) and KI8 (Jiaoxin).

White-Matter Microstructural Changes in Functional Dyspepsia: A Diffusion Tensor Imaging Study

OBJECTIVES:Recent neuroimaging studies have identified brain microstructural changes in patients with functional gastrointestinal disorders, especially in irritable bowel syndrome. However, whether the microstructure is changed in patients with postprandial distress syndrome (PDS) remains elusive. Therefore, the present study was aimed to examine the white-matter (WM) microstructural changes in patients with PDS.METHODS:Diffusion tensor imaging (DTI) was performed on 36 PDS patients recruited according to the Rome III criteria and 36 healthy controls. Tract-based spatial statistics were adopted to examine the between-group differences in DTI measures including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity, and radial diffusivity (RD). The correlations between DTI measures and clinical variables were evaluated using a non-parametric permutation-based test. Multiple comparisons were corrected using the threshold-free cluster enhancement method.RESULTS:The patient group showed increased FA along with reduced MD and RD in multiple WM tracts, including the corona radiata, internal capsule, posterior thalamic radiation, corpus callosum, external capsule, sagittal stratum, and superior longitudinal fasciculus (P<0.05, corrected). The inclusion of anxiety and depression as covariates abolished the between-group difference in these tracts with the exception of the corona radiata. The DTI measures were not found to be correlated with the severity of symptoms or the duration of disease (P>0.05, corrected).CONCLUSIONS:Our findings have provided preliminary evidence of WM microstructural changes in patients with PDS. Part of the changes could be accounted for by a higher level of psychosocial distress in the patient group.

The hybrid GLM-ICA investigation on the neural mechanism of acupoint ST36: An fMRI study

Ample clinical reports and neuroimaging studies have demonstrated that the acupuncture has sustained effects after manipulation. However, most previous fMRI studies of acupuncture have paid little attention to this issue, only investigating on the manipulation effects. In the current study, we attempted to explore both acupuncture effects, which have positive influence to therapeutic efficiency, to reveal the neural mechanism of acupuncture. This paper combined the conventional general linear model (GLM) and independent component analysis (ICA) to study the topography and the temporal feature of brain activity to detect the brain responses to stimulation at ST36 (Zusanli) and a sham acupoint. The results showed that the manipulation-related effects and the sustained acupuncture effects separately induced statistically significant increases/decreases in the cortical-subcortical areas, including the anterior cingulate cortex (ACC), ventrolateral prefrontal cortex (VLPFC), supplementary motor area (SMA) primary/secondary somatosensory cortex (SI/SII), occipital cortices and midbrain. Our findings suggested that the analgesia effects of ST36 integrated sophisticated physiological and psychological procedures. In addition, our results have shed light on methodology in acupuncture research.

Identifying Neural Patterns of Functional Dyspepsia Using Multivariate Pattern Analysis: A Resting-State fMRI Study

Background Previous imaging studies on functional dyspepsia (FD) have focused on abnormal brain functions during special tasks, while few studies concentrated on the resting-state abnormalities of FD patients, which might be potentially valuable to provide us with direct information about the neural basis of FD. The main purpose of the current study was thereby to characterize the distinct patterns of resting-state function between FD patients and healthy controls (HCs). Methodology/Principal Findings Thirty FD patients and thirty HCs were enrolled and experienced 5-mintue resting-state scanning. Based on the support vector machine (SVM), we applied multivariate pattern analysis (MVPA) to investigate the differences of resting-state function mapped by regional homogeneity (ReHo). A classifier was designed by using the principal component analysis and the linear SVM. Permutation test was then employed to identify the significant contribution to the final discrimination. The results displayed that the mean classifier accuracy was 86.67%, and highly discriminative brain regions mainly included the prefrontal cortex (PFC), orbitofrontal cortex (OFC), supplementary motor area (SMA), temporal pole (TP), insula, anterior/middle cingulate cortex (ACC/MCC), thalamus, hippocampus (HIPP)/parahippocamus (ParaHIPP) and cerebellum. Correlation analysis revealed significant correlations between ReHo values in certain regions of interest (ROI) and the FD symptom severity and/or duration, including the positive correlations between the dmPFC, pACC and the symptom severity; whereas, the positive correlations between the MCC, OFC, insula, TP and FD duration. Conclusions These findings indicated that significantly distinct patterns existed between FD patients and HCs during the resting-state, which could expand our understanding of the neural basis of FD. Meanwhile, our results possibly showed potential feasibility of functional magnetic resonance imaging diagnostic assay for FD.

White matter integrity affected by depressive symptoms in migraine without aura: a tract-based spatial statistics study

Previous studies have proven that migraine and depression are bidirectionally linked. However, few studies have investigated white matter (WM) integrity affected by depressive symptoms in patients suffering from migraine without aura (MWoA). Forty patients with MWoA were divided into two groups according to their self‐rating depression scale (SDS) score in the present study, including 20 in the SDS (+) (SDS > 49) group and 20 in the SDS (−) (SDS ≤ 49) group. Forty healthy participants were also recruited as the control group. Tract‐based spatial statistics analyses with multiple diffusion tensor imaging‐derived indices [fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), axial diffusivity (AD)] were employed collectively to investigate WM integrity between all patients with MWoA and all healthy controls, between each subgroup (SDS (−) group and SDS (+) group) and healthy controls, and between the SDS (−) and SDS (+) groups. Compared with healthy controls, decreased AD was shown in several WM tracts of the whole MWoA group, SDS (−) group and SDS (+) group. In addition, compared with the SDS (−) group, the SDS (+) group showed decreased FA and increased MD and RD, with conserved AD, including the genu, body and splenium of the corpus callosum, bilateral superior longitudinal fasciculi, the right anterior corona radiata and some other WM tracts, similar to previous findings in depression disorder. Furthermore, mean FA and RD in some of the above‐mentioned WM tracts in the SDS (+) group were correlated significantly with SDS scores, including the genu and splenium of the corpus callosum, the right anterior corona radiata and the superior longitudinal fasciculi. Our results suggest that WM integrity may be affected by both depression symptoms (more sensitive as RD) and migraine (more sensitive as AD). The findings may serve as a sensitive biomarker of depression severity in MWoA. Copyright

Alterations of the default mode network in functional dyspepsia patients: a resting-state fmri study

Increasing brain imaging studies have emphasized the role of regional brain activity abnormalities in functional dyspepsia (FD) during the resting state. The goal of this study was to investigate the default mode network (DMN) in FD patients and healthy controls (HCs).

Increased interhemispheric resting-state functional connectivity in functional dyspepsia: a pilot study

Recent brain imaging studies have emphasized the role of regional brain activity abnormalities in the pathophysiology of functional dyspepsia (FD). However, whether the functional connectivity between brain regions is changed, especially between the cerebral hemispheres, in patients with FD remains unknown. Thus, the present study aimed to examine the interhemispheric resting‐state functional connectivity (RSFC) changes in patients with FD. Resting‐state functional MRI (fMRI) was performed in 26 patients with FD and in 20 matched healthy controls. An interhemispheric RSFC map was obtained by calculating the Pearson correlation (Fisher Z transformed) between each pair of homotopic voxel time series for each subject. The between‐group difference in interhemispheric RSFC was then examined at global and voxelwise levels separately. The global difference in interhemispheric RSFC between groups was tested using the independent two‐sample t‐test. Voxelwise comparisons were carried out using a permutation‐based nonparametric test, and multiple comparisons across space were corrected using the threshold‐free cluster enhancement (TFCE) method. The results showed that patients with FD had higher global interhemispheric RSFC than healthy controls (p < 0.01). Furthermore, voxelwise analysis revealed that patients with FD had increased interhemispheric RSFC in brain regions including the anterior cingulate cortex, insula and thalamus (p < 0.01, TFCE corrected). Our findings provide preliminary evidence of interhemispheric correlation abnormalities in patients with FD and contribute to a better understanding of the pathophysiology of the disease. Copyright