Bensheng Qiu

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.

Acupuncture-induced changes in functional connectivity of the primary somatosensory cortex varied with pathological stages of Bell's palsy.

Bell’s palsy is the most common cause of acute facial nerve paralysis. In China, Bell’s palsy is frequently treated with acupuncture. However, its efficacy and underlying mechanism are still controversial. In this study, we used functional MRI to investigate the effect of acupuncture on the functional connectivity of the brain in Bell’s palsy patients and healthy individuals. The patients were further grouped according to disease duration and facial motor performance. The results of resting-state functional MRI connectivity show that acupuncture induces significant connectivity changes in the primary somatosensory region of both early and late recovery groups, but no significant changes in either the healthy control group or the recovered group. In the recovery group, the changes also varied with regions and disease duration. Therefore, we propose that the effect of acupuncture stimulation may depend on the functional connectivity status of patients with Bell’s palsy.

Aberrant structural and functional connectivity in the salience network and central executive network circuit in schizophrenia

Consistent structural and functional abnormities have been detected in the salience network (SN) and the central-executive network (CEN) in schizophrenia. SN, known for its critical role in switching CEN and default-mode network (DMN) during cognitively demanding tasks, is proved to show aberrant regulation on the interaction between DMN and CEN in schizophrenia. However, it has not been elucidated whether there is a direct alteration of structural and functional connectivity between SN and CEN. 22 schizophrenia patients and 21 healthy controls were recruited for functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) in present study. The results show that schizophrenia patients had lower fractional anisotropy (FA) in right inferior long fasciculus (ILF), left inferior fronto-occipital fasciculus (IFOF) and callosal body than healthy controls. Significantly reduced functional connectivity was also found between right fronto-insular cortex (rFIC) and right posterior parietal cortex (rPPC). FA in right ILF was positively correlated with the functional connectivity of rFIC-rPPC. Therefore, we proposed a disruption of structural and functional connectivity and a positive anatomo-functional relationship in SN-CEN circuit, which might account for a core feature of schizophrenia.

Functional connectivity change of brain default mode network in breast cancer patients after chemotherapy

IntroductionComplaint about attention disorders is common among breast cancer patients who have undergone chemotherapy, which may be associated with the default mode network (DMN). To validate this hypothesis, we investigated the DMN functional connectivity (FC) change and its relationship with the attention function in breast cancer patients (BC) using resting-state functional magnetic resonance imaging (rs-fMRI).MethodsTwenty-two BC treated with chemotherapy and 22 healthy controls (HC) were recruited into this study. The FC between the DMN’s hubs and regions of the dorsal medial prefrontal cortex (dMPFC) and medial temporal lobe (MTL) subsystems was respectively calculated for each participant.ResultsThe statistical result showed significantly lower connectivity in dMPFC and MTL subsystems in the BC group. In addition, the partial correlation analysis result indicated that the low connectivity of some brain regions in MTL subsystem was correlated with attention dysfunction following BC chemotherapy.ConclusionThese results suggest that the functional disconnection in MTL subsystem of the DMN may have association with attention function of BC after chemotherapy.

Increasing functional connectivity of the anterior cingulate cortex during the course of recovery from bell's palsy

Bell’s palsy (BP), a unilateral and idiopathic palsy of the facial nerve, is a common disorder generally followed by a good natural recovery. The aim of this study was to investigate the relationship between the functional connectivity of the anterior cingulate cortex (ACC) and the recovery process of BP. Thirty-seven healthy volunteers and 67 patients were studied by functional MRI (fMRI). The seed regions of bilateral ACC were first extracted from the task-state fMRI data of healthy participants performing the task of mouth opening and closing. The connectivity of bilateral ACC was calculated from resting-state fMRI data of patients in whom only resting-state fMRI data were collected. The correlation between the strength of ACC’s connectivity with the duration (time course of disease) was computed by analysis of covariance. It was found that the functional connectivity of the ACC ipsilateral to the lesioned side was enforced as the duration increased. The enforced brain areas included the sensorimotor areas and the ACC contralateral to the palsy. It was suggested that enforced functional connectivity of ACC might be related to cortical reorganization, which is important in the process of BP recovery.

The Working Memory and Dorsolateral Prefrontal-Hippocampal Functional Connectivity Changes in Long-Term Survival Breast Cancer Patients Treated with Tamoxifen

Abstract Background: Tamoxifen is the most widely used drug for treating patients with estrogen receptor-sensitive breast cancer. There is evidence that breast cancer patients treated with tamoxifen exhibit cognitive dysfunction. However, the underlying neural mechanism remains unclear. The present study aimed to investigate the neural mechanisms underlying working memory deficits in combination with functional connectivity changes in premenopausal women with breast cancer who received long-term tamoxifen treatment. Methods: A total of 31 premenopausal women with breast cancer who received tamoxifen and 32 matched healthy control participants were included. The participants completed n-back tasks and underwent resting-state functional magnetic resonance imaging, which measure working memory performance and brain functional connectivity, respectively. A seed-based functional connectivity analysis within the whole brain was conducted, for which the dorsolateral prefrontal cortex was chosen as the seed region. Results: Our results indicated that the tamoxifen group had significant deficits in working memory and general executive function performance and significantly lower functional connectivity of the right dorsolateral prefrontal cortex with the right hippocampus compared with the healthy controls. There were no significant changes in functional connectivity in the left dorsolateral prefrontal cortex within the whole brain between the tamoxifen group and healthy controls. Moreover, significant correlations were found in the tamoxifen group between the functional connectivity strength of the dorsolateral prefrontal cortex with the right hippocampus and decreased working memory performance. Conclusion: This study demonstrates that the prefrontal cortex and hippocampus may be affected by tamoxifen treatment, supporting an antagonistic role of tamoxifen in the long-term treatment of breast cancer patients.

Executive Function Alternations of Breast Cancer Patients After Chemotherapy: Evidence From Resting-state Functional MRI.

RATIONALE AND OBJECTIVES Chemotherapy has many side effects on breast cancer patients, including cognition and other brain functions impairment, which can be studied using functional magnetic resonance imaging (fMRI). Our study aimed at investigating the executive function alternations of breast cancer patients after chemotherapy using resting-state fMRI. MATERIALS AND METHODS This study included 32 breast cancer patients (BC group) and 24 control subjects (HC group). The functional connectivity of the dorsolateral prefrontal cortex (DLPFC) of the two groups was calculated from the resting-state fMRI data, and the correlation between the strength of the right DLPFCs connectivity and the behavior performance was analyzed with two-tailed Pearson correlative analysis. RESULTS Evaluation of the capability of processing various complex cognition events showed that the executive function of the BC group was impaired after chemotherapy in comparison with the HC group. The functional connectivities of the right DLPFC with the right inferior frontal gyrus, right medial frontal gyrus, and left superior temporal gyrus in the BC group were significantly decreased in comparison with those in the HC group, respectively. The executive deficits were found correlated with the functional connectivity between the right DLPFC and the right inferior frontal gyrus. Meantime, the functional connectivity from the right DLPFC to the right middle temporal gyrus and the precuneus was compensatorily increased in the BC group, respectively. CONCLUSIONS These findings suggest that breast cancer patients after chemotherapy demonstrate executive control impairment, and provide evidence that the observed defects are correlated with alternations in the executive network of the brain.

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

Bells 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 attention network changes in breast cancer patients receiving neoadjuvant chemotherapy: Evidence from an arterial spin labeling perfusion study

To investigate the neural mechanisms underlying attention deficits that are related to neoadjuvant chemotherapy in combination with cerebral perfusion. Thirty one patients with breast cancer who were scheduled to receive neoadjuvant chemotherapy and 34 healthy control subjects were included. The patients completed two assessments of the attention network tasks (ANT), neuropsychological background tests, and the arterial spin labeling scan, which were performed before neoadjuvant chemotherapy and after completing chemotherapy. After neoadjuvant chemotherapy, the patients exhibited reduced performance in the alerting and executive control attention networks but not the orienting network (p < 0.05) and showed significant increases in cerebral blood flow (CBF) in the left posterior cingulate gyrus, left middle occipital gyrus, bilateral precentral gyrus, inferior parietal gyrus, supramarginal gyrus, angular gyrus, precuneus, cuneus, superior occipital gyrus, calcarine cortex, and temporal gyrus (p < 0.01 corrected) when compared with patients before chemotherapy and healthy controls. A significant correlation was found between the decrease performance of ANT and the increase in CBF changes in some brain regions of the patients with breast cancer. The results demonstrated that neoadjuvant chemotherapy influences hemodynamic activity in different brain areas through increasing cerebral perfusion, which reduces the attention abilities in breast cancer patients.

Motor-related brain abnormalities in HIV-infected patients: a multimodal MRI study

PurposeIt is generally believed that HIV infection could cause HIV-associated neurocognitive disorders (HAND) across a broad range of functional domains. Some of the most common findings are deficits in motor control. However, to date no neuroimaging studies have evaluated basic motor control in HIV-infected patients using a multimodal approach.MethodsIn this study, we utilized high-resolution structural imaging and task-state functional magnetic resonance imaging (fMRI) to assess brain structure and motor function in a homogeneous cohort of HIV-infected patients.ResultsWe found that HIV-infected patients had significantly reduced gray matter (GM) volume in cortical regions, which are involved in motor control, including the bilateral posterior insula cortex, premotor cortex, and supramarginal gyrus. Increased activation in bilateral posterior insula cortices was also demonstrated by patients during hand movement tasks compared with healthy controls. More importantly, the reduced GM in bilateral posterior insula cortices was spatially coincident with abnormal brain activation in HIV-infected patients. In addition, the results of partial correlation analysis indicated that GM reduction in bilateral posterior insula cortices and premotor cortices was significantly correlated with immune system deterioration.ConclusionThis study is the first to demonstrate spatially coincident GM reduction and abnormal activation during motor performance in HIV-infected patients. Although it remains unknown whether the brain deficits can be recovered, our findings may yield new insights into neurologic injury underlying motor dysfunction in HAND.