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1.
This clinical trial investigated the effect of an Emotional Freedom Techniques (EFT) intervention on brain activation in chronic pain sufferers using functional magnetic resonance imaging (fMRI). EFT is a brief stress reduction technique which combines stating a cognitive statement with somatic tapping on acupressure points. Twenty-four adults were allocated to a six-week online group EFT treatment and underwent resting-state fMRI pre and post the intervention. A repeated measures MANOVA indicated significant differences in the levels of pain severity (−21%), pain interference (−26%), quality of life (+7%), somatic symptoms (−28%), depression (−13.5%), anxiety (−37.1%), happiness (+17%), and satisfaction with life (+8.8%) from pre-to post-test. Cohen's effect sizes ranged from small (0.2) to large (0.75) values suggesting significance for the intervention. fMRI analysis showed post-EFT treatment significantly decreased connectivity between the medial prefrontal cortex (a pain modulating area) and bilateral grey matter areas in the posterior cingulate cortex and thalamus, both areas being related to modulating and catastrophizing of pain. There were no brain areas that showed significantly increased connectivity post-EFT treatment. Coupled with the psychological measures the findings support the effects of the EFT intervention in reducing chronic pain and its impacts. Recommendations for future research are discussed.  相似文献   
2.
《Brain stimulation》2019,12(6):1526-1536
BackgroundEvidence suggests that repetitive transcranial magnetic stimulation (rTMS), a non-invasive neuromodulation technique, alters resting brain activity. Despite anecdotal evidence that rTMS effects wear off, there are no reports of longitudinal studies, even in humans, mapping the therapeutic duration of rTMS effects.ObjectiveHere, we investigated the longitudinal effects of repeated low-intensity rTMS (LI-rTMS) on healthy rodent resting-state networks (RSNs) using resting-state functional MRI (rs-fMRI) and on sensorimotor cortical neurometabolite levels using proton magnetic resonance spectroscopy (MRS).MethodsSprague-Dawley rats received 10 min LI-rTMS daily for 15 days (10 Hz or 1 Hz stimulation, n = 9 per group). MRI data were acquired at baseline, after seven days and after 14 days of daily stimulation and at two more timepoints up to three weeks post-cessation of daily stimulation.Results10 Hz stimulation increased RSN connectivity and GABA, glutamine, and glutamate levels. 1 Hz stimulation had opposite but subtler effects, resulting in decreased RSN connectivity and glutamine levels. The induced changes decreased to baseline levels within seven days following stimulation cessation in the 10 Hz group but were sustained for at least 14 days in the 1 Hz group.ConclusionOverall, our study provides evidence of long-term frequency-specific effects of LI-rTMS. Additionally, the transient connectivity changes following 10 Hz stimulation suggest that current treatment protocols involving this frequency may require ongoing “top-up” stimulation sessions to maintain therapeutic effects.  相似文献   
3.
采用静息态fMRI并基于局部一致性(regional homogeneity,ReHo)和独立成分分析(independent component analysis,ICA)方法研究卒中后抑郁患者(post-stroke depression,PSD)局部自发脑活动和默 认网络(default mode network,DMN)功能连接变化模式。 方法 纳入自2017年1月-2019年1月期间新乡医学院第一附属医院收治的20例PSD患者(PSD组),以 及年龄、性别和受教育程度等均匹配的单纯缺血性卒中未抑郁患者19例(对照组)。分别采用MMSE、 汉密尔顿抑郁量表17项(Hamilton depression scale-17,HAMD-17)测试受试者的认知功能和抑郁情绪; 然后采集静息态fMRI数据,图像预处理后计算ReHo值并提取两组DMN成分。比较组间ReHo值和DMN功 能连接差异,并提取差异脑区的ReHo值和功能连接值与PSD组患者HAMD-17评分进行相关性分析。 结果 与对照组相比,PSD组右侧海马旁回和左侧小脑脚2区ReHo值升高(P <0.001,体素值>20 mm3, 未校正),并且在DMN中左侧楔前叶功能连接增强[P =0.011,校正错误发现率(false discovery rate, FDR)]、右侧楔叶功能连接减弱(P =0.006,校正FDR)。右侧海马旁回的ReHo值与HAMD-17评分呈正 相关(r =0.556,P =0.011);右侧楔叶功能连接值与HAMD-17评分呈负相关(r =-0.574,P =0.008)。 结论 PSD患者存在局部自发脑活动以及DMN功能连接异常并与患者的抑郁情绪相关。  相似文献   
4.
Variability of neural signaling is an important index of healthy brain functioning, as is signal complexity, which relates to information processing capacity. Alterations in variability and complexity may underlie certain brain dysfunctions. Here, resting-state fMRI was used to examine variability and complexity in children and adolescents with and without autism spectrum disorder (ASD). Variability was measured using the mean square successive difference (MSSD) of the time series, and complexity was assessed using sample entropy. A categorical approach was implemented to determine if the brain measures differed between diagnostic groups (ASD and controls). A dimensional approach was used to examine the continuum of relationships between each brain measure and behavioral severity, age, IQ, and the global efficiency (GE) of each participant’s structural connectome, which reflects the structural capacity for information processing. Using the categorical approach, no significant group differences were found for neither MSSD nor entropy. The dimensional approach revealed significant positive correlations between each brain measure, GE, and age. Negative correlations were observed between each brain measure and the severity of ASD behaviors across all participants. These results reveal the nature of variability and complexity of BOLD signals in children and adolescents with and without ASD.  相似文献   
5.
《Brain stimulation》2022,15(5):1269-1278
BackgroundDeep brain stimulation of the internal globus pallidus (GPi DBS) is an invasive therapeutic modality intended to retune abnormal central nervous system patterns and relieve the patient of dystonic or other motor symptoms.ObjectivesThe aim of the presented research was to determine the neuroanatomical signature of GPi DBS modulation and its association with the clinical outcome.MethodsThis open-label fixed-order study with cross-sectional validation against healthy controls analysed the resting-state functional MRI activity changes induced by GPi DBS in 18 dystonia patients of heterogeneous aetiology, focusing on both global (full brain) and local connectivity (local signal homogeneity).ResultsCompared to the switched-off state, the activation of GPi DBS led to the restoration of global subcortical connectivity patterns (in both putamina, diencephalon and brainstem) towards those of healthy controls, with positive direct correlation over large-scale cortico-basal ganglia-thalamo-cortical and cerebellar networks with the clinical improvement. Nonetheless, on average, GPi DBS also seemed to bring local connectivity both in the cortical and subcortical regions farther away from the state detected in healthy controls. Interestingly, its correlation with clinical outcome showed that in better DBS responders, local connectivity defied this effect and approached healthy controls.ConclusionsAll in all, the extent of restoration of both these main metrics of interest towards the levels found in healthy controls clearly correlated with the clinical improvement, indicating that the restoration of network state towards more physiological condition may be a precondition for successful GPi DBS outcome in dystonia.  相似文献   
6.
Resting-state fMRI studies investigating the pathophysiology of depression have identified prominent abnormalities in large-scale brain networks. However, it is unclear if localized dysfunction of specialized brain regions contribute to network-level abnormalities. We employed a meta-analytical procedure and reviewed studies conducted in China investigating changes in regional homogeneity (ReHo), a measure of localized intraregional connectivity, from resting-state fMRI in depression. Exploiting the statistical power gained from pooled analysis, we also investigated the effects of age, gender, illness duration and treatment on ReHo. The medial prefrontal cortex (MPFC) showed the most robust and reliable increase in ReHo in depression, with greater abnormality in medication-free patients with multiple episodes. Brain networks that relate to this region have been identified previously to show aberrant connectivity in depression, and we propose that the localized neuronal inefficiency of MPFC exists alongside wider network level disruptions involving this region.  相似文献   
7.
目的 采用脑静息态功能磁共振成像(rs-fMRI)局部一致性(ReHo)方法探讨重度抑郁症(MDD)患者脑区自发性活动特征,评价其与抑郁严重程度的相关性.方法 对24例MDD患者和26例相匹配的康对照组(HC)进行rs-fMRI扫描,分析两组ReHo值,将差异显著的脑区内平均ReHo值与HAMD-17评分进行相关性分析.结果 MDD患者较HC组左侧直回、左侧海马、右侧楔前叶、右侧顶上回、左侧顶下缘角回、右侧楔叶ReHo值显著升高;右背外侧前额叶、右侧后扣带回、左侧枕下回、双侧颞下回、右侧颞上回ReHo值降低(P<0.05,Alphasim矫正).Pearson相关分析显示两组差异脑区左侧海马ReHo值与HAMD-17评分呈正相关(r=0.593,P=0.002),右侧后扣带回ReHo值与HAMD-17评分呈负相关(r=-0.431,P=0.035).结论 MDD患者静息态下脑功能损害主要集中于边缘系统及默认网络等多个脑区,且左侧海马与右侧后扣带回局部脑区自发活动的时间同步性与抑郁严重程度存在相关性.ReHo分析可作为抑郁症严重程度评价的潜在生物学标记.  相似文献   
8.
The ultrafast spatiotemporal dynamics of large-scale neural networks can be examined using resting-state electroencephalography (EEG) microstates, representing transient periods of synchronized neural activity that evolve dynamically over time. In adults, four canonical microstates have been shown to explain most topographic variance in resting-state EEG. Their temporal structures are age-, sex- and state-dependent, and are susceptible to pathological brain states. However, no studies have assessed the spatial and temporal properties of EEG microstates exclusively during early childhood, a critical period of rapid brain development. Here we sought to investigate EEG microstates recorded with high-density EEG in a large sample of 103, 4–8-year-old children. Using data-driven k-means cluster analysis, we show that the four canonical microstates reported in adult populations already exist in early childhood. Using multiple linear regressions, we demonstrate that the temporal dynamics of two microstates are associated with age and sex. Source localization suggests that attention- and cognitive control-related networks govern the topographies of the age- and sex-dependent microstates. These novel findings provide unique insights into functional brain development in children captured with EEG microstates.  相似文献   
9.
AimsNear-infrared spectroscopy (NIRS) is a non-invasive, easy to apply, optical technology for measuring cerebral blood oxygenation, but there is lack of comprehensive population data to aid interpretation and clinical use. Given the importance of cerebral perfusion in the context of evolving guideline recommendations for more aggressive lowering of blood pressure (BP) in hypertension, even in the oldest old, understanding of normative NIRS values is timely. We estimated normative values of cerebral oxygenation measured by NIRS in a large community-dwelling population sample of adults aged > = 50 years (n = 3110). We hypothesized that measurements would be attenuated by cardiovascular risk factors.MethodsData from Wave 3 of The Irish Longitudinal Study on Ageing (TILDA) was utilized. Frontal lobe cerebral oxygenation was continuously measured via a Portalite, while participants rested in the supine position. Beat-to-beat BP was measured simultaneously. Normative data was modelled using generalized additive models for location, scale, and shape (GAMLSS). Multivariate linear regressions were used to examine associations with cardiovascular risk factors.ResultsAll three measures of NIRS (TSI, O2Hb and HHb) declined with increasing age. O2Hb and HHb were significantly lower in males than females. Increased smoking, excess alcohol intake, a higher waist-hip ratio, diabetes, angina, congestive heart failure, transient ischemic attack and total cardiovascular disease burden were all associated with decreased cerebral oxygenation.ConclusionWe present for the first time, normative resting-state NIRS reference data from a large population, which contributes to clinical interpretation of NIRS and advances the use of NIRS as a standard clinical tool.  相似文献   
10.
Sex differences in reading performance have been considered a relatively stable phenomenon. However, there is no general agreement about their neural basis, which might be due to that sex differences are largely influenced by age. This paper focuses on the sex differences in the reading-related neural network of Chinese children and its interaction with age. We also attempt to predict reading abilities based on neural network. Fifty-three boys and 56 girls (8.2–14.6 years of age) were recruited. We collected their resting-state fMRI and behavioural data. Restricted sex differences were found in the resting-state reading neural network compared to extensive age by sex interaction effect. Specifically, the interactions between sex and age indicated that with increasing age, girls showed greater connectivity strength between visual orthographic areas and other brain areas within the reading network, while boys showed an opposite trend. After controlling age, the prediction models of reading performance for the girls mainly included interhemispheric connections, while the intrahemispheric connections (particularly the phonological route) mainly contributed to predicting the reading ability for boys. Taken together, these findings suggest that sex differences in reading neural networks are modulated by age. Partialling out age, boys and girls also show the stable sex differences in relationship between reading neural circuit and reading behaviour.  相似文献   
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