Objective To assess any differences in brain activation during active,passive and imaginary movement of the hands using blood oxygen level-dependent functional magnetic resonance imaging (fMRI),and to provide references for the cortical reorganization in patients with brain injuries.Methods Twenty healthy,righthanded,adult volunteers were studied,fMRI was performed during active,passive and imaginary fist clutching.Whole brain analysis and group analysis were applied to get the voxels,the volume of activation,the peak t-score and its coordinates.Results Active and passive movement both produced significant activation in the contralateral sensorimotor cortex,the contralateral supplementary motor area and the ipsilateral cerebellum.The sensorimotor cortex was the most frequently and most strongly activated brain area.Imaginary movement produced significant bilateral activation in the supplementary motor area.Conclusions Active and passive movement induce similar brain activation patterns.This indicates that passive might replace active movement when observing activation of the brain's cortex during the rehabilitation of patients with hemiplegia.

Background We aimed to investigate the disruptions of functional connectivity of amygdala-based networks in adolescents with untreated generalized anxiety disorder (GAD). Material/Methods A total of 26 adolescents with first-episode GAD and 20 normal age-matched volunteers underwent resting-state and T1 functional magnetic resonance imaging (fMRI). We analyzed the correlation of fMRI signal fluctuation between the amygdala and other brain regions. The variation of amygdala-based functional connectivity and its correlation with anxiety severity were investigated. Results Decreased functional connectivity was found between the left amygdala and left dorsolateral prefrontal cortex. An increased right amygdala functional connectivity with right posterior and anterior lobes of the cerebellum, insula, superior temporal gyrus, putamen, and right amygdala were found in our study. Negative correlations between GAD scores and functional connectivity of the right amygdala with the cerebellum were also observed in the GAD adolescents. Conclusions Adolescents with GAD have abnormalities in brain regions associated with the emotional processing pathways.

目的:利用功能磁共振(fMRI)研究脑卒中患者运动想象训练后上肢功能重组潜在的脑重塑机制,为临床脑卒中患者的康复治疗提供一定的理论基础.方法:选择9例脑卒中偏瘫患者,进行运动想象训练每周5次,每次约30min,共4周,并进行常规康复训练.应用Fugl-Meyer上肢运动功能量表(FMA-UL)分别在治疗前和治疗后4周评估患者的上肢运动功能.在4周康复干预前后对患者进行患手被动握拳任务下的fMRI检查,采用组块设计,利用SPM8软件进行数据处理,采用感兴趣区(ROI)的个体化分析,统计各ROI区的脑皮质激活情况,比较干预前后对侧感觉运动区(cSMC)的激活变化,分析脑卒中患者的脑重塑模式.结果:4周运动想象干预后脑卒中患者的FM-UL评分从(22.44±11.59)分提高到(39.78±14.03)分(P=0.0 11).比较干预前后两次fMRI检查脑皮质SMC区的激活情况,发现9例脑卒中患者的功能恢复呈现出两种不同的皮质重塑模式:一种模式为募集激活,即大部分患者第二次fMRI检查,患手被动任务下cSMC的激活增加(有6例患者);另一种模式是集中激活,即小部分患者第二次fMRI检查,患手被动任务下cSMC的激活虽然是减少的,但其偏侧指数(LI-SMC)却是显著增加的(有3例患者).结论:运动想象训练可改善脑卒中患者的上肢运动功能,经过4周干预后脑卒中患者存在损伤同侧SMC区的募集激活和集中激活两种脑重塑模式,随着患者上肢功能的恢复,脑重塑机制逐渐倾向于损伤侧SMC的激活.

Cerebral neuroplasticity after stroke has been elucidated by functional neuroimaging. However, little is known concerning how topological properties of the cortical motor-related network evolved following subcortical stroke. In the present study, we investigated 24 subcortical stroke patients with only left motor pathway damaged and 24 matched healthy controls. A cortical motor-related network consisting of 20 brain regions remote from the primary lesion was constructed using resting-state functional MRI datasets. We subsequently used graph theoretical approaches to analyze the topological properties of this network in both stroke patients and healthy controls. In addition, we divided the stroke patients into two subgroups according to their outcomes in hand function to explore relationships between topological properties of this network and outcomes in hand function. Although we observed that the cortical motor-related network in both healthy controls and stroke patients exhibited small-world topology, the local efficiency of this network in stroke patients is higher than and global efficiency is lower than those in healthy controls. In addition, striking alterations in the betweenness centrality of regions were found in stroke patients, including the contralesional supplementary motor area, dorsolateral premotor cortex, and anterior inferior cerebellum. Moreover, we observed significant correlations between betweenness centrality of regions and Fugl-Meyer assessment scores. A tendency for the cortical motor-related network to be close to a regular configuration and altered betweenness centrality of regions were demonstrated in patients with subcortical stroke. This study provided insight into functional organization after subcortical stroke from the viewpoint of network topology.

Sir, Albert Einstein was arguably the greatest physicist in the 20th century and his extraordinary intelligence has long intrigued both scientists and the general public. Despite several studies that focused mainly on the histological and morphological features of Einstein’s brain after his death, the substrates of Einstein’s genius are still a mystery (Diamond et al. , 1985; Anderson and Harvey, 1996; Kigar et al. , 1997; Hines, 1998; Witelson et al. , 1999 a , b ; Colombo et al. , 2006; Falk, 2009). Recently, Falk et al. (2013) analysed 14 newly discovered photographs and found that Einstein’s brain had an extraordinary prefrontal cortex, and that inferior portions of the primary somatosensory and motor cortices were greatly expanded in the left hemisphere. Among these 14 images were photographs of the left and right medial surface of Einstein’s brain, on which the corpus callosum was shown with great resolution and accuracy. The corpus callosum is the largest nerve fibre bundle that connects the cortical regions of the cerebral hemispheres in human brains and it plays an essential role in the integration of information transferred between the hemispheres over thousands of axons (Aboitiz et al. , 1992). The two photographs of the medial surfaces of Einstein’s cerebral hemispheres provide the basis for the present study. To examine whether there are regional callosal differences between the brain of Einstein and those of ordinary people, and to minimize potential differences in corpus callosum morphology due to cause of death, brain atrophy, age, and sex, in vivo MRI data sets from two different age groups were used. The high-resolution photographs of Einstein’s left and right hemispheres were supplied by Dean Falk with permission from the National Museum of Health and Medicine (Fig. 1). Because Einstein was right-handed and died at …

Despite its clinical efficacy, few studies have examined the neural mechanisms of motor imagery training (MIT) in stroke. Our objective was to find the cortical reorganization patterns after MIT in chronic stroke patients.