MOTOR CORTEX NETWORKS IN STROKE PATIENTS DURING RECOVERY WITH fMRI

To investigate changes of functional activation areas of the cerebral cortex and the connectivity of motor cortex networks （MCNs） in stroke patients during the recovery, five patients with the infarct in their left hemispheres are recruited. Functional magnetic resonance imaging （fMRI） is performed in the second, fourth, eighth, and sixteenth weeks after the stroke. Images are analyzed using the professional software SPM5 to obtain the bilateral activation of the motor cortex in left and right handgrip tests. MCN data are extracted from the active areas, and the structural and functional characteristic parameters are computed to indicate the connectivity of the network. Results show that the ipsilesional hemisphere recruits more areas with less active extent during the handgrip test, compared with the contralesional hemisphere. MCN shows a higher overall degree of statistical independence and more statistical dependence among motor areas with the gradual recovery. It can help physicians understand the recovery mechanism.

Functional MRI activation of primary and secondary motor areas in healthy subjects

BACKGROUND： Functional MRI （fMRI） demonstrates the localization of hand representation in the motor cortex, thereby providing feasible noninvasive mapping of functional activities in the human brain. OBJECTIVE： To observe cortical activation within different cortical motor regions during repetitive hand movements in healthy subjects through the use of fMRI. DESIGN： An observational study, with each subject acting as his own control. SETTING： Department of Radiology, the First Affiliated Hospital of Nanchang University. PARTICIPANTS： Seven healthy volunteers, 4 males and 3 females, aged 19 to 38 years, participated in the study. All subjects were right-handed, with no neurological or psychological disorders. Informed written consent was obtained from all subjects, and the study was approved by the Institutional Review Board of the First Affiliated Hospital of Nanchang University. METHODS： The study was performed at the Department of Radiology between June-August 2005. A 1.5 Tesla Siemens MRI scanner （Symphony, Germany） was used to acquire T1-weighted structural images, which were oriented parallel to the line running through the anterior and the posterior commissures. Subjects were instructed on a task and were allowed to practice briefly prior to the imaging procedure. The motor activation task consisted of the right hand performing a clenching movement. The T1-W images were acquired from six alternating epochs of rest and activation from all seven healthy subjects. Data were collected with echoplanar imaging of brain oxygen level dependent （BOLD） sequence. Each series comprised six cycles of task performance （30 seconds）, alternating with rest （30 seconds） periods, and 3-second time intervals. The differences between active and baseline fMRI imaging were calculated using the student t-test. Differential maps were overlaid on the high resolution TI-W structural image for neuroanatomical correlation of activation areas. MAIN OUTCOME MEASURES： The omega-shaped hand knobs were recognized on T1-W structural images. Active signal changes in the primary （M1） and secondary motor （M2） areas, as well as the relationship between the hand knobs and M1 area activation, were analyzed. Region of interest was selected for signal change quantitative graphic analysis. RESULTS： All 7 enrolled volunteers were included in the final analysis. In the present study, hand knob structures were recognized on T1-weighted images in all subjects and were omega-shaped in the axial plane. Significant functional activations were observed in the contralateral primary motor area of all subjects. Activation signals were distributed mainly in the central sulcus around the hand knob. The contralateral primary sensory （S1） cortex was activated in most cases, and ipsilateral M1 was activated in 3 subjects. Contralateral or bilateral supplementary motor area （SMA） was also activated in 6 cases. Premotor area, or super parietal lobe, was activated in two subjects. Three-dimensional reconstruction demonstrated that the active signal of M1 was primarily located at the middle-lateral surface of the contralateral precentral gyrus in Brodman＇s area 4, and the signal of SMA activation was located in the mesial surface of the premotor area. CONCLUSION： The knob structure of the precentral gyrus is the representative motor area for hand movement. The cerebral cortical motor network was extensively activated during voluntary hand movements in normal subjects. In alert, conscious human subjects, the activated fMRI signal safely and non-invasively localized and lateralized the motor cortical activity associated with simple voluntary repetitive hand movements. Whether higher cognitive functions, such as perception and speech, can be similarly mapped using the fMRI technique and the BOLD method remains to be determined in future well-designed human studies.

Functional connectivity and information flow in cerebral motor regions of healthy people following finger movement training

BACKGROUND：Neuro-rehabilitative training has been shown to promote motor function recovery in stroke patients,although the underlying mechanisms have not been fully clarified.OBJECTIVE：To investigate the effects of finger movement training on functional connectivity and information flow direction in cerebral motor areas of healthy people using electroencephalogram （EEG）.DESIGN,TIME AND SETTING：A self-controlled,observational study was performed at the College of Life Science and Bioengineering,Beijing University of Technology between December 2008 and April 2009.PARTICIPANTS：Nineteen healthy adults,who seldom played musical instruments or keyboards,were included in the present study.METHODS：Specific finger movement training was performed,and all subjects were asked to separately press keys with their left or right hand fingers,according to instructions.The task comprised five sessions of test train test train-test.Thirty-six channel EEG signals were recorded in different test sessions prior to and after training.Data were statistically analyzed using one-way analysis of variance.MAIN OUTCOME MEASURES：The number of effective performances,correct ratio,average response time,average movement time,correlation coefficient between pairs of EEG channels,and information flow direction in motor regions were analyzed and compared between different training sessions.RESULTS：Motor function of all subjects was significantly improved in the third test comparedwith the first test （P〈 0.01）.More than 80% of connections were strengthened in the motor-related areas following two training sessions,in particular the primary motor regions under the C4 electrode.Compared to the first test,a greater amount of information flowed from the Cz and Fcz electrodes （corresponding to supplementary motor area） to the C4 electrode in the third test.CONCLUSION：Finger task training increased motor ability in subjects by strengthening connections and changing information flow in the motor areas.These results provided a greater understanding of the mechanisms involved in motor rehabilitation.

Effects of different frequencies of repetitive transcranial magnetic stimulation on the recovery of upper limb motor dysfunction in patients with subacute cerebral infarction

Studies have confirmed that low-frequency repetitive transcranial magnetic stimulation can decrease the activity of cortical neurons, and high-frequency repetitive transcranial magnetic stimulation can increase the excitability of cortical neurons. However, there are few studies concerning the use of different frequencies of repetitive transcranial magnetic stimulation on the recovery of upper-limb motor function after cerebral infarction. We hypothesized that different frequencies of repetitive transcranial magnetic stimulation in patients with cerebral infarction would produce different effects on the recovery of upper-limb motor function. This study enrolled 127 patients with upper-limb dysfunction during the subacute phase of cerebral infarction. These patients were randomly assigned to three groups. The low-frequency group comprised 42 patients who were treated with 1 Hz repetitive transcranial magnetic stimulation on the contralateral hemisphere primary motor cortex （M1）. The high-frequency group comprised 43 patients who were treated with 10 Hz repetitive transcranial magnetic stimulation on ipsilateral M1. Finally, the sham group comprised 42 patients who were treated with 10 Hz of false stimulation on ipsilateral M1. A total of 135 seconds of stimulation was applied in the sham group and high-frequency group. At 2 weeks after treatment, cortical latency of motor-evoked potentials and central motor conduction time were significantly lower compared with before treatment. Moreover, motor function scores were significantly improved. The above indices for the low- and high-frequency groups were significantly different compared with the sham group. However, there was no significant difference between the low- and high-frequency groups. The results show that low- and high-frequency repetitive transcranial magnetic stimulation can similarly improve upper-limb motor function in patients with cerebral infarction.

Investigating connectional characteristics of Motor Cortex network

To understand the connectivity of cerebral cor-tex, especially the spatial and temporal pattern of movement, functional magnetic resonance imaging (fMRI) during subjects performing finger key presses was used to extract functional networks and then investigated their character-istics. Motor cortex networks were constructed with activation areas obtained with statistical analysis as vertexes and correlation coefficients of fMRI time series as linking strength. The equivalent non-motor cortex networks were constructed with certain distance rules. The graphic and dynamical measures of motor cor-tex networks and non-motor cortex networks were calculated, which shows the motor cortex networks are more compact, having higher sta-tistical independence and integration than the non-motor cortex networks. It indicates the motor cortex networks are more appropriate for information diffusion.

Prior Somatic Stimulation Improves Performance of Acquired Motor Skill by Facilitating Functional Connectivity in Cortico-Subcortical Motor Circuits

Once people have a well-trained motor skill, their performance becomes stabilized and achieving substantial improvement is difficult. Recently, we have shown that even a plateaued hand motor skill can be upgraded with short-period electrical stimulation to the hand prior to the task. Here, we identify the neuronal substrates underlying the improvement of the plateaued skill by examining the enhanced functional connectivity in the sensory-motor regions that are associated with motor learning. We measured brain activity using functional magnetic resonance imaging and performed psychophysiological interaction analysis. We recruited seven right-handed very-well trained participants, whose motor performance of continuously rotating two balls with their right hands became stabilized at higher performance levels. We prepared two experiments, in each of which they repeated an experimental run 16 times. In each run, they performed this cyclic rotation as many times as possible in 16 s. In the thenar-stimulation experiment, we applied 60-s stimulation to the thenar muscle before each of the 5th - 12th runs, and the others were preceded by ineffective sham stimulation. In the control experiment, the sham was always provided. Thenar stimulation enabled the participants to perform the movements at higher cycles. In association with this performance improvement, we found enhanced activity couplings between the primary motor cortex and the sensorimotor territory of the putamen and between the cerebellum and the primary sensorimotor cortices, without any quantitative activity increase. Neither behavioral change nor these increased activity couplings were observed in the control.Thus, in contrast to the stable neuronal states in the cortico-subcortical motor circuits when the well-learned task is repeated at the later stages of motor skill learning, plastic changes in the motor circuits seem to be required when the plateaued skill is upgraded, and the stimulation may entail a state of readiness for the plastic change that allows subsequent performance improvement.

Neuronal injury in the motor cortex after chronic stroke and lower limb motor impairment: a voxelbased lesion symptom mapping study

Many studies have examined motor impairments using voxel-based lesion symptom mapping, but few are reported regarding the corresponding relationship between cerebral cortex injury and lower limb motor impairment analyzed using this technique. This study correlated neuro- nal injury in the cerebral cortex of 16 patients with chronic stroke based on a voxel-based lesion symptom mapping analysis. Neuronal injury in the corona radiata, caudate nucleus and putamen of patients with chronic stroke could predict walking speed. The behavioral measure scores were consistent with motor deficits expected after damage to the cortical motor system due to stroke. These findings suggest that voxel-based lesion symptom mapping may provide a more accurate prognosis of motor recovery from chronic stroke according to neuronal injury in cerebral motor cortex.

认知功能损伤对双任务站立影响的中枢机制:功能性近红外脑成像系统分析

背景:轻度认知障碍老年人由于认知功能下降,姿势控制能力下降,易发生跌倒。双任务范式由于更贴近日常生活,常被用于评估姿势控制能力,但以往对于轻度认知障碍老年人的认知与姿势控制双任务研究主要探讨姿势控制的外在表现特征,中枢神经机制的直接证据依然缺乏。目的:探讨轻度认知障碍老年人在执行站立姿势控制-空间工作记忆双任务时大脑躯体感觉运动皮质激活特征。方法:采用蒙特利尔认知量表(MoCA-B)筛选受试者,共纳入轻度认知障碍老年人16人、认知功能正常老年人17人,进行5种任务测试,分别为空间工作记忆(SIT)、双足平衡站立(SD)、Romberg站立(SR)、双足平衡站立-空间工作记忆双任务(DD)、Romberg站立-空间工作记忆双任务(DR);同时使用功能性近红外脑成像系统和三维测力台收集躯体感觉运动皮质(20个通道)的血液动力学、足底压力中心(COP)摆动轨迹数据。结果与结论:①在Romberg站立、双足平衡站立-空间工作记忆双任务、Romberg站立-空间工作记忆双任务下,轻度认知障碍老年人前后、内外方向足底压力中心位移均显著大于认知功能正常老年人(P<0.05);②在双足平衡站立-空间工作记忆双任务下,轻度认知障碍老年人15通道(右侧前运动皮质/辅助运动区)的氧合血红蛋白变化量值显著大于认知功能正常老年人(P<0.05);在Romberg站立-空间工作记忆双任务下,轻度认知障碍老年人15,17通道(右侧前运动皮质/辅助运动区)的氧合血红蛋白变化量值均显著大于认知功能正常老年人(P<0.05);③在Romberg站立-空间工作记忆双任务下,轻度认知障碍老年人内外方向足底压力中心位移与15通道的氧合血红蛋白变化量存在显著正相关(r=0.659,P<0.05),认知功能正常老年人内外方向足底压力中心位移与15通道的氧合血红蛋白变化量存在高度正相关(r=0.840,P<0.05)。结果表明,与认知功能正常老年人相比,轻度认知障碍老年人在站立姿势控制-空间工作记忆双任务中站立姿势控制能力较弱,右侧前运动皮质与辅助运动区激活水平更高,更多的脑资源用于侧向姿势控制,可能是轻度认知障碍老年人认知衰退导致站立姿势控制能力变弱的大脑补偿机制。

Changes in brain activation in stroke patients after mental practice and physical exercise: a functional MRI study

Mental practice is a new rehabilitation method that reters to the mental rehearsal ot motor imagery content with the goal of improving motor performance. However, the relationship between activated regions and motor recovery after mental practice training is not well understood. In this study, 15 patients who suffered a firstever subcortical stroke with neurological deficits affecting the right hand, but no significant cognitive impairment were recruited. 10 patients underwent mental practice combined with physical practice training, and 5 patients only underwent physical practice training. We observed brain activation regions after 4 weeks of training, and explored the correlation of activation changes with functional recovery of the affected hands. The results showed that, after 4 weeks of mental practice combined with physical training, the Fugl-Meyer assessment score for the affected right hand was significantly increased than that after 4 weeks of practice training alone. Functional MRI showed enhanced activation in the left primary somatosensory cortex, attenuated activation intensity in the right primary motor cortex, and enhanced right cerebellar activation observed during the motor imagery task using the affected right hand after mental practice training. The changes in brain cortical activity were related to functional recovery of the hand. Experimental findings indicate that cortical and cerebellar functional reorganization following mental practice contributed to the improvement of hand function.

不同治疗时程的重复经颅磁刺激对脑卒中患者上肢运动功能及脑功能连接的影响

目的:以非受累侧前运动皮质区(premotor cortex,PMC)为刺激靶点,比较不同治疗时程的重复经颅磁刺激(repeated transcranial magnetic stimulation,rTMS)对脑卒中患者上肢运动功能及脑功能连接的影响。方法:将60例缺血性脑卒中后上肢运动功能障碍患者随机分到6周rTMS组、4周rTMS组和2周r TMS组以及对照组,每组15例。在治疗前后采用上肢Brunnstrom分期、Fugl-Meyer运动功能评分上肢部分(Fugl-Meyer assessment of upper extremity,FMA-UE)和Wolf运动功能评分(Wolf motor function test,WMFT)进行行为学评定,另外以非受累侧PMC为种子点采用静息态功能磁共振成像(resting state functional magnetic resonance imaging,rs-fMRI)进行功能连接分析。结果:治疗后,2周rTMS组的FMA-UE和WMFT的评分与4周及6周rTMS组间有显著性差异(P<0.05),但4周rTMS组的FMA-UE和WMFT的评分与6周rTMS组间无显著性差异(P>0.05)。非受累侧PMC区为种子点的功能连接分析显示,rTMS治疗后非受累侧PMC与同侧中央前回、对侧颞中回和楔前叶功能连接增强(P<0.05)。结论:研究结果表明,以非受累侧半球PMC为靶点的低频rTMS治疗可有效促进偏瘫上肢运动功能的恢复,其中与2周rTMS干预和6周rTMS干预相比,4周rTMS干预具有最佳的时间-效益比,这可能与其增强双侧半球间、非受累半球内皮质-皮质间的功能连接有关。

孤独症儿童的“体育与健康课程”教学内容设计与教学效果检验

目的:设计符合孤独症(孤独症谱系障碍,Autism Spectrum Disorders, ASD)儿童身心发展的“体育与健康课程”教学内容,通过10周教学实验检验其对ASD儿童动作协调能力和运动皮质静息功能连接的影响。方法:根据孤独症儿童的身心发展特点,设计了一套以执行功能提升和篮球技术提高为目的的教学内容。共招募11名ASD儿童,持续进行为期10周的教学实验。实验前、后分别应用动作协调能力测量量表(M-ABC2)量表测量受试者动作协调能力,运用功能近红外光谱(fNIRS)监测运动皮质安静状态下的血氧信号,并用“FC-NIRS”软件计算脑区的静息功能连接(RSFC)强度。结果:(1)在实验前后,ASD儿童M-ABC2总分及一级指标(手部精细动作、手眼协调动作以及动态静态平衡能力)均未见有显著性变化(P>0.05);(2)在HbO水平上,实验前后运动皮质RSFC具有临界显著变化(t=2.30,P=0.06),且具有较大的效应量(d=0.87)。结论:持续10周的执行功能和篮球运动对ASD儿童动作协调能力的影响不显著,但对运动皮质静息功能连接具有一定的作用。

经颅直流电刺激不同靶点治疗帕金森病效果的网状Meta分析

目的:系统评价经颅直流电刺激对帕金森患者运动功能的康复疗效,并比较经颅直流电刺激作用于不同靶点对帕金森患者运动功能的疗效差异,为临床中经颅直流电刺激的靶点选择提供理论依据。方法:计算机检索Cochrane Library、PubMed、Web of Science、中国知网、维普和万方数据库,以“帕金森、经颅直流电刺激”为中文检索词,以“Parkinson,transcranial direct current stimulation”为英文检索词,收集从各数据库建库至2023年1月发表的关于经颅直流电刺激改善帕金森患者运动功能的随机对照试验。使用Cochrane 5.1.0偏倚风险评估工具和PEDro量表对纳入研究进行质量评价。采用RevMan 5.4和Stata 17.0软件对结局指标进行Meta分析。结果:①最终纳入15项随机对照试验,PEDro量表评估显示均为高质量或极高质量研究。②Meta分析显示,与对照组相比经颅直流电刺激可显著提高UPDRS-Ⅲ评分(MD=-2.49,95%CI:-4.42至-0.55,P<0.05)、步频评分(MD=0.07,95%CI:0.03-0.11,P<0.05)和步速评分(MD=0.02,95%CI:0.00-0.05,P<0.05),但对BBS评分(MD=2.57,95%CI:-0.74-5.87,P>0.05)的提高不明显。③网状Meta分析概率排序结果显示,在UPDRS-Ⅲ评分方面,刺激靶点疗效的概率排序结果为背外侧前额叶皮质(52.4%)>初级皮质运动区(45.8%)>大脑中央点(1.8%)>常规康复治疗(0%);在步频评分方面,刺激靶点疗效的概率排序结果为小脑(50.1%)>大脑中央点(45.8%)>背外侧前额叶皮质(3.9%)>初级皮质运动区(0.2%)>常规康复治疗(0%);在步速评分方面,刺激靶点疗效的概率排序结果为小脑(64.8%)>背外侧前额叶皮质(23.8%)>大脑中央点(9.4%)>初级皮质运动区(1.7%)>常规康复治疗(0.4%);在BBS评分方面,刺激靶点疗效的概率排序结果为:小脑(77.4%)>背外侧前额叶皮质(20.7%)>大脑中央点(0.7%)>常规康复治疗(0.2%)。结论:经颅直流电刺激可显著改善帕金森患者运动功能,其中刺激背外侧前额叶皮质区域对改善帕金森患者运动协调方面疗效更佳,而刺激小脑区域对改善帕金森患者步行和平衡方面疗效更佳。

Changes in brain activation patterns according to cross-training effect in serial reaction time task An functional MRI study

Cross-training is a phenomenon related to motor learning, where motor performance of the untrained limb shows improvement in strength and skill execution following unilateral training of the homologous contralateral limb. We used functional MRI to investigate whether motor performance of the untrained limb could be improved using a serial reaction time task according to motor sequential learning of the trained limb, and whether these skill acquisitions led to changes in brain activation patterns. We recruited 20 right-handed healthy subjects, who were randomly allocated into training and control groups. The training group was trained in performance of a serial reaction time task using their non-dominant left hand, 40 minutes per day, for 10 days, over a period of 2 weeks. The control group did not receive training. Measurements of response time and percentile of response accuracy were performed twice during pre- and post-training, while brain functional MRI was scanned during performance of the serial reaction time task using the untrained right hand. In the training group, prominent changes in response time and percentile of response accuracy were observed in both the untrained right hand and the trained left hand between pre- and post-training. The control group showed no significant changes in the untrained hand between pre- and post-training. In the training group, the activated volume of the cortical areas related to motor function （i.e., primary motor cortex, premotor area, posterior parietal cortex） showed a gradual decrease, and enhanced cerebellar activation of the vermis and the newly activated ipsilateral dentate nucleus were observed during performance of the serial reaction time task using the untrained right hand, accompanied by the cross-motor learning effect. However, no significant changes were observed in the control group. Our findings indicate that motor skills learned over the 2-week training using the trained limb were transferred to the opposite homologous limb, and motor skill acquisition of the untrained limb led to changes in brain activation patterns in the cerebral cortex and cerebellum.

舌面散刺联合经颅磁刺激技术对脑卒中后吞咽困难患者咽运动皮质、神经功能及血清GDF-15、S100β蛋白的影响

目的探究舌面散刺联合经颅磁刺激技术(TMS)对脑卒中后吞咽困难患者咽运动皮质、神经功能及血清生长分化因子15(GDF-15)、可溶性蛋白-100β(S100β)的影响。方法前瞻性选取2021年5月至2023年2月海南医学院第二附属医院康复科收治的脑卒中后吞咽困难患者104例为研究对象,按照随机数表法将其分为观察组(n=50)和对照组(n=54)。所有患者进行常规治疗,对照组同时行TMS治疗,每次20 min,每天1次,每周3次,持续治疗4周;观察组在对照组的基础上联合舌面散刺治疗,每天1次,每周6次,持续治疗4周。比较两组治疗前、治疗4周后的中医证候评分、吞咽障碍造影评分量表(VDS)评分和渗透-误吸量表(PAS)评分、美国国立卫生研究院卒中量表(NIHSS)评分、洼田饮水试验量表评分。检测并比较两组患者治疗前、治疗4周后的血清GDF-15、S100β表达水平变化以及治疗期间不良反应发生情况。结果治疗4周后,观察组的舌卷痿缩、进食缓慢、饮水发呛、舌质瘀斑/黯淡以及脉细涩证候的评分分别为(1.90±0.01)、(2.69±0.75)、(2.66±0.24)、(1.02±0.13)、(1.18±0.20)分,均低于对照组[(2.54±0.34)、(3.05±0.24)、(3.85±0.71)、(1.17±0.22)、(1.32±0.09)分],差异均有统计学意义(P<0.05)。治疗4周后,两组VDS、PAS评分均较治疗前下降,且观察组VDS、PAS评分分别为(25.01±5.74)、(1.65±0.04)分,均低于对照组[(28.01±6.82)、(2.00±0.18)分],差异均有统计学意义(P<0.05)。治疗4周后,两组NIHSS评分及洼田饮水试验评分均较治疗前下降,且观察组NIHSS、洼田饮水试验评分分别为(9.86±1.50)、(1.54±0.33)分,均低于对照组[(13.24±0.92)、(1.97±0.76)分],差异均有统计学意义(P<0.05)。治疗4周后,两组GDF-15水平较治疗前降低,S100β水平较治疗前升高,观察组GDF-15为(443.05±13.00)pg/mL,低于对照组[(487.24±26.51)pg/mL],S100β水平为(0.21±0.03)μg/L,高于对照组[(0.18±0.04)μg/L],差异均有统计学意义(P<0.05)。观察组与对照组患者不良反应总共发生率比较(6.00%vs.3.70%),差异无统计学意义(P>0.05)。结论舌面散刺联合TMS治疗方案可有效改善脑卒中后吞咽困难患者的临床证候,刺激其咽运动皮质以促进其吞咽功能的修复,同时还可有效改善其神经功能及血清GDF-15、S100β蛋白表达。

利用fMRI和双手交替运动模式研究脑肿瘤所致的运动功能重组

目的应用fMRI研究双手交替运动模式下中央沟附近脑肿瘤患者运动功能重组的方式及特征。方法6名正常受试者和14名脑肿瘤患者采用双手交替对指运动模式行fMRI扫描,比较正常受试者与脑肿瘤患者脑激活的异同。结果正常人单手对指运动主要激活运动手对侧的大脑半球和同侧小脑半球。脑肿瘤患者非受累手运动所致的激活与正常受试者基本相同;而当受累手运动时,则出现运动功能的重组,包括肿瘤对侧正常半球内M1区的代偿性激活、肿瘤侧半球MI活动的减弱、双侧SMA等次级运动中枢激活区的增大以及双侧小脑半球的激活。结论采取双手交替运动模式,fMRI不仅显示了受累侧运动区的变形与移位,而且揭示了一种新的功能重组模式,即运动功能重组可能涉及分布于全脑的整个神经网络。

利用功能磁共振成像对皮质下脑梗死运动功能恢复机制的研究

目的利用功能磁共振成像(fMRI)对皮质下脑梗死运动功能恢复的神经机制进行探讨。方法选择运动功能恢复较好的慢性期单侧皮质下脑梗死患者23例为患者组,年龄匹配的健康志愿者24例为对照组。用FuglMeyer量表评价患者的运动功能。fMRI实验采用组块设计,分别进行双手虚握拳运动,采用统计参数图比较2组执行手运动任务时脑激活的异同。结果对照组及患者组健手运动主要激活运动对侧感觉运动区、同侧小脑半球及双侧辅助运动区。患者组患手运动激活部位与对照组相同。与对照组比较,患者组患手运动时病灶侧初级运动皮质(M1)激活增强。结论在运动通路皮质下脑梗死患者运动功能恢复中,病灶侧M1区激活增强起重要作用。

受病变累及的运动中枢fMR表现

目的 观察正常及受病变累及的运动中枢的脑功能核磁共振成像（ｆＭＲ）表现。方法 通过双手对指运动使运动中枢功能活跃，然后对１４例正常志愿者和３６例运动中枢受累的病人进行运动功能区血氧水平依赖法（ＢＯＬＤ）ｆＭＲ成像。结果 通过双手对指运动使运动中枢功能活跃，正常志愿者和病人脑内产生了相应的功能信号，表现为功能区信号增高。在正常志愿者中，双侧半球运动功能区的位置基本对称，但大部分志愿者左侧半球功能信号稍强于对侧半球。在累及运动中枢病变的病人中，病变侧功能信号全部位于病变外或病变边缘，病变内未见功能信号。病侧功能区主要表现为功能信号降低、移位。结论ＢＯＬＤ法ｆＭＲ可以很好的显示正常和病变的运动中枢，是评价运动中枢的有效方法。

磁刺激在生物医学中的应用

磁刺激技术由于具有有效性和无创性,近来在临床上得到了广泛的应用。磁刺激主要应用于中枢运动通路传导测量和运动皮质兴奋性评价;检测外周神经传导速度,监测中枢神经系统机能状态;研究大脑皮层神经分布,为人类实现对某些脑生理活动的人为调控,探索脑疾病的诊断、治疗方法提供新的手段。本文就磁刺激的物理原理和作用机理,以及磁刺激在生物医学检测及治疗方面作了综述。

功能性近红外光谱技术在利手、非利手主动抓握-释放任务下脑区激活研究中的应用

目的探讨功能性近红外光谱技术(fNIRS)观察健康人利手、非利手复杂运动模式下双侧感觉运动区(SMC)、运动前区(PMC)激活模式中的应用价值。方法2019年8月至12月,社区招募右利手健康人15例,采用Block设计,执行抓握-释放握力器任务,于双侧SMC、PMC和前额叶皮质行fNIRS探测,根据氧合血红蛋白和脱氧血红蛋白浓度变化观察两种运动状态下脑区激活通道及强度。结果根据氧合血红蛋白浓度,右(利)手运动时,双侧激活通道数相同,左侧SMC激活平均β值更高(P<0.05);左(非利)手运动时,对侧激活通道更多,右侧SMC激活平均β值更高(P<0.05)。根据脱氧血红蛋白浓度,利手或非利手运动时,对侧激活通道更多;右(利)手运动时,左侧SMC激活平均β值更高(P<0.05),通道12(左侧PMC)和通道26(右侧PMC)激活更强(P<0.05)。结论fNIRS可用于利手、非利手复杂运动模式下手运动相关脑区激活的研究,应更关注氧合血红蛋白浓度变化的结果。

基于fNIRS的运动执行与运动想象脑激活模式比较

使用《运动想象问卷-修订版》筛选出的30名被试(男女各半),采用功能性近红外光谱成像技术(fNIRS)监测被试在执行实际举哑铃(男生,4磅和8磅;女生,2磅和4磅)任务和想象举同等重量哑铃任务时,其大脑皮层氧合血红蛋白浓度的变化。结果发现:男女被试在运动执行与运动想象任务下都激活了主运动皮层;且运动执行的大脑激活水平高于运动想象。在执行实际运动任务时,运动强度显著影响大脑皮层血氧浓度的变化,表现出左半球偏侧化优势;在执行想象运动任务时,运动强度没有影响大脑皮层血氧浓度的变化,且无偏侧化现象。