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OBJECTIVE:To systematically evaluate the efficacy of transcranial direct current stimulation on the motor function of patients with Parkinson's disease,and to compare the efficacy of transcranial direct current stimulation at different targets on the motor function of patients with Parkinson's disease,so as to provide a theoretical basis for the target selection of transcranial direct current stimulation in clinical practice. METHODS:Cochrane Library,PubMed,Web of Science,CNKI,VIP,WanFang Data were retrieved for randomized controlled trials on the improvement of motor function in patients with Parkinson's disease by transcranial direct current stimulation published from the database inception to January 2023.The keywords were"Parkinson,transcranial direct current stimulation"in English and Chinese.The quality of the included studies was evaluated using the Cochrane 5.1.0 risk of bias assessment tool and the PEDro scale.Meta-analysis of outcome indicators was performed using RevMan 5.4 and Stata 17.0 software. RESULTS:Fifteen randomized controlled trials were finally included,and the PEDro scale showed that all were high-quality or very high-quality studies.Meta-analysis showed that transcranial direct current stimulation significantly improved Unified-Parkinson Disease Rating Scale part III score[mean difference(MD)=-2.49,95%confidence interval(CI):-4.42 to-0.55,P<0.05),step frequency score(MD=0.07,95%CI:0.03-0.11,P<0.05)and step speed score(MD=0.02,95%CI:0.00-0.05,P<0.05),but not for Berg Balance Scale scores(MD=2.57,95%CI:-0.74 to 5.87,P>0.05).Network Meta-analysis probability ranking:In terms of Unified-Parkinson Disease Rating Scale part III scores,the probability ranking results of target stimulation efficacy were dorsal lateral prefrontal cortex(52.4%)>primary motor cortex(45.8%)>central point of the brain(1.8%)>conventional rehabilitation(0%);in terms of gait frequency scores,the probability probability ranking results of target stimulation efficacy were cerebellum(50.1%)>central point of the brain(45.8%)>dorsal lateral prefrontal cortex(3.9%)>primary motor cortex(0.2%)>conventional rehabilitation(0%);in terms of gait speed scores,the probability ranking results of target stimulation efficacy were cerebellum(64.8%)>dorsal lateral prefrontal cortex(23.8%)>central point of the brain(9.4%)>primary motor cortex(1.7%)>conventional rehabilitation(0.4%);in terms of Berg Balance Scale scores,the probability ranking results of target stimulation efficacy were cerebellum(77.4%)>dorsal lateral prefrontal cortex(20.7%)>central point of the brain(0.7%)>conventional rehabilitation(0.2%). CONCLUSION:Transcranial direct current stimulation significantly improves motor function of patients with Parkinson's disease,with better motor coordination in the dorsolateral prefrontal cortex and better walking and balance in the cerebellum.
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BACKGROUND:The recovery of function after spinal cord injury depends on the functional remodeling of the motor cortex.However,the anatomical evidence underlying the functional remodeling of the motor cortex is still illusive.Analyzing the anatomical changes in the motor cortex after spinal cord injury can provide new ideas and research directions for regulating functional recovery and rehabilitation after spinal cord injury. OBJECTIVE:To analyze the neural circuit structural basis of functional remodeling of the primary motor cortex after spinal cord injury. METHODS:C57BL/6J mice were randomly divided into a sham operation group and a spinal cord injury group.The adeno-associated virus vectors expressing the fusion protein of Cre recombinase were injected into C4 of mice of both groups.The adeno-associated virus vectors with Cre recombinase-inducible expression of avian sarcoma/leukosis envelope glycoprotein receptor TVA and rabies glycoprotein were injected into the primary motor cortex.Fourteen days later,a C6 dorsal hemisection mice model was established in the spinal cord injury group.The pseudotyped rabies virus was injected into the primary motor cortex of mice of both groups.After 7 days,brain samples were collected and frozen sections were made.The distribution of input neurons innervating corticospinal motor neurons in the brain was observed and analyzed quantitatively. RESULTS AND CONCLUSION:Fluorescence microscopy observation and quantitative analysis found that input neurons innervating corticospinal motor neurons of the primary motor cortex in mice of both groups were distributed in the cerebral cortex,thalamus and midbrain.Among them,in the sham operation group,the number of input neurons in the mouse cerebral cortex accounted for(84.0±3.6)%of total brain input neurons;that in the thalamus accounted for(10.6±2.3)%,and that in the midbrain accounted for(0.7±0.4)%.Direct synaptic input neurons in the spinal cord injury group accounted for(81.7±1.0)%,(13.1±0.5)%,and(1.6±0.8)%in the cerebral cortex,thalamus and midbrain,respectively.The proportion and number of primary motor cortex input neurons in the three regions of the spinal cord injury group did not differ significantly from that of the sham operation group.After spinal cord injury,the number of input neurons innervating corticospinal pyramidal motor neurons in various brain regions did not change significantly,suggesting that functional remodeling of the motor cortex after spinal cord injury may not only depend on changes in synaptic input related to injured corticospinal motor neurons,but also on transcriptional regulation changes within the injured neurons themselves.
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ObjectiveTo investigate the effect of multi-target transcranial direct current stimulation (tDCS) and single-target tDCS on the performance of working memory-postural control dual-task in healthy adults, and to compare the regulatory effect of the two stimulation protocols. MethodsFrom November, 2020 to February, 2021, 19 healthy adults in Shanghai University of Sport were recruited and randomly accepted multi-target tDCS, single-target tDCS and sham stimulation with at least one week interval between any two stimulation protocols. The target areas of multi-target tDCS included left dorsal lateral prefrontal cortex (L-DLPFC) and bilateral primary motor cortex (M1), and single-tDCS only applied to L-DLPFC. Before and after stimulation, participants completed walking and standing balance tests under single task and dual-task conditions with the second task being a N-back task. The dual-task postural control performance, dual-task cost (DTC) and working memory performance were observed before and after stimulation. ResultsSignificant differences were observed among three stimulation protocols in the changes of stride variability (F = 3.792, P = 0.029), DTC of stride variability (F = 3.412, P = 0.040) and velocity of center of pressure (Vcop) (F = 3.815, P = 0.029). The stride variability (P = 0.047) and Vcop (P = 0.015) were significantly lower and the decrease in DTC of stride variability tended to be significant (P = 0.073) following multi-target tDCS, as compared to sham stimulation. Single-target tDCS significantly decreased the changes of stride variability (P = 0.011), DTC of stride variability (P = 0.014) and Vcop (P = 0.025), as compared to sham stimulation. Compared with single target tDCS, multi-target tDCS reduced the changes of the dual-task cost of the area of center of pressure (P = 0.035). Moreover, no significant difference was observed among the three stimulation protocols in the changes of each measure in the working memory test (P > 0.05). ConclusionBoth multi-target tDCS and single-target tDCS can improve the performance of working memory-postural control dual-task in healthy adults, and compared with single-target tDCS, multi-target tDCS has some advantages in regulating postural control.
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Objective:To explore the short-term clinical efficacy and safety of high-frequency repetitive transcranial magnetic stimulation (hrTMS) in thalamic pain.Methods:A prospective study was performed; 41 patients with thalamic pain who received hrTMS in Department of Neurology, Anqing Medical Center Affiliated to Anhui Medical University from December 2022 to August 2023 were selected. According to different stimulation sites, these patients were divided into S2 group (intervening secondary sensory cortex of the unaffected side, n=21) and M1 group (intervening primary motor cortex of the unaffected side, n=20). Before treatment, at the 1 st weekend after pseudo-stimulation treatment and at the 1 st, 2 nd and 3 rd weeks after effective stimulation treatment, short-form McGill Pain Questionnaire (SF-MPQ) was performed, and N100 amplitude was monitored by myoelectric evoked potentiometer; adverse reactions during treatment cycles were observed. Results:(1) Compared with those before treatment, scores of sensory item, emotional item and visual analogue scale (VAS), and present pain intensity in S2 group were significantly decreased at the 2 nd and 3 rd weeks after effective stimulation treatment ( P<0.05). Compared with those before treatment, scores of sensory item and VAS, and present pain intensity in M1 group were significantly decreased at the 2 nd weeks after effective stimulation treatment, and scores of sensory item, emotional item and VAS, and present pain intensity in M1 group were significantly decreased at the 3 rd weeks after effective stimulation treatment( P<0.05). At the 3 rd weeks after effective stimulation treatment, compared with the M1 group, the S2 group had significantly decreased scores of sensory item, emotional item, and VAS, and present pain intensity (5.35±0.54 vs. 4.86±0.74; 3.55±0.69 vs. 3.14±0.57; 5.50±0.69 vs. 5.00±0.78; 2.20±0.42 vs. 1.81±0.41, P<0.05). (2) Compared with those before treatment, N100 amplitude in S2 group and M1 group was significantly increased at the 2 nd and 3 rd weeks after effective stimulation treatment ( P<0.05). At the 3 rd weeks after effective stimulation treatment, the S2 group had significantly higher N100 amplitude than the M1 group (3.43±0.60 vs. 3.00±0.65, P<0.05). (3) No adverse reactions such as seizure or scalp burning occurred in the 2 groups during the treatment cycles, without significant difference in headache or tinnitus incidences ( P>0.05). Conclusion:The hrTMS on secondary sensory cortex and primary motor cortex of the unaffected side can relief the short-term pain intensity in patients with thalamic pain, without obvious side effects; and hrTMS on secondary sensory cortex enjoys better effect.
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Objective:To observe any effect of magnetic stimulation of the primary motor cortex and sacral nerve roots on urinary retention after spinal cord injury.Methods:Forty patients experiencing urine retention after a spinal cord injury were randomly divided into an experimental group and a control group, each of 20. Both groups received conventional treatment and repeated magnetic stimulation of the roots of the sacral nerve. The experimental group also received repeated magnetic stimulation of the bilateral primary motor cortices (M1 region). Bladder capacity and pressure indices, residual urine volume and life quality were evaluated in both groups before and after 8 weeks of treatment.Results:After the treatment, the average maximum bladder pressure, first sensation capacity, residual urine volume and life quality score of both groups had improved significantly, but the improvements in average first sensation capacity, residual urine volume and life quality score of the experimental group were significantly greater than those of the control group. There was, however, no significant difference in the groups′ average maximum bladder pressure after the treatment.Conclusion:Magnetic stimulation of the primary motor cortex and sacral nerve roots can significantly improve the sensory function of the bladder, reduce residual urine volume and improve the life quality of persons experiencing urinary retention after a spinal cord injury.
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Excessive theta (θ) frequency oscillation and synchronization in the basal ganglia (BG) has been reported in elderly parkinsonian patients and animal models of levodopa (L-dopa)-induced dyskinesia (LID), particularly the θ oscillation recorded during periods when L-dopa is withdrawn (the off L-dopa state). To gain insight into processes underlying this activity, we explored the relationship between primary motor cortex (M1) oscillatory activity and BG output in LID. We recorded local field potentials in the substantia nigra pars reticulata (SNr) and M1 of awake, inattentive resting rats before and after L-dopa priming in Sham control, Parkinson disease model, and LID model groups. We found that chronic L-dopa increased θ synchronization and information flow between the SNr and M1 in off L-dopa state LID rats, with a SNr-to-M1 flow directionality. Compared with the on state, θ oscillational activity (θ synchronization and information flow) during the off state were more closely associated with abnormal involuntary movements. Our findings indicate that θ oscillation in M1 may be consequent to abnormal synchronous discharges in the BG and support the notion that M1 θ oscillation may participate in the induction of dyskinesia.
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Objective:To investigate the changes of metabolite concentration in the precentral gyrus (primary motor cortex, M1) in spinal cord injury (SCI) patients. Methods:From December, 2018 to October, 2019, 20 SCI patients and 15 healthy controls were scaned with magnetic resonance spectroscopy to measure the concentrations of N-acetylaspartate (NAA), choline (Cho), creatine (Cr) and myo-inositol (MI) in region of interest (ROI) of left M1. Results:Concentration of MI was more in the patients than in the controls (t = 3.745, P < 0.01). There was no significant difference in the concentrations of NAA, Cho and Cr, as well as the ratios of NAA/Cr, Cho/Cr, Cho/NAA between the patients and the controls (t < 1.431, P > 0.05). Conclusion:There may be hyperplasia of glial cells in M1 of SCI patients, indicating compensatory repair in cerebral motor cortex.
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Motor timing is an important part of sensorimotor control. Previous studies have shown that beta oscillations embody the process of temporal perception in explicit timing tasks. In contrast, studies focusing on beta oscillations in implicit timing tasks are lacking. In this study, we set up an implicit motor timing task and found a modulation pattern of beta oscillations with temporal perception during movement preparation. We trained two macaques in a repetitive visually-guided reach-to-grasp task with different holding intervals. Spikes and local field potentials were recorded from microelectrode arrays in the primary motor cortex, primary somatosensory cortex, and posterior parietal cortex. We analyzed the association between beta oscillations and temporal interval in fixed-duration experiments (500 ms as the Short Group and 1500 ms as the Long Group) and random-duration experiments (500 ms to 1500 ms). The results showed that the peak beta frequencies in both experiments ranged from 15 Hz to 25 Hz. The beta power was higher during the hold period than the movement (reach and grasp) period. Further, in the fixed-duration experiments, the mean power as well as the maximum rate of change of beta power in the first 300 ms were higher in the Short Group than in the Long Group when aligned with the Center Hit event. In contrast, in the random-duration experiments, the corresponding values showed no statistical differences among groups. The peak latency of beta power was shorter in the Short Group than in the Long Group in the fixed-duration experiments, while no consistent modulation pattern was found in the random-duration experiments. These results indicate that beta oscillations can modulate with temporal interval in their power mode. The synchronization period of beta power could reflect the cognitive set maintaining working memory of the temporal structure and attention.
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ABSTRACTThe central sulcus region is an eloquent area situated between the frontal and parietal lobes. During neurosurgical procedures, it is sometimes difficult to understand the cortical anatomy of this region.Objective Find alternative ways to anatomically navigate in this region during neurosurgical procedures.Method We analyzed eighty two human hemispheres using a surgical microscope and completed a review of the literature about central sulcus region.Results In 68/82 hemispheres, the central sulcus did not reach the posterior ramus of the lateral sulcus. A knob on the second curve of the precentral gyrus was reliably identified in only 64/82 hemispheres.Conclusion The morphometric data presented in this article can be useful as supplementary method to identify the central sulcus region landmarks.
RESUMOA região do sulco central é uma área eloquente posicionada entre os lobos frontal e parietal. Durante procedimentos neurocirúrgicos, em algumas ocasiões, torna-se difícil compreender a anatomia cortical desta região.Objetivo Encontrar métodos alternativos para uma navegaçāo anatômica desta regiāo durante procedimentos neurocirúrgicos.Método Analisamos oitenta e dois hemisférios humanos usando um microscópio cirúrgico, além de fazer uma revisão da literatura.Resultados Em 68/82 hemisférios, o sulco central não atingiu o ramo posterior do sulco lateral. Uma dilatação na segunda curva do giro precentral foi encontrada em apenas 64/82 hemisférios.Conclusão Os dados morfométricos apresentados neste artigo podem ser úteis como método suplementar para identificação dos reparos anatômicos na região do sulco central.
الموضوعات
Humans , Anatomic Landmarks/anatomy & histology , Frontal Lobe/anatomy & histology , Neurosurgical Procedures/methods , Parietal Lobe/anatomy & histology , Craniotomy , Magnetic Resonance Imaging , Neuroanatomy/methods , Reference Standardsالملخص
Reduction of excitability of the dominant primary motor cortex (M1) improves ipsilateral hand function in healthy subjects. In analogy, inhibition of non-dominant M1 should also improve ipsilateral performance. In order to investigate this hypothesis, we have used slow repetitive transcranial magnetic stimulation (rTMS) and the Purdue Pegboard test. Twenty-eight volunteers underwent 10 minutes of either 0.5Hz rTMS over right M1 or sham rTMS (coil perpendicular to scalp). The motor task was performed before, immediately after, and 20 minutes after rTMS. In both groups, motor performance improved significantly throughout the sessions. rTMS inhibition of the non-dominant M1 had no significant influence over ipsilateral or contralateral manual dexterity, even though the results were limited by unequal performance between groups at baseline. This is in contrast to an improvement in left hand function previously described following slow rTMS over left M1, and suggests a less prominent physiological transcallosal inhibition from right to left M1.
A redução da excitabilidade do córtex motor primário (M1) dominante melhora o desempenho manual ipsilateral: a inibição do M1 não-dominante poderia, analogamente, aprimorar a função manual direita. Para investigar esta hipótese, utilizou-se a estimulação magnética transcraniana repetitiva (EMTr) de baixa frequência e o teste Purdue Pegboard. Submetemos 28 voluntários a 10 minutos de EMTr sobre o M1 direito (0,5 Hz) ou a EMTr placebo (bobina perpendicular ao escalpo). O teste foi executado antes, imediatamente após e 20 minutos após a EMTr. Nos dois grupos, o desempenho manual mostrou significativa melhora entre as sessões. A inibição do M1 não-dominante não influenciou significativamente a destreza motora ipsi ou contralateral, apesar da conclusão limitada pelo desempenho discrepante dos grupos na primeira sessão. Este resultado contrasta com a melhora da função manual esquerda descrita após a EMTr sobre o M1 esquerdo e sugere uma inibição transcalosa fisiológica menos intensa do M1 direito para o esquerdo.
الموضوعات
Adolescent , Adult , Humans , Male , Young Adult , Functional Laterality/physiology , Hand/physiology , Motor Cortex/physiology , Psychomotor Performance/physiology , Transcranial Magnetic Stimulation/methods , Young Adultالملخص
Decreased number of the Neuropeptide-Y[NPY] immunoreactive neurons in the corpus striatum and primary motor cortex of aged rat was detected by the immunohistochemical method. The animals were categorized into control and aged group and we used 10 Sprague-Dawley rat weighing 250-300gm for control group. 10 Sprague-Dawley rat weighing over 600gm for aged group. The number of NPY-immunoreactive neurons in corpus striatum and primary motor cortex were counted under the light microscope and the following results were obtained. 1. The NPY-immunoreactive neurons were evenly distributed in corpus striatum and in the primaty motor cortex, the NPY-immunoreactive neurons were concentrated within the layer II, III and layer V, VI. The typical NPY-immunoreactive perikarya was multipolar shape. 2. Decreased number of NPY-immunoreactive neurons were detected in some areas of corpus striatum and primary mortor cortex of the aged rat. 3. Decrease of NPY-immunoreactive neurons were most prominent in the caudate-putamen and there were moderate decrease of NPY-immunoreactive neurons in the primary motor cortex, mild decrease of NPY-immunoreactive neurons in the nucleus accumbens but the NPY-immunoreactive neurons were not observed in the globus pallidus in both control and aged rat. NPY is supposed to act as a neurotransmitter of local circuit neurons in the striatum and may exert its potent vasoconstrictor effects on cerebral vessels which influences on the microcirculation of cerebral cortex and striatum. So our results seems to provide an important data on change of the function in the striatum and primary motor cortex of aged rat brain.