ObjectiveTo systematically review the efficacy of three transcranial direct current stimulation protocols (anodal stimulation, cathodal stimulation, and bipolar stimulation) on upper extremity function interventions in stroke patients. MethodsPubMed, EMbase, The Cochrane Library, Web of Science, CNKI, CBM, WanFang Data and VIP databases were electronically searched to collect randomized controlled trials (RCTs) on the efficacy of three transcranial direct current stimulation protocols on upper extremity function interventions in stroke patients from inception to April 2022. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies; then, the network meta-analysis was performed by using R software and ADDIS software. ResultsA total of 64 RCTs involving 3 968 patients were included. The results of network meta-analysis showed that, the probability order of the three stimulation methods on FMA-U, MBI, NIHSS score was: anode>bipolar>cathode>control. In addition, the probability order on ARAT and BBT score was: anode>cathode>bipolar>control. ConclusionCurrent evidence shows that the intervention effect of anodic stimulation on upper limb function of stroke patients may be better. Due to limited quality and quantity of the included studies, more high-quality studies are needed to verify above conclusion.
Motor imagery is often used in the fields of sports training and neurorehabilitation for its advantages of being highly targeted, easy to learn, and requiring no special equipment, and has become a major research paradigm in cognitive neuroscience. Transcranial direct current stimulation (tDCS), an emerging neuromodulation technique, modulates cortical excitability, which in turn affects functions such as locomotion. However, it is unclear whether tDCS has a positive effect on motor imagery task states. In this paper, 16 young healthy subjects were included, and the electroencephalogram (EEG) signals and near-infrared spectrum (NIRS) signals of the subjects were collected when they were performing motor imagery tasks before and after receiving tDCS, and the changes in multiscale sample entropy (MSE) and haemoglobin concentration were calculated and analyzed during the different tasks. The results found that MSE of task-related brain regions increased, oxygenated haemoglobin concentration increased, and total haemoglobin concentration rose after tDCS stimulation, indicating that tDCS increased the activation of task-related brain regions and had a positive effect on motor imagery. This study may provide some reference value for the clinical study of tDCS combined with motor imagery.
Transcranial direct current stimulation (tDCS) is a non-invasive technique that uses constant low-intensity direct current (1 to 2 mA) to regulate neuronal activity in the cerebral cortex. In recent years, tDCS has received more and more attention as a tool to explore human brain function and treat various neurological diseases. However, there is still a lack of systematic and comprehensive reviews in the tDCS treatment of post-stroke dysfunction. This article reviews the treatment of post-stroke dysfunction with tDCS, integrates relevant basic research and clinical research in recent years, summarizes and discusses the theoretical mechanism and application effect of tDCS in the treatment of post-stroke dysfunction, so as to provide a basis for further research.
As an emerging non-invasive brain stimulation technique, transcranial direct current stimulation (tDCS) has received increasing attention in the field of stroke disease rehabilitation. However, its efficacy needs to be further studied. The tDCS has three stimulation modes: bipolar-stimulation mode, anode-stimulation mode and cathode-stimulation mode. Nineteen stroke patients were included in this research (10 with left-hemisphere lesion and 9 with right). Resting electroencephalogram (EEG) signals were collected from subjects before and after bipolar-stimulation, anodal-stimulation, cathodal-stimulation, and pseudo-stimulation, with pseudo-stimulation serving as the control group. The changes of multi-scale intrinsic fuzzy entropy (MIFE) of EEG signals before and after stimulation were compared. The results revealed that MIFE was significantly greater in the frontal and central regions after bipolar-stimulation (P < 0.05), in the left central region after anodal-stimulation (P < 0.05), and in the frontal and right central regions after cathodal-stimulation (P < 0.05) in patients with left-hemisphere lesions. MIFE was significantly greater in the frontal, central and parieto-occipital joint regions after bipolar-stimulation (P < 0.05), in the left frontal and right central regions after anodal- stimulation (P < 0.05), and in the central and right occipital regions after cathodal-stimulation (P < 0.05) in patients with right-hemisphere lesions. However, the difference before and after pseudo-stimulation was not statistically significant (P > 0.05). The results of this paper showed that the bipolar stimulation pattern affected the largest range of brain areas, and it might provide a reference for the clinical study of rehabilitation after stroke.
ObjectiveTo investigate the effect of anodal transcranial direct current stimulation (tDCS) combined with rehabilitation interventions on the patients suffering from motor dysfunction after traumatic spinal cord injury (SCI).MethodsTwo hundred and twenty-five patients with SCI from September 2015 to November 2018 were retrospectively included in this study. According to their accepted rehabilitation interventions, patients were divided into the intervention group and the control group. In the control group, the patients just accepted routine rehabilitation interventions, including movement therapy on limbs, physical therapy and acupuncture, while the patients in the intervention group accepted anodal tDCS combined with routine interventions (the same as the control group). The baseline between the two groups was similar. Moreover, subgroup analysis including trauma site and extent were carried out for further exploration for the positive effect of tDCS on motor function suffering from acute traumatic SCI. American Spinal Injury Association (ASIA) motor item, Functional IndependenceMeasure (FIM) and modified Barthel index (MBI), as well as motor evoked potential (MEP) were carried out for the evaluation of motor function ahead of and 30 days after intervention.ResultsAfter 30-day rehabilitation intervention, the scores of ASIA motor item (48.26±6.57), FIM (60.68±6.05) and MBI (68.73±7.57) were all significantly higher in the intervention group than those in the control group (all P<0.05). Besides, MEP latency of C7 [(9.20±0.42) ms], hand area [(17.81±0.56) ms], Pf [(3.24±0.47) ms] and leg area [(23.06±0.98) ms], as well as central motor conduction time of upper limbs [(6.08±0.50) ms] and lower limbs [(18.06±0.99) ms] were all significantly lower in the intervention group than those in the control group (P<0.05). In addition, the subgroup analyses based on injury site and injury extent also showed that anodal tDCS associated with better motor recovery, in that the scores of ASIA motor item, FIM and MBI were all significantly higher in the intervention group than those in the control group (P<0.05), while the MEP central motor conduction time of upper limbs and lower limbs were all significantly lower in the intervention group than those in the control group (P<0.05).ConclusionAnodal tDCS could distinctly promote the recovery of motor function in patients suffering from motor dysfunction after traumatic SCI, indicating that anodal tDCS may play an important role in the rehabilitation intervention for neurological dysfunction.
Transcranial direct current stimulation (tDCS) is an important method for treating mental illnesses and neurodegenerative diseases. This paper reconstructed two ex vivo brain slice models based on rat brain slice staining images and magnetic resonance imaging (MRI) data respectively, and the current densities of hippocampus after cortical tDCS were obtained through finite element calculation. Subsequently, a neuron model was used to calculate the response of rat hippocampal pyramidal neuron under these current densities, and the neuronal responses of the two models under different stimulation parameters were compared. The results show that a minimum stimulation voltage of 17 V can excite hippocampal pyramidal neuron in the model based on brain slice staining images, while 24 V is required in the MRI-based model. The results indicate that the model based on brain slice staining images has advantages in precision and electric field propagation simulation, and its results are closer to real measurements, which can provide guidance for the selection of tDCS parameters and scientific basis for precise stimulation.