Transcranial temporal interference stimulation (tTIS) is a novel non-invasive transcranial electrical stimulation technique that achieves deep brain stimulation through multiple electrodes applying electric fields of different frequencies. Current studies on the mechanism of tTIS effects are primarily based on rodents, but experimental outcomes are often significantly influenced by electrode configurations. To enhance the performance of tTIS within the limited cranial space of rodents, we proposed various electrode configurations for tTIS and conducted finite element simulations using a realistic mouse model. Results demonstrated that ventral-dorsal, four-channel bipolar, and two-channel configurations performed best in terms of focality, diffusion of activated brain regions, and scalp impact, respectively. Compared to traditional transcranial direct current stimulation (tDCS), these configurations improved by 94.83%, 50.59%, and 3 514.58% in the respective evaluation metrics. This study provides a reference for selecting electrode configurations in future tTIS research on rodents.
In order to improve the accuracy and reliability of the electrodes implant location when using spinal functional electrical stimulation to rebuild hindlimb motor function, we measured the distributions of function core regions in rat spinal cord associated with hindlimb movements. In this study, we utilized three-dimensional scanning intraspinal microstimulation technology to stimulate the rat spinal cord to generate hip, knee and ankle joint movements, and acquired the coordinates of the sites in spinal cord which evoked these movements. In this article, 12 SD rats were used to overcome the individual differences in the functional region of the spinal cord. After normalized and overlaid the messages, we obtained the function core regions in spinal cord associated with ankle dorsiflexion movement, hip flexion movement, hip extension movement and hip adduction movement. It provides a reference for rebuilding the hindlimb movement function with micro-electronic neural bridge.
Objective To review the advances of functional electrical stimulation(FES) in treatment of peripheral nerve injuries. Methods By index of recent literature, the measures of stimulation, the mechanisms of FES and unsolved problems were evaluated and analyzed. Results Great advances have been made in the treatment of peripheral nerve injuries. It can not only enhance the regeneration of injured peripheral nerve, but also prevent muscular atrophy. Conclusion FES is an effective treatment for peripheral nerve injuries.
In recent years, the ongoing development of transcranial electrical stimulation (TES) and transcranial magnetic stimulation (TMS) has demonstrated significant potential in the treatment and rehabilitation of various brain diseases. In particular, the combined application of TES and TMS has shown considerable clinical value due to their potential synergistic effects. This paper first systematically reviews the mechanisms underlying TES and TMS, highlighting their respective advantages and limitations. Subsequently, the potential mechanisms of transcranial electromagnetic combined stimulation are explored, with a particular focus on three combined stimulation protocols: Repetitive TMS (rTMS) with transcranial direct current stimulation (tDCS), rTMS with transcranial alternating current stimulation (tACS), and theta burst TMS (TBS) with tACS, as well as their clinical applications in brain diseases. Finally, the paper analyzes the key challenges in transcranial electromagnetic combined stimulation research and outlines its future development directions. The aim of this paper is to provide a reference for the optimization and application of transcranial electromagnetic combined stimulation schemes in the treatment and rehabilitation of brain diseases.
ObjectivesTo systematically review the efficacy of pelvic floor electrical stimulation on urinary dysfunction.MethodsPubMed, EMbase, The Cochrane Library, CBM, CNKI, VIP and WanFang Data databases were searched to collect randomized controlled trials (RCTs) on the efficacy of pelvic floor electrical stimulation on urinary dysfunction from inception to August 2018. Two reviewers independently screened literature, extracted data and assessed risk of bias of included studies; then, meta-analysis was performed by using RevMan 5.3 software.ResultsA total of 9 RCTs involving 559 patients were included. The results of meta-analysis showed that the pelvic floor electrical stimulation group was superior to the control group in bladder volume before and after treatment(MD=79.25, 95%CI 40.36 to 118.15, P<0.000 1), residual urine volume (MD=35.50, 95%CI 7.60 to 63.41, P=0.01), maximum detrusor pressure (MD=5.19, 95%CI 2.11 to 8.27, P<0.001), number of leaks (RR=1.95, 95%CI 1.39 to 2.52, P<0.000 01), daily average urination frequency (RR=2.64, 95%CI 1.97 to 3.31, P<0.000 01), and international lower urinary tract score (MD=5.07, 95%CI 2.17 to 7.96, P=0.000 6).ConclusionsCurrent evidence shows that pelvic floor electrical stimulation is an effective therapy for urinary dysfunction. Due to limited quality and quantity of the included studies, more high quality-studies are required to verify the above conclusion.
Existing neuroregulatory techniques can achieve precise stimulation of the whole brain or cortex, but high-focus deep brain stimulation has been a technical bottleneck in this field. In this paper, based on the theory of negative permeability emerged in recent years, a simulation model of magnetic replicator is established to study the distribution of the induced electric field in the deep brain and explore the possibility of deep focusing, which is compared with the traditional magnetic stimulation method. Simulation results show that a single magnetic replicator realized remote magnetic source. Under the condition of the same position and compared with the traditional method of stimulating, the former generated smaller induced electric field which sharply reduced with distance. By superposition of the magnetic field replicator, the induced electric field intensity could be increased and the focus could be improved, reducing the number of peripheral wires while guaranteeing good focus. The magnetic replicator model established in this paper provides a new idea for precise deep brain stimulation, which can be combined with neuroregulatory techniques in the future to lay a foundation for clinical application.
Objective To systematically evaluate the orthotic effect of functional electrical stimulation (FES) on the improvement of walking in stroke patients with foot drop. Methods The randomized controlled trials (RCTs) that investigated the orthotic effect of FES on walking in stroke patients with foot drop were electronically searched in the databases such as PubMed, Web of Science, The Cochrane Library (Issue 1, 2013), EMbase, CBM, CNKI, VIP and WanFang Data from January 2000 to January 2013, and the relevant references of included papers were also manually searched. Two reviewers independently screened the trials according to the inclusion and exclusion criteria, extracted the data, and assessed the methodology quality. The meta-analyses were performed using RevMan 5.1 software. Results A total of 8 RCTs involving 255 patients were included. The results of meta-analyses on 4 RCTs showed that, compared with the conventional rehabilitation intervention, the functional electrical stimulation could significantly improve the walking speed, with significant difference (MD=0.09, 95%CI 0.00 to 0.18, P=0.04). The other indicators were only descriptively analyzed due to the incomplete data. Conclusions Functional electrical stimulation is effective in improving walking speed, but it is uncertain of other therapeutic indicators. So it should be further proved by conducting more high quality, large sample and multi-center RCTs.
Bone marrow-derived mesenchymal stem cells (BMSCs) for repairing damaged heart tissue are a new kind of important treatment options because of their potential to differentiate into cardiomyocytes. We in this experiment investigated the effect of different electrical stimulation time on the expression of myocardial specificity gene and protein in rat bone marrow mesenchymal stem cells (rBMSCs) in vitro. The rBMSCs of second or third generation were randomly divided into three groups, i.e. electrical stimulation (ES) group, 5-Azacytidine (5-Aza) group and the control group. The rBMSCs in the ES groups with complete medium were exposed to 2 V, 2 Hz, 5 ms electrical stimulation for 0.5 h, 2 h, 4 h, and 6 h respectively every day for 10 days. Those in the 5-Aza group were induced by 5-Aza (10 μmol/L) for 24 h, and then cultured with complete medium for 10 days. Those in the control group were only cultured with complete medium, without any treatment, for 10 days. The rBMSCs' morphological feature in each group was observed with inverted phase microscope. The mRNA expression of myocyte-specific enhancer factor 2C (MEF-2C) and connexin 43 (Cx43) were examined with Real-Time quantitative PCR and the protein expression of MEF-2C, Cx43 were detected with Western Blot method. The results showed that the mRNA expression level of the MEF-2C, Cx43 and the protein expression level of MEF-2C, Cx43 were significantly higher in the ES group and 5-Aza group than those in the relative control group (P < 0.05). It suggests that electrical stimulation could play a part of role in the induction of the rBMSCs to differentiate into the cariomyocyte-like cells in vitro and the effectiveness of the electrical stimulation with 2 h/d had the best in our experiement. But the mechanism how electrical stimulation promotes the differentiation of rBMSC into cardiomyocyte is still unclear.
In order to investigate the effect of deep brain stimulation on diseases such as epilepsy, we developed a closed-loop electrical stimulation system using LabVIEW virtual instrument environment and NI data acquisition card. The system was used to detect electrical signals of epileptic seizures automatically and to generate electrical stimuli. We designed a novel automatic detection algorithm of epileptic seizures by combining three features of field potentials: the amplitude, slope and coastline index. Experimental results of rat epileptic model in the hippocampal region showed that the system was able to detect epileptic seizures with an accuracy rate 91.3% and false rate 8.0%. Furthermore, the on-line high frequency electrical stimuli showed a suppression effect on seizures. In addition, the system was adaptive and flexible with multiple work modes, such as automatic and manual modes. Moreover, the simple time-domain algorithm of seizure detection guaranteed the real-time feature of the system and provided an easy-to-use equipment for the experiment researches of epilepsy control by electrical stimulation.
Neuromuscular electrical stimulation (NMES) has been proven to promote human balance, but research on its impact on motor ability mainly focuses on external physical analysis, with little analysis on the intrinsic neural regulatory mechanisms. This study, for the first time, investigated the effects of NMES on cortical activity and cortico-muscular functional coupling (CMFC) during standing balance. Twelve healthy subjects were recruited in bilateral NMES training, with each session consisting of 60 electrically induced isometric contractions. Electroencephalogram (EEG) signals, electromyogram (EMG) signals, and center of pressure (COP) signals of the foot sole were collected before stimulation, two weeks after stimulation, and four weeks after stimulation while the subjects maintained standing balance. The results showed that NMES training improved subjects' postural stability during standing balance. Additionally, based on the EMG power spectral density (PSD), the κ frequency band was defined, and EEG-EMG time-frequency maximal information coefficients (TFMIC) were calculated. It was found that NMES enhanced functional connectivity between the cortex and lower limb muscles, with varying degrees of increase in β-κ and γ-κ frequency band CMFC after stimulation. Furthermore, sample entropy (SE) of EEG signals also increased after training. The results of this study confirm that NMES training can enhance CMFC and brain activation during standing balance. This study, from the perspective of physiological electrical signals, validates the effectiveness of NMES for balance training and provides objective assessment metrics for the training effects of NMES.