As a noninvasive neuromodulation technique, transcranial magnetic stimulation (TMS) is widely used in the clinical treatment of neurological and psychiatric diseases, but the mechanism of its action is still unclear. The purpose of this paper is to investigate the effects of different frequencies of magnetic stimulation (MS) on neuronal excitability and voltage-gated potassium channels in the in vitro brain slices from the electrophysiological perspective of neurons. The experiment was divided into stimulus groups and control group, and acute isolated mice brain slices were applied to MS with the same intensity (0.3 T) at different frequencies (20 Hz and 0.5 Hz, 500 pulses) respectively in the stimulus groups. The whole-cell patch clamp technique was used to record the resting membrane potential (RMP), action potential (AP), voltage-gated potassium channels current of hippocampal dentate gyrus (DG) granule cells. The results showed that 20 Hz MS significantly increased the number of APs released and the maximum slope of a single AP, reduced the threshold of AP, half width and time to AP peak amplitude, and improved the excitability of hippocampal neurons. The peak currents of potassium channels were decreased, the inactivation curve of transient outward potassium channels shifted to the left significantly, and the time constant of recovery after inactivation increased significantly. 0.5 Hz MS significantly inhibited neuronal excitability and increased the peak currents of potassium channels, but the dynamic characteristics of potassium channels had little change. The results suggest that the dynamic characteristics of voltage-gated potassium channels and the excitability of hippocampal DG granule neurons may be one of the potential mechanisms of neuromodulation by MS.
ObjectiveTo observe the efficacy of high-frequency repetitive transcranial magnetic stimulation (rTMS) applied at contralesional hemisphere Broca’s homologue on patients with global aphasia after left massive cerebral infarction. Methods Patients with global aphasia after left massive cerebral infarction in the Department of Neurorehabilitation of China Rehabilitation Research Center between August 2021 and December 2023 were selected. According to the random number table method, patients were randomly divided into a low-frequency rTMS group and a high-frequency rTMS group. rTMS targeted the mirror area within the right hemispheric Broca’s area. Patients’ language ability was assessed pre- and post-treatment by the Chinese version of the western aphasia battery (WAB). Results A total of 27 patients were included, with 14 in the low-frequency rTMS group and 13 in the high-frequency rTMS group. Before treatment, there was no statistically significant difference in the WAB test indicators between the two groups of patients (P>0.05). After treatment, WAB scores (spontaneous speech, auditory comprehension, naming, repetition, aphasia quotients) in both groups were significantly improved (P<0.05); compared to the low-frequency rTMS group, the high-frequency rTMS group exhibited significant improvement in spontaneous speech, auditory comprehension, repetition, naming and aphasia quotients (P<0.05). Conclusion The effect of high-frequency rTMS excitation to contralesional hemisphere is better than that of conventional low-frequency rTMS inhibition to contralesional hemisphere in improving the speech function of patients with global aphasia after left massive cerebral infarction.
The aim of this study is to explore the effects of continuous theta-burst transcranial magnetic stimulation (cTBS) on functional brain network in emotion processing. Before and after the intervention of cTBS over left dorsolateral prefrontal cortex (DLPFC) of ten participants who were asked to perform the emotion gender recognition task, we recorded their scalp electroencephalograms (EEG). Then we used the phase synchronization of EEG to measure the connectivity between two nodes. We then calculated the network efficiency to describe the efficiency of information transmission in brain regions. Our research showed that after the intervention of cTBS and the stimulation of the emotion face picture, there was an obvious enhancement in the event-related spectral perturbation after stimuli onset in beta band in 100–300 ms. Under the stimulation of different emotion picture, the values of global phase synchronization for negative and neutral stimuli were enhanced compared to positive ones. And the increased small-worldness was found in emotional processing. In summary, based on the effect of activity change in the left DLPFC on emotion processing brain network, the emotional processing mechanism of brain networks were preliminary explored and it provided the reference for the research of emotion processing brain network in the future.
Parkinson’s disease is a neurodegenerative disease that mostly occurs in middle-aged and elderly people. It is characterized by progressive loss of dopaminergic neurons in the substantia nigra and aggregation of Lewy bodies, resulting in a series of motor symptoms and non-motor symptoms. Depression is the most important manifestation of non-motor symptoms, which seriously affects the quality of life of patients. Clinicians often use antidepressant drugs to improve the depressive symptoms of patients with Parkinson 's disease, but it is still urgent to solve the problems of drug side effects and drug resistance caused by such methods. Repetitive transcranial magnetic stimulation is a safe and non-invasive neuromodulation technique that can change the excitability of the corticospinal tract, induce the release of dopamine and other neurotransmitters, and further improve the depressive symptoms of patients with Parkinson 's disease. Based on this, this paper discusses and summarizes the research progress on the efficacy and potential mechanism of repetitive transcranial magnetic stimulation for improving depression in Parkinson 's disease at home and abroad, in order to provide reference for related clinical application research.
Objective To evaluate the systematic reviews of repetitive transcranial magnetic stimulation (rTMS) for insomnia, to provide supporting evidence for clinical practice. Methods PubMed, Embase, Web of Science, Cochrane Library, Elsevier Science Direct, China National Knowledge Infrastructure, SinoMed, Wanfang and Chongqing VIP were searched from databases establishment to May 30, 2022, to find systematic reviews on the treatment of insomnia with rTMS as the main method. The methodological quality, reporting quality and evidence quality of outcome indicators were evaluated by AMSTAR 2, PRISMA 2020 and GRADE. Results A total of 4 systematic reviews published between 2018 and 2021 were included. Further analysis showed that one of the systematic reviews had a low AMSTAR 2 quality rating and the remaining systematic reviews were very low. The average PRISMA 2020 score of these 4 systematic reviews was (20.75±3.27) points, of which 3 systematic reviews had some defects in their reports, and the other one had relatively complete reports. The GRADE evidence quality assessment showed that there were 40 outcome indicators in the included literature, of which 3 outcome indicators (sleep quality, the percentage of S2 sleep in total sleep time, and S3 sleep in percentage of total sleep time) were rated as moderate, 17 were rated as low and 20 were rated as very low. Conclusions The treatment of insomnia by rTMS has achieved certain effects in clinical practice, but the systematic review of rTMS as the main intervention measure for insomnia needs to further improve the quality and standardize related research. The clinical application of rTMS for insomnia should be treated as appropriate.
In the treatment of drug-refractory epilepsy in children, surgical treatment has a good clinical effect. However, for children whose surgical site is difficult to determine and who cannot undergo resectional surgery, neuromodulation techniques are one of the treatments that can be considered. At present, new neuromodulation technologies in children mainly include transcutaneous vagus nerve stimulation (transcutaneous auricular vagus nerve stimulation, ta-VNS), deep brain stimulation (deep brain stimulation, DBS), reactive nerve stimulation (responsive neurostimulation, RNS), transcranial magnetic stimulation (transcranial magnetic stimulation, TMS), transcranial direct current stimulation (transcranial direct current stimulation, TDCS) and transcranial alternating current stimulation (transcranial alternating current stimulation, TACS). This article briefly discussed the clinical efficacy and safety of various currently available neuromodulation technologies, so as to provide a reference for the rational selection and application of neuromodulation technologies, and improve the clinical efficacy and quality of life of children with drug-refractory epilepsy.
Objective To evaluate the effectiveness of repetitive transcranial magnetic stimulation (rTMS) for treating dysfunction in patients with Parkinson’s disease (PD). Methods We searched the Cochrane Library (Issue 1, 2010), MEDLINE, EMbase, CBMdisc, and CNKI from the date of the database establishment to April 2010. Randomized controlled trials (RCTs) of rTMS for patients with PD were collected. The quality of the included RCTs was critically appraised and data were extracted by two reviewers independently. Meta-analyses were conducted for the eligible RCTs. Results Eight RCTs were included. The pooled results of the first 2 RCTs showed that, there was no significant difference compared with control group about treating PD patients with clinical motor dysfunction by high-frequency rTMS 10 days later (WMD= –4.75, 95%CI –13.73 to 4.23). The pooled analysis of another 3 studies showed that, no significant difference were found about improving symptoms with treatment of low-frequency rTMS for 1 month compared with control group (WDM= –8.51, 95%CI –18.48 to 1.46). The pooled analysis of last 3 studies showed that, patient with treatment of low-frequency rTMS for 3 months, had been significantly improved in clinical symptoms such as neurological, behavior and emotional state, clinical motor function, and activities of daily living (WDM= –5.79, 95%CI –8.44 to –1.13). The frontal or motor cortex rTMS manifested as low frequency (≤1Hz), high intensity (≥90% RMT), multi-frequency (≥3 times) and long time (≥3 months) had a positive effect on the clinical symptoms of patients with PD and also had a long-term effect. Conclusions rTMS can improve clinical symptoms and dysfunction of the patients with PD.
Repetitive transcranial magnetic stimulation(rTMS) is a painless and non-invasive method for stimulation and modulation in the field of cognitive neuroscience research and clinical neurological regulation. In this paper, adult Wistar rats were divided into the rTMS group and control group randomly. Rats in the rTMS group were stimulated with 5 Hz rTMS for 14 days, while the rats in the control group did not accept any stimulation. Then, the behavior and local field potentials (LFPs) were recorded synchronously when the rats perform a working memory (WM) task with T-maze. Finally, the time-frequency distribution and coherence characteristics of the LFPs signal in the prefrontal cortex (PFC) during working memory task were analyzed. The results showed that the rats in the rTMS group needed less training days to reach the task correction criterion than the control group (P < 0.05). Compared with the control group, the rTMS group has higher energy (P < 0.01) in θ band (4~12 Hz) and γ band (30~80 Hz). The coherence between the channel pairs decreases as the spatial distance of the channel pairs increases, and the rTMS group exhibits a higher coherence than the control group (P < 0.01). It is concluded that 5 Hz rTMS can improve the excitability of rat prefrontal cortical neurons to a certain extent, and has a positive effect on the working memory ability of normal rats. The results of this paper may provide important theoretical support for further research on the mechanism of action of rTMS on WM.
Stroke has the characteristics of high incidence rate, high mortality rate and high disability rate. Most patients may have some motor dysfunction after stroke, which greatly affects the normal life of patients. As a common sequela after stroke, foot drop seriously affects the walking gait of patients, limits the activities of patients, and reduces their quality of life. In recent years, repetitive peripheral magnetic stimulation (rPMS) has been used more and more in the rehabilitation of various diseases. Because rPMS is noninvasive, affordable and effective, it is accepted by many patients. This article reviews the research progress of rPMS for foot drop after stroke.
Transcranial magnetic stimulation (TMS) combined with electroencephalography(EEG) has become an important tool in brain research. However, it is difficult to remove the large artifacts in EEG signals caused by the online TMS intervention. In this paper, we summed up various types of artifacts. After introducing a variety of online methods, the paper emphasized on offline approaches, such as subtraction, principal component analysis and independent component analysis, which can remove or minimize TMS-induced artifacts according to their different characteristics. Although these approaches can deal with most of the artifacts induced by TMS, the removal of large artifacts still needs to be improved. This paper systematically summarizes the effective methods for artifacts removal in TMS-EEG studies. It is a good reference for TMS-EEG researchers while choosing the suitable artifacts removal methods.