Low-frequency rTMS Research Articles

Repetitive transcranial magnetic stimulation therapy for motor recovery in Parkinson's disease: A Meta-analysis.

IntroductionTherapeutic effects of repetitive transcranial magnetic stimulation (rTMS) on motor recovery of Parkinson's disease (PD) have been reported; however, the protocols of these studies varied greatly. The aim of this meta‐analysis was to evaluate the optimal rTMS parameters for motor recovery of PD.MethodsElectronic databases were searched for studies investigating the therapeutic effects of rTMS on motor function in patients with PD. The section III of the Unified Parkinson's Disease Rating Scale (UPDRS) was extracted as the primary outcome, and the standardized mean difference (SMD) with 95% confidence interval (CI) was calculated.ResultsTwenty‐three studies with a total of 646 participants were included. The pooled estimates of rTMS revealed significant short‐term (SMD, 0.37; p < 0.00001) and long‐term (SMD, 0.39; p = 0.005) effects on motor function improvement of PD. Subgroup analysis observed that high‐frequency rTMS (HF‐rTMS) was significant in improving motor function (SMD, 0.48; p < 0.00001), but low‐frequency rTMS (LF‐rTMS) was not. In particular, when HF‐rTMS targeted over the primary motor cortex (M1), in which the bilateral M1 revealed a larger effect size than unilateral M1. Compared to single‐session, multi‐session of HF‐rTMS over the M1 showed significant effect size. In addition, HF‐rTMS over the M1 with a total of 18,000–20,000 stimulation pulses yielded more significant effects (SMD, 0.97; p = 0.01) than other dosages.ConclusionsIn conclusion, multi‐session of HF‐rTMS over the M1 (especially bilateral M1) with a total of 18,000–20,000 pulses appears to be the optimal parameters for motor improvement of PD.

Repetitive Transcranial Magnetic Stimulation changes absolute theta power during cognitive/motor tasks

Repetitive Transcranial Magnetic Stimulation (rTMS) studies are used to test motor imagery hypothesis. Motor Imagery (MI) represents conscious access to contents of movement intention, generally executed unconsciously during motor preparation. The main objective of this study was to investigate electrophysiological changes, which occurred before and after low-frequency rTMS application when we compared three different tasks: execution, action observation and motor imagery of finger movement. We hypothesize that absolute theta power over frontal regions would change between sensorimotor integration tasks and after 1 Hz of rTMS application. Eleven healthy, right-handed volunteers of both sexes (5 males, 6 females; mean age 28 ± 5 years), with no history of psychiatric or neurological disorders, participated in the experiment. After performing the tasks randomly, subjects were submitted to 15 min of low-frequency rTMS applied on Superior Parietal Cortex (SPC) and performed the tasks again. All tasks were executed simultaneously with Eletroencephalography (EEG) signals recording. Our results clarified the specificity of each sub-region during MI activity. Frontopolar cortex presented involvement with motor process and showed main effect for task and moment. Inferior frontal gyrus presented involvement with long-term memory retrieval and showed interaction between task and moment in the left hemisphere while the right hemisphere showed a main effect for task and moment. The lack of the main effect for conditions on the anterior frontal cortex collaborates with the hypothesis that in this region an integrated circuit of performance monitoring exists.

Effects of low- and high-frequency repetitive transcranial magnetic stimulation on long-latency auditory evoked potentials

Long-latency auditory event potentials (LLAEPs) involving local and global auditory processes have been investigated to examine the impact of low-frequency (LF) and high-frequency (HF) repetitive transcranial magnetic stimulation (rTMS) on the cortical excitability of the temporal cortex. We hypothesized that both stimulation frequencies have the same modulation effect, in accordance with clinical data showing a reduction in auditory verbal hallucinations (AVHs) after LF and HF temporal rTMS in patients with schizophrenia. With 30 right-handed healthy volunteer participants enrolled in a crossover trial, we analyzed LLAEPs before and after LF- and HF-rTMS of the left temporal cortex. While we observed no changes in latencies, we did observe a similar inhibitory action of both rTMS frequencies on LLAEP amplitudes. Analysis of surface potential maps and cortical generators revealed some differences regarding auditory processes: HF-rTMS produced earlier, more diffuse, and more right-lateralized effects than LF-rTMS. Beyond a local impact, rTMS exerted a remote modulation influence on the frontal cortex that might be involved in attentional processes. This association could explain the therapeutic effect of temporal HF-rTMS on AVH.

Response and Remission Rates Following High-Frequency vs. Low-Frequency Repetitive Transcranial Magnetic Stimulation (rTMS) Over Right DLPFC for Treating Major Depressive Disorder (MDD): A Meta-Analysis of Randomized, Double-Blind Trials

Background: High-frequency (HF) repetitive transcranial magnetic stimulation (rTMS) over the left dorsolateral prefrontal cortex (L-DLPFC) is the most widely applied treatment protocol for major depressive disorder (MDD), while low-frequency (LF) rTMS over the right DLPFC (R-DLPFC) also exhibits similar, if not better, efficacy for MDD. Therefore, a meta-analysis is warranted to compare the efficacy of the two protocols for MDD.Method: We searched the literature from 1990 through to August 1, 2017 using MEDLINE, and the literature from 1995 through to August 1, 2017 using EMBASE, PsycINFO, the Cochrane Central Register of Controlled Trials (CENTRAL), SCOPUS, and ProQuest Dissertations and Theses (PQDT). We included randomized controlled trials (RCT) comparing the efficacy of HF rTMS over the L-DLPFC and LF rTMS over the R-DLPFC for MDD, which used response and/or remission rates as the primary endpoints, with and without sham-controlled.Results: (1) The meta-analysis of the response rates was based on 12 studies, including 361 patients with MDD (175 for HF (> 5 Hz) over the L-DLPFC, and 186 for LF (<5 Hz) over the R-DLPFC; odds ratio = 1.08; 95%, confidence interval = 0.88–1.34). (2) The meta-analysis of the remission rate was based on 5 studies, including 131 MDD patients (64 for HF over the L-DLPFC and 67 for LF over the R-DLPFC; odds ratio = 1.29; 95% confidence interval = 0.54–3.10).Conclusion: Both HF rTMS over the L-DLPFC and LF over the R-DLPFC demonstrated similar therapeutic efficacy for the treatment of patients with MDD. The results suggested that further investigation on treatment efficacy indicators before/during treatment is necessary and helpful for optimizing a personalized protocol for patients.

Effects of Hand Training During the Aftereffect Period of Low-Frequency rTMS in Subacute Stroke Patients.

ObjectiveTo investigate the effects of hand training using low-frequency repetitive transcranial magnetic stimulation (rTMS) within the aftereffect period on hand function in patients with subacute stroke.MethodsThe subacute stroke patients with hand weaknesses were divided randomly into two groups. Patients in the intervention group underwent hand training within the aftereffect period, that is, immediately after receiving low-frequency rTMS treatment. Patients in the control group underwent hand training 2 hours after the low-frequency rTMS treatment. A manual function test (MFT) for ‘grasp and pinch’ and ‘hand activities’; a manual muscle test (MMT) for ‘grasp’, ‘release’, and ‘abductor pollicis brevis (APB)’; and the Modified Ashworth Scale for finger flexion were performed and measured before and immediately after combined therapy as well as 2 weeks after combined therapy.ResultsThirty-two patients with hand weakness were enrolled in this study. The intervention group patients showed more improvements in grasp MMT and MMT APB tested immediately after combined therapy. However, the changes in all measurements were not significantly different between the two groups 2 weeks after the combined therapy. In both groups, hand functions improved significantly immediately after combined therapy and 2 weeks after combined therapy.ConclusionHand training immediately after low-frequency rTMS showed more rapid improvement in the motor power of hands than hand training conducted 2 hours after low-frequency rTMS. Our results suggest that conducting hand training immediately after low-frequency rTMS could be an improved useful therapeutic option in subacute stroke patients.

Low-frequency repetitive transcranial magnetic stimulation inhibits the development of methamphetamine-induced conditioned place preference

The abuse of amphetamine-type stimulants (ATS) has become a global public health issue in recent years, these new-type drugs can cause addiction and serious cognitive impairment. However, there are no effective methods for the prevention and treatment of ATS addiction at present. Repetitive transcranial magnetic stimulation (rTMS) is a painless and non-invasive new therapeutic approach that has been used for the treatment of depression and other neuropsychiatric disorders, but whether it can be used to treat drug addiction is unclear. In the present study, we investigated the possible effects of rTMS on methamphetamine(METH)-induced conditioned place preference (CPP). High-frequency (10 Hz) and low-frequency stimulation patterns (1 Hz) were applied to test the effect of rTMS on METH-induced CPP. The results showed that low-frequency but not high-frequency rTMS could block METH-CPP, accompanied with a downregulation of gamma-aminobutyric acid type B receptor subunit 1 (GABABR1) expression in rat dorsolateral striatum. These results suggested that low-frequency rTMS could effectively inhibit the development of METH addiction and shed light on the rTMS as a potential approach for the prevention of drug addiction.

PB13. Is 0.9 Hz rTMS-induced LTD-like corticospinal plasticity dependent on [formula omitted]-rhythm phase during the intervention?

Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive method to stimulate the human brain. It is capable of inducing plasticity and altering the state of the brain. The method is widely used by clinicians and neuroscientists alike and has increasing experimental, diagnostic and therapeutic applications. Yet so far, it often suffers from a considerable variability and low effect size. Low-frequency rTMS of the primary motor cortex at near 1 Hz (0.9 Hz) induced long-term depression (LTD)-like effects on corticospinal excitability (Chen et al., 1997). It was recently demonstrated that corticospinal excitability as well as induction of long-term potentiation (LTP)-like plasticity effects depend on the phase of the 8–12 Hz alpha oscillation of the somatosensory cortex ( μ -alpha oscillation) at the time of stimulation. LTP-like corticospinal plasticity resulted from real-time EEG-triggered 100 Hz burst rTMS during the negative but not positive peak of the μ -alpha oscillation (Zrenner et al., under revision). Since LTD-like plasticity of near 1 Hz rTMS was examined in random phase (‘open loop’) rTMS protocols only so far, it is unknown, whether the observed effect is dependent on a phase of the μ -alpha oscillation and by which phase it might be controlled. Here we address this question using a real-time EEG-triggered TMS set-up. Motor evoked potentials (MEPs) are recorded from right hand muscles before and after a phase-triggered 15-min 0.9 Hz rTMS intervention in a double-blind randomized cross-over design: Each subject will undergo three phase conditions in the 0.9 Hz intervention: (1) random phase stimulation, (2) stimulation triggered by the EEG positive peak and (3) stimulation triggered by the negative peak of the ongoing μ -rhythm. The results of this study will show whether μ -oscillation phase modules LTD-like corticospinal excitability induced by rTMS near 1 Hz. They will have substantial implications for understanding the neurophysiology underlying plasticity induction and for the development of personalized EEG-triggered stimulation protocols. The project is currently ongoing. The results will be presented at the conference.

The effect of bilateral low-frequency rTMS over dorsolateral prefrontal cortex on serum brain-derived neurotropic factor and serotonin in patients with generalized anxiety disorder

To investigate the effect of bilateral low-frequency repetitive transcranial magnetic stimulation (rTMS) over dorsolateral prefrontal cortex on serum brain-derived neurotropic factor (BDNF) and serotonin (5-HT) in patients with generalized anxiety disorders (GAD). As compared with before treatment, the HARS score in patients markedly decreased after treatment, and the levels of serum BDNF and 5-HT were significantly higher. Pearson correlation analysis revealed that the increase in the level of serum 5-HT was positively associated with the increase of the level of serum BDNF, and the change of anxiety score was negatively associated with the change of the level of serum BDNF and 5-HT. The results suggested that alleviation of GAD by bilateral low-frequency rTMS may be involved in the increase of the level of BDNF and the release of 5-HT in the brain.

Effect of Trans Cranial Magnetic Stimulation in Management of Dysphasia, A Systematic Review

Background: Aphasia is the most disabling functional defect after ischemic stroke. It affects more than a third of all stroke victims. Effective therapeutic strategies are needed to treat aphasic patients. Novel techniques, such as methods of delivering cortical brain stimulation to modulate cortical excitability, such as transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), are just beginning to be explored. The purpose of repetitive transcranial magnetic stimulation (rTMS) application in the neuro-rehabilitation of aphasic patients is to act on specific networks involved in the pathophysiology of language processing and to promote adaptive cortical reorganization after stroke. TMS was shown to have lasting effects on cortical excitability that persisted beyond the actual stimulus delivery. Given the ability of this treatment to modulate cortical activity in a focal way, focus was soon placed on the use of this technique in various neurological and psychiatric diseases such as aphasia. Aim of the work: The aim of this work is to evaluate the effect of Transcranial Magnetic Stimulation as a therapy for dysphasia in order to promote an evidence-based practice. This will be made by conducting a systematic review of literature in this topic area. Materials and Methods: This was a systematic review. Seven electronic databases (Medline, Google scholar, CINHAL, Cochrane Database of Systematic Reviews, The Cochrane Central Register of Controlled Trials, Database of Abstracts of Reviews of Effects and Embase) were searched for articles. Relevant studies were further evaluated and studies that met inclusion criteria were reviewed. Results: The literature search yielded 5097 studies. Twenty-six articles were further evaluated to be included. Eleven studies met all inclusion criteria and were chosen for review. The studies provided moderate to strong evidence that rTMS may be an effective treatment for non-fluent stroke aphasia. We have found significantly higher scores on the language assessment scales of patients after the rTMS treatment than those with sham TMS treatment, in most of the included studies. The studies reviewed here established the beneficial effect of rTMS in multiple language domains. The domain of naming is the most affected, with almost all studies demonstrating improvement in naming after stimulation. Conclusion: The current systematic review suggests that inhibitory low frequency rTMS with 90% resting motor threshold (rMT) targeting pars triangularis of the right inferior frontal gyrus can improve multiple language domains in right-handed post-ischemic stroke patients.

Effect of Trans Cranial Magnetic Stimulation in Management of Dysphasia, A Systematic Review

Background: Aphasia is the most disabling functional defect after ischemic stroke. It affects more than a third of all stroke victims. Effective therapeutic strategies are needed to treat aphasic patients. Novel techniques, such as methods of delivering cortical brain stimulation to modulate cortical excitability, such as transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), are just beginning to be explored. The purpose of repetitive transcranial magnetic stimulation (rTMS) application in the neuro-rehabilitation of aphasic patients is to act on specific networks involved in the pathophysiology of language processing and to promote adaptive cortical reorganization after stroke. TMS was shown to have lasting effects on cortical excitability that persisted beyond the actual stimulus delivery. Given the ability of this treatment to modulate cortical activity in a focal way, focus was soon placed on the use of this technique in various neurological and psychiatric diseases such as aphasia. Aim of the work: The aim of this work is to evaluate the effect of Transcranial Magnetic Stimulation as a therapy for dysphasia in order to promote an evidence-based practice. This will be made by conducting a systematic review of literature in this topic area. Materials and Methods: This was a systematic review. Seven electronic databases (Medline, Google scholar, CINHAL, Cochrane Database of Systematic Reviews, The Cochrane Central Register of Controlled Trials, Database of Abstracts of Reviews of Effects and Embase) were searched for articles. Relevant studies were further evaluated and studies that met inclusion criteria were reviewed. Results: The literature search yielded 5097 studies. Twenty-six articles were further evaluated to be included. Eleven studies met all inclusion criteria and were chosen for review. The studies provided moderate to strong evidence that rTMS may be an effective treatment for non-fluent stroke aphasia. We have found significantly higher scores on the language assessment scales of patients after the rTMS treatment than those with sham TMS treatment, in most of the included studies. The studies reviewed here established the beneficial effect of rTMS in multiple language domains. The domain of naming is the most affected, with almost all studies demonstrating improvement in naming after stimulation. Conclusion: The current systematic review suggests that inhibitory low frequency rTMS with 90% resting motor threshold (rMT) targeting pars triangularis of the right inferior frontal gyrus can improve multiple language domains in right-handed post-ischemic stroke patients.

Six-month effectiveness of low-frequency repetitive transcranial magnetic stimulation and intensive occupational therapy in upper limb hemiparesis after stroke

There has been increasing recognition of combination therapy of low-frequency repetitive transcranial magnetic stimulation (rTMS) and intensive occupational therapy (OT) in upper limb hemiparesis. But few studies have reported on the long-term effect. We report the long-term effect of this therapy in upper limb paralysis in chronic stroke patients. Twenty-two patients with chronic hemiparesis, who received combination therapy of low-frequency rTMS and OT were enrolled (age: 55.4 ± 14.8 years; time after onset: 1522 ± 1332 days). Patients underwent 15 days therapy while Wolf Motor Function Test (WMFT) and Action Research Arm Test (ARAT) were recorded before, after, and 6-month after the therapy. Differences in scores were tested for statistical significance by using ANOVA and Tukey. All patients completed the therapy without any adverse effects. All of the score improved significantly between before and after the therapy (WMFT time: from 722 to 590 s, P < 0.05; WMFT FAS: from 37.7 to 42.5 points, P < 0.05; ARAT: from 15.7 to 20.9 points, P < 0.05). The differences between before and 6-month after the therapy were also significant (WMFT time: from 722 to 553 s, P < 0.05; WMFT FAS: from 37.7 to 42.9 points, P < 0.05; ARAT: from 15.7 to 22.5 points, P < 0.05). But there was no significant difference between after and 6-month after the therapy. A combination therapy of low-frequency rTMS and OT enhances motor recovery of the upper limb paralysis in chronic stroke patients. These results suggest that the effect lasts for 6 months after the therapy. This is an area of ongoing research and further studies are needed.

The Effects of Low Frequency Repetitive Transcranial Magnetic Stimulation on White Matter Structural Connectivity in Children with Cerebral Palsy.

Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive treatment technique for recovery of movement disorders by altering cortical plasticity. In this research, we studied the effects of low-frequency rTMS on white matter (WM) structural connectivity and clinical parameters in children with cerebral palsy (CP).,Four spastic hemiplegic CP children were randomly divided into experimental and control groups. In the experimental group, at first, 1Hz rTMS treatment was performed 4 days/week for 3 weeks on two hemiplegia patients over a contralesional primary motor cortex (M1). Then, 1Hz rTMS treatment was performed 4 days/week for 3 weeks followed by a 30min occupational therapy (OT). In the control group, two CP children received sham rTMS for 3 weeks and then sham rTMS combined with OT for 3 weeks in the same schedule as the experimental group. Evaluations performed using diffusion tensor imaging (DTI), and clinical measurements of gait performance before and after the treatment. Graph theoretical analysis was used to characterize topological changes of structural connectivity. Our findings demonstrate the 1Hz rTMS is effective in improving motor activity in spastic hemiplegic CP children, and is more effective when combined with OT.

Combined transcranial magnetic stimulation in the treatment of chronic tinnitus.

ObjectiveRepetitive transcranial magnetic stimulation (rTMS) is currently being tested for suppressing the symptoms of subjective chronic primary tinnitus, although its effect is controversial. The aim of this randomized double‐blinded controlled trial was to determine the effect of rTMS with unique settings for tinnitus treatment.MethodsFifty‐three adult patients suffering from chronic subjective unilateral or bilateral nonpulsatile primary tinnitus for at least 6 months were randomly assigned to rTMS (group 1, n = 20), sham stimulation (group 2, n = 12), or medicament therapy only (group 3, n = 21). The dorsolateral prefrontal cortex (frequency 25 Hz, 300 pulses, and 80% resting motor threshold [RMT]) on the left side and primary auditory cortex (1 Hz, 1000 pulses, 110% RMT) were stimulated on both sides in patients in group 1 for 5 consecutive days. The Tinnitus Reaction Questionnaire (TRQ), Tinnitus Handicap Questionnaire (THQ), Tinnitus Handicap Inventory (THI), Beck Depression Inventory (BDI), pure‐tone audiometry with Fowler scoring of hearing loss, and tinnitus analysis were used to evaluate tinnitus in all patients. Data were recorded the day the patient was included in the study and at 1‐ and 6‐month follow‐up.ResultsThe study groups were homogenous. No significant effect of rTMS was found at 1 or 6 months based on the BDI, THQ, and TRQ scores or tinnitus masking. There was a significant but clinically irrelevant effect on the THI score after 1 and 6 months.InterpretationNo significant effect of bilateral low‐frequency rTMS of the primary auditory cortex and high‐frequency stimulation of the left dorsolateral prefrontal cortex was demonstrated.

Sleep during low-frequency repetitive transcranial magnetic stimulation is associated with functional improvement in upper limb hemiparesis after stroke

Many studies have reported that repetitive transcranial magnetic stimulation (rTMS) is beneficial for post-stroke patients with upper limb hemiparesis. It was reported that application of rTMS during sleep could possibly strengthen neural plasticity. The purpose of this study was to investigate the relationship between sleep during low-frequency rTMS session and improvement of motor function in affected upper limb in post-stroke patients after inpatient rehabilitation combined with rTMS using the bispectral index (BIS) monitor. During 15-day hospitalization, each patient received rTMS and intensive occupational therapy. Low-frequency rTMS with 1Hz was applied over the contralesional motor cortex. During rTMS session, adhesive sensor was put on each patient's forehead and connected to the BIS monitor. The mean score for the maximum change of BIS values during each rTMS session (ΔBIS) was calculated. We regarded the patients with and over 10 of mean ΔBIS as Asleep group and under 10 as Awake group. Fugl-Meyer assessment (FMA) and Action Research Arm Test (ARAT) were evaluated on admission and discharge. Awake group included six patients and Asleep group included seven patients. There was no significant difference in clinical characteristics and in increase of FMA between two groups. Asleep group was significantly superior to Awake group in the increase of ARAT (p < 0.05). There was a significant correlation between the mean of ΔBIS and increase of ARAT (ρ = 0.78, p = 0.002). Sleep during low-frequency rTMS may contribute to improvement of motor function in the affected upper limb.

Modulation of Cerebellar-Cortical Connections in Multiple System Atrophy Type C by Cerebellar Repetitive Transcranial Magnetic Stimulation

This study aims at modulating the altered cerebellar-cortical interactions in patients with multiple system atrophy-cerebellar subtype (MSA-C) by using cerebellar repetitive transcranial magnetic stimulation (rTMS). We hypothesized that cerebellar modulation by low-frequency rTMS can resolve the abnormal cortical excitability in multiple system atrophy cerebellar subtype. We studied detailed effects of rTMS of the cerebellum on reaction time (RT) and short-latency afferent inhibition (SAI) response in MSA-C group, Alzheimer Disease (AD) group, and a control group of healthy individuals. The RT and SAI responses were measured before and after 1 Hz cerebellar rTMS in all groups. The study was conducted in the neurophysiology laboratory in Hacettepe University Hospital. Our results indicated that motor cortex disinhibition was predominant in patients with AD and MSA-C. In AD and control groups, there were no changes in SAI after rTMS. However, after application of rTMS over the cerebellum in MSA-C patients, the pathological disinhibition and RT results showed an improvement compared to their previous results. Our study highlights that cerebellar rTMS impairs abnormal cerebellar-cortical inhibitory connections in case of MSA-C.

Short Interval Intracortical Inhibition Responses to Low-Frequency Repetitive Transcranial Magnetic Stimulation Under Multiple Interstimulus Intervals and Conditioning Intensities

The extent to which short interval intracortical inhibition (SICI) responds to low-frequency repetitive transcranial magnetic stimulation (rTMS) remains inconclusive with reports of increased, decreased and unchanged response following modulation. The aim of this study was to systematically investigate if the variability of SICI following rTMS is explained by the interstimulus interval (ISI) and/or the conditioning stimulus intensity (CSI). Two experiments with pretesting/posttesting and an rTMS session (1 Hz, 90% RMT, 900 pulses) were done. Experiment I (N = 15): SICI with multiple ISIs (1.0-4.0 msec, 0.2 msec increment). Experiment II (N = 15): SICI with CSIs (50-95% of RMT, 5% increment). In both experiments, the cortical silent period (cSP) was also collected. After low-frequency rTMS, no significant change (p > 0.10) in SICI at any specific ISI or CSI was observed, nor did the optimal ISI or CSI change. However, a significant decrease was observed in SICI responses when assessed under the range of ISIs (p = 0.0001), but not CSIs. cSP inhibition increased significantly (p < 0.0015) for both experiments. The optimal ISI or CSI did not shift or reveal SICI changes after inhibitory rTMS. However, when the whole curve of SICI responses were evaluated from a wide range of ISIs, a decrease in inhibition was found. The contrast between the results of individual ISI tests and the wide range of ISI assessment may be due to higher intersubject variability of SICI and/or sample size, rendering traditional SICI testing methods ineffective for measuring changes in inhibition. Further, it is possible that rTMS modulates GABAA and GABAB mediated inhibitory processes differently, which would explain the conflicting results for SICI and cSP.

Repetitive transcranial magnetic stimulation of the right parietal cortex for comorbid generalized anxiety disorder and insomnia: A randomized, double-blind, sham-controlled pilot study

BackgroundRepetitive transcranial magnetic stimulation (rTMS) has been considered to be a promising technique for the treatment of neuropsychiatric disorders. However, little is known about the effectiveness of rTMS in the treatment of generalized anxiety disorder (GAD). Moreover, treatment data on comorbid GAD and insomnia remain lacking. The aim of this study was to examine the therapeutic effects of 1 Hz rTMS applied over the right parietal lobe on both anxiety and insomnia symptoms in patients with comorbid GAD and insomnia. Methods36 patients were randomized to either sham or active rTMS group (n = 18 each group). The rTMS was administered over the right posterior parietal cortex (P4 electrode site) at a frequency of 1 Hz and an intensity of 90% of the resting motor threshold. ResultsTen days of 1 Hz rTMS to the right parietal lobe significantly improved both anxiety and insomnia symptoms in the active group. Although the anxiety severity was not significantly correlated with insomnia severity at baseline, the improvement in the Hamilton Rating Scale for Anxiety (HRSA) scores were positively correlated with improvement in the Pittsburgh Sleep Quality Index (PSQI) scores. ConclusionsThe present study is the first randomized sham-controlled study to assess the effectiveness of low frequency rTMS on the right parietal lobe in patients with comorbid GAD and insomnia. Our results suggested that 1 Hz low frequency rTMS administered over the parietal cortex is effective for both anxiety and insomnia symptoms in patients with comorbid GAD and insomnia.

Effect of intensive motor training with repetitive transcranial magnetic stimulation on upper limb motor function in chronic post-stroke patients with severe upper limb motor impairment

Background Intensive motor training with low-frequency repetitive transcranial magnetic stimulation (rTMS) has efficacy as a therapeutic method for motor dysfunction of the affected upper limb in patients with mild to moderate stroke. However, it is not clear whether this combination therapy has the same effect in chronic post-stroke patients with severe upper limb motor impairment.Objectives The aim of this study was to test the treatment effects of intensive motor training with low-frequency rTMS in chronic post-stroke patients with severe upper limb motor impairment.Methods A convenience sample of 26 chronic post-stroke patients with severe upper limb motor impairment participated in this study with the non-randomized, non-controlled clinical trial. All subjects were hospitalized to receive intensive motor training with low-frequency rTMS. During 2 weeks in which Sundays were excluded, a total of 24 sessions (2 sessions per day) of the intervention were conducted. The Fugl–Meyer Assessment (FMA) and Wolf Motor Function Test (WMFT) were used to assess motor impairment and function of the affected upper limb, respectively, before and after intervention. Paired t-test was used to analyze the effects of the intervention.Results The FMA total score and WMFT log performance time significantly improved from before to after intervention (FMA: 12.6–18.0; WMFT: 3.6–3.3, p < 0.001).Conclusions The present results suggest that intensive motor training with low-frequency rTMS could improve motor impairment in chronic post-stroke patients with severe upper limb motor impairment and contribute to the expansion of the application range of this combination therapy.

T24. The effects of low-frequency repetitive transcranial magnetic stimulation on the local field potentials of hippocampus in rats

Repeated transcranial magnetic stimulation (rTMS), as a non-invasive brain stimulation technique, has been widely used applied in the field of neurology, psychology, rehabilitation. Previous studies have shown that low frequency rTMS have good anti-epilepsy effects, but its mechanism is not fully understood. We used the multi-channel in vivo recording technique to observe the effects of low frequency rTMS on the local field potential (LFPs) of rats hippocampal, and investigate the electrophysiological mechanism of low frequency rTMS in anti-epilepsy. Sprague-Dawley rats were randomly divided into rTMS group, control group and sham group, respectively variously treating with 500 pulses of 0.5 Hz rTMS for continuous 7 days. After last stimulation, LFPs of hippocampus were measured 20 min under anesthesia, then pilocarpine induced-epileptic seizures and recorded LFPs of hippocampus to 1 h after Status epilepticus (SE). LFPs was respectively partitioned using the common physiological frequency bands: delta (0.5–3.5 Hz), theta (4–7 Hz), gamma (30–80 Hz) and ripple (100–250 Hz), both was estimated with spectrum analysis and power spectral density. The results of spectrum analysis showed that compared with control group and sham group, low-frequency rTMS markedly increased spectrum energy and the power spectral density of delta, theta and gamma-band and significantly decreased the value of ripple oscillation (P < 0.05), while no significant difference between control group and sham group. In addition, low-frequency rTMS decreased the proportion of Racine stage 4–5 seizures, extended the period of latency until seizure onset, and significantly restrained the hippocampal ripple activities after seizures (p < 0.05). These results indicate that rTMS has a modulatory effect on the LFPs of hippocampus. The power of basal delta, theta and gamma-band oscillations in response to Low-frequency rTMS may reduce the excitability of hippocampal in normal rats, and it may be associated with the suppression of the pilocarpine induced-seizure activities.

Platform Session – NIBS: Altered recovery from inhibitory repetitive transcranial magnetic stimulation (rTMS) in subjects with photosensitive epilepsy

Introduction Only few studies have explored the pathophysiology of PSE; some Authors have suggested a defective visual inhibition as a contributing factor to photoparoxysmal response, pointing to an overactive visuomotor connectivity thus inducing abnormal motor responses. In order to investigate functional changes underlying photosensitivity, we studied the response of the visual cortex to low-frequency, inhibitory repetitive transcranial magnetic stimulation (rTMS) in drug-free patients with photosensitive seizures and healthy volunteers. Methods Visual evoked potentials (VEPs) triggered by grating stimuli of different luminance contrasts (K20%, K50% and K90%) were recorded in both hemispheres before and after transient functional inactivation of the occipital cortex of one side via low-frequency rTMS (0.5 Hz, at 120 % of resting motor threshold, for 20’). VEPs were recorded before (T0), immediately after (T1) and 45’ following the completion of rTMS (T2). The display was either centered on the vertical meridian (central stimulation) or positioned in the right hemifield (with its inner edge at a distance of 1 degree from the fixation point). Results Baseline amplitudes of the VEP components (N1 and P1) were enhanced in photosensitive patients. At T1, rTMS produced an inhibitory effect on VEPs amplitudes at all contrasts in the targeted side and a concurrent facilitation of responses in the contralateral hemisphere. Compared with PSE subjects, VEP amplitudes remained persistently dampened in the stimulated hemisphere of controls (Holm–Sidak post hoc method, p Conclusion The rapid recovery of excitability and the persistent transcallosal disinhibition following perturbation of cortical activity may play a role in the pathophysiology of photosensitive epilepsy. Beyond the stereotyped dichotomy between generalized and focal epilepsies, our data seem to indicate PSE as a “system disease”.