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Sample records for repetitive stimulation imaging

  1. Mapping of cortical language function by functional magnetic resonance imaging and repetitive navigated transcranial magnetic stimulation in 40 healthy subjects.

    PubMed

    Sollmann, Nico; Ille, Sebastian; Boeckh-Behrens, Tobias; Ringel, Florian; Meyer, Bernhard; Krieg, Sandro M

    2016-07-01

    Functional magnetic resonance imaging (fMRI) is considered to be the standard method regarding non-invasive language mapping. However, repetitive navigated transcranial magnetic stimulation (rTMS) gains increasing importance with respect to that purpose. However, comparisons between both methods are sparse. We performed fMRI and rTMS language mapping of the left hemisphere in 40 healthy, right-handed subjects in combination with the tasks that are most commonly used in the neurosurgical context (fMRI: word-generation = WGEN task; rTMS: object-naming = ON task). Different rTMS error rate thresholds (ERTs) were calculated, and Cohen's kappa coefficient and the cortical parcellation system (CPS) were used for systematic comparison of the two techniques. Overall, mean kappa coefficients were low, revealing no distinct agreement. We found the highest agreement for both techniques when using the 2-out-of-3 rule (CPS region defined as language positive in terms of rTMS if at least 2 out of 3 stimulations led to a naming error). However, kappa for this threshold was only 0.24 (kappa of <0, 0.01-0.20, 0.21-0.40, 0.41-0.60, 0.61-0.80 and 0.81-0.99 indicate less than chance, slight, fair, moderate, substantial and almost perfect agreement, respectively). Because of the inherent differences in the underlying physiology of fMRI and rTMS, the different tasks used and the impossibility of verifying the results via direct cortical stimulation (DCS) in the population of healthy volunteers, one must exercise caution in drawing conclusions about the relative usefulness of each technique for language mapping. Nevertheless, this study yields valuable insights into these two mapping techniques for the most common language tasks currently used in neurosurgical practice.

  2. Priming Hand Motor Training with Repetitive Stimulation of the Fingertips; Performance Gain and Functional Imaging of Training Effects.

    PubMed

    Lotze, Martin; Ladda, Aija Marie; Roschka, Sybille; Platz, Thomas; Dinse, Hubert R

    Application of repetitive electrical stimulation (rES) of the fingers has been shown to improve tactile perception and sensorimotor performance in healthy individuals. To increase motor performance by priming the effects of active motor training (arm ability training; AAT) using rES. We compared the performance gain for the training increase of the averaged AAT tasks of both hands in two groups of strongly right-handed healthy volunteers. Functional Magnetic Resonance Imaging (fMRI) before and after AAT was assessed using three tasks for each hand separately: finger sequence tapping, visually guided grip force modulation, and writing. Performance during fMRI was controlled for preciseness and frequency. A total of 30 participants underwent a two-week unilateral left hand AAT, 15 participants with 20 minutes of rES priming of all fingertips of the trained hand, and 15 participants without rES priming. rES-primed AAT improved the trained left-hand performance across all training tasks on average by 32.9%, non-primed AAT improved by 29.5%. This gain in AAT performance with rES priming was predominantly driven by an increased finger tapping velocity. Functional imaging showed comparable changes for both training groups over time. Across all participants, improved AAT performance was associated with a higher contralateral primary somatosensory cortex (S1) fMRI activation magnitude during the grip force modulation task. This study highlights the importance of S1 for hand motor training gain. In addition, it suggests the usage of rES of the fingertips for priming active hand motor training. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. 21 CFR 882.5805 - Repetitive transcranial magnetic stimulation system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Repetitive transcranial magnetic stimulation....5805 Repetitive transcranial magnetic stimulation system. (a) Identification. A repetitive transcranial magnetic stimulation system is an external device that delivers transcranial repetitive pulsed...

  4. 21 CFR 882.5805 - Repetitive transcranial magnetic stimulation system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Repetitive transcranial magnetic stimulation....5805 Repetitive transcranial magnetic stimulation system. (a) Identification. A repetitive transcranial magnetic stimulation system is an external device that delivers transcranial repetitive pulsed...

  5. 21 CFR 882.5805 - Repetitive transcranial magnetic stimulation system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Repetitive transcranial magnetic stimulation....5805 Repetitive transcranial magnetic stimulation system. (a) Identification. A repetitive transcranial magnetic stimulation system is an external device that delivers transcranial repetitive pulsed...

  6. Functional cortical reorganization after low-frequency repetitive transcranial magnetic stimulation plus intensive occupational therapy for upper limb hemiparesis: evaluation by functional magnetic resonance imaging in poststroke patients.

    PubMed

    Yamada, Naoki; Kakuda, Wataru; Senoo, Atsushi; Kondo, Takahiro; Mitani, Sugao; Shimizu, Masato; Abo, Masahiro

    2013-08-01

    Low-frequency repetitive transcranial magnetic stimulation of the nonlesional hemisphere combined with occupational therapy significantly improves motor function of the affected upper limb in poststroke hemiparetic patients, but the recovery mechanism remains unclear. To investigate the recovery mechanism using functional magnetic resonance imaging. Forty-seven poststroke hemiparetic patients were hospitalized to receive 12 sessions of 40-min low-frequency repetitive transcranial magnetic stimulation over the nonlesional hemisphere and daily occupational therapy for 15 days. Motor function was evaluated with the Fugl-Meyer Assessment and Wolf Motor Function Test. The functional magnetic resonance imaging with motor tasks was performed at admission and discharge. The laterality index of activated voxel number in Brodmann areas 4 and 6 on functional magnetic resonance imaging was calculated (laterality index range of -1 to +1). Patients were divided into two groups based on functional magnetic resonance imaging findings before the intervention: group 1: patients who showed bilateral activation (n = 27); group 2: patients with unilateral activation (n = 20). Treatment resulted in improvement in Fugl-Meyer Assessment and Wolf Motor Function Test in the two groups (P < 0·01). The treatment also resulted in a significant increase in laterality index in group 1 (P < 0·05), suggesting a shift in activated voxels to the lesional hemisphere. Patients of group 2 showed a significant increase in lesional hemisphere activation (P < 0·05). The results of serial functional magnetic resonance imaging indicated that our proposed treatment can induce functional cortical reorganization, leading to motor functional recovery of the affected upper limb. Especially, it seems that neural activation in the lesional hemisphere plays an important role in such recovery in poststroke hemiparetic patients. © 2013 The Authors. International Journal of Stroke © 2013 World

  7. Neuromodulatory effects of offline low-frequency repetitive transcranial magnetic stimulation of the motor cortex: A functional magnetic resonance imaging study

    PubMed Central

    Min, Yu-Sun; Park, Jang Woo; Jin, Seong Uk; Jang, Kyung Eun; Lee, Byung-Joo; Lee, Hui Joong; Lee, Jongmin; Lee, Yang-Soo; Chang, Yongmin; Jung, Tae-Du

    2016-01-01

    Repetitive transcranial magnetic stimulation (rTMS) of the primary motor cortex (M1) can modulate cortical excitability and is thought to influence activity in other brain areas. In this study, we investigated the anatomical and functional effects of rTMS of M1 and the time course of after-effects from a 1-Hz subthreshold rTMS to M1. Using an “offline” functional magnetic resonance imaging (fMRI)-rTMS paradigm, neural activation was mapped during simple finger movements after 1-Hz rTMS over the left M1 in a within-subjects repeated measurement design, including rTMS and sham stimulation. A significant decrease in the blood oxygen level dependent (BOLD) signal due to right hand motor activity during a simple finger-tapping task was observed in areas remote to the stimulated motor cortex after rTMS stimulation. This decrease in BOLD signal suggests that low frequency subthreshold rTMS may be sufficiently strong to elicit inhibitory modulation of remote brain regions. In addition, the time course patterns of BOLD activity showed this inhibitory modulation was maximal approximately 20 minutes after rTMS stimulation. PMID:27786301

  8. Clinical application of repetitive transcranial magnetic stimulation in stroke rehabilitation☆

    PubMed Central

    Shin, Joonho; Yang, EunJoo; Cho, KyeHee; Barcenas, Carmelo L; Kim, Woo Jin; Min, Yusun; Paik, Nam-Jong

    2012-01-01

    Proper stimulation to affected cerebral hemisphere would promote the functional recovery of patients with stroke. Effects of repetitive transcranial magnetic stimulation on cortical excitability can be can be altered by the stimulation frequency, intensity and duration. There has been no consistent recognition regarding the best stimulation frequency and intensity. This study reviews the intervention effects of repetitive transcranial stimulation on motor impairment, dysphagia, visuospatial neglect and aphasia, and summarizes the stimulation frequency, intensity and area for repetitive transcranial magnetic stimulation to yield the best therapeutic effects. PMID:25745455

  9. Neural dynamics during repetitive visual stimulation

    NASA Astrophysics Data System (ADS)

    Tsoneva, Tsvetomira; Garcia-Molina, Gary; Desain, Peter

    2015-12-01

    Objective. Steady-state visual evoked potentials (SSVEPs), the brain responses to repetitive visual stimulation (RVS), are widely utilized in neuroscience. Their high signal-to-noise ratio and ability to entrain oscillatory brain activity are beneficial for their applications in brain-computer interfaces, investigation of neural processes underlying brain rhythmic activity (steady-state topography) and probing the causal role of brain rhythms in cognition and emotion. This paper aims at analyzing the space and time EEG dynamics in response to RVS at the frequency of stimulation and ongoing rhythms in the delta, theta, alpha, beta, and gamma bands. Approach.We used electroencephalography (EEG) to study the oscillatory brain dynamics during RVS at 10 frequencies in the gamma band (40-60 Hz). We collected an extensive EEG data set from 32 participants and analyzed the RVS evoked and induced responses in the time-frequency domain. Main results. Stable SSVEP over parieto-occipital sites was observed at each of the fundamental frequencies and their harmonics and sub-harmonics. Both the strength and the spatial propagation of the SSVEP response seem sensitive to stimulus frequency. The SSVEP was more localized around the parieto-occipital sites for higher frequencies (>54 Hz) and spread to fronto-central locations for lower frequencies. We observed a strong negative correlation between stimulation frequency and relative power change at that frequency, the first harmonic and the sub-harmonic components over occipital sites. Interestingly, over parietal sites for sub-harmonics a positive correlation of relative power change and stimulation frequency was found. A number of distinct patterns in delta (1-4 Hz), theta (4-8 Hz), alpha (8-12 Hz) and beta (15-30 Hz) bands were also observed. The transient response, from 0 to about 300 ms after stimulation onset, was accompanied by increase in delta and theta power over fronto-central and occipital sites, which returned to baseline

  10. Repetitive transcranial magnetic stimulation and drug addiction.

    PubMed

    Barr, Mera S; Farzan, Faranak; Wing, Victoria C; George, Tony P; Fitzgerald, Paul B; Daskalakis, Zafiris J

    2011-10-01

    Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive brain stimulation technique that is now being tested for its ability to treat addiction. This review discusses current research approaches and results of studies which measured the therapeutic use of rTMS to treat tobacco, alcohol and illicit drug addiction. The research in this area is limited and therefore all studies evaluating the therapeutic use of rTMS in tobacco, alcohol or illicit drug addiction were retained including case studies through NCBI PubMed ( http://www.ncbi.nlm.nih.gov ) and manual searches. A total of eight studies were identified that examined the ability of rTMS to treat tobacco, alcohol and cocaine addiction. The results of this review indicate that rTMS is effective in reducing the level of cravings for smoking, alcohol, and cocaine when applied at high frequencies to the dorsolateral prefrontal cortex (DLPFC). Furthermore, these studies suggest that repeated sessions of high frequency rTMS over the DLPFC may be most effective in reducing the level of smoking and alcohol consumption. Although work in this area is limited, this review indicates that rTMS is a promising modality for treating drug addiction.

  11. [Rehabilitation Using Repetitive Transcranial Magnetic Stimulation].

    PubMed

    Takeuchi, Naoyuki; Izumi, Shin-Ichi

    2017-03-01

    Various novel stroke rehabilitative methods have been developed based on findings in basic science and clinical research. Recently, many reports have shown that repetitive transcranial magnetic stimulation (rTMS) improves function in stroke patients by altering the excitability of the human cortex. The interhemispheric competition model proposes that deficits in stroke patients are due to reduced output from the affected hemisphere and excessive interhemispheric inhibition from the unaffected hemisphere to the affected hemisphere. The interhemispheric competition model indicates that improvement in deficits can be achieved either by increasing the excitability of the affected hemisphere using excitatory rTMS or by decreasing the excitability of the unaffected hemisphere using inhibitory rTMS. Recovery after stroke is related to neural plasticity, which involves developing new neural connections, acquiring new functions, and compensating for impairments. Artificially modulating the neural network by rTMS may induce a more suitable environment for use-dependent plasticity and also may interfere with maladaptive neural activation, which weakens function and limits recovery. There is potential, therefore, for rTMS to be used as an adjuvant therapy for developed neurorehabilitation techniques in stroke patients.

  12. [Repetitive transcranial magnetic stimulation: A potential therapy for cognitive disorders?

    PubMed

    Nouhaud, C; Sherrard, R M; Belmin, J

    2017-03-01

    Considering the limited effectiveness of drugs treatments in cognitive disorders, the emergence of noninvasive techniques to modify brain function is very interesting. Among these techniques, repetitive transcranial magnetic stimulation (rTMS) can modulate cortical excitability and have potential therapeutic effects on cognition and behaviour. These effects are due to physiological modifications in the stimulated cortical tissue and their associated circuits, which depend on the parameters of stimulation. The objective of this article is to specify current knowledge and efficacy of rTMS in cognitive disorders. Previous studies found very encouraging results with significant improvement of higher brain functions. Nevertheless, these few studies have limits: a few patients were enrolled, the lack of control of the mechanisms of action by brain imaging, insufficiently formalized technique and variability of cognitive tests. It is therefore necessary to perform more studies, which identify statistical significant improvement and to specify underlying mechanisms of action and the parameters of use of the rTMS to offer rTMS as a routine therapy for cognitive dysfunction.

  13. Modulation of sensorimotor cortex by repetitive peripheral magnetic stimulation

    PubMed Central

    Gallasch, Eugen; Christova, Monica; Kunz, Alexander; Rafolt, Dietmar; Golaszewski, Stefan

    2015-01-01

    This study examines with transcranial magnetic stimulation (TMS) and with functional magnetic resonance imaging (fMRI) whether 20 min of repetitive peripheral magnetic stimulation (rPMS) has a facilitating effect on associated motor controlling regions. Trains of rPMS with a stimulus intensity of 150% of the motor threshold (MT) were applied over right hand flexor muscles of healthy volunteers. First, with TMS, 10 vs. 25 Hz rPMS was examined and compared to a control group. Single and paired pulse motor evoked potentials (MEPs) from flexor carpi radialis (FCR) and extensor carpi radialis (ECR) muscles were recorded at baseline (T0), post rPMS (T1), 30 min post (T2), 1 h post (T3) and 2 h post rPMS (T4). Then, with fMRI, 25 Hz rPMS was compared to sham stimulation by utilizing a finger tapping activation paradigm. Changes in bloodoxygen level dependent (BOLD) contrast were examined at baseline (PRE), post rPMS (POST1) and 1 h post rPMS (POST2). With TMS facilitation was observed in the target muscle (FCR) following 25 Hz rPMS: MEP recruitment curves (RCs) were increased at T1, T2 and T3, and intracortical facilitation (ICF) was increased at T1 and T2. No effects were observed following 10 Hz rPMS. With fMRI the BOLD contrast at the left sensorimotor area was increased at POST1. Compared to inductions protocols based on transcutaneous electrical stimulation and mechanical stimulation, the rPMS induced effects appeared shorter lasting. PMID:26236220

  14. Repetitive electric brain stimulation reduces food intake in humans.

    PubMed

    Jauch-Chara, Kamila; Kistenmacher, Alina; Herzog, Nina; Schwarz, Marianka; Schweiger, Ulrich; Oltmanns, Kerstin M

    2014-10-01

    The dorsolateral prefrontal cortex (DLPFC) plays an important role in appetite and food intake regulation. Because previous data revealed that transcranial direct current stimulation (tDCS) of the DLPFC reduces food cravings, we hypothesized that repetitive electric stimulation of the right DLPFC would lower food intake behavior in humans. In a single-blind, code-based, placebo-controlled, counterbalanced, randomized crossover experiment, 14 healthy young men with body mass index (in kg/m(2)) from 20 to 25 were examined during 8 d of daily tDCS or a sham stimulation. After tDCS or sham stimulation on the first and the last day of both experimental conditions, participants consumed food ad libitum from a standardized test buffet. One week of daily anodal tDCS reduced overall caloric intake by 14% in comparison with sham stimulation. Moreover, repetitive tDCS diminished self-reported appetite scores. Our study implies that the application of anodal direct currents to the right DLPFC represents a promising option for reducing both caloric intake and appetite in humans. This trial was registered at the German Clinical Trials Register (www.germanctr.de) as DRKS00005811. © 2014 American Society for Nutrition.

  15. Repetitive Transcranial Magnetic Stimulation Activates Specific Regions in Rat Brain

    NASA Astrophysics Data System (ADS)

    Ji, Ru-Rong; Schlaepfer, Thomas E.; Aizenman, Carlos D.; Epstein, Charles M.; Qiu, Dike; Huang, Justin C.; Rupp, Fabio

    1998-12-01

    Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive technique to induce electric currents in the brain. Although rTMS is being evaluated as a possible alternative to electroconvulsive therapy for the treatment of refractory depression, little is known about the pattern of activation induced in the brain by rTMS. We have compared immediate early gene expression in rat brain after rTMS and electroconvulsive stimulation, a well-established animal model for electroconvulsive therapy. Our result shows that rTMS applied in conditions effective in animal models of depression induces different patterns of immediate-early gene expression than does electroconvulsive stimulation. In particular, rTMS evokes strong neural responses in the paraventricular nucleus of the thalamus (PVT) and in other regions involved in the regulation of circadian rhythms. The response in PVT is independent of the orientation of the stimulation probe relative to the head. Part of this response is likely because of direct activation, as repetitive magnetic stimulation also activates PVT neurons in brain slices.

  16. Repetitive magnetic stimulation induces plasticity of inhibitory synapses

    PubMed Central

    Lenz, Maximilian; Galanis, Christos; Müller-Dahlhaus, Florian; Opitz, Alexander; Wierenga, Corette J.; Szabó, Gábor; Ziemann, Ulf; Deller, Thomas; Funke, Klaus; Vlachos, Andreas

    2016-01-01

    Repetitive transcranial magnetic stimulation (rTMS) is used as a therapeutic tool in neurology and psychiatry. While repetitive magnetic stimulation (rMS) has been shown to induce plasticity of excitatory synapses, it is unclear whether rMS can also modify structural and functional properties of inhibitory inputs. Here we employed 10-Hz rMS of entorhinohippocampal slice cultures to study plasticity of inhibitory neurotransmission on CA1 pyramidal neurons. Our experiments reveal a rMS-induced reduction in GABAergic synaptic strength (2–4 h after stimulation), which is Ca2+-dependent and accompanied by the remodelling of postsynaptic gephyrin scaffolds. Furthermore, we present evidence that 10-Hz rMS predominantly acts on dendritic, but not somatic inhibition. Consistent with this finding, a reduction in clustered gephyrin is detected in CA1 stratum radiatum of rTMS-treated anaesthetized mice. These results disclose that rTMS induces coordinated Ca2+-dependent structural and functional changes of specific inhibitory postsynapses on principal neurons. PMID:26743822

  17. Repetitive Transcranial Magnetic Stimulation Improves Handwriting in Parkinson's Disease

    PubMed Central

    Randhawa, Bubblepreet K.; Farley, Becky G.; Boyd, Lara A.

    2013-01-01

    Background. Parkinson disease (PD) is characterized by hypometric movements resulting from loss of dopaminergic neurons in the substantia nigra. PD leads to decreased activation of the supplementary motor area (SMA); the net result of these changes is a poverty of movement. The present study determined the impact of 5 Hz repetitive transcranial magnetic stimulation (rTMS) over the SMA on a fine motor movement, handwriting (writing cursive “l”s), and on cortical excitability, in individuals with PD. Methods. In a cross-over design, ten individuals with PD were randomized to receive either 5 Hz or control stimulation over the SMA. Immediately following brain stimulation right handed writing was assessed. Results. 5 Hz stimulation increased vertical size of handwriting and diminished axial pressure. In addition, 5 Hz rTMS significantly decreased the threshold for excitability in the primary motor cortex. Conclusions. These data suggest that in the short term 5 Hz rTMS benefits functional fine motor task performance, perhaps by altering cortical excitability across a network of brain regions. Further, these data may provide the foundation for a larger investigation of the effects of noninvasive brain stimulation over the SMA in individuals with PD. PMID:23841021

  18. Outcomes in spasticity after repetitive transcranial magnetic and transcranial direct current stimulations

    PubMed Central

    Gunduz, Aysegul; Kumru, Hatice; Pascual-Leone, Alvaro

    2014-01-01

    Non-invasive brain stimulations mainly consist of repetitive transcranial magnetic stimulation and transcranial direct current stimulation. Repetitive transcranial magnetic stimulation exhibits satisfactory outcomes in improving multiple sclerosis, stroke, spinal cord injury and cerebral palsy-induced spasticity. By contrast, transcranial direct current stimulation has only been studied in post-stroke spasticity. To better validate the efficacy of non-invasive brain stimulations in improving the spasticity post-stroke, more prospective cohort studies involving large sample sizes are needed. PMID:25206878

  19. Rehabilitation interventions for chronic motor deficits with repetitive transcranial magnetic stimulation.

    PubMed

    Paquette, C; Thiel, A

    2012-12-01

    Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive electrophysiological method to modulate cortical excitability. As such, rTMS can be used in conjunction with conventional physiotherapy or occupational therapy to facilitate rehabilitation of motor function in patients with focal brain lesions. This review summarizes the rationale for using rTMS in the rehabilitation of motor deficits as derived from imaging and electrophysiological studies of the human motor system. rTMS methodology and its various stimulation modalities are introduced and current evidence for rTMS as supportive therapy for the rehabilitation of chronic motor deficits is discussed.

  20. [Therapeutic application of repetitive transcranial magnetic stimulation for major depression].

    PubMed

    Nakamura, Motoaki

    2012-01-01

    It has been reported that approximately one third of patients with major depression are medication-resistant. In spite of partial responsiveness to antidepressants, most of the medication-resistant patients remain incompletely remitted without successful social reintegration. Symptom severity could be mild to moderate for many of them due to the incomplete remission, and, thus, electroconvulsive therapy is not applicable for them. However, they usually feel some difficulty performing cognitive behavioral therapy or social rehabilitation training due to residual symptoms such as thought inhibition and hypobulia. Under such conditions, those patients are longing for treatment options complementary to antidepressants, for less painful social reintegration. In October 2008, the Food and Drug Administration (FDA) of the United States finally approved repetitive Transcranial Magnetic Stimulation (rTMS) for medication-resistant patients with major depression. The main reason for the FDA approval was that rTMS had shown similar effectiveness (effect size around 0.39 in a recent meta-analysis) to antidepressants for medication-resistant patients without serious adverse effects. TMS is a brain stimulation methodology employing magnetic energy which can penetrate the skull bone without energy decay, and, thus, eddy currents induced by TMS can stimulate cerebral cortices effectively and locally. When TMS is repetitively delivered over several hundreds of pulses within a session, stimulation effects can be observed beyond the stimulation period as aftereffects. Moreover, when a daily rTMS session is repeated over several weeks, rTMS could have antidepressant effects. Clinical trials of rTMS for depression have employed two kinds of rTMS protocol of high-frequency (facilitatory) rTMS over the left Dorsolateral Prefrontal Cortex (DLPFC) and low-frequency (inhibitory) rTMS over the right DLPFC. Although the antidepressant action of rTMS over DLPFC has not been fully elucidated

  1. Use of Repetitive Transcranial Magnetic Stimulation for Treatment in Psychiatry

    PubMed Central

    2013-01-01

    The potential of noninvasive neurostimulation by repetitive transcranial magnetic stimulation (rTMS) for improving psychiatric disorders has been studied increasingly over the past two decades. This is especially the case for major depression and for auditory-verbal hallucinations in schizophrenia. The present review briefly describes the background of this novel treatment modality and summarizes evidence from clinical trials into the efficacy of rTMS for depression and hallucinations. Evidence for efficacy in depression is stronger than for hallucinations, although a number of studies have reported clinically relevant improvements for hallucinations too. Different stimulation parameters (frequency, duration, location of stimulation) are discussed. There is a paucity of research into other psychiatric disorders, but initial evidence suggests that rTMS may also hold promise for the treatment of negative symptoms in schizophrenia, obsessive compulsive disorder and post-traumatic stress disorder. It can be concluded that rTMS induces alterations in neural networks relevant for psychiatric disorders and that more research is needed to elucidate efficacy and underlying mechanisms of action. PMID:24023548

  2. Use of repetitive transcranial magnetic stimulation for treatment in psychiatry.

    PubMed

    Aleman, André

    2013-08-01

    The potential of noninvasive neurostimulation by repetitive transcranial magnetic stimulation (rTMS) for improving psychiatric disorders has been studied increasingly over the past two decades. This is especially the case for major depression and for auditory-verbal hallucinations in schizophrenia. The present review briefly describes the background of this novel treatment modality and summarizes evidence from clinical trials into the efficacy of rTMS for depression and hallucinations. Evidence for efficacy in depression is stronger than for hallucinations, although a number of studies have reported clinically relevant improvements for hallucinations too. Different stimulation parameters (frequency, duration, location of stimulation) are discussed. There is a paucity of research into other psychiatric disorders, but initial evidence suggests that rTMS may also hold promise for the treatment of negative symptoms in schizophrenia, obsessive compulsive disorder and post-traumatic stress disorder. It can be concluded that rTMS induces alterations in neural networks relevant for psychiatric disorders and that more research is needed to elucidate efficacy and underlying mechanisms of action.

  3. Repetitive visual stimulation enhances recovery from severe amblyopia

    PubMed Central

    Montey, Karen L.; Eaton, Nicolette C.; Quinlan, Elizabeth M.

    2013-01-01

    Severe amblyopia, characterized by a significant reduction in visual acuity through the affected eye, is highly resistant to reversal in adulthood. We have previously shown that synaptic plasticity can be reactivated in the adult rat visual cortex by dark exposure, and the reactivated plasticity can be harnessed to promote the recovery from severe amblyopia. Here we show that deprived-eye visually evoked responses are rapidly strengthened in dark-exposed amblyopes by passive viewing of repetitive visual stimuli. Surprisingly, passive visual stimulation rapidly enhanced visually evoked responses to novel stimuli and enhanced the recovery from severe amblyopia driven by performance of active visual discriminations. Thus a series of simple, noninvasive manipulations of visual experience can be used in combination to significantly guide the recovery of visual response strength, selectivity, and spatial acuity in adult amblyopes. PMID:23685763

  4. Repetitive transcranial magnetic stimulation for hallucination in schizophrenia spectrum disorders: A meta-analysis

    PubMed Central

    Zhang, Yingli; Liang, Wei; Yang, Shichang; Dai, Ping; Shen, Lijuan; Wang, Changhong

    2013-01-01

    Objective: This study assessed the efficacy and tolerability of repetitive transcranial magnetic stimulation for treatment of auditory hallucination of patients with schizophrenia spectrum disorders. Data Sources: Online literature retrieval was conducted using PubMed, ISI Web of Science, EMBASE, Medline and Cochrane Central Register of Controlled Trials databases from January 1985 to May 2012. Key words were “transcranial magnetic stimulation”, “TMS”, “repetitive transcranial magnetic stimulation”, and “hallucination”. Study Selection: Selected studies were randomized controlled trials assessing therapeutic efficacy of repetitive transcranial magnetic stimulation for hallucination in patients with schizophrenia spectrum disorders. Experimental intervention was low-frequency repetitive transcranial magnetic stimulation in left temporoparietal cortex for treatment of auditory hallucination in schizophrenia spectrum disorders. Control groups received sham stimulation. Main Outcome Measures: The primary outcome was total scores of Auditory Hallucinations Rating Scale, Auditory Hallucination Subscale of Psychotic Symptom Rating Scale, Positive and Negative Symptom Scale-Auditory Hallucination item, and Hallucination Change Scale. Secondary outcomes included response rate, global mental state, adverse effects and cognitive function. Results: Seventeen studies addressing repetitive transcranial magnetic stimulation for treatment of schizophrenia spectrum disorders were screened, with controls receiving sham stimulation. All data were completely effective, involving 398 patients. Overall mean weighted effect size for repetitive transcranial magnetic stimulation versus sham stimulation was statistically significant (MD = –0.42, 95%CI: –0.64 to –0.20, P = 0.000 2). Patients receiving repetitive transcranial magnetic stimulation responded more frequently than sham stimulation (OR = 2.94, 95%CI: 1.39 to 6.24, P = 0.005). No significant differences were

  5. Stimulated Raman photoacoustic imaging

    PubMed Central

    Yakovlev, Vladislav V.; Zhang, Hao F.; Noojin, Gary D.; Denton, Michael L.; Thomas, Robert J.; Scully, Marlan O.

    2010-01-01

    Achieving label-free, molecular-specific imaging with high spatial resolution in deep tissue is often considered the grand challenge of optical imaging. To accomplish this goal, significant optical scattering in tissues has to be overcome while achieving molecular specificity without resorting to extrinsic labeling. We demonstrate the feasibility of developing such an optical imaging modality by combining the molecularly specific stimulated Raman excitation with the photoacoustic detection. By employing two ultrashort excitation laser pulses, separated in frequency by the vibrational frequency of a targeted molecule, only the specific vibrational level of the target molecules in the illuminated tissue volume is excited. This targeted optical absorption generates ultrasonic waves (referred to as stimulated Raman photoacoustic waves) which are detected using a traditional ultrasonic transducer to form an image following the design of the established photoacoustic microscopy. PMID:21059930

  6. Hemicerebellectomy blocks the enhancement of cortical motor output associated with repetitive somatosensory stimulation in the rat

    PubMed Central

    Taib Nordeyn, Oulad Ben; Mario, Manto; Massimo, Pandolfo; Jacques, Brotchi

    2005-01-01

    Repetitive peripheral stimulation is associated with an enhancement of the intensity of corticomotor responses. We analysed the effects of hemicerebellectomy on the modulation of cortical motor output associated with repetitive electrical stimulation of the sciatic nerve in the rat. Hemicerebellectomy blocked the enhancement of the corticomotor response. The cerebellum is a key player in this form of short-term plasticity. PMID:15946961

  7. Role of repetitive transcranial magnetic stimulation in stroke rehabilitation.

    PubMed

    Pinter, Michaela M; Brainin, Michael

    2013-01-01

    In recent years, efforts have focused on investigating the neurophysiological changes that occur in the brain after stroke, and on developing novel strategies such as additional brain stimulation to enhance sensorimotor and cognitive recovery. In the 1990s, repetitive transcranial magnetic stimulation (rTMS) was introduced as a therapeutic tool for improving the efficacy of rehabilitation for recovery after stroke. It is evident that disturbances of interhemispheric processes after stroke result in a pathological hyperactivity of the intact hemisphere. The rationale of using rTMS as a complementary therapy is mainly to decrease the cortical excitability in regions that are presumed to hinder optimal recovery by low-frequency rTMS delivered to the unaffected hemisphere, while high-frequency rTMS delivered to the affected hemisphere facilitates cortical excitability. However, the exact mechanisms of how rTMS works are still under investigation. There is a growing body of research in stroke patients investigating the effect of rTMS on facilitating recovery by modifying cortical and subcortical networks. Clinical trials applying rTMS already yielded promising results in improving recovery of sensorimotor and cognitive functions. Altogether, in combination with conventional therapeutic approaches, rTMS has a potential to become a complementary strategy to enhance stroke recovery by modulating the excitability of targeted brain areas. In future studies, emphasis should be placed on selecting patient populations to determine whether treatment response depends on age, lesion acuteness, or stroke severity. Furthermore, it is important to identify parameters optimizing the beneficial effects of rTMS on stroke recovery, and to monitor their long-term effects.

  8. Repetitive transcranial magnetic stimulator with controllable pulse parameters.

    PubMed

    Peterchev, Angel V; Murphy, David L; Lisanby, Sarah H

    2011-06-01

    The characteristics of transcranial magnetic stimulation (TMS) pulses influence the physiological effect of TMS. However, available TMS devices allow very limited adjustment of the pulse parameters. We describe a novel TMS device that uses a circuit topology incorporating two energy storage capacitors and two insulated-gate bipolar transistor (IGBT) modules to generate near-rectangular electric field pulses with adjustable number, polarity, duration, and amplitude of the pulse phases. This controllable pulse parameter TMS (cTMS) device can induce electric field pulses with phase widths of 10-310 µs and positive/negative phase amplitude ratio of 1-56. Compared to conventional monophasic and biphasic TMS, cTMS reduces energy dissipation up to 82% and 57% and decreases coil heating up to 33% and 41%, respectively. We demonstrate repetitive TMS trains of 3000 pulses at frequencies up to 50 Hz with electric field pulse amplitude and width variability less than the measurement resolution (1.7% and 1%, respectively). Offering flexible pulse parameter adjustment and reduced power consumption and coil heating, cTMS enhances existing TMS paradigms, enables novel research applications and could lead to clinical applications with potentially enhanced potency.

  9. Repetitive Transcranial Magnetic Stimulator with Controllable Pulse Parameters

    PubMed Central

    Peterchev, Angel V; Murphy, David L; Lisanby, Sarah H

    2013-01-01

    The characteristics of transcranial magnetic stimulation (TMS) pulses influence the physiological effect of TMS. However, available TMS devices allow very limited adjustment of the pulse parameters. We describe a novel TMS device that uses a circuit topology incorporating two energy storage capacitors and two insulated-gate bipolar transistor (IGBT) modules to generate near-rectangular electric field pulses with adjustable number, polarity, duration, and amplitude of the pulse phases. This controllable pulse parameter TMS (cTMS) device can induce electric field pulses with phase widths of 10–310 μs and positive/negative phase amplitude ratio of 1–56. Compared to conventional monophasic and biphasic TMS, cTMS reduces energy dissipation by up to 82% and 57%, and decreases coil heating by up to 33% and 41%, respectively. We demonstrate repetitive TMS trains of 3,000 pulses at frequencies up to 50 Hz with electric field pulse amplitude and width variability less than the measurement resolution (1.7% and 1%, respectively). Offering flexible pulse parameter adjustment and reduced power consumption and coil heating, cTMS enhances existing TMS paradigms, enables novel research applications, and could lead to clinical applications with potentially enhanced potency. PMID:21540487

  10. Repetitive transcranial magnetic stimulator with controllable pulse parameters

    NASA Astrophysics Data System (ADS)

    Peterchev, Angel V.; Murphy, David L.; Lisanby, Sarah H.

    2011-06-01

    The characteristics of transcranial magnetic stimulation (TMS) pulses influence the physiological effect of TMS. However, available TMS devices allow very limited adjustment of the pulse parameters. We describe a novel TMS device that uses a circuit topology incorporating two energy storage capacitors and two insulated-gate bipolar transistor (IGBT) modules to generate near-rectangular electric field pulses with adjustable number, polarity, duration, and amplitude of the pulse phases. This controllable pulse parameter TMS (cTMS) device can induce electric field pulses with phase widths of 10-310 µs and positive/negative phase amplitude ratio of 1-56. Compared to conventional monophasic and biphasic TMS, cTMS reduces energy dissipation up to 82% and 57% and decreases coil heating up to 33% and 41%, respectively. We demonstrate repetitive TMS trains of 3000 pulses at frequencies up to 50 Hz with electric field pulse amplitude and width variability less than the measurement resolution (1.7% and 1%, respectively). Offering flexible pulse parameter adjustment and reduced power consumption and coil heating, cTMS enhances existing TMS paradigms, enables novel research applications and could lead to clinical applications with potentially enhanced potency.

  11. Treating anxious depression using repetitive transcranial magnetic stimulation.

    PubMed

    Diefenbach, Gretchen J; Bragdon, Laura; Goethe, John W

    2013-10-01

    A subset of patients given a clinical diagnosis of major depressive disorder (MDD) are described as having "anxious depression," a presentation that, in some studies, has been an indicator of poor response to pharmacotherapy. The aim of this study was to determine if anxious depression is associated with attenuated response to repetitive transcranial magnetic stimulation (rTMS), an FDA-approved treatment for MDD. Participants were 32 adult outpatients with treatment resistant MDD who were referred for rTMS. The Hamilton Rating Scale for Depression (HAMD) was administered to assess treatment response, and anxious depression was defined as a score of seven or above on the anxiety/somatization factor of the HAMD. A quarter of the sample met the anxious depression criterion at pretreatment. Both depression (total score) and anxiety symptoms improved from pre- to post-treatment with moderate to large treatment effects. Patients with and without anxious depression demonstrated similar rates of improvement in depression. Patients with versus without anxious depression demonstrated larger improvements in anxiety. The sample size was small, and assessments did not include structured diagnostic interview or independent measures of anxiety symptoms. For the sample as a whole, there were significant improvements in both depression and anxiety. Anxious depression was not associated with attenuated treatment response to rTMS. © 2013 Elsevier B.V. All rights reserved.

  12. The interaction between duration, velocity and repetitive auditory stimulation.

    PubMed

    Makin, Alexis D J; Poliakoff, Ellen; Dillon, Joe; Perrin, Aimee; Mullet, Thomas; Jones, Luke A

    2012-03-01

    Repetitive auditory stimulation (with click trains) and visual velocity signals both have intriguing effects on the subjective passage of time. Previous studies have established that prior presentation of auditory clicks increases the subjective duration of subsequent sensory input, and that faster moving stimuli are also judged to have been presented for longer (the time dilation effect). However, the effect of clicks on velocity estimation is unknown, and the nature of the time dilation effect remains ambiguous. Here were present a series of five experiments to explore these phenomena in more detail. Participants viewed a rightward moving grating which traveled at velocities ranging from 5 to 15°/s and which lasted for durations of 500 to 1500 ms. Gratings were preceded by clicks, silence or white noise. It was found that both clicks and higher velocities increased subjective duration. It was also found that the time dilation effect was a constant proportion of stimulus duration. This implies that faster velocity increases the rate of the pacemaker component of the internal clock. Conversely, clicks increased subjective velocity, but the magnitude of this effect was not proportional to actual velocity. Through considerations of these results, we conclude that clicks independently affect velocity and duration representations.

  13. Repetitive Transcranial Magnetic Stimulation of the Primary Somatosensory Cortex Modulates Perception of the Tendon Vibration Illusion.

    PubMed

    Huh, D C; Lee, J M; Oh, S M; Lee, J-H; Van Donkelaar, P; Lee, D H

    2016-10-01

    The effect of repetitive transcranial magnetic stimulation on kinesthetic perception, when applied to the somatosensory cortex, was examined. Further, the facilitatory and inhibitory effects of repetitive transcranial magnetic stimulation using different stimulation frequencies were tested. Six female (M age = 32.0 years, SD = 6.7) and nine male (M age = 32.9 years, SD = 6.6) participants were asked to perceive the tendon vibration illusion of the left wrist joint and to replicate the illusion with their right hand. When comparing changes in the corresponding movement amplitude and velocity after three different repetitive transcranial magnetic stimulation protocols (sham, 1 Hz inhibitory, and 5 Hz facilitatory repetitive transcranial magnetic stimulation), the movement amplitude was found to decrease with the inhibitory repetitive transcranial magnetic stimulation, while the movement velocity respectively increased and decreased with the facilitatory and inhibitory repetitive transcranial magnetic stimulation. These results confirmed the modulating effects of repetitive transcranial magnetic stimulation on kinesthetic perception in a single experimental paradigm.

  14. [Repetitive transcranial magnetic stimulation in depression; stimulation of the brain in order to cure the psyche].

    PubMed

    Helmich, R C; Snijders, A H; Verkes, R J; Bloem, B R

    2004-02-28

    Transcranial magnetic stimulation (TMS) is a non-invasive approach to briefly stimulate or inhibit cortical brain areas. A novel approach entails the delivery of repetitive TMS pulses (rTMS) at a fixed frequency. In rTMS cortical activity is altered beyond the period of actual stimulation. The changes occur locally as well as at a distance in functionally connected brain areas. These features render rTMS a suitable tool to study normal brain functions and the pathophysiology of brain diseases. Furthermore, it is expected that rTMS could be used as a novel therapy for neurological or psychiatric diseases characterised by abnormal cortical activation. This possibility has been studied mostly in patients suffering from depression, where rTMS has been used to restore normal activity in the hypoactive prefrontal cortex. Despite statistically significant therapeutic effects in small sized trials, the clinical implications are still limited.

  15. Transient tinnitus suppression induced by repetitive transcranial magnetic stimulation and transcranial direct current stimulation.

    PubMed

    Fregni, F; Marcondes, R; Boggio, P S; Marcolin, M A; Rigonatti, S P; Sanchez, T G; Nitsche, M A; Pascual-Leone, A

    2006-09-01

    Modulation of activity in the left temporoparietal area (LTA) by 10 Hz repetitive transcranial magnetic stimulation (rTMS) results in a transient reduction of tinnitus. We aimed to replicate these results and test whether transcranial direct current stimulation (tDCS) of LTA could yield similar effect. Patients with tinnitus underwent six different types of stimulation in a random order: 10-Hz rTMS of LTA, 10-Hz rTMS of mesial parietal cortex, sham rTMS, anodal tDCS of LTA, cathodal tDCS of LTA and sham tDCS. A non-parametric analysis of variance showed a significant main effect of type of stimulation (P = 0.002) and post hoc tests showed that 10-Hz rTMS and anodal tDCS of LTA resulted in a significant reduction of tinnitus. These effects were short lasting. These results replicate the findings of the previous study and, in addition, show preliminary evidence that anodal tDCS of LTA induces a similar transient tinnitus reduction as high-frequency rTMS.

  16. A feasible repetitive transcranial magnetic stimulation clinical protocol in migraine prevention

    PubMed Central

    Zardouz, Shawn; Shi, Lei; Leung, Albert

    2016-01-01

    Objective: This case series was conducted to determine the clinical feasibility of a repetitive transcranial magnetic stimulation protocol for the prevention of migraine (with and without aura). Methods: Five patients with migraines underwent five repetitive transcranial magnetic stimulation sessions separated in 1- to 2-week intervals for a period of 2 months at a single tertiary medical center. Repetitive transcranial magnetic stimulation was applied to the left motor cortex with 2000 pulses (20 trains with 1s inter-train interval) delivered per session, at a frequency of 10 Hz and 80% resting motor threshold. Pre- and post-treatment numerical rating pain scales were collected, and percent reductions in intensity, frequency, and duration were generated. Results: An average decrease in 37.8%, 32.1%, and 31.2% were noted in the intensity, frequency, and duration of migraines post-repetitive transcranial magnetic stimulation, respectively. A mean decrease in 1.9±1.0 (numerical rating pain scale ± standard deviation; range: 0.4–2.8) in headache intensity scores was noted after the repetitive transcranial magnetic stimulation sessions. Conclusion: The tested repetitive transcranial magnetic stimulation protocol is a well-tolerated, safe, and effective method for migraine prevention. PMID:27826448

  17. Hemicerebellectomy impairs the modulation of cutaneomuscular reflexes by the motor cortex following repetitive somatosensory stimulation.

    PubMed

    Oulad Ben Taib, Nordeyn; Manto, Mario

    2006-05-23

    We examined the cutaneomuscular reflex of the plantaris muscle of rats in response to cutaneous stimulation in isolation and in conjunction with subthreshold high-frequency trains of stimuli applied on the motor cortex, prior to and following repetitive peripheral stimulation. The cutaneomuscular reflex was also investigated under the same paradigm following hemicerebellectomy. The enhancement of cutaneomuscular responses associated with subthreshold high-frequency trains of stimulation following repetitive peripheral stimulation was prevented by hemicerebellectomy. Our results suggest that the pathways passing through the cerebellum are involved in the calibration of cutaneomuscular responses.

  18. Effects of repetitive facilitative exercise with neuromuscular electrical stimulation, vibratory stimulation and repetitive transcranial magnetic stimulation of the hemiplegic hand in chronic stroke patients.

    PubMed

    Etoh, Seiji; Noma, Tomokazu; Takiyoshi, Yuko; Arima, Michiko; Ohama, Rintaro; Yokoyama, Katsuya; Hokazono, Akihiko; Amano, Yumeko; Shimodozono, Megumi; Kawahira, Kazumi

    2016-11-01

    Repetitive facilitative exercise (RFE) is a developed approach to the rehabilitation of hemiplegia. RFE can be integrated with neuromuscular electrical stimulation (NMES), direct application of vibratory stimulation (DAVS) and repetitive transcranial magnetic stimulation (rTMS). The aims of the present study were to retrospectively compare the effects of RFE and NMES, DAVS with those of RFE and rTMS, and to determine the maximal effect of the combination of RFE with NMES, DAVS, rTMS and pharmacological treatments in stroke patients. Thirty-three stroke patients were enrolled and divided into three groups: 15 who received RFE with rTMS (4 min) (TMS4 alone), 9 who received RFE with NMES, DAVS (NMES, DAVS alone) and 9 who received RFE with NMES, DAVS and rTMS (10 min) (rTMS10 + NMES, DAVS). The subjects performed the Fugl-Meyer Assessment (FMA) and Action Research Arm Test (ARAT) before and after the 2-week session. The 18 patients in the NMES, DAVS alone and rTMS10 + NMES, DAVS group underwent the intervention for 4 weeks. There were no significant differences in the increases in the FMA, ARAT scores in the three groups. The FMA or ARAT scores in the NMES, DAVS alone and the rTMS10 + NMES, DAVS group were increased significantly. The FMA and ARAT scores were significantly improved after 4 weeks in the NMES, DAVS alone group. RFE with NMES, DAVS may be more effective than RFE with rTMS for the recovery of upper-limb function. Patients who received RFE with NMES, DAVS and pharmacological treatments showed significant functional recovery.

  19. Repetitive transcranial magnetic stimulation and transcranial direct current stimulation in motor rehabilitation after stroke: an update.

    PubMed

    Klomjai, W; Lackmy-Vallée, A; Roche, N; Pradat-Diehl, P; Marchand-Pauvert, V; Katz, R

    2015-09-01

    Stroke is a leading cause of adult motor disability. The number of stroke survivors is increasing in industrialized countries, and despite available treatments used in rehabilitation, the recovery of motor functions after stroke is often incomplete. Studies in the 1980s showed that non-invasive brain stimulation (mainly repetitive transcranial magnetic stimulation [rTMS] and transcranial direct current stimulation [tDCS]) could modulate cortical excitability and induce plasticity in healthy humans. These findings have opened the way to the therapeutic use of the 2 techniques for stroke. The mechanisms underlying the cortical effect of rTMS and tDCS differ. This paper summarizes data obtained in healthy subjects and gives a general review of the use of rTMS and tDCS in stroke patients with altered motor functions. From 1988 to 2012, approximately 1400 publications were devoted to the study of non-invasive brain stimulation in humans. However, for stroke patients with limb motor deficit, only 141 publications have been devoted to the effects of rTMS and 132 to those of tDCS. The Cochrane review devoted to the effects of rTMS found 19 randomized controlled trials involving 588 patients, and that devoted to tDCS found 18 randomized controlled trials involving 450 patients. Without doubt, rTMS and tDCS contribute to physiological and pathophysiological studies in motor control. However, despite the increasing number of studies devoted to the possible therapeutic use of non-invasive brain stimulation to improve motor recovery after stroke, further studies will be necessary to specify their use in rehabilitation.

  20. Facilitating effect of 15-Hz repetitive transcranial magnetic stimulation on tactile perceptual learning.

    PubMed

    Karim, Ahmed A; Schüler, Anne; Hegner, Yiwen Li; Friedel, Eva; Godde, Ben

    2006-09-01

    Recent neuroimaging studies have revealed that tactile perceptual learning can lead to substantial reorganizational changes of the brain. We report here for the first time that combining high-frequency (15 Hz) repetitive transcranial magnetic stimulation (rTMS) over the primary somatosensory cortex (SI) with tactile discrimination training is capable of facilitating operant perceptual learning. Most notably, increasing the excitability of SI by 15-Hz rTMS improved perceptual learning in spatial, but not in temporal, discrimination tasks. These findings give causal support to recent correlative data obtained by functional magnetic resonance imaging studies indicating a differential role of SI in spatial and temporal discrimination learning. The introduced combination of rTMS and tactile discrimination training may provide new therapeutical potentials in facilitating neuropsychological rehabilitation of functional deficits after lesions of the somatosensory cortex.

  1. Normalization of sensorimotor integration by repetitive transcranial magnetic stimulation in cervical dystonia.

    PubMed

    Zittel, S; Helmich, R C; Demiralay, C; Münchau, A; Bäumer, T

    2015-08-01

    Previous studies indicated that sensorimotor integration and plasticity of the sensorimotor system are impaired in dystonia patients. We investigated motor evoked potential amplitudes and short latency afferent inhibition to examine corticospinal excitability and cortical sensorimotor integration, before and after inhibitory 1 Hz repetitive transcranial magnetic stimulation over primary sensory and primary motor cortex in patients with cervical dystonia (n = 12). Motor evoked potentials were recorded from the right first dorsal interosseous muscle after application of unconditioned transcranial magnetic test stimuli and after previous conditioning electrical stimulation of the right index finger at short interstimulus intervals of 25, 30 and 40 ms. Results were compared to a group of healthy age-matched controls. At baseline, motor evoked potential amplitudes did not differ between groups. Short latency afferent inhibition was reduced in cervical dystonia patients compared to healthy controls. Inhibitory 1 Hz sensory cortex repetitive transcranial magnetic stimulation but not motor cortex repetitive transcranial magnetic stimulation increased motor evoked potential amplitudes in cervical dystonia patients. Additionally, both 1 Hz repetitive transcranial magnetic stimulation over primary sensory and primary motor cortex normalized short latency afferent inhibition in these patients. In healthy subjects, sensory repetitive transcranial magnetic stimulation had no influence on motor evoked potential amplitudes and short latency afferent inhibition. Plasticity of sensorimotor circuits is altered in cervical dystonia patients.

  2. Brain topological correlates of motor performance changes after repetitive transcranial magnetic stimulation.

    PubMed

    Park, Chang-hyun; Chang, Won Hyuk; Yoo, Woo-Kyoung; Shin, Yong-Il; Kim, Sung Tae; Kim, Yun-Hee

    2014-05-01

    Repetitive transcranial magnetic stimulation (rTMS) influences the brain temporally beyond the stimulation period and spatially beyond the stimulation site. Application of rTMS over the primary motor cortex (M1) has been shown to lead to plastic changes in interregional connectivity over the motor system as well as alterations in motor performance. With a sequential combination of rTMS over the M1 and functional magnetic resonance imaging (fMRI), we sought changes in the topology of brain networks and specifically the association of brain topological changes with motor performance changes. In a sham-controlled parallel group experimental design, real or sham rTMS was administered to each of the 15 healthy subjects without prior motor-related dysfunctions, over the right M1 at a high frequency of 10 Hz. Before and after the intervention, fMRI data were acquired during a sequential finger motor task using the left, nondominant hand. Changes in the topology of brain networks were assessed in terms of global and local efficiency, which measures the efficiency in transporting information at global and local scales, respectively, provided by graph-theoretical analysis. Greater motor performance changes toward improvements after real rTMS were shown in individuals who exhibited more increases in global efficiency and more decreases in local efficiency. The enhancement of motor performance after rTMS is supposed to be associated with brain topological changes, such that global information exchange is facilitated, while local information exchange is restricted.

  3. Influence of repetitive peripheral magnetic stimulation on neural plasticity in the motor cortex related to swallowing.

    PubMed

    Momosaki, Ryo; Kakuda, Wataru; Yamada, Naoki; Abo, Masahiro

    2016-09-01

    The aim of this study was to evaluate the effect of repetitive peripheral magnetic stimulation at two different frequencies (20 and 30 Hz) on cortical excitability in motor areas related to swallowing in healthy individuals. The study participants were 10 healthy normal volunteers (two women and eight men, age range 25-36 years). Repetitive peripheral magnetic stimulation was applied to the submandibular muscle using a parabolic coil at the site where contraction of the suprahyoid muscles was elicited. Stimulation was continued for 10 min (total 1200 pulses) at 20 Hz on 1 day and at 30 Hz on another day, with the stimulation strength set at 90% of the intensity that elicited pain. The motor-evoked potential amplitude of suprahyoid muscles was assessed before, immediately after, and 30 min after stimulation. Stimulations at both 20 and 30 Hz significantly increased motor-evoked potential amplitude (P<0.05), with the increase maintained until 30 min after stimulation. The motor-evoked potential amplitude immediately after stimulation was not significantly different between the 20 and 30 Hz frequencies. The results indicated that repetitive magnetic stimulation increased motor-evoked potential amplitude of swallowing muscles, suggesting facilitation of the motor cortex related to swallowing in healthy individuals.

  4. Immediate Effects of Repetitive Magnetic Stimulation on Single Cortical Pyramidal Neurons

    PubMed Central

    Banerjee, Jineta; Sorrell, Mary E.; Celnik, Pablo A.; Pelled, Galit

    2017-01-01

    Repetitive Transcranial Magnetic Stimulation (rTMS) has been successfully used as a non-invasive therapeutic intervention for several neurological disorders in the clinic as well as an investigative tool for basic neuroscience. rTMS has been shown to induce long-term changes in neuronal circuits in vivo. Such long-term effects of rTMS have been investigated using behavioral, imaging, electrophysiological, and molecular approaches, but there is limited understanding of the immediate effects of TMS on neurons. We investigated the immediate effects of high frequency (20 Hz) rTMS on the activity of cortical neurons in an effort to understand the underlying cellular mechanisms activated by rTMS. We used whole-cell patch-clamp recordings in acute rat brain slices and calcium imaging of cultured primary neurons to examine changes in neuronal activity and intracellular calcium respectively. Our results indicate that each TMS pulse caused an immediate and transient activation of voltage gated sodium channels (9.6 ± 1.8 nA at -45 mV, p value < 0.01) in neurons. Short 500 ms 20 Hz rTMS stimulation induced action potentials in a subpopulation of neurons, and significantly increased the steady state current of the neurons at near threshold voltages (at -45 mV: before TMS: I = 130 ± 17 pA, during TMS: I = 215 ± 23 pA, p value = 0.001). rTMS stimulation also led to a delayed increase in intracellular calcium (153.88 ± 61.94% increase from baseline). These results show that rTMS has an immediate and cumulative effect on neuronal activity and intracellular calcium levels, and suggest that rTMS may enhance neuronal responses when combined with an additional motor, sensory or cognitive stimulus. Thus, these results could be translated to optimize rTMS protocols for clinical as well as basic science applications. PMID:28114421

  5. Repetitive Transcranial Magnetic Stimulation to the Primary Motor Cortex Interferes with Motor Learning by Observing

    ERIC Educational Resources Information Center

    Brown, Liana E.; Wilson, Elizabeth T.; Gribble, Paul L.

    2009-01-01

    Neural representations of novel motor skills can be acquired through visual observation. We used repetitive transcranial magnetic stimulation (rTMS) to test the idea that this "motor learning by observing" is based on engagement of neural processes for learning in the primary motor cortex (M1). Human subjects who observed another person learning…

  6. Repetitive Transcranial Magnetic Stimulation in Resistant Visual Hallucinations in a Woman With Schizophrenia: A Case Report.

    PubMed

    Ghanbari Jolfaei, Atefeh; Naji, Borzooyeh; Nasr Esfehani, Mehdi

    2016-03-01

    A 29-year-old woman with schizophrenia introduced for application of repetitive transcranial magnetic stimulation for refractory visual hallucinations. Following inhibitory rTMS on visual cortex she reported significant reduction in severity and simplification of complexity of hallucinations, which lasted for three months. rTMS can be considered as a possibly potent treatment for visual hallucinations.

  7. Repetitive magnetic stimulation affects the microenvironment of nerve regeneration and evoked potentials after spinal cord injury.

    PubMed

    Jiang, Jin-Lan; Guo, Xu-Dong; Zhang, Shu-Quan; Wang, Xin-Gang; Wu, Shi-Feng

    2016-05-01

    Repetitive magnetic stimulation has been shown to alter local blood flow of the brain, excite the corticospinal tract and muscle, and induce motor function recovery. We established a rat model of acute spinal cord injury using the modified Allen's method. After 4 hours of injury, rat models received repetitive magnetic stimulation, with a stimulus intensity of 35% maximum output intensity, 5-Hz frequency, 5 seconds for each sequence, and an interval of 2 minutes. This was repeated for a total of 10 sequences, once a day, 5 days in a week, for 2 consecutive weeks. After repetitive magnetic stimulation, the number of apoptotic cells decreased, matrix metalloproteinase 9/2 gene and protein expression decreased, nestin expression increased, somatosensory and motor-evoked potentials recovered, and motor function recovered in the injured spinal cord. These findings confirm that repetitive magnetic stimulation of the spinal cord improved the microenvironment of neural regeneration, reduced neuronal apoptosis, and induced neuroprotective and repair effects on the injured spinal cord.

  8. Repetitive Transcranial Magnetic Stimulation in Resistant Visual Hallucinations in a Woman With Schizophrenia: A Case Report

    PubMed Central

    Ghanbari Jolfaei, Atefeh; Naji, Borzooyeh; Nasr Esfehani, Mehdi

    2016-01-01

    A 29-year-old woman with schizophrenia introduced for application of repetitive transcranial magnetic stimulation for refractory visual hallucinations. Following inhibitory rTMS on visual cortex she reported significant reduction in severity and simplification of complexity of hallucinations, which lasted for three months. rTMS can be considered as a possibly potent treatment for visual hallucinations. PMID:27284279

  9. Repetitive Transcranial Magnetic Stimulation to the Primary Motor Cortex Interferes with Motor Learning by Observing

    ERIC Educational Resources Information Center

    Brown, Liana E.; Wilson, Elizabeth T.; Gribble, Paul L.

    2009-01-01

    Neural representations of novel motor skills can be acquired through visual observation. We used repetitive transcranial magnetic stimulation (rTMS) to test the idea that this "motor learning by observing" is based on engagement of neural processes for learning in the primary motor cortex (M1). Human subjects who observed another person learning…

  10. Repetitive transcranial magnetic stimulation for clinical applications in neurological and psychiatric disorders: an overview.

    PubMed

    Machado, Sergio; Arias-Carrión, Oscar; Paes, Flávia; Vieira, Renata Teles; Caixeta, Leonardo; Novaes, Felipe; Marinho, Tamires; Almada, Leonardo Ferreira; Silva, Adriana Cardoso; Nardi, Antonio Egidio

    2013-10-01

    Neurological and psychiatric disorders are characterized by several disabling symptoms for which effective, mechanism-based treatments remain elusive. Consequently, more advanced non-invasive therapeutic methods are required. A method that may modulate brain activity and be viable for use in clinical practice is repetitive transcranial magnetic stimulation (rTMS). It is a non-invasive procedure whereby a pulsed magnetic field stimulates electrical activity in the brain. Here, we focus on the basic foundation of rTMS, the main stimulation parametters, the factors that influence individual responses to rTMS and the experimental advances of rTMS that may become a viable clinical application to treat neurological and psychiatric disorders. The findings showed that rTMS can improve some symptoms associated with these conditions and might be useful for promoting cortical plasticity in patients with neurological and psychiatric disorders. However, these changes are transient and it is premature to propose these applications as realistic therapeutic options, even though the rTMS technique has been evidenced as a potential modulator of sensorimotor integration and neuroplasticity. Functional imaging of the region of interest could highlight the capacity of rTMS to bring about plastic changes of the cortical circuitry and hint at future novel clinical interventions. Thus, we recommend that further studies clearly determine the role of rTMS in the treatment of these conditions. Finally, we must remember that however exciting the neurobiological mechanisms might be, the clinical usefulness of rTMS will be determined by its ability to provide patients with neurological and psychiatric disorders with safe, long-lasting and substantial improvements in quality of life.

  11. Repetitive Transcranial Magnetic Stimulation for Clinical Applications in Neurological and Psychiatric Disorders: An Overview

    PubMed Central

    Machado, Sergio; Arias-Carrión, Oscar; Paes, Flávia; Vieira, Renata Teles; Caixeta, Leonardo; Novaes, Felipe; Marinho, Tamires; Almada, Leonardo Ferreira; Silva, Adriana Cardoso; Nardi, Antonio Egidio

    2013-01-01

    Neurological and psychiatric disorders are characterized by several disabling symptoms for which effective, mechanism-based treatments remain elusive. Consequently, more advanced non-invasive therapeutic methods are required. A method that may modulate brain activity and be viable for use in clinical practice is repetitive transcranial magnetic stimulation (rTMS). It is a non-invasive procedure whereby a pulsed magnetic field stimulates electrical activity in the brain. Here, we focus on the basic foundation of rTMS, the main stimulation parametters, the factors that influence individual responses to rTMS and the experimental advances of rTMS that may become a viable clinical application to treat neurological and psychiatric disorders. The findings showed that rTMS can improve some symptoms associated with these conditions and might be useful for promoting cortical plasticity in patients with neurological and psychiatric disorders. However, these changes are transient and it is premature to propose these applications as realistic therapeutic options, even though the rTMS technique has been evidenced as a potential modulator of sensorimotor integration and neuroplasticity. Functional imaging of the region of interest could highlight the capacity of rTMS to bring about plastic changes of the cortical circuitry and hint at future novel clinical interventions. Thus, we recommend that further studies clearly determine the role of rTMS in the treatment of these conditions. Finally, we must remember that however exciting the neurobiological mechanisms might be, the clinical usefulness of rTMS will be determined by its ability to provide patients with neurological and psychiatric disorders with safe, long-lasting and substantial improvements in quality of life. PMID:25610279

  12. Repetitive transcranial magnetic stimulation over the supplementary motor area modifies breathing pattern in response to inspiratory loading in normal humans

    PubMed Central

    Nierat, Marie-Cécile; Hudson, Anna L.; Chaskalovic, Joël; Similowski, Thomas; Laviolette, Louis

    2015-01-01

    In awake humans, breathing depends on automatic brainstem pattern generators. It is also heavily influenced by cortical networks. For example, functional magnetic resonance imaging and electroencephalographic data show that the supplementary motor area becomes active when breathing is made difficult by inspiratory mechanical loads like resistances or threshold valves, which is associated with perceived respiratory discomfort. We hypothesized that manipulating the excitability of the supplementary motor area with repetitive transcranial magnetic stimulation would modify the breathing pattern response to an experimental inspiratory load and possibly respiratory discomfort. Seven subjects (three men, age 25 ± 4) were studied. Breathing pattern and respiratory discomfort during inspiratory loading were described before and after conditioning the supplementary motor area with repetitive stimulation, using an excitatory paradigm (5 Hz stimulation), an inhibitory paradigm, or sham stimulation. No significant change in breathing pattern during loading was observed after sham conditioning. Excitatory conditioning shortened inspiratory time (p = 0.001), decreased tidal volume (p = 0.016), and decreased ventilation (p = 0.003), as corroborated by an increased end-tidal expired carbon dioxide (p = 0.013). Inhibitory conditioning did not affect ventilation, but lengthened expiratory time (p = 0.031). Respiratory discomfort was mild under baseline conditions, and unchanged after conditioning of the supplementary motor area. This is the first study to show that repetitive transcranial magnetic stimulation conditioning of the cerebral cortex can alter breathing pattern. A 5 Hz conditioning protocol, known to enhance corticophrenic excitability, can reduce the amount of hyperventilation induced by inspiratory threshold loading. Further studies are needed to determine whether and under what circumstances rTMS can have an effect on dyspnoea. PMID:26483701

  13. Remodeling Brain Activity by Repetitive Cervicothoracic Transspinal Stimulation after Human Spinal Cord Injury

    PubMed Central

    Murray, Lynda M.; Knikou, Maria

    2017-01-01

    Interventions that can produce targeted brain plasticity after human spinal cord injury (SCI) are needed for restoration of impaired movement in these patients. In this study, we tested the effects of repetitive cervicothoracic transspinal stimulation in one person with cervical motor incomplete SCI on cortical and corticospinal excitability, which were assessed via transcranial magnetic stimulation with paired and single pulses, respectively. We found that repetitive cervicothoracic transspinal stimulation potentiated intracortical facilitation in flexor and extensor wrist muscles, recovered intracortical inhibition in the more impaired wrist flexor muscle, increased corticospinal excitability bilaterally, and improved voluntary muscle strength. These effects may have been mediated by improvements in cortical integration of ascending sensory inputs and strengthening of corticospinal connections. Our novel therapeutic intervention opens new avenues for targeted brain neuromodulation protocols in individuals with cervical motor incomplete SCI. PMID:28265259

  14. Repetitive transcranial magnetic stimulation for the treatment of chronic tinnitus after traumatic brain injury: a case study.

    PubMed

    Kreuzer, Peter Michael; Landgrebe, Michael; Frank, Elmar; Langguth, Berthold

    2013-01-01

    Tinnitus is a frequent symptom of traumatic brain injury, which is difficult to treat. Repetitive transcranial magnetic stimulation has shown beneficial effects in some forms of tinnitus. However, traumatic brain injury in the past has been considered as a relative contraindication for repetitive transcranial magnetic stimulation because of the increased risk of seizures. Here we present the case of a 53-year-old male patient suffering from severe tinnitus after traumatic brain injury with comorbid depression and alcohol abuse, who received 5 treatment series of repetitive transcranial magnetic stimulation (1 Hz stimulation protocol over left primary auditory cortex, 10 sessions of 2000 stimuli each, stimulation intensity 110% resting motor threshold). Repetitive transcranial magnetic stimulation was tolerated without any side effects and tinnitus complaints (measured by a validated tinnitus questionnaire and numeric rating scales) were improved in a replicable way throughout 5 courses of transcranial magnetic stimulation up to now.

  15. The Effectiveness of Repetitive Transcranial Magnetic Stimulation for Poststroke Apathy Is Associated with Improved Interhemispheric Functional Connectivity.

    PubMed

    Mitaki, Shingo; Onoda, Keiichi; Abe, Satoshi; Oguro, Hiroaki; Yamaguchi, Shuhei

    2016-12-01

    Poststroke apathy is relatively common and has negative effects on the functional recovery of the patient; however, few reports have demonstrated the existence of effective treatments for poststroke apathy. Here, we describe a case of poststroke apathy that was successfully treated with repetitive transcranial magnetic stimulation (rTMS). Using resting-state functional magnetic resonance imaging, we detected improved interhemispheric functional connectivity that was correlated with the patient's recovery from poststroke apathy. Our case suggests that rTMS can improve the transfer of information through the corpus callosum, which is crucial for helping patients recover from poststroke apathy. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  16. Deep brain stimulation improves movement amplitude but not hastening of repetitive finger movements.

    PubMed

    Stegemöller, Elizabeth L; Zadikoff, Cindy; Rosenow, Joshua M; Mackinnon, Colum D

    2013-09-27

    External pacing cues, dopaminergic medication, and bilateral subthalamic nucleus deep brain stimulation (STN-DBS) improve repetitive movements performed at low rates. When the pacing rate is increased to frequencies near 2 Hz and above, both external pacing cues and Parkinson's medication were shown to be ineffective at improving repetitive finger movement performance. It remains unclear if STN-DBS improves the performance of repetitive finger movements at high pacing rates. This study examined the effects of STN-DBS on the amplitude and rate of repetitive finger movement across a range of external pacing rates. Nine participants with STN-DBS (OFF and ON stimulation) and nine matched healthy adults performed repetitive index finger flexion movements paced by an acoustic tone that increased from 1.0 to 3.0 Hz. OFF stimulation, most subjects moved at rates that were substantially higher (hastening pattern) or lower (bradykinesia pattern) than the tone rate, particularly at high pacing rates. ON stimulation, movement rate improved in subjects with the bradykinesia pattern, but not in those with the hastening pattern. Overall, STN-DBS did not significantly affect movement rate. In contrast, STN-DBS significantly (p<0.05) improved movement amplitude across all pacing rates. These findings demonstrate that STN-DBS improves movement amplitude, but had no effect on the rate of movement in participants with a hastening pattern. Separately testing movement amplitude and movement rate using both high and low rate externally paced cues in the clinical environment may aid in the diagnosis and treatment of people with Parkinson's disease. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  17. Cerebral Functional Reorganization in Ischemic Stroke after Repetitive Transcranial Magnetic Stimulation: An fMRI Study.

    PubMed

    Li, Jing; Zhang, Xue-Wei; Zuo, Zhen-Tao; Lu, Jie; Meng, Chun-Ling; Fang, Hong-Ying; Xue, Rong; Fan, Yong; Guan, Yu-Zhou; Zhang, Wei-Hong

    2016-12-01

    Our study aimed to figure out brain functional reorganization evidence after repetitive transcranial magnetic stimulation (rTMS) using the resting-state functional magnetic resonance imaging (rsfMRI). Twelve patients with unilateral subcortex lesion in the middle cerebral artery territory were recruited. Seven of them received a 10-day rTMS treatment beginning at about 5 days after stroke onset. The remaining five received sham treatment. RsfMRI and motor functional scores were obtained before and after rTMS or sham rTMS. The rTMS group showed motor recovery according to the behavioral testing scores, while there was no significant difference of motor functional scores in the sham group before and after the sham rTMS. It proved that rTMS facilitates motor recovery of early ischemic stroke patients. Compared with the sham, the rTMS treatment group achieved increased functional connectivity (FC) between ipsilesional M1 and contralesional M1, supplementary motor area, bilateral thalamus, and contralesional postcentral gyrus. And decreased FC was found between ipsilesional M1 and ipsilesional M1, postcentral gyrus and inferior and middle frontal gyrus. Increased or decreased FC detected by rsfMRI is an important finding to understand the mechanism of brain functional reorganization. The rTMS treatment is a promising therapeutic approach to facilitate motor rehabilitation for early stroke patients. © 2016 John Wiley & Sons Ltd.

  18. CALCIUM PLAYS A CENTRAL ROLE IN THE SENSITIZATION OF TRPV3 CHANNEL TO REPETITIVE STIMULATIONS

    PubMed Central

    Xiao, Rui; Tang, Jisen; Wang, Chunbo; Colton, Craig K.; Tian, Jinbin; Zhu, Michael X.

    2008-01-01

    Transient Receptor Potential (TRP) channels are involved in sensing chemical and physical changes inside and outside of cells. TRPV3 is highly expressed in skin keratinocytes, where it forms a non-selective cation channel activated by hot temperatures in the innocuous and noxious range. The channel has also been implicated in flavor sensation in oral and nasal cavities as well as being a molecular target of some allergens and skin sensitizers. TRPV3 is unique in that its activity is sensitized upon repetitive stimulations. Here, we investigated the role of calcium ions in the sensitization of TRPV3 to repetitive stimulations. We show that the sensitization is accompanied with a decrease of Ca2+-dependent channel inhibition mediated by calmodulin acting at an N-terminal site (aa 108-130) and by an acidic residue (Asp641) at the pore loop of TRPV3. These sites also contribute to the voltage dependence of TRPV3. During sensitization, the channel displayed a gradual shift of the voltage dependence to more negative potentials as well as uncoupling from voltage sensing. The initial response to ligand stimulation was increased and sensitization to repetitive stimulations was decreased by increasing the intracellular Ca2+ buffering strength, inhibiting calmodulin, or disrupting the calmodulin-binding site. Mutation of Asp641 to Asn abolished the high affinity extracellular Ca2+-mediated inhibition and greatly facilitated the activation of TRPV3. We conclude that Ca2+ inhibits TRPV3 from both the extracellular and intracellular sides. The inhibition is sequentially reduced, appearing as sensitization to repetitive stimulations. PMID:18178557

  19. Non-invasive mapping of calculation function by repetitive navigated transcranial magnetic stimulation.

    PubMed

    Maurer, Stefanie; Tanigawa, Noriko; Sollmann, Nico; Hauck, Theresa; Ille, Sebastian; Boeckh-Behrens, Tobias; Meyer, Bernhard; Krieg, Sandro M

    2016-11-01

    Concerning calculation function, studies have already reported on localizing computational function in patients and volunteers by functional magnetic resonance imaging and transcranial magnetic stimulation. However, the development of accurate repetitive navigated TMS (rTMS) with a considerably higher spatial resolution opens a new field in cognitive neuroscience. This study was therefore designed to evaluate the feasibility of rTMS for locating cortical calculation function in healthy volunteers, and to establish this technique for future scientific applications as well as preoperative mapping in brain tumor patients. Twenty healthy subjects underwent rTMS calculation mapping using 5 Hz/10 pulses. Fifty-two previously determined cortical spots of the whole hemispheres were stimulated on both sides. The subjects were instructed to perform the calculation task composed of 80 simple arithmetic operations while rTMS pulses were applied. The highest error rate (80 %) for all errors of all subjects was observed in the right ventral precentral gyrus. Concerning division task, a 45 % error rate was achieved in the left middle frontal gyrus. The subtraction task showed its highest error rate (40 %) in the right angular gyrus (anG). In the addition task a 35 % error rate was observed in the left anterior superior temporal gyrus. Lastly, the multiplication task induced a maximum error rate of 30 % in the left anG. rTMS seems feasible as a way to locate cortical calculation function. Besides language function, the cortical localizations are well in accordance with the current literature for other modalities or lesion studies.

  20. Measurement of motor evoked potentials following repetitive magnetic motor cortex stimulation during isoflurane or propofol anaesthesia.

    PubMed

    Rohde, V; Krombach, G A; Baumert, J H; Kreitschmann-Andermahr, I; Weinzierl, M; Gilsbach, J M

    2003-10-01

    Isoflurane and propofol reduce the recordability of compound muscle action potentials (CMAP) following single transcranial magnetic stimulation of the motor cortex (sTCMS). Repetition of the magnetic stimulus (repetitive transcranial magnetic stimulation, rTCMS) might allow the inhibition caused by anaesthesia with isoflurane or propofol to be overcome. We applied rTCMS (four stimuli; inter-stimulus intervals of 3, 4, 5 ms (333, 250, 200 Hz), output 2.5 Tesla) in 27 patients and recorded CMAP from the hypothenar and anterior tibial muscle. Anaesthesia was maintained with fentanyl 0.5-1 microg kg(-1) x h(-1) and either isoflurane 1.2% (10 patients) or propofol 5 mg kg(-1) x h(-1) with nitrous oxide 60% in oxygen (17 patients). No CMAP were detected during isoflurane anaesthesia. During propofol anaesthesia 333 Hz, four-pulse magnetic stimulation evoked CMAP in the hypothenar muscle in 75%, and in the anterior tibial muscle in 65% of the patients. Less response was obtained with 250 and 200 Hz stimulation. In most patients, rTCMS can overcome suppression of CMAP during propofol/nitrous oxide anaesthesia, but not during isoflurane anaesthesia. A train of four magnetic stimuli at a frequency of 333 Hz is most effective in evoking potentials from the upper and lower limb muscles. The authors conclude that rTCMS can be used for evaluation of the descending motor pathways during anaesthesia.

  1. The effect of 10 Hz repetitive transcranial magnetic stimulation of posterior parietal cortex on visual attention.

    PubMed

    Dombrowe, Isabel; Juravle, Georgiana; Alavash, Mohsen; Gießing, Carsten; Hilgetag, Claus C

    2015-01-01

    Repetitive transcranial magnetic stimulation (rTMS) of the posterior parietal cortex (PPC) at frequencies lower than 5 Hz transiently inhibits the stimulated area. In healthy participants, such a protocol can induce a transient attentional bias to the visual hemifield ipsilateral to the stimulated hemisphere. This bias might be due to a relatively less active stimulated hemisphere and a relatively more active unstimulated hemisphere. In a previous study, Jin and Hilgetag (2008) tried to switch the attention bias from the hemifield ipsilateral to the hemifield contralateral to the stimulated hemisphere by applying high frequency rTMS. High frequency rTMS has been shown to excite, rather than inhibit, the stimulated brain area. However, the bias to the ipsilateral hemifield was still present. The participants' performance decreased when stimuli were presented in the hemifield contralateral to the stimulation site. In the present study we tested if this unexpected result was related to the fact that participants were passively resting during stimulation rather than performing a task. Using a fully crossed factorial design, we compared the effects of high frequency rTMS applied during a visual detection task and high frequency rTMS during passive rest on the subsequent offline performance in the same detection task. Our results were mixed. After sham stimulation, performance was better after rest than after task. After active 10 Hz rTMS, participants' performance was overall better after task than after rest. However, this effect did not reach statistical significance. The comparison of performance after rTMS with task and performance after sham stimulation with task showed that 10 Hz stimulation significantly improved performance in the whole visual field. Thus, although we found a trend to better performance after rTMS with task than after rTMS during rest, we could not reject the hypothesis that high frequency rTMS with task and high frequency rTMS during rest

  2. The Effect of 10 Hz Repetitive Transcranial Magnetic Stimulation of Posterior Parietal Cortex on Visual Attention

    PubMed Central

    Dombrowe, Isabel; Juravle, Georgiana; Alavash, Mohsen; Gießing, Carsten; Hilgetag, Claus C.

    2015-01-01

    Repetitive transcranial magnetic stimulation (rTMS) of the posterior parietal cortex (PPC) at frequencies lower than 5 Hz transiently inhibits the stimulated area. In healthy participants, such a protocol can induce a transient attentional bias to the visual hemifield ipsilateral to the stimulated hemisphere. This bias might be due to a relatively less active stimulated hemisphere and a relatively more active unstimulated hemisphere. In a previous study, Jin and Hilgetag (2008) tried to switch the attention bias from the hemifield ipsilateral to the hemifield contralateral to the stimulated hemisphere by applying high frequency rTMS. High frequency rTMS has been shown to excite, rather than inhibit, the stimulated brain area. However, the bias to the ipsilateral hemifield was still present. The participants’ performance decreased when stimuli were presented in the hemifield contralateral to the stimulation site. In the present study we tested if this unexpected result was related to the fact that participants were passively resting during stimulation rather than performing a task. Using a fully crossed factorial design, we compared the effects of high frequency rTMS applied during a visual detection task and high frequency rTMS during passive rest on the subsequent offline performance in the same detection task. Our results were mixed. After sham stimulation, performance was better after rest than after task. After active 10 Hz rTMS, participants’ performance was overall better after task than after rest. However, this effect did not reach statistical significance. The comparison of performance after rTMS with task and performance after sham stimulation with task showed that 10 Hz stimulation significantly improved performance in the whole visual field. Thus, although we found a trend to better performance after rTMS with task than after rTMS during rest, we could not reject the hypothesis that high frequency rTMS with task and high frequency rTMS during rest

  3. Repetitive transcranial magnetic stimulation to improve mood and motor function in Parkinson's disease.

    PubMed

    Helmich, Rick C; Siebner, Hartwig R; Bakker, Maaike; Münchau, Alexander; Bloem, Bastiaan R

    2006-10-25

    Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive brain stimulation technique that can produce lasting changes in excitability and activity in cortical regions underneath the stimulation coil (local effect), but also within functionally connected cortical or subcortical regions (remote effects). Since the clinical presentation of Parkinson's disease (PD) is related to abnormal neuronal activity within the basal ganglia and cortical regions, including the primary motor cortex, the premotor cortex and the prefrontal cortex, several studies have used rTMS to improve brain function in PD. Here, we review the studies that have investigated the possible therapeutic effects of rTMS on mood and motor function in PD patients. We highlight some methodological inconsistencies and problems, including the difficulty to define the most effective protocol for rTMS or to establish an appropriate placebo condition. We finally propose future directions of research that may help to improve the therapeutic efficacy of rTMS in PD.

  4. Repetitive Transcranial Magnetic Stimulation in Cervical Dystonia: Effect of Site and Repetition in a Randomized Pilot Trial

    PubMed Central

    Pirio Richardson, Sarah; Tinaz, Sule; Chen, Robert

    2015-01-01

    Dystonia is characterized by abnormal posturing due to sustained muscle contraction, which leads to pain and significant disability. New therapeutic targets are needed in this disorder. The objective of this randomized, sham-controlled, blinded exploratory study is to identify a specific motor system target for non-invasive neuromodulation and to evaluate this target in terms of safety and tolerability in the cervical dystonia (CD) population. Eight CD subjects were given 15-minute sessions of low-frequency (0.2 Hz) repetitive transcranial magnetic stimulation (rTMS) over the primary motor cortex (MC), dorsal premotor cortex (dPM), supplementary motor area (SMA), anterior cingulate cortex (ACC) and a sham condition with each session separated by at least two days. The Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) score was rated in a blinded fashion immediately pre- and post-intervention. Secondary outcomes included physiology and tolerability ratings. The mean change in TWSTRS severity score by site was 0.25 ± 1.7 (ACC), -2.9 ± 3.4 (dPM), -3.0 ± 4.8 (MC), -0.5 ± 1.1 (SHAM), and -1.5 ± 3.2 (SMA) with negative numbers indicating improvement in symptom control. TWSTRS scores decreased from Session 1 (15.1 ± 5.1) to Session 5 (11.0 ± 7.6). The treatment was tolerable and safe. Physiology data were acquired on 6 of 8 subjects and showed no change over time. These results suggest rTMS can modulate CD symptoms. Both dPM and MC are areas to be targeted in further rTMS studies. The improvement in TWSTRS scores over time with multiple rTMS sessions deserves further evaluation. Trial Registration ClinicalTrials.gov NCT01859247 PMID:25923718

  5. Prolonged enhancement of the micturition reflex in the cat by repetitive stimulation of bladder afferents

    PubMed Central

    Jiang, Chong-He; Lindström, Sivert

    1999-01-01

    Prolonged modulation of the parasympathetic micturition reflex was studied in cats anaesthetized by α-chloralose. Reflex discharges were recorded from a thin pelvic nerve filament to the bladder and evoked by stimulation of the remaining ipsilateral bladder pelvic nerves or urethral branches of the pudendal nerve. Stimulation of bladder or urethral afferents at Aδ intensity evoked micturition reflexes with a latency of 90-120 ms. Such reflexes were much enhanced following repetitive conditioning stimulation of the same afferents at 20 Hz for 5 min. The reflex enhancement lasted more than 1 h after the conditioning stimulation. The effect was not prevented by a preceding complete transection of the sympathetic supply to the bladder. A prolonged suppression of the reflex was obtained after conditioning stimulation of afferents in the dorsal clitoris nerves. It is proposed that the prolonged modulations of the micturition reflex represent physiological adaptive processes, which preserve a flawless function of the bladder during life. The observations provide a theoretical explanation for the beneficial effect of electric nerve stimulation in patients with voiding disorders. PMID:10332105

  6. [Repetitive Transcranial Magnetic Stimulation (rTMS) for Higher Brain Function Deficits].

    PubMed

    Inoue, Yukichi

    2016-12-01

    The management of higher brain dysfunctions such as stroke-induced unilateral spatial neglect (USN) or aphasia is crucial because these dysfunctions have devastating neurological repercussions on the patients' daily life and quality of life. Impairment of the physiological interhemispheric rivalry is often the result of brain insults such as strokes or traumatic injuries, and it may lead to USN or aphasia. Repetitive transcranial magnetic stimulation (rTMS), a non-invasive brain stimulation method, is a promising tool for restoring the pathological imbalance in interhemispheric rivalry by either suppressing the hyperactivity of the unaffected hemisphere or facilitating hypoactivity in the affected hemisphere. The concept of paradoxical functional facilitation (Kapur, 1996) has important clinical implications when coupled with rTMS applications. In addition to conventional rTMS (c-rTMS), other clinically relevant protocols of patterned rTMS (p-rTMS) have been developed: the theta burst stimulation (TBS), the paired associative stimulation (PAS), and the quadripulse stimulation (QPS). TBS is commonly used in the rehabilitation of patients with post-stroke USN and those with non-fluent aphasia because of its prolonged beneficial effects and the short duration of stimulation. TBS may be considered an effective and safe protocol of rTMS. We foresee broader clinical applications of p-rTMS (TBS) and c-rTMS in the treatment of various neurological deficits.

  7. Repetitive Transcranial Magnetic Stimulation for Wernicke-Korsakoff Syndrome: A Case Report

    PubMed Central

    2017-01-01

    A 57-year-old man who was diagnosed with Wernicke-Korsakoff syndrome showed severe impairment of cognitive function and a craving for alcohol, even after sufficient supplementation with thiamine. After completing 10 sessions of 10 Hz repetitive transcranial magnetic stimulation (rTMS) at 100% of the resting motor threshold over the left dorsolateral prefrontal cortex, dramatic improvement in cognitive function and a reduction in craving for alcohol were noted. This is the first case report of the efficacy of a high-frequency rTMS in the treatment of Wernicke-Korsakoff syndrome. PMID:28289650

  8. Repetitive Transcranial Magnetic Stimulation for Wernicke-Korsakoff Syndrome: A Case Report.

    PubMed

    Chung, So Won; Park, Shin Who; Seo, Young Jae; Kim, Jae-Hyung; Lee, Chan Ho; Lim, Jong Youb

    2017-02-01

    A 57-year-old man who was diagnosed with Wernicke-Korsakoff syndrome showed severe impairment of cognitive function and a craving for alcohol, even after sufficient supplementation with thiamine. After completing 10 sessions of 10 Hz repetitive transcranial magnetic stimulation (rTMS) at 100% of the resting motor threshold over the left dorsolateral prefrontal cortex, dramatic improvement in cognitive function and a reduction in craving for alcohol were noted. This is the first case report of the efficacy of a high-frequency rTMS in the treatment of Wernicke-Korsakoff syndrome.

  9. Effect of Epidural Electrical Stimulation and Repetitive Transcranial Magnetic Stimulation in Rats With Diffuse Traumatic Brain Injury

    PubMed Central

    Yoon, Yong-Soon; Cho, Kang Hee; Kim, Eun-Sil; Lee, Mi-Sook

    2015-01-01

    Objective To evaluate the effects of epidural electrical stimulation (EES) and repetitive transcranial magnetic stimulation (rTMS) on motor recovery and brain activity in a rat model of diffuse traumatic brain injury (TBI) compared to the control group. Methods Thirty rats weighing 270-285 g with diffuse TBI with 45 kg/cm2 using a weight-drop model were assigned to one of three groups: the EES group (ES) (anodal electrical stimulation at 50 Hz), the rTMS group (MS) (magnetic stimulation at 10 Hz, 3-second stimulation with 6-second intervals, 4,000 total stimulations per day), and the sham-treated control group (sham) (no stimulation). They were pre-trained to perform a single-pellet reaching task (SPRT) and a rotarod test (RRT) for 14 days. Diffuse TBI was then induced and an electrode was implanted over the dominant motor cortex. The changes in SPRT success rate, RRT performance time rate and the expression of c-Fos after two weeks of EES or rTMS were tracked. Results SPRT improved significantly from day 8 to day 12 in the ES group and from day 4 to day 14 in the MS group (p<0.05) compared to the sham group. RRT improved significantly from day 6 to day 11 in ES and from day 4 to day 9 in MS compared to the sham group. The ES and MS groups showed increased expression of c-Fos in the cerebral cortex compared to the sham group. Conclusion ES or MS in a rat model of diffuse TBI can be used to enhance motor recovery and brain activity. PMID:26161348

  10. Stimulated Brillouin Scattering Microscopic Imaging

    PubMed Central

    Ballmann, Charles W.; Thompson, Jonathan V.; Traverso, Andrew J.; Meng, Zhaokai; Scully, Marlan O.; Yakovlev, Vladislav V.

    2015-01-01

    Two-dimensional stimulated Brillouin scattering microscopy is demonstrated for the first time using low power continuous-wave lasers tunable around 780 nm. Spontaneous Brillouin spectroscopy has much potential for probing viscoelastic properties remotely and non-invasively on a microscopic scale. Nonlinear Brillouin scattering spectroscopy and microscopy may provide a way to tremendously accelerate the data aquisition and improve spatial resolution. This general imaging setup can be easily adapted for specific applications in biology and material science. The low power and optical wavelengths in the water transparency window used in this setup provide a powerful bioimaging technique for probing the mechanical properties of hard and soft tissue. PMID:26691398

  11. Daily left prefrontal repetitive transcranial magnetic stimulation for medication-resistant burning mouth syndrome.

    PubMed

    Umezaki, Y; Badran, B W; Gonzales, T S; George, M S

    2015-08-01

    Burning mouth syndrome (BMS) is a persistent and chronic burning sensation in the mouth in the absence of any abnormal organic findings. The pathophysiology of BMS is unclear and its treatment is not fully established. Although antidepressant medication is commonly used for treatment, there are some medication-resistant patients, and a new treatment for medication-resistant BMS is needed. Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive brain stimulation technology approved by the US Food and Drug Administration (FDA) for the treatment of depression. Recent studies have found beneficial effects of TMS for the treatment of pain. A case of BMS treated successfully with daily left prefrontal rTMS over a 2-week period is reported here. Based on this patient's clinical course and a recent pain study, the mechanism by which TMS may act to decrease the burning pain is discussed.

  12. [Repetitive transcranial magnetic stimulation. A method in the treatment of depressions].

    PubMed

    Hansen, P E

    2000-04-17

    Transcranial magnetic stimulation (TMS) has been used as a diagnostic tool in neurology for more than a decade. Recent research indicates that it when applied repeatedly as repetitive transcranial magnetic stimulation (rTMS) has an antidepressant effect. RTMS is based on the principle of electro-magnetism. An electromagnetic coil placed on the scalp produces a time-varying magnetic field, which gives rise to a current in the proximity of the cerebral cortex. Unlike electroconvulsive therapy (ECT) rTMS does normally not give rise to epileptic seizures and does not require anaesthesia. This review covers a critical summary of the literature on the subject. The results of recent placebo-controlled, randomized trials are promising. However, further investigations are required, before rTMS can be fully integrated in the antidepressant therapeutic armamentarium.

  13. Modulation of N400 in Chronic Non-Fluent Aphasia Using Low Frequency Repetitive Transcranial Magnetic Stimulation (rTMS)

    ERIC Educational Resources Information Center

    Barwood, Caroline H. S.; Murdoch, Bruce E.; Whelan, Brooke-Mai; Lloyd, David; Riek, Stephan; O'Sullivan, John D.; Coulthard, Alan; Wong, Andrew

    2011-01-01

    Low frequency Repetitive Transcranial Magnetic Stimulation (rTMS) has previously been applied to language homologues in non-fluent populations of persons with aphasia yielding significant improvements in behavioral language function up to 43 months post stimulation. The present study aimed to investigate the electrophysiological correlates…

  14. Modulation of N400 in Chronic Non-Fluent Aphasia Using Low Frequency Repetitive Transcranial Magnetic Stimulation (rTMS)

    ERIC Educational Resources Information Center

    Barwood, Caroline H. S.; Murdoch, Bruce E.; Whelan, Brooke-Mai; Lloyd, David; Riek, Stephan; O'Sullivan, John D.; Coulthard, Alan; Wong, Andrew

    2011-01-01

    Low frequency Repetitive Transcranial Magnetic Stimulation (rTMS) has previously been applied to language homologues in non-fluent populations of persons with aphasia yielding significant improvements in behavioral language function up to 43 months post stimulation. The present study aimed to investigate the electrophysiological correlates…

  15. Performance Characterization of an Actively Cooled Repetitive Transcranial Magnetic Stimulation Coil for the Rat.

    PubMed

    Parthoens, Joke; Verhaeghe, Jeroen; Servaes, Stijn; Miranda, Alan; Stroobants, Sigrid; Staelens, Steven

    2016-07-01

    This study characterizes and validates a recently developed dedicated circular rat coil for small animal repetitive Transcranial Magnetic Stimulation (rTMS). The electric (E) field distribution was calculated in a three-dimensional (3D) spherical rat head model and coil cooling performance was characterized. Motor threshold (MT) in rats (n = 12) was determined using two current directions, MT variability (n = 16) and laterality (n = 11) of the stimulation was assessed. Finally, 2-deoxy-2-((18) F)fluoro-D-glucose ([(18) F]-FDG) small animal Positron Emission Tomography (µPET) after sham and 1, 10, and 50 Hz rTMS stimulation (n = 9) with the new Cool-40 Rat Coil (MagVenture, Denmark) was performed. The coil could produce high E-fields of maximum 220 V/m and more than 100 V/m at depths up to 5.3 mm in a ring-shaped distribution. No lateralization of stimulation was observed. Independent of the current direction, reproducible MT measurements were obtained at low percentages (27 ± 6%) of the maximum machine output (MO, MagPro X100 [MagVenture, Denmark]). At this intensity, rTMS with long pulse trains is feasible (1 Hz: continuous stimulation; 5 Hz: 1000 pulses; 10 Hz and 50 Hz: 272 pulses). When compared to sham, rTMS at different frequencies induced decreases in [(18) F]-FDG-uptake bilaterally mainly in dorsal cortical regions (visual, retrosplenial, and somatosensory cortices) and increases mainly in ventral regions (entorhinal cortex and amygdala). The coil is suitable for rTMS in rats and achieves unprecedented high E-fields at high stimulation frequencies and long durations with however a rather unfocal rat brain stimulation. Reproducible MEPs as well as alterations in cerebral glucose metabolism following rTMS were demonstrated. © 2016 International Neuromodulation Society.

  16. Effects of low-frequency repetitive transcranial magnetic stimulation on event-related potential P300

    NASA Astrophysics Data System (ADS)

    Torii, Tetsuya; Sato, Aya; Iwahashi, Masakuni; Iramina, Keiji

    2012-04-01

    The present study analyzed the effects of repetitive transcranial magnetic stimulation (rTMS) on brain activity. P300 latency of event-related potential (ERP) was used to evaluate the effects of low-frequency and short-term rTMS by stimulating the supramarginal gyrus (SMG), which is considered to be the related area of P300 origin. In addition, the prolonged stimulation effects on P300 latency were analyzed after applying rTMS. A figure-eight coil was used to stimulate left-right SMG, and intensity of magnetic stimulation was 80% of motor threshold. A total of 100 magnetic pulses were applied for rTMS. The effects of stimulus frequency at 0.5 or 1 Hz were determined. Following rTMS, an odd-ball task was performed and P300 latency of ERP was measured. The odd-ball task was performed at 5, 10, and 15 min post-rTMS. ERP was measured prior to magnetic stimulation as a control. Electroencephalograph (EEG) was measured at Fz, Cz, and Pz that were indicated by the international 10-20 electrode system. Results demonstrated that different effects on P300 latency occurred between 0.5-1 Hz rTMS. With 1 Hz low-frequency magnetic stimulation to the left SMG, P300 latency decreased. Compared to the control, the latency time difference was approximately 15 ms at Cz. This decrease continued for approximately 10 min post-rTMS. In contrast, 0.5 Hz rTMS resulted in delayed P300 latency. Compared to the control, the latency time difference was approximately 20 ms at Fz, and this delayed effect continued for approximately 15 min post-rTMS. Results demonstrated that P300 latency varied according to rTMS frequency. Furthermore, the duration of the effect was not similar for stimulus frequency of low-frequency rTMS.

  17. [Clinical Introduction of Repetitive Transcranial Magnetic Stimulation for Major Depression in Japan].

    PubMed

    Nakamura, Motoaki

    2015-01-01

    Therapeutic applications of repetitive transcranial magnetic stimulation (rTMS) have long been awaited for not only neurological but also psychiatric disorders as a low-invasive transcranial brain stimulation. In 2008, the Food and Drug Administration (FDA) of the United States finally approved repetitive transcranial magnetic stimulation (rTMS) for medication-resistant patients with major depression. More recently, at the beginning of 2013, a deep TMS device with the H-coil received FDA approval as the second TMS device for major depression. In Japan, it is estimated that more than 200,000 patients with medication-resistant major depression could be candidates for rTMS treatment. To promote the clinical introduction of rTMS for major depression, joint discussion has been ongoing including the Japanese Society of Psychiatry and Neurology (JSPN), the Japanese Ministry of Health, Labour, and Welfare (MHLW), and the Pharmaceutical and Medical Devices Agency (PMDA). On the other hand, some corporate efforts have begun to get MHLW/PMDA approval for a few types of rTMS device. In 2013, the JSPN established a new committee in order to discuss the introduction of neuromodulation methods such as rTMS in Japan. The committee has been discussing how rTMS should be introduced appropriately with expedition, considering the MHLW regulations for the expedited introduction or provisional use of advanced medical technology. Also, the MHLW has required related psychiatric societies to formulate clinical guidelines of rTMS for major depression in order to avoid any potential overuse or misuse. A number of controversies are ongoing, such as standards for the appropriate clinical application of rTMS, a suitable position of rTMS within the comprehensive treatment algorithm of major depression, and bioethical standards for brain stimulation (neuroethics). Moreover, there are some pragmatic issues. For instance, the Japanese Society of Clinical Neurophysiology (JSCN) has restricted

  18. Modulation of EEG Functional Connectivity Networks in Subjects Undergoing Repetitive Transcranial Magnetic Stimulation

    PubMed Central

    Shafi, Mouhsin M.; Westover, M. Brandon; Oberman, Lindsay; Cash, Sydney S.; Pascual-Leone, Alvaro

    2014-01-01

    Transcranial magnetic stimulation (TMS) is a noninvasive brain stimulation technique that utilizes magnetic fluxes to alter cortical activity. Continuous theta-burst repetitive TMS (cTBS) results in long-lasting decreases in indices of cortical excitability, and alterations in performance of behavioral tasks. We investigated the effects of cTBS on cortical function via functional connectivity and graph theoretical analysis of EEG data. Thirty-one channel resting-state EEG recordings were obtained before and after 40 s of cTBS stimulation to the left primary motor cortex. Functional connectivity between nodes was assessed in multiple frequency bands using lagged max-covariance, and subsequently thresholded to construct undirected graphs. After cTBS, we find widespread decreases in functional connectivity in the alpha band. There are also simultaneous increases in functional connectivity in the high-beta bands, especially amongst anterior and interhemispheric connections. The analysis of the undirected graphs reveals that interhemispheric and interregional connections are more likely to be modulated after cTBS than local connections. There is also a shift in the topology of network connectivity, with an increase in the clustering coefficient after cTBS in the beta bands, and a decrease in clustering and increase in path length in the alpha band, with the alpha-band connectivity primarily decreased near the site of stimulation. cTBS produces widespread alterations in cortical functional connectivity, with resulting shifts in cortical network topology. PMID:23471637

  19. Prefrontal and parietal cortex in human episodic memory: an interference study by repetitive transcranial magnetic stimulation.

    PubMed

    Rossi, Simone; Pasqualetti, Patrizio; Zito, Giancarlo; Vecchio, Fabrizio; Cappa, Stefano F; Miniussi, Carlo; Babiloni, Claudio; Rossini, Paolo M

    2006-02-01

    Neuroimaging findings, including repetitive transcranial magnetic stimulation (rTMS) interference, point to an engagement of prefrontal cortex (PFC) in learning and memory. Whether parietal cortex (PC) activity is causally linked to successful episodic encoding and retrieval is still uncertain. We compared the effects of event-related active or sham rTMS (a rapid-rate train coincident to the very first phases of memoranda presentation) to the left or right intraparietal sulcus, during a standardized episodic memory task of visual scenes, with those obtained in a fully matched sample of subjects who received rTMS on left or right dorsolateral PFC during the same task. In these subjects, specific hemispheric effects of rTMS included interference with encoding after left stimulation and disruption of retrieval after right stimulation. The interference of PC-rTMS on encoding/retrieval performance was negligible, lacking specificity even when higher intensities of stimulation were applied. However, right PC-rTMS of the same intensity lengthened reaction times in the context of a purely attentive visuospatial task. These results suggest that the activity of intraparietal sulci shown in several functional magnetic resonance studies on memory, unlike that of the dorsolateral PFC, is not causally engaged to a useful degree in memory encoding and retrieval of visual scenes. The parietal activations accompanying the memorization processes could reflect the engagement of a widespread brain attentional network, in which interference on a single 'node' is insufficient for an overt disruption of memory performance.

  20. Repetitive transcranial magnetic stimulation induces long-lasting changes in protein expression and histone acetylation

    PubMed Central

    Etiévant, Adeline; Manta, Stella; Latapy, Camille; Magno, Luiz Alexandre V.; Fecteau, Shirley; Beaulieu, Jean-Martin

    2015-01-01

    The use of non-invasive brain stimulation like repetitive transcranial magnetic stimulation (rTMS) is an increasingly popular set of methods with promising results for the treatment of neurological and psychiatric disorders. Despite great enthusiasm, the impact of non-invasive brain stimulation on its neuronal substrates remains largely unknown. Here we show that rTMS applied over the frontal cortex of awaken mice induces dopamine D2 receptor dependent persistent changes of CDK5 and PSD-95 protein levels specifically within the stimulated brain area. Importantly, these modifications were associated with changes of histone acetylation at the promoter of these genes and prevented by administration of the histone deacetylase inhibitor MS-275. These findings show that, like several other psychoactive treatments, repeated rTMS sessions can exert long-lasting effects on neuronal substrates. This underscores the need of understanding these effects in the development of future clinical applications as well as in the establishment of improved guidelines to use rTMS in non-medical settings. PMID:26585834

  1. Treating Clinical Depression with Repetitive Deep Transcranial Magnetic Stimulation Using the Brainsway H1-coil

    PubMed Central

    Feifel, David; Pappas, Katherine

    2016-01-01

    Repetitive transcranial magnetic stimulation (rTMS) is an emerging non-pharmacological approach to treating many brain-based disorders. rTMS uses electromagnetic coils to stimulate areas of the brain non-invasively. Deep transcranial magnetic stimulation (dTMS) with the Brainsway H1-coil system specifically is a type of rTMS indicated for treating patients with major depressive disorder (MDD) who are resistant to medication. The unique H1-coil design of this device is able to stimulate neuronal pathways that lie deeper in the targeted brain areas than those reached by conventional rTMS coils. dTMS is considered to be low-risk and well tolerated, making it a viable treatment option for people who have not responded to medication or psychotherapy trials for their depression. Randomized, sham-control studies have demonstrated that dTMS produces significantly greater improvement in depressive symptoms than sham dTMS treatment in patients with major depression that has not responded to antidepressant medication. In this paper, we will review the methodology for treating major depression with dTMS using an H1-coil. PMID:27768049

  2. Pressure pain thresholds increase after preconditioning 1 Hz repetitive transcranial magnetic stimulation with transcranial direct current stimulation.

    PubMed

    Moloney, Tonya M; Witney, Alice G

    2014-01-01

    The primary motor cortex (M1) is an effective target of non-invasive cortical stimulation (NICS) for pain threshold modulation. It has been suggested that the initial level of cortical excitability of M1 plays a key role in the plastic effects of NICS. Here we investigate whether transcranial direct current stimulation (tDCS) primed 1 Hz repetitive transcranial magnetic stimulation (rTMS) modulates experimental pressure pain thresholds and if this is related to observed alterations in cortical excitability. 15 healthy, male participants received 10 min 1 mA anodal, cathodal and sham tDCS to the left M1 before 15 min 1 Hz rTMS in separate sessions over a period of 3 weeks. Motor cortical excitability was recorded at baseline, post-tDCS priming and post-rTMS through recording motor evoked potentials (MEPs) from right FDI muscle. Pressure pain thresholds were determined by quantitative sensory testing (QST) through a computerized algometer, on the palmar thenar of the right hand pre- and post-stimulation. Cathodal tDCS-primed 1 Hz-rTMS was found to reverse the expected suppressive effect of 1 Hz rTMS on cortical excitability; leading to an overall increase in activity (p<0.001) with a parallel increase in pressure pain thresholds (p<0.01). In contrast, anodal tDCS-primed 1 Hz-rTMS resulted in a corresponding decrease in cortical excitability (p<0.05), with no significant effect on pressure pain. This study demonstrates that priming the M1 before stimulation of 1 Hz-rTMS modulates experimental pressure pain thresholds in a safe and controlled manner, producing a form of analgesia.

  3. Repetitive nerve stimulation decreases the acetylcholine content of quanta at the frog neuromuscular junction.

    PubMed

    Naves, L A; Van der Kloot, W

    2001-05-01

    We investigated how elevated quantal release produced by motor nerve stimulation affects the size of the quanta. The motor nerve was stimulated at 10 Hz in preparations in which excitation-contraction coupling was disrupted. Two hundred stimuli reduced the size of the time integrals of the miniature endplate currents ([integral]MEPCs), measured at the same junction immediately after stimulation, by 16 %. Three thousand stimuli reduced size by 23 %. When the solution contained 10 microM neostigmine (NEO) 3000 stimuli reduced [integral]MEPCs by 60 %, because with acetylcholinesterase (AChE) inhibited, [integral]MEPC size is more sensitive to changes in acetylcholine (ACh) content. Similar decreases in miniature endplate potential size ([integral]MEPP) followed repetitive stimulation of contracting preparations. The depolarization produced by iontophoretic pulses of ACh was scarcely changed by 3000 nerve stimuli at 10 Hz, suggesting that the decreases in miniature sizes are largely due to less ACh released per quantum. Following 3000 stimuli at 10 Hz the sizes of the [integral]MEPCs increased back to pre-stimulus values with a half-time of 8-10 min. Recovery was blocked by (-)-vesamicol (VES), by hemicholinium-3 (HC3) and by nicotinic cholinergic agonists - all of which inhibit ACh loading into synaptic vesicles. The number of quanta in the total store was estimated by releasing them with carbonyl cyanide m-chlorophenylhydrazone (CCCP). CCCP releases fewer quanta after stimulation than from unstimulated controls. After resting for hours following stimulation, the releasable number increased, even when ACh loading inhibitors were present. We conclude that the inhibitors do not block a significant fraction of the ACh loading into reformed reserve vesicles and propose that ACh can be loaded in a series of steps.

  4. High-Frequency Repetitive Transcranial Magnetic Stimulation Reduces Pain in Postherpetic Neuralgia.

    PubMed

    Ma, Shu-Min; Ni, Jia-Xiang; Li, Xuan-Ying; Yang, Li-Qiang; Guo, Yu-Na; Tang, Yuan-Zhang

    2015-11-01

    Postherpetic neuralgia (PHN) is one of the most intractable pain disorders, especially in elderly patients. There is evidence that repetitive transcranial magnetic stimulation (rTMS) reduces neuropathic pain; however, its effectiveness for PHN is unknown. This study investigated the efficacy of high-frequency rTMS in patients with PHN. A total of 40 patients were randomly assigned to receive 10 sessions of real or sham rTMS of the primary motor cortex. Each stimulation session consisted of a series of 300 five-second pulses with a frequency of 10 Hz and an interval of 3 seconds between each train, giving a total of 1500 pulses per session. The primary outcome was pain intensity measured before stimulation from first intervention (T0) to the final stimulation (T10), and 1 and 3 months after final stimulation (T11 and T12). Other outcomes measured included scores on the short form McGill pain questionnaire, self-rating depression scale, quality of life (QOL), sleep quality, the patient global impression of change, medication regulation, and reported adverse events. The real rTMS group demonstrated greater reduction of visual analogue scale (VAS) than the sham group at each time point except for T0 (P = 0.399) and T1 (P = 0.091). Mean VAS reduction in the real rTMS group was 16.89% for duration of disease longer than 6 months. These analgesic effects were associated with long-term improvement in rating-scale items related to QOL. The results suggest that rTMS is an effective and safe therapy in patients with PHN. Wiley Periodicals, Inc.

  5. Repetitive common peroneal nerve stimulation increases ankle dorsiflexor motor evoked potentials in incomplete spinal cord lesions.

    PubMed

    Thompson, Aiko K; Lapallo, Brandon; Duffield, Michael; Abel, Briana M; Pomerantz, Ferne

    2011-04-01

    Plasticity of corticospinal tract (CST) activity likely plays a key role in motor function recovery after central nervous system (CNS) lesions. In non-injured adults, 30 min of repetitive common peroneal nerve stimulation (rCPnS) increases CST excitability by 40-50% and the effect persists for at least 30 min. The present study evaluated with transcranial magnetic stimulation (TMS) the changes in CST excitability after 30 min of rCPnS in people with foot drop due to incomplete SCI. Suprathreshold rCPnS (25 Hz, alternating 1 s on 1 s off stimulation cycle) was given for two 15-min periods, while the subject sat at rest with ankle and knee joints fixed. Before, between, and after the periods of stimulation, the tibialis anterior (TA) motor evoked potentials (MEPs) to TMS were measured at a TMS intensity that originally produced a half-maximum MEP (typically 10-20% above threshold) while the sitting subject provided 25-30% maximum voluntary TA contraction. In 10 subjects with SCI, the peak-to-peak TA MEP increased by 14 ± 3% after rCPnS and the peak increase (+21 ± 7%) occurred 15 min after the cessation of rCPnS. The TA H-reflex, measured in separate experiments in 7 subjects, did not increase after rCPnS. The results indicate that rCPnS can increase CST excitability for the TA in people with incomplete SCI, although its effects appear smaller and shorter lasting than those found in non-injured control subjects. Such short-term plasticity in the CST excitability induced by rCPnS may contribute to long-term therapeutic effects of functional electrical stimulation previously reported in people with CNS lesions.

  6. Neuronavigated vs. conventional repetitive transcranial magnetic stimulation method for virtual lesioning on the Broca's area.

    PubMed

    Kim, Woo Jin; Min, Yu Sun; Yang, Eun Joo; Paik, Nam-Jong

    2014-01-01

    This study was undertaken to test the hypothesis that repetitive transcranial magnetic stimulation (rTMS) using a neuronavigational TMS system (nTMS) to the Broca's area would elicit greater virtual aphasia than rTMS using the conventional TMS method (cTMS). Eighteen healthy subjects underwent a randomized crossover experiment to induce virtual aphasia by targeting the Brodmann area 44 and 45 for nTMS, and F3 of international 10-20 system for cTMS. Reaction time for a picture naming task and the reaction duration for a six-digit number naming task were measured before and after each session of stimulation, and compared between the cTMS and nTMS. The stability of the coil positioning on the target was measured by depicting the variability of talairach coordinates (x, y, z) of the sampled stimulation localizations. At baseline, outcome variables were comparable between cTMS and nTMS. nTMS induced significant delays in reaction time from 944.0 ± 203.4 msec to 1304.6 ± 215.7 msec (p < 0.001) and reaction duration from 1780.5 ± 286.8 msec to 1914.9 ± 295.6 msec (p < 0.001) compared with baseline, whereas cTMS showed no significant changes (p = 0.959 and p = 0.179, respectively). The mean talairach space coordinates of nTMS demonstrated greater consistency of localization of stimulation with the target, and the error range relative to the target was narrower for the nTMS compared with the cTMS (p < 0.001). nTMS leads to more robust neuromodulation of Broca's area, resulting in delayed verbal reaction time as well as more accurate targeting of the intended stimulation location, demonstrating superiority of nTMS over cTMS for therapeutic use of rTMS in neurorehabilitation. © 2013 International Neuromodulation Society.

  7. Lateralized effects of prefrontal repetitive transcranial magnetic stimulation on emotional working memory.

    PubMed

    Weigand, Anne; Grimm, Simone; Astalosch, Antje; Guo, Jia Shen; Briesemeister, Benny B; Lisanby, Sarah H; Luber, Bruce; Bajbouj, Malek

    2013-05-01

    Little is known about the neural correlates underlying the integration of working memory and emotion processing. We investigated the effects of low-frequency repetitive transcranial magnetic stimulation (rTMS) applied over the left or right dorsolateral prefrontal cortex (DLPFC) on emotional working memory. In a sham-controlled crossover design, participants performed an emotional 3-back task (EMOBACK) at baseline and after stimulation (1 Hz, 15 min, 110 % of the resting motor threshold) in two subsequent sessions. Stimuli were words assigned to the distinct emotion categories fear and anger as well as neutral words. We found lateralized rTMS effects in the EMOBACK task accuracy for fear-related words, with enhanced performance after rTMS applied over the right DLPFC and impaired performance after rTMS applied over the left DLPFC. No significant stimulation effect could be found for anger-related and neutral words. Our findings are the first to demonstrate a causal role of the right DLPFC in working memory for negative, withdrawal-related words and provide further support for a hemispheric lateralization of emotion processing.

  8. Repetitive electric stimulation elicits enduring improvement of sensorimotor performance in seniors.

    PubMed

    Kalisch, Tobias; Tegenthoff, Martin; Dinse, Hubert R

    2010-01-01

    Age-related changes occur on all stages of the human somatosensory pathway, thereby deteriorating tactile, haptic, and sensorimotor performance. However, recent studies show that age-related changes are not irreversible but treatable through peripheral stimulation paradigms based on neuroplasticity mechanisms. We here applied repetitive electric stimulation (rES) to the fingers on a bi-weekly basis for 4 weeks to induce enduring amelioration of age-related changes in healthy individuals aged 60-85 years. Tactile, haptic, and motor performance gradually improved over time of intervention. After termination of rES, tactile acuity recovered to baseline within 2 weeks, while the gains in haptic and motor performance were preserved for 2 weeks. Sham stimulation showed no comparable changes. Our data indicate that age-related decline of sensorimotor performance can be ameliorated by rES and can be stabilized by the repeated application. Thus, long-term application of rES appears as a prime candidate for maintaining sensorimotor functions in elderly individuals.

  9. Repetitive Transcranial Magnetic Stimulation (rTMS)-Induced Trigeminal Autonomic Cephalalgia

    PubMed Central

    DURMAZ, Onur; ATEŞ, Mehmet Alpay; ŞENOL, Mehmet Güney

    2015-01-01

    Repetitive transcranial magnetic stimulation (rTMS) is an effective and novel treatment method that has been approved for the treatment of refractory depression by the U.S. Food and Drug Administration. The most common side effects of rTMS are a transient headache that usually responds to simple analgesics, local discomfort in the stimulation area, dizziness, ipsilateral lacrimation and, very rarely, generalized seizure. TMS is also regarded as a beneficial tool for investigating mechanisms underlying headache. Although rTMS has considerable benefits in terms of headache, there is the potential for rare side effects. In this report, we present the case of a patient with no history of autonomic headache who underwent a course of rTMS for refractory unipolar depression caused by an inadequate response to pharmacotherapy. After his fourth rTMS session, the patient developed sudden headaches with characteristics of trigeminal autonomic cephalalgia on the stimulated side, representing a noteworthy example of the potential side effects of rTMS. PMID:28360729

  10. Theta-burst repetitive transcranial magnetic stimulation suppresses specific excitatory circuits in the human motor cortex

    PubMed Central

    Di Lazzaro, V; Pilato, F; Saturno, E; Oliviero, A; Dileone, M; Mazzone, P; Insola, A; Tonali, PA; Ranieri, F; Huang, YZ; Rothwell, JC

    2005-01-01

    In four conscious patients who had electrodes implanted in the cervical epidural space for the control of pain, we recorded corticospinal volleys evoked by single-pulse transcranial magnetic stimulation (TMS) over the motor cortex before and after a 20 s period of continuous theta-burst stimulation (cTBS). It has previously been reported that this form of repetitive TMS reduces the amplitude of motor-evoked potentials (MEPs), with the maximum effect occurring at 5–10 min after the end of stimulation. The present results show that cTBS preferentially decreases the amplitude of the corticospinal I1 wave, with approximately the same time course. This is consistent with a cortical origin of the effect on the MEP. However, other protocols that lead to MEP suppression, such as short-interval intracortical inhibition, are characterized by reduced excitability of late I waves (particularly I3), suggesting that cTBS suppresses MEPs through different mechanisms, such as long-term depression in excitatory synaptic connections. PMID:15845575

  11. Repetitive Electric Stimulation Elicits Enduring Improvement of Sensorimotor Performance in Seniors

    PubMed Central

    Kalisch, Tobias; Tegenthoff, Martin; Dinse, Hubert R.

    2010-01-01

    Age-related changes occur on all stages of the human somatosensory pathway, thereby deteriorating tactile, haptic, and sensorimotor performance. However, recent studies show that age-related changes are not irreversible but treatable through peripheral stimulation paradigms based on neuroplasticity mechanisms. We here applied repetitive electric stimulation (rES) to the fingers on a bi-weekly basis for 4 weeks to induce enduring amelioration of age-related changes in healthy individuals aged 60–85 years. Tactile, haptic, and motor performance gradually improved over time of intervention. After termination of rES, tactile acuity recovered to baseline within 2 weeks, while the gains in haptic and motor performance were preserved for 2 weeks. Sham stimulation showed no comparable changes. Our data indicate that age-related decline of sensorimotor performance can be ameliorated by rES and can be stabilized by the repeated application. Thus, long-term application of rES appears as a prime candidate for maintaining sensorimotor functions in elderly individuals. PMID:20414332

  12. Enhanced accuracy in novel mirror drawing after repetitive transcranial magnetic stimulation-induced proprioceptive deafferentation.

    PubMed

    Balslev, Daniela; Christensen, Lars O D; Lee, Ji-Hang; Law, Ian; Paulson, Olaf B; Miall, R Christopher

    2004-10-27

    When performing visually guided actions under conditions of perturbed visual feedback, e.g., in a mirror or a video camera, there is a spatial conflict between visual and proprioceptive information. Recent studies have shown that subjects without proprioception avoid this conflict and show a performance benefit. In this study, we tested whether deafferentation induced by repetitive transcranial magnetic stimulation (rTMS) can improve mirror tracing skills in normal subjects. Hand trajectory error during novel mirror drawing was compared across two groups of subjects that received either 1 Hz rTMS over the somatosensory cortex contralateral to the hand or sham stimulation. Mirror tracing was more accurate after rTMS than after sham stimulation. Using a position-matching task, we confirmed that rTMS reduced proprioceptive acuity and that this reduction was largest when the coil was placed at an anterior parietal site. It is thus possible, with rTMS, to enhance motor performance in tasks involving a visuoproprioceptive conflict, presumably by reducing the excitability of somatosensory cortical areas that contribute to the sense of hand position.

  13. Theta-burst repetitive transcranial magnetic stimulation suppresses specific excitatory circuits in the human motor cortex.

    PubMed

    Di Lazzaro, V; Pilato, F; Saturno, E; Oliviero, A; Dileone, M; Mazzone, P; Insola, A; Tonali, P A; Ranieri, F; Huang, Y Z; Rothwell, J C

    2005-06-15

    In four conscious patients who had electrodes implanted in the cervical epidural space for the control of pain, we recorded corticospinal volleys evoked by single-pulse transcranial magnetic stimulation (TMS) over the motor cortex before and after a 20 s period of continuous theta-burst stimulation (cTBS). It has previously been reported that this form of repetitive TMS reduces the amplitude of motor-evoked potentials (MEPs), with the maximum effect occurring at 5-10 min after the end of stimulation. The present results show that cTBS preferentially decreases the amplitude of the corticospinal I1 wave, with approximately the same time course. This is consistent with a cortical origin of the effect on the MEP. However, other protocols that lead to MEP suppression, such as short-interval intracortical inhibition, are characterized by reduced excitability of late I waves (particularly I3), suggesting that cTBS suppresses MEPs through different mechanisms, such as long-term depression in excitatory synaptic connections.

  14. Transcranial magnetic stimulation (TMS)/repetitive TMS in mild cognitive impairment and Alzheimer's disease.

    PubMed

    Nardone, R; Tezzon, F; Höller, Y; Golaszewski, S; Trinka, E; Brigo, F

    2014-06-01

    Several Transcranial Magnetic Stimulation (TMS) techniques can be applied to noninvasively measure cortical excitability and brain plasticity in humans. TMS has been used to assess neuroplastic changes in Alzheimer's disease (AD), corroborating findings that cortical physiology is altered in AD due to the underlying neurodegenerative process. In fact, many TMS studies have provided physiological evidence of abnormalities in cortical excitability, connectivity, and plasticity in patients with AD. Moreover, the combination of TMS with other neurophysiological techniques, such as high-density electroencephalography (EEG), makes it possible to study local and network cortical plasticity directly. Interestingly, several TMS studies revealed abnormalities in patients with early AD and even with mild cognitive impairment (MCI), thus enabling early identification of subjects in whom the cholinergic degeneration has occurred. Furthermore, TMS can influence brain function if delivered repetitively; repetitive TMS (rTMS) is capable of modulating cortical excitability and inducing long-lasting neuroplastic changes. Preliminary findings have suggested that rTMS can enhance performances on several cognitive functions impaired in AD and MCI. However, further well-controlled studies with appropriate methodology in larger patient cohorts are needed to replicate and extend the initial findings. The purpose of this paper was to provide an updated and comprehensive systematic review of the studies that have employed TMS/rTMS in patients with MCI and AD. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. History, Studies and Specific Uses of Repetitive Transcranial Magnetic Stimulation (rTMS) in Treating Epilepsy

    PubMed Central

    NOOHI, Sima; AMIRSALARI, Susan

    2016-01-01

    Objective In this study, repetitive Transcranial Magnetic Stimulation (rTMS) and its specific use for treating epilepsy were carefully scrutinized. Materials & Methods Target researches such as review articles, case reports, books and theses, which had to do with therapeutic method of rTMS were surveyed. It is worth mentioning that until the final stages, the search for records and documents related to rTMS went on and in the end, the collected data underwent a qualitative analysis. Results As the literature review suggests, TMS principally applies electromagnetic induction to generate an electric current inside the brain without physical contact. The therapeutic uses of rTMS are for a wide range of mental disorders, namely epilepsy, chronic pains, motor disorders and so on. Conclusion Despite safety concerns and possible side effects, many researchers subscribe to rTMS and see a bright future for it. PMID:27057180

  16. Local GABA Concentration Predicts Perceptual Improvements After Repetitive Sensory Stimulation in Humans.

    PubMed

    Heba, Stefanie; Puts, Nicolaas A J; Kalisch, Tobias; Glaubitz, Benjamin; Haag, Lauren M; Lenz, Melanie; Dinse, Hubert R; Edden, Richard A E; Tegenthoff, Martin; Schmidt-Wilcke, Tobias

    2016-03-01

    Learning mechanisms are based on synaptic plasticity processes. Numerous studies on synaptic plasticity suggest that the regulation of the inhibitory neurotransmitter γ-aminobutyric acid (GABA) plays a central role maintaining the delicate balance of inhibition and excitation. However, in humans, a link between learning outcome and GABA levels has not been shown so far. Using magnetic resonance spectroscopy of GABA prior to and after repetitive tactile stimulation, we show here that baseline GABA+ levels predict changes in perceptual outcome. Although no net changes in GABA+ are observed, the GABA+ concentration prior to intervention explains almost 60% of the variance in learning outcome. Our data suggest that behavioral effects can be predicted by baseline GABA+ levels, which provide new insights into the role of inhibitory mechanisms during perceptual learning.

  17. High-frequency repetitive transcranial magnetic stimulation delays rapid eye movement sleep.

    PubMed

    Cohrs, S; Tergau, F; Riech, S; Kastner, S; Paulus, W; Ziemann, U; Rüther, E; Hajak, G

    1998-10-26

    Repetitive transcranial magnetic stimulation (rTMS) is a promising new treatment for patients with major depression. However, the mechanisms underlying the antidepressive action of rTMS are widely unclear. Rapid eye movement (REM) sleep has been shown to play an important role in the pathophysiology of depression. In the present study we demonstrate that rTMS delays the first REM sleep epoch on average by 17 min (102.6 +/-22.5 min vs 85.7+/-18.8 min; p < 0.02) and prolongs the nonREM-REM cycle length (109.1+/-11.4 min vs 101.8+/-13.2min, p< 0.012). These rTMS-induced changes in REM sleep variables correspond to findings observed after pharmacological and electroconvulsive treatment of depression. Therefore, it is likely that the capability of rTMS to affect circadian and ultradian biological rhythms contributes to its antidepressive action.

  18. Repetitive transcranial magnetic stimulation to treat substance use disorders and compulsive behavior.

    PubMed

    Protasio, Maria I B; da Silva, João P L; Arias-Carrión, Oscar; Nardi, Antonio E; Machado, Sergio; Cruz, Marcelo S

    2015-01-01

    Compulsions, like pathological gambling, binge-eating disorder, alcohol, tobacco or cocaine abuse and compulsive shopping have similar neurophysiological processing. This study aimed to examine the efficacy of repetitive transcranial magnetic stimulation (rTMS) in improving patient control over compulsive behavior. The rTMS modulatory role in cortical mesolimbic pathways possibly implies improvement of the inhibitory control system and compulsive consumption drive. Thus, craving reduction would be a component for control achievement. Within this context, 17 studies were found. Most studies applied rTMS over the left dorsolateral prefrontal cortex. Craving reduction was observed in 10 studies and was associated with improved control of compulsion in two of them. In one study reduction in consumption was found without reduction in craving. In addition, improvement in decision making was found in one study.

  19. Repetitive transcranial magnetic stimulation of human MT+ reduces apparent motion perception.

    PubMed

    Matsuyoshi, Daisuke; Hirose, Nobuyuki; Mima, Tatsuya; Fukuyama, Hidenao; Osaka, Naoyuki

    2007-12-18

    We investigated the effects of repetitive transcranial magnetic stimulation (rTMS) over the human cerebral cortex on apparent motion perception. Previous studies have shown that human extrastriate visual area MT+ (V5) processes not only real but also apparent motion. However, the functional relevance of MT+ on long-range apparent motion perception remains unclear. Here, we show direct evidence for the involvement of MT+ in apparent motion perception using rTMS, which is known to temporarily inhibit a localized region in the cerebral cortex. The results showed that apparent motion perception decreased after applying rTMS over MT+, but not after applying rTMS over the control region (inferior temporal gyrus). The decrease in performance caused by applying rTMS to MT+ suggests that MT+ is a causally responsible region for apparent motion perception, and thus, further supports the idea that MT+ plays a major role in the perception of motion.

  20. Repetitive transcranial magnetic stimulation therapy for post-stroke non-fluent aphasia: A critical review.

    PubMed

    Kapoor, Arunima

    2017-05-26

    To assess the efficacy of repetitive transcranial magnetic stimulation for post-stroke non-fluent aphasia through a review of current literature. Three electronic databases (Medline, Embase & Scopus) were searched for articles. Relevant studies were further evaluated and studies that met inclusion criteria were reviewed. The literature search yielded 4713 studies. Thirty-five articles were further evaluated to be included. Thirteen met all inclusion criteria and were chosen for review. The studies provide moderate to strong evidence that rTMS may be an effective treatment for non-fluent stroke aphasia. There are some strong studies evaluating the efficacy of rTMS in non-fluent stroke patients but further research is required to fully establish the usefulness of this treatment. Future directions and limitations are presented.

  1. Effects of Bilateral Repetitive Transcranial Magnetic Stimulation on Post-Stroke Dysphagia.

    PubMed

    Park, Eunhee; Kim, Min Su; Chang, Won Hyuk; Oh, Su Mi; Kim, Yun Kwan; Lee, Ahee; Kim, Yun-Hee

    Optimal protocol of repetitive transcranial magnetic stimulation (rTMS) on post-stroke dysphagia remains uncertain with regard to its clinical efficacy. The aim of the present study is to investigate the effects of high-frequency rTMS at the bilateral motor cortices over the cortical representation of the mylohyoid muscles in the patients with post-stroke dysphagia. This study was a single-blind, randomized controlled study with a blinded observer. Thirty-five stroke patients were randomly divided into three intervention groups: the bilateral stimulation group, the unilateral stimulation group, and the sham stimulation group. For the bilateral stimulation group, 500 pulses of 10 Hz rTMS over the ipsilesional and 500 pulses of 10 Hz rTMS over the contralesional motor cortices over the cortical areas that project to the mylohyoid muscles were administered daily for 2 consecutive weeks. For the unilateral stimulation group, 500 pulses of 10 Hz rTMS over the ipsilesional motor cortex over the cortical representation of the mylohyoid muscle and the same amount of sham rTMS over the contralesional hemisphere were applied. For the sham stimulation group, sham rTMS was applied at the bilateral motor cortices. Clinical swallowing function and videofluoroscopic swallowing studies were assessed before the intervention (T0), immediately after the intervention (T1) and 3 weeks after the intervention (T2) using Clinical Dysphagia Scale (CDS), Dysphagia Outcome and Severity Scale (DOSS), Penetration Aspiration Scale (PAS), and Videofluoroscopic Dysphagia Scale (VDS). There were significant time and intervention interaction effects in the CDS, DOSS, PAS, and VDS scores (p < 0.05). In the direct comparison of the changes in the swallowing parameters among the three groups, the change in CDS scores at T1 and T2 showed a significantly higher improvement in the bilateral simulation group than in two other groups (p < 0.05). There was a significantly larger change in the

  2. Repetitive Noninvasive Brain Stimulation to Modulate Cognitive Functions in Schizophrenia: A Systematic Review of Primary and Secondary Outcomes.

    PubMed

    Hasan, Alkomiet; Strube, Wolfgang; Palm, Ulrich; Wobrock, Thomas

    2016-07-01

    Despite many years of research, there is still an urgent need for new therapeutic options for the treatment of cognitive deficits in schizophrenia. Noninvasive brain stimulation (NIBS) has been proposed to be such a novel add-on treatment option. The main objective of this review was to systematically evaluate the cognitive effects of repetitive NIBS in schizophrenia. As most studies have not been specifically designed to investigate cognition as primary outcome, we have focused on both, primary and secondary outcomes. The PubMed/MEDLINE database (1985-2015) was systematically searched for interventional studies investigating the effects of repetitive NIBS on schizophrenia symptoms. All interventional clinical trials using repetitive transcranial stimulation, transcranial theta burst stimulation, and transcranial direct current stimulation for the treatment of schizophrenia were extracted and analyzed with regard to cognitive measures as primary or secondary outcomes. Seventy-six full-text articles were assessed for eligibility of which 33 studies were included in the qualitative synthesis. Of these 33 studies, only 4 studies included cognition as primary outcome, whereas 29 studies included cognitive measures as secondary outcomes. A beneficial effect of frontal NIBS could not be clearly established. No evidence for a cognitive disruptive effect of NIBS (temporal lobe) in schizophrenia could be detected. Finally, a large heterogeneity between studies in terms of inclusion criteria, stimulation parameters, applied cognitive measures, and follow-up intervals was observed. This review provides the first systematic overview regarding cognitive effects of repetitive NIBS in schizophrenia.

  3. Test-retest assessment of cortical activation induced by repetitive transcranial magnetic stimulation with brain atlas-guided optical topography

    NASA Astrophysics Data System (ADS)

    Tian, Fenghua; Kozel, F. Andrew; Yennu, Amarnath; Croarkin, Paul E.; McClintock, Shawn M.; Mapes, Kimberly S.; Husain, Mustafa M.; Liu, Hanli

    2012-11-01

    Repetitive transcranial magnetic stimulation (rTMS) is a technology that stimulates neurons with rapidly changing magnetic pulses with demonstrated therapeutic applications for various neuropsychiatric disorders. Functional near-infrared spectroscopy (fNIRS) is a suitable tool to assess rTMS-evoked brain responses without interference from the magnetic or electric fields generated by the TMS coil. We have previously reported a channel-wise study of combined rTMS/fNIRS on the motor and prefrontal cortices, showing a robust decrease of oxygenated hemoglobin concentration (Δ[HbO2]) at the sites of 1-Hz rTMS and the contralateral brain regions. However, the reliability of this putative clinical tool is unknown. In this study, we develop a rapid optical topography approach to spatially characterize the rTMS-evoked hemodynamic responses on a standard brain atlas. A hemispherical approximation of the brain is employed to convert the three-dimensional topography on the complex brain surface to a two-dimensional topography in the spherical coordinate system. The test-retest reliability of the combined rTMS/fNIRS is assessed using repeated measurements performed two to three days apart. The results demonstrate that the Δ[HbO2] amplitudes have moderate-to-high reliability at the group level; and the spatial patterns of the topographic images have high reproducibility in size and a moderate degree of overlap at the individual level.

  4. Effects of Repetitive Transcranial Magnetic Stimulation on Behavioral Recovery during Early Stage of Traumatic Brain Injury in Rats.

    PubMed

    Yoon, Kyung Jae; Lee, Yong-Taek; Chung, Pil-Wook; Lee, Yun Kyung; Kim, Dae Yul; Chun, Min Ho

    2015-10-01

    Repetitive transcranial magnetic stimulation (rTMS) is a promising technique that modulates neural networks. However, there were few studies evaluating the effects of rTMS in traumatic brain injury (TBI). Herein, we assessed the effectiveness of rTMS on behavioral recovery and metabolic changes using brain magnetic resonance spectroscopy (MRS) in a rat model of TBI. We also evaluated the safety of rTMS by measuring brain swelling with brain magnetic resonance imaging (MRI). Twenty male Sprague-Dawley rats underwent lateral fluid percussion and were randomly assigned to the sham (n=10) or the rTMS (n=10) group. rTMS was applied on the fourth day after TBI and consisted of 10 daily sessions for 2 weeks with 10 Hz frequency (total pulses=3,000). Although the rTMS group showed an anti-apoptotic effect around the peri-lesional area, functional improvements were not significantly different between the two groups. Additionally, rTMS did not modulate brain metabolites in MRS, nor was there any change of brain lesion or edema after magnetic stimulation. These data suggest that rTMS did not have beneficial effects on motor recovery during early stages of TBI, although an anti-apoptosis was observed in the peri-lesional area.

  5. Repetitive transcranial magnetic stimulation (rTMS) improves facial affect recognition in schizophrenia.

    PubMed

    Wölwer, Wolfgang; Lowe, Agnes; Brinkmeyer, Jürgen; Streit, Marcus; Habakuck, Mareke; Agelink, Marcus W; Mobascher, Arian; Gaebel, Wolfgang; Cordes, Joachim

    2014-01-01

    Facial affect recognition, a basic building block of social cognition, is often impaired in schizophrenia. Poor facial affect recognition is closely related to poor functional outcome; however, neither social cognitive impairments nor functional outcome are sufficiently improved by antipsychotic drug treatment alone. Adjunctive repetitive transcranial magnetic stimulation (rTMS) has been shown to enhance cognitive functioning in both healthy individuals and in people with neuropsychiatric disorders and to ameliorate clinical symptoms in psychiatric disorders, but its effects on social cognitive impairments in schizophrenia have not yet been studied. Therefore, we evaluated the effects of sham-controlled rTMS on facial affect recognition in patients with chronic schizophrenia. Inpatients (N = 36) on stable antipsychotic treatment were randomly assigned to double-blind high-frequency (10 Hz) rTMS or sham stimulation for a total of ten sessions over two weeks. In the verum group, each session consisted of 10 000 stimuli (20 trains of 5 s) applied over the left dorsolateral prefrontal cortex at 110% of motor threshold. Facial affect recognition was assessed before (T0) and after (T1) the ten sessions. Facial affect recognition improved significantly more after rTMS (accuracy change: mean = 8.9%, SD = 6.0%) than after sham stimulation (mean = 1.6%, SD = 3.5; Cohen's d = 1.45). There was no correlation with clinical improvement. Our results indicate that prefrontal 10 Hz rTMS stimulation may help to ameliorate impaired facial affect recognition in schizophrenia. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Stroke recovery can be enhanced by using repetitive transcranial magnetic stimulation (rTMS).

    PubMed

    Lefaucheur, J-P

    2006-01-01

    Post-stroke recovery is based on plastic changes in the central nervous system that can compensate the loss of activity in affected brain regions. In particular, monohemispheric stroke is thought to result in disinhibition of the contralesional unaffected hemisphere. Neurorehabilitation programs improve function partly by enhancing cortical reorganization. Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive way of producing potent changes in cortical excitability. Therefore, the application of rTMS was recently proposed to promote functional recovery in stroke patients, owing to the induced neuroplasticity. This review discusses the first clinical results that were obtained by rTMS in patients with post-stroke motor deficit, visuospatial neglect, or aphasia. These results are promising and depend on the site and frequency of stimulation. In summary, functional recovery might be obtained either when rTMS is applied at low-frequency (around 1 Hz) over the disinhibited, unaffected hemisphere in order to restore defective inhibition or when rTMS is applied at high-frequency (5 Hz or more) over the affected hemisphere in order to reactivate hypoactive regions. The overall procedure remains to be optimized, in particular regarding the number of rTMS sessions and the time of rTMS application after stroke. Cortical stimulation is an exciting perspective for improving functional recovery from stroke. Transient application of non-invasive transcranial stimulation during the time of the rehabilitation process will be preferable to the temporary implantation of epidural cortical electrodes, as recently proposed. Therefore, in the future, acute or recent stroke might be a major indication of rTMS in neurological practice.

  7. Cutting edge: natural DNA repetitive extragenic sequences from gram-negative pathogens strongly stimulate TLR9.

    PubMed

    Magnusson, Mattias; Tobes, Raquel; Sancho, Jaime; Pareja, Eduardo

    2007-07-01

    Bacterial DNA exerts immunostimulatory effects on mammalian cells via the intracellular TLR9. Although broad analysis of TLR9-mediated immunostimulatory potential of synthetic oligonucleotides has been developed, which kinds of natural bacterial DNA sequences are responsible for immunostimulation are not known. This work provides evidence that the natural DNA sequences named repetitive extragenic palindromic (REPs) sequences present in Gram-negative bacteria are able to produce innate immune system stimulation via TLR9. A strong induction of IFN-alpha production by REPs from Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa, and Neisseria meningitidis was detected in splenocytes from 129 mice. In addition, the involvement of TLR9 in immune stimulation by REPs was confirmed using B6.129P2-Tlr9(tm1Aki) knockout mice. Considering the involvement of TLRs in Gram-negative septic shock, it is conceivable that REPs play a role in its pathogenesis. This study highlights REPs as a potential novel target in septic shock treatment.

  8. flexTMS--a novel repetitive transcranial magnetic stimulation device with freely programmable stimulus currents.

    PubMed

    Gattinger, Norbert; Moessnang, Georg; Gleich, Bernhard

    2012-07-01

    Transcranial magnetic stimulation (TMS) is able to noninvasively excite neuronal populations due to brief magnetic field pulses. The efficiency and the characteristics of stimulation pulse shapes influence the physiological effect of TMS. However, commercial devices allow only a minimum of control of different pulse shapes. Basically, just sinusoidal and monophasic pulse shapes with fixed pulse widths are available. Only few research groups work on TMS devices with controllable pulse parameters such as pulse shape or pulse width. We describe a novel TMS device with a full-bridge circuit topology incorporating four insulated-gate bipolar transistor (IGBT) modules and one energy storage capacitor to generate arbitrary waveforms. This flexible TMS (flexTMS ) device can generate magnetic pulses which can be adjusted with respect to pulse width, polarity, and intensity. Furthermore, the equipment allows us to set paired pulses with a variable interstimulus interval (ISI) from 0 to 20 ms with a step size of 10  μs. All user-defined pulses can be applied continually with repetition rates up to 30 pulses per second (pps) or, respectively, up to 100 pps in theta burst mode. Offering this variety of flexibility, flexTMS will allow the enhancement of existing TMS paradigms and novel research applications.

  9. Efficacy and practical issues of repetitive transcranial magnetic stimulation on chronic medically unexplained symptoms of pain.

    PubMed

    Li, Cheng-Ta; Su, Tung-Ping; Hsieh, Jen-Chuen; Ho, Shung-Tai

    2013-06-01

    Chronic pain is a common issue worldwide and remains a big challenge to physicians, particularly when the underlying causes do not meet any specific disease for settlement. Such medically unexplained somatic symptoms of pain that lack an integrated diagnosis in medicine have a high psychiatric comorbidity such as depression, and will require a multidisciplinary treatment strategy for a better outcome. Thus, most patients deserted management in spite of being inadequately treated and even presented with high resistance to analgesic drugs. Noninvasive brain stimulation, including repetitive transcranial magnetic stimulation (rTMS), has been used to treat refractory neuropathic pain and the analgesic efficacy is promising. So far, some case series and randomized rTMS studies have reported on patients with certain medically unexplained symptoms (MUSs) of pain (e.g., psychogenic pain or somatic symptoms in major depression and fibromyalgia). However, there is still no review article that is specific to the efficacy of rTMS on chronic unexplained symptoms of pain. Therefore, in the present review, we ventured to clarify the terminology and summarized the analgesic effects of rTMS on chronic MUSs of pain.

  10. Left but not right temporal involvement in opaque idiom comprehension: a repetitive transcranial magnetic stimulation study.

    PubMed

    Oliveri, Massimiliano; Romero, Leonor; Papagno, Costanza

    2004-06-01

    It has been suggested that figurative language, which includes idioms, is controlled by the right hemisphere. We tested the right hemisphere hypothesis by using repetitive transcranial magnetic stimulation (rTMS) to transiently disrupt the function of the frontal and temporal areas of the right versus left hemisphere in a group of normal participants involved in a task of opaque idiom versus literal sentence comprehension. Forty opaque, nonambiguous idioms were selected. Fifteen young healthy participants underwent rTMS in two sessions. The experiment was run in five blocks, corresponding to the four stimulated scalp positions ( left frontal and temporal and right frontal and temporal) and a baseline. Each block consisted of 16 trials-8 trials with idioms and 8 trials with literal sentences. In each trial, the subject was presented with a written sentence, which appeared on the screen for 2000 msec, followed by a pair of pictures for 2500 msec, one of which corresponded to the sentence. The alternative corresponded to the literal meaning for idioms and to a sentence differing in a detail in the case of literal sentences. The subject had to press a button corresponding to the picture matching the string. Reaction times increased following left temporal rTMS, whereas they were unaffected by right hemisphere rTMS, with no difference between idiomatic and literal sentences. Left temporal rTMS also reduced accuracy without differences between the two types of sentences. These data suggest that opaque idiom and literal sentence comprehension depends on the left temporal cortex.

  11. Reduction of Spasticity With Repetitive Transcranial Magnetic Stimulation in Patients With Spinal Cord Injury

    PubMed Central

    Kumru, Hatice; Murillo, Narda; Samso, Joan Vidal; Valls-Sole, Josep; Edwards, Dylan; Pelayo, Raul; Valero-Cabre, Antoni; Tormos, Josep Maria; Pascual-Leone, Alvaro

    2012-01-01

    Objective Spasticity with increased tone and spasms is frequent in patients after spinal cord injury (SCI). Damage to descending corticospinal pathways that normally exert spinal segmental control is thought to play an important causal role in spasticity. The authors examined whether the modulation of excitability of the primary motor cortex with high-frequency repetitive transcranial magnetic stimulation (rTMS) could modify lower limb spasticity in patients with incomplete SCI. Methods Patients were assessed by the Modified Ashworth Scale, Visual Analogue Scale, and the Spinal Cord Injury Spasticity Evaluation Tool (SCI-SET) and neurophysiologically with measures of corticospinal and segmental excitability by the Hmax/Mmax, T reflex, and withdrawal reflex. Fifteen patients received 5 days of daily sessions of active (n = 14) or sham (n = 7) rTMS to the leg motor area (20 trains of 40 pulses at 20 Hz and an intensity of 90% of resting motor threshold for the biceps brachii muscle). Result A significant clinical improvement in lower limb spasticity was observed in patients following active rTMS but not after sham stimulation. This improvement lasted for at least 1 week following the intervention. Neurophysiological studies did not change. Conclusions High-frequency rTMS over the leg motor area can improve aspects of spasticity in patients with incomplete SCI. PMID:20053952

  12. Reduction of spasticity with repetitive transcranial magnetic stimulation in patients with spinal cord injury.

    PubMed

    Kumru, Hatice; Murillo, Narda; Samso, Joan Vidal; Valls-Sole, Josep; Edwards, Dylan; Pelayo, Raul; Valero-Cabre, Antoni; Tormos, Josep Maria; Pascual-Leone, Alvaro

    2010-06-01

    Spasticity with increased tone and spasms is frequent in patients after spinal cord injury (SCI). Damage to descending corticospinal pathways that normally exert spinal segmental control is thought to play an important causal role in spasticity. The authors examined whether the modulation of excitability of the primary motor cortex with high-frequency repetitive transcranial magnetic stimulation (rTMS) could modify lower limb spasticity in patients with incomplete SCI. Patients were assessed by the Modified Ashworth Scale, Visual Analogue Scale, and the Spinal Cord Injury Spasticity Evaluation Tool (SCI-SET) and neurophysiologically with measures of corticospinal and segmental excitability by the H(max)/M(max), T reflex, and withdrawal reflex. Fifteen patients received 5 days of daily sessions of active (n = 14) or sham (n = 7) rTMS to the leg motor area (20 trains of 40 pulses at 20 Hz and an intensity of 90% of resting motor threshold for the biceps brachii muscle). A significant clinical improvement in lower limb spasticity was observed in patients following active rTMS but not after sham stimulation.This improvement lasted for at least 1 week following the intervention. Neurophysiological studies did not change. High-frequency rTMS over the leg motor area can improve aspects of spasticity in patients with incomplete SCI.

  13. Surface-Enhanced Femtosecond Stimulated Raman Spectroscopy at 1 MHz Repetition Rates.

    PubMed

    Buchanan, Lauren E; Gruenke, Natalie L; McAnally, Michael O; Negru, Bogdan; Mayhew, Hannah E; Apkarian, Vartkess A; Schatz, George C; Van Duyne, Richard P

    2016-11-17

    Surface-enhanced femtosecond stimulated Raman spectroscopy (SE-FSRS) is an ultrafast Raman technique that combines the sensitivity of surface-enhanced Raman scattering with the temporal resolution of femtosecond stimulated Raman spectroscopy (FSRS). Here, we present the first successful implementation of SE-FSRS using a 1 MHz amplified femtosecond laser system. We compare SE-FSRS and FSRS spectra measured at 1 MHz and 100 kHz using both equal pump average powers and equal pump energies to demonstrate that higher repetition rates allow spectra with higher signal-to-noise ratios to be obtained at lower pulse energies, a significant advance in the implementation of SE-FSRS. The ability to use lower pulse energies significantly mitigates sample damage that results from plasmonic enhancement of high-energy ultrafast pulses. As a result of the improvements to SE-FSRS developed in this Letter, we believe that SE-FSRS is now poised to become a powerful tool for studying the dynamics of plasmonic materials and adsorbates thereon.

  14. Effects of paired-pulse and repetitive stimulation on neurons in the rat medial geniculate body.

    PubMed

    Bartlett, E L; Smith, P H

    2002-01-01

    Many behaviorally relevant sounds, including language, are composed of brief, rapid, repetitive acoustic features. Recent studies suggest that abnormalities in producing and understanding spoken language are correlated with abnormal neural responsiveness to such auditory stimuli at higher auditory levels [Tallal et al., Science 271 (1996) 81-84; Wright et al., Nature 387 (1997) 176-178; Nagarajan et al., Proc. Natl. Acad. Sci. USA 96 (1999) 6483-6488] and with abnormal anatomical features in the auditory thalamus [Galaburda et al., Proc. Natl. Acad. Sci. USA 91 (1994) 8010-8013]. To begin to understand potential mechanisms for normal and abnormal transfer of sensory information to the cortex, we recorded the intracellular responses of medial geniculate body thalamocortical neurons in a rat brain slice preparation. Inferior colliculus or corticothalamic axons were excited by pairs or trains of electrical stimuli. Neurons receiving only excitatory collicular input had tufted dendritic morphology and displayed strong paired-pulse depression of their large, short-latency excitatory postsynaptic potentials. In contrast, geniculate neurons receiving excitatory and inhibitory collicular inputs could have stellate or tufted morphology and displayed much weaker depression or even paired-pulse facilitation of their smaller, longer-latency excitatory postsynaptic potentials. Depression was not blocked by ionotropic glutamate, GABA(A) or GABA(B) receptor antagonists. Facilitation was unaffected by GABA(A) receptor antagonists but was diminished by N-methyl-D-aspartate (NMDA) receptor blockade. Similar stimulation of the corticothalamic input always elicited paired-pulse facilitation. The NMDA-independent facilitation of the second cortical excitatory postsynaptic potential lasted longer and was more pronounced than that seen for the excitatory collicular inputs. Paired-pulse stimulation of isolated collicular inhibitory postsynaptic potentials generated little change in the

  15. Repetitive transcranial magnetic stimulation induces oscillatory power changes in chronic tinnitus

    PubMed Central

    Schecklmann, Martin; Lehner, Astrid; Gollmitzer, Judith; Schmidt, Eldrid; Schlee, Winfried; Langguth, Berthold

    2015-01-01

    Chronic tinnitus is associated with neuroplastic changes in auditory and non-auditory cortical areas. About 10 years ago, repetitive transcranial magnetic stimulation (rTMS) of auditory and prefrontal cortex was introduced as potential treatment for tinnitus. The resulting changes in tinnitus loudness are interpreted in the context of rTMS induced activity changes (neuroplasticity). Here, we investigate the effect of single rTMS sessions on oscillatory power to probe the capacity of rTMS to interfere with tinnitus-specific cortical plasticity. We measured 20 patients with bilateral chronic tinnitus and 20 healthy controls comparable for age, sex, handedness, and hearing level with a 63-channel electroencephalography (EEG) system. Educational level, intelligence, depressivity and hyperacusis were controlled for by analysis of covariance. Different rTMS protocols were tested: Left and right temporal and left and right prefrontal cortices were each stimulated with 200 pulses at 1 Hz and with an intensity of 60% stimulator output. Stimulation of central parietal cortex with 6-fold reduced intensity (inverted passive-cooled coil) served as sham condition. Before and after each rTMS protocol 5 min of resting state EEG were recorded. The order of rTMS protocols was randomized over two sessions with 1 week interval in between. Analyses on electrode level showed that people with and without tinnitus differed in their response to left temporal and right frontal stimulation. In tinnitus patients left temporal rTMS decreased frontal theta and delta and increased beta2 power, whereas right frontal rTMS decreased right temporal beta3 and gamma power. No changes or increases were observed in the control group. Only non-systematic changes in tinnitus loudness were induced by single sessions of rTMS. This is the first study to show tinnitus-related alterations of neuroplasticity that were specific to stimulation site and oscillatory frequency. The observed effects can be

  16. Action potential propagation through embryonic dorsal root ganglion cells in culture. II. Decrease of conduction reliability during repetitive stimulation.

    PubMed

    Lüscher, C; Streit, J; Lipp, P; Lüscher, H R

    1994-08-01

    1. The reliability of the propagation of action potentials (AP) through dorsal root ganglion (DRG) cells in embryonic slice cultures was investigated during repetitive stimulation at 1-20 Hz. Membrane potentials of DRG cells were recorded intracellularly while the axons were stimulated by an extracellular electrode. 2. In analogy to the double-pulse experiments reported previously, either one or two types of propagation failures were recorded during repetitive stimulation, depending on the cell morphology. In contrast to the double-pulse experiments, the failures appeared at longer interpulse intervals and usually only after several tens of stimuli with reliable propagation. 3. In the period with reliable propagation before the failures, a decrease in the conduction velocity and in the amplitude of the afterhyperpolarization (AHP), an increase in the total membrane conductance, and the disappearance of the action potential "shoulder" were observed. 4. The reliability of conduction during repetitive stimulation was improved by lowering the extracellular calcium concentration or by replacing the extracellular calcium by strontium. The reliability of conduction decreased by the application of cadmium, a calcium channel blocker, 4-amino pyridine, a fast potassium channel blocker, or apamin or muscarine, the blockers of calcium-dependent potassium channels. The reliability of conduction was not effected by blocking the sodium potassium pump with ouabain or by replacing extracellular sodium with lithium. 5. In the period with reliable propagation cadmium, apamin, and muscarine reduced the amplitude of the AHP. The shoulder of the action potential was more pronounced and not sensitive to repetitive stimulation when extracellular calcium was replaced by strontium. It disappeared when cadmium was applied. 6. In DRG somata changes of the intracellular Ca2+ concentration were monitored by measuring the fluorescence of the Ca2+ indicator Fluo-3 with a laser-scanning confocal

  17. Inactivation of mechano-sensitive dilatation upon repetitive mechanical stimulation of the musculo-vascular network in the rabbit.

    PubMed

    Turturici, M; Roatta, S

    2013-06-01

    Mechano-sensitivity of the vascular network is known to be implicated in the rapid dilatation at the onset of exercise, however, it is not known how this mechanism responds to repetitive mechanical stimulation. This study tests the hypothesis that the mechanically-induced hyperaemia undergoes some attenuation upon repetitive stimulation. Muscle blood flow was recorded from 9 masseteric arteries (5 right, 4 left) in 6 anesthetized rabbits. Two mechanical stimuli, masseter muscle compression (MC) and occlusion of the masseteric artery (AO), were provided in different combinations: A) repeated stimulation (0.5 Hz, for 40 s); B) single stimuli delivered at decreasing inter-stimulus interval (ISI) from 4 min to 2 s, C) single AO delivered before and immediately after a series of 20 MCs at 0.5 Hz, and vice-versa. Repetitive AO stimulation at 0.5 Hz produced a transient hyperaemia (378 ±189%) peaking at 4.5 ±1.4 s and then decaying before the end of stimulation. The hyperaemic response to individual AOs progressively decreased by 74 ±39% with decreasing ISI from 4 min to 2 s (p<0.01). Non significant differences were observed between AO and MC stimulation. Decreased response to AO was also provoked by previous repetitive MC stimulation, and vice-versa. The results provide evidence that the mechano-sensitivity of the vascular network is attenuated by previous mechanical stimulation. It is suggested that the mechano-sensitive dilatory mechanisms undergoes some inactivation whose recovery time is in the order of a few minutes.

  18. Safety of repetitive transcranial magnetic stimulation in patients with epilepsy: A systematic review.

    PubMed

    Pereira, Luisa Santos; Müller, Vanessa Teixeira; da Mota Gomes, Marleide; Rotenberg, Alexander; Fregni, Felipe

    2016-04-01

    Approximately one-third of patients with epilepsy remain with pharmacologically intractable seizures. An emerging therapeutic modality for seizure suppression is repetitive transcranial magnetic stimulation (rTMS). Despite being considered a safe technique, rTMS carries the risk of inducing seizures, among other milder adverse events, and thus, its safety in the population with epilepsy should be continuously assessed. We performed an updated systematic review on the safety and tolerability of rTMS in patients with epilepsy, similar to a previous report published in 2007 (Bae EH, Schrader LM, Machii K, Alonso-Alonso M, Riviello JJ, Pascual-Leone A, Rotenberg A. Safety and tolerability of repetitive transcranial magnetic stimulation in patients with epilepsy: a review of the literature. Epilepsy Behav. 2007; 10 (4): 521-8), and estimated the risk of seizures and other adverse events during or shortly after rTMS application. We searched the literature for reports of rTMS being applied on patients with epilepsy, with no time or language restrictions, and obtained studies published from January 1990 to August 2015. A total of 46 publications were identified, of which 16 were new studies published after the previous safety review of 2007. We noted the total number of subjects with epilepsy undergoing rTMS, medication usage, incidence of adverse events, and rTMS protocol parameters: frequency, intensity, total number of stimuli, train duration, intertrain intervals, coil type, and stimulation site. Our main data analysis included separate calculations for crude per subject risk of seizure and other adverse events, as well as risk per 1000 stimuli. We also performed an exploratory, secondary analysis on the risk of seizure and other adverse events according to the type of coil used (figure-of-8 or circular), stimulation frequency (≤ 1 Hz or > 1 Hz), pulse intensity in terms of motor threshold (<100% or ≥ 100%), and number of stimuli per session (< 500 or ≥ 500

  19. High-speed IR imaging of repetitive events using a standard RS-170 imager

    NASA Astrophysics Data System (ADS)

    Shepard, Steven M.; Sass, David T.; Imirowicz, Thomas P.

    1992-01-01

    We have developed a system which allows repetitive events at frequencies up to 4 kHz to be imaged without aliasing. An off-the-shelf optomechanical imager (Inframetrics IR 600) is used in conjunction with a microcomputer and a specially developed hardware interface. The effective integration time of the system is equivalent to the horizontal line scan time (125 microsecond(s) ). Images are constructed by acquiring horizontal lines which are in phase with a reference signal emanating from the target. Multiple occurrences of a given line are displayed as a linear average so that the in-phase component appears amplified in the final image. Images of flame front propagation in an operating engine combustion chamber, and transient spatial heat distribution in a transistor operating at 2.5 kHz have been acquired.

  20. Functional repetitive transcranial magnetic stimulation increases motor cortex excitability in survivors of stroke.

    PubMed

    Massie, Crystal L; Tracy, Brian L; Malcolm, Matthew P

    2013-02-01

    To determine if repetitive transcranial magnetic stimulation (rTMS) applied to the motor cortex with simultaneous voluntary muscle activation, termed functional-rTMS, will promote greater neuronal excitability changes and neural plasticity than passive-rTMS in survivors of stroke. Eighteen stroke survivors were randomized into functional-rTMS (EMG-triggered rTMS) or passive-rTMS (rTMS only; control) conditions. Measures of short-interval intracortical inhibition (SICI) and intracortical facilitation (ICF), force steadiness (coefficient of variation, CV) at 10% of maximum voluntary contraction, and pinch task muscle activity were assessed before and after rTMS. Functional-rTMS required subjects to exceed a muscle activation threshold to trigger each rTMS train; the passive-rTMS group received rTMS while relaxed. Significant interactions (time × condition) were observed in abductor pollicis brevis (APB) SICI, APB ICF, CV of force, and APB muscle activity. Functional-rTMS decreased APB SICI (p < 0.05) and increased ICF (p < 0.05) after stimulation, whereas passive-rTMS decreased APB muscle activity (p < 0.01) and decreased CV of force (p < 0.05). No changes were observed in FDI measures (EMG, ICF, SICI). Functional-rTMS increased motor cortex excitability, i.e., less SICI and more ICF for the APB muscle. Passive stimulation significantly reduced APB muscle activity and improved steadiness. Functional-rTMS promoted greater excitability changes and selectively modulated agonist muscle activity. Copyright © 2012 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  1. A Randomised Controlled Trial of Neuronavigated Repetitive Transcranial Magnetic Stimulation (rTMS) in Anorexia Nervosa.

    PubMed

    McClelland, Jessica; Kekic, Maria; Bozhilova, Natali; Nestler, Steffen; Dew, Tracy; Van den Eynde, Frederique; David, Anthony S; Rubia, Katya; Campbell, Iain C; Schmidt, Ulrike

    2016-01-01

    Anorexia nervosa (AN) is associated with morbid fear of fatness, extreme food restriction and altered self-regulation. Neuroimaging data implicate fronto-striatal circuitry, including the dorsolateral prefrontal cortex (DLPFC). In this double-blind parallel group study, we investigated the effects of one session of sham-controlled high-frequency repetitive transcranial magnetic stimulation (rTMS) to the left DLPFC (l-DLPFC) in 60 individuals with AN. A food exposure task was administered before and after the procedure to elicit AN-related symptoms. The primary outcome measure was 'core AN symptoms', a variable which combined several subjective AN-related experiences. The effects of rTMS on other measures of psychopathology (e.g. mood), temporal discounting (TD; intertemporal choice behaviour) and on salivary cortisol concentrations were also investigated. Safety, tolerability and acceptability were assessed. Fourty-nine participants completed the study. Whilst there were no interaction effects of rTMS on core AN symptoms, there was a trend for group differences (p = 0.056): after controlling for pre-rTMS scores, individuals who received real rTMS had reduced symptoms post-rTMS and at 24-hour follow-up, relative to those who received sham stimulation. Other psychopathology was not altered differentially following real/sham rTMS. In relation to TD, there was an interaction trend (p = 0.060): real versus sham rTMS resulted in reduced rates of TD (more reflective choice behaviour). Salivary cortisol concentrations were unchanged by stimulation. rTMS was safe, well-tolerated and was considered an acceptable intervention. This study provides modest evidence that rTMS to the l-DLPFC transiently reduces core symptoms of AN and encourages prudent decision making. Importantly, individuals with AN considered rTMS to be a viable treatment option. These findings require replication in multiple-session studies to evaluate therapeutic efficacy. www.Controlled-Trials.com ISRCTN

  2. Brain SPECT guided repetitive transcranial magnetic stimulation (rTMS) in treatment resistant major depressive disorder.

    PubMed

    Jha, Shailesh; Chadda, Rakesh K; Kumar, Nand; Bal, C S

    2016-06-01

    Repetitive transcranial magnetic stimulation (rTMS) has emerged as a potential treatment in treatment resistant major depressive disorder (MDD). However, there is no consensus about the exact site of stimulation for rTMS. Single-photon emission computed tomography (SPECT) offers a potential technique in deciding the site of stimulation. The present study was conducted to assess the difference in outcome of brain SPECT assisted rTMS versus standard protocol of twenty sessions of high frequency rTMS as add on treatment in 20 patients with treatment resistant MDD, given over a period of 4 weeks. Thirteen subjects (group I) received high frequency rTMS over an area of hypoperfusion in the prefrontal cortex, as identified on SPECT, whereas 7 subjects (group II) were administered rTMS in the left dorsoslateral prefrontal cortex (DLPFC) area. Improvement was monitored using standardized instruments. Patients in the group I showed a significantly better response compared to those in the group II. In group I, 46% of the subjects were responders on MADRS, 38% on BDI and 77% on CGI. The parallel figures of responders in Group II were 0% on MADRS, 14% on BDI and 43% on CGI. There were no remitters in the study. No significant untoward side effects were noticed. The study had limitations of a small sample size and non-controlled design, and all the subjects were also receiving the standard antidepressant therapy. Administration of rTMS over brain SPECT specified area of hypoperfusion may have a better clinical outcome compared to the standard protocol.

  3. Focal hand dystonia: individualized intervention with repeated application of repetitive transcranial magnetic stimulation

    PubMed Central

    Kimberley, Teresa Jacobson; Borich, Michael R.; Schmidt, Rebekah; Carey, James R.; Gillick, Bernadette

    2016-01-01

    Objective Examine for individual factors that may predict response to inhibitory repetitive transcranial magnetic stimulation (rTMS) in focal hand dystonia (FHD); present method for determining the optimal stimulation to increase inhibition in a given patient; and examine individual responses to prolonged intervention. Design A single-subject design to determine optimal parameters to increase inhibition for a given subject and to employ the selected parameters 1/wk for 6 weeks, with 1 wk follow up, to determine response. Setting Clinical research laboratory Participants A volunteer sample of 2 subjects with FHD. One participant had TMS responses indicating impaired inhibition, the other had responses within normal limits. Interventions 1200 pulses of 1 Hz rTMS delivered using 4 different stimulation site/intensity combinations: primary motor cortex (M1) at 90% or 110% resting motor threshold (RMT); dorsal premotor cortex (PMd) at 90% or 110% of RMT. The parameters producing the greatest within-session increase in cortical silent period (CSP) duration were then used as intervention. Main outcome measures Response variables included handwriting pressure and velocity, subjective symptom rating, CSP, and short-latency intracortical inhibition and facilitation. Results The individual with baseline TMS responses indicating impaired inhibition responded favorably to the repeated intervention, with reduced handwriting force, increase in CSP and subjective report of “moderate” symptom improvement at 1-wk follow-up. The individual with normal baseline responses failed to respond to the intervention. In both subjects, 90% RMT to PMd produced greatest lengthening of CSP and was used as intervention. Conclusions An individualized understanding of neurophysiologic measures may be indicators of responsiveness to inhibitory rTMS in focal dystonia, with further work needed to determine 3 likely responders vs. non-responders. PMID:25256555

  4. A systematic review for the antidepressant effects of sleep deprivation with repetitive transcranial magnetic stimulation.

    PubMed

    Tang, Qing; Li, Guangming; Wang, Anguo; Liu, Tao; Feng, Shenggang; Guo, Zhiwei; Chen, Huaping; He, Bin; McClure, Morgan A; Ou, Jun; Xing, Guoqiang; Mu, Qiwen

    2015-11-14

    Sleep deprivation (SD) and repetitive transcranial magnetic stimulation (rTMS) have been commonly used to treat depression. Recent studies suggest that co-therapy with rTMS and SD may produce better therapeutic effects than either therapy alone. Therefore, this study was to review the current findings to determine if rTMS can augment the therapeutic effects of SD on depression. Embase, JSTOR, Medline, PubMed, ScienceDirect, and the Cochrane Central Register of Controlled Trials were searched for clinical studies published between January 1985 and March 2015 using the search term "rTMS/repetitive transcranial magnetic stimulation AND sleep deprivation AND depress*". Only randomized and sham-controlled trials (RCTs) involving the combined use of rTMS and SD in depression patients were included in this systematic review. The scores of the Hamilton Rating Scale for Depression were extracted as primary outcome measures. Three RCTs with 72 patients that met the inclusion criteria were included for the systematic review. One of the trials reported skewed data and was described alone. The other two studies, which involved 30 patients in the experimental group (SD + active rTMS) and 22 patients in the control group (SD + sham rTMS), reported normally distributed data. The primary outcome measures showed different results among the three publications: two of which showed great difference between the experimental and the control subjects, and the other one showed non-significant antidepressant effect of rTMS on SD. In addition, two of the included studies reported secondary outcome measures with Clinical Global Impression Rating Scale and a self-reported well-being scale which presented good improvement for the depressive patients in the experiment group when compared with the control. The follow-up assessments in two studies indicated maintained results with the immediate measurements. From this study, an overview of the publications concerning the combined use of rTMS and

  5. Effects of Repetitive Transcranial Magnetic Stimulation in Performing Eye-Hand Integration Tasks: Four Preliminary Studies with Children Showing Low-Functioning Autism

    ERIC Educational Resources Information Center

    Panerai, Simonetta; Tasca, Domenica; Lanuzza, Bartolo; Trubia, Grazia; Ferri, Raffaele; Musso, Sabrina; Alagona, Giovanna; Di Guardo, Giuseppe; Barone, Concetta; Gaglione, Maria P.; Elia, Maurizio

    2014-01-01

    This report, based on four studies with children with low-functioning autism, aimed at evaluating the effects of repetitive transcranial magnetic stimulation delivered on the left and right premotor cortices on eye-hand integration tasks; defining the long-lasting effects of high-frequency repetitive transcranial magnetic stimulation; and…

  6. Effects of Repetitive Transcranial Magnetic Stimulation in Performing Eye-Hand Integration Tasks: Four Preliminary Studies with Children Showing Low-Functioning Autism

    ERIC Educational Resources Information Center

    Panerai, Simonetta; Tasca, Domenica; Lanuzza, Bartolo; Trubia, Grazia; Ferri, Raffaele; Musso, Sabrina; Alagona, Giovanna; Di Guardo, Giuseppe; Barone, Concetta; Gaglione, Maria P.; Elia, Maurizio

    2014-01-01

    This report, based on four studies with children with low-functioning autism, aimed at evaluating the effects of repetitive transcranial magnetic stimulation delivered on the left and right premotor cortices on eye-hand integration tasks; defining the long-lasting effects of high-frequency repetitive transcranial magnetic stimulation; and…

  7. [French guidelines on the use of repetitive transcranial magnetic stimulation (rTMS): safety and therapeutic indications].

    PubMed

    Lefaucheur, J-P; André-Obadia, N; Poulet, E; Devanne, H; Haffen, E; Londero, A; Cretin, B; Leroi, A-M; Radtchenko, A; Saba, G; Thai-Van, H; Litré, C-F; Vercueil, L; Bouhassira, D; Ayache, S-S; Farhat, W-H; Zouari, H-G; Mylius, V; Nicolier, M; Garcia-Larrea, L

    2011-12-01

    During the past decade, a large amount of work on transcranial magnetic stimulation (TMS) has been performed, including the development of new paradigms of stimulation, the integration of imaging data, and the coupling of TMS techniques with electroencephalography or neuroimaging. These accumulating data being difficult to synthesize, several French scientific societies commissioned a group of experts to conduct a comprehensive review of the literature on TMS. This text contains all the consensual findings of the expert group on the mechanisms of action, safety rules and indications of TMS, including repetitive TMS (rTMS). TMS sessions have been conducted in thousands of healthy subjects or patients with various neurological or psychiatric diseases, allowing a better assessment of risks associated with this technique. The number of reported side effects is extremely low, the most serious complication being the occurrence of seizures. In most reported seizures, the stimulation parameters did not follow the previously published recommendations (Wassermann, 1998) [430] and rTMS was associated to medication that could lower the seizure threshold. Recommendations on the safe use of TMS / rTMS were recently updated (Rossi et al., 2009) [348], establishing new limits for stimulation parameters and fixing the contraindications. The recommendations we propose regarding safety are largely based on this previous report with some modifications. By contrast, the issue of therapeutic indications of rTMS has never been addressed before, the present work being the first attempt of a synthesis and expert consensus on this topic. The use of TMS/rTMS is discussed in the context of chronic pain, movement disorders, stroke, epilepsy, tinnitus and psychiatric disorders. There is already a sufficient level of evidence of published data to retain a therapeutic indication of rTMS in clinical practice (grade A) in chronic neuropathic pain, major depressive episodes, and auditory

  8. 5 Hz repetitive transcranial magnetic stimulation over the ipsilesional sensory cortex enhances motor learning after stroke

    PubMed Central

    Brodie, Sonia M.; Meehan, Sean; Borich, Michael R.; Boyd, Lara A.

    2014-01-01

    Sensory feedback is critical for motor learning, and thus to neurorehabilitation after stroke. Whether enhancing sensory feedback by applying excitatory repetitive transcranial magnetic stimulation (rTMS) over the ipsilesional primary sensory cortex (IL-S1) might enhance motor learning in chronic stroke has yet to be investigated. The present study investigated the effects of 5 Hz rTMS over IL-S1 paired with skilled motor practice on motor learning, hemiparetic cutaneous somatosensation, and motor function. Individuals with unilateral chronic stroke were pseudo-randomly divided into either Active or Sham 5 Hz rTMS groups (n = 11/group). Following stimulation, both groups practiced a Serial Tracking Task (STT) with the hemiparetic arm; this was repeated for 5 days. Performance on the STT was quantified by response time, peak velocity, and cumulative distance tracked at baseline, during the 5 days of practice, and at a no-rTMS retention test. Cutaneous somatosensation was measured using two-point discrimination. Standardized sensorimotor tests were performed to assess whether the effects might generalize to impact hemiparetic arm function. The active 5 Hz rTMS + training group demonstrated significantly greater improvements in STT performance {response time [F(1, 286.04) = 13.016, p < 0.0005], peak velocity [F(1, 285.95) = 4.111, p = 0.044], and cumulative distance [F(1, 285.92) = 4.076, p = 0.044]} and cutaneous somatosensation [F(1, 21.15) = 8.793, p = 0.007] across all sessions compared to the sham rTMS + training group. Measures of upper extremity motor function were not significantly different for either group. Our preliminary results suggest that, when paired with motor practice, 5 Hz rTMS over IL-S1 enhances motor learning related change in individuals with chronic stroke, potentially as a consequence of improved cutaneous somatosensation, however no improvement in general upper extremity function was observed. PMID:24711790

  9. Repetitive magnetic stimulation improves retinal function in a rat model of retinal dystrophy

    NASA Astrophysics Data System (ADS)

    Rotenstreich, Ygal; Tzameret, Adi; Levi, Nir; Kalish, Sapir; Sher, Ifat; Zangen, Avraham; Belkin, Michael

    2014-02-01

    Vision incapacitation and blindness associated with retinal dystrophies affect millions of people worldwide. Retinal degeneration is characterized by photoreceptor cell death and concomitant remodeling of remaining retinal cells. Repetitive Magnetic Stimulation (RMS) is a non-invasive technique that creates alternating magnetic fields by brief electric currents transmitted through an insulated coil. These magnetic field generate action potentials in neurons, and modulate the expression of neurotransmitter receptors, growth factors and transcription factors which mediate plasticity. This technology has been proven effective and safe in various psychiatric disorders. Here we determined the effect of RMS on retinal function in Royal College of Surgeons (RCS) rats, a model for retinal dystrophy. Four week-old RCS and control Spargue Dawley (SD) rats received sham or RMS treatment over the right eye (12 sessions on 4 weeks). RMS treatment at intensity of at 40% of the maximal output of a Rapid2 stimulator significantly increased the electroretinogram (ERG) b-wave responses by up to 6- or 10-fold in the left and right eye respectively, 3-5 weeks following end of treatment. RMS treatment at intensity of 25% of the maximal output did not significant effect b-wave responses following end of treatment with no adverse effect on ERG response or retinal structure of SD rats. Our findings suggest that RMS treatment induces delayed improvement of retinal functions and may induce plasticity in the retinal tissue. Furthermore, this non-invasive treatment may possibly be used in the future as a primary or adjuvant treatment for retinal dystrophy.

  10. Poststroke dysphagia rehabilitation by repetitive transcranial magnetic stimulation: a noncontrolled pilot study.

    PubMed

    Verin, E; Leroi, A M

    2009-06-01

    Poststroke dysphagia is frequent and significantly increases patient mortality. In two thirds of cases there is a spontaneous improvement in a few weeks, but in the other third, oropharyngeal dysphagia persists. Repetitive transcranial magnetic stimulation (rTMS) is known to excite or inhibit cortical neurons, depending on stimulation frequency. The aim of this noncontrolled pilot study was to assess the feasibility and the effects of 1-Hz rTMS, known to have an inhibitory effect, on poststroke dysphagia. Seven patients (3 females, age = 65 +/- 10 years), with poststroke dysphagia due to hemispheric or subhemispheric stroke more than 6 months earlier (56 +/- 50 months) diagnosed by videofluoroscopy, participated in the study. rTMS at 1 Hz was applied for 20 min per day every day for 5 days to the healthy hemisphere to decrease transcallosal inhibition. The evaluation was performed using the dysphagia handicap index and videofluoroscopy. The dysphagia handicap index demonstrated that the patients had mild oropharyngeal dysphagia. Initially, the score was 43 +/- 9 of a possible 120 which decreased to 30 +/- 7 (p < 0.05) after rTMS. After rTMS, there was an improvement of swallowing coordination, with a decrease in swallow reaction time for liquids (p = 0.0506) and paste (p < 0.01), although oral transit time, pharyngeal transit time, and laryngeal closure duration were not modified. Aspiration score significantly decreased for liquids (p < 0.05) and residue score decreased for paste (p < 0.05). This pilot study demonstrated that rTMS is feasible in poststroke dysphagia and improves swallowing coordination. Our results now need to be confirmed by a randomized controlled study with a larger patient population.

  11. Mechanisms of human motor cortex facilitation induced by subthreshold 5-Hz repetitive transcranial magnetic stimulation.

    PubMed

    Sommer, Martin; Rummel, Milena; Norden, Christoph; Rothkegel, Holger; Lang, Nicolas; Paulus, Walter

    2013-06-01

    Our knowledge about the mechanisms of human motor cortex facilitation induced by repetitive transcranial magnetic stimulation (rTMS) is still incomplete. Here we used pharmacological conditioning with carbamazepine, dextrometorphan, lorazepam, and placebo to elucidate the type of plasticity underlying this facilitation, and to probe if mechanisms reminiscent of long-term potentiation are involved. Over the primary motor cortex of 10 healthy subjects, we applied biphasic rTMS pulses of effective posterior current direction in the brain. We used six blocks of 200 pulses at 5-Hz frequency and 90% active motor threshold intensity and controlled for corticospinal excitability changes using motor-evoked potential (MEP) amplitudes and latencies elicited by suprathreshold pulses before, in between, and after rTMS. Target muscle was the dominant abductor digiti minimi muscle; we coregistered the dominant extensor carpi radialis muscle. We found a lasting facilitation induced by this type of rTMS. The GABAergic medication lorazepam and to a lesser extent the ion channel blocker carbamazepine reduced the MEP facilitation after biphasic effective posteriorly oriented rTMS, whereas the N-methyl-d-aspartate receptor-antagonist dextrometorphan had no effect. Our main conclusion is that the mechanism of the facilitation induced by biphasic effective posterior rTMS is more likely posttetanic potentiation than long-term potentiation. Additional findings were prolonged MEP latency under carbamazepine, consistent with sodium channel blockade, and larger MEP amplitudes from extensor carpi radialis under lorazepam, suggesting GABAergic involvement in the center-surround balance of excitability.

  12. Disruption of Locomotor Adaptation with Repetitive Transcranial Magnetic Stimulation Over the Motor Cortex.

    PubMed

    Choi, Julia T; Bouyer, Laurent J; Nielsen, Jens Bo

    2015-07-01

    Locomotor patterns are adapted on a trial-and-error basis to account for predictable dynamics. Once a walking pattern is adapted, the new calibration is stored and must be actively de-adapted. Here, we tested the hypothesis that storage of newly acquired ankle adaptation in walking is dependent on corticospinal mechanisms. Subjects were exposed to an elastic force that resisted ankle dorsiflexion during treadmill walking. Ankle movement was adapted in <30 strides, leading to after-effects on removal of the force. We used a crossover design to study the effects of repetitive transcranial magnetic stimulation (TMS) over the primary motor cortex (M1), compared with normal adaptation without TMS. In addition, we tested the effects of TMS over the primary sensory cortex (S1) and premotor cortex (PMC) during adaptation. We found that M1 TMS, but not S1 TMS and PMC TMS, reduced the size of ankle dorsiflexion after-effects. The results suggest that suprathreshold M1 TMS disrupted the initial processes underlying locomotor adaptation. These results are consistent with the hypothesis that corticospinal mechanisms underlie storage of ankle adaptation in walking.

  13. Short-term effects of repetitive transcranial magnetic stimulation on sleep bruxism - a pilot study.

    PubMed

    Zhou, Wei-Na; Fu, Hai-Yang; Du, Yi-Fei; Sun, Jian-Hua; Zhang, Jing-Lu; Wang, Chen; Svensson, Peter; Wang, Ke-Lun

    2016-03-30

    The purpose of this study was to investigate the effects of repetitive transcranial magnetic stimulation (rTMS) on patients with sleep bruxism (SB). Twelve patients with SB were included in an open, single-intervention pilot study. rTMS at 1 Hz and an intensity of 80% of the active motor threshold was applied to the 'hot spot' of the masseter muscle representation at the primary motor cortex bilaterally for 20 min per side each day for 5 consecutive days. The jaw-closing muscle electromyographic (EMG) activity during sleep was recorded with a portable EMG recorder at baseline, during rTMS treatment and at follow-up for 5 days. In addition, patients scored their jaw-closing muscle soreness on a 0-10 numerical rating scale (NRS). Data were analysed with analysis of variance. The intensity of the EMG activity was suppressed during and after rTMS compared to the baseline (P = 0.04; P = 0.02, respectively). The NRS score of soreness decreased significantly during and after rTMS compared with baseline (P < 0.01). These findings indicated a significant inhibition of jaw-closing muscle activity during sleep along with a decrease of muscle soreness. This pilot study raises the possibility of therapeutic benefits from rTMS in patients with bruxism and calls for further and more controlled studies.

  14. Modulation of visual evoked potentials by high-frequency repetitive transcranial magnetic stimulation in migraineurs.

    PubMed

    Omland, Petter M; Uglem, Martin; Engstrøm, Morten; Linde, Mattias; Hagen, Knut; Sand, Trond

    2014-10-01

    High-frequency repetitive transcranial magnetic stimulation (rTMS) modulates cortical excitability. We investigated its effect on visual evoked potentials (VEPs) in migraine. Thirty-two headache-free controls (CO), 25 interictal (MINT) and 7 preictal migraineurs (MPRE) remained after exclusions. VEPs to 8' and 65' checks were averaged in six blocks of 100 single responses. VEPs were recorded before, directly after and 25min after 10Hz rTMS. The study was blinded for diagnosis during recording and for diagnosis and block number during analysis. First block amplitudes and habituation (linear amplitude change over blocks) were analysed with repeated measures ANOVA. With 65' checks, N70-P100 habituation was reduced in MINT compared to CO after rTMS (p=0.013). With 8' checks, habituation was reduced in MPRE compared to MINT and CO after rTMS (p<0.016). No effects of rTMS on first block amplitudes were found. RTMS reduced habituation only in migraineurs, indicating increased responsivity to rTMS. The magnocellular visual subsystem may be affected interictally, while the parvocellular system may only be affected preictally. Migraineurs may have increased responsiveness to rTMS because of a cortical dysfunction that changes before a migraine attack. Copyright © 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  15. Combining near-infrared spectroscopy with electroencephalography and repetitive transcranial magnetic stimulation

    NASA Astrophysics Data System (ADS)

    Näsi, Tiina; Kotilahti, Kalle; Mäki, Hanna; Nissilä, Ilkka; Meriläinen, Pekka

    2009-07-01

    The objective of the study was to assess the usability of a near-infrared spectroscopy (NIRS) device in multimodal measurements. We combined NIRS with electroencephalography (EEG) to record hemodynamic responses and evoked potentials simultaneously, and with transcranial magnetic stimulation (TMS) to investigate hemodynamic responses to repetitive TMS (rTMS). Hemodynamic responses and visual evoked potentials (VEPs) to 3, 6, and 12 s stimuli consisting of pattern-reversing checkerboards were successfully recorded in the NIRS/EEG measurement, and ipsi- and contralateral hemodynamic responses to 0.5, 1, and 2 Hz rTMS in the NIRS/TMS measurement. In the NIRS/EEG measurements, the amplitudes of the hemodynamic responses increased from 3- to 6-s stimulus, but not from 6- to 12-s stimulus, and the VEPs showed peaks N75, P100, and N135. In the NIRS/TMS measurements, the 2-Hz stimulus produced the strongest hemodynamic responses compared to the 0.5- and 1-Hz stimuli. In two subjects oxyhemoglobin concentration decreased and in one increased as a consequence of the 2-Hz rTMS. To locate the origin of the measured NIRS responses, methods have to be developed to investigate TMS-induced scalp muscle contractions. In the future, multimodal measurements may prove useful in monitoring or treating diseases such as stroke or Alzheimer's disease.

  16. Effects of Repetitive Transcranial Magnetic Stimulation Over Trunk Motor Spot on Balance Function in Stroke Patients

    PubMed Central

    2016-01-01

    Objective To assess the efficacy of high-frequency repetitive transcranial magnetic stimulation (rTMS) on balance function in patients with chronic stroke. Methods Thirty participants with chronic stroke were enrolled in this study. High frequency (10 Hz) rTMS was delivered with butterfly-coil on trunk motor spot. Each patient received both real and sham rTMS in a random sequence. The rTMS cycles (real or sham) were composed of 10 sessions each, administered over two weeks, and separated by a 4-week washout period. Balance function was measured by Berg Balance Scale and computerized dynamic posturography to determine the effect of rTMS before and one day after the end of each treatment period, as well as at a 1-month follow-up. Results The balance function was significantly improved after high frequency rTMS as compared with that after sham rTMS (p<0.05). There was no serious adverse effect in patients during the treatment period. Conclusion In the chronic stroke patients, high frequency rTMS to the trunk motor area seems to be a helpful way to improve balance function without any specific adverse effects. Further studies are needed to identify the underlying mechanism and generate a detailed protocol. PMID:27847712

  17. Online repetitive transcranial magnetic stimulation (TMS) to the parietal operculum disrupts haptic memory for grasping.

    PubMed

    Cattaneo, Luigi; Maule, Francesca; Tabarelli, Davide; Brochier, Thomas; Barchiesi, Guido

    2015-11-01

    The parietal operculum (OP) contains haptic memory on the geometry of objects that is readily transferrable to the motor cortex but a causal role of OP in memory-guided grasping is only speculative. We explored this issue by using online high-frequency repetitive transcranial magnetic stimulation (rTMS). The experimental task was performed by blindfolded participants acting on objects of variable size. Trials consisted in three phases: haptic exploration of an object, delay, and reach-grasp movement onto the explored object. Motor performance was evaluated by the kinematics of finger aperture. Online rTMS was applied to the left OP region separately in each of the three phases of the task. The results showed that rTMS altered grip aperture only when applied in the delay phase to the OP. In a second experiment a haptic discriminative (match-to-sample) task was carried out on objects similar to those used in the first experiment. Online rTMS was applied to the left OP. No psychophysical effects were induced by rTMS on the detection of explicit haptic object size. We conclude that neural activity in the OP region is necessary for proficient memory-guided haptic grasping. The function of OP seems to be critical while maintaining the haptic memory trace and less so while encoding it or retrieving it.

  18. Effects of repetitive transcranial magnetic stimulation on recovery of function after spinal cord injury.

    PubMed

    Tazoe, Toshiki; Perez, Monica A

    2015-04-01

    A major goal of rehabilitation strategies after spinal cord injury (SCI) is to enhance the recovery of function. One possible avenue to achieve this goal is to strengthen the efficacy of the residual neuronal pathways. Noninvasive repetitive transcranial magnetic stimulation (rTMS) has been used in patients with motor disorders as a tool to modulate activity of corticospinal, cortical, and subcortical pathways to promote functional recovery. This article reviews a series of studies published during the last decade that used rTMS in the acute and chronic stages of paraplegia and tetraplegia in humans with complete and incomplete SCI. In the studies, rTMS has been applied over the arm and leg representations of the primary motor cortex to target 3 main consequences of SCI: sensory and motor function impairments, spasticity, and neuropathic pain. Although some studies demonstrated that consecutive sessions of rTMS improve aspects of particular functions, other studies did not show similar effects. We discuss how rTMS parameters and postinjury reorganization in the corticospinal tract, motor cortical, and spinal cord circuits might be critical factors in understanding the advantages and disadvantages of using rTMS in patients with SCI. The available data highlight the limited information on the use of rTMS after SCI and the need to further understand the pathophysiology of neuronal structures affected by rTMS to maximize the potential beneficial effects of this technique in humans with SCI.

  19. Repetitive transcranial magnetic stimulator with controllable pulse parameters (cTMS).

    PubMed

    Peterchev, Angel V; Murphy, David L; Lisanby, Sarah H

    2010-01-01

    We describe a novel transcranial magnetic stimulation (TMS) device that uses a circuit topology incorporating two energy-storage capacitors and two insulated-gate bipolar transistors (IGBTs) to generate near-rectangular electric field E-field) pulses with adjustable number, polarity, duration, and amplitude of the pulse phases. This controllable-pulse-parameter TMS (cTMS) device can induce E-field pulses with phase widths of 5-200 µs and positive/negative phase amplitude ratio of 1-10. Compared to conventional monophasic and biphasic TMS, cTMS reduces energy dissipation by 78-82% and 55-57% and decreases coil heating by 15-33% and 31-41%, respectively. We demonstrate repetitive TMS (rTMS) trains of 3,000 pulses at frequencies up to 50 Hz with E-field pulse amplitude and width variability of less than 1.7% and 1%, respectively. The reduced power consumption and coil heating, and the flexible pulse parameter adjustment offered by cTMS could enhance existing TMS paradigms and could enable novel research and clinical applications with potentially enhanced potency.

  20. Factor Analysis of Low-Frequency Repetitive Transcranial Magnetic Stimulation to the Temporoparietal Junction for Tinnitus

    PubMed Central

    Li, Bei; Wang, Meiye; Li, Ming; Yin, Shankai

    2016-01-01

    Objectives. We investigated factors that contribute to suppression of tinnitus after repetitive transcranial magnetic stimulation (rTMS). Methods. A total of 289 patients with tinnitus underwent active 1 Hz rTMS in the left temporoparietal region. A visual analog scale (VAS) was used to assess tinnitus loudness. All participants were interviewed regarding age, gender, tinnitus duration, laterality and pitch, audiometric parameters, sleep, and so forth. The resting motor thresholds (RMTs) were measured in all patients and 30 age- and gender-matched volunteers. Results. With respect to different factors that contribute to tinnitus suppression, we found improvement in the following domains: shorter duration, normal hearing (OR: 3.25, 95%CI: 2.01–5.27, p = 0.001), and without sleep disturbance (OR: 2.51, 95%CI: 1.56–4.1, p = 0.005) adjusted for age and gender. The patients with tinnitus lasting less than 1 year were more likely to show suppression of tinnitus (OR: 2.77, 95%CI: 1.48–5.19, p = 0.002) compared to those with tinnitus lasting more than 5 years. Tinnitus patients had significantly lower RMTs compared with healthy volunteers. Conclusion. Active low-frequency rTMS results in a significant reduction in the loudness of tinnitus. Significant tinnitus suppression was shown in subjects with shorter tinnitus duration, with normal hearing, and without sleep disturbance. PMID:27847647

  1. A Comprehensive Study of Repetitive Transcranial Magnetic Stimulation in Parkinson's Disease

    PubMed Central

    Kimura, Hideki; Kurimura, Masayuki; Kurokawa, Katsurou; Nagaoka, Utako; Arawaka, Shigeki; Wada, Manabu; Kawanami, Toru; Kurita, Keiji; Kato, Takeo

    2011-01-01

    The clinical benefits of repetitive transcranial magnetic stimulation (rTMS) for Parkinson's disease (PD) remain controversial. We performed a comprehensive study to examine whether rTMS is a safe and effective treatment for PD. Twelve PD patients received rTMS once a week. The crossover study design consisted of 4-week sham rTMS followed by 4-week real rTMS. The Unified Parkinson's Disease Rating Scale (UPDRS), Modified Hoehn and Yahr Stage, Schwab and England ADL Scale, Actigraph, Mini-Mental State Examination, Hamilton Depression Scale, Wechsler Adult Intelligence Scale-revised, and cerebral blood flow (CBF) and cerebrospinal fluid (CSF) examinations were used to evaluate the rTMS effects. Under both drug-on and drug-off conditions, the real rTMS improved the UPDRS scores significantly, while the sham rTMS did not. There were no significant changes in the results of the neuropsychological tests, CBF and CSF. rTMS seems to be a safe and effective therapeutic option for PD patients, especially in a wearing-off state. PMID:22389830

  2. Innovative treatment approaches in schizophrenia enhancing neuroplasticity: aerobic exercise, erythropoetin and repetitive transcranial magnetic stimulation.

    PubMed

    Wobrock, T; Hasan, A; Falkai, P

    2012-06-01

    Schizophrenia is a brain disorder associated with subtle, but replicable cerebral volume loss mostly prevalent in frontal and temporal brain regions. Post-mortem studies of the hippocampus point to a reduction of the neuropil constituting mainly of synapses associated with changes of molecules mediating plastic responses of neurons during development and learning. Derived from animal studies interventions to enhance neuroplasticity by inducing adult neurogenesis, synaptogenesis, angiogenesis and long-term potentiation (LTP) were developed and the results translated into clinical studies in schizophrenia. Out of these interventions aerobic exercise has been shown to increase hippocampal volume, elevate N-acetyl-aspartate in the hippocampus as neuronal marker, and improve short-term memory in schizophrenia. The hematopoietic growth factor erythropoetin (EPO) is involved in brain development and associated with the production and differentiation of neuronal precursor cells. A first study demonstrated a positive effect of EPO application on cognition in schizophrenia patients. In randomised controlled studies with small sample size, the efficacy of repetitive transcranial magnetic stimulation (rTMS), a biological intervention focussing on the enhancement of LTP, has been shown for the improvement of positive and negative symptoms in schizophrenia,. The putative underlying neurobiological mechanisms of these interventions including the role of neurotrophic factors are outlined and implications for future research regarding neuroprotection strategies to improve schizophrenia are discussed.

  3. Improvements in emotion regulation following repetitive transcranial magnetic stimulation for generalized anxiety disorder.

    PubMed

    Diefenbach, Gretchen J; Assaf, Michal; Goethe, John W; Gueorguieva, Ralitza; Tolin, David F

    2016-10-01

    Generalized anxiety disorder (GAD) is characterized by emotion regulation difficulties, which are associated with abnormalities in neural circuits encompassing fronto-limbic regions including the dorsolateral prefrontal cortex (DLPFC). The aim of this study was to determine whether DLPFC neuromodulation improves emotion regulation in patients with GAD. This is a secondary analysis from a randomized-controlled trial comparing 30 sessions of low-frequency right-sided active (n=13) versus sham (n=12, sham coil) repetitive transcranial magnetic stimulation (rTMS) at the right DLPFC in patients with GAD. Results indicated statistically significant improvements in self-reported emotion regulation difficulties at posttreatment and 3-month follow-up in the active group only. Improvements were found primarily in the domains of goal-directed behaviors and impulse control and were significantly associated with a global clinician rating of improvement. These preliminary results support rTMS as a treatment for GAD and suggest improved emotion regulation as a possible mechanism of change.

  4. Basic principles of transcranial magnetic stimulation (TMS) and repetitive TMS (rTMS).

    PubMed

    Klomjai, Wanalee; Katz, Rose; Lackmy-Vallée, Alexandra

    2015-09-01

    Transcranial magnetic stimulation (TMS) and repetitive TMS (rTMS) are indirect and non-invasive methods used to induce excitability changes in the motor cortex via a wire coil generating a magnetic field that passes through the scalp. Today, TMS has become a key method to investigate brain functioning in humans. Moreover, because rTMS can lead to long-lasting after-effects in the brain, it is thought to be able to induce plasticity. This tool appears to be a potential therapy for neurological and psychiatric diseases. However, the physiological mechanisms underlying the effects induced by TMS and rTMS have not yet been clearly identified. The purpose of the present review is to summarize the main knowledge available for TMS and rTMS to allow for understanding their mode of action and to specify the different parameters that influence their effects. This review takes an inventory of the most-used rTMS paradigms in clinical research and exhibits the hypotheses commonly assumed to explain rTMS after-effects. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  5. Short-term effects of repetitive transcranial magnetic stimulation on sleep bruxism – a pilot study

    PubMed Central

    Zhou, Wei-Na; Fu, Hai-Yang; Du, Yi-Fei; Sun, Jian-Hua; Zhang, Jing-Lu; Wang, Chen; Svensson, Peter; Wang, Ke-Lun

    2016-01-01

    The purpose of this study was to investigate the effects of repetitive transcranial magnetic stimulation (rTMS) on patients with sleep bruxism (SB). Twelve patients with SB were included in an open, single-intervention pilot study. rTMS at 1 Hz and an intensity of 80% of the active motor threshold was applied to the ‘hot spot' of the masseter muscle representation at the primary motor cortex bilaterally for 20 min per side each day for 5 consecutive days. The jaw-closing muscle electromyographic (EMG) activity during sleep was recorded with a portable EMG recorder at baseline, during rTMS treatment and at follow-up for 5 days. In addition, patients scored their jaw-closing muscle soreness on a 0–10 numerical rating scale (NRS). Data were analysed with analysis of variance. The intensity of the EMG activity was suppressed during and after rTMS compared to the baseline (P = 0.04; P = 0.02, respectively). The NRS score of soreness decreased significantly during and after rTMS compared with baseline (P < 0.01). These findings indicated a significant inhibition of jaw-closing muscle activity during sleep along with a decrease of muscle soreness. This pilot study raises the possibility of therapeutic benefits from rTMS in patients with bruxism and calls for further and more controlled studies. PMID:27025267

  6. Long-lasting repetitive transcranial magnetic stimulation modulates electroencephalography oscillation in patients with disorders of consciousness.

    PubMed

    Xia, Xiaoyu; Liu, Yang; Bai, Yang; Liu, Ziyuan; Yang, Yi; Guo, Yongkun; Xu, Ruxiang; Gao, Xiaorong; Li, Xiaoli; He, Jianghong

    2017-10-18

    Repetitive transcranial magnetic stimulation (rTMS) has been applied for the treatment of patients with disorders of consciousness (DOC). Timely and accurate assessments of its modulation effects are very useful. This study evaluated rTMS modulation effects on electroencephalography (EEG) oscillation in patients with chronic DOC. Eighteen patients with a diagnosis of DOC lasting more than 3 months were recruited. All patients received one session of 10-Hz rTMS at the left dorsolateral prefrontal cortex and then 12 of them received consecutive rTMS treatment everyday for 20 consecutive days. Resting-state EEGs were recorded before the experiment (T0) after one session of rTMS (T1) and after the entire treatment (T2). The JFK Coma Recovery Scale-Revised scale scores were also recorded at the time points. Our data showed that application of 10-Hz rTMS to the left dorsolateral prefrontal cortex decreased low-frequency band power and increased high-frequency band power in DOC patients, especially in minimal conscious state patients. Considering the correlation of the EEG spectrum with the consciousness level of patients with DOC, quantitative EEG might be useful for assessment of the effect of rTMS in DOC patients.

  7. The cerebellum in emotion regulation: a repetitive transcranial magnetic stimulation study.

    PubMed

    Schutter, Dennis J L G; van Honk, Jack

    2009-03-01

    Several lines of evidence suggest that the cerebellum may play a role in the regulation of emotion. The aim of this study was to investigate the hypothesis that inhibition of cerebellar function using slow repetitive transcranial magnetic stimulation (rTMS) would lead to increased negative mood as a result of impaired emotion regulation. In a randomized counterbalanced within-subjects design, 12 healthy young right-handed volunteers received 20 min of cerebellar, occipital, or sham 1 Hz rTMS on three separate days. Mood state inventories were acquired prior to and immediately after rTMS and after an emotion regulation task (ERT). In the ERT, participants were instructed to either look at aversive and neutral scenes, or to suppress the negative feelings experienced while watching aversive scenes during which the electroencephalogram (EEG) was recorded. Results showing no changes in baseline-corrected mood were observed immediately after rTMS. However, significant increases in baseline-corrected negative mood following the ERT were reported after cerebellar rTMS exclusively. No effects on the EEG during the ERT were observed. These findings provide support for the view that the cerebellum is implicated in the regulation of emotion and mood, and concur with evidence of cerebellar abnormalities observed in disorders associated with emotion dysregulation. In order to clarify the underlying biological mechanisms involved, more research is needed.

  8. The effects of repetitive transcranial magnetic stimulation in an animal model of tinnitus

    PubMed Central

    Mulders, Wilhelmina H. A. M.; Vooys, Vanessa; Makowiecki, Kalina; Tang, Alex D.; Rodger, Jennifer

    2016-01-01

    Tinnitus (phantom auditory perception associated with hearing loss) can seriously affect wellbeing. Its neural substrate is unknown however it has been linked with abnormal activity in auditory pathways. Though no cure currently exists, repetitive transcranial magnetic stimulation (rTMS) has been shown to reduce tinnitus in some patients, possibly via induction of cortical plasticity involving brain derived neurotrophic factor (BDNF). We examined whether low intensity rTMS (LI-rTMS) alleviates signs of tinnitus in a guinea pig model and whether this involves changes in BDNF expression and hyperactivity in inferior colliculus. Acoustic trauma was used to evoke hearing loss, central hyperactivity and tinnitus. When animals developed tinnitus, treatment commenced (10 sessions of 10 minutes 1 Hz LI-rTMS or sham over auditory cortex over 14 days). After treatment ceased animals were tested for tinnitus, underwent single-neuron recordings in inferior colliculus to assess hyperactivity and samples from cortex and inferior colliculus were taken for BDNF ELISA. Analysis revealed a significant reduction of tinnitus after LI-rTMS compared to sham, without a statistical significant effect on BDNF levels or hyperactivity. This suggests that LI-rTMS alleviates behavioural signs of tinnitus by a mechanism independent of inferior colliculus hyperactivity and BDNF levels and opens novel therapeutic avenues for tinnitus treatment. PMID:27905540

  9. Disruption of saccadic adaptation with repetitive transcranial magnetic stimulation of the posterior cerebellum in humans.

    PubMed

    Jenkinson, Ned; Miall, R Chris

    2010-12-01

    Saccadic eye movements are driven by motor commands that are continuously modified so that errors created by eye muscle fatigue, injury, or-in humans-wearing spectacles can be corrected. It is possible to rapidly adapt saccades in the laboratory by introducing a discrepancy between the intended and actual saccadic target. Neurophysiological and lesion studies in the non-human primate as well as neuroimaging and patient studies in humans have demonstrated that the oculomotor vermis (lobules VI and VII of the posterior cerebellum) is critical for saccadic adaptation. We studied the effect of transiently disrupting the function of posterior cerebellum with repetitive transcranial magnetic stimulation (rTMS) on the ability of healthy human subjects to adapt saccadic eye movements. rTMS significantly impaired the adaptation of the amplitude of saccades, without modulating saccadic amplitude or variability in baseline conditions. Moreover, increasing the intensity of rTMS produced a larger impairment in the ability to adapt saccadic size. These results provide direct evidence for the role of the posterior cerebellum in man and further evidence that TMS can modulate cerebellar function.

  10. Effect of repetitive transcranial magnetic stimulation on mood in healthy subjects

    PubMed Central

    Moulier, Virginie; Gaudeau-Bosma, Christian; Isaac, Clémence; Allard, Anne-Camille; Bouaziz, Noomane; Sidhoumi, Djedia; Braha-Zeitoun, Sonia; Benadhira, René; Thomas, Fanny; Januel, Dominique

    2016-01-01

    Background High frequency repetitive transcranial magnetic stimulation (rTMS) of the left dorsolateral prefrontal cortex (DLPFC) has shown significant efficiency in the treatment of resistant depression. However in healthy subjects, the effects of rTMS remain unclear. Objective Our aim was to determine the impact of 10 sessions of rTMS applied to the DLPFC on mood and emotion recognition in healthy subjects. Design In a randomised double-blind study, 20 subjects received 10 daily sessions of active (10 Hz frequency) or sham rTMS. The TMS coil was positioned on the left DLPFC through neuronavigation. Several dimensions of mood and emotion processing were assessed at baseline and after rTMS with clinical scales, visual analogue scales (VASs), and the Ekman 60 faces test. Results The 10 rTMS sessions targeting the DLPFC were well tolerated. No significant difference was found between the active group and the control group for clinical scales and the Ekman 60 faces test. Compared to the control group, the active rTMS group presented a significant improvement in their adaptation to daily life, which was assessed through VAS. Conclusion This study did not show any deleterious effect on mood and emotion recognition of 10 sessions of rTMS applied on the DLPFC in healthy subjects. This study also suggested a positive effect of rTMS on quality of life. PMID:26993786

  11. Complex repetitive behavior: punding after bilateral subthalamic nucleus stimulation in Parkinson's disease.

    PubMed

    Pallanti, Stefano; Bernardi, Silvia; Raglione, Laura Maria; Marini, Paolo; Ammannati, Franco; Sorbi, Sandro; Ramat, Silvia

    2010-07-01

    "Punding" is the term used to describe a stereotyped motor behavior characterized by an intense fascination with repetitive purposeless movements, such as taking apart mechanical objects, handling common objects as if they were new and entertaining, constantly picking at oneself, etc. As a phenomenon with both impulsive and compulsive features, the phenomenology of punding is currently being questioned. In order to investigate the pathophysiology of this phenomenon, we screened a population of Parkinson's disease (PD) outpatients who underwent subthalamic nucleus deep brain stimulation (STN DBS). We conducted a patient-and-relative-completed survey with 24 consecutive patients in an academic outpatient care center, using a modified version of a structured interview. Patients were administered the Unified Parkinson's Disease Rating Scale (UPDRS), the Obsessive-Compulsive Inventory and the Sheehan Disability Scale. Five (20.8%) of the 24 subjects were identified as punders, including three men (60%) and two women. The punders were comparable to the non-punders in terms of clinical and demographic factors. The punder and non-punder groups only differed statistically with regard to the length of time from DBS implantation. Those findings suggest that punding might be induced by STN DBS, and its rate of occurrence in DBS population seems to be more common than previously suspected. Copyright 2010 Elsevier Ltd. All rights reserved.

  12. Amodal semantic representations depend on both anterior temporal lobes: evidence from repetitive transcranial magnetic stimulation.

    PubMed

    Pobric, Gorana; Jefferies, Elizabeth; Ralph, Matthew A Lambon

    2010-04-01

    The key question of how the brain codes the meaning of words and pictures is the focus of vigorous debate. Is there a "semantic hub" in the temporal poles where these different inputs converge to form amodal conceptual representations? Alternatively, are there distinct neural circuits that underpin our comprehension of pictures and words? Understanding words might be primarily left-lateralised, linked to other language areas, while semantic representation of pictures may be more bilateral. To elucidate this debate, we used offline, low-frequency, repetitive transcranial magnetic stimulation (rTMS) to disrupt neural processing temporarily in the left or right temporal poles. During the induced refractory period, participants made judgements of semantic association for verbal and pictorial stimuli. The efficiency of semantic processing was reduced by rTMS, yet a perceptual task of comparable difficulty was unaffected. rTMS applied to the left or right temporal poles disrupted semantic processing for words and pictures to the same degree, while rTMS delivered at a control site had no impact. The results confirm that both temporal poles form a critical substrate within the neural network that supports conceptual knowledge, regardless of modality.

  13. Noninvasive Brain Stimulation With High-Frequency and Low-Intensity Repetitive Transcranial Magnetic Stimulation Treatment for Posttraumatic Stress Disorder

    PubMed Central

    Boggio, Paulo Sergio; Rocha, Martha; Oliveira, Maira Okada; Fecteau, Shirley; Cohen, Roni B.; Campanhã, Camila; Ferreira-Santos, Eduardo; Meleiro, Alexandrina; Corchs, Felipe; Zaghi, Soroush; Pascual-Leone, Alvaro; Fregni, Felipe

    2011-01-01

    Objective We aimed to investigate the efficacy of 20 Hz repetitive transcranial magnetic stimulation (rTMS) of either right or left dorsolateral prefrontal cortex (DLPFC) as compared to sham rTMS for the relief of posttraumatic stress disorder (PTSD)–associated symptoms. Method In this double-blind, placebo-controlled phase II trial conducted between October 2005 and July 2008, 30 patients with DSM-IV–diagnosed PTSD were randomly assigned to receive 1 of the following treatments: active 20 Hz rTMS of the right DLPFC, active 20 Hz rTMS of the left DLPFC, or sham rTMS. Treatments were administered in 10 daily sessions over 2 weeks. A blinded rater assessed severity of core PTSD symptoms, depression, and anxiety before, during, and after completion of the treatment protocol. In addition, a battery of neuropsychological tests was measured before and after treatment. Results Results show that both active conditions—20 Hz rTMS of left and right DLPFC—induced a significant decrease in PTSD symptoms as indexed by the PTSD Checklist and Treatment Outcome PTSD Scale; however, right rTMS induced a larger effect as compared to left rTMS. In addition, there was a significant improvement of mood after left rTMS and a significant reduction of anxiety following right rTMS. Improvements in PTSD symptoms were long lasting; effects were still significant at the 3-month follow-up. Finally, neuropsychological evaluation showed that active 20 Hz rTMS is not associated with cognitive worsening and is safe for use in patients with PTSD. Conclusions These results support the notion that modulation of prefrontal cortex can alleviate the core symptoms of PTSD and suggest that high-frequency rTMS of right DLPFC might be the optimal treatment strategy. PMID:20051219

  14. Noninvasive brain stimulation with high-frequency and low-intensity repetitive transcranial magnetic stimulation treatment for posttraumatic stress disorder.

    PubMed

    Boggio, Paulo Sergio; Rocha, Martha; Oliveira, Maira Okada; Fecteau, Shirley; Cohen, Roni B; Campanhã, Camila; Ferreira-Santos, Eduardo; Meleiro, Alexandrina; Corchs, Felipe; Zaghi, Soroush; Pascual-Leone, Alvaro; Fregni, Felipe

    2010-08-01

    We aimed to investigate the efficacy of 20 Hz repetitive transcranial magnetic stimulation (rTMS) of either right or left dorsolateral prefrontal cortex (DLPFC) as compared to sham rTMS for the relief of posttraumatic stress disorder (PTSD)-associated symptoms. In this double-blind, placebo-controlled phase II trial conducted between October 2005 and July 2008, 30 patients with DSM-IV-diagnosed PTSD were randomly assigned to receive 1 of the following treatments: active 20 Hz rTMS of the right DLPFC, active 20 Hz rTMS of the left DLPFC, or sham rTMS. Treatments were administered in 10 daily sessions over 2 weeks. A blinded rater assessed severity of core PTSD symptoms, depression, and anxiety before, during, and after completion of the treatment protocol. In addition, a battery of neuropsychological tests was measured before and after treatment. Results show that both active conditions-20 Hz rTMS of left and right DLPFC-induced a significant decrease in PTSD symptoms as indexed by the PTSD Checklist and Treatment Outcome PTSD Scale; however, right rTMS induced a larger effect as compared to left rTMS. In addition, there was a significant improvement of mood after left rTMS and a significant reduction of anxiety following right rTMS. Improvements in PTSD symptoms were long lasting; effects were still significant at the 3-month follow-up. Finally, neuropsychological evaluation showed that active 20 Hz rTMS is not associated with cognitive worsening and is safe for use in patients with PTSD. These results support the notion that modulation of prefrontal cortex can alleviate the core symptoms of PTSD and suggest that high-frequency rTMS of right DLPFC might be the optimal treatment strategy. Copyright 2010 Physicians Postgraduate Press, Inc.

  15. Impact of Repetitive Transcranial Magnetic Stimulation (rTMS) on Brain Functional Marker of Auditory Hallucinations in Schizophrenia Patients

    PubMed Central

    Maïza, Olivier; Hervé, Pierre-Yve; Etard, Olivier; Razafimandimby, Annick; Montagne-Larmurier, Aurélie; Dollfus, Sonia

    2013-01-01

    Several cross-sectional functional Magnetic Resonance Imaging (fMRI) studies reported a negative correlation between auditory verbal hallucination (AVH) severity and amplitude of the activations during language tasks. The present study assessed the time course of this correlation and its possible structural underpinnings by combining structural, functional MRI and repetitive Transcranial Magnetic Stimulation (rTMS). Methods: Nine schizophrenia patients with AVH (evaluated with the Auditory Hallucination Rating scale; AHRS) and nine healthy participants underwent two sessions of an fMRI speech listening paradigm. Meanwhile, patients received high frequency (20 Hz) rTMS. Results: Before rTMS, activations were negatively correlated with AHRS in a left posterior superior temporal sulcus (pSTS) cluster, considered henceforward as a functional region of interest (fROI). After rTMS, activations in this fROI no longer correlated with AHRS. This decoupling was explained by a significant decrease of AHRS scores after rTMS that contrasted with a relative stability of cerebral activations. A voxel-based-morphometry analysis evidenced a cluster of the left pSTS where grey matter volume negatively correlated with AHRS before rTMS and positively correlated with activations in the fROI at both sessions. Conclusion: rTMS decreases the severity of AVH leading to modify the functional correlate of AVH underlain by grey matter abnormalities. PMID:24961421

  16. Effect of Repetitive Transcranial Magnetic Stimulation on fMRI Resting-State Connectivity in Multiple System Atrophy

    PubMed Central

    Chou, Ying-hui; Zhao, Yan-Ping; Hou, Bo; Feng, Feng

    2015-01-01

    Abstract Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive neuromodulation technique that has been used to treat neurological and psychiatric conditions. Although results of rTMS intervention are promising, so far, little is known about the rTMS effect on brain functional networks in clinical populations. In this study, we used a whole-brain connectivity analysis of resting-state functional magnetic resonance imaging data to uncover changes in functional connectivity following rTMS intervention and their association with motor symptoms in patients with multiple system atrophy (MSA). Patients were randomized to active rTMS or sham rTMS groups and completed a 10-session 5-Hz rTMS treatment over the left primary motor area. The results showed significant rTMS-related changes in motor symptoms and functional connectivity. Specifically, (1) significant improvement of motor symptoms was observed in the active rTMS group, but not in the sham rTMS group; and (2) several functional links involving the default mode, cerebellar, and limbic networks exhibited positive changes in functional connectivity in the active rTMS group. Moreover, the positive changes in functional connectivity were associated with improvement in motor symptoms for the active rTMS group. The present findings suggest that rTMS may improve motor symptoms by modulating functional links connecting to the default mode, cerebellar, and limbic networks, inferring a future therapeutic candidate for patients with MSA. PMID:25786196

  17. A Randomised Controlled Trial of Neuronavigated Repetitive Transcranial Magnetic Stimulation (rTMS) in Anorexia Nervosa

    PubMed Central

    McClelland, Jessica; Kekic, Maria; Bozhilova, Natali; Nestler, Steffen; Dew, Tracy; Van den Eynde, Frederique; David, Anthony S.; Rubia, Katya; Campbell, Iain C.; Schmidt, Ulrike

    2016-01-01

    Background Anorexia nervosa (AN) is associated with morbid fear of fatness, extreme food restriction and altered self-regulation. Neuroimaging data implicate fronto-striatal circuitry, including the dorsolateral prefrontal cortex (DLPFC). Methods In this double-blind parallel group study, we investigated the effects of one session of sham-controlled high-frequency repetitive transcranial magnetic stimulation (rTMS) to the left DLPFC (l-DLPFC) in 60 individuals with AN. A food exposure task was administered before and after the procedure to elicit AN-related symptoms. Outcomes The primary outcome measure was ‘core AN symptoms’, a variable which combined several subjective AN-related experiences. The effects of rTMS on other measures of psychopathology (e.g. mood), temporal discounting (TD; intertemporal choice behaviour) and on salivary cortisol concentrations were also investigated. Safety, tolerability and acceptability were assessed. Results Fourty-nine participants completed the study. Whilst there were no interaction effects of rTMS on core AN symptoms, there was a trend for group differences (p = 0.056): after controlling for pre-rTMS scores, individuals who received real rTMS had reduced symptoms post-rTMS and at 24-hour follow-up, relative to those who received sham stimulation. Other psychopathology was not altered differentially following real/sham rTMS. In relation to TD, there was an interaction trend (p = 0.060): real versus sham rTMS resulted in reduced rates of TD (more reflective choice behaviour). Salivary cortisol concentrations were unchanged by stimulation. rTMS was safe, well–tolerated and was considered an acceptable intervention. Conclusions This study provides modest evidence that rTMS to the l-DLPFC transiently reduces core symptoms of AN and encourages prudent decision making. Importantly, individuals with AN considered rTMS to be a viable treatment option. These findings require replication in multiple-session studies to evaluate

  18. Repetitive Transcranial Magnetic Stimulation (rTMS) Therapy in Parkinson Disease: A Meta-Analysis.

    PubMed

    Wagle Shukla, Aparna; Shuster, Jonathan J; Chung, Jae Woo; Vaillancourt, David E; Patten, Carolynn; Ostrem, Jill; Okun, Michael S

    2016-04-01

    Several studies have reported repetitive transcranial magnetic stimulation (rTMS) therapy as an effective treatment for the control of motor symptoms in Parkinson disease. The objective of the study is to quantify the overall efficacy of this treatment. Systematic review and meta-analysis. We reviewed the literature on clinical rTMS trials in Parkinson disease since the technique was introduced in 1980. We used the following databases: MEDLINE, Web of Science, Cochrane, and CINAHL. Patients with Parkinson disease who were participating in prospective clinical trials that included an active arm and a control arm and change in motor scores on Unified Parkinson's Disease Rating Scale as the primary outcome. We pooled data from 21 studies that met these criteria. We then analyzed separately the effects of low- and high-frequency rTMS on clinical motor improvements. The overall pooled mean difference between treatment and control groups in the Unified Parkinson's Disease Rating Scale motor score was significant (4.0 points, 95% confidence interval, 1.5, 6.7; P = .005). rTMS therapy was effective when low-frequency stimulation (≤ 1 Hz) was used with a pooled mean difference of 3.3 points (95% confidence interval 1.6, 5.0; P = .005). There was a trend for significance when high-frequency stimulation (≥ 5 Hz) studies were evaluated with a pooled mean difference of 3.9 points (95% confidence interval, -0.7, 8.5; P = .08). rTMS therapy demonstrated benefits at short-term follow-up (immediately after a treatment protocol) with a pooled mean difference of 3.4 points (95% confidence interval, 0.3, 6.6; P = .03) as well as at long-term follow-up (average follow-up 6 weeks) with mean difference of 4.1 points (95% confidence interval, -0.15, 8.4; P = .05). There were insufficient data to statistically analyze the effects of rTMS when we specifically examined bradykinesia, gait, and levodopa-induced dyskinesia using quantitative methods. rTMS therapy in patients with Parkinson

  19. Safety study of 50 Hz repetitive transcranial magnetic stimulation in patients with Parkinson’s disease

    PubMed Central

    Benninger, David H.; Lomarev, Mikhail; Wassermann, Eric; Lopez, Grisel; Houdayer, Elise; Fasano, Rebecca E.; Dang, Nguyet; Hallett, Mark

    2009-01-01

    Objective Repetitive transcranial magnetic stimulation (rTMS) has shown promising results in treating Parkinson’s disease (PD), but the best values for rTMS parameters are not established. 50 Hz rTMS may be superior to ≤ 25 Hz rTMS investigated so far. The objective of this study was to determine if 50 Hz rTMS could be delivered safely in PD patients since current safety limits are exceeded. Methods 50 Hz rTMS was applied with a circular coil on the primary motor cortex (M1). Stimulation intensity was first tested at 60% rest motor threshold [RMT] and 0.5 sec train duration and then increased in 0.5 sec steps to 2 sec, and by 10% steps to 90% RMT. Multi-channel electromyography (EMG) was recorded to control for signs of increasing time-locked EMG activity including correlates of the spread of excitation and after-discharges, or an increase of M1 excitability. Pre- and post-50 Hz rTMS assessments included EEG, Unified Parkinson Disease Rating Scale (UPDRS), Grooved Pegboard Test, Serial Reaction Time Task (SRTT), Folstein Mini-Mental Status Examination (MMSE) and Verbal Fluency to control for motor and cognitive side effects. Results Ten PD patients were investigated. Multi-channel EMG showed no signs of increased time-locked EMG activity including correlates of the spread of excitation and after-discharges, or increased M1 excitability in 9 patients. A PD patient with bi-temporal spikes in the pre-testing EEG had clinical and EMG correlates of spread of excitation at 90% RMT, but no seizure activity. Pre- and post-50 Hz assessment showed no changes. No adverse events were observed. 50 Hz rTMS was well tolerated except by one patient who wished to terminate the study due to facial muscle stimulation. Conclusion 50 Hz rTMS at an intensity of 90% RMT for 2 sec appears safe in patients with PD, but caution should be taken for patients with paroxysmal EEG activity. For this reason, comprehensive screening should include EEG before higher-frequency rTMS is applied

  20. Effects of repetitive transcranial magnetic stimulation in performing eye-hand integration tasks: four preliminary studies with children showing low-functioning autism.

    PubMed

    Panerai, Simonetta; Tasca, Domenica; Lanuzza, Bartolo; Trubia, Grazia; Ferri, Raffaele; Musso, Sabrina; Alagona, Giovanna; Di Guardo, Giuseppe; Barone, Concetta; Gaglione, Maria P; Elia, Maurizio

    2014-08-01

    This report, based on four studies with children with low-functioning autism, aimed at evaluating the effects of repetitive transcranial magnetic stimulation delivered on the left and right premotor cortices on eye-hand integration tasks; defining the long-lasting effects of high-frequency repetitive transcranial magnetic stimulation; and investigating the real efficacy of high-frequency repetitive transcranial magnetic stimulation by comparing three kinds of treatments (high-frequency repetitive transcranial magnetic stimulation, a traditional eye-hand integration training, and both treatments combined). Results showed a significant increase in eye-hand performances only when high-frequency repetitive transcranial magnetic stimulation was delivered on the left premotor cortex; a persistent improvement up to 1 h after the end of the stimulation; better outcomes in the treatment combining high-frequency repetitive transcranial magnetic stimulation and eye-hand integration training. Based on these preliminary findings, further evaluations on the usefulness of high-frequency repetitive transcranial magnetic stimulation in rehabilitation of children with autism are strongly recommended.

  1. Increases in frontostriatal connectivity are associated with response to dorsomedial repetitive transcranial magnetic stimulation in refractory binge/purge behaviors

    PubMed Central

    Dunlop, Katharine; Woodside, Blake; Lam, Eileen; Olmsted, Marion; Colton, Patricia; Giacobbe, Peter; Downar, Jonathan

    2015-01-01

    Background Conventional treatments for eating disorders are associated with poor response rates and frequent relapse. Novel treatments are needed, in combination with markers to characterize and predict treatment response. Here, resting-state functional magnetic resonance imaging (rs-fMRI) was used to identify predictors and correlates of response to repetitive transcranial magnetic stimulation (rTMS) of the dorsomedial prefrontal cortex (dmPFC) at 10 Hz for eating disorders with refractory binge/purge symptomatology. Methods 28 subjects with anorexia nervosa, binge−purge subtype or bulimia nervosa underwent 20–30 sessions of 10 Hz dmPFC rTMS. rs-fMRI data were collected before and after rTMS. Subjects were stratified into responder and nonresponder groups using a criterion of ≥50% reduction in weekly binge/purge frequency. Neural predictors and correlates of response were identified using seed-based functional connectivity (FC), using the dmPFC and adjacent dorsal anterior cingulate cortex (dACC) as regions of interest. Results 16 of 28 subjects met response criteria. Treatment responders had lower baseline FC from dmPFC to lateral orbitofrontal cortex and right posterior insula, and from dACC to right posterior insula and hippocampus. Responders had low baseline FC from the dACC to the ventral striatum and anterior insula; this connectivity increased over treatment. However, in nonresponders, frontostriatal FC was high at baseline, and dmPFC-rTMS suppressed FC in association with symptomatic worsening. Conclusions Enhanced frontostriatal connectivity was associated with responders to dmPFC-rTMS for binge/purge behavior. rTMS caused paradoxical suppression of frontostriatal connectivity in nonresponders. rs-fMRI could prove critical for optimizing stimulation parameters in a future sham-controlled trial of rTMS in disordered eating. PMID:26199873

  2. Increased cerebellar activation after repetitive transcranial magnetic stimulation over the primary motor cortex in patients with multiple system atrophy

    PubMed Central

    Li, Linling; Wu, Tianxia; Hou, Bo; Wu, Shuang; Feng, Feng; Cui, Liying

    2016-01-01

    Background Previous review reported that the high-frequency repetitive transcranial magnetic stimulation (rTMS) over the primary motor area (M1) of Parkinson’s disease (PD) patients could alleviate their symptoms. This study aimed to investigate the effect of rTMS over the left M1 of patients with multiple system atrophy (MSA). Methods Fifteen MSA patients were randomly assigned to receive a 10-session real (EP: group of experimental patients; n=7) or sham (CP: group of control patients; n=8) rTMS stimulation over two weeks. The overall experimental procedure consisted of two functional magnetic resonance imaging (fMRI) sessions, before and after a 10-session rTMS treatment. A complex self-paced sequential tapping task was performed during fMRI scanning. In addition, 18 age and gender matched healthy controls (HC) were enrolled. Subjects from the HC group did not receive any rTMS treatment and they underwent fMRI examination only once. The primary end point was the motor score change of the Unified Multiple System Atrophy Rating Scale (UMSARS-II) measured before and after the 5th and 10th session. Task-related activation was also compared among groups. Results After active rTMS treatment, only patients of EP group significant improvement in UMSARS-II score. Compared to HC, MSA patients showed significant activation over similar brain areas except for the cerebellum. Increased activation was obtained in the bilateral cerebellum after rTMS treatment in the EP group. On the contrary, no increased activation was identified in the CP group. Conclusions Our results highlight rTMS over M1 induced motor improvement in MSA patients that may be associated with increased activation in the cerebellum. PMID:27127756

  3. Preliminary guidelines for safe and effective use of repetitive transcranial magnetic stimulation in moderate to severe traumatic brain injury.

    PubMed

    Nielson, Dylan M; McKnight, Curtis A; Patel, Riddhi N; Kalnin, Andrew J; Mysiw, Walter J

    2015-04-01

    Transcranial magnetic stimulation has generated extensive interest within the traumatic brain injury (TBI) rehabilitation community, but little work has been done with repetitive protocols, which can produce prolonged changes in behavior. This is partly because of concerns about the safety of repetitive transcranial magnetic stimulation (rTMS) in subjects with TBI, particularly the risk of seizures. These risks can be minimized by careful selection of the rTMS protocol and exclusion criteria. In this article, we identify guidelines for safe use of rTMS in subjects with TBI based on a review of the literature and illustrate their application with a case study. Our subject is a 48-year-old man who sustained a severe TBI 5 years prior to beginning rTMS for the treatment of post-TBI depression. After a 4-week baseline period, we administered daily sessions of low-frequency stimulation to the right dorsolateral prefrontal cortex for 6 weeks. After stimulation, we performed monthly assessments for 3 months. The Hamilton Depression Rating Scale (HAMD) was our primary outcome measure. The stimulation was well tolerated and the patient reported no side effects. After 6 weeks of stimulation, the patient's depression was slightly improved, and these improvements continued through follow-up. At the end of follow-up, the patient's HAMD score was 49% of the average baseline score.

  4. Effects of low-frequency repetitive transcranial magnetic stimulation and neuromuscular electrical stimulation on upper extremity motor recovery in the early period after stroke: a preliminary study.

    PubMed

    Tosun, Aliye; Türe, Sabiha; Askin, Ayhan; Yardimci, Engin Ugur; Demirdal, Secil Umit; Kurt Incesu, Tülay; Tosun, Ozgur; Kocyigit, Hikmet; Akhan, Galip; Gelal, Fazıl Mustafa

    2017-07-01

    To assess the efficacy of inhibitory repetitive transcranial magnetic stimulation (rTMS) and neuromuscular electrical stimulation (NMES) on upper extremity motor function in patients with acute/subacute ischemic stroke. Twenty-five ischemic acute/subacute stroke subjects were enrolled in this randomized controlled trial. Experimental group 1 received low frequency (LF) rTMS to the primary motor cortex of the unaffected side + physical therapy (PT) including activities to improve strength, flexibility, transfers, posture, balance, coordination, and activities of daily living, mainly focusing on upper limb movements; experimental group 2 received the same protocol combined with NMES to hand extensor muscles; and the control group received only PT. Functional magnetic resonance imaging (fMRI) scan was used to evaluate the activation or inhibition of the affected and unaffected primary motor cortex. No adverse effect was reported. Most of the clinical outcome scores improved significantly in all groups, however no statistically significant difference was found between groups due to the small sample sizes. The highest percent improvement scores were observed in TMS + NMES group (varying between 48 and 99.3%) and the lowest scores in control group (varying between 13.1 and 28.1%). Hand motor recovery was significant in both experimental groups while it did not change in control group. Some motor cortex excitability changes were also observed in fMRI. LF-rTMS with or without NMES seems to facilitate the motor recovery in the paretic hand of patients with acute/subacute ischemic stroke. TMS or the combination of TMS + NMES may be a promising additional therapy in upper limb motor training. Further studies with larger numbers of patients are needed to establish their effectiveness in upper limb motor rehabilitation of stroke.

  5. Repetitive Transcranial Magnetic Stimulation for Treatment-Resistant Depression: An Economic Analysis

    PubMed Central

    Tu, Hong Anh; Palimaka, Stefan; Sehatzadeh, Shayan; Blackhouse, Gord; Yap, Belinda; Tsoi, Bernice; Bowen, Jim; O'Reilly, Daria; Holubowich, Corinne; Kaulback, Kellee; Campbell, Kaitryn

    2016-01-01

    Background Major depressive disorder (MDD, 10% over a person's lifetime) is common and costly to the health system. Unfortunately, many MDD cases are resistant to treatment with antidepressant drugs and require other treatment to reduce or eliminate depression. Electroconvulsive therapy (ECT) has long been used to treat persons with treatment-resistant depression (TRD). Despite its effectiveness, ECT has side effects that make patients intolerant to the treatment, or they refuse to use it. Repetitive transcranial magnetic stimulation (rTMS), which has fewer side effects than ECT and might be an alternative for TRD patients who are ineligible for or unwilling to undergo ECT, has been developed to treat TRD. Objectives This analysis evaluates the cost-effectiveness of rTMS for patients with TRD compared with ECT or sham rTMS and estimates the potential budgetary impact of various levels of implementation of rTMS in Ontario. Review Methods A cost-utility analysis compared the costs and health outcomes of two treatments for persons with TRD in Ontario: rTMS alone compared with ECT alone and rTMS alone compared with sham rTMS. We calculated the six-month incremental costs and quality-adjusted life-years (QALYs) for these treatments. One-way and probabilistic sensitivity analyses were performed to test the robustness of the model's results. A 1-year budget impact analysis estimated the costs of providing funding for rTMS. The base-case analysis examined the additional costs for funding six centres, where rTMS infrastructure is in place. Sensitivity and scenario analyses explored the impact of increasing diffusion of rTMS to centres with existing ECT infrastructure. All analyses were conducted from the Ontario health care payer perspective. Results ECT was cost effective compared to rTMS when the willingness to pay is greater than $37,640.66 per QALY. In the base-case analysis, which had a six-month time horizon, the cost and effectiveness for rTMS was $5,272 and 0

  6. Accelerometer-based automatic voice onset detection in speech mapping with navigated repetitive transcranial magnetic stimulation.

    PubMed

    Vitikainen, Anne-Mari; Mäkelä, Elina; Lioumis, Pantelis; Jousmäki, Veikko; Mäkelä, Jyrki P

    2015-09-30

    The use of navigated repetitive transcranial magnetic stimulation (rTMS) in mapping of speech-related brain areas has recently shown to be useful in preoperative workflow of epilepsy and tumor patients. However, substantial inter- and intraobserver variability and non-optimal replicability of the rTMS results have been reported, and a need for additional development of the methodology is recognized. In TMS motor cortex mappings the evoked responses can be quantitatively monitored by electromyographic recordings; however, no such easily available setup exists for speech mappings. We present an accelerometer-based setup for detection of vocalization-related larynx vibrations combined with an automatic routine for voice onset detection for rTMS speech mapping applying naming. The results produced by the automatic routine were compared with the manually reviewed video-recordings. The new method was applied in the routine navigated rTMS speech mapping for 12 consecutive patients during preoperative workup for epilepsy or tumor surgery. The automatic routine correctly detected 96% of the voice onsets, resulting in 96% sensitivity and 71% specificity. Majority (63%) of the misdetections were related to visible throat movements, extra voices before the response, or delayed naming of the previous stimuli. The no-response errors were correctly detected in 88% of events. The proposed setup for automatic detection of voice onsets provides quantitative additional data for analysis of the rTMS-induced speech response modifications. The objectively defined speech response latencies increase the repeatability, reliability and stratification of the rTMS results. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Low-frequency repetitive transcranial magnetic stimulation for dyskinesia and motor performance in Parkinson's disease.

    PubMed

    Sayın, Sevgi; Cakmur, Raif; Yener, Görsev G; Yaka, Erdem; Uğurel, Burcu; Uzunel, Fatma

    2014-08-01

    Dyskinesias are one of the most frequent and disabling complications of the long-term treatment of Parkinson's disease (PD). Although the cause is not completely understood, it appears that an imbalance between excitatory and inhibitory inputs from the basal ganglia to the motor cortex leads to overactivation of motor and premotor areas. Overactivation of the supplementary motor area (SMA) has been observed in neuroimaging studies in dyskinetic PD patients. We investigated the effects of low-frequency repetitive transcranial magnetic stimulation (rTMS) of the SMA on levodopa-induced dyskinesias (LID) and motor performance in PD. We tested whether longer duration (10days) and higher number of total pulses (1800 pulses) would enhance the beneficial effect. Seventeen dyskinetic PD patients were randomly assigned to real rTMS or sham (placebo) rTMS, and 1Hz rTMS or sham rTMS was applied over the SMA for 10 consecutive days. Patients were assessed at baseline and 1day after the last rTMS with a levodopa challenge test, and video recordings were taken. Dyskinesias and motor performance were rated off-line by two blinded raters using video recordings. After 10days of treatment with rTMS, we observed that 1Hz rTMS delivered over the SMA had decreased LID lasting for 24hours without a change in motor performance, whereas sham rTMS induced no significant change in dyskinesia scores. These results support a possible therapeutic effect of low-frequency rTMS in LID. However, in order to suggest rTMS as an effective treatment, long-term observations and further investigations with a larger patient population are essential.

  8. Tibialis anterior stretch reflex in early stance is suppressed by repetitive transcranial magnetic stimulation

    PubMed Central

    Zuur, Abraham T; Christensen, Mark S; Sinkjær, Thomas; Grey, Michael J; Nielsen, Jens Bo

    2009-01-01

    A rapid plantar flexion perturbation in the early stance phase of walking elicits a large stretch reflex in tibialis anterior (TA). In this study we use repetitive transcranial magnetic stimulation (rTMS) to test if this response is mediated through a transcortical pathway. TA stretch reflexes were elicited in the early stance phase of the step cycle during treadmill walking. Twenty minutes of 1 Hz rTMS at 115% resting motor threshold (MTr) significantly decreased (P < 0.05) the magnitude of the later component of the reflex at a latency of ∼100 ms up to 25 min after the rTMS. Control experiments in which stretch reflexes were elicited during sitting showed no effect on the spinally mediated short and medium latency stretch reflexes (SLR and MLR) while the long latency stretch reflex (LLR) and the motor-evoked potential (MEP) showed a significant decrease 10 min after 115% MTr rTMS. This study demonstrates that 1 Hz rTMS applied to the leg area of the motor cortex can suppress the long latency TA stretch reflex during sitting and in the stance phase of walking. These results are in line with the hypothesis that the later component of the TA stretch reflex in the stance phase of walking is mediated by a transcortical pathway. An alternative explanation for the observed results is that the reflex is mediated by subcortical structures that are affected by the rTMS. This study also shows that rTMS may be used to study the neural control of walking. PMID:19237419

  9. Repetitive transcranial magnetic stimulation versus botulinum toxin injection in chronic migraine prophylaxis: a pilot randomized trial

    PubMed Central

    Shehata, Hatem S; Esmail, Eman H; Abdelalim, Ahmad; El-Jaafary, Shaimaa; Elmazny, Alaa; Sabbah, Asmaa; Shalaby, Nevin M

    2016-01-01

    Background Chronic migraine is a prevalent disabling disease, with major health-related burden and poor quality of life. Long-term use of preventive medications carries risk of side effects. Objectives The aim of this study was to compare repetitive transcranial magnetic stimulation (rTMS) to botulinum toxin-A (BTX-A) injection as preventive therapies for chronic migraine. Methods A pilot, randomized study was conducted on a small-scale sample of 29 Egyptian patients with chronic migraine, recruited from Kasr Al-Aini teaching hospital outpatient clinic and diagnosed according to ICHD-III (beta version). Patients were randomly assigned into two groups; 15 patients received BTX-A injection following the Phase III Research Evaluating Migraine Prophylaxis Therapy injection paradigm and 14 patients were subjected to 12 rTMS sessions delivered at high frequency (10 Hz) over the left motor cortex (MC, M1). All the patients were requested to have their 1-month headache calendar, and they were subjected to a baseline 25-item (beta version) Henry Ford Hospital Headache Disability Inventory (HDI), Headache Impact Test (HIT-6), and visual analogue scale assessment of headache intensity. The primary efficacy measures were headache frequency and severity; secondary measures were 25-item HDI, HIT-6, and number of acute medications. Follow-up visits were scheduled at weeks 4, 6, 8, 10, and 12 after baseline visit. Results A reduction in all outcome measures was achieved in both the groups. However, this improvement was more sustained in the BTX-A group, and both the therapies were well tolerated. Conclusion BTX-A injection and rTMS have favorable efficacy and safety profiles in chronic migraineurs. rTMS is of comparable efficacy to BTX-A injection in chronic migraine therapy, but with less sustained effect. PMID:27785091

  10. Repetitive transcranial magnetic stimulation decreases the number of seizures in patients with focal neocortical epilepsy.

    PubMed

    Santiago-Rodríguez, Efraín; Cárdenas-Morales, Lizbeth; Harmony, Thalía; Fernández-Bouzas, Antonio; Porras-Kattz, Eneida; Hernández, Adriana

    2008-12-01

    To evaluate the number of seizures and interictal epileptiform discharges (IEDs) in patients with focal neocortical epilepsy before, during and after rTMS. Twelve patients (seven men and five women, mean age 29.3+/-15.8 years) were studied. An open-label study with baseline (4 weeks), intervention (2 weeks) and follow-up (8 weeks) periods was carried out. Repetitive transcranial magnetic stimulation (rTMS) with 900 pulses, intensity of 120% motor resting threshold and 0.5Hz frequency was used. A 120 channel EEG was recorded; an electrical source analysis of IEDs with Variable Resolution Electromagnetic Tomography (VARETA) was performed. The number of seizures per week and IEDs per minute were measured and compared in the three periods. During the basal period the mean seizure frequency was 2.25 per week; in the intervention period it decreased to 0.66 per week (F=2.825; p=0.0036) which corresponds to a 71% reduction. In the follow-up period the mean frequency was 1.14 seizures per week, that is, a 50% reduction in the number of seizures. In the visual EEG analysis, the baseline IED frequency was 11.9+/-8.3events/min; it decreased to 9.3+/-7.9 during 2 weeks of rTMS with a further reduction to 8.2+/-6.6 in the follow-up period. These differences however were not significant (p=0.190). We conclude that 2 weeks of rTMS at 0.5Hz with a figure-of-eight coil placed over the epileptic focus, determined with VARETA, decreases the number of seizures in patients with focal epilepsy, without reduction in IEDs.

  11. Gradual enlargement of human withdrawal reflex receptive fields following repetitive painful stimulation.

    PubMed

    Andersen, Ole K; Spaich, Erika G; Madeleine, Pascal; Arendt-Nielsen, Lars

    2005-05-03

    Dynamic changes in the topography of the human withdrawal reflex receptive fields (RRF) were assessed by repetitive painful stimuli in 15 healthy subjects. A train of five electrical stimuli was delivered at a frequency of 3 Hz (total train duration 1.33 s). The train was delivered in random order to 10 electrode sites on the sole of the foot. Reflexes were recorded from tibialis anterior, soleus, vastus lateralis, biceps femoris, and iliopsoas (IL). The RRF changes during the stimulus train were assessed during standing with even support on both legs and while seated. The degree of temporal summation was depending on stimulation site. At the most sensitive part of the RRF, a statistically significant increase in reflex size was seen after two stimuli while four stimuli were needed to observe reflex facilitation at less sensitive electrode sites. Hence, the region from which reflexes could be evoked using the same stimulus intensity became larger through the train, that is, the RRF was gradually expanding. Reflexes evoked by stimuli four and five were of the same size. No reflex facilitation was seen at other stimulus sites outside the RRF. In all muscles except in IL, the largest reflexes were evoked when the subjects were standing. In the ankle joint, the main withdrawal pattern consisted of plantar flexion and inversion when the subjects were standing while dorsi-flexion was prevalent in the sitting position. Up to 35 degrees of knee and hip flexion were evoked often leading to a lift of the foot from the floor during standing. In conclusion, a gradual expansion of the RRF was seen in all muscles during the stimulus train. Furthermore, the motor programme task controls the reflex sensitivity within the reflex receptive field and, hence, the sensitivity of the temporal summation mechanism.

  12. Repetitive transcranial magnetic stimulation for treatment of major depressive disorder with comorbid generalized anxiety disorder.

    PubMed

    White, Daniela; Tavakoli, Sason

    2015-08-01

    Repetitive transcranial magnetic stimulation (rTMS) has shown promising results in treating individuals with behavioral disorders such as major depressive disorder (MDD), posttraumatic stress disorder, obsessive-compulsive disorder, and social anxiety disorder. A number of applications of rTMS to different regions of the left and right prefrontal cortex have been used to treat these disorders, but no study of treatment for MDD with generalized anxiety disorder (GAD) has been conducted with application of rTMS to both the left and right prefrontal cortex. We hypothesized that applying low-frequency rTMS to the right dorsolateral prefrontal cortex (DLPFC) before applying it to the left DLPFC for the treatment of depression would be anxiolytic in patients with MDD with GAD. Thirteen adult patients with comorbid MDD and GAD received treatment with rTMS in an outpatient setting. The number of treatments ranged from 24 to 36 over 5 to 6 weeks. Response was defined as a ≥ 50% reduction in symptoms from baseline, and remission was defined as a score of < 5 for anxiety symptoms on the 7-item Generalized Anxiety Disorder (GAD-7) scale and < 8 for depressive symptoms on the 21-item Hamilton Rating Scale for Depression (HAM-D-21). At the end of the treatment period, for the GAD-7 scale, 11 out of 13 (84.6%) patients' anxiety symptoms were in remission, achieving a score of < 5 on the GAD-7, and 10 out of 13 patients (76.9%) achieved a HAM-D-21 score of < 8 for depressive symptoms. In this small pilot study of 13 patients with comorbid MDD and GAD, significant improvement in anxiety symptoms along with depressive symptoms was achieved in a majority of patients after bilateral rTMS application.

  13. Therapeutic effects of repetitive transcranial magnetic stimulation in an animal model of Parkinson's disease.

    PubMed

    Lee, Ji Yong; Kim, Sung Hoon; Ko, Ah-Ra; Lee, Jin Suk; Yu, Ji Hea; Seo, Jung Hwa; Cho, Byung Pil; Cho, Sung-Rae

    2013-11-06

    Repetitive transcranial magnetic stimulation (rTMS) is used to treat neurological diseases such as stroke and Parkinson's disease (PD). Although rTMS has been used clinically, its underlying therapeutic mechanism remains unclear. The objective of the present study was to clarify the neuroprotective effect and therapeutic mechanism of rTMS in an animal model of PD. Adult Sprague-Dawley rats were unilaterally injected with 6-hydroxydopamine (6-OHDA) into the right striatum. Rats with PD were then treated with rTMS (circular coil, 10 Hz, 20 min/day) daily for 4 weeks. Behavioral assessments such as amphetamine-induced rotational test and treadmill locomotion test were performed, and the dopaminergic (DA) neurons of substantia nigra pas compacta (SNc) and striatum were histologically examined. Expression of neurotrophic/growth factors was also investigated by multiplex ELISA, western blotting analysis and immunohistochemistry 4 weeks after rTMS application. Among the results, the number of amphetamine-induced rotations was significantly lower in the rTMS group than in the control group at 4 weeks post-treatment. Treadmill locomotion was also significantly improved in the rTMS-treated rats. Tyrosine hydroxylase-positive DA neurons and DA fibers in rTMS group rats were greater than those in untreated group in both ipsilateral SNc and striatum, respectively. The expression levels of brain-derived neurotrophic factor, glial cell line-derived neurotrophic factor, platelet-derived growth factor, and vascular endothelial growth factor were elevated in both the 6-OHDA-injected hemisphere and the SNc of the rTMS-treated rats. In conclusion, rTMS treatment improved motor functions and survival of DA neurons, suggesting that the neuroprotective effect of rTMS treatment might be induced by upregulation of neurotrophic/growth factors in the PD animal model.

  14. Knowledge of and Attitude Toward Repetitive Transcranial Magnetic Stimulation Among Psychiatrists in Saudi Arabia

    PubMed Central

    AlHadi, Ahmad N.; AlShiban, Abdulrahman M.; Alomar, Majed A.; Aljadoa, Othman F.; AlSayegh, Ahmed M.; Jameel, Mohammed A.

    2017-01-01

    Objectives The aims of this study were to assess psychiatrists' knowledge of and attitudes toward repetitive transcranial magnetic stimulation (rTMS) in Saudi Arabia and to determine the contributing factors. Methods A quantitative observational cross-sectional study was conducted using an online survey. The sample consisted of 96 psychiatrists in Saudi Arabia. A new valid and reliable questionnaire was developed. Results A total of 96 psychiatrists enrolled in the study, 81% of whom were men. Half of the participants were consultants. The sample mainly consisted of general psychiatrists (65%). The mean age of the participants was 37 years. The results showed that 80% of the psychiatrists had a sufficient level of knowledge about rTMS. Consultants had greater knowledge than residents. Training abroad was not significantly associated with the level of knowledge or the type of attitude. Most psychiatrists (79%) had a positive attitude toward rTMS. Only 53% of the psychiatrists said they would agree to receive rTMS if they experienced a psychotic depressive condition. A minority of psychiatrists (7%) said they would not refer their patients for rTMS. Conclusions Most of the psychiatrists surveyed had good knowledge of and a positive attitude toward rTMS. Those who had a high level of training and experience showed higher levels of knowledge. Articles were reported to be a better source for improving physician knowledge than textbooks. Having a family member or relative who was treated with rTMS positively affected psychiatrists' attitudes toward rTMS. PMID:27564426

  15. Efficacy of synchronous verbal training during repetitive transcranial magnetic stimulation in patients with chronic aphasia.

    PubMed

    Wang, Chih-Pin; Hsieh, Chin-Yi; Tsai, Po-Yi; Wang, Chia-To; Lin, Fu-Gong; Chan, Rai-Chi

    2014-12-01

    Although multiple studies have suggested that repetitive transcranial magnetic stimulation (rTMS) may facilitate recovery after stroke, the efficacy of synchronous speech therapy integrated with an rTMS protocol has yet to be determined. We investigated language responses to this strategy and determined the longevity of the resulting therapeutic outcomes. Forty-five patients with stroke who presented with nonfluent aphasia were randomly assigned to the TMSsyn group and underwent synchronous picture-naming training together with contralesional 1 Hz-rTMS for 10 daily sessions. The TMSsub group underwent subsequent picture-naming activity after the primed 1 Hz-rTMS, and the TMSsham group received concurrent naming task along with the sham 1 Hz-rTMS. The Concise Chinese Aphasia test and the picture-naming test were performed before, immediately, and after 3 months of the intervention. TMSsyn showed significantly superior results in Concise Chinese Aphasia test score (P<0.001), expression and description subtests (P<0.001), and action (P=0.02) and object naming activity (P=0.008); the superior results lasted for 3 months (P=0.005), in comparison with the TMSsub and TMSsham groups. We established a real-time model that involved implementing verbal tasks together with the rTMS protocol. Our results confirmed that the strategy yielded favorable outcomes that were of considerable longevity. The results also indicated that the rTMS protocol and language training can be combined to achieve outcomes superior to those obtained when used separately. http://www.clinicaltrials.gov. Unique identifier: NCT02120508. © 2014 American Heart Association, Inc.

  16. Effects of repetitive transcranial magnetic stimulation on the somatosensory cortex during prism adaptation.

    PubMed

    Yoon, Hee-Chul; Lee, Kyung-Hyun; Huh, Dong-Chan; Lee, Ji-Hang; Lee, Dong-Hyun

    2014-04-01

    Although the behavioral characteristics and the neural correlates of prism adaptation processes have been studied extensively, the underlying mechanism is yet to be investigated. Recently, somatosensory suppression was heralded as a mechanism for the sensory re-alignment process accompanying the adaptation. Somatosensory suppression should facilitate the re-alignment process in the proprioceptive system. The shift in the proprioceptive system takes place mostly during a concurrent visual feedback (CVF) condition; during a terminal visual feedback (TVF) condition, the visual system experiences significant adaptation (visual shift), so somatosensory suppression should have minimal functional consequences under TVF. To test this hypothesis, a repetitive transcranial magnetic stimulation (rTMS) was applied to the primary somatosensory cortex as an artificial somatosensory suppression right after the reaching initiation in CVF and TVF conditions, and changes in adaptation were observed. Because somatosensory suppression is already in effect during CVF, rTMS would cause no significant changes. During TVF with rTMS, however, significantly different patterns of adaptation could be expected when compared to a sham rTMS condition. Young adults (N = 12) participated in 4 sessions (CVF/ TVF, real/sham rTMS); visual proprioceptive, and total shifts were measured. Movement time and curvature of the reaching movement were measured during the adaptation phase. Results showed that while the total shift was unchanged, the proprioceptive shift increased and the visual shift decreased in the TVF condition when rTMS was delivered. However, the total, proprioceptive, and visual shifts were not influenced by rTMS in the CVF condition. Suppression of proprioception induced by the rTMS could be one of the requisites for successful proprioceptive shift during prism adaptation.

  17. Cognitive safety of dorsomedial prefrontal repetitive transcranial magnetic stimulation in major depression.

    PubMed

    Schulze, Laura; Wheeler, Sarah; McAndrews, Mary Pat; Solomon, Chloe J E; Giacobbe, Peter; Downar, Jonathan

    2016-07-01

    The most widely used target for repetitive transcranial magnetic stimulation (rTMS) in treatment-resistant depression (TRD) is the dorsolateral prefrontal cortex (DLPFC). Despite convergent evidence that the dorsomedial prefrontal cortex (DMPFC) may be a promising alternative target for rTMS in TRD, its cognitive safety profile has not previously been assessed. Here, we applied 20 sessions of rTMS to the DMPFC in 21 TRD patients. Before and after treatment, a battery of neuropsychological tasks was administered to evaluate changes in cognition across three general cognitive domains: learning and memory, attention and processing speed, and cognitive flexibility. Subjects also completed the 17-item Hamilton Rating Scale for Depression (HamD17) prior to and following treatment to measure changes in severity of depressive symptoms, and to assess the relationship between mood and cognitive performance over the course of treatment. No serious adverse effects or significant deterioration in cognitive performance were observed. Overall, subjects improved significantly on Stroop Inhibition/Switching and on Trails B, and this improvement was independent of the degree of improvement in depression symptoms. No domains or items significantly predicted clinical outcome, with the exception of baseline performance on Visual Elevator Accuracy. Clinical improvement correlated to improved performance in the overall domain of attention and processing speed, although this effect was not evident following covariate adjustment. DMPFC-rTMS did not produce any detectable cognitive adverse effects during treatment of TRD. Performance did not deteriorate significantly on any measures. Taken together, the present findings support the tolerability and cognitive safety of DMPFC-rTMS in refractory depression.

  18. [Hospital production cost of repetitive transcranial magnetic stimulation (rTMS) in the treatment of depression].

    PubMed

    Etcheverrigaray, F; Bulteau, S; Machon, L O; Riche, V P; Mauduit, N; Tricot, R; Sellal, O; Sauvaget, A

    2015-08-01

    Repetitive transcranial magnetic stimulation (rTMS) is an effective and well-tolerated treatment in resistant depression with mild to moderate intensity. This indication has not yet been approved in France. The cost and medico-economic value of rTMS in psychiatry remains unknown. The aim of this preliminary study was to assess rTMS cost production analysis as an in-hospital treatment for depression. The methodology, derived from analytical accounts, was validated by a multidisciplinary task force (clinicians, public health doctors, pharmacists, administrative officials and health economist). It was pragmatic, based on official and institutional documentary sources and from field practice. It included equipment, staff, and structure costs, to get an estimate as close to reality as possible. First, we estimated the production cost of rTMS session, based on our annual activity. We then estimated the cost of a cure, which includes 15 sessions. A sensitivity analysis was also performed. The hospital production cost of a cure for treating depression was estimated at € 1932.94 (€ 503.55 for equipment, € 1082.75 for the staff, and € 346.65 for structural expenses). This cost-estimate has resulted from an innovative, pragmatic, and cooperative approach. It is slightly higher but more comprehensive than the costs estimated by the few international studies. However, it is limited due to structure-specific problems and activity. This work could be repeated in other circumstances in order to obtain a more general estimate, potentially helpful for determining an official price for the French health care system. Moreover, budgetary constraints and public health choices should be taken into consideration. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  19. Repetitive Nerve Stimulation in MuSK-Antibody-Positive Myasthenia Gravis.

    PubMed

    Kim, Seung Woo; Sunwoo, Mun Kyung; Kim, Seung Min; Shin, Ha Young; Sunwoo, Il Nam

    2017-07-01

    Responses to repetitive nerve stimulation (RNS) in patients with muscle-specific tyrosine kinase (MuSK) antibody (Ab)-positive myasthenia gravis (MG) vary depending on the muscles tested. We analyzed the RNS responses of limb and facial muscles in MuSK-Ab-positive and acetylcholine receptor (AChR)-Ab-negative MG (MuSK MG) and MuSK-Ab-negative and AChR-Ab-negative [double-seronegative (DSN)] MG patients. We retrospectively compared RNS responses between 45 MuSK MG and 29 DSN MG. RNS was applied to the abductor digiti minimi, flexor carpi ulnaris, trapezius, orbicularis oculi, and nasalis muscles. Abnormal RNS responses in limb muscles were observed in 22.2 and 58.6% of MuSK MG and DSN MG patients, respectively, with abnormal facial responses observed in 77.8 and 65.5%, and abnormal responses observed in any of the five muscles in 86.7 and 72.4%. Abnormal RNS responses in the abductor digiti minimi or flexor carpi ulnaris were less frequent in MuSK MG (8.9 and 15.6%, respectively) than in DSN MG (37.9 and 55.2%), whereas the findings for other muscles were not significantly different between the groups. Abnormal facial responses but normal limb responses were independently associated with MuSK MG (odds ratio=5.224, 95% confidence interval=1.300-20.990). Abnormal RNS responses primarily in facial muscles without involvement of limb muscles were more pronounced in MuSK MG than in DSN MG. RNS of both facial and limb muscles in AChR-Ab-negative MG can increase the test sensitivity and aid in early suspicion of MuSK MG.

  20. Evidence-based guidelines on the therapeutic use of repetitive transcranial magnetic stimulation (rTMS).

    PubMed

    Lefaucheur, Jean-Pascal; André-Obadia, Nathalie; Antal, Andrea; Ayache, Samar S; Baeken, Chris; Benninger, David H; Cantello, Roberto M; Cincotta, Massimo; de Carvalho, Mamede; De Ridder, Dirk; Devanne, Hervé; Di Lazzaro, Vincenzo; Filipović, Saša R; Hummel, Friedhelm C; Jääskeläinen, Satu K; Kimiskidis, Vasilios K; Koch, Giacomo; Langguth, Berthold; Nyffeler, Thomas; Oliviero, Antonio; Padberg, Frank; Poulet, Emmanuel; Rossi, Simone; Rossini, Paolo Maria; Rothwell, John C; Schönfeldt-Lecuona, Carlos; Siebner, Hartwig R; Slotema, Christina W; Stagg, Charlotte J; Valls-Sole, Josep; Ziemann, Ulf; Paulus, Walter; Garcia-Larrea, Luis

    2014-11-01

    A group of European experts was commissioned to establish guidelines on the therapeutic use of repetitive transcranial magnetic stimulation (rTMS) from evidence published up until March 2014, regarding pain, movement disorders, stroke, amyotrophic lateral sclerosis, multiple sclerosis, epilepsy, consciousness disorders, tinnitus, depression, anxiety disorders, obsessive-compulsive disorder, schizophrenia, craving/addiction, and conversion. Despite unavoidable inhomogeneities, there is a sufficient body of evidence to accept with level A (definite efficacy) the analgesic effect of high-frequency (HF) rTMS of the primary motor cortex (M1) contralateral to the pain and the antidepressant effect of HF-rTMS of the left dorsolateral prefrontal cortex (DLPFC). A Level B recommendation (probable efficacy) is proposed for the antidepressant effect of low-frequency (LF) rTMS of the right DLPFC, HF-rTMS of the left DLPFC for the negative symptoms of schizophrenia, and LF-rTMS of contralesional M1 in chronic motor stroke. The effects of rTMS in a number of indications reach level C (possible efficacy), including LF-rTMS of the left temporoparietal cortex in tinnitus and auditory hallucinations. It remains to determine how to optimize rTMS protocols and techniques to give them relevance in routine clinical practice. In addition, professionals carrying out rTMS protocols should undergo rigorous training to ensure the quality of the technical realization, guarantee the proper care of patients, and maximize the chances of success. Under these conditions, the therapeutic use of rTMS should be able to develop in the coming years.

  1. Topiramate and cortical excitability in humans: a study with repetitive transcranial magnetic stimulation.

    PubMed

    Inghilleri, M; Gilio, F; Conte, A; Frasca, V; Marini Bettolo, C; Iacovelli, E; Gregori, B; Prencipe, M; Berardelli, A

    2006-10-01

    Repetitive transcranial magnetic stimulation (rTMS) delivered at 5 Hz frequency and suprathreshold intensity progressively increases the size of muscle evoked potentials (MEPs) and the duration of the cortical silent period (CSP) in normal subjects. The aim of this study was to evaluate the effects of topiramate (TPM) at different doses on cortical excitability variables tested with rTMS. We tested the facilitation of the MEP size and CSP duration evoked by focal rTMS in eight patients before and after treatment with TPM at different doses for chronic neuropathic pain. In each patient, rTMS (5 Hz frequency-120% resting motor threshold) was applied at baseline and during the TPM induction phase (drug intake schedule: week I 25 mg/day, week II 50 mg/day, week III 75 mg/day, week IV 100 mg/day) and total TPM plasma concentrations were measured. The effects on the MEP size of 5 Hz-rTMS delivered over repeated sessions were tested in eight control subjects. TPM had no effect on the resting motor threshold. Antiepileptic treatment at increasing doses abolished the normal rTMS-induced MEP facilitation. ANOVA showed that this was a dose-related effect. Accordingly, in patients receiving TPM at higher doses (75 and 100 mg) rTMS failed to elicit the MEP facilitation. TPM left the progressive lengthening of the CSP during the rTMS train unchanged. In control subjects, rTMS applied over repeated sessions elicited a constant increase in MEP size. Our results suggest that TPM modulates the excitatory intracortical interneurons probably by altering rTMS-induced synaptic potentiation. These drug-induced effects are related to TPM doses and plasma concentrations. In conclusion, rTMS may be useful for quantifying the effectiveness of antiepileptic drugs and for assessing individual responses to different drugs but acting through similar mechanisms, thus combining functional neurophysiological information and laboratory data.

  2. Cortical excitability changes after high-frequency repetitive transcranial magnetic stimulation for central poststroke pain.

    PubMed

    Hosomi, Koichi; Kishima, Haruhiko; Oshino, Satoru; Hirata, Masayuki; Tani, Naoki; Maruo, Tomoyuki; Yorifuji, Shiro; Yoshimine, Toshiki; Saitoh, Youichi

    2013-08-01

    Central poststroke pain (CPSP) is one of the most refractory chronic pain syndromes. Repetitive transcranial magnetic stimulation (rTMS) of the primary motor cortex has been demonstrated to provide moderate pain relief for CPSP. However, the mechanism underlying the pain relief remains unclear. The objective of this study was to assess changes in cortical excitability in patients with intractable CPSP before and after rTMS of the primary motor cortex. Subjects were 21 patients with CPSP of the hand who underwent rTMS. The resting motor threshold, the amplitude of the motor evoked potential, duration of the cortical silent period, short interval intracortical inhibition, and intracortical facilitation were measured as parameters of cortical excitability before and after navigation-guided 5 Hz rTMS of the primary motor cortex corresponding to the painful hand. Pain reduction from rTMS was assessed with a visual analog scale. The same parameters were measured in both hemispheres of 8 healthy controls. Eight of 21 patients experienced ≥ 30% pain reduction after rTMS (responders). The resting motor threshold in the patients was higher than those in the controls at baseline (P=.035). Intracortical facilitation in the responders was lower than in the controls and the nonresponders at baseline (P=.035 and P=.019), and significantly increased after rTMS (P=.039). There were no significant differences or changes in the other parameters. Our findings suggest that restoration of abnormal cortical excitability might be one of the mechanisms underlying pain relief as a result of rTMS in CPSP.

  3. Effect of low-frequency repetitive transcranial magnetic stimulation combined with physical therapy on L-dopa-induced painful off-period dystonia in Parkinson's disease.

    PubMed

    Kodama, Mitsuhiko; Kasahara, Takashi; Hyodo, Masaki; Aono, Koji; Sugaya, Mutsumi; Koyama, Yuji; Hanayama, Kozo; Masakado, Yoshihisa

    2011-02-01

    Previous research has shown that low-frequency repetitive transcranial magnetic stimulation over the primary motor area and supplementary motor area can reduce L-dopa-induced dyskinesias in Parkinson's disease; however, it involved only patients with peak-dose or diphasic dyskinesia. We report a case of a patient with severely painful off-period dystonia in the unilateral lower limb who underwent 0.9-Hz subthreshold repetitive transcranial magnetic stimulation over contralateral primary motor area and supplementary motor area. Repetitive transcranial magnetic stimulation over the primary motor area significantly reduced the painful dystonia and walking disturbances but repetitive transcranial magnetic stimulation over the supplementary motor area did not. The cortical silent period also prolonged after repetitive transcranial magnetic stimulation over the primary motor area. At 5 mos of approximately once a week repetitive transcranial magnetic stimulation over the primary motor area, the Unified Parkinson's Disease Rating Scale motor score also improved. This report shows that repetitive transcranial magnetic stimulation over the inhibitory primary motor area can be useful for rehabilitating patients with Parkinson's disease with off-period dystonia and suggests that this treatment should be further verified in such patients.

  4. Functional MRI-navigated repetitive transcranial magnetic stimulation over supplementary motor area in chronic tic disorders.

    PubMed

    Wu, Steve W; Maloney, Thomas; Gilbert, Donald L; Dixon, Stephan G; Horn, Paul S; Huddleston, David A; Eaton, Kenneth; Vannest, Jennifer

    2014-01-01

    Open label studies have shown repetitive transcranial magnetic stimulation to be effective in reducing tics. To determine whether 8 sessions of continuous theta burst stimulation (cTBS) over supplementary motor area (SMA) given over 2 days may reduce tics and motor cortical network activity in Tourette syndrome/chronic tic disorders. This was a randomized (1:1), double-blind, sham-controlled trial of functional MRI (fMRI)-navigated, 30 Hz cTBS at 90% of resting motor threshold (RMT) over SMA in 12 patients ages 10-22 years. Comorbid ADHD (n = 8), OCD (n = 8), and stable concurrent medications (n = 9) were permitted. Neuro-navigation utilized each individual's event-related fMRI signal. Primary clinical and cortical outcomes were: 1) Yale Global Tic Severity Scale (YGTSS) at one week; 2) fMRI event-related signal in SMA and primary motor cortex (M1) during a finger-tapping motor task. Baseline characteristics were not statistically different between groups (age, current tic/OCD/ADHD severities, tic-years, number of prior medication trials, RMT). Mean YGTSS scores decreased in both active (27.5 ± 7.4 to 23.2 ± 9.8) and sham (26.8 ± 4.8 to 21.7 ± 7.7) groups. However, no significant difference in video-based tic severity rating was detected between the two groups. Two-day post-treatment fMRI activation during finger tapping decreased significantly in active vs. sham groups for SMA (P = 0.02), left M1 (P = 0.0004), and right M1 (P < 0.0001). No serious adverse events occurred. Active, fMRI-navigated cTBS administered in 8 sessions over 2 days to the SMA induced significant inhibition in the motor network (SMA, bilateral M1). However, both groups on average experienced tic reduction at 7 days. Larger sample size and protocol modifications may be needed to produce clinically significant tic reduction beyond placebo effect. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. The effect of repetitive transcranial magnetic stimulation on monoamine outflow in the nucleus accumbens shell in freely moving rats.

    PubMed

    Löffler, Susanne; Gasca, Fernando; Richter, Lars; Leipscher, Ulrike; Trillenberg, Peter; Moser, Andreas

    2012-10-01

    Evidence exists that modulation of neuronal activity in nucleus accumbens shell region may re-establish normal function in various neuropsychiatric conditions such as drug-withdrawal, obsessive-compulsive disorder, depression and chronic pain. Here, we study the effects of acute repetitive transcranial magnetic stimulation on monoamine outflow in the nucleus accumbens shell in awake and freely moving rats using in vivo microdialysis. To scale the biochemical results to the induced electric field in the rat brain, we obtained a realistic simulation of the stimulation scenario using a finite element model. Applying 20 Hz repetitive transcranial magnetic stimulation in 6 trains of 50 stimuli with 280 μs pulse width at a magnetic field strength of 130% of the individual motor threshold, dopamine as well as serotonin outflow in the nucleus accumbens shell significantly increased compared to sham stimulation. Since the electric field decays rapidly with depth in the rat brain, we can conclude that the modulation in neurotransmitter outflow from the nucleus accumbens shell is presumably a remote effect of cortical stimulation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Improved Acuity and Dexterity but Unchanged Touch and Pain Thresholds following Repetitive Sensory Stimulation of the Fingers

    PubMed Central

    Kowalewski, Rebecca; Kattenstroth, Jan-Christoph; Kalisch, Tobias; Dinse, Hubert R.

    2012-01-01

    Neuroplasticity underlies the brain's ability to alter perception and behavior through training, practice, or simply exposure to sensory stimulation. Improvement of tactile discrimination has been repeatedly demonstrated after repetitive sensory stimulation (rSS) of the fingers; however, it remains unknown if such protocols also affect hand dexterity or pain thresholds. We therefore stimulated the thumb and index finger of young adults to investigate, besides testing tactile discrimination, the impact of rSS on dexterity, pain, and touch thresholds. We observed an improvement in the pegboard task where subjects used the thumb and index finger only. Accordingly, stimulating 2 fingers simultaneously potentiates the efficacy of rSS. In fact, we observed a higher gain of discrimination performance as compared to a single-finger rSS. In contrast, pain and touch thresholds remained unaffected. Our data suggest that selecting particular fingers modulates the efficacy of rSS, thereby affecting processes controlling sensorimotor integration. PMID:22315693

  7. A Neuronal Network Model for Simulating the Effects of Repetitive Transcranial Magnetic Stimulation on Local Field Potential Power Spectra

    PubMed Central

    Bey, Alina; Leue, Stefan; Wienbruch, Christian

    2012-01-01

    Repetitive transcranial magnetic stimulation (rTMS) holds promise as a non-invasive therapy for the treatment of neurological disorders such as depression, schizophrenia, tinnitus, and epilepsy. Complex interdependencies between stimulus duration, frequency and intensity obscure the exact effects of rTMS stimulation on neural activity in the cortex, making evaluation of and comparison between rTMS studies difficult. To explain the influence of rTMS on neural activity (e.g. in the motor cortex), we use a neuronal network model. The results demonstrate that the model adequately explains experimentally observed short term effects of rTMS on the band power in common frequency bands used in electroencephalography (EEG). We show that the equivalent local field potential (eLFP) band power depends on stimulation intensity rather than on stimulation frequency. Additionally, our model resolves contradictions in experiments. PMID:23145082

  8. A neuronal network model for simulating the effects of repetitive transcranial magnetic stimulation on local field potential power spectra.

    PubMed

    Bey, Alina; Leue, Stefan; Wienbruch, Christian

    2012-01-01

    Repetitive transcranial magnetic stimulation (rTMS) holds promise as a non-invasive therapy for the treatment of neurological disorders such as depression, schizophrenia, tinnitus, and epilepsy. Complex interdependencies between stimulus duration, frequency and intensity obscure the exact effects of rTMS stimulation on neural activity in the cortex, making evaluation of and comparison between rTMS studies difficult. To explain the influence of rTMS on neural activity (e.g. in the motor cortex), we use a neuronal network model. The results demonstrate that the model adequately explains experimentally observed short term effects of rTMS on the band power in common frequency bands used in electroencephalography (EEG). We show that the equivalent local field potential (eLFP) band power depends on stimulation intensity rather than on stimulation frequency. Additionally, our model resolves contradictions in experiments.

  9. High repetition rate passively Q-switched fiber and microchip lasers for optical resolution photoacoustic imaging

    NASA Astrophysics Data System (ADS)

    Shi, Wei; Utkin, Ilya; Ranasinghesagara, Janaka; Pan, Lei; Godwal, Yogesh; Kerr, Shaun; Zemp, Roger J.; Fedosejevs, Robert

    2010-02-01

    Optical-resolution photoacoustic microscopy is a novel imaging technology for visualizing optically-absorbing superficial structures in vivo with lateral spatial resolution determined by optical focusing rather than acoustic detection. Since scanning of the illumination spot is required, the imaging speed is limited by the scanning speed and the laser pulse repetition rate. Unfortunately, lasers with high-repetition rate and suitable pulse durations and energies are difficult to find. We are developing compact laser sources for this application. Passively Q-switched fiber and microchip lasers with pulse repetition rates up to 300 kHz are demonstrated. Using a diode-pumped microchip laser fiber-coupled to a large mode-area Yb-doped fiber amplifier we obtained 60μJ 1-ns pulses at the frequency-doubled 532-nm wavelength. The pulse-repetition rate was determined by the power of the microchip laser pump source at 808nm and may exceed 10 kHz. Additionally, a passively Q-switched fiber laser utilizing a Yb-doped double-cladding fiber and an external saturable absorber has shown to produce 250ns pulses at repetition rates of 100-300 KHz. A photoacoustic probe enabling flexible scanning of the focused output of these lasers consisted of a 45-degree glass prism in an optical index-matching fluid. Photoacoustic signals exiting the sample are deflected by the prism to an ultrasound transducer. Phantom studies with a 7.5-micron carbon fiber demonstrate the ability to image with optical rather than acoustic resolution. We believe that the high pulse-repetition rates and the potentially compact and fiber-coupled nature of these lasers will prove important for clinical imaging applications where realtime imaging performance is essential.

  10. Flashbulb memories and other repetitive images: a psychiatric perspective.

    PubMed

    Sierra, M; Berrios, G E

    1999-01-01

    The term "flashbulb memory" was used by Brown and Kulik in 1977 to refer to the vivid recollections that humans may have of events considered to be of particular significance to the individual or group. These memories are described as having a photographic quality and as being accompanied by a detail-perfect apparel of contextual information (weather, background music, clothes worn, etc.) pertaining to the time and place where the event was first known. They may even evoke emotions similar to the ones felt upon hearing the news. It has been suggested that flashbulb memories are formed by the activity of an ancient brain mechanism evolved to capture emotional and cognitive information relevant to the survival of the individual or group. Some of the original assumptions made by Brown and Kulik have since been challenged, but the phenomenon in question remains an important area of research. However, the latter is often marred by the fact that flashbulb memories are studied as if they were unique psychological events without parallel in clinical practice. Psychiatrists, however, should consider flashbulb memories as being members of a broad family of experiences that include drug flashbacks, palinopsia, palinacusis, posttraumatic memories, and the vivid and haunting memories experienced by subjects with some forms of mental disorder (e.g., phobias, panic attacks, obsessional disorder, phantom-limb phenomena, and depressive melancholia). All of these experiences share clinical features such as paroxysmal repetition, sensory vividness, a capacity to trigger emotions, dysphoria, and a tendency for the rememberer to shift from the role of actor to that of observer and for the reminiscence to become organized in a stereotyped narrative. Some of these clinical phenomena are discussed, and the suggestion is made that seeking phenomenological and neurobiological common denominators to all of these experiences may be a superior research strategy versus studying flashbulb

  11. Kinetic changes in tetanic Ca2+ transients in enzymatically dissociated muscle fibres under repetitive stimulation

    PubMed Central

    Calderón, Juan C; Bolaños, Pura; Caputo, Carlo

    2011-01-01

    Abstract We used enzymatically dissociated flexor digitorum brevis (FDB) and soleus fibres loaded with the fast Ca2+ dye Magfluo-4 AM, and adhered to Laminin, to test whether repetitive stimulation induces progressive changes in the kinetics of Ca2+ release and reuptake in a fibre-type-dependent fashion. We applied a protocol of tetani of 350 ms, 100 Hz, every 4 s to reach a mean amplitude reduction of 25% of the first peak. Morphology type I (MT-I) and morphology type II (MT-II) fibres underwent a total of 96 and 52.8 tetani (P < 0.01 between groups), respectively. The MT-II fibres (n = 18) showed significant reductions of the amplitude (19%), an increase in rise time (8.5%) and a further reduction of the amplitude/rise time ratio (25.5%) of the first peak of the tetanic transient after 40 tetani, while MT-I fibres (n = 5) did not show any of these changes. However, both fibre types showed significant reductions in the maximum rate of rise of the first peak after 40 tetani. Two subpopulations among the MT-II fibres could be distinguished according to Ca2+ reuptake changes. Fast-fatigable MT-II fibres (fMT-II) showed an increase of 32.2% in the half-width value of the first peak, while for fatigue-resistant MT-II fibres (rMT-II), the increase amounted to 6.9%, both after 40 tetani. Significant and non-significant increases of 36.4% and 11.9% in the first time constant of decay (t1) values were seen after 40 tetani in fMT-II and rMT-II fibres, respectively. MT-I fibres did not show kinetic changes in any of the Ca2+ reuptake variables. All changes were reversed after an average recovery of 7.5 and 15.4 min for MT-I and MT-II fibres, respectively. Further experiments ruled out the possibility that the differences in the kinetic changes of the first peak of the Ca2+ transients between fibres MT-I and MT-II could be related to the inactivation of Ca2+ release mechanism. In conclusion, we established a model of enzymatically dissociated fibres, loaded with Magfluo-4 and

  12. Improvement of higher brain dysfunction after brain injury by repetitive transcranial magnetic stimulation and intensive rehabilitation therapy: case report.

    PubMed

    Hara, Takatoshi; Abo, Masahiro; Sasaki, Nobuyuki; Yamada, Naoki; Niimi, Masachika; Kenmoku, Mari; Kawakami, Kastuya; Saito, Reiko

    2017-09-06

    Repetitive transcranial magnetic stimulation (rTMS) and intensive cognitive rehabilitation (CR) were administered to two patients with cognitive dysfunction following brain injury. The first case was a 67-year-old man who presented with memory dysfunction, attention dysfunction, and decreased insight following diffuse axonal injury. High-frequency rTMS (10 Hz, 2400 pulses/day) targeting the anterior cingulate using a navigation system and CR were administered for 12 days at 1 year from the onset of injury. The patient showed improved neuropsychological performance and activities of daily living. In addition, single photon emission computer tomography with Tc-ECD showed improved perfusion in the anterior cingulate gyrus. The second case was a 68-year-old man who presented with dysfunction of memory, attention, and executive function following a cerebral infarction in the middle cerebral artery region within the right hemisphere. This patient received 12 days (except for Sundays) of low-frequency rTMS (1 Hz, 1200 pulses/day) targeting the left dorsolateral prefrontal cortex and the left posterior parietal cortex and CR. Following this intervention, the patient's neuropsychological performance and activities of daily living improved. Furthermore, single photon emission computer tomography showed changes in perfusion in the rTMS target sites and areas surrounding the targets. We have shown the safety and efficacy of rTMS therapy using a navigation system combined with intensive CR on two patients with cognitive dysfunction following brain injury. In addition, we observed changes in the areas around the rTMS target sites in brain imaging data.

  13. Induction of central nervous system plasticity by repetitive transcranial magnetic stimulation to promote sensorimotor recovery in incomplete spinal cord injury

    PubMed Central

    Ellaway, Peter H.; Vásquez, Natalia; Craggs, Michael

    2014-01-01

    Cortical and spinal cord plasticity may be induced with non-invasive transcranial magnetic stimulation to encourage long term potentiation or depression of neuronal circuits. Such plasticity inducing stimulation provides an attractive approach to promote changes in sensorimotor circuits that have been degraded by spinal cord injury (SCI). If residual corticospinal circuits can be conditioned appropriately there should be the possibility that the changes are accompanied by functional recovery. This article reviews the attempts that have been made to restore sensorimotor function and to obtain functional benefits from the application of repetitive transcranial magnetic stimulation (rTMS) of the cortex following incomplete spinal cord injury. The confounding issues that arise with the application of rTMS, specifically in SCI, are enumerated. Finally, consideration is given to the potential for rTMS to be used in the restoration of bladder and bowel sphincter function and consequent functional recovery of the guarding reflex. PMID:24904326

  14. Effect of high-frequency repetitive transcranial magnetic stimulation on motor cortical excitability and sensory nerve conduction velocity in subacute-stage incomplete spinal cord injury patients.

    PubMed

    Cha, Hyun Gyu; Ji, Sang-Goo; Kim, Myoung-Kwon

    2016-07-01

    [Purpose] The aim of the present study was to determine whether repetitive transcranial magnetic stimulation can improve sensory recovery of the lower extremities in subacute-stage spinal cord injury patients. [Subjects and Methods] This study was conducted on 20 subjects with diagnosed paraplegia due to spinal cord injury. These 20 subjects were allocated to an experimental group of 10 subjects that underwent active repetitive transcranial magnetic stimulation or to a control group of 10 subjects that underwent sham repetitive transcranial magnetic stimulation. The SCI patients in the experimental group underwent active repetitive transcranial magnetic stimulation and conventional rehabilitation therapy, whereas the spinal cord injury patients in the control group underwent sham repetitive transcranial magnetic stimulation and conventional rehabilitation therapy. Participants in both groups received therapy five days per week for six-weeks. Latency, amplitude, and sensory nerve conduction velocity were assessed before and after the six week therapy period. [Results] A significant intergroup difference was observed for posttreatment velocity gains, but no significant intergroup difference was observed for amplitude or latency. [Conclusion] repetitive transcranial magnetic stimulation may be improve sensory recovery of the lower extremities in subacute-stage spinal cord injury patients.

  15. The use of repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) to relieve pain.

    PubMed

    Lefaucheur, Jean-Pascal; Antal, Andrea; Ahdab, Rechdi; Ciampi de Andrade, Daniel; Fregni, Felipe; Khedr, Eman M; Nitsche, Michael; Paulus, Walter

    2008-10-01

    Chronic pain resulting from injury of the peripheral or central nervous system may be associated with a significant dysfunction of extensive neural networks. Noninvasive stimulation techniques, such as repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) may be suitable to treat chronic pain as they can act on these networks by modulating neural activities not only in the stimulated area, but also in remote regions that are interconnected to the site of stimulation. Motor cortex was the first cortical target that was proved to be efficacious in chronic pain treatment. At present, significant analgesic effects were also shown to occur after the stimulation of other cortical targets (including prefrontal and parietal areas) in acute provoked pain, chronic neuropathic pain, fibromyalgia, or visceral pain. Therapeutic applications of rTMS in pain syndromes are limited by the short duration of the induced effects, but prolonged pain relief can be obtained by repeating rTMS sessions every day for several weeks. Recent tDCS studies also showed some effects on various types of chronic pain. We review the evidence to date of these two techniques of noninvasive brain stimulation for the treatment of pain.

  16. Effects of different frequencies of repetitive transcranial magnetic stimulation on the recovery of upper limb motor dysfunction in patients with subacute cerebral infarction.

    PubMed

    Li, Jiang; Meng, Xiang-Min; Li, Ru-Yi; Zhang, Ru; Zhang, Zheng; Du, Yi-Feng

    2016-10-01

    Studies have confirmed that low-frequency repetitive transcranial magnetic stimulation can decrease the activity of cortical neurons, and high-frequency repetitive transcranial magnetic stimulation can increase the excitability of cortical neurons. However, there are few studies concerning the use of different frequencies of repetitive transcranial magnetic stimulation on the recovery of upper-limb motor function after cerebral infarction. We hypothesized that different frequencies of repetitive transcranial magnetic stimulation in patients with cerebral infarction would produce different effects on the recovery of upper-limb motor function. This study enrolled 127 patients with upper-limb dysfunction during the subacute phase of cerebral infarction. These patients were randomly assigned to three groups. The low-frequency group comprised 42 patients who were treated with 1 Hz repetitive transcranial magnetic stimulation on the contralateral hemisphere primary motor cortex (M1). The high-frequency group comprised 43 patients who were treated with 10 Hz repetitive transcranial magnetic stimulation on ipsilateral M1. Finally, the sham group comprised 42 patients who were treated with 10 Hz of false stimulation on ipsilateral M1. A total of 135 seconds of stimulation was applied in the sham group and high-frequency group. At 2 weeks after treatment, cortical latency of motor-evoked potentials and central motor conduction time were significantly lower compared with before treatment. Moreover, motor function scores were significantly improved. The above indices for the low- and high-frequency groups were significantly different compared with the sham group. However, there was no significant difference between the low- and high-frequency groups. The results show that low- and high-frequency repetitive transcranial magnetic stimulation can similarly improve upper-limb motor function in patients with cerebral infarction.

  17. Ultrafast high-repetition imaging of fuel sprays using picosecond fiber laser.

    PubMed

    Purwar, Harsh; Wang, Hongjie; Tang, Mincheng; Idlahcen, Saïd; Rozé, Claude; Blaisot, Jean-Bernard; Godin, Thomas; Hideur, Ammar

    2015-12-28

    Modern diesel injectors operate at very high injection pressures of about 2000 bar resulting in injection velocities as high as 700 m/s near the nozzle outlet. In order to better predict the behavior of the atomization process at such high pressures, high-resolution spray images at high repetition rates must be recorded. However, due to extremely high velocity in the near-nozzle region, high-speed cameras fail to avoid blurring of the structures in the spray images due to their exposure time. Ultrafast imaging featuring ultra-short laser pulses to freeze the motion of the spray appears as an well suited solution to overcome this limitation. However, most commercial high-energy ultrafast sources are limited to a few kHz repetition rates. In the present work, we report the development of a custom-designed picosecond fiber laser generating ∼ 20 ps pulses with an average power of 2.5 W at a repetition rate of 8.2 MHz, suitable for high-speed imaging of high-pressure fuel jets. This fiber source has been proof tested by obtaining backlight images of diesel sprays issued from a single-orifice injector at an injection pressure of 300 bar. We observed a consequent improvement in terms of image resolution compared to standard white-light illumination. In addition, the compactness and stability against perturbations of our fiber laser system makes it particularly suitable for harsh experimental conditions.

  18. A comparison of stapedial reflex fatigue with repetitive stimulation and single-fiber EMG in myasthenia gravis.

    PubMed

    Kramer, L D; Ruth, R A; Johns, M E; Sanders, D B

    1981-06-01

    The pattern of stapedial reflex fatigue in response to pulsed acoustic stimulation was measured and compared to results of repetitive nerve stimulation and single-fiber electromyography (EMG) in 89 patients with myasthenia gravis. Studies were also made on 22 patients with other neuromuscular disorders and 40 control subjects with no evidence of neuromuscular impairment. Stapedial reflex fatigue exceeded normal control values in 84% of the patients with myasthenia gravis. Repetitive stimulation and single-fiber EMG measurements were abnormal in 56% and 91% of this same population, respectively. Stapedial reflex abnormalities were most prevalent in patients with mild forms of myasthenia (predominantly ocular or oropharyngeal weakness). Of 22 nonmyasthenic patients with neuromuscular disease tested, 6 had abnormal stapedial reflex fatigue according to our normal values, indicating that this form of testing also detects other diseases of the motor unit. The measurement of stapedial reflex fatigue is painless, is easy to perform, and requires minimal patient cooperation. Due to the relatively high occurrence of abnormal stapedial reflex fatigue in patients with myasthenia gravis, this procedure appears to have considerable potential value in screening and monitoring patients for the presence of defects in neuromuscular transmission.

  19. Low and High Frequency Repetitive Transcranial Magnetic Stimulation for the Treatment of Spasticity

    ERIC Educational Resources Information Center

    Valle, Angela C.; Dionisio, Karen; Pitskel, Naomi Bass; Pascual-Leone, Alvaro; Orsati, Fernanda; Ferreira, Merari J. L.; Boggio, Paulo S.; Lima, Moises C.; Rigonatti, Sergio P.; Fregni, Felipe

    2007-01-01

    The development of non-invasive techniques of cortical stimulation, such as transcranial magnetic stimulation (TMS), has opened new potential avenues for the treatment of neuropsychiatric diseases. We hypothesized that an increase in the activity in the motor cortex by cortical stimulation would increase its inhibitory influence on spinal…

  20. Low and High Frequency Repetitive Transcranial Magnetic Stimulation for the Treatment of Spasticity

    ERIC Educational Resources Information Center

    Valle, Angela C.; Dionisio, Karen; Pitskel, Naomi Bass; Pascual-Leone, Alvaro; Orsati, Fernanda; Ferreira, Merari J. L.; Boggio, Paulo S.; Lima, Moises C.; Rigonatti, Sergio P.; Fregni, Felipe

    2007-01-01

    The development of non-invasive techniques of cortical stimulation, such as transcranial magnetic stimulation (TMS), has opened new potential avenues for the treatment of neuropsychiatric diseases. We hypothesized that an increase in the activity in the motor cortex by cortical stimulation would increase its inhibitory influence on spinal…

  1. Repetitive transcranial magnetic stimulation versus electroconvulsive therapy for major depression: a meta-analysis of stimulus parameter effects.

    PubMed

    Xie, Jing; Chen, Jianjun; Wei, Qianping

    2013-12-01

    Studies comparing the antidepressant effects of electroconvulsive therapy (ECT) and repetitive transcranial magnetic stimulation (rTMS) have reported mixed results, as the choice of rTMS stimulus parameters is essential to its antidepressive effect. This meta-analysis aimed at assessing how rTMS stimulus parameters influence the efficacy of rTMS relative to ECT in treating major depression. A comprehensive literature search (including PubMed, CCTR, Web of Science, Embase, EAGLE, NTIS, CBM-disc, CNKI, Current Controlled Trials, Clinical Trials, International Clinical Trials Registry, and Internet Stroke Center) was conducted dating until December 2012. After exclusion of low-quality studies, the key search terms ('depressive', 'depression', 'transcranial magnetic stimulation', 'TMS', 'repetitive TMS', 'electroconvulsive therapy', and 'ECT') produced nine high-quality randomized controlled trials (RCTs) of rTMS versus ECT. These nine studies, composed of 395 patients, were meta-analyzed through assessment of odds of remission, response, and drop-out. Two rTMS subgroups displayed non-significant superiority to ECT: 20 Hz (odds ratio (OR) = 1·20; P > 0·05) and ≥ 1200 daily stimuli (OR = 1·06; P > 0·05). One rTMS subgroup displayed non-significant inferiority to ECT: four-week treatment period (OR = 0·65; P > 0·05). The other rTMS subgroups were significantly inferior to ECT. Repetitive transcranial magnetic stimulation was associated with a 30% relative reduction in the odds of drop-out, however non-significantly (95% confidence interval (CI), 0·36-1·39). The results indicate that the efficacy of rTMS is tied to its stimulus parameters. Varying stimulus parameters can result in varying antidepressive effects. Consequently, future research on rTMS or rTMS versus ECT should take the influence of rTMS stimulus parameters into consideration.

  2. Effects of Repetitive Transcranial Magnetic Stimulation on Motor Symptoms in Parkinson Disease

    PubMed Central

    Chou, Ying-hui; Hickey, Patrick T.; Sundman, Mark; Song, Allen W.; Chen, Nan-kuei

    2015-01-01

    IMPORTANCE Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive neuromodulation technique that has been closely examined as a possible treatment for Parkinson disease (PD). However, results evaluating the effectiveness of rTMS in PD are mixed, mostly owing to low statistical power or variety in individual rTMS protocols. OBJECTIVES To determine the rTMS effects on motor dysfunction in patients with PD and to examine potential factors that modulate the rTMS effects. DATA SOURCES Databases searched included PubMed, EMBASE, Web of Knowledge, Scopus, and the Cochrane Library from inception to June 30, 2014. STUDY SELECTION Eligible studies included sham-controlled, randomized clinical trials of rTMS intervention for motor dysfunction in patients with PD. DATA EXTRACTION AND SYNTHESIS Relevant measures were extracted independently by 2 investigators. Standardized mean differences (SMDs) were calculated with random-effects models. MAIN OUTCOMES AND MEASURES Motor examination of the Unified Parkinson’s Disease Rating Scale. RESULTS Twenty studies with a total of 470 patients were included. Random-effects analysis revealed a pooled SMD of 0.46 (95%CI, 0.29–0.64), indicating an overall medium effect size favoring active rTMS over sham rTMS in the reduction of motor symptoms (P < .001). Subgroup analysis showed that the effect sizes estimated from high-frequency rTMS targeting the primary motor cortex (SMD, 0.77; 95%CI, 0.46–1.08; P < .001) and low-frequency rTMS applied over other frontal regions (SMD, 0.50; 95%CI, 0.13–0.87; P = .008) were significant. The effect sizes obtained from the other 2 combinations of rTMS frequency and rTMS site (ie, high-frequency rTMS at other frontal regions: SMD, 0.23; 95% CI, −0.02 to 0.48, and low primary motor cortex: SMD, 0.28; 95%CI, −0.23 to 0.78) were not significant. Meta-regression revealed that a greater number of pulses per session or across sessions is associated with larger rTMS effects. Using the

  3. Modulation of N400 in chronic non-fluent aphasia using low frequency Repetitive Transcranial Magnetic Stimulation (rTMS).

    PubMed

    Barwood, Caroline H S; Murdoch, Bruce E; Whelan, Brooke-Mai; Lloyd, David; Riek, Stephan; O'Sullivan, John D; Coulthard, Alan; Wong, Andrew

    2011-03-01

    Low frequency Repetitive Transcranial Magnetic Stimulation (rTMS) has previously been applied to language homologues in non-fluent populations of persons with aphasia yielding significant improvements in behavioral language function up to 43 months post stimulation. The present study aimed to investigate the electrophysiological correlates associated with the application of rTMS through measurement of the semantic based N400 Event-related brain potentials (ERP) component. Low frequency (1 Hz) rTMS was applied to the anterior portion of the homologue to Broca's area (pars triangularis), for 20 min per day for 10 days, using a stereotactic neuronavigational system. Twelve non-fluent persons with aphasia, 2-6 years post stroke were stimulated. Six participants were randomly assigned to receive real stimulation and six participants were randomly assigned to receive a blind sham control condition. ERP measures were recorded at baseline, 1 week and 2 months subsequent to stimulation. The findings demonstrate treatment related changes observed in the stimulation group when compared to the placebo control group at 2 months post stimulation indicating neuromodulation of N400 as a result of rTMS. No treatment related changes were identified in the stimulation group, when compared to the sham group from baseline to 1 week post stimulation. The electrophysiological results represent the capacity of rTMS to modulate neural language networks and measures of lexical-semantic function in participants with non-fluent aphasia and suggest that time may be an important factor in brain reorganization subsequent to rTMS.

  4. Effects of low- and high-frequency repetitive magnetic stimulation on neuronal cell proliferation and growth factor expression: A preliminary report.

    PubMed

    Lee, Ji Yong; Park, Hyung Joong; Kim, Ji Hyun; Cho, Byung Pil; Cho, Sung-Rae; Kim, Sung Hoon

    2015-09-14

    Repetitive magnetic stimulation is a neuropsychiatric and neurorehabilitation tool that can be used to investigate the neurobiology of sensory and motor functions. Few studies have examined the effects of repetitive magnetic stimulation on the modulation of neurotrophic/growth factors and neuronal cells in vitro. Therefore, the current study examined the differential effects of repetitive magnetic stimulation on neuronal cell proliferation as well as various growth factor expression. Immortalized mouse neuroblastoma cells were used as the cell model in this study. Dishes of cultured cells were randomly divided into control, sham, low-frequency (0.5Hz, 1Tesla) and high-frequency (10Hz, 1Tesla) groups (n=4 dishes/group) and were stimulated for 3 days. Expression of neurotrophic/growth factors, Akt and Erk was investigated by Western blotting analysis 3 days after repetitive magnetic stimulation. Neuroblastoma cell proliferation was determined with a cell counting assay. There were differences in cell proliferation based on stimulus frequency. Low-frequency stimulation did not alter proliferation relative to the control, while high-frequency stimulation elevated proliferation relative to the control group. The expression levels of brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), neurotrophin-3 (NT-3) and platelet-derived growth factor (PDGF) were elevated in the high-frequency magnetic stimulation group. Akt and Erk expression was also significantly elevated in the high-frequency stimulation group, while low-frequency stimulation decreased the expression of Akt and Erk compared to the control. In conclusion, we determined that different frequency magnetic stimulation had an influence on neuronal cell proliferation via regulation of Akt and ERK signaling pathways and the expression of growth factors such as BDNF, GDNF, NT-3 and PDGF. These findings represent a promising opportunity to gain insight into how different

  5. Chemiluminometric Immuno-Analysis of Innate Immune Response against Repetitive Bacterial Stimulations for the Same Mammalian Cells

    PubMed Central

    Jeon, Jin-Woo; Cho, Il-Hoon; Ha, Un-Hwan; Seo, Sung-Kyu; Paek, Se-Hwan

    2014-01-01

    For monitoring of human cellular response to repetitive bacterial stimulations (e.g., Pseudomonas aeruginosa in a lysate form), we devised a chemiluminescent immuno-analytical system for toll-like receptor 1 (TLR1) as marker present on cell surfaces (e.g., A549). Upon stimulation, TLR1 recognizes pathogen-associated molecular patterns of the infectious agent and are then up-regulated via activation of the nuclear factor-κB (NF-κB) pathway. In this study, the receptor density was quantified by employing an antibody specific to the target receptor and by producing a chemiluminometric signal from an enzyme labeled to the binder. The activated status was then switched back to normal down-regulated stage, by changing the culture medium to one containing animal serum. The major factors affecting activation were the stimulation dose of the bacterial lysate, stimulation timing during starvation, and up- and down-regulation time intervals. Reiterative TLR regulation switching up to three times was not affected by either antibody remained after immunoassay or enzyme substrate (e.g., hydrogen peroxide) in solution. This immuno-analysis for TLRs could be unique to acquire accumulated response of the human cells to repeated stimulations and, therefore, can eventually apply to persistency testing of the cellular regulation in screening of anti-inflammatory substances. PMID:25109895

  6. Low-frequency repetitive transcranial magnetic stimulation on Parkinson motor function: a meta-analysis of randomised controlled trials.

    PubMed

    Zhu, HongCan; Lu, ZhaoMing; Jin, YiTing; Duan, XiaoJia; Teng, JunFang; Duan, DongXiao

    2015-04-01

    Previous studies have demonstrated inconsistent findings regarding the efficacy of low-frequency repetitive transcranial magnetic stimulation (rTMS) in treating motor symptoms of Parkinson's disease (PD). Therefore, this meta-analysis was conducted to assess the efficacy of low-frequency rTMS. A comprehensive literature search (including PubMed, CCTR, Embase, Web of Science, CNKI, CBM-disc, NTIS,EAGLE, Clinical Trials, Current Controlled Trials, International Clinical Trials Registry) was conducted dating until June 2014. The key search terms ('Parkinson', 'PD', 'transcranial magnetic stimulation', 'TMS', 'RTMS' and 'noninvasive brain stimulation') produced eight high-quality randomised controlled trials (RCT) of low-frequency rTMS versus sham stimulation. These eight studies, composed of 319 patients, were meta-analysed through assessment of the decreased Unified Parkinson's Disease Rating Scale (UPDRS part III) score. Pooling of the results from these RCTs yielded an effect size of -0.40 (95%CI=-0.73 to -0.06, p<0.05) in UPDRS part III, which indicated that low-frequency rTMS could have 5.05 (95%CI=-1.73 to -8.37) point decrease in UPDRS part III score than sham stimulation. Low-frequency rTMS had a significant effect on motor signs in PD. As the number of RCTs and PD patients included here was limited, further large-scale multi-center RCTs were required to validate our conclusions.

  7. Optimal repetition rate and pulse duration studies for two photon imaging

    NASA Astrophysics Data System (ADS)

    Mirkhanov, Shamil; Quarterman, Adrian H.; Smyth, Connor J. C. P.; Praveen, Bavishna B.; Appleton, Paul; Thomson, Calum; Swift, Samuel; Wilcox, Keith G.

    2017-02-01

    Multiphoton imaging (MPI) is an important fluorescence microscopy technique that allows deep tissue and in-vivo imaging with high selectivity. According to theory, two-photon signal is proportional to the product of the peak power and the average power, allowing optimization of key imaging parameters of the excitation laser, such as average power, repetition rate and pulse duration. Recent progress in compact ultrafast lasers including femtosecond fiber lasers and optically pumped semiconductor lasers makes direct control of these parameters possible. In order to investigate the optimum laser parameters for two photon imaging we experimentally study the effects of repetition rate between 2.85 and 90 MHz and pulse duration between 336 fs and 3.5 ps on two photon signal in SYTOX Green labeled mouse intestine sections at 1030 nm. We found that the optimum repetition rate for this sample is in the range 20 - 40 MHz, depending on average power, and that the pulse duration has no effect on the MPI signal provided that the average power can be adjusted to keep the product of average and peak power constant.

  8. Repetitive Transcranial Magnetic Stimulation (rTMS) to Treat Social Anxiety Disorder: Case Reports and a Review of the Literature

    PubMed Central

    Paes, Flávia; Baczynski, Tathiana; Novaes, Felipe; Marinho, Tamires; Arias-Carrión, Oscar; Budde, Henning; Sack, Alexander T.; Huston, Joseph P.; Almada, Leonardo Ferreira; Carta, Mauro; Silva, Adriana Cardoso; Nardi, Antonio E.; Machado, Sergio

    2013-01-01

    Objectives: Social anxiety disorder (SAD) is a common and debilitating anxiety disorders. However, few studies had been dedicated to the neurobiology underlying SAD until the last decade. Rates of non-responders to standard methods of treatment remain unsatisfactorily high of approximately 25%, including SAD. Advances in our understanding of SAD could lead to new treatment strategies. A potential non invasive therapeutic option is repetitive transcranial magnetic stimulation (rTMS). Thus, we reported two cases of SAD treated with rTMS Methods: The bibliographical search used Pubmed/Medline, ISI Web of Knowledge and Scielo databases. The terms chosen for the search were: anxiety disorders, neuroimaging, repetitive transcranial magnetic stimulation. Results: In most of the studies conducted on anxiety disorders, except SAD, the right prefrontal cortex (PFC), more specifically dorsolateral PFC was stimulated, with marked results when applying high-rTMS compared with studies stimulating the opposite side. However, according to the “valence hypothesis”, anxiety disorders might be characterized by an interhemispheric imbalance associated with increased right-hemispheric activity. With regard to the two cases treated with rTMS, we found a decrease in BDI, BAI and LSAS scores from baseline to follow-up. Conclusion: We hypothesize that the application of low-rTMS over the right medial PFC (mPFC; the main structure involved in SAD circuitry) combined with high-rTMS over the left mPFC, for at least 4 weeks on consecutive weekdays, may induce a balance in brain activity, opening an attractive therapeutic option for the treatment of SAD. PMID:24278088

  9. High-Frequency Repetitive Sensory Stimulation as Intervention to Improve Sensory Loss in Patients with Complex Regional Pain Syndrome I.

    PubMed

    David, Marianne; Dinse, Hubert R; Mainka, Tina; Tegenthoff, Martin; Maier, Christoph

    2015-01-01

    Achieving perceptual gains in healthy individuals or facilitating rehabilitation in patients is generally considered to require intense training to engage neuronal plasticity mechanisms. Recent work, however, suggested that beneficial outcome similar to training can be effectively acquired by a complementary approach in which the learning occurs in response to mere exposure to repetitive sensory stimulation (rSS). For example, high-frequency repetitive sensory stimulation (HF-rSS) enhances tactile performance and induces cortical reorganization in healthy subjects and patients after stroke. Patients with complex regional pain syndrome (CRPS) show impaired tactile performance associated with shrinkage of cortical maps. We here investigated the feasibility and efficacy of HF-rSS, and low-frequency rSS (LF-rSS) to enhance tactile performance and reduce pain intensity in 20 patients with CRPS type I. Intermittent high- or low-frequency electrical stimuli were applied for 45 min/day to all fingertips of the affected hand for 5 days. Main outcome measures were spatial two-point-discrimination thresholds and mechanical detection thresholds measured on the tip of the index finger bilaterally. Secondary endpoint was current pain intensity. All measures were assessed before and on day 5 after the last stimulation session. HF-rSS applied in 16 patients improved tactile discrimination on the affected hand significantly without changes contralaterally. Current pain intensity remained unchanged on average, but decreased in four patients by ≥30%. This limited pain relief might be due to the short stimulation period of 5 days only. In contrast, after LF-rSS, tactile discrimination was impaired in all four patients, while detection thresholds and pain were not affected. Our data suggest that HF-rSS could be used as a novel approach in CRPS treatment to improve sensory loss. Longer treatment periods might be required to induce consistent pain relief.

  10. High-Frequency Repetitive Sensory Stimulation as Intervention to Improve Sensory Loss in Patients with Complex Regional Pain Syndrome I

    PubMed Central

    David, Marianne; Dinse, Hubert R.; Mainka, Tina; Tegenthoff, Martin; Maier, Christoph

    2015-01-01

    Achieving perceptual gains in healthy individuals or facilitating rehabilitation in patients is generally considered to require intense training to engage neuronal plasticity mechanisms. Recent work, however, suggested that beneficial outcome similar to training can be effectively acquired by a complementary approach in which the learning occurs in response to mere exposure to repetitive sensory stimulation (rSS). For example, high-frequency repetitive sensory stimulation (HF-rSS) enhances tactile performance and induces cortical reorganization in healthy subjects and patients after stroke. Patients with complex regional pain syndrome (CRPS) show impaired tactile performance associated with shrinkage of cortical maps. We here investigated the feasibility and efficacy of HF-rSS, and low-frequency rSS (LF-rSS) to enhance tactile performance and reduce pain intensity in 20 patients with CRPS type I. Intermittent high- or low-frequency electrical stimuli were applied for 45 min/day to all fingertips of the affected hand for 5 days. Main outcome measures were spatial two-point-discrimination thresholds and mechanical detection thresholds measured on the tip of the index finger bilaterally. Secondary endpoint was current pain intensity. All measures were assessed before and on day 5 after the last stimulation session. HF-rSS applied in 16 patients improved tactile discrimination on the affected hand significantly without changes contralaterally. Current pain intensity remained unchanged on average, but decreased in four patients by ≥30%. This limited pain relief might be due to the short stimulation period of 5 days only. In contrast, after LF-rSS, tactile discrimination was impaired in all four patients, while detection thresholds and pain were not affected. Our data suggest that HF-rSS could be used as a novel approach in CRPS treatment to improve sensory loss. Longer treatment periods might be required to induce consistent pain relief. PMID:26635719

  11. Ventrolateral prefrontal cortex repetitive transcranial magnetic stimulation in the treatment of depersonalization disorder: A consecutive case series.

    PubMed

    Jay, Emma-Louise; Nestler, Steffen; Sierra, Mauricio; McClelland, Jessica; Kekic, Maria; David, Anthony S

    2016-06-30

    Case reports and an open trial have reported promising responses to repetitive transcranial magnetic stimulation (rTMS) to prefrontal and temporo-parietal sites in patients with depersonalization disorder (DPD). We recently showed that a single session of rTMS to the ventrolateral prefrontal cortex (VLPFC) was associated with a reduction in symptoms and increase in physiological arousal. Seven patients with medication-resistant DSM-IV DPD received up to 20 sessions of right-sided rTMS to the VLPFC for 10 weeks. Stimulation was guided using neuronavigation software based on participants' individual structural MRIs, and delivered at 110% of resting motor threshold. A session consisted of 1Hz repetitive TMS for 15min. The primary outcome measure was reduction in depersonalization symptoms on the Cambridge Depersonalization Scale (CDS). Secondary outcomes included scores on the Beck Depression Inventory (BDI) and Beck Anxiety Inventory (BAI). 20 sessions of rTMS treatment to right VLPFC significantly reduced scores on the CDS by on average 44% (range 2-83.5%). Two patients could be classified as "full responders", four as "partial" and one a non-responder. Response usually occurred within the first 6 sessions. There were no significant adverse events. A randomized controlled clinical trial of VLPFC rTMS for DPD is warranted.

  12. Within-session sensitization and between-session habituation: a robust physiological response to repetitive painful heat stimulation.

    PubMed

    May, A; Rodriguez-Raecke, R; Schulte, A; Ihle, K; Breimhorst, M; Birklein, F; Jürgens, T P

    2012-03-01

    Habituation and sensitization are important behavioural responses to repeated exposure of painful stimuli. Whereas within-session response dynamics to nociceptive stimuli is well characterized, little is known about long-term behaviour due to repetitive nociceptive stimulation. We used a standardized longitudinal heat pain paradigm in 66 healthy participants, 21 patients with chronic low back pain and 22 patients with depression who received daily sessions of 60 suprathreshold heat stimuli (48 °C each) for eight consecutive days. All three groups showed the same response: Repeated painful stimulation over several days resulted in substantially decreased pain ratings to identical painful stimuli. The decreased perception of pain over time was associated with a very robust increase in pain ratings in each single pain session, i.e., all participants sensitized within sessions and habituated between sessions. This uniform pattern was equally present in all examined groups. Chronic pain and depression do not seem to interfere with short-term sensitization and long-term habituation in this model of repetitive phasic heat pain.

  13. The Effect of High-Frequency Repetitive Transcranial Magnetic Stimulation on Occupational Stress among Health Care Workers: A Pilot Study

    PubMed Central

    Kim, Young In; Kim, Hyungjin; Han, Doug Hyun

    2016-01-01

    Objective Repetitive transcranial magnetic stimulation (rTMS) was approved by the Food and Drug Administration to alleviate symptoms of treatment-resistant depression. This study aimed to evaluate the effectiveness of rTMS treatment on alleviating occupational stress by evaluating clinical symptoms and quantitative electroencephalography (QEEG). Methods Twenty-four health care workers were randomized to receive 12 sessions of active or sham rTMS delivered to the left dorsolateral prefrontal cortex (DLPFC). Each session consisted of 32 trains of 10 Hz repetitive TMS delivered in 5-second trains at 110% of the estimated prefrontal cortex threshold. Before and after the intervention, the Korean version of the occupational stress inventory (K-OSI), Beck's depression inventory (BDI), and Beck's anxiety inventory (BAI) were administered and EEG was performed using a 21-channel digital EEG system. Results After TMS, the average scores for the affective responses to stressors on the personal strain questionnaire (PSQ) subscale of K-OSI and BDI decreased significantly for the active-TMS group compared to the sham-TMS group. Also, the active-TMS group showed a significantly greater decrease in relative alpha in the F3 electrode and a significantly greater increase in the F4 electrode. Conclusion High-frequency rTMS on the left DLPFC had stress-relieving and mood-elevating effects in health care workers, likely by stimulating the left frontal lobe. PMID:27909453

  14. The Effect of High-Frequency Repetitive Transcranial Magnetic Stimulation on Occupational Stress among Health Care Workers: A Pilot Study.

    PubMed

    Kim, Young In; Kim, Sun Mi; Kim, Hyungjin; Han, Doug Hyun

    2016-11-01

    Repetitive transcranial magnetic stimulation (rTMS) was approved by the Food and Drug Administration to alleviate symptoms of treatment-resistant depression. This study aimed to evaluate the effectiveness of rTMS treatment on alleviating occupational stress by evaluating clinical symptoms and quantitative electroencephalography (QEEG). Twenty-four health care workers were randomized to receive 12 sessions of active or sham rTMS delivered to the left dorsolateral prefrontal cortex (DLPFC). Each session consisted of 32 trains of 10 Hz repetitive TMS delivered in 5-second trains at 110% of the estimated prefrontal cortex threshold. Before and after the intervention, the Korean version of the occupational stress inventory (K-OSI), Beck's depression inventory (BDI), and Beck's anxiety inventory (BAI) were administered and EEG was performed using a 21-channel digital EEG system. After TMS, the average scores for the affective responses to stressors on the personal strain questionnaire (PSQ) subscale of K-OSI and BDI decreased significantly for the active-TMS group compared to the sham-TMS group. Also, the active-TMS group showed a significantly greater decrease in relative alpha in the F3 electrode and a significantly greater increase in the F4 electrode. High-frequency rTMS on the left DLPFC had stress-relieving and mood-elevating effects in health care workers, likely by stimulating the left frontal lobe.

  15. Preliminary Evidence of the Effects of High-frequency Repetitive Transcranial Magnetic Stimulation (rTMS) on Swallowing Functions in Post-Stroke Individuals with Chronic Dysphagia

    ERIC Educational Resources Information Center

    Cheng, Ivy K. Y.; Chan, Karen M. K.; Wong, C. S.; Cheung, Raymond T. F.

    2015-01-01

    Background: There is growing evidence of potential benefits of repetitive transcranial magnetic stimulation (rTMS) in the rehabilitation of dysphagia. However, the site and frequency of stimulation for optimal effects are not clear. Aims: The aim of this pilot study is to investigate the short-term effects of high-frequency 5 Hz rTMS applied to…

  16. Preliminary Evidence of the Effects of High-frequency Repetitive Transcranial Magnetic Stimulation (rTMS) on Swallowing Functions in Post-Stroke Individuals with Chronic Dysphagia

    ERIC Educational Resources Information Center

    Cheng, Ivy K. Y.; Chan, Karen M. K.; Wong, C. S.; Cheung, Raymond T. F.

    2015-01-01

    Background: There is growing evidence of potential benefits of repetitive transcranial magnetic stimulation (rTMS) in the rehabilitation of dysphagia. However, the site and frequency of stimulation for optimal effects are not clear. Aims: The aim of this pilot study is to investigate the short-term effects of high-frequency 5 Hz rTMS applied to…

  17. A comparison of the effects of repetitive transcranial magnetic stimulation (rTMS) by number of stimulation sessions on hemispatial neglect in chronic stroke patients.

    PubMed

    Kim, Yong Kyun; Jung, Jae Hwan; Shin, Sung Hun

    2015-01-01

    We investigated the effect of repetitive transcranial magnetic stimulation (rTMS) applied either during one session of stimulation, or by ten sessions of low-frequency stimulation over the left parietal cortex, on hemispatial neglect in stroke patients. We enrolled 34 subjects that had experienced a stroke. All subjects received 1,200 real rTMS over the left parietal cortex at an intensity of 90% of motor thresholds with 1 Hz. Subjects were divided into two groups. One group of subjects (n = 19) received real rTMS over the left parietal cortex in a single session of stimulation, and the other group (n = 15), underwent a total of ten sessions of daily stimulations for 2 weeks. Letter cancelation test, line bisection test, and Ota's task were administered to compare the effects of different rTMS protocols, before and after rTMS. The results showed no difference in baseline value between the single session group and the ten sessions group. Total ten sessions of low-frequency rTMS over the left parietal cortex, compared with the single session of rTMS, significantly improved hemispatial neglect in letter cancelation, line bisection, and Ota's task (P < 0.01). Finally, a total of ten sessions of low-frequency rTMS can be used in treatment by rTMS for patients suffering from hemispatial neglect after stroke.

  18. Repetitive transcranial magnetic stimulation for the treatment of major depressive disorder: an evidence-based analysis.

    PubMed

    2004-01-01

    This review was conducted to assess the effectiveness of repetitive transcranial magnetic stimulation (rTMS) in the treatment of major depressive disorder (MDD). rTMS is a noninvasive way to stimulate nerve cells in areas of the brain. During rTMS, an electrical current passes through a wire coil placed over the scalp. The current induces a magnetic field that produces an electrical field in the brain that then causes nerve cells to depolarize, resulting in the stimulation or disruption of brain activity. Researchers have investigated rTMS as an option to treat MDD, as an add-on to drug therapy, and, in particular, as an alternative to electroconvulsive therapy (ECT) for patients with treatment-resistant depression. The advantages of rTMS over ECT for patients with severe refractory depression are that general anesthesia is not needed, it is an outpatient procedure, it requires less energy, the simulation is specific and targeted, and convulsion is not required. The advantages of rTMS as an add-on treatment to drug therapy may include hastening of the clinical response when used with antidepressant drugs. The Medical Advisory Secretariat used its standard search strategy to locate international health technology assessments and English-language journal articles published from January 1996 to March 2004. Some early meta-analyses suggested rTMS might be effective for the treatment of MDD (for treatment-resistant MDD and as an add-on treatment to drug therapy for patients not specifically defined as treatment resistant). There were, however, several crucial methodological limitations in the included studies that were not critically assessed. These are discussed below. Recent meta-analyses (including 2 international health technology assessments) have done evidence-based critical analyses of studies that have assessed rTMS for MDD. The 2 most recent health technology assessments (from the Oxford Cochrane Collaboration and the Norwegian Centre for Health Technology

  19. Utilizing repetitive transcranial magnetic stimulation to improve language function in stroke patients with chronic non-fluent aphasia.

    PubMed

    Garcia, Gabriella; Norise, Catherine; Faseyitan, Olufunsho; Naeser, Margaret A; Hamilton, Roy H

    2013-07-02

    Transcranial magnetic stimulation (TMS) has been shown to significantly improve language function in patients with non-fluent aphasia(1). In this experiment, we demonstrate the administration of low-frequency repetitive TMS (rTMS) to an optimal stimulation site in the right hemisphere in patients with chronic non-fluent aphasia. A battery of standardized language measures is administered in order to assess baseline performance. Patients are subsequently randomized to either receive real rTMS or initial sham stimulation. Patients in the real stimulation undergo a site-finding phase, comprised of a series of six rTMS sessions administered over five days; stimulation is delivered to a different site in the right frontal lobe during each of these sessions. Each site-finding session consists of 600 pulses of 1 Hz rTMS, preceded and followed by a picture-naming task. By comparing the degree of transient change in naming ability elicited by stimulation of candidate sites, we are able to locate the area of optimal response for each individual patient. We then administer rTMS to this site during the treatment phase. During treatment, patients undergo a total of ten days of stimulation over the span of two weeks; each session is comprised of 20 min of 1 Hz rTMS delivered at 90% resting motor threshold. Stimulation is paired with an fMRI-naming task on the first and last days of treatment. After the treatment phase is complete, the language battery obtained at baseline is repeated two and six months following stimulation in order to identify rTMS-induced changes in performance. The fMRI-naming task is also repeated two and six months following treatment. Patients who are randomized to the sham arm of the study undergo sham site-finding, sham treatment, fMRI-naming studies, and repeat language testing two months after completing sham treatment. Sham patients then cross over into the real stimulation arm, completing real site-finding, real treatment, fMRI, and two- and six

  20. Utilizing Repetitive Transcranial Magnetic Stimulation to Improve Language Function in Stroke Patients with Chronic Non-fluent Aphasia

    PubMed Central

    Garcia, Gabriella; Norise, Catherine; Faseyitan, Olufunsho; Naeser, Margaret A.; Hamilton, Roy H.

    2013-01-01

    Transcranial magnetic stimulation (TMS) has been shown to significantly improve language function in patients with non-fluent aphasia1. In this experiment, we demonstrate the administration of low-frequency repetitive TMS (rTMS) to an optimal stimulation site in the right hemisphere in patients with chronic non-fluent aphasia. A battery of standardized language measures is administered in order to assess baseline performance. Patients are subsequently randomized to either receive real rTMS or initial sham stimulation. Patients in the real stimulation undergo a site-finding phase, comprised of a series of six rTMS sessions administered over five days; stimulation is delivered to a different site in the right frontal lobe during each of these sessions. Each site-finding session consists of 600 pulses of 1 Hz rTMS, preceded and followed by a picture-naming task. By comparing the degree of transient change in naming ability elicited by stimulation of candidate sites, we are able to locate the area of optimal response for each individual patient. We then administer rTMS to this site during the treatment phase. During treatment, patients undergo a total of ten days of stimulation over the span of two weeks; each session is comprised of 20 min of 1 Hz rTMS delivered at 90% resting motor threshold. Stimulation is paired with an fMRI-naming task on the first and last days of treatment. After the treatment phase is complete, the language battery obtained at baseline is repeated two and six months following stimulation in order to identify rTMS-induced changes in performance. The fMRI-naming task is also repeated two and six months following treatment. Patients who are randomized to the sham arm of the study undergo sham site-finding, sham treatment, fMRI-naming studies, and repeat language testing two months after completing sham treatment. Sham patients then cross over into the real stimulation arm, completing real site-finding, real treatment, fMRI, and two- and six

  1. The effects of low frequency Repetitive Transcranial Magnetic Stimulation (rTMS) and sham condition rTMS on behavioural language in chronic non-fluent aphasia: Short term outcomes.

    PubMed

    Barwood, Caroline H S; Murdoch, Bruce E; Whelan, Brooke-Mai; Lloyd, David; Riek, Stephan; O'Sullivan, John; Coulthard, Alan; Wong, Andrew; Aitken, Phil; Hall, Graham

    2011-01-01

    The application of low frequency (1 Hz) Repetitive Transcranial Magnetic Stimulation (rTMS) to right hemisphere (RH) language homologues in non-fluent aphasic populations has yielded improvements in behavioural language function, up to 43 months post stimulation. Functional imaging studies have demonstrated RH language homologue "overactivation" post left inferior frontal gyrus (IFG) damage, in chronic non-fluent aphasia. The effects of low frequency (inhibitory) rTMS are postulated to be as a result of a reduction of overactivation in RH language homologues, facilitating the reorganisation of neural language networks. Low frequency (1 Hz) rTMS was applied to the anterior portion of a Broca's area homologue (pars triangularis), for 20 minutes per day for 10 days, using a stereotactic neuronavigational system. Twelve non-fluent aphasic patients (six real stimulation and six sham), 2-10 years post stroke were stimulated. Behavioural language outcome measures were taken at baseline and 1 week post rTMS. Comparisons between the real stimulation and sham conditions indicated significant main effects between the stimulation and sham groups to 1 week post stimulation for naming accuracy, latency and repetition. This study indicates that rTMS has the capacity to modulate neural language networks, to facilitate improvements in behavioural language function, 1 week post TMS.

  2. High frequency repetitive sensory stimulation improves temporal discrimination in healthy subjects.

    PubMed

    Erro, Roberto; Rocchi, Lorenzo; Antelmi, Elena; Palladino, Raffaele; Tinazzi, Michele; Rothwell, John; Bhatia, Kailash P

    2016-01-01

    High frequency electrical stimulation of an area of skin on a finger improves two-point spatial discrimination in the stimulated area, likely depending on plastic changes in the somatosensory cortex. However, it is unknown whether improvement also applies to temporal discrimination. Twelve young and ten elderly volunteers underwent the stimulation protocol onto the palmar skin of the right index finger. Somatosensory temporal discrimination threshold (STDT) was evaluated before and immediately after stimulation as well as 2.5h and 24h later. There was a significant reduction in somatosensory temporal threshold only on the stimulated finger. The effect was reversible, with STDT returning to the baseline values within 24h, and was smaller in the elderly than in the young participants. High frequency stimulation of the skin focally improves temporal discrimination in the area of stimulation. Given previous suggestions that the perceptual effects rely on plastic changes in the somatosensory cortex, our results are consistent with the idea that the timing of sensory stimuli is, at least partially, encoded in the primary somatosensory cortex. Such a protocol could potentially be used as a therapeutic intervention to ameliorate physiological decline in the elderly or in other disorders of sensorimotor integration. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  3. Blood flow and oxygenation changes due to low-frequency repetitive transcranial magnetic stimulation of the cerebral cortex

    NASA Astrophysics Data System (ADS)

    Mesquita, Rickson C.; Faseyitan, Olufunsho K.; Turkeltaub, Peter E.; Buckley, Erin M.; Thomas, Amy; Kim, Meeri N.; Durduran, Turgut; Greenberg, Joel H.; Detre, John A.; Yodh, Arjun G.; Hamilton, Roy H.

    2013-06-01

    Transcranial magnetic stimulation (TMS) modulates processing in the human brain and is therefore of interest as a treatment modality for neurologic conditions. During TMS administration, an electric current passing through a coil on the scalp creates a rapidly varying magnetic field that induces currents in the cerebral cortex. The effects of low-frequency (1 Hz), repetitive TMS (rTMS) on motor cortex cerebral blood flow (CBF) and tissue oxygenation in seven healthy adults, during/after 20 min stimulation, is reported. Noninvasive optical methods are employed: diffuse correlation spectroscopy (DCS) for blood flow and diffuse optical spectroscopy (DOS) for hemoglobin concentrations. A significant increase in median CBF (33%) on the side ipsilateral to stimulation was observed during rTMS and persisted after discontinuation. The measured hemodynamic parameter variations enabled computation of relative changes in cerebral metabolic rate of oxygen consumption during rTMS, which increased significantly (28%) in the stimulated hemisphere. By contrast, hemodynamic changes from baseline were not observed contralateral to rTMS administration (all parameters, p>0.29). In total, these findings provide new information about hemodynamic/metabolic responses to low-frequency rTMS and, importantly, demonstrate the feasibility of DCS/DOS for noninvasive monitoring of TMS-induced physiologic effects.

  4. Inducing transient language disruptions by mapping of Broca's area with modified patterned repetitive transcranial magnetic stimulation protocol.

    PubMed

    Rogić, Maja; Deletis, Vedran; Fernández-Conejero, Isabel

    2014-05-01

    Until now there has been no reliable stimulation protocol for inducing transient language disruptions while mapping Broca's area. Despite the promising data of only a few studies in which speech arrest and language disturbances have been induced, certain concerns have been raised. The purpose of this study was to map Broca's area by using event-related navigated transcranial magnetic stimulation (nTMS) to generate a modified patterned nTMS protocol. Eleven right-handed subjects underwent nTMS to Broca's area while engaged in a visual object-naming task. Navigated TMS was triggered 300 msec after picture presentation. The modified patterned nTMS protocol consists of 4 stimuli with an interstimulus interval of 6 msec; 8 or 16 of those bursts were repeated with a burst repetition rate of 12 Hz. Prior to mapping of Broca's area, the primary motor cortices (M1) for hand and laryngeal muscles were mapped. The Euclidian distance on MRI was measured between cortical points eliciting transient language disruptions and M1 for the laryngeal muscle. On stimulating Broca's area, transient language disruptions were induced in all subjects. The mean Euclidian distance between cortical spots inducing transient language disruptions and M1 for the laryngeal muscle was 17.23 ± 4.73 mm. The stimulation paradigm with the modified patterned nTMS protocol was shown to be promising and might gain more widespread use in speech localization in clinical and research applications.

  5. Inhibitory repetitive transcranial magnetic stimulation (rTMS) of the dorsolateral prefrontal cortex modulates early affective processing.

    PubMed

    Zwanzger, Peter; Steinberg, Christian; Rehbein, Maimu Alissa; Bröckelmann, Ann-Kathrin; Dobel, Christian; Zavorotnyy, Maxim; Domschke, Katharina; Junghöfer, Markus

    2014-11-01

    The dorsolateral prefrontal cortex (dlPFC) has often been suggested as a key modulator of emotional stimulus appraisal and regulation. Therefore, in clinical trials, it is one of the most frequently targeted regions for non-invasive brain stimulation such as repetitive transcranial magnetic stimulation (rTMS). In spite of various encouraging reports that demonstrate beneficial effects of rTMS in anxiety disorders, psychophysiological studies exploring the underlying neural mechanisms are sparse. Here we investigated how inhibitory rTMS influences early affective processing when applied over the right dlPFC. Before and after rTMS or sham stimulation, subjects viewed faces with fearful or neutral expressions while whole-head magnetoencephalography (MEG) was recorded. Due to the disrupted functioning of the right dlPFC, visual processing in bilateral parietal, temporal, and occipital areas was amplified starting at around 90 ms after stimulus onset. Moreover, increased fear-specific activation was found in the right TPJ area in a time-interval between 110 and 170 ms. These neurophysiological effects were reflected in slowed reaction times for fearful, but not for neutral faces in a facial expression identification task while there was no such effect on a gender discrimination control task. Our study confirms the specific and important role of the dlPFC in regulation of early emotional attention and encourages future clinical research to use minimal invasive methods such as transcranial magnetic (TMS) or direct current stimulation (tDCS).

  6. Neural correlates associated with symptom provocation in pediatric obsessive compulsive disorder after a single session of sham-controlled repetitive transcranial magnetic stimulation.

    PubMed

    Pedapati, Ernest; DiFrancesco, Mark; Wu, Steve; Giovanetti, Cathy; Nash, Tiffany; Mantovani, Antonio; Ammerman, Robert; Harris, Elana

    2015-09-30

    Treatments for pediatric obsessive-compulsive disorder (OCD) could be enhanced if the physiological changes engendered by treatment were known. This study examined neural correlates of a provocation task in youth with OCD, before and after sham-controlled repetitive transcranial magnetic stimulation (rTMS). We hypothesized that rTMS to the right dorsolateral prefrontal cortex would inhibit activity in cortico-striato-thalamic (CST) circuits associated with OCD to a greater extent than sham rTMS. After baseline (Time 1) functional magnetic resonance imaging (fMRI) during a provocation task, subjects received one session of either fMRI-guided sham (SG; n=8) or active (AG; n=10) 1-Hz rTMS over the rDLPFC for 30min. During rTMS, subjects were presented with personalized images that evoked OCD-related anxiety. Following stimulation, fMRI and the provocation task were repeated (Time 2). Contrary to our prediction for the provocation task, the AG was associated with no changes in BOLD response from Times 1 to 2. In contrast, the SG had a significant increase at Time 2 in BOLD response in the right inferior frontal gyrus and right putamen, which persisted after adjusting for age, gender, and time to scanner as covariates. This study provides an initial framework for TMS interrogation of the CST circuit in pediatric OCD.

  7. Strength-Duration Relationship in Paired-pulse Transcranial Magnetic Stimulation (TMS) and Its Implications for Repetitive TMS.

    PubMed

    Shirota, Yuichiro; Sommer, Martin; Paulus, Walter

    2016-01-01

    Paired-pulse protocols have played a pivotal role in neuroscience research using transcranial magnetic stimulation (TMS). Stimulus parameters have been optimized over the years. More recently, pulse width (PW) has been introduced to this field as a new parameter, which may further fine-tune paired-pulse protocols. The relationship between the PW and effectiveness of a stimulus is known as the "strength-duration relationship". To test the "strength-duration relationship", so as to improve paired-pulse TMS protocols, and to apply the results to develop new repetitive TMS (rTMS) methods. Four protocols were investigated separately: short-interval intracortical inhibition (SICI), intracortical facilitation (ICF), short-interval intracortical facilitation (SICF) and long-interval intracortical inhibition (LICI). First, various stimulus parameters were tested to identify those yielding the largest facilitation or inhibition of the motor evoked potential (MEP) in each participant. Using these parameters, paired-pulse stimulations were repeated every five seconds for 30 minutes (repetitive paired-pulse stimulation, rPPS). The after-effects of rPPS were measured using MEP amplitude as an index of motor-cortical excitability. Altogether, the effect of changing PW was similar to that of changing the stimulus intensity in the conventional settings. The best parameters were different for each participant. When these parameters were used, rPPS based on either SICF or ICF induced an increase in MEP amplitude. PW was introduced as a new parameter in paired-pulse TMS. Modulation of PW influenced the results of paired-pulse protocols. rPPS using facilitatory protocols can be a good candidate to induce enhancement of motor-cortical excitability. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Stimulated Raman scattering microscopy for biomedical imaging

    NASA Astrophysics Data System (ADS)

    Min, Wei; Freudiger, Christian W.; Lu, Sijia; He, Chengwei; Kang, Jing X.; Xie, X. Sunney

    2009-02-01

    Label-free chemical contrast is highly desirable in biomedical imaging. Spontaneous Raman microscopy provides specific vibrational signatures of chemical bonds, but is often hindered by low sensitivity. Here we report a 3D multi-photon vibrational imaging technique based on stimulated Raman scattering (SRS). The sensitivity of SRS is significantly greater than that of spontaneous Raman scattering, and is further enhanced by high-frequency (MHz) phase-sensitive detection. SRS microscopy has a major advantage over previous coherent Raman techniques in that it offers background-free and easily interpretable chemical contrast. We show a variety of biomedical applications, such as differentiating distributions of omega-3 fatty acids and saturated lipids in living cells, imaging of brain and skin tissues based on intrinsic lipid contrast.

  9. Transcranial direct current stimulation (tDCS) priming of 1Hz repetitive transcranial magnetic stimulation (rTMS) modulates experimental pain thresholds.

    PubMed

    Moloney, Tonya M; Witney, Alice G

    2013-02-08

    Transcranial direct current stimulation (tDCS) and repetitive transcranial magnetic stimulation (rTMS) of primary motor cortex (M1) modulate cortical excitability. Both techniques have been demonstrated to modulate chronic pain and experimental pain thresholds, but with inconsistent effects. Preconditioning M1 with weak tDCS (1mA) standardizes the effects of subsequent stimulation via rTMS on levels of cortical excitability. Here we examine whether 1Hz rTMS, primed with tDCS, could effectively standardize the modulation of pain thresholds. Thermal pain thresholds were determined using quantitative sensory testing (QST) of the palmar thenar of both hands in 12 healthy males pre and post tDCS - 1Hz rTMS over the hand area of the left M1. Cathodal tDCS preconditioning of 1Hz rTMS successfully reversed the normal suppressive effect of low frequency rTMS and effectively modulated cold and heat pain thresholds. Conversely, anodal tDCS - 1Hz rTMS led to a decrease in cold pain thresholds. Therefore, this study supports that preconditioning M1 using cathodal tDCS before subsequent stimulation via 1Hz rTMS facilitates the production of analgesia.

  10. Research of application of high-repetition-rate green laser in underwater imaging system

    NASA Astrophysics Data System (ADS)

    Han, Jie-fei; Luo, Tao; Sun, Li-ying; Ding, Chi-zhu; Xia, Min; Yang, Ke-cheng

    2013-09-01

    It is commonly known that absorption and scattering are the main causes of reducing performance of imaging system, especially imaging distance and resolution. Generally, various techniques are applied to decrease the effect of scattering, such as synchronous scanning and range-gated technique. Continuous-laser imaging technique meets requirements of imaging objects in the large field of view in real time, but imaging distance is less than 2 attenuation lengths in natural water. High-repetition-rate green laser, called quasi-continuous wave (QCW) green laser, is a better light source for underwater imaging. It has 1 kHz-100 kHz modulated rate, and its single pulse peak power is KW magnitude, which can be applied to range-gated imaging as Canadian LUCIE system. In addition, its polarization property is excellent for underwater polarization imaging. Therefore, it has enormous potential to underwater imaging. In order to realize its performance in underwater imaging system, we setup a separated underwater staring imaging system. For this system, a theoretic model is built by the lidar equation and optic transmission theory, and the system is evaluated by modulation transfer function (MTF). The effects of laser and receiver's parameters for the system are analyzed. Then the comparative experiments are conducted in turbid water in laboratory. The results indicate that high pulse energy improves imaging distance. Aperture and polarization could reduce the effect of scattering effectively in staring system. The result shows that this underwater system performs better by choosing suitable parameters of source and receiver.

  11. Muscle training with repetitive magnetic stimulation of the quadriceps in severe COPD patients.

    PubMed

    Bustamante, Víctor; López de Santa María, Elena; Gorostiza, Amaia; Jiménez, Unai; Gáldiz, Juan B

    2010-02-01

    Previous studies have used electrical neuromuscular stimulation as a physical training method in patients with severe COPD. We introduce the use of the more tolerable magnetic stimulation for the same purpose, investigating the effectiveness of an eight-week protocol. Eighteen patients with severe COPD were randomly assigned to a magnetic stimulation training protocol, n=10, FEV(1)=30% (SD: 7) or to parallel clinical monitoring, control group, n=8, FEV(1)=35% (SD: 8). During eight weeks, patients were stimulated for 15min on each quadriceps femoris, three times per week. Quadriceps muscle strength and endurance measurements, quality-of-life questionnaires (SF36, SGRQ) and a six-minute walking test were all carried out before and after the training period in the stimulated and control subjects. All patients completed the training with increasing intensity of stimulation, displaying a significant improvement in voluntary quadriceps strength (17.5% of the baseline value) and exercise capacity, with a mean increase of 23m in the six-minute walking test. The questionnaire scores showed greater increases in quality-of-life scores in the trained subjects compared to the controls, particularly in the physical function areas: mean increments in SF36 in "physical function": +26, "role limitations due to physical problems": +40 and "vitality": +17.5, while +13, -4 and +1, respectively in controls. Saint George's "Activity" score improved by 19.6 points, for 11.5 in controls. In COPD patients who are limited due to dyspnoea, magnetic neuromuscular stimulation of the quadriceps constitutes a feasible training method for the lower limbs, with positive effects on the muscle function, effort capacity and perception areas.

  12. Effects of shifts in the rate of repetitive stimulation on sustained attention

    NASA Technical Reports Server (NTRS)

    Krulewitz, J. E.; Warm, J. S.; Wohl, T. H.

    1975-01-01

    The effects of shifts in the rate of presentation of repetitive neutral events (background event rate) were studied in a visual vigilance task. Four groups of subjects experienced either a high (21 events/min) or a low (6 events/min) event rate for 20 min and then experienced either the same or the alternate event rate for an additional 40 min. The temporal occurrence of critical target signals was identical for all groups, irrespective of event rate. The density of critical signals was 12 signals/20 min. By the end of the session, shifts in event rate were associated with changes in performance which resembled contrast effects found in other experimental situations in which shift paradigms were used. Relative to constant event rate control conditions, a shift from a low to a high event rate depressed the probability of signal detections, while a shift in the opposite direction enhanced the probability of signal detections.

  13. Effects of shifts in the rate of repetitive stimulation on sustained attention

    NASA Technical Reports Server (NTRS)

    Krulewitz, J. E.; Warm, J. S.; Wohl, T. H.

    1975-01-01

    The effects of shifts in the rate of presentation of repetitive neutral events (background event rate) were studied in a visual vigilance task. Four groups of subjects experienced either a high (21 events/min) or a low (6 events/min) event rate for 20 min and then experienced either the same or the alternate event rate for an additional 40 min. The temporal occurrence of critical target signals was identical for all groups, irrespective of event rate. The density of critical signals was 12 signals/20 min. By the end of the session, shifts in event rate were associated with changes in performance which resembled contrast effects found in other experimental situations in which shift paradigms were used. Relative to constant event rate control conditions, a shift from a low to a high event rate depressed the probability of signal detections, while a shift in the opposite direction enhanced the probability of signal detections.

  14. Repetition suppression in transcranial magnetic stimulation-induced motor-evoked potentials is modulated by cortical inhibition.

    PubMed

    Kallioniemi, E; Pääkkönen, A; Julkunen, P

    2015-12-03

    Transcranial magnetic stimulation (TMS) can be applied to modulate cortical phenomena. The modulation effect is dependent on the applied stimulation frequency. Repetition suppression (RS) has been demonstrated in the motor system using TMS with short suprathreshold 1-Hz stimulation trains repeated at long inter-train intervals. RS has been reported to occur in the resting motor-evoked potentials (MEPs) with respect to the first pulse in a train of stimuli. Although this RS in the motor system has been described in previous studies, the neuronal origin of the phenomenon is still poorly understood. The present study evaluated RS in three TMS-induced motor responses; resting and active MEPs as well as corticospinal silent periods (SPs) in order to clarify the mechanism behind TMS-induced RS. We studied 10 healthy right-handed subjects using trains of four stimuli with stimulation intensities of 120% of the resting motor threshold (rMT) and 120% of the silent period threshold for an SP duration of 30 ms (SPT30). Inter-trial interval was 20s, with a 1-s inter-stimulus interval within the trains. We confirmed that RS appears in resting MEPs (p < 0.001), whereas active MEPs did not exhibit RS (p > 0.792). SPs, on the contrary, lengthened (p < 0.001) indicating modulation of cortical inhibition. The effects of the two stimulation intensities exhibited a similar trend; however, the SPT30 evoked a more profound inhibitory effect compared to that achieved by rMT. Moreover, the resting MEP amplitudes and SP durations correlated (rho ⩽ -0.674, p < 0.001) and the pre-TMS EMG level did not differ between stimuli in resting MEPs (F = 0.0, p ⩾ 0.999). These results imply that the attenuation of response size seen in resting MEPs might originate from increasing activity of inhibitory GABAergic interneurons which relay the characteristics of SPs.

  15. Unilateral and bilateral MRI-targeted repetitive transcranial magnetic stimulation for treatment-resistant depression: a randomized controlled study

    PubMed Central

    Blumberger, Daniel M.; Maller, Jerome J.; Thomson, Lauren; Mulsant, Benoit H.; Rajji, Tarek K.; Maher, Missy; Brown, Patrick E.; Downar, Jonathan; Vila-Rodriguez, Fidel; Fitzgerald, Paul B.; Daskalakis, Zafiris J.

    2016-01-01

    Background Several factors may mitigate the efficacy of repetitive transcranial magnetic stimulation (rTMS) over sham rTMS in patients with treatment-resistant depression (TRD). These factors include unilateral stimulation (i.e., treatment of only the left dorsolateral prefrontal cortex [DLPFC]), suboptimal methods of targeting the DLPFC and insufficient stimulation intensity (based on coil-to-cortex distance). Methods We recruited patients with TRD between the ages of 18 and 85 years from a university hospital, and participants were randomized to receive sequential bilateral rTMS (600 pulses at 1 Hz followed by 1500 pulses at 10 Hz), unilateral high-frequency left (HFL)-rTMS (2100 pulses at 10 Hz) or sham rTMS for 3 or 6 weeks depending on treatment response. Stimulation was targeted with MRI localization over the junction of the middle and anterior thirds of the middle frontal gyrus, using 120% of the coil-to-cortex adjusted motor threshold. Our primary outcome of interest was the remission rate. Results A total of 121 patients participated in this study. The remission rate was significantly higher in the bilateral group than the sham group. The remission rate in the HFL-rTMS group was intermediate and did not differ statistically from the rate in the 2 other groups. There were no significant differences in reduction of depression scores among the 3 groups. Limitations The number of pulses used per session in the unilateral group was somewhat lower in our trial than in more recent trials, and the sham condition did not involve active stimulation. Conclusion Our findings suggest that sequential bilateral rTMS is superior to sham rTMS; however, adjusting for coil-to-cortex distance did not yield enhanced efficacy rates. PMID:27269205

  16. Controlled Study of 50 Hz Repetitive Transcranial Magnetic Stimulation for the Treatment of Parkinson’s Disease

    PubMed Central

    Benninger, David H.; Iseki, Kazumi; Kranick, Sarah; Luckenbaugh, David A.; Houdayer, Elise; Hallett, Mark

    2014-01-01

    Objective To investigate the safety and efficacy of 50Hz repetitive Transcranial Magnetic Stimulation(rTMS) in the treatment of motor symptoms in Parkinson’s disease(PD). Background Progression of PD is characterized by the emergence of motor deficits, which eventually respond less to dopaminergic therapy and pose a therapeutic challenge. RTMS has shown promising results in improving gait, a major cause of disability, and may provide a therapeutic alternative. Controlled studies suggest increasing stimulation frequency might enhance therapeutic efficacy. Methods In this randomized, double blind, sham-controlled study, we investigated safety and efficacy of 50Hz-rTMS of the motor cortices in 8sessions over 2weeks. Assessment of safety and clinical efficacy over a 1-month period included timed tests of gait and bradykinesia, UPDRS and additional clinical, neurophysiological and neuropsychological parameters. In addition, safety of 50Hz-rTMS was tested with EMG-EEG-monitoring during and after stimulation. Results We investigated 26 patients with mild to moderate PD: 13 received 50Hz-rTMS and 13 sham-stimulation. 50Hz-rTMS did not improve gait, bradykinesia, global and motor UPDRS, but there appeared a short-lived “on”-state improvement in activities of daily living (UPDRS II). 50Hz-rTMS lengthened the cortical silent period, but other neurophysiology and neuropsychological measures remained unchanged. EMG/EEG recorded no pathological increase of cortical excitability or epileptic activity. There were no adverse effects. Conclusion 50Hz-rTMS of the motor cortices appears safe, but fails to improve motor performance and functional status in PD. Prolonged stimulation or other techniques with rTMS might be more efficacious, but need to be established in future research. PMID:22593114

  17. Effects of Repetitive Transcranial Magnetic Stimulation in the Rehabilitation of Communication and Deglutition Disorders: Systematic Review of Randomized Controlled Trials.

    PubMed

    Gadenz, Camila Dalbosco; Moreira, Tais de Campos; Capobianco, Dirce Maria; Cassol, Mauriceia

    2015-01-01

    To systematically review randomized controlled trials that evaluate the effects of repetitive transcranial magnetic stimulation (rTMS) on rehabilitation aspects related to communication and swallowing functions. A search was conducted on PubMed, Clinical Trials, Cochrane Library, and ASHA electronic databases. Studies were judged according to the eligibility criteria and analyzed by 2 independent and blinded researchers. We analyzed 9 studies: 4 about aphasia, 3 about dysphagia, 1 about dysarthria in Parkinson's disease and 1 about linguistic deficits in Alzheimer's disease. All aphasia studies used low-frequency rTMS to stimulate Broca's homologous area. High-frequency rTMS was applied over the pharyngoesophageal cortex from the left and/or right hemisphere in the dysphagia studies and over the left dorsolateral prefrontal cortex in the Parkinson's and Alzheimer's studies. Two aphasia and all dysphagia studies showed a significant improvement of the disorder, compared to the sham group. The other 2 studies related to aphasia found a benefit restricted to subgroups with a severe case or injury on the anterior portion of the language cortical area, respectively, whereas the Alzheimer's study demonstrated positive effects specific to auditory comprehension. There were no changes for vocal function in the Parkinson's study. The benefits of the technique and its applicability in neurogenic disorders related to communication and deglutition are still uncertain. Therefore, other randomized controlled trials are needed to clarify the optimal stimulation protocol for each disorder studied and its real effects. © 2015 S. Karger AG, Basel.

  18. Empathy Moderates the Effect of Repetitive Transcranial Magnetic Stimulation of the Right Dorsolateral Prefrontal Cortex on Costly Punishment

    PubMed Central

    Heinisch, Christine; Tas, Cumhur; Wischniewski, Julia; Güntürkün, Onur

    2012-01-01

    Humans incur considerable costs to punish unfairness directed towards themselves or others. Recent studies using repetitive transcranial magnetic stimulation (rTMS) suggest that the right dorsolateral prefrontal cortex (DLPFC) is causally involved in such strategic decisions. Presently, two partly divergent hypotheses are discussed, suggesting either that the right DLPFC is necessary to control selfish motives by implementing culturally transmitted social norms, or is involved in suppressing emotion-driven prepotent responses to perceived unfairness. Accordingly, we studied the role of the DLPFC in costly (i.e. third party) punishment by applying rTMS to the left and right DLPFC before playing a Dictator Game with the option to punish observed unfair behavior (DG-P). In addition, sham stimulation took place. Individual differences in empathy were assessed with the German version of the Interpersonal Reactivity Index. Costly punishment increased (non-significantly) upon disruption of the right – but not the left – DLPFC as compared to sham stimulation. However, empathy emerged as a highly significant moderator variable of the effect of rTMS over the right, but not left, DLPFC, suggesting that the right DLPFC is involved in controlling prepotent emotional responses to observed unfairness, depending on individual differences in empathy. PMID:23028601

  19. Long-term effects of repetitive transcranial magnetic stimulation (rTMS) in patients with chronic tinnitus.

    PubMed

    Kleinjung, Tobias; Eichhammer, Peter; Langguth, Berthold; Jacob, Peter; Marienhagen, Joerg; Hajak, Goeran; Wolf, Stephan R; Strutz, Juergen

    2005-04-01

    The pathophysiologic mechanisms of idiopathic tinnitus remain unclear. Recent studies demonstrated focal brain activation in the auditory cortex of patients with chronic tinnitus. Low-frequency repetitive transcranial magnetic stimulation (rTMS) is able to reduce cortical hyperexcitability. Fusing of the individual PET-scan with the structural MRI-scan (T1, MPRAGE) allowed us to identify exactly the area of increased metabolic activity in the auditory cortex of patients with chronic tinnitus. With the use of a neuronavigational system, this target area was exactly stimulated by the figure 8-shaped magnetic coil. In a prospective study, rTMS (110% motor threshold; 1 Hz; 2000 stimuli/day over 5 days) was performed using a placebo controlled cross-over design. Patients were blinded regarding the stimulus condition. For the sham stimulation a specific sham-coil system was used. Fourteen patients were followed for 6 months. Treatment outcome was assessed with a specific tinnitus questionnaire (Goebel and Hiller). Tertiary referral medical center. Increased metabolic activation in the auditory cortex was verified in all patients. After 5 days of verum rTMS, a highly significant improvement of the tinnitus score was found whereas the sham treatment did not show any significant changes. The treatment outcome after 6 months still demonstrated significant reduction of tinnitus score. These preliminary results demonstrate that neuronavigated rTMS offers new possibilities in the understanding and treatment of chronic tinnitus.

  20. Effects of high-frequency repetitive transcranial magnetic stimulation of primary motor cortex on laser-evoked potentials in migraine.

    PubMed

    de Tommaso, Marina; Brighina, Filippo; Fierro, Brigida; Francesco, Vito Devito; Santostasi, Roberto; Sciruicchio, Vittorio; Vecchio, Eleonora; Serpino, Claudia; Lamberti, Paolo; Livrea, Paolo

    2010-12-01

    The aim of this study was to examine the effects of high-frequency (HF) repetitive transcranial magnetic stimulation (rTMS) of the left primary motor cortex (M1) on subjective pain and evoked responses induced by laser stimulation (LEPs) of the contralateral hand and supraorbital zone in a cohort of migraine patients without aura during the inter-critical phase, and to compare the effects with those of non-migraine healthy controls. Thirteen migraine patients and 12 sex- and age-matched controls were evaluated. Each rTMS session consisted of 1,800 stimuli at a frequency of 5 Hz and 90% motor threshold intensity. Sham (control) rTMS was performed at the same stimulation position. The vertex LEP amplitude was reduced at the trigeminal and hand levels in the sham-placebo condition and after rTMS to a greater extent in the migraine patients than in healthy controls, while the laser pain rating was unaffected. These results suggest that HF rTMS of motor cortex and the sham procedure can both modulate pain-related evoked responses in migraine patients.

  1. Bilateral Repetitive Transcranial Magnetic Stimulation Combined with Intensive Swallowing Rehabilitation for Chronic Stroke Dysphagia: A Case Series Study

    PubMed Central

    Momosaki, Ryo; Abo, Masahiro; Kakuda, Wataru

    2014-01-01

    The purpose of this study was to clarify the safety and feasibility of a 6-day protocol of bilateral repetitive transcranial magnetic stimulation (rTMS) combined with intensive swallowing rehabilitation for chronic poststroke dysphagia. In-hospital treatment was provided to 4 poststroke patients (age at treatment: 56–80 years; interval between onset of stroke and treatment: 24–37 months) with dysphagia. Over 6 consecutive days, each patient received 10 sessions of rTMS at 3 Hz applied to the pharyngeal motor cortex bilaterally, followed by 20 min of intensive swallowing rehabilitation exercise. The swallowing function was evaluated by the Penetration Aspiration Scale (PAS), Modified Mann Assessment of Swallowing Ability (MMASA), Functional Oral Intake Scale (FOIS), laryngeal elevation delay time (LEDT) and Repetitive Saliva-Swallowing Test (RSST) on admission and at discharge. All patients completed the 6-day treatment protocol and none showed any adverse reactions throughout the treatment. The combination treatment improved laryngeal elevation delay time in all patients. Our proposed protocol of rTMS plus swallowing rehabilitation exercise seems to be safe and feasible for chronic stroke dysphagia, although its efficacy needs to be confirmed in a large number of patients. PMID:24803904

  2. Therapeutic effect of repetitive magnetic stimulation combined with speech and language therapy in post-stroke non-fluent aphasia.

    PubMed

    Yoon, Tae Hee; Han, Soo Jeong; Yoon, Tae Sik; Kim, Joo Sup; Yi, Tae Im

    2015-01-01

    To investigate the therapeutic effect of repetitive transcranial magnetic stimulation (rTMS) and speech and language therapy (SLT) on the improvement of performance on the Korean-version of the Western Aphasia Battery (K-WAB) in post-stroke non-fluent aphasic patients. Twenty post-stroke, non-fluent aphasic patients were enrolled and assigned to one of two groups: a case group (n = 10) or a control group (n = 10). Participants were recruited from the inpatient clinic of the Physical and Rehabilitation Medicine Department of Bundang Jesaeng General Hospital from March 2011 to January 2012. The case group received rTMS and SLT and the control group received SLT; both groups received these therapies for four weeks. Language functioning was evaluated using K-WAB before and after treatment. There were no significant differences between the groups' baseline characteristics and initial values (p > 0.05). After four weeks of therapy, there were significant improvements in repetition and naming in the case group (p < 0.05). However, there was no significant improvement in the control group (p > 0.05). rTMS combined with SLT can be an effective therapeutic method for treating aphasia in post-stroke non-fluent aphasic patients, although additional controlled and more systemic studies should be conducted.

  3. Subgenual Cingulate Theta Activity Predicts Treatment Response of Repetitive Transcranial Magnetic Stimulation in Participants With Vascular Depression

    PubMed Central

    Narushima, Kenji; McCormick, Laurie; Yamada, Throu; Thatcher, Robert; Robinson, Robert G.

    2013-01-01

    Repetitive transcranial magnetic stimulation (rTMS) is an effective treatment for depression. Increased metabolism in the anterior cingulate cortex (ACC) is a known predictor for antidepressant response. The authors assessed whether increased theta power within the ACC predicts rTMS response in participants with vascular depression. Sixty-five participants were randomized to active or sham rTMS. Outcome was assessed using the Hamilton Depression Rating Scale. Electroencephalography was obtained, and comparisons were made among each group with a normative database using low-resolution electromagnetic tomography. Results suggest that vascular depression participants respond well to rTMS and that increased low-theta power in the subgenual ACC predicts response to rTMS. PMID:20160213

  4. Repetitive Transcranial Magnetic Stimulation (rTMS) Modulates Event-Related Potential (ERP) Indices of Attention in Autism

    PubMed Central

    Casanova, Manuel F.; Baruth, Joshua M.; El-Baz, Ayman; Tasman, Allan; Sears, Lonnie; Sokhadze, Estate

    2014-01-01

    Individuals with autism spectrum disorder (ASD) have previously been shown to have significantly augmented and prolonged event-related potentials (ERP) to irrelevant visual stimuli compared to controls at both early and later stages (e.g., N200, P300) of visual processing and evidence of an overall lack of stimulus discrimination. Abnormally large and indiscriminative cortical responses to sensory stimuli may reflect cortical inhibitory deficits and a disruption in the excitation/inhibition ratio. Low-frequency (≤1HZ) repetitive transcranial magnetic stimulation (rTMS) has been shown to increase inhibition of stimulated cortex by the activation of inhibitory circuits. It was our prediction that after 12 sessions of low-frequency rTMS applied bilaterally to the dorsolateral prefrontal cortices in individuals with ASD there would be a significant improvement in ERP indices of selective attention evoked at later (i.e., 200–600 ms) stages of attentional processing as well as an improvement in motor response error rate. We assessed 25 participants with ASD in a task of selective attention using illusory figures before and after 12 sessions of rTMS in a controlled design where a waiting-list group of 20 children with ASD performed the same task twice. We found a significant improvement in both N200 and P300 components as a result of rTMS as well as a significant reduction in response errors. We also found significant reductions in both repetitive behavior and irritability according to clinical behavioral questionnaires as a result of rTMS. We propose that rTMS has the potential to become an important therapeutic tool in ASD research and treatment. PMID:24683490

  5. Cognitive correlates of repetitive transcranial magnetic stimulation (rTMS) in treatment-resistant depression- a pilot study

    PubMed Central

    2012-01-01

    Background The aim of the current study was to investigate the cognitive correlates of repetitive transcranial magnetic stimulation (rTMS) in 10 treatment-resistant depression patients. Methods Patients received forty 20-min sessions of fast-frequency (10 Hz) rTMS of the left dorsolateral prefrontal cortex (DLPFC) over 20 days. Concept-shift ability (accuracy and duration of performance) was assessed daily with a Modified Concept-Shifting Task (mCST) in patients and in eight healthy volunteers. General cognitive functioning test (Repeatable Battery for the Assessment of Neuropsychological Status; RBANS), Beck Depression Inventory (BDI) and Hamilton Depression Rating Scale (HAM-D) were applied before the first and after the last rTMS. Results Compared to before rTMS on the first 10 days, the patients performed the mCST significantly more accurately after rTMS on the last 10 days (p < .001, partial eta squared=.78) while the same comparison in healthy volunteers was not statistically significant (p = .256, partial eta squared=.18). A significant improvement in immediate memory on RBANS and reduction in BDI and HAM-D scores were also observed after the last compared to before the first rTMS. Conclusion The rTMS is associated with an improvement in selective cognitive functions that is not explained by practice effects on tasks administered repeatedly. Trial registration Name: "Repetitive Transcranial Magnetic Stimulation (rTMS) in the treatment of depression, assessed with HAM-D over a four week period." URL: www.actr.org.au Registration number: ACTRN012605000145606 PMID:23031294

  6. [The expression of substance P in airway mucosa of guinea pigs with repetitive esophageal stimulation by hydrochloric acid].

    PubMed

    Li, Qin-zi; Kong, Ling-fei; Zhang, Shu-na; Zhong, Zhao-shuang; Zhang, Bao-hui; Liu, Xiao-feng

    2009-06-01

    To observe the expression of substance P (SP) in the airway mucosa of guinea pigs with repetitive esophageal stimulation by hydrochloric acid (HCL). Twenty adult guinea pigs were randomly divided into 2 groups (n = 10 each): (1) The HCL model group: On the day of experimentation, guinea pigs were maintained under ketamine anesthesia. A 5F catheter was inserted orally into the lumen of the middle and lower esophagus. The esophagus of each animal was perfused with HCl-P for 20 min/d for 14 d. (2) The PBS control group: The esophagus of each animal was perfused with PBS instead. The bronchial responsiveness to Ach given intravenously with increasing doses (3.125, 6.25, 12.5, 25, 50, 100 microg/kg) was measured after the last perfusion. The left lung was isolated for pathological examination. Lung sections were stained with hematoxylin and eosin, and other sections were prepared for immunohistochemistry using monoclonal antibodies against SP. In response to increasing doses of ACh, all guinea pigs showed dose-dependent increases in R(L). However, when the dose of ACh was increased to 25 microg/kg, the airway responsiveness increased significantly in the HCl-P model animals compared with the PBS control group (t values = 43.057, 51.410, 57.359 respectively, all P<0.01). The mean gray values of SP decreased significantly in the tracheal epithelia and the distal airway walls of the model group compared with the PBS control group (t values = 3.44, 2.16 respectively, all P<0.01). There was airway neurogenic inflammation in guinea pigs with repetitive esophageal stimulation by HCL, which maybe closely related to the pathogenesis of gastro-esophageal reflux disease.

  7. Low frequency repetitive transcranial magnetic stimulation targeted to PMC followed by M1 modulates excitability differently from PMC or M1 stimulation alone

    PubMed Central

    Chen, Mo; Deng, Huiqiong; Schmidt, Rebekah L.; Kimberley, Teresa J.

    2016-01-01

    Objectives The excitability of primary motor cortex (M1) can be modulated by applying low-frequency repetitive transcranial magnetic stimulation (rTMS) over M1 or premotor cortex (PMC). A comparison of inhibitory effect between the two locations has been reported with inconsistent results. This study compared the response secondary to rTMS applied over M1, PMC and a combined PMC+M1 stimulation approach which first targets stimulation over PMC then M1. Materials and Methods Ten healthy participants were recruited for a randomized, cross-over design with a 1-week wash-out between visits. Each visit consisted of a pre-test, an rTMS intervention and a post-test. Outcome measures included short interval intracortical inhibition (SICI), intracortical facilitation (ICF) and cortical silent period (CSP). Participants received one of the three interventions in random order at each visit including: 1-Hz rTMS at 90% of resting motor threshold to: M1 (1200 pulses), PMC (1200 pulses) and PMC+M1 (600 pulses each, 1200 total). Results PMC+M1 stimulation resulted in significantly greater inhibition than the other locations for ICF (P = 0.005) and CSP (P < 0.001); for SICI, increased inhibition (group effect) was not observed after any of the three interventions and there was no significant difference between the three interventions. Conclusion The results indicate that PMC+M1 stimulation may modulate brain excitability differently from PMC or M1 alone. CSP was the assessment measure most sensitive to changes in inhibition and was able to distinguish between different inhibitory protocols. This work presents a novel procedure that may have positive implications for therapeutic interventions. PMID:26307511

  8. Placebo Controlled Study of Repetitive Transcranial Magnetic Stimulation for the Treatment of Parkinson’s Disease

    DTIC Science & Technology

    2004-03-01

    References Aarsland D., Larsen J.P., Waage 0., Langeveld J.H. Maintenance electroconvulsive therapy for Parkinson’s disease. Convuls Ther. 1997; 13: 274-277...following electroconvulsive therapy . 1: Psychopharmacology (Berl). 1982; 76: 371-376. Belmaker R.H., Grisaru N. Magnetic stimulation of the brain in...rTMS might have any long-lasting therapeutic effects (weeks or months) in persons with PD who are already receiving optimal available therapy

  9. Supercontinuum Stimulated Emission Depletion Fluorescence Lifetime Imaging

    SciTech Connect

    Lesoine, Michael; Bose, Sayantan; Petrich, Jacob; Smith, Emily

    2012-06-13

    Supercontinuum (SC) stimulated emission depletion (STED) fluorescence lifetime imaging is demonstrated by using time-correlated single-photon counting (TCSPC) detection. The spatial resolution of the developed STED instrument was measured by imaging monodispersed 40-nm fluorescent beads and then determining their fwhm, and was 36 ± 9 and 40 ± 10 nm in the X and Y coordinates, respectively. The same beads measured by confocal microscopy were 450 ± 50 and 430 ± 30 nm, which is larger than the diffraction limit of light due to underfilling the microscope objective. Underfilling the objective and time gating the signal were necessary to achieve the stated STED spatial resolution. The same fluorescence lifetime (2.0 ± 0.1 ns) was measured for the fluorescent beads by using confocal or STED lifetime imaging. The instrument has been applied to study Alexa Fluor 594-phalloidin labeled F-actin-rich projections with dimensions smaller than the diffraction limit of light in cultured cells. Fluorescence lifetimes of the actin-rich projections range from 2.2 to 2.9 ns as measured by STED lifetime imaging.

  10. High-Frequency Repetitive Transcranial Magnetic Stimulation Effects on Motor Intracortical Neurophysiology: A Sham-Controlled Investigation.

    PubMed

    Malcolm, Matt P; Paxton, Roger J

    2015-10-01

    The purpose of this study was to investigate the effects of high-frequency repetitive transcranial magnetic stimulation (rTMS) versus sham stimulation on intracortical inhibition (ICI) and intracortical facilitation within the motor cortex. Such data are needed to better understand the presumed neurophysiologic effects of rTMS. The authors hypothesized that, compared with sham stimulation, 20 Hz rTMS will decrease ICI and increase intracortical facilitation in healthy volunteers. Using single-pulse and paired-pulse TMS, the authors evaluated prestimulation and poststimulation effects on motor cortex neurophysiology in neurologically healthy volunteers who received 2,000 stimuli of either 20 Hz rTMS (n = 11) or sham rTMS (n = 8). Primary outcomes were changes in ICI and intracortical facilitation and secondary outcomes were changes in motor threshold and motor evoked potential amplitude, and both were assessed using separate 2 × 2 (group × time) repeated-measures analysis of variance. For ICI, there were main effects of time (P = 0.002) and group (P < 0.001) with a significant group-by-time interaction (P < 0.01). Intracortical inhibition decreased after rTMS, but was unchanged by sham rTMS. Intracortical facilitation results revealed a main effect of group (P = 0.02) and a significant group-by-time interaction (P = 0.048). Intracortical facilitation increased after rTMS and was slightly reduced after sham rTMS. The group-by-time interactions for motor threshold and motor evoked potential amplitude were not significant. High-frequency rTMS significantly influences the excitatory and inhibitory outputs of motor intracortical networks, specifically increasing intracortical facilitation and reducing ICI as compared with sham stimulation. Such changes were observed despite no significant changes in broader measures of motor cortex activation, that is, motor threshold and motor evoked potential amplitude.

  11. Cumulative sessions of repetitive transcranial magnetic stimulation (rTMS) build up facilitation to subsequent TMS-mediated behavioural disruptions.

    PubMed

    Valero-Cabré, Antoni; Pascual-Leone, Alvaro; Rushmore, Richard J

    2008-02-01

    A single session of repetitive transcranial magnetic stimulation (rTMS) can induce behavioural effects that outlast the duration of the stimulation train itself (off-line effects). Series of rTMS sessions on consecutive days are being used for therapeutic applications in a variety of disorders and are assumed to lead to the build-up of cumulative effects. However, no studies have carefully assessed this notion. In the present study we applied 30 daily sessions of 1 Hz rTMS (continuous train of 20 min) to repeatedly modulate activity in the posterior parietal cortex and associated neural systems in two intact cats. We assessed the effect on visuospatial orientation before and after each stimulation session. Cumulative sessions of rTMS progressively induced visuospatial neglect-like 'after-effects' of greater magnitude (from 5-10% to 40-50% error levels) and increasing spatial extent (from 90-75 degrees to 45-30 degrees eccentricity locations), affecting the visual hemifield contralateral to the stimulated hemisphere. Nonetheless, 60 min after each TMS session, visual detection-localization abilities repeatedly returned to baseline levels. Furthermore, no lasting behavioural effect could be demonstrated at any time across the study, when subjects were tested 1 or 24 h post-rTMS. We conclude that the past history of periodically cumulative rTMS sessions builds up a lasting 'memory', resulting in increased facilitation to subsequent TMS-induced disruptions. Such a phenomenon allows a behavioural effect of progressively higher magnitude, but equal duration, in response to individual TMS interventions.

  12. Results on the spatial resolution of repetitive transcranial magnetic stimulation for cortical language mapping during object naming in healthy subjects.

    PubMed

    Sollmann, Nico; Hauck, Theresa; Tussis, Lorena; Ille, Sebastian; Maurer, Stefanie; Boeckh-Behrens, Tobias; Ringel, Florian; Meyer, Bernhard; Krieg, Sandro M

    2016-10-24

    The spatial resolution of repetitive navigated transcranial magnetic stimulation (rTMS) for language mapping is largely unknown. Thus, to determine a minimum spatial resolution of rTMS for language mapping, we evaluated the mapping sessions derived from 19 healthy volunteers for cortical hotspots of no-response errors. Then, the distances between hotspots (stimulation points with a high error rate) and adjacent mapping points (stimulation points with low error rates) were evaluated. Mean distance values of 13.8 ± 6.4 mm (from hotspots to ventral points, range 0.7-30.7 mm), 10.8 ± 4.8 mm (from hotspots to dorsal points, range 2.0-26.5 mm), 16.6 ± 4.8 mm (from hotspots to apical points, range 0.9-27.5 mm), and 13.8 ± 4.3 mm (from hotspots to caudal points, range 2.0-24.2 mm) were measured. According to the results, the minimum spatial resolution of rTMS should principally allow for the identification of a particular gyrus, and according to the literature, it is in good accordance with the spatial resolution of direct cortical stimulation (DCS). Since measurement was performed between hotspots and adjacent mapping points and not on a finer-grained basis, we only refer to a minimum spatial resolution. Furthermore, refinement of our results within the scope of a prospective study combining rTMS and DCS for resolution measurement during language mapping should be the next step.

  13. Effects of Low Frequency Prefrontal Repetitive Transcranial Magnetic Stimulation on the N2 Amplitude in a GoNogo Task

    PubMed Central

    Grossheinrich, Nicola; Reinl, Maren; Pogarell, Oliver; Karch, Susanne; Mulert, Christoph; Brueckl, Monika; Hennig-Fast, Kristina; Rau, Anne; Epple, Maria; Hornig, Ariane; Padberg, Frank

    2013-01-01

    During the last decade, repetitive transcranial magnetic stimulation (rTMS) of the prefrontal cortex has become established as a treatment for various mental diseases. The rational of prefrontal stimulation has been adapted from the mode of action known from rTMS using motor-evoked potentials though little is known about the precise effect of rTMS at prefrontal sites. The objective of the current study is to investigate the inhibitory effect of prefrontal 1 Hz rTMS by stimulating the generators of event-related potentials (ERP) which are located in the prefrontal cortex. Thus, 1 Hz rTMS was applied offline over the left dorsolateral prefrontal cortex (DLPFC) and the medial prefrontal cortex (MPFC) in 18 healthy subjects who subsequently underwent a GoNogo task. Both active conditions were compared to sham rTMS within a randomized and counterbalanced cross-over design in one day. ERPs were recorded during task performance and the N2 and the P3 were analysed. After 1 Hz rTMS of the left DLPFC (but not of the MPFC), an inhibitory effect on the N2 amplitude was observed, which was related to inhibitory control. In contrast, after 1 Hz rTMS of the MPFC (but not at the left DLPFC) a trend towards an increased P3 amplitude was found. There was no significant modulation of latencies and behavioural data. The results argue in favour of an inhibitory effect of 1 Hz rTMS on N2 amplitudes in a GoNogo task. Our findings suggest that rTMS may mildly modulate prefrontally generated ERP immediately after stimulation, even where behavioural effects are not measurable. Thus, combined rTMS-ERP approaches need to be further established in order to serve as paradigms in experimental neuroscience and clinical research. PMID:23826214

  14. Design of laser beam expander in underwater high-repetition-rate range-gated imaging system

    NASA Astrophysics Data System (ADS)

    Zhong, Wei; Zhang, Xiaohui

    2015-10-01

    Active underwater imaging systems, using an artificial light source for underwater target illumination, have preferable practical value in military and civil domain. Back-scattering of water impacts imaging system performance by reducing image contrast, and this is especially bad when the light source is close to the camera. Range-gated technique can effectively rejecting the back-scattering of water and improve the range of underwater target detection, while it can only collect image at certain distance for every laser impulse. High-repetition-rate green laser is a better light source in underwater range-gated imaging system. It has smaller pulse energy, while it can improve the imaging result. In order to illuminate the proper area underwater according to the different distance between the laser source and targets, there must be a magnifying-ratio variable beam expander to adjust the divergent angle of the laser. Challenges associated with magnifying-ratio computation and designing of beam expander are difficult to overcome due to the obvious refraction and forward-scattering of water. An efficiency computing method is presented to obtain the magnifying-ratio of beam expander. The illuminating area of laser beam can be computed according to the refraction index and beam spread function (BSF) which has already considered forward-scattering process. The magnifying-ratio range of beam expander should be 0.925~3.09 in order to obtain about φ1m illuminating area when the distance between laser and target is 10~40m. A magnifying-ratio variable beam expander is designed according to computation. Underwater experiments show that this beam expander plays an effective role on illuminating in underwater high-repetition-rate range-rated Imaging system.

  15. MEMS-based multiphoton endomicroscope for repetitive imaging of mouse colon

    PubMed Central

    Duan, Xiyu; Li, Haijun; Qiu, Zhen; Joshi, Bishnu P.; Pant, Asha; Smith, Arlene; Kurabayashi, Katsuo; Oldham, Kenn R.; Wang, Thomas D.

    2015-01-01

    We demonstrate a handheld multiphoton endomicroscope with 3.4 mm distal diameter that can repetitively image mouse colon in vivo. A 2D resonant MEMS mirror was developed to perform beam scanning in a Lissajous pattern. The instrument has an effective numerical aperture of 0.63, lateral and axial resolution of 2.03 and 9.02 μm, respectively, working distance of 60 μm, and image field-of-view of 300 × 300 μm2. Hoechst was injected intravenously in mice to stain cell nuclei. We were able to collect histology-like images in vivo at 5 frames/sec, and distinguish between normal and pre-malignant colonic epithelium. PMID:26309768

  16. Can neurophysiologic measures serve as biomarkers for the efficacy of repetitive transcranial magnetic stimulation treatment of major depressive disorder?

    PubMed

    Kobayashi, Brian; Cook, Ian A; Hunter, Aimee M; Minzenberg, Michael J; Krantz, David E; Leuchter, Andrew F

    2017-03-31

    Repetitive transcranial magnetic stimulation (rTMS) is an effective treatment for Major Depressive Disorder (MDD). There are clinical data that support the efficacy of many different approaches to rTMS treatment, and it remains unclear what combination of stimulation parameters is optimal to relieve depressive symptoms. Because of the costs and complexity of studies that would be necessary to explore and compare the large number of combinations of rTMS treatment parameters, it would be useful to establish reliable surrogate biomarkers of treatment efficacy that could be used to compare different approaches to treatment. This study reviews the evidence that neurophysiologic measures of cortical excitability could be used as biomarkers for screening different rTMS treatment paradigms. It examines evidence that: (1) changes in excitability are related to the mechanism of action of rTMS; (2) rTMS has consistent effects on measures of excitability that could constitute reliable biomarkers; and (3) changes in excitability are related to the outcomes of rTMS treatment of MDD. An increasing body of evidence indicates that these neurophysiologic measures have the potential to serve as reliable biomarkers for screening different approaches to rTMS treatment of MDD.

  17. Abnormal plasticity of the sensorimotor cortex to slow repetitive transcranial magnetic stimulation in patients with writer's cramp.

    PubMed

    Bäumer, Tobias; Demiralay, Cüneyt; Hidding, Ute; Bikmullina, Rosalia; Helmich, Rick C; Wunderlich, Silke; Rothwell, John; Liepert, Joachim; Siebner, Hartwig R; Münchau, Alexander

    2007-01-01

    Previous studies demonstrated functional abnormalities in the somatosensory system, including a distorted functional organization of the somatosensory cortex (S1) in patients with writer's cramp. We tested the hypothesis that these functional alterations render S1 of these patients more susceptible to the "inhibitory" effects of subthreshold 1 Hz repetitive transcranial magnetic stimulation (rTMS) given to S1. Seven patients with writer's cramp and eight healthy subjects were studied. Patients also received rTMS to the motor cortex hand area (M1). As an outcome measure, short-latency afferent inhibition (SAI) was tested. SAI was studied in the relaxed first dorsal interosseous muscle using conditioning electrical stimulation of the index finger and TMS pulses over the contralateral M1. Baseline SAI did not differ between groups. S1 but not M1 rTMS reduced SAI in patients. rTMS had no effects on SAI in healthy subjects. Because SAI is mediated predominantly at a cortical level in the sensorimotor cortex, we conclude that there is an abnormal responsiveness of this area to 1 Hz rTMS in writer's cramp, which may represent a trait toward maladaptive plasticity in the sensorimotor system in these patients.

  18. Repetitive transcranial magnetic stimulation for generalised anxiety disorder: a pilot randomised, double-blind, sham-controlled trial.

    PubMed

    Diefenbach, Gretchen J; Bragdon, Laura B; Zertuche, Luis; Hyatt, Christopher J; Hallion, Lauren S; Tolin, David F; Goethe, John W; Assaf, Michal

    2016-09-01

    Repetitive transcranial magnetic stimulation (rTMS) holds promise for treating generalised anxiety disorder (GAD) but has only been studied in uncontrolled research. This is the first randomised controlled trial (clinicaltrials.gov: NCT01659736) to investigate the efficacy and neural correlates of rTMS in GAD. Twenty five participants (active n = 13; sham, n = 12) enrolled. rTMS was targeted at the right dorsolateral prefrontal cortex (DLPFC, 1 Hz, 90% resting motor threshold). Response and remission rates were higher in the active v. sham groups and there were significant group × time interactions for anxiety, worry and depressive symptoms, favouring active v. sham. In addition, right DLPFC activation during a decision-making gambling task increased at post-treatment for active rTMS only, and changes in neuroactivation correlated significantly with changes in worry symptoms. Findings provide preliminary evidence that rTMS may improve GAD symptoms in association with modifying neural activity in the stimulation site. © The Royal College of Psychiatrists 2016.

  19. Effects of 1-Hz repetitive transcranial magnetic stimulation on long-latency reflexes and cortical relay time.

    PubMed

    Tataroglu, Cengiz; Sair, Ahmet; Parlaz, Ahu; Deneri, Ersin

    2011-06-01

    Long-latency reflexes (LLRs) of hand muscles include a transcortical component. Cortical relay time estimated by the subtraction of motor and somatosensory evoked potentials from LLR reflects the physiology of the central neural pathway of LLR. It is believed that 1-Hz repetitive transcranial magnetic stimulation (rTMS) of the primary motor cortex can decrease cortical excitability for approximately 15 minutes at intracortical level. The aim of the study was to analyze LLR and cortical relay time before and after 1-Hz rTMS. Long-latency reflex and H reflex obtained from the thenar muscles by electrical stimulation of the median nerve of 16 healthy subjects. Additionally, motor evoked potentials and somatosensory evoked potentials were also recorded. Cortical relay time was calculated by the subtraction of motor evoked potential and somatosensory evoked potential latencies from LLR. These electrophysiologic recordings were performed before and after 15 minutes of 1-Hz rTMS over the motor area for the thenar muscles in the primary motor cortex. The amplitudes of LLR and motor evoked potential were significantly decreased after rTMS, but the H reflex of the thenar muscle and somatosensory evoked potentials were unchanged. The major finding of our study was a shortened duration of cortical relay time after rTMS. In conclusion, our findings suggest that the LLR of the thenar muscles has a transcortical pathway and cortical relay time that can give some information about the physiology of the intracortical pathway of LLR.

  20. Efficacy of repetitive transcranial magnetic stimulation with quetiapine in treating bipolar II depression: a randomized, double-blinded, control study

    PubMed Central

    Hu, Shao-hua; Lai, Jian-bo; Xu, Dong-rong; Qi, Hong-li; Peterson, Bradley S.; Bao, Ai-min; Hu, Chan-chan; Huang, Man-li; Chen, Jing-kai; Wei, Ning; Hu, Jian-bo; Li, Shu-lan; Zhou, Wei-hua; Xu, Wei-juan; Xu, Yi

    2016-01-01

    The clinical and cognitive responses to repetitive transcranial magnetic stimulation (rTMS) in bipolar II depressed patients remain unclear. In this study, thirty-eight bipolar II depressed patients were randomly assigned into three groups: (i) left high-frequency (n = 12), (ii) right low-frequency (n = 13), (iii) sham stimulation (n = 13), and underwent four-week rTMS with quetiapine concomitantly. Clinical efficacy was evaluated at baseline and weekly intervals using the 17-item Hamilton Depression Rating Scale (HDRS-17) and Montgomery-Asberg Depression Rating Scale (MADRS). Cognitive functioning was assessed before and after the study with the Wisconsin Card Sorting Test (WCST), Stroop Word-Color Interference Test (Stroop), and Trail Making Test (TMT). Thirty-five patients were included in the final analysis. Overall, the mean scores of both the HDRS-17 and the MADRS significantly decreased over the 4-week trial, which did not differ among the three groups. Exploratory analyses revealed no differences in factor scores of HDRS-17s, or in response or remission rates. Scores of WCST, Stroop, or TMT did not differ across the three groups. These findings indicated active rTMS combined with quetiapine was not superior to quetiapine monotherapy in improving depressive symptoms or cognitive performance in patients with bipolar II depression. PMID:27460201

  1. Repetitive transcranial magnetic stimulation for stroke rehabilitation-potential therapy or misplaced hope?

    PubMed

    Bates, Kristyn Alissa; Rodger, Jennifer

    2015-01-01

    Repeated sessions of transcranial magnetic stimulation (rTMS) are capable of changing and modulating neural activity beyond the period of stimulation. Because many neurological disorders are thought to involve abnormal or dysfunctional neuronal activity, it is hypothesised that the therapeutic action of rTMS may occur through modulating and reversing abnormal activity and facilitating neuroplasticity.Numerous clinical studies have investigated the safety and efficacy of rTMS treatment for a wide variety of conditions including depression, anxiety disorders including obsessive compulsive disorder, Parkinson's disease, stroke, tinnitus, affective disorders, schizophrenia and chronic pain. Despite some promising results, rTMS is not currently widely used to assist in recovery from neurotrama. In this review, we argue that the therapeutic promise of rTMS is limited because the mechanisms of action of rTMS are not completely understood and therefore it is difficult to determine which treatment protocols are appropriate for specific neurological conditions. We use the application of rTMS in motor functional recovery from cerebral ischemic stroke to illustrate the difficulties in interpreting and assessing the therapeutic potential of rTMS for neurotrauma in terms of the presumed mechanisms of action of rTMS. Future directions for research will also be discussed.

  2. Low-Frequency Repetitive Transcranial Magnetic Stimulation and Intensive Occupational Therapy for Poststroke Patients with Upper Limb Hemiparesis: Preliminary Study of a 15-Day Protocol

    ERIC Educational Resources Information Center

    Kakuda, Wataru; Abo, Masahiro; Kobayashi, Kazushige; Momosaki, Ryo; Yokoi, Aki; Fukuda, Akiko; Ishikawa, Atsushi; Ito, Hiroshi; Tominaga, Ayumi

    2010-01-01

    The purpose of the study was to determine the safety and feasibility of a 15-day protocol of low-frequency repetitive transcranial magnetic stimulation (rTMS) combined with intensive occupational therapy (OT) on motor function and spasticity in hemiparetic upper limbs in poststroke patients. Fifteen poststroke patients (age at study entry 55 [plus…

  3. Low-Frequency Repetitive Transcranial Magnetic Stimulation and Intensive Occupational Therapy for Poststroke Patients with Upper Limb Hemiparesis: Preliminary Study of a 15-Day Protocol

    ERIC Educational Resources Information Center

    Kakuda, Wataru; Abo, Masahiro; Kobayashi, Kazushige; Momosaki, Ryo; Yokoi, Aki; Fukuda, Akiko; Ishikawa, Atsushi; Ito, Hiroshi; Tominaga, Ayumi

    2010-01-01

    The purpose of the study was to determine the safety and feasibility of a 15-day protocol of low-frequency repetitive transcranial magnetic stimulation (rTMS) combined with intensive occupational therapy (OT) on motor function and spasticity in hemiparetic upper limbs in poststroke patients. Fifteen poststroke patients (age at study entry 55 [plus…

  4. Metabolic changes of cerebrum by repetitive transcranial magnetic stimulation over lateral cerebellum: a study with FDG PET.

    PubMed

    Cho, Sang Soo; Yoon, Eun Jin; Bang, Sung Ae; Park, Hyun Soo; Kim, Yu Kyeong; Strafella, Antonio P; Kim, Sang Eun

    2012-09-01

    To better understand the functional role of cerebellum within the large-scale cerebellocerebral neural network, we investigated the changes of neuronal activity elicited by cerebellar repetitive transcranial magnetic stimulation (rTMS) using (18)F-fluorodeoxyglucose (FDG) and positron emission tomography (PET). Twelve right-handed healthy volunteers were studied with brain FDG PET under two conditions: active rTMS of 1 Hz frequency over the left lateral cerebellum and sham stimulation. Compared to the sham condition, active rTMS induced decreased glucose metabolism in the stimulated left lateral cerebellum, the areas known to be involved in voluntary motor movement (supplementary motor area and posterior parietal cortex) in the right cerebral hemisphere, and the areas known to be involved in cognition and emotion (orbitofrontal, medial frontal, and anterior cingulate gyri) in the left cerebral hemisphere. Increased metabolism was found in cognition- and language-related brain regions such as the left inferior frontal gyrus including Broca's area, bilateral superior temporal gyri including Wernicke's area, and bilateral middle temporal gyri. Left cerebellar rTMS also led to increased metabolism in the left cerebellar dentate nucleus and pons. These results demonstrate that rTMS over the left lateral cerebellum modulates not only the target region excitability but also excitability of remote, but interconnected, motor-, language-, cognition-, and emotion-related cerebral regions. They provide further evidence that the cerebellum is involved not only in motor-related functions but also in higher cognitive abilities and emotion through the large-scale cerebellocereberal neural network.

  5. A proof-of-concept study on the combination of repetitive transcranial magnetic stimulation and relaxation techniques in chronic tinnitus.

    PubMed

    Kreuzer, Peter M; Poeppl, Timm B; Bulla, Jan; Schlee, Winfried; Lehner, Astrid; Langguth, Berthold; Schecklmann, Martin

    2016-10-01

    Interference of ongoing neuronal activity and brain stimulation motivated this study to combine repetitive transcranial magnetic stimulation (rTMS) and relaxation techniques in tinnitus patients. Forty-two patients were enrolled in this one-arm proof-of-concept study to receive ten sessions of rTMS applied to the left dorsolateral prefrontal cortex and temporo-parietal cortex. During stimulation, patients listened to five different kinds of relaxation audios. Variables of interest were tinnitus questionnaires, tinnitus numeric rating scales, depressivity, and quality of life. Results were compared to results of historical control groups having received the same rTMS protocol (active control) and sham treatment (placebo) without relaxation techniques. Thirty-eight patients completed the treatment, drop-out rates and adverse events were low. Responder rates (reduction in tinnitus questionnaire (TQ) score ≥5 points 10 weeks after treatment) were 44.7 % in the study, 27.8 % in the active control group, and 21.7 % in the placebo group, differing between groups on a near significant level. For the tinnitus handicap inventory (THI), the main effect of group was not significant. However, linear mixed model analyses showed that the relaxation/rTMS group differed significantly from the active control group showing steeper negative THI trend for the relaxation/rTMS group indicating better amelioration over the course of the trial. Deepness of relaxation during rTMS and selection of active relaxation vs. passive listening to music predicted larger TQ. All remaining secondary outcomes turned out non-significant. This combined treatment proved to be a safe, feasible and promising approach to enhance rTMS treatment effects in chronic tinnitus.

  6. Carbonic Anhydrase I, II, and VI, Blood Plasma, Erythrocyte and Saliva Zinc and Copper Increase After Repetitive Transcranial Magnetic Stimulation

    PubMed Central

    Henkin, Robert I.; Potolicchio, Samuel J.; Levy, Lucien M.; Moharram, Ramy; Velicu, Irina; Martin, Brian M.

    2010-01-01

    Introduction Repetitive transcranial magnetic stimulation (rTMS) has been used to treat symptoms from many disorders; biochemical changes occurred with this treatment. Preliminary studies with rTMS in patients with taste and smell dysfunction improved sensory function and increased salivary carbonic anhydrase (CA) VI and erythrocyte CA I, II. To obtain more information about these changes after rTMS, we measured changes in several CA enzymes, proteins, and trace metals in their blood plasma, erythrocytes, and saliva. Methods Ninety-three patients with taste and smell dysfunction were studied before and after rTMS in an open clinical trial. Before and after rTMS, we measured erythrocyte CA I, II and salivary CA VI, zinc and copper in parotid saliva, blood plasma, and erythrocytes, and appearance of novel salivary proteins by using mass spectrometry. Results After rTMS, CA I, II and CA VI activity and zinc and copper in saliva, plasma, and erythrocytes increased with significant sensory benefit. Novel salivary proteins were induced at an m/z value of 21.5K with a repetitive pattern at intervals of 5K m/z. Conclusions rTMS induced biochemical changes in specific enzymatic activities, trace metal concentrations, and induction of novel salivary proteins, with sensory improvement in patients with taste and smell dysfunction. Because patients with several neurologic disorders exhibit taste and smell dysfunction, including Parkinson disease, Alzheimer disease, and multiple sclerosis, and because rTMS improved their clinical symptoms, the biochemical changes we observed may be relevant not only in our patients with taste and smell dysfunction but also in patients with neurologic disorders with these sensory abnormalities. PMID:20090508

  7. 200 ps FWHM and 100 MHz repetition rate ultrafast gated camera for optical medical functional imaging

    NASA Astrophysics Data System (ADS)

    Uhring, Wilfried; Poulet, Patrick; Hanselmann, Walter; Glazenborg, René; Zint, Virginie; Nouizi, Farouk; Dubois, Benoit; Hirschi, Werner

    2012-04-01

    The paper describes the realization of a complete optical imaging device to clinical applications like brain functional imaging by time-resolved, spectroscopic diffuse optical tomography. The entire instrument is assembled in a unique setup that includes a light source, an ultrafast time-gated intensified camera and all the electronic control units. The light source is composed of four near infrared laser diodes driven by a nanosecond electrical pulse generator working in a sequential mode at a repetition rate of 100 MHz. The resulting light pulses, at four wavelengths, are less than 80 ps FWHM. They are injected in a four-furcated optical fiber ended with a frontal light distributor to obtain a uniform illumination spot directed towards the head of the patient. Photons back-scattered by the subject are detected by the intensified CCD camera; there are resolved according to their time of flight inside the head. The very core of the intensified camera system is the image intensifier tube and its associated electrical pulse generator. The ultrafast generator produces 50 V pulses, at a repetition rate of 100 MHz and a width corresponding to the 200 ps requested gate. The photocathode and the Micro-Channel-Plate of the intensifier have been specially designed to enhance the electromagnetic wave propagation and reduce the power loss and heat that are prejudicial to the quality of the image. The whole instrumentation system is controlled by an FPGA based module. The timing of the light pulses and the photocathode gating is precisely adjustable with a step of 9 ps. All the acquisition parameters are configurable via software through an USB plug and the image data are transferred to a PC via an Ethernet link. The compactness of the device makes it a perfect device for bedside clinical applications.

  8. Magnetic resonance imaging of human mandibular elevator muscles after repetitive maximal clenching exercise.

    PubMed

    Gan, Y; Sasai, T; Nishiyama, H; Ma, X; Zhang, Z; Fuchihata, H

    2000-03-01

    Exercise can enhance the signal intensity (SI) of skeletal limb muscles on T2-weighted magnetic resonance imaging (MRI). The purpose here was to evaluate the effects of repetitive maximal clenching exercises involving the mandibular elevator muscles with T2-weighted MRI. Seven normal volunteers were imaged before and immediately after performing repetitive maximal clenching and at 3, 6, 9, 12, 15, 20 min after the exercise in a 1.5 T GE magnet with spin-echo sequences. SI in the masseter, medial pterygoid and temporalis increased significantly (p < 0.001) and the cross-sectional area (CSA) of masseter increased 10.11% on T2-weighted MRI after exercise. The increased SI and CSA declined approximately to the pre-exercise level in about 20 min after exercise. No SI and CSA changes were found in the inactive neck muscle and no SI changes in the mandibular bone marrow (p > 0.05). The findings suggest that the use of exercise-enhanced MRI might be helpful in the study of the function and dysfunction of muscles in the orofacial region.

  9. Myoplasmic free Mg2+ concentration during repetitive stimulation of single fibres from mouse skeletal muscle.

    PubMed Central

    Westerblad, H; Allen, D G

    1992-01-01

    1. The role of the myoplasmic free Mg2+ concentration ([Mg2+]i) in fatigue was studied in intact single fibres isolated from mouse skeletal muscle. Fatigue was produced by repeated tetanic stimulation. The fluorescent Mg2+ indicator furaptra was pressure injected into fibres. In vivo calibrations were performed to convert fluorescence signals into [Mg2+]i. 2. [Mg2+]i at rest was 0.78 +/- 0.05 mM (mean +/- S.E.M., n = 14). An increase of the extracellular [Mg2+] from 0.5 to 20 mM resulted in a small elevation of [Mg2+]i (86 microM in 5 min). Removal of extracellular Na+ did not affect [Mg2+]i. An intracellular alkanization of about 0.6 pH units gave a [Mg2+]i reduction of 65 microM. 3. During fatiguing stimulation [Mg2+]i initially remained almost constant and it then suddenly started to rise towards the end of the stimulation period. The onset of the [Mg2+]i rise was always followed by a rapid tension decline. In fatigue [Mg2+]i was approximately twice as high as at rest. 4. Fibres were injected with MgCl2 to study if the rise in [Mg2+]i could explain the tension decline in fatigue. An elevation of [Mg2+]i was accompanied by a tension reduction but the [Mg2+]i for a given tension was generally much higher in rested fibres injected with MgCl2 than in fatigued fibres. Thus the rise in [Mg2+]i as such cannot explain the tension reduction in fatigue. 5. Injection of MgCl2 was also used to assess the intracellular Mg2+ buffering. The mean Mg2+ buffer power (i.e. the ratio of the change in [Mg2+]i to the amount of Mg2+ added) was 0.62. 6. ATP is the quantitatively most important binding site for Mg2+ at rest and ATP breakdown is then a likely source of the [Mg2+]i increase in fatigue. The role of ATP breakdown in the increase of [Mg2+]i was studied with metabolic inhibition: fibres were exposed to iodoacetic acid to inhibit glycolysis and cyanide to inhibit oxidative phosphorylation. The pattern during metabolic inhibition was similar to that observed during fatigue

  10. Motion as motivation: using repetitive flexion movements to stimulate the approach system.

    PubMed

    Haeffel, Gerald J

    2011-12-01

    Research suggests that having a healthy approach system is critical for adaptive emotional functioning. The goal of the current study (n=186 undergraduates) was to determine the efficacy of an easy-to-disseminate and cost-efficient strategy for stimulating this system. The experiment tested the effects of repeated flexion movements (rFM) on approach system activation as measured by both self-report (BAS scales) and behavior. The results showed that rFM increased approach system motivation in men but not women. Men who completed the rFM task reported significantly greater levels of fun-seeking motivation than men in the control task. Moreover, the rFM task led to changes in actual behavior. Men who completed the rFM task exhibited significantly greater persistence on a difficult laboratory task than men in the control task. In contrast, women who completed the rFM task reported significantly lower levels of fun seeking and tended to exhibit less persistence on a difficult laboratory task than women in the control task. These results provide support for embodied theories of emotion as well as additional evidence for a gender difference in approach-avoidance tendencies.

  11. Spoken word memory traces within the human auditory cortex revealed by repetition priming and functional magnetic resonance imaging.

    PubMed

    Gagnepain, Pierre; Chételat, Gael; Landeau, Brigitte; Dayan, Jacques; Eustache, Francis; Lebreton, Karine

    2008-05-14

    Previous neuroimaging studies in the visual domain have shown that neurons along the perceptual processing pathway retain the physical properties of written words, faces, and objects. The aim of this study was to reveal the existence of similar neuronal properties within the human auditory cortex. Brain activity was measured using functional magnetic resonance imaging during a repetition priming paradigm, with words and pseudowords heard in an acoustically degraded format. Both the amplitude and peak latency of the hemodynamic response (HR) were assessed to determine the nature of the neuronal signature of spoken word priming. A statistically significant stimulus type by repetition interaction was found in various bilateral auditory cortical areas, demonstrating either HR suppression and enhancement for repeated spoken words and pseudowords, respectively, or word-specific repetition suppression without any significant effects for pseudowords. Repetition latency shift only occurred with word-specific repetition suppression in the right middle/posterior superior temporal sulcus. In this region, both repetition suppression and latency shift were related to behavioral priming. Our findings highlight for the first time the existence of long-term spoken word memory traces within the human auditory cortex. The timescale of auditory information integration and the neuronal mechanisms underlying priming both appear to differ according to the level of representations coded by neurons. Repetition may "sharpen" word-nonspecific representations coding short temporal variations, whereas a complex interaction between the activation strength and temporal integration of neuronal activity may occur in neuronal populations coding word-specific representations within longer temporal windows.

  12. Repetitive stimulation of autophagy-lysosome machinery by intermittent fasting preconditions the myocardium to ischemia-reperfusion injury.

    PubMed

    Godar, Rebecca J; Ma, Xiucui; Liu, Haiyan; Murphy, John T; Weinheimer, Carla J; Kovacs, Attila; Crosby, Seth D; Saftig, Paul; Diwan, Abhinav

    2015-01-01

    Autophagy, a lysosomal degradative pathway, is potently stimulated in the myocardium by fasting and is essential for maintaining cardiac function during prolonged starvation. We tested the hypothesis that intermittent fasting protects against myocardial ischemia-reperfusion injury via transcriptional stimulation of the autophagy-lysosome machinery. Adult C57BL/6 mice subjected to 24-h periods of fasting, every other day, for 6 wk were protected from in-vivo ischemia-reperfusion injury on a fed day, with marked reduction in infarct size in both sexes as compared with nonfasted controls. This protection was lost in mice heterozygous null for Lamp2 (coding for lysosomal-associated membrane protein 2), which demonstrate impaired autophagy in response to fasting with accumulation of autophagosomes and SQSTM1, an autophagy substrate, in the heart. In lamp2 null mice, intermittent fasting provoked progressive left ventricular dilation, systolic dysfunction and hypertrophy; worsening cardiomyocyte autophagosome accumulation and lack of protection to ischemia-reperfusion injury, suggesting that intact autophagy-lysosome machinery is essential for myocardial homeostasis during intermittent fasting and consequent ischemic cardioprotection. Fasting and refeeding cycles resulted in transcriptional induction followed by downregulation of autophagy-lysosome genes in the myocardium. This was coupled with fasting-induced nuclear translocation of TFEB (transcription factor EB), a master regulator of autophagy-lysosome machinery; followed by rapid decline in nuclear TFEB levels with refeeding. Endogenous TFEB was essential for attenuation of hypoxia-reoxygenation-induced cell death by repetitive starvation, in neonatal rat cardiomyocytes, in-vitro. Taken together, these data suggest that TFEB-mediated transcriptional priming of the autophagy-lysosome machinery mediates the beneficial effects of fasting-induced autophagy in myocardial ischemia-reperfusion injury.

  13. Predictors of response to repetitive transcranial magnetic stimulation (rTMS) in the treatment of major depressive disorder.

    PubMed

    Beuzon, G; Timour, Q; Saoud, M

    2017-02-01

    Repetitive transcranial magnetic stimulation (rTMS), based on the principle of electromagnetic induction, consists of applying series of magnetic impulses to the cerebral cortex so as to modulate neurone activity in a target zone. This technique, still experimental, could prove promising in the field of psychiatry, in particular for the treatment of major depressive disorder. It is important for the clinician to be able to assess the response potential of a given patient to rTMS, and this among other things requires relevant predictive factors to be available. This review of the literature aims to determine and analyse reported predictive factors for therapeutic response to rTMS treatment in major depressive disorder. Different parameters are studied, in particular age, the severity of the depressive episode, psychological dimensions, genetic factors, cerebral blood flows via cerebral imagery, and neuronavigation. The factors found to be associated with better therapeutic response were young age, low level of severity of the depressive episode, motor threshold intensity over 100%, more than 1000 stimulations per session, more than 10 days treatment, L/L genotype on the 5-HTTLPR transporter gene, C/C homozygosity on the promotor regions of the 5-HT1A receptor gene, Val/Val homozygosity on the BDNF gene, cordance analyses by EEG, and finally the accurate localisation provided by neuronavigation. The authors conclude that investigations in larger patient samples are required in the future, and that the work already achieved should provide lines of approach for the coming experimental studies. Copyright © 2016 L'Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.

  14. Consensus Recommendations for the Clinical Application of Repetitive Transcranial Magnetic Stimulation (rTMS) in the Treatment of Depression.

    PubMed

    McClintock, Shawn M; Reti, Irving M; Carpenter, Linda L; McDonald, William M; Dubin, Marc; Taylor, Stephan F; Cook, Ian A; O'Reardon, John; Husain, Mustafa M; Wall, Christopher; Krystal, Andrew D; Sampson, Shirlene M; Morales, Oscar; Nelson, Brent G; Latoussakis, Vassilios; George, Mark S; Lisanby, Sarah H

    2017-05-23

    To provide expert recommendations for the safe and effective application of repetitive transcranial magnetic stimulation (rTMS) in the treatment of major depressive disorder (MDD). Participants included a group of 17 expert clinicians and researchers with expertise in the clinical application of rTMS, representing both the National Network of Depression Centers (NNDC) rTMS Task Group and the American Psychiatric Association Council on Research (APA CoR) Task Force on Novel Biomarkers and Treatments. The consensus statement is based on a review of extensive literature from 2 databases (OvidSP MEDLINE and PsycINFO) searched from 1990 through 2016. The search terms included variants of major depressive disorder and transcranial magnetic stimulation. The results were limited to articles written in English that focused on adult populations. Of the approximately 1,500 retrieved studies, a total of 118 publications were included in the consensus statement and were supplemented with expert opinion to achieve consensus recommendations on key issues surrounding the administration of rTMS for MDD in clinical practice settings. In cases in which the research evidence was equivocal or unclear, a consensus decision on how rTMS should be administered was reached by the authors of this article and is denoted in the article as "expert opinion." Multiple randomized controlled trials and published literature have supported the safety and efficacy of rTMS antidepressant therapy. These consensus recommendations, developed by the NNDC rTMS Task Group and APA CoR Task Force on Novel Biomarkers and Treatments, provide comprehensive information for the safe and effective clinical application of rTMS in the treatment of MDD.

  15. Repetitive stimulation of autophagy-lysosome machinery by intermittent fasting preconditions the myocardium to ischemia-reperfusion injury

    PubMed Central

    Godar, Rebecca J; Ma, Xiucui; Liu, Haiyan; Murphy, John T; Weinheimer, Carla J; Kovacs, Attila; Crosby, Seth D; Saftig, Paul; Diwan, Abhinav

    2015-01-01

    Autophagy, a lysosomal degradative pathway, is potently stimulated in the myocardium by fasting and is essential for maintaining cardiac function during prolonged starvation. We tested the hypothesis that intermittent fasting protects against myocardial ischemia-reperfusion injury via transcriptional stimulation of the autophagy-lysosome machinery. Adult C57BL/6 mice subjected to 24-h periods of fasting, every other day, for 6 wk were protected from in-vivo ischemia-reperfusion injury on a fed day, with marked reduction in infarct size in both sexes as compared with nonfasted controls. This protection was lost in mice heterozygous null for Lamp2 (coding for lysosomal-associated membrane protein 2), which demonstrate impaired autophagy in response to fasting with accumulation of autophagosomes and SQSTM1, an autophagy substrate, in the heart. In lamp2 null mice, intermittent fasting provoked progressive left ventricular dilation, systolic dysfunction and hypertrophy; worsening cardiomyocyte autophagosome accumulation and lack of protection to ischemia-reperfusion injury, suggesting that intact autophagy-lysosome machinery is essential for myocardial homeostasis during intermittent fasting and consequent ischemic cardioprotection. Fasting and refeeding cycles resulted in transcriptional induction followed by downregulation of autophagy-lysosome genes in the myocardium. This was coupled with fasting-induced nuclear translocation of TFEB (transcription factor EB), a master regulator of autophagy-lysosome machinery; followed by rapid decline in nuclear TFEB levels with refeeding. Endogenous TFEB was essential for attenuation of hypoxia-reoxygenation-induced cell death by repetitive starvation, in neonatal rat cardiomyocytes, in-vitro. Taken together, these data suggest that TFEB-mediated transcriptional priming of the autophagy-lysosome machinery mediates the beneficial effects of fasting-induced autophagy in myocardial ischemia-reperfusion injury. PMID:26103523

  16. Repetitive Peripheral Magnetic Stimulation (15 Hz RPMS) of the Human Soleus Muscle did not Affect Spinal Excitability

    PubMed Central

    Behrens, Martin; Mau-Möller, Anett; Zschorlich, Volker; Bruhn, Sven

    2011-01-01

    The electric field induced by repetitive peripheral magnetic stimulation (RPMS) is able to activate muscles artificially due to the stimulation of deep intramuscular motor axons. RPMS applied to the muscle induces proprioceptive input to the central nervous system in different ways. Firstly, the indirect activation of mechanoreceptors and secondly, direct activation of afferent nerve fibers. The purpose of the study was to examine the effects of RPMS applied to the soleus. Thirteen male subjects received RPMS once and were investigated before and after the treatment regarding the parameters maximal M wave (Mmax), maximal H-reflex (Hmax), Hmax/Mmax-ratio, Hmax and Mmax onset latencies and plantar flexor peak twitch torque associated with Hmax (PTH). Eleven male subjects served as controls. No significant changes were observed for Hmax and PTH of the treatment group but the Hmax/Mmax-ratio increased significantly (p = 0.015) on account of a significantly decreased Mmax (p = 0.027). Hmax onset latencies were increased for the treatment group (p = 0.003) as well as for the control group (p = 0.011) while Mmax onset latencies did not change. It is concluded that the RPMS protocol did not affect spinal excitability but acted on the muscle fibres which are part of fast twitch units and mainly responsible for the generation of the maximal M wave. RPMS probably modified the integrity of neuromuscular propagation. Key points RPMS probably did not affect spinal excitability. Data suggested that RPMS likely acted on the muscle fibres which are part of fast twitch units and mainly responsible for the generation of the maximal M wave. RPMS probably modified the integrity of neuromuscular propagation. PMID:24149293

  17. Longlasting antalgic effects of daily sessions of repetitive transcranial magnetic stimulation in central and peripheral neuropathic pain

    PubMed Central

    Khedr, E; Kotb, H; Kamel, N; Ahmed, M; Sadek, R; Rothwell, J

    2005-01-01

    Background and objective: A single session of repetitive transcranial magnetic stimulation (rTMS) over motor cortex had been reported to produce short term relief of some types of chronic pain. The present study investigated whether five consecutive days of rTMS would lead to longer lasting pain relief in unilateral chronic intractable neuropathic pain. Patients and methods: Forty eight patients with therapy resistant chronic unilateral pain syndromes (24 each with trigeminal neuralgia (TGN) and post-stroke pain syndrome (PSP)) participated. Fourteen from each group received 10 minutes real rTMS over the hand area of motor cortex (20 Hz, 10x10 s trains, intensity 80% of motor threshold) every day for five consecutive days. The remaining patients received sham stimulation. Pain was assessed using a visual analogue scale (VAS) and the Leeds assessment of neuropathic symptoms and signs (LANSS) scale, before, after the first, fourth, and fifth sessions, and two weeks after the last session. Results: No significant differences were found in basal pain ratings between patients receiving real- and sham-rTMS. However, a two factor ANOVA revealed a significant "± TMS" x "time" interaction indicating that real and sham rTMS had different effects on the VAS and LANSS scales. Post hoc testing showed that in both groups of patients, real-rTMS led to a greater improvement in scales than sham-rTMS, evident even two weeks after the end of the treatment. No patient experienced adverse effects. Conclusion: These results confirm that five daily sessions of rTMS over motor cortex can produce longlasting pain relief in patients with TGN or PSP. PMID:15897507

  18. Impact of Repetitive Transcranial Magnetic Stimulation on Post-Stroke Dysmnesia and the Role of BDNF Val66Met SNP

    PubMed Central

    Lu, Haitao; Zhang, Tong; Wen, Mei; Sun, Li

    2015-01-01

    Background Little is known about the effects of low-frequency repetitive transcranial magnetic stimulation (rTMS) on dysmnesia and the impact of brain nucleotide neurotrophic factor (BDNF) Val66Met single-nucleotide polymorphism (SNP). This study investigated the impact of low-frequency rTMS on post-stroke dysmnesia and the impact of BDNF Val66Met SNP. Material/Methods Forty patients with post-stroke dysmnesia were prospectively randomized into the rTMS and sham groups. BDNF Val66Met SNP was determined using restriction fragment length polymorphism. Montreal Cognitive Assessment (MoCA), Loewenstein Occupational Therapy of Cognitive Assessment (LOTCA), and Rivermead Behavior Memory Test (RBMT) scores, as well as plasma BDNF concentrations, were measured at baseline and at 3 days and 2 months post-treatment. Results MoCA, LOTCA, and RBMT scores were higher after rTMS. Three days after treatment, BDNF decreased in the rTMS group but it increased in the sham group (P<0.05). Two months after treatment, RMBT scores in the rTMS group were higher than in the sham group, but not MoCA and LOTCA scores. Conclusions Low-frequency rTMS may improve after-stoke memory through various pathways, which may involve polymorphisms and several neural genes, but not through an increase in BDNF levels. PMID:25770310

  19. Repetitive transcranial magnetic stimulation induced slow wave activity modification: A possible role in disorder of consciousness differential diagnosis?

    PubMed

    Pisani, Laura Rosa; Naro, Antonino; Leo, Antonino; Aricò, Irene; Pisani, Francesco; Silvestri, Rosalia; Bramanti, Placido; Calabrò, Rocco Salvatore

    2015-12-15

    Slow wave activity (SWA) generation depends on cortico-thalamo-cortical loops that are disrupted in patients with chronic Disorders of Consciousness (DOC), including the Unresponsive Wakefulness Syndrome (UWS) and the Minimally Conscious State (MCS). We hypothesized that the modulation of SWA by means of a repetitive transcranial magnetic stimulation (rTMS) could reveal residual patterns of connectivity, thus supporting the DOC clinical differential diagnosis. We enrolled 10 DOC individuals who underwent a 24hh polysomnography followed by a real or sham 5Hz-rTMS over left primary motor area, and a second polysomnographic recording. A preserved sleep-wake cycle, a standard temporal progression of sleep stages, and a SWA perturbation were found in all of the MCS patients and in none of the UWS individuals, only following the real-rTMS. In conclusion, our combined approach may improve the differential diagnosis between MCS patients, who show a partial preservation of cortical plasticity, and UWS individuals, who lack such properties.

  20. Analgesic effect of repetitive transcranial magnetic stimulation (rTMS) in patients with chronic low back pain.

    PubMed

    Ambriz-Tututi, Mónica; Alvarado-Reynoso, Beatriz; Drucker-Colín, René

    2016-08-22

    The objective of the present study was to assess the benefits of 1-week repetitive transcranial magnetic stimulation (rTMS) in patients with chronic low back pain (LBP). The visual analogue scale (VAS), Short Form McGill pain questionnaire (SF-MPQ), and Short Form 36 Health Survey were used to evaluate the effect of this treatment. Eighty-two patients diagnosed with LBP were divided randomly into three groups: rTMS-treated group, sham group, and physical therapy-treated group. We observed a significant reduction in VAS and SF-MPQ scores in the rTMS-treated group, but not in the sham group. Moreover, patients who received rTMS had a lower mean pain score than patients treated with physical therapy. Our study suggests that rTMS produces safe, significant, and long-term relief in patients with LBP without evident side effects. This study shows for the first time that long-term repeated sessions of rTMS decrease pain perception of LBP. Bioelectromagnetics. © 2016 Wiley Periodicals, Inc.

  1. Repetitive transcranial magnetic stimulation for tinnitus treatment: no enhancement by the dopamine and noradrenaline reuptake inhibitor bupropion.

    PubMed

    Kleinjung, Tobias; Steffens, Thomas; Landgrebe, Michael; Vielsmeier, Veronika; Frank, Elmar; Burger, Julia; Strutz, Juergen; Hajak, Göran; Langguth, Berthold

    2011-04-01

    Repetitive transcranial magnetic stimulation (rTMS) of the temporal cortex has shown beneficial effects in patients with chronic tinnitus. Recent preclinical data in healthy controls suggest that the effects of low-frequency rTMS can be enhanced by dopaminergic drugs. We investigated whether application of the dopamine reuptake inhibitor bupropion increases the clinical effects of low-frequency rTMS over the auditory cortex in tinnitus patients. Eighteen subjects with chronic tinnitus received 10 sessions of 1 Hz rTMS (2000 pulses/day, 110% motor threshold) applied to the left temporal cortex. In addition, these subjects received one dosage of 150 mg bupropion (Wellbutrin XL/Elontril) 4 hours before each TMS session. Treatment outcome was assessed with a tinnitus questionnaire over a 3-month period. Treatment effects were compared with a control group of 100 tinnitus patients matched for age, tinnitus duration, and tinnitus questionnaire baseline scores, who received the same rTMS treatment without prior bupropion application. For the whole sample, there was a significant effect of rTMS treatment over time. There were no significant differences between the bupropion and the control group. Our data suggest that 150 mg bupropion administration does not enhance the effect of rTMS in the treatment of tinnitus. Copyright © 2011 Elsevier Inc. All rights reserved.

  2. Benefit of multiple sessions of perilesional repetitive transcranial magnetic stimulation for an effective rehabilitation of visuospatial function.

    PubMed

    Afifi, Linda; Jarrett Rushmore, R; Valero-Cabré, Antoni

    2013-02-01

    Noninvasive neurostimulation techniques have been used alone or in conjunction with rehabilitation therapy to treat the neurological sequelae of brain damage with rather variable therapeutic outcomes. One potential factor limiting a consistent success for such techniques may be the limited number of sessions carried out in patients, despite reports that their accrual may play a key role in alleviating neurological deficits long-term. In this study, we tested the effects of seventy consecutive sessions of perilesional high-frequency (10 Hz) repetitive transcranial magnetic stimulation (rTMS) in the treatment of chronic neglect deficits in a well-established feline model of visuospatial neglect. Under identical rTMS parameters and visuospatial testing regimes, half of the subjects improved in visuospatial orienting performance. The other half experienced either none or extremely moderate ameliorations in the neglected hemispace and displayed transient patterns of maladaptive visuospatial behavior. Detailed analyses suggest that lesion location and extent did not account for the behavioral differences observed between these two groups of animals. We conclude that multi-session perilesional rTMS regimes have the potential to induce functional ameliorations following focal chronic brain injury, and that behavioral performance prior to the onset of the rTMS treatment is the factor that best predicts positive outcomes for noninvasive neurostimulation treatments in visuospatial neglect.

  3. Benefit of Multiple Sessions of Perilesional Repetitive Transcranial Magnetic Stimulation for an Effective Rehabilitation of Visuo-Spatial Function

    PubMed Central

    Afifi, Linda; Rushmore, R. Jarrett; Valero-Cabré, Antoni

    2012-01-01

    Non-invasive neurostimulation techniques have been used alone or in conjunction with rehabilitation therapy to treat the neurological sequelae of brain damage with rather variable therapeutic outcomes. One potential factor limiting a consistent success for such techniques may be the few sessions carried out in patients, despite reports that their accrual may play a key role in alleviating neurological deficits long-term. In this study, we tested the effects of seventy consecutive sessions of perilesional high frequency (10 Hz) repetitive transcranial magnetic stimulation (rTMS) in the treatment of chronic neglect deficits in a well-established feline model of visuo-spatial neglect. Under identical rTMS parameters and visuo-spatial testing regimes, half of the subjects improved in visuo-spatial orienting performance. The other half experienced either none or extremely moderate ameliorations in the neglected hemispace and displayed transient patterns of maladaptive visuo-spatial behavior. Detailed analyses suggest that lesion location and extent did not account for the behavioral differences observed between these two groups of animals. We conclude that multi-session perilesional rTMS regimes have the potential to induce functional ameliorations following focal chronic brain injury, and that behavioral performance prior to the onset of the rTMS treatment is the factor that best predicts positive outcomes for non-invasive neurostimulation treatments in visuo-spatial neglect. PMID:23167832

  4. Effect of high-frequency repetitive transcranial magnetic stimulation on major depressive disorder in patients with Parkinson's disease.

    PubMed

    Shin, Hae-Won; Youn, Young C; Chung, Sun J; Sohn, Young H

    2016-07-01

    Major depressive disorder (MDD) occurs in a small proportion of patients with Parkinson's disease (PD) and reduces their quality of life. We performed a randomized sham-controlled study to evaluate the effect of high-frequency (HF) repetitive transcranial magnetic stimulation (rTMS) of the left dorsolateral prefrontal cortex (DLPFC) on MDD in patients with PD. Ten patients participated to a real-rTMS group and eight patients to a sham-rTMS group. Evaluations were performed at baseline, 2 and 6 weeks after rTMS treatment. All participants underwent examinations of depression rating scales, including the Hamilton Rating Scale, the Montgomery-Asberg Depression Rating Scale (MADRS), and the Beck Depression Inventory (BDI) and the motor part of the Unified Parkinson Disease Rating Scale (UPDRS-III). The real-rTMS group had improved scores on HRS and the MADRS after 10 sessions, and these beneficial effects persisted for 6 weeks after the initial session. The BDI score did not change immediately after the sessions. The sham-rTMS group had no significant changes in any of the depression rating scales. The UPDRS-III did not change in either group. HF-rTMS of the left DLPFC is an effective treatment for MDD in patients with PD.

  5. Neural correlates of dual-task practice benefit on motor learning: a repetitive transcranial magnetic stimulation study.

    PubMed

    Goh, Hui-Ting; Lee, Ya-Yun; Fisher, Beth E

    2013-06-01

    Dual-task practice has been previously shown to enhance motor learning when both primary and secondary tasks engage similar cognitive processes. In the present study, participants practiced a finger sequence task with the non-dominant hand under a single-task condition (i.e. without a probe task) or a dual-task condition in which a probe choice reaction time (CRT) task was presented during the preparation phase (before movement onset) of the finger task. It was hypothesised that by engaging similar 'planning' processes, the dual-task condition may facilitate the activation of shared 'planning' circuitry that includes dorsal premotor cortex (dPM), an important neural substrate for CRT task performance and movement preparation. Repetitive transcranial magnetic stimulation (rTMS; 1 Hz) was applied to the contralateral dPM immediately following practice. Motor learning was assessed by a retention test conducted ~ 24 h after practice. Consistent with our previous results, the dual-task condition enhanced learning compared with the single-task condition. rTMS applied to dPM attenuated the dual-task practice benefit on motor learning. In contrast, rTMS to M1 did not attenuate the dual-task practice benefit, suggesting the rTMS effect was specific to dPM. Our findings suggest a unique role of dPM in mediating the dual-task practice effect on motor learning. © 2013 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

  6. Repetitive Transcranial Magnetic Stimulation as an Adjunct to Constraint-Induced Therapy: An Exploratory Randomized Controlled Trial

    PubMed Central

    Malcolm, Matthew P.; Triggs, William J.; Light, Kathye E.; Gonzalez Rothi, Leslie J.; Wu, Sam; Reid, Kimberly; Nadeau, Stephen E.

    2008-01-01

    Objective To test the potential adjuvant effect of repetitive transcranial magnetic stimulation (rTMS) on motor learning in a group of stroke survivors undergoing constraint-induced therapy (CIT) for upper-limb hemiparesis. Design This was a prospective randomized, double-blind, sham-controlled, parallel group study. Nineteen individuals, one or more years poststroke, were randomized to either a rTMS + CIT (n = 9) or a sham rTMS + CIT (n = 10) group and participated in the 2-wk intervention. Results Regardless of group assignment, participants demonstrated significant gains on the primary outcome measures: the Wolf Motor Function Test (WMFT) and the Motor Activity Log (MAL)–Amount of Use, and on secondary outcome measures including the Box and Block Test (BBT) and the MAL–How Well. Participants receiving rTMS failed to show differential improvement on either primary outcome measure. Conclusions Although this study provided further evidence that even relatively brief sessions of CIT can have a substantial effect, it provided no support for adjuvant use of rTMS. PMID:17709994

  7. The effect of computer-assisted cognitive rehabilitation and repetitive transcranial magnetic stimulation on cognitive function for stroke patients.

    PubMed

    Park, In-Seok; Yoon, Jung-Gyu

    2015-03-01

    [Purpose] This study investigated the effects of computer-assisted cognitive rehabilitation (CACR) and repetitive transcranial magnetic stimulation (rTMS) on cognitive function in patients with stroke. [Subjects and Methods] We enrolled 20 patients and divided them into CACR and rTMS groups. CACR and rTMS were performed thrice a week for 4 weeks. Cognitive function was measured with the Korean Mini-Mental State Examination (K-MMSE) and Lowenstein Occupational Therapy Cognitive Assessment-Geriatric (LOTCA-G) before and after treatment. The independent samples t-test was performed to test the homogeneity of K-MMSE and LOTCA-G before treatment and compare the differences in cognitive improvement between the CACR and rTMS groups. A paired samples t-test was used to compare cognitive function before and after treatment. [Results] Cognitive function of both the groups significantly improved after the intervention based on the K-MMSE and LOTCA-G scores. While the LOTCA-G score improved significantly more in the CACR group than in the rTMS group, no significant difference was seen in the K-MMSE scores. [Conclusion] We showed that CACR is more effective than rTMS in improving cognitive function after stroke.

  8. Clinical improvement in patients with borderline personality disorder after treatment with repetitive transcranial magnetic stimulation: preliminary results.

    PubMed

    Reyes-López, Julian; Ricardo-Garcell, Josefina; Armas-Castañeda, Gabriela; García-Anaya, María; Arango-De Montis, Iván; González-Olvera, Jorge J; Pellicer, Francisco

    2017-06-12

    Current treatment of borderline personality disorder (BPD) consists of psychotherapy and pharmacological interventions. However, the use of repetitive transcranial magnetic stimulation (rTMS) could be beneficial to improve some BPD symptoms. The objective of this study was to evaluate clinical improvement in patients with BPD after application of rTMS over the right or left dorsolateral prefrontal cortex (DLPFC). Twenty-nine patients with BPD from the National Institute of Psychiatry, Mexico, were randomized in two groups to receive 15 sessions of rTMS applied over the right (1 Hz, n=15) or left (5 Hz, n=14) DLPFC. Improvement was measured by the Clinical Global Impression Scale for BPD (CGI-BPD), Borderline Evaluation of Severity Over Time (BEST), Beck Depression Inventory (BDI), Hamilton Anxiety Rating Scale (HAM-A), and Barratt Impulsiveness Scale (BIS). Intragroup comparison showed significant (p < 0.05) reductions in every psychopathologic domain of the CGI-BPD and in the total scores of all scales in both groups. Both protocols produced global improvement in severity and symptoms of BPD, particularly in impulsiveness, affective instability, and anger. Further studies are warranted to explore the therapeutic effect of rTMS in BPD. NCT02273674

  9. Involvement of the superior temporal cortex and the occipital cortex in spatial hearing: evidence from repetitive transcranial magnetic stimulation.

    PubMed

    Lewald, Jörg; Meister, Ingo G; Weidemann, Jürgen; Töpper, Rudolf

    2004-06-01

    The processing of auditory spatial information in cortical areas of the human brain outside of the primary auditory cortex remains poorly understood. Here we investigated the role of the superior temporal gyrus (STG) and the occipital cortex (OC) in spatial hearing using repetitive transcranial magnetic stimulation (rTMS). The right STG is known to be of crucial importance for visual spatial awareness, and has been suggested to be involved in auditory spatial perception. We found that rTMS of the right STG induced a systematic error in the perception of interaural time differences (a primary cue for sound localization in the azimuthal plane). This is in accordance with the recent view, based on both neurophysiological data obtained in monkeys and human neuroimaging studies, that information on sound location is processed within a dorsolateral "where" stream including the caudal STG. A similar, but opposite, auditory shift was obtained after rTMS of secondary visual areas of the right OC. Processing of auditory information in the OC has previously been shown to exist only in blind persons. Thus, the latter finding provides the first evidence of an involvement of the visual cortex in spatial hearing in sighted human subjects, and suggests a close interconnection of the neural representation of auditory and visual space. Because rTMS induced systematic shifts in auditory lateralization, but not a general deterioration, we propose that rTMS of STG or OC specifically affected neuronal circuits transforming auditory spatial coordinates in order to maintain alignment with vision.

  10. Impact of repetitive transcranial magnetic stimulation on post-stroke dysmnesia and the role of BDNF Val66Met SNP.

    PubMed

    Lu, Haitao; Zhang, Tong; Wen, Mei; Sun, Li

    2015-03-14

    Little is known about the effects of low-frequency repetitive transcranial magnetic stimulation (rTMS) on dysmnesia and the impact of brain nucleotide neurotrophic factor (BDNF) Val66Met single-nucleotide polymorphism (SNP). This study investigated the impact of low-frequency rTMS on post-stroke dysmnesia and the impact of BDNF Val66Met SNP. Forty patients with post-stroke dysmnesia were prospectively randomized into the rTMS and sham groups. BDNF Val66Met SNP was determined using restriction fragment length polymorphism. Montreal Cognitive Assessment (MoCA), Loewenstein Occupational Therapy of Cognitive Assessment (LOTCA), and Rivermead Behavior Memory Test (RBMT) scores, as well as plasma BDNF concentrations, were measured at baseline and at 3 days and 2 months post-treatment. MoCA, LOTCA, and RBMT scores were higher after rTMS. Three days after treatment, BDNF decreased in the rTMS group but it increased in the sham group (P<0.05). Two months after treatment, RMBT scores in the rTMS group were higher than in the sham group, but not MoCA and LOTCA scores. Low-frequency rTMS may improve after-stoke memory through various pathways, which may involve polymorphisms and several neural genes, but not through an increase in BDNF levels.

  11. The effect of computer-assisted cognitive rehabilitation and repetitive transcranial magnetic stimulation on cognitive function for stroke patients

    PubMed Central

    Park, In-Seok; Yoon, Jung-Gyu

    2015-01-01

    [Purpose] This study investigated the effects of computer-assisted cognitive rehabilitation (CACR) and repetitive transcranial magnetic stimulation (rTMS) on cognitive function in patients with stroke. [Subjects and Methods] We enrolled 20 patients and divided them into CACR and rTMS groups. CACR and rTMS were performed thrice a week for 4 weeks. Cognitive function was measured with the Korean Mini-Mental State Examination (K-MMSE) and Lowenstein Occupational Therapy Cognitive Assessment-Geriatric (LOTCA-G) before and after treatment. The independent samples t-test was performed to test the homogeneity of K-MMSE and LOTCA-G before treatment and compare the differences in cognitive improvement between the CACR and rTMS groups. A paired samples t-test was used to compare cognitive function before and after treatment. [Results] Cognitive function of both the groups significantly improved after the intervention based on the K-MMSE and LOTCA-G scores. While the LOTCA-G score improved significantly more in the CACR group than in the rTMS group, no significant difference was seen in the K-MMSE scores. [Conclusion] We showed that CACR is more effective than rTMS in improving cognitive function after stroke. PMID:25931728

  12. Geophysical Imaging of Stimulated Microbial Biomineralization

    SciTech Connect

    Williams, Kenneth H.; Ntarlagiannis, Dimitrios; Slater, Lee D.; Dohnalkova, Alice; Hubbard, Susan S.; Banfield, Jillian F.

    2005-10-01

    Understanding how microorganisms influence the physical and chemical properties of the subsurface is hindered by our inability to observe microbial dynamics in real time and with high spatial resolution. Here, we investigate the use of noninvasive geophysical methods to monitor biomineralization at the laboratory scale during stimulated sulfate reduction under dynamic flow conditions. Alterations in sediment characteristics resulting from microbe-mediated sulfide mineral precipitation were concomitant with changes in complex resistivity and acoustic wave propagation signatures. The sequestration of zinc and iron in insoluble sulfides led to alterations in the ability of the pore fluid to conduct electrical charge and of the saturated sediments to dissipate acoustic energy. These changes resulted directly from the nucleation, growth, and development of nanoparticulate precipitates along grain surfaces and within the pore space. Scanning and transmission electron microscopy (SEM and TEM) confirmed the sulfides to be associated with cell surfaces, with precipitates ranging from aggregates of individual 3-5 nm nanocrystals to larger assemblages of up to 10-20 ím in diameter. Anomalies in the geophysical data reflected the distribution of mineral precipitates and biomass over space and time, with temporal variations in the signals corresponding to changes in the aggregation state of the nanocrystalline sulfides. These results suggest the potential for using geophysical techniques to image certain subsurface biogeochemical processes, such as those accompanying the bioremediation of metalcontaminated aquifers.

  13. Acoustic evaluation of short-term effects of repetitive transcranial magnetic stimulation on motor aspects of speech in Parkinson's disease.

    PubMed

    Eliasova, I; Mekyska, J; Kostalova, M; Marecek, R; Smekal, Z; Rektorova, I

    2013-04-01

    Hypokinetic dysarthria in Parkinson's disease (PD) can be characterized by monotony of pitch and loudness, reduced stress, variable rate, imprecise consonants, and a breathy and harsh voice. Using acoustic analysis, we studied the effects of high-frequency repetitive transcranial magnetic stimulation (rTMS) applied over the primary orofacial sensorimotor area (SM1) and the left dorsolateral prefrontal cortex (DLPFC) on motor aspects of voiced speech in PD. Twelve non-depressed and non-demented men with PD (mean age 64.58 ± 8.04 years, mean PD duration 10.75 ± 7.48 years) and 21 healthy age-matched men (a control group, mean age 64 ± 8.55 years) participated in the speech study. The PD patients underwent two sessions of 10 Hz rTMS over the dominant hemisphere with 2,250 stimuli/day in a random order: (1) over the SM1; (2) over the left DLPFC in the "on" motor state. Speech examination comprised the perceptual rating of global speech performance and an acoustic analysis based upon a standardized speech task. The Mann-Whitney U test was used to compare acoustic speech variables between controls and PD patients. The Wilcoxon test was used to compare data prior to and after each stimulation in the PD group. rTMS applied over the left SM1 was associated with a significant increase in harmonic-to-noise ratio and net speech rate in the sentence tasks. With respect to the vowel task results, increased median values and range of Teager-Kaiser energy operator, increased vowel space area, and significant jitter decrease were observed after the left SM1 stimulation. rTMS over the left DLPFC did not induce any significant effects. The positive results of acoustic analysis were not reflected in a subjective rating of speech performance quality as assessed by a speech therapist. Our pilot results indicate that one session of rTMS applied over the SM1 may lead to measurable improvement in voice quality and intensity and an increase in speech rate and tongue movements

  14. Safety and tolerability of repetitive transcranial magnetic stimulation in patients with epilepsy: a review of the literature.

    PubMed

    Bae, Erica Hyunji; Schrader, Lara M; Machii, Katsuyuki; Alonso-Alonso, Miguel; Riviello, James J; Pascual-Leone, Alvaro; Rotenberg, Alexander

    2007-06-01

    Repetitive transcranial magnetic stimulation (rTMS) is emerging as a new therapeutic tool in epilepsy, where it can be used to suppress seizures or treat comorbid conditions such as mood disorder. However, as rTMS carries a risk of inducing seizures among other adverse events, its safety and tolerability in the population with epilepsy warrant distinct consideration, as this group is especially seizure-prone. Accordingly, we performed a review of the literature to estimate the risk of seizures and other adverse events associated with rTMS in patients with epilepsy. We performed an English-language literature search, and reviewed all studies published from January 1990 to February 2007 in which patients with epilepsy were treated with rTMS, and complemented the literature search with personal correspondence with authors when necessary. We identified 30 publications that described patients with epilepsy who underwent rTMS, and noted total number of relevant subjects, medication usage, incidence of adverse events, and rTMS parameters including stimulus frequency, number of stimuli, train duration, intertrain interval, coil type, and stimulation sites. The data were analyzed for adverse events related to rTMS. Crude per-subject risk, as well as per-subject mean risk weighted by sample size and risk per 1000 stimuli weighted by number of stimuli in each study, were computed for seizures and for other adverse events. Adverse events or lack thereof was reported in 26 studies (n=280 subjects). Adverse events attributed to rTMS were generally mild and occurred in 17.1% of subjects. Headache was most common, occurring in 9.6%. The most serious adverse event was seizure during treatment, which occurred in four patients (1.4% crude per-subject risk). All but one case were the patients' typical seizures with respect to duration and semiology, and were associated with low-frequency rTMS. A single case of an atypical seizure appearing to arise from the region of stimulation

  15. Repetitive transcranial magnetic stimulation (rTMS) influences spatial cognition and modulates hippocampal structural synaptic plasticity in aging mice.

    PubMed

    Ma, Jun; Zhang, Zhanchi; Kang, Lin; Geng, Dandan; Wang, Yanyong; Wang, Mingwei; Cui, Huixian

    2014-10-01

    Normal aging is characteristic with the gradual decline in cognitive function associated with the progressive reduction of structural and functional plasticity in the hippocampus. Repetitive transcranial magnetic stimulation (rTMS) has developed into a novel neurological and psychiatric tool that can be used to investigate the neurobiology of cognitive function. Recent studies have demonstrated that low-frequency rTMS (≤1Hz) affects synaptic plasticity in rats with vascular dementia (VaD), and it ameliorates the spatial cognitive ability in mice with Aβ1-42-mediated memory deficits, but there are little concerns about the effects of rTMS on normal aging related cognition and synaptic plasticity changes. Thus, the current study investigated the effects of rTMS on spatial memory behavior, neuron and synapse morphology in the hippocampus, and synaptic protein markers and brain-derived neurotrophic factor (BDNF)/tropomyosin-related kinase B (TrkB) in normal aging mice, to illustrate the mechanisms of rTMS in regulating cognitive capacity. Relative to adult animals, aging caused hippocampal-dependent cognitive impairment, simultaneously inhibited the activation of the BDNF-TrkB signaling pathway, reduced the transcription and expression of synaptic protein markers: synaptophysin (SYN), growth associated protein 43 (GAP43) and post-synaptic density protein 95 (PSD95), as well as decreased synapse density and PSD (post-synaptic density) thickness. Interestingly, rTMS with low intensity (110% average resting motor threshold intensity, 1Hz, LIMS) triggered the activation of BDNF and TrkB, upregulated the level of synaptic protein markers, and increased synapse density and thickened PSD, and further reversed the spatial cognition dysfunction in aging mice. Conversely, high-intensity magnetic stimulation (150% average resting motor threshold intensity, 1Hz, HIMS) appeared to be detrimental, inducing thinning of PSDs, disordered synaptic structure, and a large number of

  16. Fractional averaging of repetitive waveforms induced by self-imaging effects

    NASA Astrophysics Data System (ADS)

    Romero Cortés, Luis; Maram, Reza; Azaña, José

    2015-10-01

    We report the theoretical prediction and experimental observation of averaging of stochastic events with an equivalent result of calculating the arithmetic mean (or sum) of a rational number of realizations of the process under test, not necessarily limited to an integer record of realizations, as discrete statistical theory dictates. This concept is enabled by a passive amplification process, induced by self-imaging (Talbot) effects. In the specific implementation reported here, a combined spectral-temporal Talbot operation is shown to achieve undistorted, lossless repetition-rate division of a periodic train of noisy waveforms by a rational factor, leading to local amplification, and the associated averaging process, by the fractional rate-division factor.

  17. Brain imaging correlates of peripheral nerve stimulation

    PubMed Central

    Bari, Ausaf A.; Pouratian, Nader

    2012-01-01

    Direct peripheral nerve stimulation is an effective treatment for a number of disorders including epilepsy, depression, neuropathic pain, cluster headache, and urological dysfunction. The efficacy of this stimulation is ultimately due to modulation of activity in the central nervous system. However, the exact brain regions involved in each disorder and how they are modulated by peripheral nerve stimulation is not fully understood. The use of functional neuroimaging such as SPECT, PET and fMRI in patients undergoing peripheral nerve stimulation can help us to understand these mechanisms. We review the literature for functional neuroimaging performed in patients implanted with peripheral nerve stimulators for the above-mentioned disorders. These studies suggest that brain activity in response to peripheral nerve stimulation is a complex interaction between the stimulation parameters, disease type and severity, chronicity of stimulation, as well as nonspecific effects. From this information we may be able to understand which brain structures are involved in the mechanism of peripheral nerve stimulation as well as define the neural substrates underlying these disorders. PMID:23230531

  18. Repetitive Transcranial Magnetic Stimulation for Treatment-Resistant Depression: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

    PubMed Central

    Sehatzadeh, Shayan; Tu, Hong Anh; Palimaka, Stefan; Yap, Belinda; O'Reilly, Daria; Bowen, Jim; Higgins, Caroline; Holubowich, Corinne

    2016-01-01

    Background To date, several randomized controlled trials (RCTs) have shown the efficacy of repetitive transcranial magnetic stimulation (rTMS) in the treatment of major depression. Objective This analysis examined the antidepressant efficacy of rTMS in patients with treatment-resistant unipolar depression. Methods A literature search was performed for RCTs published from January 1, 1994, to November 20, 2014. The search was updated on March 1, 2015. Two independent reviewers evaluated the abstracts for inclusion, reviewed full texts of eligible studies, and abstracted data. Meta-analyses were conducted to obtain summary estimates. The primary outcome was changes in depression scores measured by the Hamilton Rating Scale for Depression (HRSD), and we considered, a priori, the mean difference of 3.5 points to be a clinically important treatment effect. Remission and response to the treatment were secondary outcomes, and we calculated number needed to treat on the basis of these outcomes. We examined the possibility of publication bias by constructing funnel plots and by Begg's and Egger's tests. A meta-regression was undertaken to examine the effect of specific rTMS technical parameters on the treatment effects. Results Twenty-three RCTs compared rTMS with sham, and six RCTs compared rTMS with electroconvulsive therapy (ECT). Trials of rTMS versus sham showed a statistically significant improvement in depression scores with rTMS (weighted mean difference [WMD] 2.31, 95% CI 1.19–3.43; P < .001). This improvement was smaller than the pre-specified clinically important treatment effect. There was a 10% absolute difference between rTMS and sham in the rates of remission or response. This translates to a number needed to treat of 10. Risk ratios for remission and response were 2.20 (95% CI 1.44–3.38, P = .001 and 1.72 [95% CI], 1.13–2.62, P = .01), respectively, favouring rTMS. No publication bias was detected. Trials of rTMS versus ECT showed a statistically and

  19. Primed low-frequency repetitive transcranial magnetic stimulation and constraint-induced movement therapy in pediatric hemiparesis: a randomized trial

    PubMed Central

    GILLICK, BERNADETTE T; KRACH, LINDA E; FEYMA, TIM; RICH, TONYA L; MOBERG, KELLI; THOMAS, WILLIAM; CASSIDY, JESSICA M; MENK, JEREMIAH; CAREY, JAMES R

    2013-01-01

    Aim The aim of this study was to determine the feasibility and efficacy of five treatments of 6Hz primed, low-frequency, repetitive transcranial magnetic stimulation (rTMS) combined with constraint-induced movement therapy (CIMT) to promote recovery of the paretic hand in children with congenital hemiparesis. Method Nineteen children with congenital hemiparesis aged between 8 and 17 years (10 males, nine females; mean age 10y 10mo, SD 2y 10mo; Manual Ability Classification Scale levels I-III) underwent five sessions of either real rTMS (n=10) or sham rTMS (n=9) alternated daily with CIMT. CIMT consisted of 13 days of continuous long-arm casting with five skin-check sessions. Each child received a total of 10 hours of one-to-one therapy. The primary outcome measure was the Assisting Hand Assessment (AHA) and the secondary outcome variables were the Canadian Occupational Performance Measure (COPM) and stereognosis. A Wilcoxon signed-rank sum test was used to analyze differences between pre- and post-test scores within the groups. Analysis of covariance was used to compute mean differences between groups adjusting for baseline. Fisher’s exact test was used to compare individual change in AHA raw scores with the smallest detectable difference (SDD) of 4 points. Results All participants receiving treatment finished the study. Improvement in AHA differed significantly between groups (p=0.007). No significant differences in the secondary outcome measures were found. Eight out of 10 participants in the rTMS/CIMT group showed improvement greater than the SDD, but only two out of nine in the sham rTMS/CIMT group showed such improvement (p=0.023). No serious adverse events occurred. Interpretation Primed, low-frequency rTMS combined with CIMT appears to be safe, feasible, and efficacious in pediatric hemiparesis. Larger clinical trials are now indicated. PMID:23962321

  20. A double-blind, randomized trial of deep repetitive transcranial magnetic stimulation (rTMS) for autism spectrum disorder.

    PubMed

    Enticott, Peter G; Fitzgibbon, Bernadette M; Kennedy, Hayley A; Arnold, Sara L; Elliot, David; Peachey, Amy; Zangen, Abraham; Fitzgerald, Paul B

    2014-01-01

    Biomedical treatment options for autism spectrum disorder (ASD) are extremely limited. Repetitive transcranial magnetic stimulation (rTMS) is a safe and efficacious technique when targeting specific areas of cortical dysfunction in major depressive disorder, and a similar approach could yield therapeutic benefits in ASD, if applied to relevant cortical regions. The aim of this study was to examine whether deep rTMS to bilateral dorsomedial prefrontal cortex improves social relating in ASD. 28 adults diagnosed with either autistic disorder (high-functioning) or Asperger's disorder completed a prospective, double-blind, randomized, placebo-controlled design with 2 weeks of daily weekday treatment. This involved deep rTMS to bilateral dorsomedial prefrontal cortex (5 Hz, 10-s train duration, 20-s inter-train interval) for 15 min (1500 pulses per session) using a HAUT-Coil. The sham rTMS coil was encased in the same helmet of the active deep rTMS coil, but no effective field was delivered into the brain. Assessments were conducted before, after, and one month following treatment. Participants in the active condition showed a near significant reduction in self-reported social relating symptoms from pre-treatment to one month follow-up, and a significant reduction in social relating symptoms (relative to sham participants) for both post-treatment assessments. Those in the active condition also showed a reduction in self-oriented anxiety during difficult and emotional social situations from pre-treatment to one month follow-up. There were no changes for those in the sham condition. Deep rTMS to bilateral dorsomedial prefrontal cortex yielded a reduction in social relating impairment and socially-related anxiety. Further research in this area should employ extended rTMS protocols that approximate those used in depression in an attempt to replicate and amplify the clinical response. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Repetitive transcranial magnetic stimulation (rTMS) improves behavioral and biochemical deficits in levodopa-induced dyskinetic rats model

    PubMed Central

    Guan, Lina; Yi, Maoli; Zhang, Hongli

    2016-01-01

    Fluctuations of dopamine levels and upregulations of NR2B tyrosine phosphorylation in the striatum have been connected with levodopa (L-dopa)-induced dyskinesia (LID) in Parkinson's disease (PD). Repetitive transcranial magnetic stimulation (rTMS) is one of the noninvasive and potential method treating dyskinesia. Yet, the effect of rTMS on the above key pathological events remains unclear. In this study, we gave L-dopa treatment intraperitoneally for 22 days to 6-hydroxydopamine-lesioned PD rats to prepare LID rats model, and subsequently applied rTMS daily for 3 weeks to LID rats model. The effect of rTMS on abnormal involuntary movements (AIMs) was assessed. After ending the experiments, we further determined tyrosine hydroxylase (TH)-positive dopaminergic neurons number by immunohistochemistry, dopamine levels by HPLC, glial cell line-derived neurotrophic factor (GDNF) levels by ELISA, NR2B tyrosine phosphorylation and interactions of NR2B with Fyn by immunoblotting and immunoprecipitation. The results demonstrated that rTMS obviously attenuated AIMs scores, reduced the loss of nigral dopaminergic neurons and the fluctuations of striatal dopamine levels. Meanwhile, rTMS significantly increased the expression of GDNFwhich couldrestore the damage of dopaminergic neurons. Additionally, rTMS also reduced the levels of the NR2B tyrosine phosphorylation andits interactions with Fyn in the lesioned striatum of LID rats model. Thus, these data indicate that rTMS can provide benefit for the therapy of LID by improving the key biochemical deficits related to dyskinesia. PMID:27613848

  2. Cognitive and Anatomical Underpinnings of the Conceptual Knowledge for Common Objects and Familiar People: A Repetitive Transcranial Magnetic Stimulation Study

    PubMed Central

    Campanella, Fabio; Fabbro, Franco; Urgesi, Cosimo

    2013-01-01

    Several studies have addressed the issue of how knowledge of common objects is organized in the brain, whereas the cognitive and anatomical underpinnings of familiar people knowledge have been less explored. Here we applied repetitive transcranial magnetic stimulation (rTMS) over the left and right temporal poles before asking healthy individuals to perform a speeded word-to-picture matching task using familiar people and common objects as stimuli. We manipulated two widely used semantic variables, namely the semantic distance and the familiarity of stimuli, to assess whether the semantic organization of familiar people knowledge is similar to that of common objects. For both objects and faces we reliably found semantic distance and familiarity effects, with less accurate and slower responses for stimulus pairs that were more closely related and less familiar. However, the effects of semantic variables differed across categories, with semantic distance effects larger for objects and familiarity effects larger for faces, suggesting that objects and faces might share a partially comparable organization of their semantic representations. The application of rTMS to the left temporal pole modulated, for both categories, semantic distance, but not familiarity effects, revealing that accessing object and face concepts might rely on overlapping processes within left anterior temporal regions. Crucially, rTMS of the left temporal pole affected only the recognition of pairs of stimuli that could be discriminated at specific levels of categorization (e.g., two kitchen tools or two famous persons), with no effect for discriminations at either superordinate or individual levels. Conversely, rTMS of the right temporal pole induced an overall slowing of reaction times that positively correlated with the visual similarity of the stimuli, suggesting a more perceptual rather than semantic role of the right anterior temporal regions. Results are discussed in the light of current

  3. Dual-hemisphere repetitive transcranial magnetic stimulation for rehabilitation of poststroke aphasia: a randomized, double-blind clinical trial.

    PubMed

    Khedr, Eman M; Abo El-Fetoh, Noha; Ali, Anwer M; El-Hammady, Dina H; Khalifa, Hosam; Atta, Haisam; Karim, Ahmed A

    2014-10-01

    Recent neuroimaging studies on poststroke aphasia revealed maladaptive cortical changes in both hemispheres, yet their functional contribution in language recovery remains elusive. The aim of this study was to evaluate the long-term efficacy of dual-hemisphere repetitive transcranial magnetic stimulation (rTMS) on poststroke aphasia. Thirty patients with subacute poststroke nonfluent aphasia were randomly allocated to receive real or sham rTMS. Each patient received 1000 rTMS pulses (1 Hz at 110% of resting motor threshold [rMT] over the right unaffected Broca's area and 1000 pulses (20 Hz at 80% rMT) over the left affected Broca's area for 10 consecutive days followed by speech/language training. The language section of the Hemispheric Stroke Scale (HSS), the Stroke Aphasic Depression Questionnaire-Hospital Version (SADQ-H), and the National Institutes of Health Stroke Scale (NIHSS) were measured before, immediately after the 10 sessions, and 1 and 2 months after the last session. At baseline, there were no significant differences between groups in demographic and clinical rating scales. However, there was a significantly greater improvement in the HSS language score as well as in the SADQ-H after real rTMS compared with sham rTMS, which remained significant 2 months after the end of the treatment sessions. This is the first clinical study of dual-hemisphere rTMS in poststroke aphasia. Combining dual-hemisphere rTMS with language training might be a feasible treatment for nonfluent aphasia; further multicenter studies are needed to confirm this result. © The Author(s) 2014.

  4. Repetitive transcranial magnetic stimulation regulates L-type Ca(2+) channel activity inhibited by early sevoflurane exposure.

    PubMed

    Liu, Yang; Yang, Huiyun; Tang, Xiaohong; Bai, Wenwen; Wang, Guolin; Tian, Xin

    2016-09-01

    Sevoflurane might be harmful to the developing brain. Therefore, it is essential to reverse sevoflurane-induced brain injury. This study aimed to determine whether low-frequency repetitive transcranial magnetic stimulation (rTMS) can regulate L-type Ca(2+) channel activity, which is inhibited by early sevoflurane exposure. Rats were randomly divided into three groups: control, sevoflurane, and rTMS groups. A Whole-cell patch clamp technique was applied to record L-type Ca(2+) channel currents. The I-V curve, steady-state activation and inactivation curves were studied in rats of each group at different ages (1 week, 2 weeks, 3 weeks, 4 weeks and 5 weeks old). In the control group, L-type Ca(2+) channel current density significantly increased from week 2 to week 3. Compared with the control group, L-type Ca(2+) channel currents of rats in the sevoflurane group were significantly inhibited from week 1 to week 3. Activation curves of L-type Ca(2+) channel shifted significantly towards depolarization at week 1 and week 2. Moreover, steady-state inactivation curves shifted towards hyperpolarization from week 1 to week 3. Compared with the sevoflurane group, rTMS significantly increased L-type Ca(2+) channel currents at week 2 and week 3. Activation curves of L-type Ca(2+) channel significantly shifted towards hyperpolarization at week 2. Meanwhile, steady-state inactivation curves significantly shifted towards depolarization at week 2. The period between week 2 and week 3 is critical for the development of L-type Ca(2+) channels. Early sevoflurane exposure inhibits L-type Ca(2+) channel activity and rTMS can regulate L-type Ca(2+) channel activity inhibited by sevoflurane. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Evaluating the Effect of Repetitive Transcranial Magnetic Stimulation on Disorders of Consciousness by Using TMS-EEG.

    PubMed

    Bai, Yang; Xia, Xiaoyu; Kang, Jiannan; Yin, Xiaoxiao; Yang, Yi; He, Jianghong; Li, Xiaoli

    2016-01-01

    Background: The modulation efficacy of Transcranial magnetic stimulation (TMS) on consciousness improvement of patient with disorder of consciousness (DOC) has not been definitely confirmed. Objective: This study proposes TMS-EEG to assess effects of repetitive TMS (rTMS) on brain modulation of DOC. Methods: Twenty sessions of 10 Hz rTMS were applied over the dorsolateral prefrontal cortex for a patient with DOC. Measures of Coma Recovery Scale-Revised (CRS-R) score, TMS-evoked potential (TEP), perturbation complexity index (PCI), and global mean field power (GMFP) were used to evaluate the consciousness level of the patient at three intervals: before the rTMS protocol (T0), immediately after one session rTMS (T1), and immediately after 20 sessions (T2). Results: It was found that the patient was diagnosed of a minimally conscious state minus (MCS-) by means of CRS-R at the interval of T0, however the TEP and PCI indicated the patient was vegetative state (VS). At the interval of T1, there was not any clinical behavioral improvement in CRS-R, but we could find significant changes in TEP, PCI, and GMFP. At the interval of T2 there was a significant increase of consciousness level according by CRS-R score, PCI value, TEP, and GMFP after 20 sessions of 10 Hz rTMS on the patient with DOC. Conclusions: We demonstrated that TMS-EEG might be an efficient assessment tool for evaluating rTMS protocol therapeutic efficiency in DOC.

  6. The Role of Right Inferior Parietal Cortex in Auditory Spatial Attention: A Repetitive Transcranial Magnetic Stimulation Study

    PubMed Central

    Karhson, Debra S.; Mock, Jeffrey R.; Golob, Edward J.

    2015-01-01

    Behavioral studies support the concept of an auditory spatial attention gradient by demonstrating that attentional benefits progressively diminish as distance increases from an attended location. Damage to the right inferior parietal cortex can induce a rightward attention bias, which implicates this region in the construction of attention gradients. This study used event-related potentials (ERPs) to define attention-related gradients before and after repetitive transcranial magnetic stimulation (rTMS) to the right inferior parietal cortex. Subjects (n = 16) listened to noise bursts at five azimuth locations (left to right: -90°, -45°, 0° midline, +45°, +90°) and responded to stimuli at one target location (-90°, +90°, separate blocks). ERPs as a function of non-target location were examined before (baseline) and after 0.9 Hz rTMS. Results showed that ERP attention gradients were observed in three time windows (frontal 230–340, parietal 400–460, frontal 550–750 ms). Significant transient rTMS effects were seen in the first and third windows. The first window had a voltage decrease at the farthest location when attending to either the left or right side. The third window had on overall increase in positivity, but only when attending to the left side. These findings suggest that rTMS induced a small contraction in spatial attention gradients within the first time window. The asymmetric effect of attended location on gradients in the third time window may relate to neglect of the left hemispace after right parietal injury. Together, these results highlight the role of the right inferior parietal cortex in modulating frontal lobe attention network activity. PMID:26636333

  7. Anti-depressive mechanism of repetitive transcranial magnetic stimulation in rat: the role of the endocannabinoid system.

    PubMed

    Wang, Hua-ning; Wang, Lei; Zhang, Rui-guo; Chen, Yun-chun; Liu, Ling; Gao, Fang; Nie, Huang; Hou, Wu-gang; Peng, Zheng-wu; Tan, Qingrong

    2014-04-01

    Repetitive transcranial magnetic stimulation (rTMS) to treat depression has been thoroughly investigated in recent years. However, the underlying mechanisms are not fully understood. In this study, a chronic unpredictable mild stress (CUMS) paradigm was applied to male Sprague Dawley rats. Then rTMS was performed for 7 consecutive days, and the anti-depressive effects were evaluated by the sucrose preference test (SPT), the forced swimming test (FST), and the open-field test (OFT). Hippocampal cannabinoid type I receptor (CB1) expression was measured, and the expression levels of brain-derived neurotrophic factor (BDNF), Bcl-2, and Bax and the number of bromodeoxyuridine (BrdU)-positive cells were also investigated. These parameters were also observed after the selective CB1 receptor antagonist AM251 was used as a blocking agent. The results showed that CUMS induced a significant decrease in sucrose preference, a significant increase in immobility time in the FST, and a significantly decreased horizontal distance in the OFT. In addition, reduced hippocampal CB1 receptor, BDNF, and Bcl-2/Bax protein expression levels in CUMS rats, as well as decreased cell proliferation were also observed in the dentate gyrus. Meanwhile, rTMS treatment up-regulated cell proliferation; elevated CB1 receptor, BDNF, and Bcl-2/Bax expression levels in the hippocampus; and ameliorated depressive-like behaviors. All of these beneficial effects were abolished by AM251. These results indicate that rTMS increases BDNF production and hippocampal cell proliferation to protect against CUMS-induced changes through its effect on CB1 receptors. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Repetitive transcranial magnetic stimulation (rTMS) improves behavioral and biochemical deficits in levodopa-induced dyskinetic rats model.

    PubMed

    Ba, Maowen; Kong, Min; Guan, Lina; Yi, Maoli; Zhang, Hongli

    2016-09-13

    Fluctuations of dopamine levels and upregulations of NR2B tyrosine phosphorylation in the striatum have been connected with levodopa (L-dopa)-induced dyskinesia (LID) in Parkinson's disease (PD). Repetitive transcranial magnetic stimulation (rTMS) is one of the noninvasive and potential method treating dyskinesia. Yet, the effect of rTMS on the above key pathological events remains unclear. In this study, we gave L-dopa treatment intraperitoneally for 22 days to 6-hydroxydopamine-lesioned PD rats to prepare LID rats model, and subsequently applied rTMS daily for 3 weeks to LID rats model. The effect of rTMS on abnormal involuntary movements (AIMs) was assessed. After ending the experiments, we further determined tyrosine hydroxylase (TH)-positive dopaminergic neurons number by immunohistochemistry, dopamine levels by HPLC, glial cell line-derived neurotrophic factor (GDNF) levels by ELISA, NR2B tyrosine phosphorylation and interactions of NR2B with Fyn by immunoblotting and immunoprecipitation. The results demonstrated that rTMS obviously attenuated AIMs scores, reduced the loss of nigral dopaminergic neurons and the fluctuations of striatal dopamine levels. Meanwhile, rTMS significantly increased the expression of GDNF, which couldrestore the damage of dopaminergic neurons. Additionally, rTMS also reduced the levels of the NR2B tyrosine phosphorylation andits interactions with Fyn in the lesioned striatum of LID rats model. Thus, these data indicate that rTMS can provide benefit for the therapy of LID by improving the key biochemical deficits related to dyskinesia.

  9. Cyclical changes of cortical excitability and metaplasticity in migraine: evidence from a repetitive transcranial magnetic stimulation study.

    PubMed

    Cosentino, Giuseppe; Fierro, Brigida; Vigneri, Simone; Talamanca, Simona; Paladino, Piera; Baschi, Roberta; Indovino, Serena; Maccora, Simona; Valentino, Francesca; Fileccia, Enrico; Giglia, Giuseppe; Brighina, Filippo

    2014-06-01

    The primary brain dysfunctions leading to the onset of a migraine attack remain largely unknown. Other important open questions concern the mechanisms of initiation, continuation, and termination of migraine pain, and the changes in brain function underlying migraine transformation. Brief trains of high-frequency repetitive transcranial magnetic stimulation (rTMS), when applied to the primary motor cortex at suprathreshold intensity (⩾120% of resting motor threshold [RMT]), elicit in healthy subjects a progressive, glutamate-dependent facilitation of the motor evoked potentials (MEP). Conversely, in conditions of increased cortical excitability, the rTMS trains induce inhibitory MEP responses likely mediated by cortical homeostatic mechanisms. We enrolled 66 migraine-without-aura patients, 48 migraine-with-aura patients, 14 patients affected by chronic migraine (CM), and 20 healthy controls. We assessed motor cortical response to 5-Hz rTMS trains of 10 stimuli given at 120% RMT. Patients with episodic migraine were studied in different phases of the migraine cycle: interictal, preictal, ictal, and postictal states. Results showed a facilitatory MEP response during the trains in patients evaluated in the preictal phase, whereas inhibitory responses were observed during and after a migraine attack, as well as in CM patients. In the interictal phase, different responses were observed, depending on attack frequency: facilitation in patients with low and inhibition in those with high attack recurrence. Our findings suggest that changes in cortical excitability and fluctuations in the threshold for inhibitory metaplasticity underlie the migraine attack recurrence, and could be involved in the process of migraine transformation.

  10. Therapeutic impact of repetitive transcranial magnetic stimulation (rTMS) on tinnitus: a systematic review and meta-analysis.

    PubMed

    Soleimani, Robabeh; Jalali, Mir Mohammad; Hasandokht, Tolou

    2016-07-01

    In this study, we conducted a systematic literature review and meta-analysis on the effect of repetitive transcranial magnetic stimulation (rTMS) compared with sham in chronic tinnitus patients. We searched databases, from their onset up to August 2014, for randomized controlled trials (RCT) in English that assessed the effectiveness of rTMS for chronic tinnitus. RCTs were selected according to inclusion/exclusion criteria before data were extracted. For the meta-analysis weighted mean differences (and standard deviations) of Tinnitus Questionnaire (TQ) and Tinnitus Handicap Inventory (THI) scores were determined. Therapeutic success was defined as difference of at least 7 points in the THI score between baseline and the follow-up assessment after treatment. The odds ratio (OR) for this variable was assessed. Results from 15 RCTs were analyzed. The mean difference for TQ score at 1 week after intervention was 3.42. For THI, the data of mean difference score in two groups, 1 and 6 month after intervention, was 6.71 and 12.89, respectively. The all comparisons indicated a significant medium to large effect size in follow-up which is in favor of the rTMS. The pooled OR of therapeutic success of the studies which used THI at 1 month after intervention was 15.75. These data underscore the clinical effect of rTMS in the treatment of tinnitus. However, there is high variability of studies design and reported outcomes. Replication of data in multicenter trials with a large number of patients and long-term follow-up is needed before further conclusions can be drawn.

  11. Use of the Temperament and Character Inventory to Predict Response to Repetitive Transcranial Magnetic Stimulation for Major Depression

    PubMed Central

    Siddiqi, Shan H.; Chockalingam, Ravikumar; Cloninger, C. Robert; Lenze, Eric J.; Cristancho, Pilar

    2016-01-01

    Objective . The goal of this study was to investigate the utility of the Temperament and Character Inventory (TCI) in predicting antidepressant response to repetitive transcranial magnetic stimulation (rTMS). Background Although rTMS of the dorsolateral prefrontal cortex (DLPFC) is an established antidepressant treatment, little is known about predictors of response. The TCI measures multiple personality dimensions (harm avoidance, novelty seeking, reward dependence, persistence, self-directedness, self-transcendence, and cooperativeness), some of which have predicted response to pharmacotherapy and cognitive-behavioral therapy. A previous study suggested a possible association between self-directedness and response to rTMS in melancholic depression, although this was limited by the fact that melancholic depression is associated with a limited range of TCI profiles. Methods . Nineteen patients with a major depressive episode completed the TCI prior to a clinical course of rTMS over the DLPFC. Treatment response was defined as ≥50% decrease in scores on the Hamilton Rating Scale for Depression (HAM-D). Baseline scores on each TCI dimension were compared between responders and non-responders via analysis of variance. Pearson correlations were also calculated for temperament/character scores in comparison with percentage improvement in HAM-D scores. Results Eleven of the 19 patients responded to rTMS. T-scores for persistence were significantly higher in responders than in non-responders (P=0.022). Linear regression revealed a correlation between persistence scores and percentage improvement in HAM-D scores. Conclusions Higher persistence scores predicted antidepressant response to rTMS. This may be explained by rTMS-induced enhancement of cortical excitability, which has been found to be decreased in patients with high persistence. Personality assessment that includes measurement of TCI persistence may be a useful component of precision medicine initiatives in r

  12. Use of the Temperament and Character Inventory to Predict Response to Repetitive Transcranial Magnetic Stimulation for Major Depression.

    PubMed

    Siddiqi, Shan H; Chockalingam, Ravikumar; Cloninger, C Robert; Lenze, Eric J; Cristancho, Pilar

    2016-05-01

    The goal of this study was to investigate the utility of the Temperament and Character Inventory (TCI) in predicting antidepressant response to repetitive transcranial magnetic stimulation (rTMS). Although rTMS of the dorsolateral prefrontal cortex is an established antidepressant treatment, little is known about predictors of response. The TCI measures multiple personality dimensions (harm avoidance, novelty seeking, reward dependence, persistence, self-directedness, self-transcendence, and cooperativeness), some of which have predicted response to pharmacotherapy and cognitive-behavioral therapy. A previous study suggested a possible association between self-directedness and response to rTMS in melancholic depression, although this was limited by the fact that melancholic depression is associated with a limited range of TCI profiles. Nineteen patients with a major depressive episode completed the TCI before a clinical course of rTMS over the dorsolateral prefrontal cortex. Treatment response was defined as ≥50% decrease in scores on the Hamilton Rating Scale for Depression (Ham-D). Baseline scores on each TCI dimension were compared between responders and nonresponders through analysis of variance. Pearson correlations were also calculated for temperament/character scores in comparison with percentage improvement in Ham-D scores. Eleven of the 19 patients responded to rTMS. T-scores for persistence were significantly higher in responders than in nonresponders (P=0.022). Linear regression revealed a correlation between persistence scores and percentage improvement in Ham-D scores. Higher persistence scores predicted antidepressant response to rTMS. This may be explained by rTMS-induced enhancement of cortical excitability, which has been found to be decreased in patients with high persistence. Personality assessment that includes measurement of TCI persistence may be a useful component of precision medicine initiatives in rTMS for depression.

  13. Evaluating the Effect of Repetitive Transcranial Magnetic Stimulation on Disorders of Consciousness by Using TMS-EEG

    PubMed Central

    Bai, Yang; Xia, Xiaoyu; Kang, Jiannan; Yin, Xiaoxiao; Yang, Yi; He, Jianghong; Li, Xiaoli

    2016-01-01

    Background: The modulation efficacy of Transcranial magnetic stimulation (TMS) on consciousness improvement of patient with disorder of consciousness (DOC) has not been definitely confirmed. Objective: This study proposes TMS-EEG to assess effects of repetitive TMS (rTMS) on brain modulation of DOC. Methods: Twenty sessions of 10 Hz rTMS were applied over the dorsolateral prefrontal cortex for a patient with DOC. Measures of Coma Recovery Scale-Revised (CRS-R) score, TMS-evoked potential (TEP), perturbation complexity index (PCI), and global mean field power (GMFP) were used to evaluate the consciousness level of the patient at three intervals: before the rTMS protocol (T0), immediately after one session rTMS (T1), and immediately after 20 sessions (T2). Results: It was found that the patient was diagnosed of a minimally conscious state minus (MCS-) by means of CRS-R at the interval of T0, however the TEP and PCI indicated the patient was vegetative state (VS). At the interval of T1, there was not any clinical behavioral improvement in CRS-R, but we could find significant changes in TEP, PCI, and GMFP. At the interval of T2 there was a significant increase of consciousness level according by CRS-R score, PCI value, TEP, and GMFP after 20 sessions of 10 Hz rTMS on the patient with DOC. Conclusions: We demonstrated that TMS-EEG might be an efficient assessment tool for evaluating rTMS protocol therapeutic efficiency in DOC. PMID:27812319

  14. Time-resolved three-dimensional pulmonary MR angiography and perfusion imaging with ultrashort repetition time.

    PubMed

    Carr, James C; Laub, Gerhard; Zheng, Jie; Pereles, F Scott; Finn, J Paul

    2002-12-01

    The purpose of this study was to implement ultrafast, multiphase three-dimensional (3D) magnetic resonance (MR) angiography and perfusion imaging after bolus injection of contrast medium to generate preliminary validation of parameters in a pig model and to illustrate potential applications in patients with lung abnormalities. Five healthy volunteers, five patients, and three pigs underwent rapid, time-resolved pulmonary MR angiography and perfusion imaging on a 1.5-T MR imager. All patients had undergone correlative computed tomographic or conventional angiography. The pulse sequence was a 3D spin-warp, gradient-echo acquisition with a repetition time of 1.6 msec and an echo time of 0.6 msec. Each 3D acquisition lasted 2-3 seconds, and 8-16 sequential measurements were made in each study. Artificial pulmonary emboli were generated in pigs with gelatin sponge. All patients had diseases of the pulmonary circulation (as confirmed with other studies). Multiphasic, time-resolved pulmonary parenchymal enhancement was demonstrated in all healthy subjects and animals. All segmental (n = 100) and subsegmental (n = 200) branches were identified in the healthy subjects. Perfusion deficits were clearly demonstrated in all pigs after gelatin embolization. Perfusion defects were identified in two patients with lung disease. Abnormalities of the pulmonary vasculature were clearly identified in the patient group. Dynamic time-resolved 3D pulmonary MR angiography and perfusion imaging is feasible in humans as well as in animals. Induced perfusion deficits are identifiable after artificial embolization in pigs. Combined pulmonary MR angiography and parenchymal (perfusion) imaging may improve evaluation of the pulmonary circulation in a variety of conditions.

  15. Repetitive Transcranial Magnetic Stimulation (rTMS) in the Management of Alcohol Dependence and other Substance Abuse Disorders – Emerging Data and Clinical Relevance

    PubMed Central

    Sousa, Avinash De

    2013-01-01

    Repetitive transcranial magnetic stimulation (rTMS) has been used widely in various psychiatric disorders like depression and schizophrenia. There have been some reports of its usefulness in alcohol dependence and substance use disorders. The present paper reviews the studies done using rTMS in substance use disorders including alcohol and nicotine dependence. Various studies done have been reviewed including the proposed mechanisms of action are outlined with the future research needs and need for further clinical data PMID:25337357

  16. Low-intensity repetitive magnetic stimulation lowers action potential threshold and increases spike firing in layer 5 pyramidal neurons in vitro.

    PubMed

    Tang, Alexander D; Hong, Ivan; Boddington, Laura J; Garrett, Andrew R; Etherington, Sarah; Reynolds, John N J; Rodger, Jennifer

    2016-10-29

    Repetitive transcranial magnetic stimulation (rTMS) has become a popular method of modulating neural plasticity in humans. Clinically, rTMS is delivered at high intensities to modulate neuronal excitability. While the high-intensity magnetic field can be targeted to stimulate specific cortical regions, areas adjacent to the targeted area receive stimulation at a lower intensity and may contribute to the overall plasticity induced by rTMS. We have previously shown that low-intensity rTMS induces molecular and structural plasticity in vivo, but the effects on membrane properties and neural excitability have not been investigated. Here we investigated the acute effect of low-intensity repetitive magnetic stimulation (LI-rMS) on neuronal excitability and potential changes on the passive and active electrophysiological properties of layer 5 pyramidal neurons in vitro. Whole-cell current clamp recordings were made at baseline prior to subthreshold LI-rMS (600 pulses of iTBS, n=9 cells from 7 animals) or sham (n=10 cells from 9 animals), immediately after stimulation, as well as 10 and 20min post-stimulation. Our results show that LI-rMS does not alter passive membrane properties (resting membrane potential and input resistance) but hyperpolarises action potential threshold and increases evoked spike-firing frequency. Increases in spike firing frequency were present throughout the 20min post-stimulation whereas action potential (AP) threshold hyperpolarization was present immediately after stimulation and at 20min post-stimulation. These results provide evidence that LI-rMS alters neuronal excitability of excitatory neurons. We suggest that regions outside the targeted region of high-intensity rTMS are susceptible to neuromodulation and may contribute to rTMS-induced plasticity. Copyright © 2016 IBRO. All rights reserved.

  17. Growth hormone stimulation test - series (image)

    MedlinePlus

    ... skeletal growth in children. In adults, GH stimulates protein synthesis in muscle and the release of fatty acids ... acids. The amino acids are used in the synthesis of proteins, and the muscle shifts to using fatty acids ...

  18. Imaging distributed and massed repetitions of natural scenes: Spontaneous retrieval and maintenance

    PubMed Central

    Bradley, Margaret M.; Costa, Vincent D.; Ferrari, Vera; Codispoti, Maurizio; Fitzsimmons, Jeffrey R.; Lang, Peter J.

    2015-01-01

    Repetitions that are distributed (spaced) across time prompt enhancement of a memory-related event-related potential, compared to when repetitions are massed (contiguous). Here, we employed fMRI to investigate neural enhancement and suppression effects during free viewing of natural scenes that were either novel or repeated four times with massed or distributed repetitions. Distributed repetition was uniquely associated with a repetition enhancement effect in a bilateral posterior parietal cluster that included the precuneus and posterior cingulate and which has previously been implicated in episodic memory retrieval. Unique to massed repetition, on the other hand, was enhancement in a right dorsolateral prefrontal cluster that has been implicated in short-term maintenance. Repetition suppression effects for both types of spacing were widespread in regions activated during novel picture processing. Taken together, the data are consistent with a hypothesis that distributed repetition prompts spontaneous retrieval of prior occurrences, whereas massed repetitions prompts short-term maintenance of the episodic representation, due to contiguous presentation. These processing differences may mediate the classic spacing effect in learning and memory. PMID:25504854

  19. 1 Hz repetitive transcranial magnetic stimulation over dorsal premotor cortex enhances offline motor memory consolidation for sequence-specific implicit learning

    PubMed Central

    Meehan, S.K.; Zabukovec, J.R.; Dao, E.; Cheung, K.L.; Linsdell, M.A.; Boyd, L.A.

    2016-01-01

    Consolidation of motor memories associated with skilled practice can occur both online, concurrent with practice, and offline, after practice has ended. The current study investigated the role of dorsal premotor cortex (PMd) in early offline motor memory consolidation of implicit sequence specific learning. Thirty-three participants were assigned to one of three groups of repetitive TMS over left PMd (5 Hz, 1 Hz or control) immediately following practice of a novel continuous tracking task. There was no additional practice following repetitive TMS. This procedure was repeated for 4 days. The continuous tracking task contained a repeated sequence that could be learned implicitly and random sequences that could not. On a separate fifth day, a retention test was performed to assess implicit sequence-specific motor learning of the task. Tracking error was decreased for the group who received 1 Hz repetitive TMS over the PMd during the early consolidation period immediately following practice compared to control or 5 Hz repetitive TMS. Enhanced sequence specific learning with 1 Hz repetitive TMS following practice was due to greater offline consolidation, not differences in online learning between the groups within practice days. A follow-up experiment revealed that stimulation of PMd following practice did not differentially change motor cortical excitability, suggesting that changes in offline consolidation can be largely attributed to stimulation induced changes in PMd. These findings support a differential role for the PMd in support of online and offline sequence specific learning of a visuomotor task and offer converging evidence for competing memory systems. PMID:23834742

  20. Economic evaluation of resistant major depressive disorder treatment in Iranian population: a comparison between repetitive Transcranial Magnetic Stimulation with electroconvulsive

    PubMed Central

    Ghiasvand, Hesam; Moradi- Joo, Mohammad; Abolhassani, Nazanin; Ravaghi, Hamid; Raygani, Seyed Mansoor; Mohabbat-Bahar, Sahar

    2016-01-01

    Background: It is estimated that major depression disorders constitute 8.2% of years lived with disability (YLDs) globally. The repetitive Transcranial Magnetic Stimulation (rTMS) and Electroconvulsive Therapy (ECT) are two relative common interventions to treat major depressive disorders, especially for treatment resistant depression. In this study the cost- effectiveness and cost-utility of rTMS were compared with ECT in Iranian population suffering from major depressive disorder using a decision tree model. Methods: A decision tree model conducted to compare the cost-effectiveness ratio of rTMS with ECT in a health system prospective and 7 months’ time horizon. The outcome variables were: response rate, remission rate and quality-adjusted life-years (QALYs) of the rTMS and ECT as primary and secondary outcomes extracted from systematic reviews and randomized control trials. The costs were also calculated through a field study in one clinic and one hospital; the direct costs have only been considered. Results: The total cost for rTMS and ECTstrategieswere11015000Rials (373US$) and 11742700 Rials (397.7US$), respectively. Also the rTMS/ECT ratio of costs per improved patients was 1194410Rials (40.5 US$); the ratio for costs per QALYs utility was 21017139 Rials (711.72 US$). The incremental cost- effectiveness ratio of rTMS versus ECT was 1194410 Rials (40.44 US$) after treatment and maintenance courses. Conclusion: Given the current prevalence of depressive disorders in Iranian population, the ECT is more cost-effective than TMS. The sensitivity analysis showed that if the prevalence of major depressive disorders declines to below 5% or the costs of rTMS decrease (rTMS provided by public sector), then the rTMS becomes more cost-effective compared with ECT. However, efficacy of rTMS depends on the frequency of pulsed magnetic field, the location of rTMS on the head, the number of therapeutic sessions and the length of each session. PMID:27390700

  1. Efficacy Towards Negative Symptoms and Safety of Repetitive Transcranial Magnetic Stimulation Treatment for Patients with Schizophrenia: A Systematic Review

    PubMed Central

    WANG, Junjie; ZHOU, Yingqun; GAN, Hong; PANG, Jiaoyan; LI, Hui; WANG, Jijun; LI, Chunbo

    2017-01-01

    Background Negative symptoms are one of the most difficult areas in the treatment of schizophrenia because antipsychotics are often less effective towards them. Repetitive transcranial magnetic stimulation (rTMS) is a new technique for cerebral cortex stimulation and is believed to be a safe and promising method for the treatment of mental disorders. As the clinical research and new treatment models have increased in recent years, the efficacy towards negative symptoms and safety evaluation of rTMS treatment should also be updated. Aims To explore the efficacy and safety of rTMS in the treatment of negative symptoms for patients with schizophrenia. Methods We searched for relevant controlled clinical trials from the following databases: PubMed, EMBASE, the Cochrane Library, EBSCO, Web of Science, China National Knowledge Infrastructure (CNKI), VIP, Wanfang Data, SINOMED, and Airiti Library. The retrieval time went up to January 2, 2017. The research literature was screened according to the predefined inclusion and exclusion criteria. After data extraction, statistical analysis was conducted by using RevMan 5.3 and Stata 14. Quality evaluation was done on the included research articles. The Cochrane risk of bias assessment tool was adopted for assessing risk of bias. The GRADE (Grades of Recommendation, Assessment, Development, and Evaluation) system recommendation grading method was used as the reference standard. Results A total of 3500 articles were retrieved. In the end, there were 29 articles included in the metaanalysis with a total sample size of 1440. After the meta-analysis, it was found that the use of antipsychotic treatment combined with rTMS could improve the negative symptoms of patients (SMD=-0.40, 95% CI= -0.62~-0.18). Based on the bias of the efficacy evaluation assessed by the Cochrane risk of bias assessment tool, there were 6 studies rated as having “high risk of bias” and the rest were rated as “unable to determine”. According to the

  2. Two-photon laser-scanning microscopy for single and repetitive imaging of dorsal and lateral spinal white matter in vivo.

    PubMed

    Nadrigny, F; Le Meur, K; Steffens, H; Schomburg, E D; Safavi-Abbasi, S; Dibaj, P

    2017-02-28

    We developed appropriate surgical procedures for single and repetitive multi-photon imaging of spinal cord in vivo. By intravenous anesthesia, artificial ventilation and laminectomy, acute experiments were performed in the dorsal and lateral white matter. By volatile anesthesia and minimal-invasive surgery, chronic repetitive imaging up to 8 months were performed in the dorsal column through the window between two adjacent spines. Transgenic mouse technology enabled simultaneous imaging of labeled axons, astrocytes and microglia. Repetitive imaging showed positional shifts of microglia over time. These techniques serve for investigations of cellular dynamics and cell-cell interactions in intact and pathologically changed spinal tissue.

  3. Shaped magnetic field pulses by multi-coil repetitive transcranial magnetic stimulation (rTMS) differentially modulate anterior cingulate cortex responses and pain in volunteers and fibromyalgia patients

    PubMed Central

    2013-01-01

    Background Repetitive transcranial magnetic stimulation (rTMS) has shown promise in the alleviation of acute and chronic pain by altering the activity of cortical areas involved in pain sensation. However, current single-coil rTMS technology only allows for effects in surface cortical structures. The ability to affect activity in certain deep brain structures may however, allow for a better efficacy, safety, and tolerability. This study used PET imaging to determine whether a novel multi-coil rTMS would allow for preferential targeting of the dorsal anterior cingulate cortex (dACC), an area always activated with pain, and to provide preliminary evidence as to whether this targeted approach would allow for efficacious, safe, and tolerable analgesia both in a volunteer/acute pain model as well as in fibromyalgia chronic pain patients. Methods Part 1: Different coil configurations were tested in a placebo-controlled crossover design in volunteers (N = 16). Tonic pain was induced using a capsaicin/thermal pain model and functional brain imaging was performed by means of H215O positron emission tomography – computed tomography (PET/CT) scans. Differences in NRS pain ratings between TMS and sham treatment (NRSTMS-NRSplacebo) which were recorded each minute during the 10 minute PET scans. Part 2: 16 fibromyalgia patients were subjected to 20 multi-coil rTMS treatments over 4 weeks and effects on standard pain scales (Brief Pain Inventory, item 5, i.e. average pain NRS over the last 24 hours) were recorded. Results A single 30 minute session using one of 3 tested rTMS coil configurations operated at 1 Hz consistently produced robust reduction (mean 70% on NRS scale) in evoked pain in volunteers. In fibromyalgia patients, the 20 rTMS sessions also produced a significant pain inhibition (43% reduction in NRS pain over last 24 hours), but only when operated at 10 Hz. This degree of pain control was maintained for at least 4 weeks after the final session

  4. Shaped magnetic field pulses by multi-coil repetitive transcranial magnetic stimulation (rTMS) differentially modulate anterior cingulate cortex responses and pain in volunteers and fibromyalgia patients.

    PubMed

    Tzabazis, Alexander; Aparici, Carina Mari; Rowbotham, Michael C; Schneider, M Bret; Etkin, Amit; Yeomans, David C

    2013-07-02

    Repetitive transcranial magnetic stimulation (rTMS) has shown promise in the alleviation of acute and chronic pain by altering the activity of cortical areas involved in pain sensation. However, current single-coil rTMS technology only allows for effects in surface cortical structures. The ability to affect activity in certain deep brain structures may however, allow for a better efficacy, safety, and tolerability. This study used PET imaging to determine whether a novel multi-coil rTMS would allow for preferential targeting of the dorsal anterior cingulate cortex (dACC), an area always activated with pain, and to provide preliminary evidence as to whether this targeted approach would allow for efficacious, safe, and tolerable analgesia both in a volunteer/acute pain model as well as in fibromyalgia chronic pain patients. Part 1: Different coil configurations were tested in a placebo-controlled crossover design in volunteers (N = 16). Tonic pain was induced using a capsaicin/thermal pain model and functional brain imaging was performed by means of H2(15)O positron emission tomography - computed tomography (PET/CT) scans. Differences in NRS pain ratings between TMS and sham treatment (NRS(TMS)-NRS(placebo)) which were recorded each minute during the 10 minute PET scans. Part 2: 16 fibromyalgia patients were subjected to 20 multi-coil rTMS treatments over 4 weeks and effects on standard pain scales (Brief Pain Inventory, item 5, i.e. average pain NRS over the last 24 hours) were recorded. A single 30 minute session using one of 3 tested rTMS coil configurations operated at 1 Hz consistently produced robust reduction (mean 70% on NRS scale) in evoked pain in volunteers. In fibromyalgia patients, the 20 rTMS sessions also produced a significant pain inhibition (43% reduction in NRS pain over last 24 hours), but only when operated at 10 Hz. This degree of pain control was maintained for at least 4 weeks after the final session. Multi-coil rTMS may be a safe and

  5. Effects of repetitive pulsing on multi-kHz planar laser-induced incandescence imaging in laminar and turbulent flames.

    PubMed

    Michael, James B; Venkateswaran, Prabhakar; Shaddix, Christopher R; Meyer, Terrence R

    2015-04-10

    Planar laser-induced incandescence (LII) imaging is reported at repetition rates up to 100 kHz using a burst-mode laser system to enable studies of soot formation dynamics in highly turbulent flames. To quantify the accuracy and uncertainty of relative soot volume fraction measurements, the temporal evolution of the LII field in laminar and turbulent flames is examined at various laser operating conditions. Under high-speed repetitive probing, it is found that LII signals are sensitive to changes in soot physical characteristics when operating at high laser fluences within the soot vaporization regime. For these laser conditions, strong planar LII signals are observed at measurement rates up to 100 kHz but are primarily useful for qualitative tracking of soot structure dynamics. However, LII signals collected at lower fluences allow sequential planar measurements of the relative soot volume fraction with a sufficient signal-to-noise ratio at repetition rates of 10-50 kHz. Guidelines for identifying and avoiding the onset of repetitive probe effects in the LII signals are discussed, along with other potential sources of measurement error and uncertainty.

  6. Effects of repetitive pulsing on multi-kHz planar laser-induced incandescence imaging in laminar and turbulent flames

    DOE PAGES

    Michael, James B.; Venkateswaran, Prabhakar; Shaddix, Christopher R.; ...

    2015-04-08

    Planar laser-induced incandescence (LII) imaging is reported at repetition rates up to 100 kHz using a burst-mode laser system to enable studies of soot formation dynamics in highly turbulent flames. Furthermore, to quantify the accuracy and uncertainty of relative soot volume fraction measurements, the temporal evolution of the LII field in laminar and turbulent flames is examined at various laser operating conditions. Under high-speed repetitive probing, it is found that LII signals are sensitive to changes in soot physical characteristics when operating at high laser fluences within the soot vaporization regime. For these laser conditions, strong planar LII signals aremore » observed at measurement rates up to 100 kHz but are primarily useful for qualitative tracking of soot structure dynamics. However, LII signals collected at lower fluences allow sequential planar measurements of the relative soot volume fraction with a sufficient signal-to-noise ratio at repetition rates of 10–50 kHz. Finally, guidelines for identifying and avoiding the onset of repetitive probe effects in the LII signals are discussed, along with other potential sources of measurement error and uncertainty.« less

  7. Effects of repetitive pulsing on multi-kHz planar laser-induced incandescence imaging in laminar and turbulent flames

    SciTech Connect

    Michael, James B.; Venkateswaran, Prabhakar; Shaddix, Christopher R.; Meyer, Terrence R.

    2015-04-08

    Planar laser-induced incandescence (LII) imaging is reported at repetition rates up to 100 kHz using a burst-mode laser system to enable studies of soot formation dynamics in highly turbulent flames. Furthermore, to quantify the accuracy and uncertainty of relative soot volume fraction measurements, the temporal evolution of the LII field in laminar and turbulent flames is examined at various laser operating conditions. Under high-speed repetitive probing, it is found that LII signals are sensitive to changes in soot physical characteristics when operating at high laser fluences within the soot vaporization regime. For these laser conditions, strong planar LII signals are observed at measurement rates up to 100 kHz but are primarily useful for qualitative tracking of soot structure dynamics. However, LII signals collected at lower fluences allow sequential planar measurements of the relative soot volume fraction with a sufficient signal-to-noise ratio at repetition rates of 10–50 kHz. Finally, guidelines for identifying and avoiding the onset of repetitive probe effects in the LII signals are discussed, along with other potential sources of measurement error and uncertainty.

  8. Dental caries imaging using hyperspectral stimulated Raman scattering microscopy

    NASA Astrophysics Data System (ADS)

    Wang, Zi; Zheng, Wei; Jian, Lin; Huang, Zhiwei

    2016-03-01

    We report the development of a polarization-resolved hyperspectral stimulated Raman scattering (SRS) imaging technique based on a picosecond (ps) laser-pumped optical parametric oscillator system for label-free imaging of dental caries. In our imaging system, hyperspectral SRS images (512×512 pixels) in both fingerprint region (800-1800 cm-1) and high-wavenumber region (2800-3600 cm-1) are acquired in minutes by scanning the wavelength of OPO output, which is a thousand times faster than conventional confocal micro Raman imaging. SRS spectra variations from normal enamel to caries obtained from the hyperspectral SRS images show the loss of phosphate and carbonate in the carious region. While polarization-resolved SRS images at 959 cm-1 demonstrate that the caries has higher depolarization ratio. Our results demonstrate that the polarization resolved-hyperspectral SRS imaging technique developed allows for rapid identification of the biochemical and structural changes of dental caries.

  9. High-frequency repetitive transcranial magnetic stimulation over the hand area of the primary motor cortex disturbs predictive grip force scaling.

    PubMed

    Nowak, Dennis A; Voss, Martin; Huang, Ying-Zu; Wolpert, Daniel M; Rothwell, John C

    2005-11-01

    When we repetitively lift an object, our grip force is influenced by the mechanical object properties of the preceding lift, irrespective of whether the subsequent lift is performed with the same hand or the hand opposite to the preceding lift. This study investigates if repetitive high-frequency transcranial magnetic stimulation (rTMS) over the dominant primary motor cortex affects this relationship. After completion of 10 lifts of an object using the dominant hand, rTMS was applied over the dominant primary motor cortex for 20 s. On the first lift following rTMS, the peak grip force was significantly higher than on the lift preceding rTMS. Moreover, this measure remained elevated throughout the following set of lifts after rTMS. rTMS did not change the peak lift force generated by more proximal arm muscles. The same effect was observed when the lifts following rTMS over the dominant motor cortex were performed with the ipsilateral hand. These effects were not observed when subjects rested both hands on their lap or when a sham stimulation was applied for the same period of time. These preliminary data suggest that rTMS over the sensorimotor cortex disturbs predictive grip force planning.

  10. Effects of low-frequency repetitive transcranial magnetic stimulation combined with intensive speech therapy on cerebral blood flow in post-stroke aphasia.

    PubMed

    Hara, Takatoshi; Abo, Masahiro; Kobayashi, Kentaro; Watanabe, Motoi; Kakuda, Wataru; Senoo, Atushi

    2015-10-01

    We provided an intervention to chronic post-stroke aphasic patients using low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) guided by a functional magnetic resonance imaging (fMRI) evaluation of language laterality, combined with intensive speech therapy (ST). We performed a single photon emission-computed tomography (SPECT) scan pre- and post-intervention and investigated the relationship between cerebral blood flow (CBF) and language function. Fifty right-handed chronic post-stroke aphasic patients were enrolled in the study. During their 11-day hospital admission, the patients received a 40-min session of 1-Hz LF-rTMS on the left or right hemisphere, according to language localization identified by the fMRI evaluation, and intensive ST daily for 10 days, except for Sunday. A SPECT scan and language evaluation by the Standard Language Test of Aphasia (SLTA) were performed at the time of admission and at 3 months following discharge. We calculated laterality indices (LIs) of regional CBF (rCBF) in 13 language-related Brodmann area (BA) regions of interest. In patients who received LF-rTMS to the intact right hemisphere (RH-LF-rTMS), the improvement in the total SLTA score was significantly correlated with the pre- and post-intervention change of LI (ΔLI) in BA44. In patients who received LF-rTMS to the lesional left hemisphere (LH-LF-rTMS), this association was not observed. Analyses of the SLTA subscales and rCBF ΔLI demonstrated that in the RH-LF-rTMS group, the SLTA Speaking subscale scores were significantly correlated with ΔLIs in BA11, 20, and 21, and the SLTA Writing subscale scores were significantly correlated with ΔLIs in BA6 and 39. Conversely, in the LH-LF-rTMS group, the SLTA Speaking subscale scores were correlated with ΔLI in BA10, and the SLTA Reading subscale scores were significantly correlated with ΔLIs in BA13, 20, 22, and 44. Our results suggest the possibility that fMRI-guided LF-rTMS combined with intensive ST may

  11. Treatment of Alice in Wonderland syndrome and verbal auditory hallucinations using repetitive transcranial magnetic stimulation: a case report with fMRI findings.

    PubMed

    Blom, Jan Dirk; Looijestijn, Jasper; Goekoop, Rutger; Diederen, Kelly M J; Rijkaart, Anne-Marije; Slotema, Christina W; Sommer, Iris E C

    2011-01-01

    Alice in Wonderland syndrome (AIWS) is a rare cluster of CNS symptoms characterized by visual distortions (i.e. metamorphopsias), body image distortions, time distortions, and déjà experiences. Verbal auditory hallucinations (VAHs) are the most prevalent type of hallucination in adults with or without a history of psychiatric illness. Here, we report the case of a woman with AIWS, long-lasting VAHs, and various additional perceptual and mood symptoms. Semi-structured interviews were used to assess symptoms, and functional MRI (fMRI) was employed to localize cerebral activity during self-reported VAHs. Treatment consisted of repetitive transcranial magnetic stimulation (rTMS) at a frequency of 1 Hz at T3P3, overlying Brodmann's area 40. Activation during VAHs was observed bilaterally in the basal ganglia, the primary auditory cortex, the association auditory cortex, the temporal poles, and the anterior cingulated gyrus. The left and right inferior frontal gyri (Broca's area and its contralateral homologue) were involved, along with the dorsolateral prefrontal cortex. Interestingly, synchronized activation was observed in the primary visual cortex (areas V1 and V2), and the bilateral dorsal visual cortex. The higher visual association cortex also showed significant, but less prominent, activation. During the second week of rTMS treatment, not only the VAHs, but also the other sensory deceptions/distortions and mood symptoms showed complete remission. The patient remained free of any symptoms during a 4-month follow-up phase. After 8 months, when many of the original symptoms had returned, a second treatment phase with rTMS was again followed by complete remission. This case indicates that VAHs and metamorphopsias in AIWS are associated with synchronized activation in both auditory and visual cortices. It also indicates that local rTMS treatment may have global therapeutic effects, suggesting an effect on multiple brain regions in a distributed network. Although a

  12. Volumetric chemical imaging by stimulated Raman projection microscopy and tomography

    PubMed Central

    Chen, Xueli; Zhang, Chi; Lin, Peng; Huang, Kai-Chih; Liang, Jimin; Tian, Jie; Cheng, Ji-Xin

    2017-01-01

    Volumetric imaging allows global understanding of three-dimensional (3D) complex systems. Light-sheet fluorescence microscopy and optical projection tomography have been reported to image 3D volumes with high resolutions and at high speeds. Such methods, however, usually rely on fluorescent labels for chemical targeting, which could perturb the biological functionality in living systems. We demonstrate Bessel-beam-based stimulated Raman projection (SRP) microscopy and tomography for label-free volumetric chemical imaging. Our SRP microscope enables fast quantitation of chemicals in a 3D volume through a two-dimensional lateral scan. Furthermore, combining SRP and sample rotation, we demonstrate the SRP tomography that can reconstruct the 3D distribution of chemical compositions with optical spatial resolution at a higher speed than the Gaussian-beam-based stimulated Raman scattering sectioning imaging can. We explore the potential of our SRP technology by mapping polymer particles in 3D volumes and lipid droplets in adipose cells. PMID:28436473

  13. Volumetric chemical imaging by stimulated Raman projection microscopy and tomography

    NASA Astrophysics Data System (ADS)

    Chen, Xueli; Zhang, Chi; Lin, Peng; Huang, Kai-Chih; Liang, Jimin; Tian, Jie; Cheng, Ji-Xin

    2017-04-01

    Volumetric imaging allows global understanding of three-dimensional (3D) complex systems. Light-sheet fluorescence microscopy and optical projection tomography have been reported to image 3D volumes with high resolutions and at high speeds. Such methods, however, usually rely on fluorescent labels for chemical targeting, which could perturb the biological functionality in living systems. We demonstrate Bessel-beam-based stimulated Raman projection (SRP) microscopy and tomography for label-free volumetric chemical imaging. Our SRP microscope enables fast quantitation of chemicals in a 3D volume through a two-dimensional lateral scan. Furthermore, combining SRP and sample rotation, we demonstrate the SRP tomography that can reconstruct the 3D distribution of chemical compositions with optical spatial resolution at a higher speed than the Gaussian-beam-based stimulated Raman scattering sectioning imaging can. We explore the potential of our SRP technology by mapping polymer particles in 3D volumes and lipid droplets in adipose cells.

  14. Multimodal imaging of repetition priming: Using fMRI, MEG, and intracranial EEG to reveal spatiotemporal profiles of word processing

    PubMed Central

    McDonald, Carrie R.; Thesen, Thomas; Carlson, Chad; Blumberg, Mark; Girard, Holly M.; Trongnetrpunya, Amy; Sherfey, Jason S.; Devinsky, Orrin; Kuzniecky, Rubin; Dolye, Werner K.; Cash, Sydney S.; Leonard, Matt K.; Hagler, Donald J.; Dale, Anders M.; Halgren, Eric

    2010-01-01

    Repetition priming is a core feature of memory processing whose anatomical correlates remain poorly understood. In this study, we use advanced multimodal imaging (functional magnetic resonance imaging (fMRI) and magnetoencephalography; MEG) to investigate the spatiotemporal profile of repetition priming. We use intracranial electroencephalography (iEEG) to validate our fMRI/MEG measurements. Twelve controls completed a semantic judgment task with fMRI and MEG that included words presented once (new, ‘N’) and words that repeated (old, ‘O’). Six patients with epilepsy completed the same task during iEEG recordings. Blood-oxygen level dependent (BOLD) responses for N vs O words were examined across the cortical surface and within regions of interest. MEG waveforms for N vs O words were estimated using a noise-normalized minimum norm solution, and used to interpret the timecourse of fMRI. Spatial concordance was observed between fMRI and MEG repetition effects from 350–450ms within bilateral occipitotemporal and medial temporal, left prefrontal, and left posterior temporal cortex. Additionally, MEG revealed widespread sources within left temporoparietal regions, whereas fMRI revealed bilateral reductions in occipitotemporal and left superior frontal, and increases in inferior parietal, precuneus, and dorsolateral prefrontal activity. BOLD suppression in left posterior temporal, left inferior prefrontal, and right occipitotemporal cortex correlated with MEG repetition-related reductions. IEEG responses from all three regions supported the timecourse of MEG and localization of fMRI. Furthermore, iEEG decreases to repeated words were associated with decreased gamma power in several regions, providing evidence that gamma oscillations are tightly coupled to cognitive phenomena and reflect regional activations seen in the BOLD signal. PMID:20620212

  15. Benefits of Repetitive Transcranial Magnetic Stimulation (rTMS) for Spastic Subjects: Clinical, Functional, and Biomechanical Parameters for Lower Limb and Walking in Five Hemiparetic Patients

    PubMed Central

    Gross, Raphael; Leboeuf, Fabien; Desal, Hubert; Hamel, Olivier; Nguyen, Jean Paul; Pérot, Chantal; Buffenoir, Kévin

    2014-01-01

    Introduction. Spasticity is a disabling symptom resulting from reorganization of spinal reflexes no longer inhibited by supraspinal control. Several studies have demonstrated interest in repetitive transcranial magnetic stimulation in spastic patients. We conducted a prospective, randomized, double-blind crossover study on five spastic hemiparetic patients to determine whether this type of stimulation of the premotor cortex can provide a clinical benefit. Material and Methods. Two stimulation frequencies (1 Hz and 10 Hz) were tested versus placebo. Patients were assessed clinically, by quantitative analysis of walking and measurement of neuromechanical parameters (H and T reflexes, musculoarticular stiffness of the ankle). Results. No change was observed after placebo and 10 Hz protocols. Clinical parameters were not significantly modified after 1 Hz stimulation, apart from a tendency towards improved recruitment of antagonist muscles on the Fügl-Meyer scale. Only cadence and recurvatum were significantly modified on quantitative analysis of walking. Neuromechanical parameters were modified with significant decreases in Hmax⁡ /Mmax⁡ and T/Mmax⁡ ratios and stiffness indices 9 days or 31 days after initiation of TMS. Conclusion. This preliminary study supports the efficacy of low-frequency TMS to reduce reflex excitability and stiffness of ankle plantar flexors, while clinical signs of spasticity were not significantly modified. PMID:24883390

  16. [Functional imaging of deep brain stimulation in idiopathic Parkinson's disease].

    PubMed

    Hilker, R

    2010-10-01

    Functional brain imaging allows the effects of deep brain stimulation (DBS) on the living human brain to be investigated. In patients with advanced Parkinson's disease (PD), positron emission tomography (PET) studies were undertaken at rest as well as under motor, cognitive or behavioral activation. DBS leads to a reduction of abnormal PD-related network activity in the motor system, which partly correlates with the improvement of motor symptoms. The local increase of energy consumption within the direct target area suggests a predominant excitatory influence of the stimulation current on neuronal tissue. Remote effects of DBS of the subthalamic nucleus (STN) on frontal association cortices indicate an interference of stimulation energy with associative and limbic basal ganglia loops. Taken together, functional brain imaging provides very valuable data for advancement of the DBS technique in PD therapy.

  17. Toward proton MR spectroscopic imaging of stimulated brain function

    SciTech Connect

    Singh, M. . Dept. of Radiology)

    1992-08-01

    With the objective of complementing local cerebral metabolic studies of PET, and as a prelude to spectroscopic imaging, the authors have performed the first localized proton spectroscopic study of the stimulated human auditory cortex. Water suppressed localized spectroscopy (voxel size 3cm [times] 3cm [times] 3cm enclosing the auditory cortex, Te = 272ms, Tr = 3s) was performed on a 1.5T MRI/MRS system and spectra were acquired during stimulation with a 1kHz tone presented at 2Hz. Measurements were conducted for 30-40 min with a temporal resolution of 3.2 min (64 averages per time block). Results included in this paper from six subjects show a lactate peak which increases during stimulation compared to baseline values. These results suggest an increase in anaerobic glycolysis during stimulation and provide unique and valuable information that should complement glucose metabolism and flood flow studies of PET.

  18. Artistic creation as stimulated by superimposed versus separated visual images.

    PubMed

    Sobel, R S; Rothenberg, A

    1980-11-01

    An experiment was performed to examine the role of homospatial thinking in visual art. Each of 43 university-level art students produced three drawing stimulated by pairs of slides. Subjects were randomly assigned to view the pairs either superimposed on one another or separated on the screen. Drawings were independently judged by two internationally noted artists. As predicted, drawings containing an element from each component image intermingled were higher in creative potential when stimulated by the superimposed presentation; however, when sketches from either condition did not clearly contain images from both slides, the separated image presentation yielded the more creative result. Although results favor the hypothesis in part, the overall ambiguity of the data illustrates some of the difficulties in studying creative thought processes under experimental conditions.

  19. Intensity-dependent effects of repetitive anodal transcranial direct current stimulation on learning and memory in a rat model of Alzheimer's disease.

    PubMed

    Yu, Xuehong; Li, Yiyan; Wen, Huizhong; Zhang, Yinghui; Tian, Xuelong

    2015-09-01

    Single-session anodal transcranial direct current stimulation (tDCS) can improve the learning-memory function of patients with Alzheimer's disease (AD). After-effects of tDCS can be more significant if the stimulation is repeated regularly in a period. Here the behavioral and the histologic effects of the repetitive anodal tDCS on a rat model of AD were investigated. Sprague-Dawley rats were divided into 6 groups, the sham group, the β-amyloid (Aβ) group, the Aβ+20μA tDCS group, the Aβ+60μA tDCS group, the Aβ+100μA tDCS group and the Aβ+200μA tDCS group. Bilateral hippocampus of the rats in the Aβ group and the Aβ+tDCS groups were lesioned by Aβ1-40 to produce AD models. One day after drug injection, repetitive anodal tDCS (10 sessions in two weeks, 20min per session) was applied to the frontal cortex of the rats in the tDCS groups, while sham stimulation was applied to the Aβ group and the sham group. The spatial learning and memory capability of the rats were tested by Morris water maze. Bielschowsky's silver staining, Nissl's staining, choline acetyltransferase (ChAT) and glial-fibrillary-acidic protein (GFAP) immunohistochemistry of the hippocampus were conducted for histologic analysis. Results show in the Morris water maze task, rats in the Aβ+100μA and the Aβ+200μA tDCS groups had shorter escape latency and larger number of crossings on the platform. Significant histologic differences were observed in the Aβ+100μA and the Aβ+200μA tDCS groups compared to the Aβ group. The behavioral and the histological experiments indicate that the proposed repetitive anodal tDCS treatment can protect spatial learning and memory dysfunction of Aβ1-40-lesioned AD rats.

  20. Recovery of motor disability and spasticity in post-stroke after repetitive transcranial magnetic stimulation (rTMS).

    PubMed

    Málly, J; Dinya, E

    2008-07-01

    Lately it has been indicated that the stimulation of both sides of the motor cortices with different frequencies of rTMS can improve the behaviour of a paretic arm. We studied the effect of rTMS in severe cases of post-stroke after nearly 10 years. They had wide hemispheric lesion and their paresis had not changed for more than 5 years. The majority of patients could not move their fingers on the affected side. In our study we examined whether the active movement could be induced by rTMS even several years after stroke and which hemisphere (affected or unaffected) stimulated by rTMS would be the best location for attenuating the spasticity and for developing movement in the paretic arm. Sixty-four patients (more than 5 years after stroke in a stable state) were followed for 3 months. They were treated with rTMS with 1 Hz at 30% of 2.3T 100 stimuli per session twice a day for a week. The area to be stimulated was chosen according to the evoked movement by TMS in the paretic arm. That way, four groups were created and compared. In group A, where both hemispheres were stimulated (because of the single stimulation of TMS could induce movement from both sides of hemispheres) the spasticity decreased but the movement could not be influenced. A highly significant improvement in spasticity, in movement induction and in the behaviour of paresis was observed in group B, where before treatment, there was no evoked movement in the paretic arm from stimulating either hemispheres of the brain. For treatment we stimulated the unaffected hemisphere from where the intact arm is moved (ipsilateral to the paretic side). In both groups C (contralateral hemisphere to the paretic arm) and D (ipsilaterally evoked movement in the paretic arm), the spasticity decreased during the first week, but the movement of the paretic arm improved only in group C. It seems that spasticity can be modified by the stimulation either the affected or the unaffected hemisphere, but the induction of movement

  1. Bilateral responses of prefrontal and motor cortices to repetitive transcranial magnetic stimulation as measured by functional near infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Tian, Fenghua; Kozel, Frank Andrew; Dhamne, Sameer; McClintock, Shawn M.; Croarkin, Paul; Mapes, Kimberly; Husain, Mustafa M.; Liu, Hanli

    2009-02-01

    Simultaneously acquiring cortical functional Near Infrared Spectroscopy (fNIRS) during repeated Transcranial Magnetic Stimulation (rTMS) offers the possibility of directly investigating the effects of rTMS on brain regions without quantifiable behavioral changes. In this study, the left motor cortex and subsequently the left prefrontal cortex were stimulated at 1 Hz while fNIRS data was simultaneously acquired. Changes in hemodynamic signals were measured on both ipsilateral and contralateral sides. In each cortex, a significantly larger decrease in the concentration of oxygenated hemoglobin and a smaller increase in the concentration of deoxygenated hemoglobin during the stimulation periods were observed in both the motor and prefrontal cortices. The ipsilateral and contralateral changes showed high temporal consistency. Same experiment was repeated for each subject 2 or 3 days later. The hemodynamic responses associated with the stimulation showed good reproducibility in two sessions. To our knowledge, this is the first report of simultaneous fNIRS measurement of ipsilateral and contralateral changes of either the motor or prefrontal cortex during rTMS stimulation.

  2. Application of a high-repetition-rate laser diagnostic system for single-cycle-resolved imaging in internal combustion engines.

    PubMed

    Hult, Johan; Richter, Mattias; Nygren, Jenny; Aldén, Marcus; Hultqvist, Anders; Christensen, Magnus; Johansson, Bengt

    2002-08-20

    High-repetition-rate laser-induced fluorescence measurements of fuel and OH concentrations in internal combustion engines are demonstrated. Series of as many as eight fluorescence images, with a temporal resolution ranging from 10 micros to 1 ms, are acquired within one engine cycle. A multiple-laser system in combination with a multiple-CCD camera is used for cycle-resolved imaging in spark-ignition, direct-injection stratified-charge, and homogeneous-charge compression-ignition engines. The recorded data reveal unique information on cycle-to-cycle variations in fuel transport and combustion. Moreover, the imaging system in combination with a scanning mirror is used to perform instantaneous three-dimensional fuel-concentration measurements.

  3. Repeated BOLD-fMRI Imaging of Deep Brain Stimulation Responses in Rats

    PubMed Central

    Chao, Tzu-Hao Harry; Chen, Jyh-Horng; Yen, Chen-Tung

    2014-01-01

    Functional magnetic resonance imaging (fMRI) provides a picture of the global spatial activation pattern of the brain. Interest is growing regarding the application of fMRI to rodent models to investigate adult brain plasticity. To date, most rodent studies used an electrical forepaw stimulation model to acquire fMRI data, with α-chloralose as the anesthetic. However, α-chloralose is harmful to animals, and not suitable for longitudinal studies. Moreover, peripheral stimulation models enable only a limited number of brain regions to be studied. Processing between peripheral regions and the brain is multisynaptic, and renders interpretation difficult and uncertain. In the present study, we combined the medetomidine-based fMRI protocol (a noninvasive rodent fMRI protocol) with chronic implantation of an MRI-compatible stimulation electrode in the ventroposterior (VP) thalamus to repetitively sample thalamocortical responses in the rat brain. Using this model, we scanned the forebrain responses evoked by the VP stimulation repeatedly of individual rats over 1 week. Cortical BOLD responses were compared between the 2 profiles obtained at day1 and day8. We discovered reproducible frequency- and amplitude-dependent BOLD responses in the ipsilateral somatosensory cortex (S1). The S1 BOLD responses during the 2 sessions were conserved in maximal response amplitude, area size (size ratio from 0.88 to 0.91), and location (overlap ratio from 0.61 to 0.67). The present study provides a long-term chronic brain stimulation protocol for studying the plasticity of specific neural circuits in the rodent brain by BOLD-fMRI. PMID:24825464

  4. Repetitive Arg-Gly-Asp peptide as a cell-stimulating agent on electrospun poly(ϵ-caprolactone) scaffold for tissue engineering.

    PubMed

    Chaisri, Pacharaporn; Chingsungnoen, Artit; Siri, Sineenat

    2013-11-01

    Electrospun scaffolds derived from poly(ϵ-caprolactone) (PCL), a well known biodegradable material, have an architecture that is suitable for hosting cells. However, their biomedical applications are restricted because these scaffolds lack the bioactivity necessary to stimulate cell responses. In this work, a repetitive Arg-Gly-Asp (rRGD) peptide was produced as a cell-stimulating agent to provide the PCL scaffold with bioactivity. DNA encoding rRGD was amplified by polymerase chain reaction using overlap primers without a DNA template, and cloned into a protein expression vector to produce a His-tag fusion peptide. In an in vitro cell adhesion assay, the purified rRGD peptide, comprising 30 RGD repeats, promoted a 1.5-fold greater cell adhesion than the commercial tripeptide RGD. The rRGD peptide was immobilized onto an electrospun PCL scaffold that had been pretreated with argon plasma and graft-polymerized with acrylic acid. Fourier transform infrared (FTIR) analysis indicated that covalently linked rRGD peptide was present on the scaffold. The PCL scaffold with immobilized rRGD showed significantly changed hydrophilic properties and an enhanced adhesion and proliferation of mouse fibroblast cells by 2.3- and 2.9-fold, respectively, compared to the PCL scaffold alone. Through its ability to promote cell adhesion and proliferation, the rRGD peptide has great potential as a stimulant for improving the suboptimal cell-matrix interaction of polymeric scaffolds for tissue engineering applications.

  5. A pilot double-blind sham-controlled trial of repetitive transcranial magnetic stimulation for patients with refractory schizophrenia treated with clozapine.

    PubMed

    de Jesus, Danilo Rocha; Gil, Alexei; Barbosa, Leonardo; Lobato, Maria Inês; Magalhães, Pedro Vieira da Silva; Favalli, Gabriela Pereira de Souza; Marcolin, Marco Antonio; Daskalakis, Zafiris Jeffrey; Belmonte-de-Abreu, Paulo da Silva

    2011-07-30

    Schizophrenia is a complex and heterogeneous psychiatric disorder. Auditory verbal hallucinations occur in 50-70% of patients with schizophrenia and are associated with significant distress, decreased quality of life and impaired social functioning. This study aimed to investigate the effects of active compared with sham 1-Hz repetitive transcranial magnetic stimulation (rTMS) applied to the left temporal-parietal cortex in patients with schizophrenia treated with clozapine. Symptom dimensions that were evaluated included general psychopathology, severity of auditory hallucinations, quality of life and functionality. Seventeen right-handed patients with refractory schizophrenia experiencing auditory verbal hallucinations and treated with clozapine were randomly allocated to receive either active rTMS or sham stimulation. A total of 384 min of rTMS was administered over 20 days using a double-masked, sham-controlled, parallel design. There was a significant reduction in Brief Psychiatric Rating Scale (BPRS) scores in the active group compared with the sham group. There was no significant difference between active and sham rTMS on Quality of Life Scale (QLS), Auditory Hallucinations Rating Scale (AHRS), Clinical Global Impressions (CGI) and functional assessment staging (FAST) scores. Compared with sham stimulation, active rTMS of the left temporoparietal cortex in clozapine-treated patients showed a positive effect on general psychopathology. However, there was no effect on refractory auditory hallucinations. Further studies with larger sample sizes are needed to confirm these findings.

  6. The efficacy of cerebellar vermal deep high frequency (theta range) repetitive transcranial magnetic stimulation (rTMS) in schizophrenia: A randomized rater blind-sham controlled study.

    PubMed

    Garg, Shobit; Sinha, Vinod Kumar; Tikka, Sai Krishna; Mishra, Preeti; Goyal, Nishant

    2016-09-30

    Repetitive transcranial magnetic stimulation (rTMS) is a promising therapeutic for schizophrenia. Treatment effects of rTMS have been variable across different symptom clusters, with negative symptoms showing better response, followed by auditory hallucinations. Cerebellum, especially vermis and its abnormalities (both structural and functional) have been implicated in cognitive, affective and positive symptoms of schizophrenia. rTMS to this alternate site has been suggested as a novel target for treating patients with this disorder. Hypothesizing cerebellar vermal magnetic stimulation as an adjunct to treat schizophrenia psychopathology, we conducted a double blind randomized sham controlled rTMS study. In this study, forty patients were randomly allocated (using block randomization method) to active high frequency (theta patterned) rTMS (n=20) and sham (n=20) groups. They received 10 sessions over 2 weeks. The Positive and Negative Syndrome Scale (PANSS) and Calgary Depression Scale for Schizophrenia (CDSS) scores were assessed at baseline, after last session and at 4 weeks (2 weeks post-rTMS). We found a significantly greater improvement in the group receiving active rTMS sessions, compared to the sham group on negative symptoms, and depressive symptoms. We conclude that cerebellar stimulation can be used as an effective adjunct to treat negative and affective symptoms.

  7. Extracellular stimulation of mammalian neurons through repetitive activation of Na+ channels by weak capacitive currents on a silicon chip.

    PubMed

    Schoen, Ingmar; Fromherz, Peter

    2008-07-01

    Reliable extracellular stimulation of neuronal activity is the prerequisite for electrical interfacing of cultured networks and brain slices, as well as for neural implants. Safe stimulation must be achieved without damage to the cells. With respect to a future application of highly integrated semiconductor chips, we present an electrophysiological study of capacitive stimulation of mammalian cells in the geometry of adhesion on an insulated titanium dioxide/silicon electrode. We used HEK293 cells with overexpressed Na(V)1.4 channels and neurons from rat hippocampus. Weak biphasic stimuli of falling and rising voltage ramps were applied in the absence of Faradaic current and electroporation. We recorded the response of the intra- and extracellular voltage and evaluated the concomitant polarization of the attached and free cell membranes. Falling ramps efficiently depolarized the central area of the attached membrane. A transient sodium inward current was activated that gave rise to a weak depolarization of the cell on the order of 1 mV. The depolarization could be enhanced step by step by a train of biphasic stimuli until self-excitation of sodium channels set in. We applied the same protocol to cultured rat neurons and found that pulse trains of weak capacitive stimuli were able to elicit action potentials. Our results provide a basis for safe extracellular stimulation not only for cultured neurons on insulated semiconductor electrodes, but also more generally for metal electrodes in cell culture and brain tissue.

  8. Significant CMAP decrement by repetitive nerve stimulation is more frequent in median than ulnar nerves of patients with amyotrophic lateral sclerosis.

    PubMed

    Yamashita, Satoshi; Sakaguchi, Hideya; Mori, Akira; Kimura, En; Maeda, Yasushi; Hirano, Teruyuki; Uchino, Makoto

    2012-03-01

    Several studies have shown a significant amplitude decrement in compound muscle action potentials (CMAPs) on repetitive nerve stimulation (RNS) of muscles involved in amyotrophic lateral sclerosis (ALS). In ALS, muscle wasting preferentially affects the thenar muscles (APB) rather than the hypothenar muscles (ADM). We performed RNS studies in the APB and ADM muscles of 32 ALS patients to determine whether the effect of RNS differs between the median and ulnar nerves. The decremental responses to RNS were greater in the APB than in the ADM. Reduced CMAP amplitude was negatively correlated with CMAP decrement in median but not in ulnar nerves. The greater CMAP decrement in median nerve is attributable to preferential involvement of the APB in the pathophysiology of ALS or some underlying difference in the biology of the two muscles/nerves. Further investigations will better our understanding of the pathophysiology of ALS. Copyright © 2011 Wiley Periodicals, Inc.

  9. Repetitive transcranial magnetic stimulation causes a short-term increase in the duration of the cortical silent period in patients with Parkinson's disease.

    PubMed

    Siebner, H R; Mentschel, C; Auer, C; Lehner, C; Conrad, B

    2000-04-28

    In ten patients with Parkinson's disease (PD) and ten age-matched healthy controls, we applied 15 30-s trains of subthreshold 5-Hz repetitive transcranial magnetic stimulation (rTMS) over the primary motor hand area. Ten minutes after rTMS, PD patients showed a significant prolongation of the transcranially evoked silent period (SP) in the contralateral first dorsal interosseus muscle, whereas the SP remained unchanged in healthy subjects. Since the duration of the transcranially evoked SP is a well-established measure of intracortical inhibition, this finding demonstrates that rTMS is capable of inducing a short-term increase in intracortical inhibition in PD. The lack of a prolongation of the SP in healthy controls suggests that PD patients may be particularly susceptible to modulatory effects of rTMS on motocortical inhibition.

  10. Cognitive component of psychomotor retardation in unipolar and bipolar depression: Is verbal fluency a relevant marker? Impact of repetitive transcranial stimulation.

    PubMed

    Thomas-Ollivier, Véronique; Foyer, Emmanuelle; Bulteau, Samuel; Pichot, Anne; Valriviere, Pierre; Sauvaget, Anne; Deschamps, Thibault

    2017-09-01

    In the literature, psychomotor retardation (PMR) is increasingly highlighted as a relevant marker for depression. Currently, we chose to focus on the fluency capacities as an evaluation of the frontal lobes functioning to reach a better understanding of cognitive and neurobiological mechanisms involved in PMR in depression. The aims of this study were: (i) to explore the cognitive component of PMR through the analysis of verbal fluency (VF) performance in unipolar and bipolar depression; and (ii) to examine whether a repetitive transcranial magnetic stimulation treatment could improve concomitantly the PMR and VF capacities, as a relevant marker characteristic of the cognitive component of PMR. Fifteen unipolar and 15 bipolar patients were compared to 15 healthy adults. Before treatment, the results showed VF deficits, particularly marked in the bipolar group. The investigation of the interplay between PMR, VF performance, Montgomery-Åsberg Depression Rating Scale scores, and Montreal Cognitive Assessment scores showed that the deficits in these various dimensions were not homogeneous. The absence of correlation between the psychomotor retardation scale (the French Retardation Rating Scale for Depression) and VF, and the correlation with MoCA raise the hypothesis of a more global cognitive impairment associated with PMR in the BD group. The repetitive transcranial magnetic stimulation treatment had a positive impact on depression, PMR, and fluency scores. Correlations between the Retardation Rating Scale for Depression and VF performances appeared after treatment, showing the cognitive role of psychomotor functioning in depression. Further analyses, including other cognitive measures in an objective evaluation of PMR, are required for a better understanding of these complex relationships. © 2017 The Authors. Psychiatry and Clinical Neurosciences © 2017 Japanese Society of Psychiatry and Neurology.

  11. Hyperspectral imaging with stimulated Raman scattering by chirped femtosecond lasers.

    PubMed

    Fu, Dan; Holtom, Gary; Freudiger, Christian; Zhang, Xu; Xie, Xiaoliang Sunney

    2013-04-25

    Raman microscopy is a quantitative, label-free, and noninvasive optical imaging technique for studying inhomogeneous systems. However, the feebleness of Raman scattering significantly limits the use of Raman microscopy to low time resolutions and primarily static samples. Recent developments in narrowband stimulated Raman scattering (SRS) microscopy have significantly increased the acquisition speed of Raman based label-free imaging by a few orders of magnitude, at the expense of reduced spectroscopic information. On the basis of a spectral focusing approach, we present a fast SRS hyperspectral imaging system using chirped femtosecond lasers to achieve rapid Raman spectra acquisition while retaining the full speed and image quality of narrowband SRS imaging. We demonstrate that quantitative concentration determination of cholesterol in the presence of interfering chemical species can be achieved with sensitivity down to 4 mM. For imaging purposes, hyperspectral imaging data in the C-H stretching region is obtained within a minute. We show that mammalian cell SRS hyperspectral imaging reveals the spatially inhomogeneous distribution of saturated lipids, unsaturated lipids, cholesterol, and protein. The combination of fast spectroscopy and label-free chemical imaging will enable new applications in studying biological systems and material systems.

  12. Repetitive Transcranial Direct Current Stimulation Induced Excitability Changes of Primary Visual Cortex and Visual Learning Effects—A Pilot Study

    PubMed Central

    Sczesny-Kaiser, Matthias; Beckhaus, Katharina; Dinse, Hubert R.; Schwenkreis, Peter; Tegenthoff, Martin; Höffken, Oliver

    2016-01-01

    Studies on noninvasive motor cortex stimulation and motor learning demonstrated cortical excitability as a marker for a learning effect. Transcranial direct current stimulation (tDCS) is a non-invasive tool to modulate cortical excitability. It is as yet unknown how tDCS-induced excitability changes and perceptual learning in visual cortex correlate. Our study aimed to examine the influence of tDCS on visual perceptual learning in healthy humans. Additionally, we measured excitability in primary visual cortex (V1). We hypothesized that anodal tDCS would improve and cathodal tDCS would have minor or no effects on visual learning. Anodal, cathodal or sham tDCS were applied over V1 in a randomized, double-blinded design over four consecutive days (n = 30). During 20 min of tDCS, subjects had to learn a visual orientation-discrimination task (ODT). Excitability parameters were measured by analyzing paired-stimulation behavior of visual-evoked potentials (ps-VEP) and by measuring phosphene thresholds (PTs) before and after the stimulation period of 4 days. Compared with sham-tDCS, anodal tDCS led to an improvement of visual discrimination learning (p < 0.003). We found reduced PTs and increased ps-VEP ratios indicating increased cortical excitability after anodal tDCS (PT: p = 0.002, ps-VEP: p = 0.003). Correlation analysis within the anodal tDCS group revealed no significant correlation between PTs and learning effect. For cathodal tDCS, no significant effects on learning or on excitability could be seen. Our results showed that anodal tDCS over V1 resulted in improved visual perceptual learning and increased cortical excitability. tDCS is a promising tool to alter V1 excitability and, hence, perceptual visual learning. PMID:27375452

  13. Repetitive Transcranial Direct Current Stimulation Induced Excitability Changes of Primary Visual Cortex and Visual Learning Effects-A Pilot Study.

    PubMed

    Sczesny-Kaiser, Matthias; Beckhaus, Katharina; Dinse, Hubert R; Schwenkreis, Peter; Tegenthoff, Martin; Höffken, Oliver

    2016-01-01

    Studies on noninvasive motor cortex stimulation and motor learning demonstrated cortical excitability as a marker for a learning effect. Transcranial direct current stimulation (tDCS) is a non-invasive tool to modulate cortical excitability. It is as yet unknown how tDCS-induced excitability changes and perceptual learning in visual cortex correlate. Our study aimed to examine the influence of tDCS on visual perceptual learning in healthy humans. Additionally, we measured excitability in primary visual cortex (V1). We hypothesized that anodal tDCS would improve and cathodal tDCS would have minor or no effects on visual learning. Anodal, cathodal or sham tDCS were applied over V1 in a randomized, double-blinded design over four consecutive days (n = 30). During 20 min of tDCS, subjects had to learn a visual orientation-discrimination task (ODT). Excitability parameters were measured by analyzing paired-stimulation behavior of visual-evoked potentials (ps-VEP) and by measuring phosphene thresholds (PTs) before and after the stimulation period of 4 days. Compared with sham-tDCS, anodal tDCS led to an improvement of visual discrimination learning (p < 0.003). We found reduced PTs and increased ps-VEP ratios indicating increased cortical excitability after anodal tDCS (PT: p = 0.002, ps-VEP: p = 0.003). Correlation analysis within the anodal tDCS group revealed no significant correlation between PTs and learning effect. For cathodal tDCS, no significant effects on learning or on excitability could be seen. Our results showed that anodal tDCS over V1 resulted in improved visual perceptual learning and increased cortical excitability. tDCS is a promising tool to alter V1 excitability and, hence, perceptual visual learning.

  14. Task Type Affects Location of Language-Positive Cortical Regions by Repetitive Navigated Transcranial Magnetic Stimulation Mapping

    PubMed Central

    Hauck, Theresa; Tanigawa, Noriko; Probst, Monika; Wohlschlaeger, Afra; Ille, Sebastian; Sollmann, Nico; Maurer, Stefanie; Zimmer, Claus; Ringel, Florian; Meyer, Bernhard; Krieg, Sandro M.

    2015-01-01

    Objectives Recent repetitive TMS (rTMS) mapping protocols for language mapping revealed deficits of this method, mainly in posterior brain regions. Therefore this study analyzed the impact of different language tasks on the localization of language-positive brain regions and compared their effectiveness, especially with regard to posterior brain regions. Methods Nineteen healthy, right-handed subjects performed object naming, pseudoword reading, verb generation, and action naming during rTMS language mapping of the left hemisphere. Synchronically, 5 Hz/10 pulses were applied with a 0 ms delay Results The object naming task evoked the highest error rate (14%), followed by verb generation (13%) and action naming (11%). The latter revealed more errors in posterior than in anterior areas. Pseudoword reading barely generated errors, except for phonological paraphasias. Conclusions In general, among the evaluated language tasks, object naming is the most discriminative task to detect language-positive regions via rTMS. However, other tasks might be used for more specific questions. PMID:25928744

  15. Transcranial magnetic stimulation assisted by neuronavigation of magnetic resonance images

    NASA Astrophysics Data System (ADS)

    Viesca, N. Angeline; Alcauter, S. Sarael; Barrios, A. Fernando; González, O. Jorge J.; Márquez, F. Jorge A.

    2012-10-01

    Technological advance has improved the way scientists and doctors can learn about the brain and treat different disorders. A non-invasive method used for this is Transcranial Magnetic Stimulation (TMS) based on neuron excitation by electromagnetic induction. Combining this method with functional Magnetic Resonance Images (fMRI), it is intended to improve the localization technique of cortical brain structures by designing an extracranial localization system, based on Alcauter et al. work.

  16. Low Frequency Repetitive Transcranial Magnetic Stimulation to Improve Motor Function and Grip Force of Upper Limbs of Patients With Hemiplegia

    PubMed Central

    Motamed Vaziri, Poopak; Bahrpeyma, Farid; Firoozabadi, Mohammad; Forough, Bijan; Hatef, Boshra; Sheikhhoseini, Rahman; Shamili, Aryan

    2014-01-01

    Background: Stroke is the most common and debilitating neurological disorder among adults, and is a sudden onset of neurological signs caused by brain blood vessels impairments. Objectives: Some new therapeutic methods focus on the use of magnetic stimulation to produce therapeutic effects by inducing the currents. The aim of this study is to determine the effects of rTMS plus routine rehabilitation on hand grip and wrist motor functions in patients with hemiplegia, and compare with pure routine rehabilitation programs. Patients and Methods: In this study, 12 patients with hemiplegia were randomly divided in two groups. Control group, received the rehabilitation program with placebo magnetic stimulation, and the experimental group, received magnetic stimulation with routine rehabilitation program for 10 sessions for three times per week. Pre and post evaluations of treatment performed using Barthel and Fugl-Meyer indices and dynamometers. Results: In the control group, Barthel and Fugl-Meyer indices showed significant improvement (P = 0.01, P = 0.00), while in the experimental group, significant improvement in Barthel and Fugl-Meyer indices and dynamometers has been observed (P = 0.01, P = 0.00, P = 0.007). Conclusions: rTMS can improve hand muscle force and functions of patients with chronic hemiplegia, while conventional treatment is not effective. PMID:25389476

  17. Effects of repetitive peripheral magnetic stimulation on upper-limb spasticity and impairment in patients with spastic hemiparesis: a randomized, double-blind, sham-controlled study.

    PubMed

    Krewer, Carmen; Hartl, Sandra; Müller, Friedemann; Koenig, Eberhard

    2014-06-01

    To investigate short-term and long-term effects of repetitive peripheral magnetic stimulation (rpMS) on spasticity and motor function. Monocentric, randomized, double-blind, sham-controlled trial. Neurologic rehabilitation hospital. Patients (N=66) with severe hemiparesis and mild to moderate spasticity resulting from a stroke or a traumatic brain injury. The average time ± SD since injury for the intervention groups was 26 ± 71 weeks or 37 ± 82 weeks. rpMS for 20 minutes or sham stimulation with subsequent occupational therapy for 20 minutes, 2 times a day, over a 2-week period. Modified Tardieu Scale and Fugl-Meyer Assessment (arm score), assessed before therapy, at the end of the 2-week treatment period, and 2 weeks after study treatment. Additionally, the Tardieu Scale was assessed after the first and before the third therapy session to determine any short-term effects. Spasticity (Tardieu >0) was present in 83% of wrist flexors, 62% of elbow flexors, 44% of elbow extensors, and 10% of wrist extensors. Compared with the sham stimulation group, the rpMS group showed short-term effects on spasticity for wrist flexors (P=.048), and long-term effects for elbow extensors (P<.045). Arm motor function (rpMS group: median 5 [4-27]; sham group: median 4 [4-9]) did not significantly change over the study period in either group, whereas rpMS had a positive effect on sensory function. Therapy with rpMS increases sensory function in patients with severe limb paresis. The magnetic stimulation, however, has limited effect on spasticity and no effect on motor function. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  18. Comparison of the effects of high- and low-frequency repetitive transcranial magnetic stimulation on upper limb hemiparesis in the early phase of stroke.

    PubMed

    Sasaki, Nobuyuki; Mizutani, Saneyuki; Kakuda, Wataru; Abo, Masahiro

    2013-05-01

    Recently, high-frequency repetitive transcranial magnetic stimulation (HF-rTMS) and low-frequency rTMS (LF-rTMS) are reported to improve motor function significantly in chronic hemiparetic stroke patients. However, few studies have investigated the safety and efficacy of these rTMS modalities introduced during the early phase of stroke. The purpose of this study was to clarify the rTMS modality that is more beneficial for upper limb hemiparesis in the early phase of stroke using a randomized controlled trial. Twenty-nine patients with a hemispheric stroke lesion in the early phase of stroke were examined. Patients were randomly assigned into 3 groups: the HF-rTMS group (10 Hz rTMS to the lesional hemisphere [n = 9]), the LF-rTMS group (1 Hz rTMS to the nonlesional hemisphere [n = 11]), and the sham stimulation group [n = 9]). Patients received sessions for 5 consecutive days. Grip strength and tapping frequency were assessed before and after the intervention. Motor improvement of the affected upper limb after intervention was compared among the 3 groups. All patients completed the 5-day protocol. Both the HF-rTMS and LF-rTMS groups had significant increases in both grip strength and tapping frequency. Comparison of the extent of improvement showed a more significant increase in grip strength and tapping frequency in the HF-rTMS group compared to the sham stimulation group (each P < .05), and no difference between the LF-rTMS group and the sham stimulation group. HF-rTMS applied to the lesional hemisphere in the early phase of stroke was more beneficial for motor improvement of the affected upper limb than LF-rTMS. Copyright © 2013 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  19. Effect of single-session repetitive transcranial magnetic stimulation applied over the hand versus leg motor area on pain after spinal cord injury.

    PubMed

    Jetté, Fanny; Côté, Isabelle; Meziane, Hadj Boumediene; Mercier, Catherine

    2013-09-01

    Neuropathic pain often follows spinal cord injury (SCI). To compare the effect of repetitive transcranial magnetic stimulation (rTMS) applied over different motor cortex targets (hand vs leg area) versus sham stimulation on neuropathic pain and local neurophysiological changes in patients with SCI. A total of 16 patients with complete or incomplete motor SCI and chronic neuropathic pain participated in a double-blind, cross-over randomized study. Three single sessions of sham or active rTMS (10 Hz, total of 2000 stimuli) were applied in random order over the hand or leg area with a minimal 2-week interval. THE MAIN OUTCOME MEASURES: were the numeric rating scale for pain sensation and parameters derived from motor mapping of the first dorsal interosseous muscle, including maximal amplitude of evoked response as well as map area, volume, and location. rTMS applied to either the hand or the leg area, but not sham stimulation, induced a significant but equivalent reduction in pain for the first 48 hours postintervention (P < .05). Participants with an incomplete lesion showed greater analgesia than those with a complete lesion (21% vs. 3%, respectively; P < .05). The main change observed for motor map measurements was an increase in corticospinal excitability after stimulation of the hand area (P = .04) but not for the other conditions. rTMS applied over the hand or leg motor cortex decreased neuropathic pain regardless of any change in cortical excitability, suggesting that the analgesic effect is not associated with local changes at the motor cortex level itself.

  20. Smoking cessation induced by deep repetitive transcranial magnetic stimulation of the prefrontal and insular cortices: a prospective, randomized controlled trial.

    PubMed

    Dinur-Klein, Limor; Dannon, Pinhas; Hadar, Aviad; Rosenberg, Oded; Roth, Yiftach; Kotler, Moshe; Zangen, Abraham

    2014-11-01

    Tobacco smoking is the leading cause of preventable death in developed countries. Our previous studies in animal models and humans suggest that repeated activation of cue-induced craving networks followed by electromagnetic stimulation of the dorsal prefrontal cortex (PFC) can cause lasting reductions in drug craving and consumption. We hypothesized that disruption of these circuitries by deep transcranial magnetic stimulation (TMS) of the PFC and insula bilaterally can induce smoking cessation. Adults (N = 115) who smoke at least 20 cigarettes/day and failed previous treatments were recruited from the general population. Participants were randomized to receive 13 daily sessions of high-frequency, low-frequency or sham stimulation following, or without, presentation of smoking cues. Deep TMS was administered using an H-coil version targeting the lateral PFC and insula bilaterally. Cigarette consumption was evaluated during the treatment by measuring cotinine levels in urine samples and recording participants' self-reports as a primary outcome variable. Dependence and craving were assessed using standardized questionnaires. High (but not low) frequency deep TMS treatment significantly reduced cigarette consumption and nicotine dependence. The combination of this treatment with exposure to smoking cues enhanced reduction in cigarette consumption leading to an abstinence rate of 44% at the end of the treatment and an estimated 33% 6 months following the treatment. This study further implicates the lateral PFC and insula in nicotine addiction and suggests the use of deep high-frequency TMS of these regions following presentation of smoking cues as a promising treatment strategy. Copyright © 2014 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  1. A fronto-parietal network is mediating improvement of motor function related to repetitive peripheral magnetic stimulation: A PET-H2O15 study.

    PubMed

    Struppler, Albrecht; Binkofski, Ferdinand; Angerer, Bernhard; Bernhardt, Michael; Spiegel, Sabine; Drzezga, Alexander; Bartenstein, Peter

    2007-01-01

    Repetitive peripheral magnetic stimulation (RPMS) is a focused and painless stimulation method, in which muscle contractions are elicited by depolarization of the terminal motor branches. Clinical-experimental investigations on different disorders of sensorimotor integration in the last decade have shown that RPMS can be used for the rehabilitation of motor functions after stroke. It is supposed that this therapeutic effect is based on the RPMS-induced proprioceptive inflow to the CNS. To analyze the conditioning effects of RPMS on reorganization of the motor system on cortical level positron emission tomography (PET) is used. Regional cerebral blood flow (rCBF) has been measured using H(2)O(15)-PET in eight patients with arm paresis following focal cerebral ischemic infarction before and after treatment using RPMS on upper arm flexor muscles. Behavioral measures showed a significant improvement of kinematics of finger movements and a reduction of spasticity in the affected arm following RPMS treatment. The recovery was associated with significant increase of neural activation within the superior posterior parietal lobe and the premotor cortex (PM) areas. The increase of activation of the parieto-premotor network following RPMS treatment indicates a significant conditioning effect of RPMS on the cortical level. These results emphasize the positive therapeutic effect of RPMS and describe the physiological bases of its function on the central level.

  2. Effects of repetitive transcranial magnetic stimulation of the unaffected hemisphere leg motor area in patients with subacute stroke and substantial leg impairment: A pilot study.

    PubMed

    Lin, Yen-Nung; Hu, Chaur-Jong; Chi, Ju-yang; Lin, Li-Fong; Yen, Tze-Hsun; Lin, Yen-Kuang; Liou, Tsan-Hon

    2015-04-01

    To evaluate the effects of repetitive transcranial magnetic stimulation (rTMS) on mobility among patients with substantial leg impairment after subacute stroke. Double-blinded, stratified, randomized trial involving a sham control group. Patients who developed unilateral hemiplegia after first-ever subacute stroke and underwent inpatient stroke rehabilitation. The 15-day intervention programme used in the present study included the application of rTMS (1 Hz, 15 min) over the leg motor area of the unaffected hemisphere, followed by 45 min physical therapy. Overall, 32 participants were randomly assigned to receive either real rTMS or sham stimulation. Clinical assessments, including the Postural Assessment Scale for Stroke Patients (PASS), balance subscale of the Performance Oriented Mobility Assessment (POMA-b), Fugl-Meyer Assessment, Barthel Index (BI), and Timed Up and Go test, were performed immediately before and after the intervention. Both groups demonstrated significant improvements in all the test results over time. At the post-test assessment, the patients in the real rTMS group demonstrated greater improvements in the PASS, POMA, and BI scores than did the patients in the sham rTMS group. In addition, a significantly higher number of patients in the real rTMS group regained mobility at the post-test assessment compared with the corresponding number of patients in the sham rTMS group. Application of 1-Hz rTMS may improve mobility among patients with substantial leg impairment after subacute stroke.

  3. High-Frequency Repetitive Transcranial Magnetic Stimulation (rTMS) Improves Functional Recovery by Enhancing Neurogenesis and Activating BDNF/TrkB Signaling in Ischemic Rats.

    PubMed

    Luo, Jing; Zheng, Haiqing; Zhang, Liying; Zhang, Qingjie; Li, Lili; Pei, Zhong; Hu, Xiquan

    2017-02-20

    Repetitive transcranial magnetic stimulation (rTMS) has rapidly become an attractive therapeutic approach for stroke. However, the mechanisms underlying this remain elusive. This study aimed to investigate whether high-frequency rTMS improves functional recovery mediated by enhanced neurogenesis and activation of brain-derived neurotrophic factor (BDNF)/tropomyosin-related kinase B (TrkB) pathway and to compare the effect of conventional 20 Hz rTMS and intermittent theta burst stimulation (iTBS) on ischemic rats. Rats after rTMS were sacrificed seven and 14 days after middle cerebral artery occlusion (MCAO), following evaluation of neurological function. Neurogenesis was measured using specific markers: Ki67, Nestin, doublecortin (DCX), NeuN and glial fibrillary acidic protein (GFAP), and the expression levels of BDNF were visualized by Western blotting and RT-PCR analysis. Both high-frequency rTMS methods significantly improved neurological function and reduced infarct volume. Moreover, 20 Hz rTMS and iTBS significantly promoted neurogenesis, shown by an increase of Ki67/DCX, Ki67/Nestin, and Ki67/NeuN-positive cells in the peri-infarct striatum. These beneficial effects were accompanied by elevated protein levels of BDNF and phosphorylated-TrkB. In conclusion, high-frequency rTMS improves functional recovery possibly by enhancing neurogenesis and activating BDNF/TrkB signaling pathway and conventional 20 Hz rTMS is better than iTBS at enhancing neurogenesis in ischemic rats.

  4. Add-on Effects of Repetitive Transcranial Magnetic Stimulation on Subacute Aphasia Therapy: Enhanced Improvement of Functional Communication and Basic Linguistic Skills. A Randomized Controlled Study.

    PubMed

    Rubi-Fessen, Ilona; Hartmann, Alexander; Huber, Walter; Fimm, Bruno; Rommel, Thomas; Thiel, Alexander; Heiss, Wolf-Dieter

    2015-11-01

    To determine to what extent repetitive transcranial magnetic stimulation (rTMS) combined with speech and language therapy improves functional communication and basic linguistic skills of individuals with subacute aphasia. Randomized, blinded, and sham-controlled study. Neurologic rehabilitation hospital. Participants (N=30) with subacute aphasia after stroke. During a 2-week treatment period, half of the participants received 10 sessions of 20-minute inhibitory 1-Hz rTMS over the right inferior frontal gyrus (Brodmann area 45), and the other half received sham stimulation. Directly thereafter, all the participants underwent 45 minutes of speech and language therapy. Aachen Aphasia Test, Amsterdam-Nijmegen Everyday Language Test (ANELT), a naming screening, and subscales of the FIM, all assessed the day before and the day after treatment period. The participants who received real rTMS significantly improved with respect to all 10 measures of basic linguistic skills and functional communication, whereas sham-treated participants significantly improved in only 6 of 10 measures (paired t tests, P<.05). There was a significant difference in the gains made by the 2 groups on 5 of 10 measures including functional communication (ANELT) (repeated-measures analysis of variance, P≤.05). For the first time, this study has demonstrated that basic linguistic skills as well as functional communication are bolstered by combining rTMS and behavioral language therapy in patients with subacute aphasia. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  5. Meta-analysis of the effects of repetitive transcranial magnetic stimulation (rTMS) on negative and positive symptoms in schizophrenia

    PubMed Central

    Freitas, Catarina; Fregni, Felipe; Pascual-Leone, Alvaro

    2009-01-01

    Background A growing body of evidence suggests that repetitive transcranial magnetic stimulation (rTMS) can alleviate negative and positive symptoms of refractory schizophrenia. However, trials to date have been small and results are mixed. Methods We performed meta-analyses of all prospective studies of the therapeutic application of rTMS in refractory schizophrenia assessing the effects of high-frequency rTMS to the left dorsolateral prefrontal cortex (DLPFC) to treat negative symptoms, and low-frequency rTMS to the left temporo-parietal cortex (TPC) to treat auditory hallucinations (AH) and overall positive symptoms. Results When analyzing controlled (active arms) and uncontrolled studies together, the effect sizes showed significant and moderate effects of rTMS on negative and positive symptoms (based on PANSS-N or SANS, and PANSS-P or SAPS, respectively). However, the analysis for the sham-controlled studies revealed a small non-significant effect size for negative (0.27, p=0.417) and for positive symptoms (0.17, p=0.129). When specifically analyzing AH (based on AHRS, HCS or SAH), the effect size for the sham-controlled studies was large and significant (1.04; p=0.002). Conclusions These meta-analyses support the need for further controlled, larger trials to assess the clinical efficacy of rTMS on negative and positive symptoms of schizophrenia, while suggesting the need for exploration for alternative stimulation protocols. PMID:19138833

  6. Ipsilesional High Frequency Repetitive Transcranial Magnetic Stimulation Add-On Therapy Improved Diffusion Parameters of Stroke Patients with Motor Dysfunction: A Preliminary DTI Study

    PubMed Central

    Guo, Zhiwei; Jin, Yu; Peng, Haitao; Xing, Guoqiang; Liao, Xiang; Wang, Yunfeng; Chen, Huaping; He, Bin; McClure, Morgan A.

    2016-01-01

    Purpose. The aim of this study was to evaluate the effects of high frequency repetitive transcranial magnetic stimulation (HF-rTMS) on stroke patients with motor dysfunction and to investigate the underlying neural mechanism. Methods. Fifteen stroke patients were assigned to the rTMS treatment (RT) group and conventional treatment (CT) group. Patients in the RT received 10 Hz rTMS stimulation on the ipsilesional primary motor cortex for 10 days plus conventional treatment of CT, which consisted of acupuncture and antiplatelet aggregation medication. Difference in fractional anisotropy (FA) between pretreatment and posttreatment and between two groups was determined. Correlations between FA values and neurological assessments were also calculated. Results. Both groups significantly improved the neurological function after treatment. rTMS-treated patients showed better improvement in Fugl-Meyer Assessment (FMA) score and increased FA value in motor-related white matter and gray matter cortices compared with CT-treated patients and pretreatment status. Besides, the increased FA value in the ipsilesional posterior limb of the internal capsule in RT group was significantly correlated with the improved FMA score. Significance. HF-rTMS could be a supplement therapy to CT in improving motor recovery in patients with stroke. And this benefit effect may be achieved through modulating the ipsilesional corticospinal tracts and motor-related gray matter cortices. PMID:27840742

  7. In Vitro Assessment Reveals Parameters-Dependent Modulation on Excitability and Functional Connectivity of Cerebellar Slice by Repetitive Transcranial Magnetic Stimulation

    PubMed Central

    Tang, Rongyu; Zhang, Guanghao; Weng, Xiechuan; Han, Yao; Lang, Yiran; Zhao, Yuwei; Zhao, Xiaobo; Wang, Kun; Lin, Qiuxia; Wang, Changyong

    2016-01-01

    Repetitive transcranial magnetic stimulation (rTMS) is an increasingly common technique used to selectively modify neural excitability and plasticity. There is still controversy concerning the cortical response to rTMS of different frequencies. In this study, a novel in vitro paradigm utilizing the Multi-Electrodes Array (MEA) system and acute cerebellar slicing is described. In a controllable environment that comprises perfusion, incubation, recording and stimulation modules, the spontaneous single-unit spiking activity in response to rTMS of different frequencies and powers was directly measured and analyzed. Investigation using this in vitro paradigm revealed frequency-dependent modulation upon the excitability and functional connectivity of cerebellar slices. The 1-Hz rTMS sessions induced short-term inhibition or lagged inhibition, whereas 20-Hz sessions induced excitation. The level of modulation is influenced by the value of power. However the long-term response fluctuated without persistent direction. The choice of evaluation method may also interfere with the interpretation of modulation direction. Furthermore, both short-term and long-term functional connectivity was strengthened by 1-Hz rTMS and weakened by 20-Hz rTMS. PMID:27000527

  8. Effect of low-frequency repetitive transcranial magnetic stimulation on sleep pattern and quality of life in patients with focal epilepsy.

    PubMed

    Sánchez-Escandón, O; Arana-Lechuga, Y; Terán-Pérez, G; Ruiz-Chow, A; González-Robles, R; Shkurovich-Bialik, P; Collado-Corona, M A; Velázquez-Moctezuma, J

    2016-04-01

    In this study we analyzed the effects of transcranial magnetic stimulation (TMS) on sleep and on the self-perceived quality of life in epileptic patients. A total of 24 male patients diagnosed with focal epilepsy were included in the study. Pharmacological treatment with levetiracetam was standardized at 2 g daily. Before TMS onset, all-night polysomnographic recording (PSG) was performed, and the Quality of Life in Epilepsy Inventory (QOLIE-31) was administered. Thereafter, patients underwent low-frequency repetitive TMS (1000 pulses/1 Hz) daily for 10 days. After the end of the treatment, a second polysomnographic study was performed, and the QOLIE-31 questionnaire was administered again. TMS induced a significant increase in sleep efficiency and in total sleep time, along with a decrease in sleep latency and the number of awakenings. In addition, the number of interictal discharges during sleep decreased significantly. Concerning the QOLIE-31 scale values, the patients showed great improvement in the self-perceived quality of life. The present results indicate that TMS may mediate therapeutic effects in the treatment of patients with focal epilepsy, and that TMS treatment is accompanied by improvement of sleep patterns as well as improvement in self-perceived quality of life. However, a study that includes a control group undergoing sham stimulation is needed to confirm these findings. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Effect of the stimulus frequency and pulse number of repetitive transcranial magnetic stimulation on the inter-reversal time of perceptual reversal on the right superior parietal lobule

    NASA Astrophysics Data System (ADS)

    Nojima, Kazuhisa; Ge, Sheng; Katayama, Yoshinori; Ueno, Shoogo; Iramina, Keiji

    2010-05-01

    The aim of this study is to investigate the effect of the stimulus frequency and pulses number of repetitive transcranial magnetic stimulation (rTMS) on the inter-reversal time (IRT) of perceptual reversal on the right superior parietal lobule (SPL). The spinning wheel illusion was used as the ambiguous figures stimulation in this study. To investigate the rTMS effect over the right SPL during perceptual reversal, 0.25 Hz 60 pulse, 1 Hz 60 pulse, 0.5 Hz 120 pulse, 1 Hz 120 pulse, and 1 Hz 240 pulse biphasic rTMS at 90% of resting motor threshold was applied over the right SPL and the right posterior temporal lobe (PTL), respectively. As a control, a no TMS was also conducted. It was found that rTMS on 0.25 Hz 60 pulse and 1 Hz 60 pulse applied over the right SPL caused shorter IRT. In contrast, it was found that rTMS on 1 Hz 240-pulse applied over the right SPL caused longer IRT. On the other hand, there is no significant difference between IRTs when the rTMS on 0.5 Hz 120 pulse and 1 Hz 120 pulse were applied over the right SPL. Therefore, the applying of rTMS over the right SPL suggests that the IRT of perceptual reversal is effected by the rTMS conditions such as the stimulus frequency and the number of pulses.

  10. Effect of inter-train interval on the induction of repetition suppression of motor-evoked potentials using transcranial magnetic stimulation.

    PubMed

    Pitkänen, Minna; Kallioniemi, Elisa; Julkunen, Petro

    2017-01-01

    Repetition suppression (RS) is evident as a weakened response to repeated stimuli after the initial response. RS has been demonstrated in motor-evoked potentials (MEPs) induced with transcranial magnetic stimulation (TMS). Here, we investigated the effect of inter-train interval (ITI) on the induction of RS of MEPs with the attempt to optimize the investigative protocols. Trains of TMS pulses, targeted to the primary motor cortex by neuronavigation, were applied at a stimulation intensity of 120% of the resting motor threshold. The stimulus trains included either four or twenty pulses with an inter-stimulus interval (ISI) of 1 s. The ITI was here defined as the interval between the last pulse in a train and the first pulse in the next train; the ITIs used here were 1, 3, 4, 6, 7, 12, and 17 s. RS was observed with all ITIs except with the ITI of 1 s, in which the ITI was equal to ISI. RS was more pronounced with longer ITIs. Shorter ITIs may not allow sufficient time for a return to baseline. RS may reflect a startle-like response to the first pulse of a train followed by habituation. Longer ITIs may allow more recovery time and in turn demonstrate greater RS. Our results indicate that RS can be studied with confidence at relatively short ITIs of 6 s and above.

  11. High-Frequency Repetitive Transcranial Magnetic Stimulation (rTMS) Improves Functional Recovery by Enhancing Neurogenesis and Activating BDNF/TrkB Signaling in Ischemic Rats

    PubMed Central

    Luo, Jing; Zheng, Haiqing; Zhang, Liying; Zhang, Qingjie; Li, Lili; Pei, Zhong; Hu, Xiquan

    2017-01-01

    Repetitive transcranial magnetic stimulation (rTMS) has rapidly become an attractive therapeutic approach for stroke. However, the mechanisms underlying this remain elusive. This study aimed to investigate whether high-frequency rTMS improves functional recovery mediated by enhanced neurogenesis and activation of brain-derived neurotrophic factor (BDNF)/tropomyosin-related kinase B (TrkB) pathway and to compare the effect of conventional 20 Hz rTMS and intermittent theta burst stimulation (iTBS) on ischemic rats. Rats after rTMS were sacrificed seven and 14 days after middle cerebral artery occlusion (MCAO), following evaluation of neurological function. Neurogenesis was measured using specific markers: Ki67, Nestin, doublecortin (DCX), NeuN and glial fibrillary acidic protein (GFAP), and the expression levels of BDNF were visualized by Western blotting and RT-PCR analysis. Both high-frequency rTMS methods significantly improved neurological function and reduced infarct volume. Moreover, 20 Hz rTMS and iTBS significantly promoted neurogenesis, shown by an increase of Ki67/DCX, Ki67/Nestin, and Ki67/NeuN-positive cells in the peri-infarct striatum. These beneficial effects were accompanied by elevated protein levels of BDNF and phosphorylated-TrkB. In conclusion, high-frequency rTMS improves functional recovery possibly by enhancing neurogenesis and activating BDNF/TrkB signaling pathway and conventional 20 Hz rTMS is better than iTBS at enhancing neurogenesis in ischemic rats. PMID:28230741

  12. Infrared thermal imaging of rat somatosensory cortex with whisker stimulation.

    PubMed

    Suzuki, Takashi; Ooi, Yasuhiro; Seki, Junji

    2012-04-01

    The present study aims to validate the applicability of infrared (IR) thermal imaging for the study of brain function through experiments on the rat barrel cortex. Regional changes in neural activity within the brain produce alterations in local thermal equilibrium via increases in metabolic activity and blood flow. We studied the relationship between temperature change and neural activity in anesthetized rats using IR imaging to visualize stimulus-induced changes in the somatosensory cortex of the brain. Sensory stimulation of the vibrissae (whiskers) was given for 10 s using an oscillating whisker vibrator (5-mm deflection at 10, 5, and 1 Hz). The brain temperature in the observational region continued to increase significantly with whisker stimulation. The mean peak recorded temperature changes were 0.048 ± 0.028, 0.054 ± 0.036, and 0.097 ± 0.015°C at 10, 5, and 1 Hz, respectively. We also observed that the temperature increase occurred in a focal spot, radiating to encompass a larger region within the contralateral barrel cortex region during single-whisker stimulation. Whisker stimulation also produced ipsilateral cortex temperature increases, which were localized in the same region as the pial arterioles. Temperature increase in the barrel cortex was also observed in rats treated with a calcium channel blocker (nimodipine), which acts to suppress the hemodynamic response to neural activity. Thus the location and area of temperature increase were found to change in accordance with the region of neural activation. These results indicate that IR thermal imaging is viable as a functional quantitative neuroimaging technique.

  13. Monitoring Cortical Excitability during Repetitive Transcranial Magnetic Stimulation in Children with ADHD: A Single-Blind, Sham-Controlled TMS-EEG Study

    PubMed Central

    Helfrich, Christian; Pierau, Simone S.; Freitag, Christine M.; Roeper, Jochen; Ziemann, Ulf; Bender, Stephan

    2012-01-01

    Background Repetitive transcranial magnetic stimulation (rTMS) allows non-invasive stimulation of the human brain. However, no suitable marker has yet been established to monitor the immediate rTMS effects on cortical areas in children. Objective TMS-evoked EEG potentials (TEPs) could present a well-suited marker for real-time monitoring. Monitoring is particularly important in children where only few data about rTMS effects and safety are currently available. Methods In a single-blind sham-controlled study, twenty-five school-aged children with ADHD received subthreshold 1 Hz-rTMS to the primary motor cortex. The TMS-evoked N100 was measured by 64-channel-EEG pre, during and post rTMS, and compared to sham stimulation as an intraindividual control condition. Results TMS-evoked N100 amplitude decreased during 1 Hz-rTMS and, at the group level, reached a stable plateau after approximately 500 pulses. N100 amplitude to supra-threshold single pulses post rTMS confirmed the amplitude reduction in comparison to the pre-rTMS level while sham stimulation had no influence. EEG source analysis indicated that the TMS-evoked N100 change reflected rTMS effects in the stimulated motor cortex. Amplitude changes in TMS-evoked N100 and MEPs (pre versus post 1 Hz-rTMS) correlated significantly, but this correlation was also found for pre versus post sham stimulation. Conclusion The TMS-evoked N100 represents a promising candidate marker to monitor rTMS effects on cortical excitability in children with ADHD. TMS-evoked N100 can be employed to monitor real-time effects of TMS for subthreshold intensities. Though TMS-evoked N100 was a more sensitive parameter for rTMS-specific changes than MEPs in our sample, further studies are necessary to demonstrate whether clinical rTMS effects can be predicted from rTMS-induced changes in TMS-evoked N100 amplitude and to clarify the relationship between rTMS-induced changes in TMS-evoked N100 and MEP amplitudes. The TMS-evoked N100 amplitude

  14. Recovery from Object Substitution Masking Induced by Transient Suppression of Visual Motion Processing: A Repetitive Transcranial Magnetic Stimulation Study

    ERIC Educational Resources Information Center

    Hirose, Nobuyuki; Kihara, Ken; Mima, Tatsuya; Ueki, Yoshino; Fukuyama, Hidenao; Osaka, Naoyuki

    2007-01-01

    Object substitution masking is a form of visual backward masking in which a briefly presented target is rendered invisible by a lingering mask that is too sparse to produce lower image-level interference. Recent studies suggested the importance of an updating process in a higher object-level representation, which should rely on the processing of…

  15. Recovery from Object Substitution Masking Induced by Transient Suppression of Visual Motion Processing: A Repetitive Transcranial Magnetic Stimulation Study

    ERIC Educational Resources Information Center

    Hirose, Nobuyuki; Kihara, Ken; Mima, Tatsuya; Ueki, Yoshino; Fukuyama, Hidenao; Osaka, Naoyuki

    2007-01-01

    Object substitution masking is a form of visual backward masking in which a briefly presented target is rendered invisible by a lingering mask that is too sparse to produce lower image-level interference. Recent studies suggested the importance of an updating process in a higher object-level representation, which should rely on the processing of…

  16. Exploring infrared neural stimulation with multimodal nonlinear imaging (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Adams, Wilson R.; Mahadevan-Jansen, Anita

    2017-02-01

    Infrared neural stimulation (INS) provides optical control of neural excitability using near to mid-infrared (mid-IR) light, which allows for spatially selective, artifact-free excitation without the introduction of exogenous agents or genetic modification. Although neural excitability is mediated by a transient temperature increase due to water absorption of IR energy, the molecular nature of IR excitability in neural tissue remains unknown. Current research suggests that transient changes in local tissue temperature give rise to a myriad of cellular responses that have been individually attributed to IR mediated excitability. To further elucidate the underlying biophysical mechanisms, we have begun work towards employing a novel multimodal nonlinear imaging platform to probe the molecular underpinnings of INS. Our imaging system performs coherent anti-Stokes Raman scattering (CARS), stimulated Raman scattering (SRS), two-photon excitation fluorescence (TPEF), second-harmonic generation (SHG) and thermal imaging into a single platform that allows for unprecedented co-registration of thermal and biochemical information in real-time. Here, we present our work leveraging CARS and SRS in acute thalamocortical brain slice preparations. We observe the evolution of lipid and protein-specific Raman bands during INS and electrically evoked activity in real-time. Combined with two-photon fluorescence and second harmonic generation, we offer insight to cellular metabolism and membrane dynamics during INS. Thermal imaging allows for the coregistration of acquired biochemical information with temperature information. Our work previews the versatility and capabilities of coherent Raman imaging combined with multiphoton imaging to observe biophysical phenomena for neuroscience applications.

  17. One hertz repetitive transcranial magnetic stimulation over dorsal premotor cortex enhances offline motor memory consolidation for sequence-specific implicit learning.

    PubMed

    Meehan, S K; Zabukovec, J R; Dao, E; Cheung, K L; Linsdell, M A; Boyd, L A

    2013-10-01

    Consolidation of motor memories associated with skilled practice can occur both online, concurrent with practice, and offline, after practice has ended. The current study investigated the role of dorsal premotor cortex (PMd) in early offline motor memory consolidation of implicit sequence-specific learning. Thirty-three participants were assigned to one of three groups of repetitive transcranial magnetic stimulation (rTMS) over left PMd (5 Hz, 1 Hz or control) immediately following practice of a novel continuous tracking task. There was no additional practice following rTMS. This procedure was repeated for 4 days. The continuous tracking task contained a repeated sequence that could be learned implicitly and random sequences that could not. On a separate fifth day, a retention test was performed to assess implicit sequence-specific motor learning of the task. Tracking error was decreased for the group who received 1 Hz rTMS over the PMd during the early consolidation period immediately following practice compared with control or 5 Hz rTMS. Enhanced sequence-specific learning with 1 Hz rTMS following practice was due to greater offline consolidation, not differences in online learning between the groups within practice days. A follow-up experiment revealed that stimulation of PMd following practice did not differentially change motor cortical excitability, suggesting that changes in offline consolidation can be largely attributed to stimulation-induced changes in PMd. These findings support a differential role for the PMd in support of online and offline sequence-specific learning of a visuomotor task and offer converging evidence for competing memory systems. © 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  18. Safety and efficacy of repetitive transcranial magnetic stimulation in the treatment of depression: a critical appraisal of the last 10 years.

    PubMed

    Rachid, F; Bertschy, G

    2006-01-01

    Depression is a common and debilitating illness, for which alternative treatments are urgently needed. Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive and relatively painless experimental technique of altering brain physiology. The authors critically review the evidence for the efficacy, safety and tolerability of rTMS in the treatment of depression based on published data over the last decade. They also discuss studies which have examined relevant clinical, demographic, methodological, and technical parameters that might be implicated in optimizing the antidepressant efficacy of this technique. rTMS depression trials conducted through early 2006 are included in this review, which focuses mainly on the results of published sham-controlled studies, literature reviews and meta-analyses. Trials published so far have been characterized by the use of a great variety of stimulation parameters, study designs, questionable sham controls, small sample sizes and heterogeneously depressed populations, all of which have made comparisons between studies difficult. Meta-analyses of 2-week rTMS sham-controlled studies support, for the most part, the antidepressant effects of rTMS which are statistically superior to sham. However, the degree of clinical improvement remains small, although greater efficacy has been shown with longer treatment courses and predictors of response to rTMS are progressively being identified. rTMS is a promising antidepressant treatment with overall minor adverse effects. Because the clinical efficacy of rTMS as an antidepressant remains questionable, further systematic, large-scale multicenter studies comparing rTMS to a sham and/or to an antidepressant medication along with more stringent stimulation parameters are warranted in order to identify patient populations most likely to benefit and treatment parameters most likely to optimize its antidepressant efficacy.

  19. Two Versus One High-Frequency Repetitive Transcranial Magnetic Stimulation Session per Day for Treatment-Resistant Depression: A Randomized Sham-Controlled Trial.

    PubMed

    Theleritis, Christos; Sakkas, Pavlos; Paparrigopoulos, Thomas; Vitoratou, Silia; Tzavara, Chara; Bonaccorso, Stefania; Politis, Antonios; Soldatos, Constantin R; Psarros, Costantin

    2017-09-01

    High-frequency repetitive transcranial magnetic stimulation (HF-rTMS) has proven antidepressant effects, but the optimal frequency of sessions remains unclear. We conducted a 3-week, sham-controlled trial to assess the antidepressant efficacy of 1 active HF-rTMS session per day (A1 group) compared with 2 per day (A2 group) and equivalent sham sessions (once a day, S1 group; twice a day, S2 group) in patients with treatment-resistant major depression with a subsequent 2-week follow-up period. One hundred seventy-seven patients were screened, of whom 105 met eligibility criteria and 98 consented and were randomized. The HF-rTMS (20 Hz) was targeted to the left prefrontal cortex in sessions of approximately 40 trains (2 seconds each) at 100% resting motor threshold with an intertrain interval of 1 minute. Treatment response was defined as a 50% or greater decrease in the Hamilton Depression Rating Scale (HDRS) score and/or Clinician Global Impressions-Severity of Illness (CGI-S) score of 3 or less. Remission was defined as HDRS score less than 8 and/or CGI-S score of 2 or less. Practically none of the subjects in either sham groups achieved remission. Increased odds of remission were present for CGI-S by stimulating twice rather than once per day (odds ratio [OR] = 1.5, P = 0.018), whereas there was a marginal result for HDRS (OR = 3.9, P = 0.066). Patients who had lower baseline HDRS (OR = 0.75, P = 0.014) and CGI-S scores (OR = 0.18, P = 0.001) were more likely to achieve remission. Twice per day active HF-rTMS might be more effective than once per day active HF-rTMS or sham stimulation.

  20. Sucrose and naltrexone prevent increased pain sensitivity and impaired long-term memory induced by repetitive neonatal noxious stimulation: Role of BDNF and β-endorphin.

    PubMed

    Nuseir, Khawla Q; Alzoubi, Karem H; Alhusban, Ahmed; Bawaane, Areej; Al-Azzani, Mohammed; Khabour, Omar F

    2017-10-01

    Pain in neonates is associated with short and long-term adverse outcomes. Data demonstrated that long-term consequences of untreated pain are linked to the plasticity of the neonate's brain. Sucrose is effective and safe for reducing painful procedures from single events. However, the mechanism of sucrose-induced analgesia is not fully understood. The role of the opioid system in this analgesia using the opioid receptor antagonist Naltrexone was investigated, plus the long-term effects on learning and memory formation during adulthood. Pain was induced in rat pups via needle pricks of the paws. Sucrose solution and/or naltrexone were administered before the pricks. All treatments started on day one of birth and continued for two weeks. At the end of 8weeks, behavioral studies were conducted to test spatial learning and memory using radial arm water maze (RAWM), and pain threshold via foot-withdrawal response to a hot plate. The hippocampus was dissected; levels of brain derived neurotrophic factor (BDNF) and endorphins were assessed using ELISA. Acute repetitive neonatal pain increased pain sensitivity later in life, while naltrexone with sucrose decreased pain sensitivity. Naltrexone and/or sucrose prevented neonatal pain induced impairment of long-term memory, while neonatal pain decreased levels of BDNF in the hippocampus; this decrease was averted by sucrose and naltrexone. Sucrose with naltrexone significantly increased β-endorphin levels in noxiously stimulated rats. In conclusion, naltrexone and sucrose can reverse increased pain sensitivity and impaired long-term memory induced by acute repetitive neonatal pain probably by normalizing BDNF expression and increasing β-endorphin levels. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. The Impact of Accelerated Right Prefrontal High-Frequency Repetitive Transcranial Magnetic Stimulation (rTMS) on Cue-Reactivity: An fMRI Study on Craving in Recently Detoxified Alcohol-Dependent Patients

    PubMed Central

    Herremans, Sarah C.; Van Schuerbeek, Peter; De Raedt, Rudi; Matthys, Frieda; Buyl, Ronald; De Mey, Johan; Baeken, Chris

    2015-01-01

    In alcohol-dependent patients craving is a difficult-to-treat phenomenon. It has been suggested that high-frequency (HF) repetitive transcranial magnetic stimulation (rTMS) may have beneficial effects. However, exactly how this application exerts its effect on the underlying craving neurocircuit is currently unclear. In an effort to induce alcohol craving and to maximize detection of HF-rTMS effects to cue-induced alcohol craving, patients were exposed to a block and event-related alcohol cue-reactivity paradigm while being scanned with fMRI. Hence, we assessed the effect of right dorsolateral prefrontal cortex (DLPFC) stimulation on cue-induced and general alcohol craving, and the related craving neurocircuit. Twenty-six recently detoxified alcohol-dependent patients were included. First, we evaluated the impact of one sham-controlled stimulation session. Second, we examined the effect of accelerated right DLPFC HF-rTMS treatment: here patients received 15 sessions in an open label accelerated design, spread over 4 consecutive days. General craving significantly decreased after 15 active HF-rTMS sessions. However, cue-induced alcohol craving was not altered. Our brain imaging results did not show that the cue-exposure affected the underlying craving neurocircuit after both one and fifteen active HF-rTMS sessions. Yet, brain activation changes after one and 15 HF-rTMS sessions, respectively, were observed in regions associated with the extended reward system and the default mode network, but only during the presentation of the event-related paradigm. Our findings indicate that accelerated HF-rTMS applied to the right DLPFC does not manifestly affect the craving neurocircuit during an alcohol-related cue-exposure, but instead it may influence the attentional network. PMID:26295336

  2. Novel X-Ray Imaging Technology Allows Substantial Patient Radiation Reduction without Image Quality Impairment in Repetitive Transarterial Chemoembolization for Hepatocellular Carcinoma.

    PubMed

    Wen, Xiaofei; Jiang, Xianxian; Li, Renfei; Zhang, Junya; Yang, Po; Shen, Baozhong

    2015-11-01

    To assess patient radiation dose reduction and the image quality of a new X-ray imaging technology during repetitive transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). Fifty HCC patients (36 men; 57 ± 11 years) undergoing repetitive TACE were first randomly assigned to receive a TACE treatment on a reference X-ray system or a low-dose system with advanced real-time image processing. The alternate system was used for a repeated TACE (treatment interval, 0.5-6 months). Fluoroscopy time, number of digital subtraction angiography (DSA), air kerma (AK), and dose area product (DAP) were compared between the two systems and between the two repetitive TACE. Three interventional radiologists independently rated the image quality in blinded offline readings. Fluoroscopy time (8.7 ± 5.9 minutes vs. 8.7 ± 7.9 minutes, P = .981), numbers of DSA runs (6 ± 4 vs. 6 ± 4, P = .735), and exposure images (173 ± 86 vs. 168 ± 91, P = .916) were equivalent between the two systems. No statistical difference in X-ray usage was found between repeated treatments. Compared to the reference system, the technology significantly reduced AK and DAP by 48.6% (0.17 ± 0.13 Gy vs. 0.41 ± 0.36 Gy, P < .0001) and 50.3% (77.3 ± 55.2 Gy cm(2) vs. 195.0 ± 155.5 Gy cm(2), P < .0001), respectively. Image quality was rated comparable between the new system and the reference, with average scores of 3.9 ± 0.3 versus 4.4 ± 0.3 in fluoroscopy and 4.5 ± 0.2 versus 4.3 ± 0.3 in DSA. Patient radiation exposure can be substantially reduced by a factor of approximately two with the novel X-ray imaging technology while maintaining image quality. Copyright © 2015. Published by Elsevier Inc.

  3. Label-Free Neurosurgical Pathology with Stimulated Raman Imaging

    PubMed Central

    Lu, Fa-Ke; Calligaris, David; Olubiyi, Olutayo I.; Norton, Isaiah; Yang, Wenlong; Santagata, Sandro; Xie, X. Sunney; Golby, Alexandra J.; Agar, Nathalie Y. R.

    2016-01-01

    The goal of brain tumor surgery is to maximize tumor removal without injuring critical brain structures. Achieving this goal is challenging since it can be difficult to distinguish tumor from non-tumor tissue. While standard histopathology provides information that could assist tumor delineation, it cannot be performed iteratively during surgery as freezing, sectioning, and staining of the tissue require too much time. Stimulated Raman scattering (SRS) microscopy is a powerful label-free chemical imaging technology that enables rapid mapping of lipids and proteins within a fresh specimen. This information can be rendered into pathology-like images. Although this approach has been used to assess the density of glioma cells in murine orthotopic xenografts models and human brain tumors, tissue heterogeneity in clinical brain tumors has not yet been fully evaluated with SRS imaging. Here we profile 41 specimens resected from 12 patients with a range of brain tumors. By evaluating large-scale stimulated Raman imaging data and correlating this data with current clinical gold standard of histopathology for 4,422 fields of view, we capture many essential diagnostic hallmarks for glioma classification. Notably, in fresh tumor samples we observe additional features, not seen by conventional methods, including extensive lipid droplets within glioma cells, collagen deposition in gliosarcoma, and irregularity and disruption of myelinated fibers in areas infiltrated by oligodendroglioma cells. This data is freely available in a public resource to foster diagnostic training and to permit additional interrogation. Our work establishes the methodology and provides a significant collection of reference images for label-free neurosurgical pathology. PMID:27197198

  4. 100 Repetitions

    ERIC Educational Resources Information Center

    Benson, Jeffrey

    2012-01-01

    One hundred repetitions--100 "useful" repetitions. This notion has guided the author's work in alternative education programs for almost 20 years, dealing with the most challenging students, from addicts to conduct-disordered adolescents to traumatized 5th graders. There are no magic tricks. The role of educators is to align with the healthy…

  5. 100 Repetitions

    ERIC Educational Resources Information Center

    Benson, Jeffrey

    2012-01-01

    One hundred repetitions--100 "useful" repetitions. This notion has guided the author's work in alternative education programs for almost 20 years, dealing with the most challenging students, from addicts to conduct-disordered adolescents to traumatized 5th graders. There are no magic tricks. The role of educators is to align with the healthy…

  6. Microseismic reflection imaging using data from a hydraulic reservoir stimulation

    NASA Astrophysics Data System (ADS)

    Reshetnikov, A.; Kummerow, J.; Shapiro, S. A.; Asanuma, H.; Häring, M.

    2012-12-01

    In this work we present an approach which uses waveforms from induced seismicity to build a detailed high resolution image of a stimulated reservoir. The idea of Microseismic Reflection Imaging (MRI) is to treat a located microseismic event as an active seismic source and to use migration techniques adapted from reflection seismics. We apply the MRI approach to high quality microseismic data from the stimulation of Enhanced Geothermal System at Basel, Switzerland. Microseismic waveforms were recorded at 6 borehole instruments between 2 and 6 km away from the injection point. We consider precisely located microseismic cloud which consists of than 2000 events including more than 1000 multiplets. For imaging we use the Fresnel-Volume-Migration method. This is a directional migration approach which uses wavefield polarization to restrict the migration operator to a region around the actual reflection point. It helps to reduce migration artifacts caused by limited aperture. To obtain polarization of the wavefield, we use auto- and cross-variances of time samples within a time window, including several dominant periods of the P- or S-wave. We also use a hodogram linearity threshold value to exclude parts of the seismograms with unreliable polarity estimates. We migrate both PP and SS reflections data recorded at 5 different sensors. Though the image quality degrades with increasing distance between the stimulated volume and receiver, resulting images complement each other and represent a detailed high resolution reflectivity map within the reservoir. The overall shape of the reflectors is in a good agreement with the shape of the microseismic cloud. We provide a joint interpretation of obtained images and event locations. Reflectors probably are cracks with a higher permeability compared to the background rock. These first order fractures serve as pathways for fluid and elevated pressure to the medium and therefore control the shape of the cloud. The majority of

  7. Low-Frequency Repetitive Transcranial Magnetic Stimulation (rTMS) Modulates Evoked-Gamma Frequency Oscillations in Autism Spectrum Disorder (ASD)

    PubMed Central

    Baruth, Joshua M.; Casanova, Manuel F.; El-Baz, Ayman; Horrell, Tim; Mathai, Grace; Sears, Lonnie; Sokhadze, Estate

    2010-01-01

    Introduction It has been reported that individuals with Autism Spectrum Disorder (ASD) have abnormal reactions to the sensory environment and visuo-perceptual abnormalities. Electrophysiological research has provided evidence that gamma band activity (30-80 Hz) is a physiological indicator of the co-activation of cortical cells engaged in processing visual stimuli and integrating different features of a stimulus. A number of studies have found augmented and indiscriminative gamma band power at early stages of visual processing in ASD; this may be related to decreased inhibitory processing and an increase in the ratio of cortical excitation to inhibition. Low frequency or ‘slow’ (≤1HZ) repetitive transcranial magnetic stimulation (rTMS) has been shown to increase inhibition of stimulated cortex by the activation of inhibitory circuits. Methods We wanted to test the hypothesis of gamma band abnormalities at early stages of visual processing in ASD by investigating relative evoked (i.e. ~ 100 ms) gamma power in 25 subjects with ASD and 20 age-matched controls using Kanizsa illusory figures. Additionally, we wanted to assess the effects of 12 sessions of bilateral ‘slow’ rTMS to the dorsolateral prefrontal cortex (DLPFC) on evoked gamma activity using a randomized controlled design. Results In individuals with ASD evoked gamma activity was not discriminative of stimulus type, whereas in controls early gamma power differences between target and non-target stimuli were highly significant. Following rTMS individuals with ASD showed significant improvement in discriminatory gamma activity between relevant and irrelevant visual stimuli. We also found significant improvement in the responses on behavioral questionnaires (i.e., irritability, repetitive behavior) as a result of rTMS. Conclusion We proposed that ‘slow’ rTMS may have increased cortical inhibitory tone which improved discriminatory gamma activity at early stages of visual processing. rTMS has the

  8. L-propionylcarnitine does not affect myocardial metabolic or functional response to chronotropic and inotropic stimulation after repetitive ischemia in anesthetized pigs.

    PubMed

    Duncker, D J; Sassen, L M; Bartels, G L; van Meegen, J R; McFalls, E O; Krams, R; Bezstarosti, K; Lamers, J M; Verdouw, P D

    1993-09-01

    .056) of baseline, respectively, probably owing to a reduction in arterial blood pressure (BP), because L-propionylcarnitine prevented the increase in systemic vascular resistance produced by ischemia-reperfusion. L-Propionylcarnitine did not affect myocardial metabolic and contractile functional responses to chronotropic and inotropic stimulation. In a model of repetitive myocardial ischemia, L-propionylcarnitine prevents systemic vasoconstriction in response to ischemia and reperfusion and, probably as a result of the lower afterload, slightly ameliorates postischemic hypofunction, but loss of carnitine apparently does not play a role in myocardial hypofunction after brief repetitive ischemia and reperfusion in pigs.

  9. K-alpha x-ray source using high energy and high repetition rate laser system for phase contrast imaging

    NASA Astrophysics Data System (ADS)

    Serbanescu, Cristina; Fourmaux, Sylvain; Kieffer, Jean-Claude; Kincaid, Russell; Krol, Andrzej

    2009-08-01

    K-alpha x-ray sources from laser produced plasmas provide completely new possibilities for x-ray phase-contrast imaging applications. By tightly focusing intense femtosecond laser pulses onto a solid target, K-alpha x-ray pulses are generated through the interaction of energetic electrons created in the plasma with the bulk target. In this paper, we present a continuous and efficient Mo K-alpha x-ray source produced by a femtosecond laser system operating at 100 Hz repetition rate with maximum pulse energy of 110 mJ before compression. The source has x-ray conversion efficiency greater than 10-5 into K-alpha line emission. In preparation for phase contrast imaging applications, the size of the resultant K-alpha x-ray emission spot has been also characterized. The source exhibits sufficient spatial coherence to observe phase contrast. We observe a relatively small broadening of the K-alpha source size compared to the size of the laser beam itself. Detailed characterization of the source including the x-ray spectrum and the x-ray average yield along with phase contrast images of test objects will be presented.

  10. Elasticity reconstructive imaging by means of stimulated echo MRI.

    PubMed

    Chenevert, T L; Skovoroda, A R; O'Donnell, M; Emelianov, S Y

    1998-03-01

    A method is introduced to measure internal mechanical displacement and strain by means of MRI. Such measurements are needed to reconstruct an image of the elastic Young's modulus. A stimulated echo acquisition sequence with additional gradient pulses encodes internal displacements in response to an externally applied differential deformation. The sequence provides an accurate measure of static displacement by limiting the mechanical transitions to the mixing period of the simulated echo. Elasticity reconstruction involves definition of a region of interest having uniform Young's modulus along its boundary and subsequent solution of the discretized elasticity equilibrium equations. Data acquisition and reconstruction were performed on a urethane rubber phantom of known elastic properties and an ex vivo canine kidney phantom using <2% differential deformation. Regional elastic properties are well represented on Young's modulus images. The long-term objective of this work is to provide a means for remote palpation and elasticity quantitation in deep tissues otherwise inaccessible to manual palpation.

  11. Challenges in comparing the acute cognitive outcomes of high-frequency repetitive transcranial magnetic stimulation (HF-rTMS) vs. electroconvulsive therapy (ECT) in major depression: A systematic review.

    PubMed

    Kedzior, Karina Karolina; Schuchinsky, Maria; Gerkensmeier, Imke; Loo, Colleen

    2017-03-02

    The present study aimed to systematically compare the cognitive outcomes of high-frequency repetitive transcranial magnetic stimulation (HF-rTMS) and electroconvulsive therapy (ECT) in head-to-head studies with major depression (MDD) patients. A systematic literature search identified six studies with 219 MDD patients that were too heterogeneous to reliably detect meaningful differences in acute cognitive outcomes after ECT vs. HF-rTMS. Cognitive effects of brain stimulation vary depending on the timeframe and methods of assessment, stimulation parameters, and maintenance treatment. Thus, acute and longer-term differences in cognitive outcomes both need to be investigated at precisely defined timeframes and with similar instruments assessing comparable functions.

  12. A Patch-Based Method for Repetitive and Transient Event Detection in Fluorescence Imaging

    PubMed Central

    Boulanger, Jérôme; Gidon, Alexandre; Kervran, Charles; Salamero, Jean

    2010-01-01

    Automatic detection and characterization of molecular behavior in large data sets obtained by fast imaging in advanced light microscopy become key issues to decipher the dynamic architectures and their coordination in the living cell. Automatic quantification of the number of sudden and transient events observed in fluorescence microscopy is discussed in this paper. We propose a calibrated method based on the comparison of image patches expected to distinguish sudden appearing/vanishing fluorescent spots from other motion behaviors such as lateral movements. We analyze the performances of two statistical control procedures and compare the proposed approach to a frame difference approach using the same controls on a benchmark of synthetic image sequences. We have then selected a molecular model related to membrane trafficking and considered real image sequences obtained in cells stably expressing an endocytic-recycling trans-membrane protein, the Langerin-YFP, for validation. With this model, we targeted the efficient detection of fast and transient local fluorescence concentration arising in image sequences from a data base provided by two different microscopy modalities, wide field (WF) video microscopy using maximum intensity projection along the axial direction and total internal reflection fluorescence microscopy. Finally, the proposed detection method is briefly used to statistically explore the effect of several perturbations on the rate of transient events detected on the pilot biological model. PMID:20976222

  13. Low frequency repetitive transcranial magnetic stimulation of the left dorsolateral prefrontal cortex transiently increases cue-induced craving for methamphetamine: A preliminary study

    PubMed Central

    Li, Xingbao; Malcolm, Robert J.; Huebner, Kristina; Hanlon, Colleen A.; Taylor, Joseph J.; Brady, Kathleen T.; George, Mark S.; See, Ronald E.

    2014-01-01

    Background Repetitive transcranial magnetic stimulation (rTMS) can temporarily interrupt or facilitate activity in a focal brain region. Several lines of evidence suggest that rTMS of the dorsolateral prefrontal cortex (DLPFC) can affect processes involved in drug addiction. We hypothesized that a single session of low-frequency rTMS of the left DLPFC would modulate cue-induced craving for methamphetamine (MA) when compared to a sham rTMS session. Methods In this single-blind, sham-controlled crossover study, 10 non-treatment seeking MA-dependent users and 8 healthy controls were randomized to receive 15 min of sham and real (1 Hz) DLPFC rTMS in two experimental sessions separated by 1 h. During each rTMS session, participants were exposed to blocks of neutral cues and MA-associated cues. Participants rated their craving after each cue block. Results In MA users, real rTMS over the left DLPFC increased self-reported craving as compared to sham stimulation (17.86 ± 1.46 vs. 24.85 ± 1.57, p = 0.001). rTMS had no effect on craving in healthy controls. One Hertz rTMS of the left DLPFC was safe and tolerable for all participants. Conclusions Low frequency rTMS of the left DLPFC transiently increased cue-induced craving in MA participants. These preliminary results suggest that 1 Hz rTMS of the left DLPFC may increase craving by inhibiting the prefrontal cortex or indirectly activating subcortical regions involved in craving. PMID:24028801

  14. Repetitive transcranial magnetic stimulation improves open field locomotor recovery after low but not high thoracic spinal cord compression-injury in adult rats.

    PubMed

    Poirrier, Anne-Lise; Nyssen, Yves; Scholtes, Felix; Multon, Sylvie; Rinkin, Charline; Weber, Géraldine; Bouhy, Delphine; Brook, Gary; Franzen, Rachelle; Schoenen, Jean

    2004-01-15

    Electromagnetic fields are able to promote axonal regeneration in vitro and in vivo. Repetitive transcranial magnetic stimulation (rTMS) is used routinely in neuropsychiatric conditions and as an atraumatic method to activate descending motor pathways. After spinal cord injury, these pathways are disconnected from the spinal locomotor generator, resulting in most of the functional deficit. We have applied daily 10 Hz rTMS for 8 weeks immediately after an incomplete high (T4-5; n = 5) or low (T10-11; n = 6) thoracic closed spinal cord compression-injury in adult rats, using 6 high- and 6 low-lesioned non-stimulated animals as controls. Functional recovery of hindlimbs was assessed using the BBB locomotor rating scale. In the control group, the BBB score was significantly better from the 7th week post-injury in animals lesioned at T4-5 compared to those lesioned at T10-11. rTMS significantly improved locomotor recovery in T10-11-injured rats, but not in rats with a high thoracic injury. In rTMS-treated rats, there was significant positive correlation between final BBB score and grey matter density of serotonergic fibres in the spinal segment just caudal to the lesion. We propose that low thoracic lesions produce a greater functional deficit because they interfere with the locomotor centre and that rTMS is beneficial in such lesions because it activates this central pattern generator, presumably via descending serotonin pathways. The benefits of rTMS shown here suggest strongly that this non-invasive intervention strategy merits consideration for clinical trials in human paraplegics with low spinal cord lesions.

  15. Unilateral suppression of pharyngeal motor cortex to repetitive transcranial magnetic stimulation reveals functional asymmetry in the hemispheric projections to human swallowing.

    PubMed

    Mistry, Satish; Verin, Eric; Singh, Salil; Jefferson, Samantha; Rothwell, John C; Thompson, David G; Hamdy, Shaheen

    2007-12-01

    Inhibitory patterns of repetitive transcranial magnetic stimulation (rTMS) were applied to pharyngeal motor cortex in order to establish its role in modulating swallowing activity and provide evidence for functionally relevant hemispheric asymmetry. Healthy volunteers underwent single pulse TMS before and for 60 min after differing intensities of 1 Hz rTMS (n = 9, 6 male, 3 female, mean age 34 +/- 3 years) or theta burst stimulation (TBS) (n = 9, 6 male, 3 female, mean age 37 +/- 4 years). Electromyographic responses recorded from pharynx and hand were used as a measure of cortico-motor pathway excitability. Swallowing behaviour was then examined with a reaction time protocol, before and for up to 60 min after the most effective inhibitory protocol (1 Hz) applied to each hemisphere. Interventions were conducted on separate days and compared to sham using ANOVA. Only high intensity 1 Hz rTMS consistently suppressed pharyngeal motor cortex immediately and for up to 45 min (-34 +/- 7%, P < or = 0.001). Adjacent hand and contralateral pharyngeal motor cortex showed no change in response (-15 +/- 12%, P = 0.14 and 15 +/- 12%, P = 0.45, respectively). When used to unilaterally disrupt each hemisphere, rTMS to pharyngeal motor cortex with the stronger responses altered normal (-12 +/- 3%, P < or = 0.001) and fast (-9 +/- 4%, P < or = 0.009) swallow times, not seen following rTMS to the contralateral cortex or after sham. Thus, suppression of pharyngeal motor cortex to rTMS is intensity and frequency dependent, which when applied to each hemisphere reveals functionally relevant asymmetry in the motor control of human swallowing.

  16. Synergistic effects of noradrenergic modulation with atomoxetine and 10 Hz repetitive transcranial magnetic stimulation on motor learning in healthy humans

    PubMed Central

    2014-01-01

    Background Repetitive transcranial magnetic stimulation (rTMS) is able to induce changes in neuronal activity that outlast stimulation. The underlying mechanisms are not completely understood. They might be analogous to long-term potentiation or depression, as the duration of the effects seems to implicate changes in synaptic plasticity. Norepinephrine (NE) has been shown to play a crucial role in neuronal plasticity in the healthy and injured human brain. Atomoxetine (ATX) and other NE reuptake inhibitors have been shown to increase excitability in different systems and to influence learning processes. Thus, the combination of two facilitative interventions may lead to further increase in excitability and motor learning. But in some cases homeostatic metaplasticity might protect the brain from harmful hyperexcitability. In this study, the combination of 60 mg ATX and 10 Hz rTMS over the primary motor cortex was used to examine changes in cortical excitability and motor learning and to investigate their influence on synaptic plasticity mechanisms. Results The results of this double-blind placebo-controlled study showed that ATX facilitated corticospinal and intracortical excitability in motor cortex. 10 Hertz rTMS applied during a motor task was able to further increase intracortical excitability only in combination with ATX. In addition, only the combination of 10 Hz rTMS and ATX was capable of enhancing the total number of correct responses and reaction time significantly, indicating an interaction effect between rTMS and ATX without signs of homeostatic metaplasticity. Conclusion These results suggest that pharmacologically enhanced NE transmission and 10 Hz rTMS exert a synergistic effect on motor cortex excitability and motor learning in healthy humans. PMID:24690416

  17. Repetitive transcranial magnetic stimulation of the primary motor cortex in the treatment of motor signs in Parkinson's disease: A quantitative review of the literature.

    PubMed

    Zanjani, Anosha; Zakzanis, Konstantine K; Daskalakis, Zafiris J; Chen, Robert

    2015-05-01

    Parkinson's disease (PD) is a progressive disorder characterized by the emergence of motor deficits. In light of the voluminous and conflicting findings in the literature, the aim of the present quantitative review was to examine the effects of repetitive transcranial magnetic stimulation (rTMS) targeting the primary motor cortex (M1) in the treatment of motor signs in PD. Studies meeting inclusion criteria were analyzed using meta-analytic techniques and the Unified Parkinson's Disease Rating Scale (UPDRS) sections II and III were used as outcome measures. In order to determine the treatment effects of rTMS, the UPDRS II and III scores obtained at baseline, same day, to 1 day post rTMS treatment (short-term follow-up) and 1-month post stimulation (long-term follow-up) were compared between the active and sham rTMS groups. Additionally, the placebo effect was evaluated as the changes in UPDRS III scores in the sham rTMS groups. A placebo effect was not demonstrated, because sham rTMS did not improve motor signs as measured by UPDRS III. Compared with sham rTMS, active rTMS targeting the M1 significantly improved UPDRS III scores at the short-term follow-up (Cohen's d of 0.27, UPDRS III score improvement of 3.8 points). When the long-term follow-up UPDRS III scores were compared with baseline scores, the standardized effect size between active and sham rTMS did not reach significance. However, this translated into a significant nonstandardized 6.3-point improvement on the UPDRS III. No significant improvement in the UPDRS II was found. rTMS over the M1 may improve motor signs. Further studies are needed to provide a definite conclusion.

  18. Safety of primed repetitive transcranial magnetic stimulation and modified constraint-induced movement therapy in a randomized controlled trial in pediatric hemiparesis.

    PubMed

    Gillick, Bernadette T; Krach, Linda E; Feyma, Tim; Rich, Tonya L; Moberg, Kelli; Menk, Jeremiah; Cassidy, Jessica; Kimberley, Teresa; Carey, James R

    2015-04-01

    To investigate the safety of combining a 6-Hz primed low-frequency repetitive transcranial magnetic stimulation (rTMS) intervention in the contralesional hemisphere with a modified constraint-induced movement therapy (mCIMT) program in children with congenital hemiparesis. Phase 1 randomized, double-blinded, placebo-controlled pretest/posttest trial. University academic facility and pediatric specialty hospital. Subjects (N = 19; age range, 8-17 y) with congenital hemiparesis caused by ischemic stroke or periventricular leukomalacia. No subject withdrew because of adverse events. All subjects included completed the study. Subjects were randomized to 1 of 2 groups: either real rTMS plus mCIMT (n = 10) or sham rTMS plus mCIMT (n = 9). Adverse events, physician assessment, ipsilateral hand function, stereognosis, cognitive function, subject report of symptoms assessment, and subject questionnaire. No major adverse events occurred. Minor adverse events were found in both groups. The most common events were headaches (real: 50%, sham: 89%; P = .14) and cast irritation (real: 30%, sham: 44%; P = .65). No differences between groups in secondary cognitive and unaffected hand motor measures were found. Primed rTMS can be used safely with mCIMT in congenital hemiparesis. We provide new information on the use of rTMS in combination with mCIMT in children. These findings could be useful in research and future clinical applications in advancing function in congenital hemiparesis. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  19. Bilateral repetitive transcranial magnetic stimulation for treatment-resistant depression: a systematic review and meta-analysis of randomized controlled trials

    PubMed Central

    Zhang, Y.Q.; Zhu, D.; Zhou, X.Y.; Liu, Y.Y.; Qin, B.; Ren, G.P.; Xie, P.

    2015-01-01

    There has been concern regarding the use of controversial paradigms for repetitive transcranial magnetic stimulation (rTMS) to manage treatment-resistant depression (TRD). This meta-analysis assessed the efficacy of bilateral rTMS compared with unilateral and sham rTMS in patients with TRD. PubMed, Embase, CENTRAL, PsycINFO, Web of Science, EAGLE and NTIS databases were searched to identify relevant studies, and randomized controlled trials (RCTs) on bilateral rTMS for TRD patients were included. The response was defined as the primary outcome, and remission was the secondary outcome. Ten RCTs that included 634 patients met the eligibility criteria. The risk ratio (RRs) of both the primary and secondary outcomes of bilateral rTMS showed non-significant increases compared to unilateral rTMS (RR=1.01, P=0.93; odds ratio [OR]=0.77, P=0.22). Notably, the RR of the primary bilateral rTMS outcome was significantly increased compared to that for sham rTMS (RR=3.43, P=0.0004). The results of our analysis demonstrated that bilateral rTMS was significantly more effective than sham rTMS but not unilateral rTMS in patients with TRD. Thus, bilateral rTMS may not be a useful paradigm for patients with TRD. PMID:25590350

  20. Bilateral repetitive transcranial magnetic stimulation for treatment-resistant depression: a systematic review and meta-analysis of randomized controlled trials.

    PubMed

    Zhang, Y Q; Zhu, D; Zhou, X Y; Liu, Y Y; Qin, B; Ren, G P; Xie, P

    2015-03-01

    There has been concern regarding the use of controversial paradigms for repetitive transcranial magnetic stimulation (rTMS) to manage treatment-resistant depression (TRD). This meta-analysis assessed the efficacy of bilateral rTMS compared with unilateral and sham rTMS in patients with TRD. PubMed, Embase, CENTRAL, PsycINFO, Web of Science, EAGLE and NTIS databases were searched to identify relevant studies, and randomized controlled trials (RCTs) on bilateral rTMS for TRD patients were included. The response was defined as the primary outcome, and remission was the secondary outcome. Ten RCTs that included 634 patients met the eligibility criteria. The risk ratio (RRs) of both the primary and secondary outcomes of bilateral rTMS showed non-significant increases compared to unilateral rTMS (RR=1.01, P=0.93; odds ratio [OR]=0.77, P=0.22). Notably, the RR of the primary bilateral rTMS outcome was significantly increased compared to that for sham rTMS (RR=3.43, P=0.0004). The results of our analysis demonstrated that bilateral rTMS was significantly more effective than sham rTMS but not unilateral rTMS in patients with TRD. Thus, bilateral rTMS may not be a useful paradigm for patients with TRD.

  1. Changes in negative symptoms and EEG in schizophrenic patients after repetitive transcranial magnetic stimulation (rTMS): an open-label pilot study.

    PubMed

    Jandl, M; Bittner, R; Sack, A; Weber, B; Günther, T; Pieschl, D; Kaschka, W-P; Maurer, K

    2005-07-01

    The effects of repetitive transcranial magnetic stimulation (rTMS) on schizophrenic negative symptoms (NS) and EEG topography were investigated in this pilot study. 10 patients with predominant NS were treated with 10 Hz rTMS over the left dorsolateral prefrontal cortex for 5 days. For NS ratings, the Scale for the Assessment of Negative Symptoms (SANS) was used. Both ratings and EEG recordings were obtained pre- and post-rTMS. Electrical activity changes were computed by Low Resolution Brain Electromagnetic Tomography. SANS showed an improvement after rTMS, from 49.0 (SD: 10.7) to 44.7 (SD: 11.8) (means). EEG frequency bands were changed fronto-temporally (right) and were mainly decreases in delta- and beta- and increases in alpha1-activity, as well as decreases in beta-activity in the temporal and parieto-occipital regions (left). Although we are aware of the limitations of this study, we assume a slight improvement in NS. The EEG findings refer to a possible neurophysiologic correlate of their improvement after rTMS.

  2. Repetitive Transcranial Magnetic Stimulation Improved Symptoms of Obsessive-Compulsive Disorders but Not Executive Functions: Results from a Randomized Clinical Trial with Crossover Design and Sham Condition.

    PubMed

    Shayganfard, Mehran; Jahangard, Leila; Nazaribadie, Marzieh; Haghighi, Mohammad; Ahmadpanah, Mohammad; Sadeghi Bahmani, Dena; Bajoghli, Hafez; Holsboer-Trachsler, Edith; Brand, Serge

    2016-01-01

    Whereas there is growing evidence that repetitive transcranial magnetic stimulation (rTMS) favorably impacts on symptoms of obsessive-compulsive disorders (OCD), less is known regarding the influence of rTMS on cognitive performance of patients with OCD. Here, we tested the hypothesis that rTMS has a positive impact both on symptom severity and executive functions in such patients. We assessed 10 patients diagnosed with OCD (mean age: 33.5 years) and treated with a standard medication; they were randomly assigned either to a treatment-first or to a sham-first condition. Symptom severity (experts' ratings) and executive functions (Wisconsin Card Sorting Test) were assessed by independent raters unaware of the patients' group assignments at baseline, after 2 and 4 weeks. After 2 weeks, treatment switched to sham condition, and sham condition switched to treatment condition. Under treatment but not under sham conditions, symptom severity decreased. Performance on the executive function test increased continuously with every new assessment and was unrelated to rTMS treatment. Whereas the present study confirmed previous research suggesting that rTMS improved symptoms of OCD, rTMS did not improve executive functions to a greater degree than sham treatment. More research is needed to investigate the effect of rTMS on executive functions in patients with OCD. © 2017 S. Karger AG, Basel.

  3. Mechanism of functional recovery after repetitive transcranial magnetic stimulation (rTMS) in the subacute cerebral ischemic rat model: neural plasticity or anti-apoptosis?

    PubMed

    Yoon, Kyung Jae; Lee, Yong-Taek; Han, Tai Ryoon

    2011-10-01

    Repetitive transcranial magnetic stimulation (rTMS) has been studied increasingly in recent years to determine whether it has a therapeutic benefit on recovery after stroke. However, the underlying mechanisms of rTMS in stroke recovery remain unclear. Here, we evaluated the effect of rTMS on functional recovery and its underlying mechanism by assessing proteins associated with neural plasticity and anti-apoptosis in the peri-lesional area using a subacute cerebral ischemic rat model. Twenty cerebral ischemic rats were randomly assigned to the rTMS or the sham group at post-op day 4. A total of 3,500 impulses with 10 Hz frequency were applied to ipsilesional cortex over a 2-week period. Functional outcome was measured before (post-op day 4) and after rTMS (post-op day 18). The rTMS group showed more functional improvement on the beam balance test and had stronger Bcl-2 and weaker Bax expression on immunohistochemistry compared with the sham group. The expression of NMDA and MAP-2 showed no significant difference between the two groups. These results suggest that rTMS in subacute cerebral ischemia has a therapeutic effect on functional recovery and is associated with an anti-apoptotic mechanism in the peri-ischemic area rather than with neural plasticity.

  4. Repetitive Transcranial Magnetic Stimulation Changes Cerebral Oxygenation on the Left Dorsolateral Prefrontal Cortex in Bulimia Nervosa: A Near-Infrared Spectroscopy Pilot Study.

    PubMed

    Sutoh, Chihiro; Koga, Yasuko; Kimura, Hiroshi; Kanahara, Nobuhisa; Numata, Noriko; Hirano, Yoshiyuki; Matsuzawa, Daisuke; Iyo, Masaomi; Nakazato, Michiko; Shimizu, Eiji

    2016-01-01

    Previous studies showed that food craving in eating disorders can be weakened with high-frequency repetitive transcranial magnetic stimulation (rTMS) on the left dorsolateral prefrontal cortex (DLPFC). The aims of this study were to assess cerebral oxygenation change induced with rTMS and to assess the short-term impact of rTMS on food craving and other bulimic symptoms in patients with bulimia nervosa (BN). Eight women diagnosed with BN according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision criteria participated in this study. We measured haemoglobin concentration changes in the DLPFC with near-infrared spectroscopy during cognitive tasks measuring self-regulatory control in response to food photo stimuli, both at baseline and after a single session of rTMS. Subjective ratings for food cravings demonstrated significant reduction. A significant decrease in cerebral oxygenation of the left DLPFC was also observed after a single session of rTMS. Measurement with NIRS after rTMS intervention may be applicable for discussing the mechanisms underlying rTMS modulation in patients with BN.

  5. QEEG Theta Cordance in the Prediction of Treatment Outcome to Prefrontal Repetitive Transcranial Magnetic Stimulation or Venlafaxine ER in Patients With Major Depressive Disorder.

    PubMed

    Bares, Martin; Brunovsky, Martin; Novak, Tomas; Kopecek, Miloslav; Stopkova, Pavla; Sos, Peter; Höschl, Cyril

    2015-04-01

    The aims of this double-blind study were to assess and compare the efficacy of quantitative electroencephalographic (QEEG) prefrontal theta band cordance in the prediction of response to 4-week, right, prefrontal, 1-Hz repetitive transcranial magnetic stimulation (rTMS) or venlafaxine ER in patients with major depressive disorder (MDD). Prefrontal QEEG cordance values of 50 inpatients (25 subjects in each group) completing 4 weeks of the study were obtained at baseline and after 1 week of treatment. Depressive symptoms were assessed using Montgomery-Åsberg Depression Rating Scale (MADRS) at baseline and at week 1 and 4. Treatment response was defined as a ≥50% reduction in baseline MADRS total score. All responders (n = 9) and 6 of 16 nonresponders in the rTMS group had reduced cordance at week 1 (P < .01). Reduction of theta cordance value at week 1 was detected in all responders (n = 10) to venlafaxine ER, but only in 4 of 15 nonresponders (P = .005). The comparison of the areas under the curve of cordance change for prediction of response between rTMS (0.75) and venlafaxine ER (0.89) treated groups yielded no significant difference (P = .27). Our study indicates that prefrontal QEEG cordance is a promising tool not only for predicting the response to certain antidepressants but also to rTMS treatment, with comparable predictive efficacy for both therapeutic interventions. © EEG and Clinical Neuroscience Society (ECNS) 2014.

  6. Does a combined intervention program of repetitive transcranial magnetic stimulation and intensive occupational therapy affect cognitive function in patients with post-stroke upper limb hemiparesis?

    PubMed Central

    Hara, Takatoshi; Abo, Masahiro; Kakita, Kiyohito; Masuda, Takeshi; Yamazaki, Ryunosuke

    2016-01-01

    Low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) to the contralesional hemisphere and intensive occupational therapy (iOT) have been shown to contribute to a significant improvement in upper limb hemiparesis in patients with chronic stroke. However, the effect of the combined intervention program of LF-rTMS and iOT on cognitive function is unknown. We retrospectively investigated whether the combined treatment influence patient's Trail-Making Test part B (TMT-B) performance, which is a group of easy and inexpensive neuropsychological tests that evaluate several cognitive functions. Twenty-five patients received 11 sessions of LF-rTMS to the contralesional hemisphere and 2 sessions of iOT per day over 15 successive days. Patients with right- and left-sided hemiparesis demonstrated significant improvements in upper limb motor function following the combined intervention program. Only patients with right-sided hemiparesis exhibited improved TMT-B performance following the combined intervention program, and there was a significant negative correlation between Fugl-Meyer Assessment scale total score change and TMT-B performance. The results indicate the possibility that LF-rTMS to the contralesional hemisphere combined with iOT improves the upper limb motor function and cognitive function of patients with right-sided hemiparesis. However, further studies are necessary to elucidate the mechanism of improved cognitive function. PMID:28197189

  7. The clinical utility of repetitive transcranial magnetic stimulation in reducing the risks of transitioning from acute to chronic pain in traumatically injured patients.

    PubMed

    Jodoin, Marianne; Rouleau, Dominique; Larson-Dupuis, Camille; Gosselin, Nadia; De Beaumont, Louis

    2017-07-08

    Pain is a multifaceted condition and a major ongoing challenge for healthcare professionals having to treat patients in whom pain put them at risk of developing other conditions. Significant efforts have been invested in both clinical and research settings in an attempt to demystify the mechanisms at stake and develop optimal treatments as well as to reduce individual and societal costs. It is now universally accepted that neuroinflammation and central sensitization are two key underlying factors causing pain chronification as they result from maladaptive central nervous system plasticity. Recent research has shown that the mechanisms of action of repetitive transcranial magnetic stimulation (rTMS) make it a particularly promising avenue in treating various pain conditions. This review will first discuss the contribution of neuroinflammation and central sensitization in the transition from acute to chronic pain in traumatically injured patients. A detailed discussion on how rTMS may allow the restoration from maladaptive plasticity in addition to breaking down the chain of events leading to pain chronification will follow. Lastly, this review will provide a theoretical framework of what might constitute optimal rTMS modalities in dealing with pain symptoms in traumatically injured patients based on an integrated perspective of the physiopathological mechanisms underlying pain. Copyright © 2017. Published by Elsevier Inc.

  8. Does a combined intervention program of repetitive transcranial magnetic stimulation and intensive occupational therapy affect cognitive function in patients with post-stroke upper limb hemiparesis?

    PubMed

    Hara, Takatoshi; Abo, Masahiro; Kakita, Kiyohito; Masuda, Takeshi; Yamazaki, Ryunosuke

    2016-12-01

    Low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) to the contralesional hemisphere and intensive occupational therapy (iOT) have been shown to contribute to a significant improvement in upper limb hemiparesis in patients with chronic stroke. However, the effect of the combined intervention program of LF-rTMS and iOT on cognitive function is unknown. We retrospectively investigated whether the combined treatment influence patient's Trail-Making Test part B (TMT-B) performance, which is a group of easy and inexpensive neuropsychological tests that evaluate several cognitive functions. Twenty-five patients received 11 sessions of LF-rTMS to the contralesional hemisphere and 2 sessions of iOT per day over 15 successive days. Patients with right- and left-sided hemiparesis demonstrated significant improvements in upper limb motor function following the combined intervention program. Only patients with right-sided hemiparesis exhibited improved TMT-B performance following the combined intervention program, and there was a significant negative correlation between Fugl-Meyer Assessment scale total score change and TMT-B performance. The results indicate the possibility that LF-rTMS to the contralesional hemisphere combined with iOT improves the upper limb motor function and cognitive function of patients with right-sided hemiparesis. However, further studies are necessary to elucidate the mechanism of improved cognitive function.

  9. Does Therapeutic Repetitive Transcranial Magnetic Stimulation Cause Cognitive Enhancing Effects in Patients with Neuropsychiatric Conditions? A Systematic Review and Meta-Analysis of Randomised Controlled Trials.

    PubMed

    Martin, Donel M; McClintock, Shawn M; Forster, Jane; Loo, Colleen K

    2016-09-01

    Repetitive transcranial magnetic stimulation (rTMS) is increasingly used as a therapeutic intervention for neuropsychiatric illnesses and has demonstrated efficacy for treatment of major depression. However, an unresolved question is whether a course of rTMS treatment results in effects on cognitive functioning. In this systematic review and meta-analysis we aimed to quantitatively determine whether a course of rTMS has cognitive enhancing effects. We examined cognitive outcomes from randomised, sham-controlled studies conducted in patients with neuropsychiatric conditions where rTMS was administered to the dorsolateral prefrontal cortex (DLPFC) across repeated sessions, searched from PubMed/MEDLINE and other databases up until October 2015. Thirty studies met our inclusion criteria. Cognitive outcomes were pooled and examined across the following domains: Global cognitive function, executive function, attention, working memory, processing speed, visual memory, verbal memory and visuospatial ability. Active rTMS treatment was unassociated with generalised gains across the majority of domains of cognitive functioning examined. Secondary analyses revealed a moderate sized positive effect for improved working memory in a small number of studies in patients with schizophrenia (k = 3, g = 0.507, 95 % CI = [0.183-0.831], p < .01). Therapeutic rTMS when administered to the DLPFC in patients with neuropsychiatric conditions does not result in robust cognitive enhancing effects.

  10. Are neuroticism and extraversion associated with the antidepressant effects of repetitive transcranial magnetic stimulation (rTMS)? An exploratory 4-week trial.

    PubMed

    Berlim, Marcelo T; McGirr, Alexander; Beaulieu, Marie-Martine; Van den Eynde, Frederique; Turecki, Gustavo

    2013-02-08

    Several randomized, controlled trials have found high frequency repetitive transcranial magnetic stimulation (HF-rTMS) to be effective for treating major depressive disorder (MDD), but its antidepressant mechanisms have yet to be firmly understood. In this context, pre-treatment personality traits and subsequent changes in personality concomitant to treatment may be relevant for our understanding of these mechanisms. To investigate this issue we conducted a naturalistic trial in which 14 subjects with moderate to severe depression were treated with daily HF-rTMS over the left dorsolateral prefrontal cortex for 4 weeks. Objective depressive symptoms (as assessed by the HAM-D(21)) and the major personality dimensions of neuroticism and extraversion were measured pre-post HF-rTMS. Pre-rTMS levels of extraversion predicted subsequent decrease in depressive symptoms. Also, HF-rTMS treatment resulted in a decrease in neuroticism scores, and this relative decrease was associated with the relative decrease in depression. Our results suggest that HF-rTMS may positively affect the personality dimension of neuroticism. Also, pre-treatment levels of extraversion may predict the subsequent antidepressant response to HF-rTMS. However, further studies with larger samples and controlled designs are needed to better clarify these preliminary findings.

  11. Increased facilitation of the primary motor cortex following 1 Hz repetitive transcranial magnetic stimulation of the contralateral cerebellum in normal humans.

    PubMed

    Oliveri, Massimiliano; Koch, Giacomo; Torriero, Sara; Caltagirone, Carlo

    2005-03-16

    Connections between the cerebellum and the contralateral motor cortex are dense and important, but their physiological significance is difficult to measure in humans. We have studied a group of 10 healthy subjects to test whether a modulation of the excitability of the left cerebellum can affect the excitability of the contralateral motor cortex. We used repetitive transcranial magnetic stimulation (rTMS) at 1 Hz frequency to transiently depress the excitability of the left cerebellar cortex and paired-pulse TMS testing of intracortical inhibition (ICI) and intracortical facilitation (ICF) to probe the excitability of cortico-cortical connections in the right motor cortex. The cortical silent period was also measured before and after cerebellar rTMS. Motor evoked potentials (MEPs) were significantly larger after than before conditioning rTMS trains (p < 0.01). Moreover, left cerebellar rTMS increased the ICF of the right motor cortex as measured with paired-pulses separated by an interstimulus interval (ISI) of 15 ms. The effect lasted for up to 30 min afterward and was specific for the contralateral (right) motor cortex. The cortical silent period was unaffected by cerebellar rTMS. The implication is that rTMS of the cerebellar cortex can shape the flowing of inhibition from Purkinje cells toward deep nuclei, thereby increasing the excitability of interconnected brain areas.

  12. Functional inhibition of the human middle temporal cortex affects non-visual motion perception: a repetitive transcranial magnetic stimulation study during tactile speed discrimination.

    PubMed

    Ricciardi, Emiliano; Basso, Demis; Sani, Lorenzo; Bonino, Daniela; Vecchi, Tomaso; Pietrini, Pietro; Miniussi, Carlo

    2011-02-01

    The visual motion-responsive middle temporal complex (hMT+) is activated during tactile and aural motion discrimination in both sighted and congenitally blind individuals, suggesting a supramodal organization of this area. Specifically, non-visual motion processing has been found to activate the more anterior portion of the hMT+. In the present study, repetitive transcranial magnetic stimulation (rTMS) was used to determine whether this more anterior portion of hMT+ truly plays a functional role in tactile motion processing. Sixteen blindfolded, young, healthy volunteers were asked to detect changes in the rotation velocity of a random Braille-like dot pattern by using the index or middle finger of their right hand. rTMS was applied for 600 ms (10 Hz, 110% motor threshold), 200 ms after the stimulus onset with a figure-of-eight coil over either the anterior portion of hMT+ or a midline parieto-occipital site (as a control). Accuracy and reaction times were significantly impaired only when TMS was applied on hMT+, but not on the control area. These results indicate that the recruitment of hMT+ is necessary for tactile motion processing, and thus corroborate the hypothesis of a 'supramodal' functional organization for this sensory motion processing area.

  13. Self-harm and suicidal acts: a suitable case for treatment of impulsivity-driven behaviour with repetitive transcranial magnetic stimulation (rTMS).

    PubMed

    Tracy, Derek K; Shergill, Sukhwinder S; David, Anthony S; Fonagy, Peter; Zaman, Rashid; Downar, Jonathan; Eliott, Emma; Bhui, Kamaldeep

    2015-06-01

    Suicidal thinking, self-harm and suicidal acts are common, although determining their precise prevalence is complex. Epidemiological work has identified a number of associated demographic and clinical factors, though, with the exception of past acts of self-harm, these are non-specific and weak future predictors. There is a critical need shift focus from managing 'suicidality-by-proxy' through general mental health treatments, to better understand the neuropsychology and neurophysiology of such behaviour to guide targeted interventions. The model of the cognitive control of emotion (MCCE) offers such a paradigm, with an underlying pan-diagnostic pathophysiology of a hypoactive prefrontal cortex failing to suitably inhibit an overactive threat-responding limbic system. The result is a phenotype - from any number of causative gene-environment interactions - primed to impulsively self-harm. We argue that such neural dysconnectivity is open to potential therapeutic modification from repetitive transcranial magnetic stimulation (rTMS). The current evidence base for this is undoubtedly extremely limited, but the societal and clinical burden self-harm and suicide pose warrants such investigation. K.B. is the Editor of BJPsych Open, but had no editorial involvement in the review or decision process regarding this paper. © The Royal College of Psychiatrists 2015. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) licence.

  14. Long-term Effectiveness of Modified Electroconvulsive Therapy Compared With Repetitive Transcranial Magnetic Stimulation for the Treatment of Recurrent Major Depressive Disorder.

    PubMed

    Jin, Xi-Long; Xu, Wei-Qin; Le, Ya-Juan; Dai, Xiong-Kai

    2016-06-01

    This retrospective study recruited 150 patients with recurrent major depressive disorder (MDD) who received modified electroconvulsive therapy (MECT) and 150 cases treated with repetitive transcranial magnetic stimulation (rTMS), which aimed to compare the short- and long-term effectiveness, as well as economic outcomes, of MECT and rTMS with a large sample size in patients with recurrent MDD. The results showed that the response rate of patients in the rTMS group was lower than that in the MECT group (46.0% vs 58.7%, p < 0.05). Patients in the rTMS group had elevated rate of dizziness, but reduced rates of poor memory and headache, as well as lower costs compared with the MECT group (p < 0.05). Importantly, we found that the relapse-free survival of patients was similar between the rTMS and MECT groups in the long term. In conclusion, rTMS is an alternative method for MECT in the treatment of patients with recurrent MDD.

  15. The use of repetitive transcranial magnetic stimulation for modulating craving and addictive behaviours: a critical literature review of efficacy, technical and methodological considerations.

    PubMed

    Grall-Bronnec, M; Sauvaget, A

    2014-11-01

    Repetitive transcranial magnetic stimulation (rTMS) is a potential therapeutic intervention for the treatment of addiction. This critical review aims to summarise the recent developments with respect to the efficacy of rTMS for all types of addiction and related disorders (including eating disorders), and concentrates on the associated methodological and technical issues. The bibliographic search consisted of a computerised screening of the Medline and ScienceDirect databases up to December 2013. Criteria for inclusion were the target problem was an addiction, a related disorder, or craving; the intervention was performed using rTMS; and the study was a clinical trial. Of the potential 638 articles, 18 met the criteria for inclusion. Most of these (11 of the 18) supported the efficacy of rTMS, especially in the short term. In most cases, the main assessment criterion was the measurement of craving using a Visual Analogue Scale. The results are discussed with respect to the study limitations and, in particular, the many methodological and technical discrepancies that were identified. Key recommendations are provided.

  16. Self-harm and suicidal acts: a suitable case for treatment of impulsivity-driven behaviour with repetitive transcranial magnetic stimulation (rTMS)

    PubMed Central

    Shergill, Sukhwinder S.; David, Anthony S.; Fonagy, Peter; Zaman, Rashid; Downar, Jonathan; Eliott, Emma; Bhui, Kamaldeep

    2015-01-01

    Summary Suicidal thinking, self-harm and suicidal acts are common, although determining their precise prevalence is complex. Epidemiological work has identified a number of associated demographic and clinical factors, though, with the exception of past acts of self-harm, these are non-specific and weak future predictors. There is a critical need shift focus from managing ‘suicidality-by-proxy’ through general mental health treatments, to better understand the neuropsychology and neurophysiology of such behaviour to guide targeted interventions. The model of the cognitive control of emotion (MCCE) offers such a paradigm, with an underlying pan-diagnostic pathophysiology of a hypoactive prefrontal cortex failing to suitably inhibit an overactive threat-responding limbic system. The result is a phenotype – from any number of causative gene–environment interactions – primed to impulsively self-harm. We argue that such neural dysconnectivity is open to potential therapeutic modification from repetitive transcranial magnetic stimulation (rTMS). The current evidence base for this is undoubtedly extremely limited, but the societal and clinical burden self-harm and suicide pose warrants such investigation. Declaration of interest K.B. is the Editor of BJPsych Open, but had no editorial involvement in the review or decision process regarding this paper. Copyright and usage © The Royal College of Psychiatrists 2015. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) licence. PMID:27703728

  17. Improvements in symptoms following neuronavigated repetitive transcranial magnetic stimulation (rTMS) in severe and enduring anorexia nervosa: findings from two case studies.

    PubMed

    McClelland, Jessica; Bozhilova, Natali; Nestler, Steffen; Campbell, Iain C; Jacob, Shirabdi; Johnson-Sabine, Eric; Schmidt, Ulrike

    2013-11-01

    Advances in the treatment of anorexia nervosa (AN) are most likely to arise from targeted, brain-directed treatments, such as repetitive transcranial magnetic stimulation (rTMS). We describe findings from two individuals with treatment-resistant AN who received 19-20 sessions of neuronavigated, high frequency rTMS, applied to the left dorsolateral prefrontal cortex. Within-session measures assessed changes pre-rTMS, post-rTMS in subjective eating disorder (ED) experiences. Weight, ED symptoms and mood were assessed pre-treatment, post-treatment and at 1 month follow-up. In both cases, there was improvement in ED symptomatology and mood after 19-20 sessions of neuronavigated rTMS, and these changes persisted or continued to improve at follow-up. Within sessions, Patient A demonstrated a consistent reduction in subjective ED experiences, and Patient B a reduction in some ED related experiences. These findings suggest that rTMS has potential as an adjunct to the treatment of AN and deserves further study. Copyright © 2013 John Wiley & Sons, Ltd and Eating Disorders Association.

  18. Denoising Stimulated Raman Spectroscopic Images by Total Variation Minimization

    PubMed Central

    Liao, Chien-Sheng; Choi, Joon Hee; Zhang, Delong; Chan, Stanley H.; Cheng, Ji-Xin

    2016-01-01

    High-speed coherent Raman scattering imaging is opening a new avenue to unveiling the cellular machinery by visualizing the spatio-temporal dynamics of target molecules or intracellular organelles. By extracting signals from the laser at MHz modulation frequency, current stimulated Raman scattering (SRS) microscopy has reached shot noise limited detection sensitivity. The laser-based local oscillator in SRS microscopy not only generates high levels of signal, but also delivers a large shot noise which degrades image quality and spectral fidelity. Here, we demonstrate a denoising algorithm that removes the noise in both spatial and spectral domains by total variation minimization. The signal-to-noise ratio of SRS spectroscopic images was improved by up to 57 times for diluted dimethyl sulfoxide solutions and by 15 times for biological tissues. Weak Raman peaks of target molecules originally buried in the noise were unraveled. Coupling the denoising algorithm with multivariate curve resolution allowed discrimination of fat stores from protein-rich organelles in C. elegans. Together, our method significantly improved detection sensitivity without frame averaging, which can be useful for in vivo spectroscopic imaging. PMID:26955400

  19. Imaging Drug Delivery to Skin with Stimulated Raman Scattering Microscopy

    PubMed Central

    Saar, Brian G.; Contreras-Rojas, L. Rodrigo; Xie, X. Sunney; Guy, Richard H.

    2011-01-01

    Efficient drug delivery to the skin is essential for the treatment of major dermatologic diseases, such as eczema, psoriasis and acne. However, many compounds penetrate the skin barrier poorly and require optimized formulations to ensure their bioavailability. Here, stimulated Raman scattering (SRS) microscopy, a recently-developed, label-free chemical imaging tool, is used to acquire high resolution images of multiple chemical components of a topical formulation as it penetrates into mammalian skin. This technique uniquely provides label-free, non-destructive, three-dimensional images with high spatiotemporal resolution. It reveals novel features of (trans)dermal drug delivery in the tissue environment: different rates of drug penetration via hair follicles as compared to the intercellular pathway across the stratum corneum are directly observed, and the precipitation of drug crystals on the skin surface is visualized after the percutaneous penetration of the co-solvent excipient in the formulation. The high speed three-dimensional imaging capability of SRS thus reveals features that cannot be seen with other techniques, providing both kinetic information and mechanistic insight into the (trans)dermal drug delivery process. PMID:21548600

  20. Two-photon imaging with 80 MHz and 1-GHz repetition rate Ti:sapphire oscillators

    NASA Astrophysics Data System (ADS)

    Studier, Hauke; Breunig, Hans Georg; König, Karsten

    2010-02-01

    We report on multiphoton optical imaging with a laser scanning microscope (TauMapTM, Jenlab GmbH) in combination with two different excitation fs-lasers: a 80 MHz Ti:sapphire oscillator generating spectrally tunable 100 fs pulses and a 1 GHz Ti:sapphire oscillator producing ultra broadband 6 fs pulses. While the ultra-broadband pulses enable simultaneous excitation of several different types of fluorophores due their large spectral width, the 100 fs pulses are spectrally more selective and require tuning the center wavelength to cover the same excitation range. The wavelength selectivity was confirmed in measurements with microspheres with absorption maxima in the green and blue spectral region. Furthermore, the potential of both lasers for imaging of human skin is evaluated.

  1. Efficacy of rapid-rate repetitive transcranial magnetic stimulation in the treatment of depression: a systematic review and meta-analysis

    PubMed Central

    Couturier, Jennifer L.

    2005-01-01

    Objective To systematically review the literature pertaining to rapid-rate repetitive transcranial magnetic stimulation (rTMS) compared with sham therapy for the treatment of a major depressive episode in order to arrive at qualitative and quantitative conclusions about the efficacy of rapid-rate rTMS. Methods MEDLINE, the Cochrane Library, the metaRegister of Controlled Trials and abstracts from scientific meetings were searched for the years 1966 until July 2003. The search terms “transcranial magnetic stimulation” and “transcranial magnetic stimulation AND depression” were used. Eighty-seven randomized controlled trials investigating the efficacy of rTMS were referenced on MEDLINE. Nineteen of these involved treatment of a major depressive episode, and these were reviewed. Six met more specific inclusion criteria including the use of rapid-rate stimulation, application to the left dorsolateral prefrontal cortex, evaluation with the 21-item Hamilton Rating Scale for Depression (HAM-D) and use of an intent-to-treat analysis. Scores on the 21-item HAM-D after treatment and standard deviations were extracted from each article for treatment and control subjects. A random-effects model was chosen for the meta-analysis, and the weighted mean difference was used as a summary measure. Results Six studies that met the inclusion criteria were identified and included in the meta-analysis. Two of these reported a significantly greater improvement in mood symptoms in the treatment versus the sham group. When combined in the meta-analysis, the overall weighted mean difference was –1.1 (95% confidence interval –4.5 to 2.3), and the results of a test for heterogeneity were not significant (χ25 = 5.81, p = 0.33). Conclusions This meta-analysis suggests that rapid-rate rTMS is no different from sham treatment in major depression; however, the power within these studies to detect a difference was generally low. Randomized controlled trials with sufficient power to

  2. Revisiting the Potential of Alternating Repetition Time Balanced Steady-State Free Precession Imaging of the Abdomen at 3 T.

    PubMed

    Gurney-Champion, Oliver J; Nederveen, Aart J; Klaassen, Remy; Engelbrecht, Marc R; Bel, Arjan; van Laarhoven, Hanneke W M; Stoker, Jaap; Goncalves, Sonia I

    2016-09-01

    The aim was to investigate the value of optimized 3-dimensional alternating repetition time balanced steady-state free precession (ATR-SSFP), as an alternative to conventional segmented balanced steady-state free precession (bSSFP) with fat suppression prepulse (FS-bSSFP), in single breath-hold abdominal magnetic resonance imaging at 3 T. Bloch simulations were performed to determine the optimal flip angle (FA = 1-90 degrees) and τ (1-3) with respect to signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) between abdominal organs for ATR-SSFP. These were corroborated by phantom measurements for different T1/T2 values (5-47) as well as in a healthy volunteer. In addition, fat suppression efficiency was studied using phantom and volunteer measurements. The effect of resolution on image quality was studied in a healthy volunteer. Using the optimal settings, ATR-SSFP images as well as FS-bSSFP images were obtained in 15 pancreatic cancer patients. For 10 structures of interest, the signal ratio with respect to the pancreas was computed and compared between both sequences. Finally, 10 items on image quality (fat suppression, artifacts, and sharpness) and tissue conspicuity (ducts, vessels, and duodenum) were scored by 2 abdominal radiologists for both image sequences. The results of simulations, phantom measurements, and volunteer measurements showed that, considering scan time, fat suppression, and clinical relevance, the ideal settings for ATR-SSFP were as follows: τ = 3; TR1 = 3.46 milliseconds; radiofrequency phase cycling 0, 180, 180, 0 degrees; and FA = 13-16 degrees (highest SNR) and 24-26 degrees (highest CNR). The optimized feasible additional settings implemented for patient scans were FA = 18 degrees and resolution = 1.4 × 1.4 × 1.4 mm. In patients, the signal ratios of both ATR-SSFP and FS-bSSFP were comparable and had a T2-like contrast behavior, although more accentuated in ATR-SSFP. The ATR-SSFP scored significantly higher than FS-bSSFP for 9

  3. Continuous-Wave Stimulated Emission Depletion Microscope for Imaging Actin Cytoskeleton in Fixed and Live Cells

    PubMed Central

    Neupane, Bhanu; Jin, Tao; Mellor, Liliana F.; Loboa, Elizabeth G.; Ligler, Frances S.; Wang, Gufeng

    2015-01-01

    Stimulated emission depletion (STED) microscopy provides a new opportunity to study fine sub-cellular structures and highly dynamic cellular processes, which are challenging to observe using conventional optical microscopy. Using actin as an example, we explored the feasibility of using a continuous wave (CW)-STED microscope to study the fine structure and dynamics in fixed and live cells. Actin plays an important role in cellular processes, whose functioning involves dynamic formation and reorganization of fine structures of actin filaments. Frequently used confocal fluorescence and STED microscopy dyes were employed to image fixed PC-12 cells (dyed with phalloidin- fluorescein isothiocyante) and live rat chondrosarcoma cells (RCS) transfected with actin-green fluorescent protein (GFP). Compared to conventional confocal fluorescence microscopy, CW-STED microscopy shows improved spatial resolution in both fixed and live cells. We were able to monitor cell morphology changes continuously; however, the number of repetitive analyses were limited primarily by the dyes used in these experiments and could be improved with the use of dyes less susceptible to photobleaching. In conclusion, CW-STED may disclose new information for biological systems with a proper characteristic length scale. The challenges of using CW-STED microscopy to study cell structures are discussed. PMID:26393614

  4. Repetitive transcranial magnetic stimulation inhibits Sirt1/MAO-A signaling in the prefrontal cortex in a rat model of depression and cortex-derived astrocytes.

    PubMed

    Peng, Zheng-Wu; Xue, Fen; Zhou, Cui-Hong; Zhang, Rui-Guo; Wang, Ying; Liu, Ling; Sang, Han-Fei; Wang, Hua-Ning; Tan, Qing-Rong

    2017-09-25

    Repetitive transcranial magnetic stimulation (rTMS) is a useful monotherapy for depression or adjunctive therapy for resistant depression. However, the anti-depressive effects of different parameters and the underlying mechanisms remain unclear. Here, we aimed to assess the effect of rTMS with different parameters (1/5/10 Hz, 0.84/1.26 T) on the depressive-like behaviors, 5-hydroxytryptamine (5-HT), 5-HIAA (5-hydroxyindoleacetic acid) and DA and NE levels, and monoamine oxidase A (MAO-A) activity in chronic unpredictable stress-treated rats, along with the expression of sirtuin 1 (Sirt1) and MAO-A in the prefrontal cortex (PFC) and cortex-derived astrocytes from new-born rats. Moreover, the depressive-like behaviors were monitored following the transcranial injection of the Sirt1 inhibitor EX527 (1 mM) daily for 1 week. We found that rTMS treatment (5/10 Hz, 0.84/1.26 T) ameliorated depressive-like behaviors, increased 5-HT, DA and NE levels, decreased the 5-HIAA level and Sirt1 and MAO-A expression, and reduced MAO-A activity in the PFC. The depressive-like behaviors were also ameliorated after the transcranial injection of EX527. Importantly, rTMS (5/10 Hz, 0.84/1.26 T) inhibited Sirt1 and MAO-A expressions in astrocytes and Sirt1 knockdown with short hairpin RNA decreased MAO-A expression in astrocytes. These results suggest that the inhibition of Sirt1/MAO-A expression in astrocytes in the PFC may contribute to the different anti-depressive effects of rTMS with different parameters, and may also provide a novel insight into the mechanisms underlying major depressive disorder.

  5. Primed low-frequency repetitive transcranial magnetic stimulation and constraint-induced movement therapy in pediatric hemiparesis: a randomized controlled trial.

    PubMed

    Gillick, Bernadette T; Krach, Linda E; Feyma, Tim; Rich, Tonya L; Moberg, Kelli; Thomas, William; Cassidy, Jessica M; Menk, Jeremiah; Carey, James R

    2014-01-01

    The aim of this study was to determine the feasibility and efficacy of five treatments of 6 Hz primed, low-frequency, repetitive transcranial magnetic stimulation (rTMS) combined with constraint-induced movement therapy (CIMT) to promote recovery of the paretic hand in children with congenital hemiparesis. Nineteen children with congenital hemiparesis aged between 8 and 17 years (10 males, nine females; mean age 10 years 10 months, SD 2 years 10 months; Manual Ability Classification Scale levels I-III) underwent five sessions of either real rTMS (n=10) or sham rTMS (n=9) alternated daily with CIMT. CIMT consisted of 13 days of continuous long-arm casting with five skin-check sessions. Each child received a total of 10 hours of one-to-one therapy. The primary outcome measure was the Assisting Hand Assessment (AHA) and the secondary outcome variables were the Canadian Occupational Performance Measure (COPM) and stereognosis. A Wilcoxon signed-rank sum test was used to analyze differences between pre- and post-test scores within the groups. Analysis of covariance was used to compute mean differences between groups adjusting for baseline. Fisher's exact test was used to compare individual change in AHA raw scores with the smallest detectable difference (SDD) of 4 points. All participants receiving treatment finished the study. Improvement in AHA differed significantly between groups (p=0.007). No significant differences in the secondary outcome measures were found. Eight out of 10 participants in the rTMS/CIMT group showed improvement greater than the SDD, but only two out of nine in the sham rTMS/CIMT group showed such improvement (p=0.023). No serious adverse events occurred. Primed, low-frequency rTMS combined with CIMT appears to be safe, feasible, and efficacious in pediatric hemiparesis. Larger clinical trials are now indicated. © 2013 Mac Keith Press.

  6. Role of Brain-Derived Neurotrophic Factor in Beneficial Effects of Repetitive Transcranial Magnetic Stimulation for Upper Limb Hemiparesis after Stroke.

    PubMed

    Niimi, Masachika; Hashimoto, Kenji; Kakuda, Wataru; Miyano, Satoshi; Momosaki, Ryo; Ishima, Tamaki; Abo, Masahiro

    2016-01-01

    Repetitive transcranial magnetic stimulation (rTMS) can improve upper limb hemiparesis after stroke but the mechanism underlying its efficacy remains elusive. rTMS seems to alter brain-derived neurotrophic factor (BDNF) and such effect is influenced by BDNF gene polymorphism. To investigate the molecular effects of rTMS on serum levels of BDNF, its precursor proBDNF and matrix metalloproteinase-9 (MMP-9) in poststroke patients with upper limb hemiparesis. Poststroke patients with upper limb hemiparesis were studied. Sixty-two patients underwent rehabilitation plus rTMS combination therapy and 33 patients underwent rehabilitation monotherapy without rTMS for 14 days at our hospital. One Hz rTMS was applied over the motor representation of the first dorsal interosseous muscle on the non-lesional hemisphere. Fugl-Meyer Assessment and Wolf Motor Function (WMFT) were used to evaluate motor function on the affected upper limb before and after intervention. Blood samples were collected for analysis of BDNF polymorphism and measurement of BDNF, proBDNF and MMP-9 levels. Two-week combination therapy increased BDNF and MMP-9 serum levels, but not serum proBDNF. Serum BDNF and MMP-9 levels did not correlate with motor function improvement, though baseline serum proBDNF levels correlated negatively and significantly with improvement in WMFT (ρ = -0.422, p = 0.002). The outcome of rTMS therapy was not altered by BDNF gene polymorphism. The combination therapy of rehabilitation plus low-frequency rTMS seems to improve motor function in the affected limb, by activating BDNF processing. BDNF and its precursor proBDNF could be potentially suitable biomarkers for poststroke motor recovery.

  7. Role of Brain-Derived Neurotrophic Factor in Beneficial Effects of Repetitive Transcranial Magnetic Stimulation for Upper Limb Hemiparesis after Stroke

    PubMed Central

    Kakuda, Wataru; Miyano, Satoshi; Momosaki, Ryo; Abo, Masahiro

    2016-01-01

    Background Repetitive transcranial magnetic stimulation (rTMS) can improve upper limb hemiparesis after stroke but the mechanism underlying its efficacy remains elusive. rTMS seems to alter brain-derived neurotrophic factor (BDNF) and such effect is influenced by BDNF gene polymorphism. Objectives To investigate the molecular effects of rTMS on serum levels of BDNF, its precursor proBDNF and matrix metalloproteinase-9 (MMP-9) in poststroke patients with upper limb hemiparesis. Methods Poststroke patients with upper limb hemiparesis were studied. Sixty-two patients underwent rehabilitation plus rTMS combination therapy and 33 patients underwent rehabilitation monotherapy without rTMS for 14 days at our hospital. One Hz rTMS was applied over the motor representation of the first dorsal interosseous muscle on the non-lesional hemisphere. Fugl-Meyer Assessment and Wolf Motor Function (WMFT) were used to evaluate motor function on the affected upper limb before and after intervention. Blood samples were collected for analysis of BDNF polymorphism and measurement of BDNF, proBDNF and MMP-9 levels. Results Two-week combination therapy increased BDNF and MMP-9 serum levels, but not serum proBDNF. Serum BDNF and MMP-9 levels did not correlate with motor function improvement, though baseline serum proBDNF levels correlated negatively and significantly with improvement in WMFT (ρ = -0.422, p = 0.002). The outcome of rTMS therapy was not altered by BDNF gene polymorphism. Conclusions The combination therapy of rehabilitation plus low-frequency rTMS seems to improve motor function in the affected limb, by activating BDNF processing. BDNF and its precursor proBDNF could be potentially suitable biomarkers for poststroke motor recovery. PMID:27007747

  8. Resting State Dense Array Gamma Oscillatory Activity as a Response Marker for Cerebellar-Repetitive Transcranial Magnetic Stimulation (rTMS) in Schizophrenia.

    PubMed

    Tikka, Sai Krishna; Garg, Shobit; Sinha, Vinod Kumar; Nizamie, S Haque; Goyal, Nishant

    2015-12-01

    As cerebellum and its abnormalities have been implicated in the pathophysiology of schizophrenia, repetitive transcranial magnetic stimulation (rTMS) of this alternate site has been suggested as a novel target for treating patients with this disorder. As resting state gamma activity measures functional brain connectivity, it could be used as a specific treatment marker. To investigate the effect of cerebellar-rTMS on resting state gamma activity, while studying its efficacy in recent onset schizophrenia patients. This rater-blinded prospective study was completed by 11 schizophrenia patients. They received 10 sessions of high-frequency (theta patterned) rTMS to midline cerebellum over 2 weeks. Resting state EEG was recorded using high (192-channel) resolution EEG at baseline and post rTMS. Gamma spectral power was calculated using fast Fourier transformation, Hanning window averaged over 8 scalp segments corresponding 8 lobes. Clinical improvement rated on the Positive and Negative Syndrome Scale and depressive symptoms assessed using the Calgary Depression Scale for Schizophrenia were other outcome variables. Nonparametric statistics were used. Over the treatment course, significant reduction was seen on negative syndrome and depression scores. Gamma spectral power in left frontal and temporal segments reduced significantly. Spearman correlation analysis showed that percentage reduction in psychopathology scores had significant positive correlation with percentage reduction in gamma spectral power. Cerebellar-rTMS might be an effective adjunct to treat intricate and lingering negative and affective symptoms. Resting state gamma spectral power in frontal and temporal regions might be used as a biomarker for treatment response.

  9. Concordance Between BeamF3 and MRI-neuronavigated Target Sites for Repetitive Transcranial Magnetic Stimulation of the Left Dorsolateral Prefrontal Cortex

    PubMed Central

    Mir-Moghtadaei, Arsalan; Caballero, Ruth; Fried, Peter; Fox, Michael D.; Lee, Katherine; Giacobbe, Peter; Daskalakis, Zafiris J.; Blumberger, Daniel M.; Downar, Jonathan

    2016-01-01

    Background The dorsolateral prefrontal cortex (DLPFC) is a common target for repetitive transcranial magnetic stimulation (rTMS) in major depression, but the conventional “5 cm rule” misses DLPFC in > 1/3 cases. Another heuristic, BeamF3, locates the F3 EEG site from scalp measurements. MRI-guided neuronavigation is more onerous, but can target a specific DLPFC stereotaxic coordinate directly. The concordance between these two approaches has not previously been assessed. Objective To quantify the discrepancy in scalp site between BeamF3 versus MRI-guided neuronavigation for left DLPFC. Methods Using 100 pre-treatment MRIs from subjects undergoing left DLPFC-rTMS, we localized the scalp site at minimum Euclidean distance from a target MNI coordinate (X − 38 Y + 44 Z + 26) derived from our previous work. We performed nasion-inion, tragus–tragus, and head-circumference measurements on the same subjects’ MRIs, and applied the BeamF3 heuristic. We then compared the distance between BeamF3 and MRI-guided scalp sites. Results BeamF3-to-MRI-guided discrepancies were <0.65 cm in 50% of subjects, <0.99 cm in 75% of subjects, and <1.36 cm in 95% of subjects. The angle from midline to the scalp site did not differ significantly using MRI-guided versus BeamF3 methods. However, the length of the radial arc from vertex to target site was slightly but significantly longer (mean 0.35 cm) with MRI-guidance versus BeamF3. Conclusions The BeamF3 heuristic may provide a reasonable approximation to MRI-guided neuronavigation for locating left DLPFC in a majority of subjects. A minor optimization of the heuristic may yield additional concordance. PMID:26115776

  10. Cost-effectiveness of electroconvulsive therapy compared to repetitive transcranial magnetic stimulation for treatment-resistant severe depression: a decision model.

    PubMed

    Vallejo-Torres, L; Castilla, I; González, N; Hunter, R; Serrano-Pérez, P; Perestelo-Pérez, L

    2015-05-01

    Electroconvulsive therapy (ECT) is widely applied to treat severe depression resistant to standard treatment. Results from previous studies comparing the cost-effectiveness of this technique with treatment alternatives such as repetitive transcranial magnetic stimulation (rTMS) are conflicting. We conducted a cost-effectiveness analysis comparing ECT alone, rTMS alone and rTMS followed by ECT when rTMS fails under the perspective of the Spanish National Health Service. The analysis is based on a Markov model which simulates the costs and health outcomes of individuals treated under these alternatives over a 12-month period. Data to populate this model were extracted and synthesized from a series of randomized controlled trials and other studies that have compared these techniques on the patient group of interest. We measure effectiveness using quality-adjusted life years (QALYs) and characterize the uncertainty using probabilistic sensitivity analyses. ECT alone was found to be less costly and more effective than rTMS alone, while the strategy of providing rTMS followed by ECT when rTMS fails is the most expensive and effective option. The incremental cost per QALY gained of this latter strategy was found to be above the reference willingness-to-pay threshold used in these types of studies in Spain and other countries. The probability that ECT alone is the most cost-effective alternative was estimated to be around 70%. ECT is likely to be the most cost-effective option in the treatment of resistant severe depression for a willingness to pay of €30,000 per QALY.

  11. Efficacy of single versus three sessions of high rate repetitive transcranial magnetic stimulation in chronic migraine and tension-type headache.

    PubMed

    Kalita, Jayantee; Laskar, Sanghamitra; Bhoi, Sanjeev Kumar; Misra, Usha Kant

    2016-11-01

    We report the efficacy of three versus single session of 10 Hz repetitive transcranial magnetic stimulation (rTMS) in chronic migraine (CM) and chronic tension-type headache (CTTH). Ninety-eight patients with CM or CTTH were included and their headache frequency, severity, functional disability and number of abortive medications were noted. Fifty-two patients were randomly assigned to group I (three true sessions) and 46 to group II (one true and two sham rTMS sessions) treatment. 10 Hz rTMS comprising 600 pulses was delivered in 412.4 s on the left frontal cortex. Outcomes were noted at 1, 2 and 3 months. The primary outcome was 50 % reduction in headache frequency, and secondary outcomes were improvement in severity, functional disability, abortive drugs and side effects. The baseline headache characteristics were similar between the two groups. Follow up at different time points revealed significant improvement in headache frequency, severity, functional disability and number of abortive drugs compared to baseline in both group I and group II patients, although these parameters were not different between the two groups. In group I, 31 (79.4 %) had reduction of headache frequency and 29 (74.4 %) converted to episodic headache. In group II, these were 24 (64.8 %) and 22 (59.2 %), respectively. In chronic migraine, the severity of headache at 2 months reduced in group I compared to group II (62.5 vs 35.3 %; P = 0.01). Both single and three sessions of 10 Hz rTMS were found to be equally effective in CM and CTTH, and resulted in conversion of chronic to episodic headache in 67.1 % patients.

  12. Effectiveness and acceptability of accelerated repetitive transcranial magnetic stimulation (rTMS) for treatment-resistant major depressive disorder: an open label trial.

    PubMed

    McGirr, Alexander; Van den Eynde, Frederique; Tovar-Perdomo, Santiago; Fleck, Marcelo P A; Berlim, Marcelo T

    2015-03-01

    Major depressive disorder (MDD) is a significant cause of worldwide disability and treatment resistance is common. High-frequency repetitive transcranial magnetic stimulation (HF-rTMS) has emerged as a treatment for MDD, and while efficacious, the daily commitment for typical 4-6 weeks of treatment poses a significant challenge. We aimed to determine the effectiveness and acceptability of an accelerated rTMS protocol for MDD. In this naturalistic trial, 27 patients with moderate to severe chronic and treatment-resistant MDD were treated with twice-daily HF-rTMS (10 Hz) applied over the left dorsolateral prefrontal cortex for 2 consecutive weeks (60,000 pulses). The primary outcomes were rates of clinical remission and response (16-item Quick Inventory of Depressive Symptomatology post-treatment score ≤ 6, and ≥ 50% reduction, respectively). Secondary outcomes were self-reported anxious symptoms, depressive symptoms and quality of life, and dropout rates as a proxy for acceptability. Ten (37.0%) patients met criteria for clinical remission and 15 (55.6%) were classified as responders, with comparable outcomes for both moderate and severe MDD. Clinician-rated improvements in depressive symptoms were paralleled in self-reported depressive and anxious symptoms, as well as quality of life. No patient discontinued treatment. This study is limited by short treatment duration that might be lengthened with corresponding improvements in effectiveness, limited duration of follow-up, small sample size, and an open-label design requiring randomized controlled replication. An accelerated protocol involving twice-daily sessions of HF-rTMS over the left DLPFC for 2 weeks was effective in treatment-resistant MDD, and had excellent acceptability. Additional research is required to optimize accelerated rTMS treatment protocols and determine efficacy using sham-controlled trials. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Effect of combined low-frequency repetitive transcranial magnetic stimulation and virtual reality training on upper limb function in subacute stroke: a double-blind randomized controlled trail.

    PubMed

    Zheng, Chan-juan; Liao, Wei-jing; Xia, Wen-guang

    2015-04-01

    The effect of combined low-frequency repetitive transcranial magnetic stimulation (LF rTMS) and virtual reality (VR) training in patients after stroke was assessed. In a double-blind randomized controlled trial, 112 patients with hemiplegia after stroke were randomly divided into two groups: experimental and control. In experimental group, the patients received LF rTMS and VR training treatment, and those in control group received sham rTMS and VR training treatment. Participants in both groups received therapy of 6 days per week for 4 weeks. The primary endpoint including the upper limb motor function test of Fugl-meyer assessment (U-FMA) and wolf motor function test (WMFT), and the secondary endpoint including modified Barthel index (MBI) and 36-item Short Form Health Survey Questionnaire (SF-36) were assessed before and 4 weeks after treatment. Totally, 108 subjects completed the study (55 in experimental group and 53 in control group respectively). After 4-week treatment, the U-FMA scores [mean difference of 13.2, 95% confidence interval (CI) 3.6 to 22.7, P<0.01], WMFT scores (mean difference of 2.9, 95% CI 2.7 to 12.3, P<0.01), and MBI scores (mean difference 16.1, 95% CI 3.8 to 9.4, P<0.05) were significantly increased in the experimental group as compared with the control group. The results suggested the combined use of LF rTMS with VR training could effectively improve the upper limb function, the living activity, and the quality of life in patients with hemiplegia following subacute stroke, which may provide a better rehabilitation treatment for subacute stroke.

  14. Left prefrontal high-frequency repetitive transcranial magnetic stimulation for the treatment of schizophrenia with predominant negative symptoms: a sham-controlled, randomized multicenter trial.

    PubMed

    Wobrock, Thomas; Guse, Birgit; Cordes, Joachim; Wölwer, Wolfgang; Winterer, Georg; Gaebel, Wolfgang; Langguth, Berthold; Landgrebe, Michael; Eichhammer, Peter; Frank, Elmar; Hajak, Göran; Ohmann, Christian; Verde, Pablo E; Rietschel, Marcella; Ahmed, Raees; Honer, William G; Malchow, Berend; Schneider-Axmann, Thomas; Falkai, Peter; Hasan, Alkomiet

    2015-06-01

    Investigators are urgently searching for options to treat negative symptoms in schizophrenia because these symptoms are disabling and do not respond adequately to antipsychotic or psychosocial treatment. Meta-analyses based on small proof-of-principle trials suggest efficacy of repetitive transcranial magnetic stimulation (rTMS) for the treatment of negative symptoms and call for adequately powered multicenter trials. This study evaluated the efficacy of 10-Hz rTMS applied to the left dorsolateral prefrontal cortex for the treatment of predominant negative symptoms in schizophrenia. A multicenter randomized, sham-controlled, rater-blinded and patient-blinded trial was conducted from 2007-2011. Investigators randomly assigned 175 patients with schizophrenia with predominant negative symptoms and a high-degree of illness severity into two treatment groups. After a 2-week pretreatment phase, 76 patients were treated with 10-Hz rTMS applied 5 days per week for 3 weeks to the left dorsolateral prefrontal cortex (added to the ongoing treatment), and 81 patients were subjected to sham rTMS applied similarly. There was no statistically significant difference in improvement in negative symptoms between the two groups at day 21 (p = .53, effect size = .09) or subsequently through day 105. Also, symptoms of depression and cognitive function showed no differences in change between groups. There was a small, but statistically significant, improvement in positive symptoms in the active rTMS group (p = .047, effect size = .30), limited to day 21. Application of active 10-Hz rTMS to the left dorsolateral prefrontal cortex was well tolerated but was not superior compared with sham rTMS in improving negative symptoms; this is in contrast to findings from three meta-analyses. Copyright © 2015 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  15. Effects of high-frequency repetitive transcranial magnetic stimulation (rTMS) on spontaneously hypertensive rats, an animal model of attention-deficit/hyperactivity disorder.

    PubMed

    Kim, Jungyun; Park, Heamen; Yu, Seong-Lan; Jee, Sungju; Cheon, Keun-Ah; Song, Dong Ho; Kim, Seung Jun; Im, Woo-Young; Kang, Jaeku

    2016-10-01

    The current treatment of choice for attention deficit hyperactivity disorder (ADHD) is pharmacotherapy. A search for new treatment options is underway, however, as the wide application of drugs to the general population of patients with ADHD is limited by side effects and the variance of pharmacokinetic effects of the drugs in each patient. In the present study, we applied repetitive transcranial magnetic stimulation (rTMS), a non-invasive treatment used in a number of other psychiatric disorders, to spontaneously hypertensive rats (SHRs), an animal model of ADHD, in order to assess the efficacy of the treatment in modifying behavioural symptoms as well as levels of dopamine, noradrenaline, serotonin, and brain-derived neurotrophic factor (BDNF). A total of fifteen sessions of high-frequency rTMS treatment were administered. Behavioural symptoms were observed using open field, Y-maze, and elevated plus-maze tests. Upon completion of the experiments, rats were sacrificed, and the neurochemical changes in brain tissue were analysed using high performance liquid chromatography and Western blotting. The SHRs treated with rTMS tended to exhibit less locomotor activity in the open field test over the course of treatment, but there was no improvement in inattention as measured by the Y-maze test. Furthermore, BDNF concentration increased and noradrenaline concentration decreased in the prefrontal cortex of SHRs treated with rTMS. The results of the present preclinical study indicate that rTMS may constitute a new modality of treatment for patients with ADHD, through further evaluation of specific treatment parameters as well as safety and efficacy in humans are required.

  16. Repetitive transcranial magnetic stimulation (rTMS) for the treatment of depression in Parkinson disease: a meta-analysis of randomized controlled clinical trials.

    PubMed

    Xie, Cheng-Long; Chen, Jie; Wang, Xiao-Dan; Pan, Jia-Lin; Zhou, Yi; Lin, Shi-Yi; Xue, Xiao-Dong; Wang, Wen-Wen

    2015-10-01

    The objective of this meta-analysis was to ev