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1.
J Headache Pain ; 21(1): 142, 2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33302882

RESUMO

BACKGROUND: Several neuromodulation methods exists for migraine treatment. The aim of the present study was to perform a systematic review and meta-analysis of randomized controlled trials (RCTs) focusing on migraine treatment using neurostimulation methods. METHODS: We searched Medline and Embase up to July 1, 2020 for RCTs reporting acute or preventive treatment of migraine with either non-invasive or invasive neurostimulation methods. Two researchers independently assessed the eligibility of the retrieved studies and extracted data. Outcomes for the quantitative synthesis were 2 h pain free for acute treatment and headache days per month for preventive treatment. We performed subgroup analyses by treatment (stimulation method and site of application). Estimates were pooled using random-effects meta-analysis. RESULTS: Thirty-eight articles were included in the qualitative analysis (7 acute, 31 preventive) and 34 in the quantitative evaluation (6 acute, 28 preventive). Remote electrical neuromodulation (REN) was effective for acute treatment. Data were insufficient to draw conclusions for any other techniques (single studies). Invasive occipital nerve stimulation (ONS) was effective for migraine prevention, with a large effect size but considerable heterogeneity, whereas supra-orbital transcutaneous electrical nerve stimulation (TENS), percutaneous electrical nerve stimulation (PENS), and high-frequency repetitive transcranial magnetic stimulation (rTMS) over the primary motor cortex (M1) were effective, with small to medium effect sizes. Vagus-nerve stimulation, left prefrontal cortex rTMS, and cathodal transcranial direct current stimulation (tDCS) over the M1 had no significant effect and heterogeneity was high. CONCLUSION: Several neuromodulation methods are of potential interest for migraine management, but the quality of the evidence is very poor. Future large and well-conducted studies are needed and could improve on the present results.


Assuntos
Transtornos de Enxaqueca , Estimulação Transcraniana por Corrente Contínua , Estimulação Elétrica Nervosa Transcutânea , Humanos , Transtornos de Enxaqueca/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Estimulação Magnética Transcraniana
2.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(5): 756-764, 2020 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-33140598

RESUMO

Repetitive transcranial magnetic stimulation(rTMS) is a painless and non-invasive method for stimulation and modulation in the field of cognitive neuroscience research and clinical neurological regulation. In this paper, adult Wistar rats were divided into the rTMS group and control group randomly. Rats in the rTMS group were stimulated with 5 Hz rTMS for 14 days, while the rats in the control group did not accept any stimulation. Then, the behavior and local field potentials (LFPs) were recorded synchronously when the rats perform a working memory (WM) task with T-maze. Finally, the time-frequency distribution and coherence characteristics of the LFPs signal in the prefrontal cortex (PFC) during working memory task were analyzed. The results showed that the rats in the rTMS group needed less training days to reach the task correction criterion than the control group (P < 0.05). Compared with the control group, the rTMS group has higher energy (P < 0.01) in θ band (4~12 Hz) and γ band (30~80 Hz). The coherence between the channel pairs decreases as the spatial distance of the channel pairs increases, and the rTMS group exhibits a higher coherence than the control group (P < 0.01). It is concluded that 5 Hz rTMS can improve the excitability of rat prefrontal cortical neurons to a certain extent, and has a positive effect on the working memory ability of normal rats. The results of this paper may provide important theoretical support for further research on the mechanism of action of rTMS on WM.


Assuntos
Memória de Curto Prazo , Estimulação Magnética Transcraniana , Animais , Neurônios , Córtex Pré-Frontal , Ratos , Ratos Wistar
3.
PLoS One ; 15(11): e0242056, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33226992

RESUMO

How and to what extent electrical brain activity reflects pharmacologically altered states and contents of consciousness, is not well understood. Therefore, we investigated whether measures of evoked and spontaneous electroencephalographic (EEG) signal diversity are altered by sub-anaesthetic levels of ketamine compared to normal wakefulness, and how these measures relate to subjective experience. High-density 62-channel EEG was used to record spontaneous brain activity and responses evoked by transcranial magnetic stimulation (TMS) in 10 healthy volunteers before and during administration of sub-anaesthetic doses of ketamine in an open-label within-subject design. Evoked signal diversity was assessed using the perturbational complexity index (PCI), calculated from EEG responses to TMS perturbations. Signal diversity of spontaneous EEG, with eyes open and eyes closed, was assessed by Lempel Ziv complexity (LZc), amplitude coalition entropy (ACE), and synchrony coalition entropy (SCE). Although no significant difference was found in TMS-evoked complexity (PCI) between the sub-anaesthetic ketamine condition and normal wakefulness, all measures of spontaneous EEG signal diversity (LZc, ACE, SCE) showed significantly increased values in the sub-anaesthetic ketamine condition. This increase in signal diversity correlated with subjective assessment of altered states of consciousness. Moreover, spontaneous signal diversity was significantly higher when participants had eyes open compared to eyes closed, both during normal wakefulness and during influence of sub-anaesthetic ketamine. The results suggest that PCI and spontaneous signal diversity may reflect distinct, complementary aspects of changes in brain properties related to altered states of consciousness: the brain's capacity for information integration, assessed by PCI, might be indicative of the brain's ability to sustain consciousness, while spontaneous complexity, as measured by EEG signal diversity, may be indicative of the complexity of conscious content. Thus, sub-anaesthetic ketamine may increase the complexity of the conscious content and the brain activity underlying it, while the level or general capacity for consciousness remains largely unaffected.


Assuntos
Encéfalo/fisiologia , Eletroencefalografia/efeitos dos fármacos , Alucinógenos/administração & dosagem , Ketamina/administração & dosagem , Adulto , Encéfalo/efeitos dos fármacos , Entropia , Potenciais Evocados/efeitos dos fármacos , Feminino , Alucinógenos/farmacologia , Voluntários Saudáveis , Humanos , Ketamina/farmacologia , Masculino , Estimulação Magnética Transcraniana/efeitos dos fármacos , Vigília/fisiologia , Adulto Jovem
4.
PLoS One ; 15(11): e0242941, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33253319

RESUMO

Word-production theories argue that during language production, a concept activates multiple lexical candidates in left temporal cortex, and the intended word is selected from this set. Evidence for theories on spoken-word production comes, for example, from the picture-word interference task, where participants name pictures superimposed by congruent (e.g., picture: rabbit, distractor "rabbit"), categorically related (e.g., distractor "sheep"), or unrelated (e.g., distractor "fork") words. Typically, whereas congruent distractors facilitate naming, related distractors slow down picture naming relative to unrelated distractors, resulting in semantic interference. However, the neural correlates of semantic interference are debated. Previous neuroimaging studies have shown that the left mid-to-posterior STG (pSTG) is involved in the interference associated with semantically related distractors. To probe the functional relevance of this area, we targeted the left pSTG with focal repetitive transcranial magnetic stimulation (rTMS) while subjects performed a picture-word interference task. Unexpectedly, pSTG stimulation did not affect the semantic interference effect but selectively increased the congruency effect (i.e., faster naming with congruent distractors). The facilitatory TMS effect selectively occurred in the more difficult list with an overall lower name agreement. Our study adds new evidence to the causal role of the left pSTG in the interaction between picture and distractor representations or processing streams, only partly supporting previous neuroimaging studies. Moreover, the observed unexpected condition-specific facilitatory rTMS effect argues for an interaction of the task- or stimulus-induced brain state with the modulatory TMS effect. These issues should be systematically addressed in future rTMS studies on language production.


Assuntos
Reconhecimento Visual de Modelos/fisiologia , Lobo Temporal/efeitos da radiação , Estimulação Magnética Transcraniana/métodos , Área de Wernicke/fisiologia , Adulto , Animais , Atenção/efeitos da radiação , Feminino , Humanos , Idioma , Reconhecimento Visual de Modelos/efeitos da radiação , Coelhos , Tempo de Reação/efeitos da radiação , Fala/efeitos da radiação , Área de Wernicke/efeitos da radiação
5.
PLoS Biol ; 18(11): e3000895, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33137084

RESUMO

A crucial aspect when learning a language is discovering the rules that govern how words are combined in order to convey meanings. Because rules are characterized by sequential co-occurrences between elements (e.g., "These cupcakes are unbelievable"), tracking the statistical relationships between these elements is fundamental. However, purely bottom-up statistical learning alone cannot fully account for the ability to create abstract rule representations that can be generalized, a paramount requirement of linguistic rules. Here, we provide evidence that, after the statistical relations between words have been extracted, the engagement of goal-directed attention is key to enable rule generalization. Incidental learning performance during a rule-learning task on an artificial language revealed a progressive shift from statistical learning to goal-directed attention. In addition, and consistent with the recruitment of attention, functional MRI (fMRI) analyses of late learning stages showed left parietal activity within a broad bilateral dorsal frontoparietal network. Critically, repetitive transcranial magnetic stimulation (rTMS) on participants' peak of activation within the left parietal cortex impaired their ability to generalize learned rules to a structurally analogous new language. No stimulation or rTMS on a nonrelevant brain region did not have the same interfering effect on generalization. Performance on an additional attentional task showed that this rTMS on the parietal site hindered participants' ability to integrate "what" (stimulus identity) and "when" (stimulus timing) information about an expected target. The present findings suggest that learning rules from speech is a two-stage process: following statistical learning, goal-directed attention-involving left parietal regions-integrates "what" and "when" stimulus information to facilitate rapid rule generalization.


Assuntos
Atenção/fisiologia , Aprendizagem/fisiologia , Lobo Parietal/fisiologia , Adulto , Encéfalo/fisiologia , Mapeamento Encefálico/métodos , Cognição/fisiologia , Feminino , Lobo Frontal/fisiologia , Lateralidade Funcional/fisiologia , Humanos , Idioma , Linguística/métodos , Imagem por Ressonância Magnética/métodos , Masculino , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Estimulação Magnética Transcraniana/métodos , Adulto Jovem
6.
Brain Nerve ; 72(11): 1239-1246, 2020 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-33191301

RESUMO

I describe quadripulse stimulation (QPS) briefly, and show several examples of its applications, such as rTMS treatment of Parkinson's disease, gait induction by lumbar rTMS, and roles of presupplementary motor area (pre-SMA) and SMA in visuo-motor sequence learning, role of SMA in negative compatibility effect, and role of dendritic back propagation potential in I-wave generation.


Assuntos
Córtex Motor , Doença de Parkinson , Humanos , Doença de Parkinson/terapia , Estimulação Magnética Transcraniana
7.
Brain Nerve ; 72(11): 1247-1253, 2020 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-33191302

RESUMO

To study cortical excitability changes induced by external stimulation with a certain rhythm, we developed a new method using motor evoked potentials (MEPs) elicited by transcranial magnetic stimulation (TMS) over the primary motor cortex. In this method, three conditioning TMS with the intensity below the motor threshold are given prior to the supra-threshold test stimulus with the four TMSs were separated by a certain interval (triad-conditioning stimulation: TCS). In healthy volunteers, MEP facilitation was elicited at an interval of 25ms, whereas TCSs with other intervals induced no facilitation. This frequency-dependent facilitation may reflect some intrinsic rhythm of M1 (25ms, i.e. 40Hz). In cortical myoclonus, the facilitation at 25ms was gone whereas facilitation was elicited by triad-conditioning stimulus at 40ms (25Hz), which is consistent with a previously reported abnormal beta rhythm in cortical myoclonus reported previously. Facilitation at 25ms was evoked in neither Parkinson's disease nor in amyotrophic lateral sclerosis. With TCS, we were able to investigate the intrinsic rhythmic activity of M1 and its changes in neurological disorders.


Assuntos
Esclerose Amiotrófica Lateral , Córtex Motor , Doença de Parkinson , Eletromiografia , Potencial Evocado Motor , Humanos , Estimulação Magnética Transcraniana
8.
Medicine (Baltimore) ; 99(42): e22611, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33080696

RESUMO

BACKGROUND: Central poststroke pain (CPSP) is a neuropathic pain syndrome that can occur after a cerebrovascular accident. It has negative effects on mood, sleep, rehabilitation, and quality of life in stroke patients. This systematic review assessed the efficacy and safety of nonpharmacological therapies for treating CPSP. METHODS: The Cochrane, PubMed, Embase, and Web of Science databases were systematically searched for studies from inception to August 2020. Two authors worked independently and in duplicate to identify suitable studies. RESULTS: Eleven studies were identified. Pain related to CPSP was ameliorated by precentral gyrus stimulation (P = .01), caloric vestibular stimulation (P = 0.004), transcranial direct current stimulation (P < .05), and bee venom acupuncture point injection (P = .009). Acupuncture (P = .72) and electroacupuncture therapies (P > .05) were as effective for thalamic pain as oral carbamazepine treatment. Motor cortex stimulation, but not deep brain stimulation (DBS), was effective for treating refractory CPSP, and appeared to be more effective than thalamic stimulation for controlling bulbar pain secondary to Wallenberg syndrome. However, DBS in the ventral striatum or anterior limb of the internal capsule improved depression (P = .020) and anxiety in patients with refractory CPSP. Some serious adverse events were reported in response to invasive electrical brain stimulation, but most of these effects recovered with treatment. CONCLUSIONS: Nonpharmacological therapies appear to be effective in CPSP, but the evidence is relatively weak. Invasive electrical brain stimulation can be accompanied by serious adverse events, but most patients recover from these effects.


Assuntos
Neuralgia/terapia , Acidente Vascular Cerebral/complicações , Terapia por Acupuntura , Terapia por Estimulação Elétrica , Humanos , Neuralgia/etiologia , Estimulação Magnética Transcraniana
9.
Sci Rep ; 10(1): 18520, 2020 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-33116195

RESUMO

Chronic diffuse body pain is unequivocally highly prevalent in Veterans who served in the 1990-91 Persian Gulf War and diagnosed with Gulf War Illness (GWI). Diminished motor cortical excitability, as a measurement of increased resting motor threshold (RMT) with transcranial magnetic stimulation (TMS), is known to be associated with chronic pain conditions. This study compared RMT in Veterans with GWI related diffuse body pain including headache, muscle and joint pain with their military counterparts without GWI related diffuse body pain. Single pulse TMS was administered over the left motor cortex, using anatomical scans of each subject to guide the TMS coil, starting at 25% of maximum stimulator output (MSO) and increasing in steps of 2% until a motor response with a 50 µV peak to peak amplitude, defined as the RMT, was evoked at the contralateral flexor pollicis brevis muscle. RMT was then analyzed using Repeated Measures Analysis of Variance (RM-ANOVA). Veterans with GWI related chronic headaches and body pain (N = 20, all males) had a significantly (P < 0.001) higher average RMT (% ± SD) of 77.2% ± 16.7% compared to age and gender matched military controls (N = 20, all males), whose average was 55.6% ± 8.8%. Veterans with GWI related diffuse body pain demonstrated a state of diminished corticomotor excitability, suggesting a maladaptive supraspinal pain modulatory state. The impact of this observed supraspinal functional impairment on other GWI related symptoms and the potential use of TMS in rectifying this abnormality and providing relief for pain and co-morbid symptoms requires further investigation.Trial registration: This study was registered on January 25, 2017, on ClinicalTrials.gov with the identifier: NCT03030794. Retrospectively registered. https://clinicaltrials.gov/ct2/show/NCT03030794 .


Assuntos
Dor Crônica/fisiopatologia , Córtex Motor/fisiopatologia , Síndrome do Golfo Pérsico/fisiopatologia , Adulto , Estudos de Casos e Controles , Guerra do Golfo , Humanos , Masculino , Militares , Córtex Motor/metabolismo , Manejo da Dor/métodos , Síndrome do Golfo Pérsico/complicações , Estimulação Magnética Transcraniana/métodos , Veteranos
10.
BMC Neurol ; 20(1): 365, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33023487

RESUMO

BACKGROUND: Transcranial magnetic stimulation (TMS) treatments have shown promise in improving arm recovery in stroke patients. Currently, little is known about patients' experiences with repetitive TMS treatment, and this lack of knowledge may affect optimal implementation in clinical practice. The aim of this explorative study was to gain insight in the perceived effects and experiences of the design and delivery of a rTMS treatment for upper limb recovery from the perspectives of stroke patients. METHODS: This qualitative study was conducted as part of a randomized controlled trial (RCT) in a specialized rehabilitation center. Data were collected through face-to-face semi-structured interviews with 13 stroke patients who completed a 10-day rTMS intervention for upper limb recovery. The interviews were recorded, transcribed verbatim and analyzed using thematic analysis. RESULTS: The major themes that emerged from the patients' feedback were the following: positive experiences of the treatment (experienced physical effects, comfort, therapeutic relationship, receiving information, learning about the brain, no burden of added rTMS treatment session, no unpleasant aspects), concerns (effects of stimulation of the brain, equipment, logistics), general experience of recovery, experienced psychological effects (grateful, sense of purpose, recovery as extra motivation to exercise, disappointment and hope of group allocation), and motivation to participate (personal benefit and cognitions, altruism). Important components related to the positive experience of the design and delivery of the treatment included comfort (i.e. moment of relaxation) and the sensation of a painless treatment without side-effects. Key concerns included uncertainty and anxiety about possible negative consequences and group allocation. CONCLUSIONS: This study demonstrates that rTMS is well accepted by stroke patients with an upper limb paresis. Besides the expectation of a therapeutic benefit, the patients reported various psychological effects. Positive experiences, such as the provision of a short moment of relaxation each day, could have practical implications for clinical stroke rehabilitation settings aimed at improving patient satisfaction. Explanation about and feedback from routine motor recovery progression monitoring at fixed times post-stroke is also valued by patients. Negative emotions may be limited or avoided by transparent and recurrent information delivery in future trials.


Assuntos
Satisfação do Paciente , Recuperação de Função Fisiológica , Reabilitação do Acidente Vascular Cerebral/métodos , Estimulação Magnética Transcraniana/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paresia/etiologia , Paresia/reabilitação , Acidente Vascular Cerebral/complicações , Extremidade Superior
11.
Sci Rep ; 10(1): 16108, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32999375

RESUMO

Transcranial direct current stimulation is applied to modulate activity, and excitability of the brain. Basically, LTP-like plasticity is induced when anodal tDCS (a-tDCS) is applied over the primary motor cortex. However, it has been shown that specific parameters of a-tDCS can induce a plasticity reversal. We aimed to systematically assess the intensity threshold for reversal of the direction of plasticity induced by a-tDCS, monitored by corticospinal excitability (CSE), and explored mechanisms regulating this reversal. Fifteen healthy participants received a-tDCS in pseudo-random order for 26 min with four intensities of 0.3, 0.7, 1, and 1.5 mA. To measure CSE changes, single-pulse TMS was applied over the left M1, and motor evoked potentials of a contralateral hand muscle were recorded prior to a-tDCS, immediately and 30-min post-intervention. Paired-pulse TMS was used to evaluate intracortical excitation and inhibition. CSE increased significantly following a-tDCS with an intensity of 0.7 mA; however, the expected effect decreased and even reversed at intensities of 1 and 1.5 mA. ICF was significantly increased while SICI and LICI decreased at 0.7 mA. On the other hand, a significant decrease of ICF, but SICI and LICI enhancement was observed at intensities of 1, and 1.5 mA. The present findings show an intensity threshold of ≥ 1 mA for 26 min a-tDCS to reverse LTP- into LTD-like plasticity. It is suggested that increasing stimulation intensity, with constant stimulation duration, activates counter-regulatory mechanisms to prevent excessive brain excitation. Therefore, stimulation intensity and plasticity induced by a-tDCS might non-linearly correlate in scenarios with prolonged stimulation duration.


Assuntos
Potencial Evocado Motor/fisiologia , Córtex Motor/fisiologia , Tratos Piramidais/fisiologia , Adulto , Eletrodos , Feminino , Humanos , Inibição Psicológica , Masculino , Músculo Esquelético/fisiologia , Inibição Neural/fisiologia , Plasticidade Neuronal/fisiologia , Estimulação Transcraniana por Corrente Contínua/métodos , Estimulação Magnética Transcraniana/métodos
12.
Nat Protoc ; 15(11): 3595-3614, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33005039

RESUMO

Transcranial magnetic stimulation (TMS) is a noninvasive method to stimulate the cerebral cortex that has applications in psychiatry, such as in the treatment of depression and anxiety. Although many TMS targeting methods that use figure-8 coils exist, many do not account for individual differences in anatomy or are not generalizable across target sites. This protocol combines functional magnetic resonance imaging (fMRI) and iterative electric-field (E-field) modeling in a generalized approach to subject-specific TMS targeting that is capable of optimizing the stimulation site and TMS coil orientation. To apply this protocol, the user should (i) operationally define a region of interest (ROI), (ii) generate the head model from the structural MRI data, (iii) preprocess the functional MRI data, (iv) identify the single-subject stimulation site within the ROI, and (iv) conduct E-field modeling to identify the optimal coil orientation. In comparison with standard targeting methods, this approach demonstrates (i) reduced variability in the stimulation site across subjects, (ii) reduced scalp-to-cortical-target distance, and (iii) reduced variability in optimal coil orientation. Execution of this protocol requires intermediate-level skills in structural and functional MRI processing. This protocol takes ~24 h to complete and demonstrates how constrained fMRI targeting combined with iterative E-field modeling can be used as a general method to optimize both the TMS coil site and its orientation.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Imagem por Ressonância Magnética/métodos , Estimulação Magnética Transcraniana/métodos , Encéfalo/diagnóstico por imagem , Humanos , Fluxo de Trabalho
13.
Artigo em Russo | MEDLINE | ID: mdl-33054007

RESUMO

PROBLEM RELEVANCE: As you know, complete successful recovery in stroke patients occurs only in 8% of cases, 20% need constant care. The use of innovative rehabilitation technologies, namely «thresholdless¼ low-frequency transcranial magnetic stimulation, will speed up the process of restoring impaired functions, increase independence in everyday life and, accordingly, the quality of life. AIM OF STUDY: To evaluate the effectiveness of use of low-frequency «thresholdless¼ transcranial magnetic stimulation in the treatment of patients in acute period of ischemic stroke. MATERIALS AND METHODS: The study included 93 patients aged from 49 to 68 years on second-third days of ischemic stroke. The 1st (main) group (n=48) received low-frequency «thresholdless¼ transcranial magnetic stimulation from the «Diamag¼ apparatus (AlMag-03) daily for 20 minutes, course - 8-10 procedures, with the background of drug treatment, and in addition to classes with an exercise therapy instructor and an occupational therapist. In the 2nd (control) group (n=45), standard therapy was carried out in accordance with the Procedure for rendering medical care to patients with stroke, only with the exception of physiotherapy. Assessment methods: clinical and neurological examination, indicators of duplex scanning of brachiocephalic vessels, Rivermead mobility index, modified Rankin scale, FIM scale (Functional Independence Measure), Hospital anxiety and depression scale (HADS). RESULTS AND DISCUSSION: In patients of the 1st (main) group, an increase in the linear velocity of blood flow in the internal carotid artery on the side of lesion was revealed by 18.1% when compared with the 2nd (control) group (p=0.042); mobility increased by 42.1%, functional independence in everyday life - by 38.1%, muscle strength - by 50%, compared with the 2nd (control) group (p=0.0005). According to the HADS scale, in 29 (60.8%) patients of the main group, psychoemotional disorders were not detected, neither a single case of significantly expressed symptoms of depression (p<0.0001). CONCLUSION: The inclusion of low-frequency transcranial electromagnetic stimulation in complex rehabilitation leads to the regression of movement disorders, reduces the level of anxiety and depression, improves daily activity and, as a consequence, the quality of life.


Assuntos
Isquemia Encefálica , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Idoso , Isquemia Encefálica/terapia , Humanos , Pessoa de Meia-Idade , Qualidade de Vida , Acidente Vascular Cerebral/terapia , Estimulação Magnética Transcraniana , Resultado do Tratamento
14.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3537-3543, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018767

RESUMO

In this study, we present a temporal interference (TI) concept to achieve focal and steerable stimulation in the targeted brain area through transcranial magnetic stimulation (TMS). This method works by inducing two high-frequency electric fields with a slight frequency difference via two independent coils. The intrinsic nonlinear nature of the nerve membrane, which acts as a low-pass filter, does not allow the nerve to engage at high frequencies. Instead, neurons at the intersection of two electric fields can follow the frequency difference of the two fields. For 3D MRI-derived head models, the finite element method is used to compute the electric field induced by the time-varying magnetic field along with the electric field penetration depth and the activated volume for the specific coil parameters. A deeper stimulation with an acceptable spatial spread can be obtained by controlling the intersection of the fields by finding the optimal position and orientation of the two coils. Moreover, by changing the voltage ratio of the coils, and not their mechanical orientation, the intended area can be dynamically driven. The computational results show that the TI technique is an efficient approach to resolve the electric field depth-focality trade-off, which can be a reasonable alternative to complex coil designs. The system proposed in this paper shows a great promise for a more dynamic and focused magnetic stimulation.


Assuntos
Encéfalo , Estimulação Magnética Transcraniana , Eletricidade , Campos Eletromagnéticos , Campos Magnéticos
15.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3549-3552, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018769

RESUMO

Repetitive Transcranial magnetic stimulation (rTMS) is a noninvasive brain stimulation technique that can influence cortical excitability. Low-frequency rTMS (stimulation frequency ≤1Hz) induces long-lasting inhibitory effects on cortical excitability. At the same time, EEG microstates have been studied and have been thought to corresponding to functional relevant brain-states. In order to investigate dynamic changes in EEG microstates after low-frequency rTMS, 20 healthy subjects received 1-Hz rTMS over the right motor area, and electroencephalography (EEG) in resting condition with eyes open was recorded before rTMS (Pre) and at 0 min, 20 min, 40 min, and 60 min after rTMS (Post0, Post20, Post40, and Post60). Resting state EEG data of all five sessions were computed using a clustering algorithm. Four EEG microstates were found and labeled with the letters A, B, C and D. No significant difference in duration was found among five sessions for four microstates. For microstates A, and B, there is an increase in the mean duration immediately after rTMS. And for microstate C, the mean duration at Post0 and Post60 was significantly higher than that before rTMS. For microstate D, there is an increase in the mean duration at 60min after rTMS. These results showed that we reproduced the same four microstate maps best representing the resting state EEG as found by others and that low-frequency rTMS produced long-lasting alterations in the mean duration of EEG microstates. It implies that low-frequency rTMS increases the stability of EEG microstates.


Assuntos
Excitabilidade Cortical , Córtex Motor , Encéfalo , Eletroencefalografia , Estimulação Magnética Transcraniana
16.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3852-3855, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018841

RESUMO

This paper describes the design and testing of a compact, battery-powered repetitive Transcranial Magnetic Stimulation (rTMS) prototype. This device generates a 10 Hz magnetic pulse train with peak flux density of 100 mT at 2 cm distance. Circuit component design, including the inductor, switched LC resonator, and boost converter, are discussed in the context of weight and size reduction, and performance optimization. The experimental approach and rationale together with acquired results validating the rTMS prototype design are presented. To the best of our knowledge, this is the first comprehensive feasibility demonstration of an inexpensive, lightweight, and portable rTMS device able to generate therapeutic levels of current, pulse rise time, and number of pulses. The generated magnetic field was kept to 0.1 Tesla for safety and testing considerations, but nevertheless was very close to therapeutic intensity, with driving circuitry scalable to support much stronger fields.Clinical Relevance- This feasibility study of a compact, battery-powered rTMS prototype test platform aims to enable broader and more convenient rTMS treatment at home, in a small clinic, vessel, or field hospital, and potentially, on an ambulatory basis.


Assuntos
Fontes de Energia Elétrica , Estimulação Magnética Transcraniana , Frequência Cardíaca , Campos Magnéticos
17.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 5326-5329, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33019186

RESUMO

We interface the head modelling, coil models, Graphical User Interface (GUI), and post-processing capabilities of the SimNIBS package with the boundary element fast multipole method (BEM-FMM), implemented in a MATLAB-based module. The resulting pipeline combines the best of both worlds: the individualized head modelling and ease-of-use of SimNIBS with the numerical accuracy of BEM-FMM. The corresponding TMS (transcranial magnetic stimulation) modeling package is developed and made available online. It imports a SimNIBS surface segmentation and a coil field, and then exports electric-field values in selected surfaces or volumes. Additional information is also made available, such as discontinuous compartment surface electric fields and associated surface electric charge distributions.


Assuntos
Cabeça , Estimulação Magnética Transcraniana
18.
J Clin Neurosci ; 79: 259-265, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33070908

RESUMO

Navigated transcranial magnetic stimulation (nTMS) is increasingly applied in language mapping. However, the application mode and task selection of nTMS are not standardized. The aim of this study was to assessed the necessity and validity of multitask nTMS language mapping by comparing results with extraoperative electrical cortical stimulation (eoECS). In this study, sixteen epilepsy surgery patients were examined by nTMS and eoECS language mapping, and the two results were compared. The mapping results were validated with pre- to postoperative language assessments. Compared with eoECS, nTMS showed the overall sensitivity of 82.4%, specificity of 95.1%, positive predictive value of 66.7%, and negative predictive value of 97.8%. Spontaneous speech was the most sensitive task in the frontal area, naming was the sensitive task in both frontal and temporal areas. The false responses were mainly located in the perisylvian region. Multitask nTMS helps to reduce missing language relevant cortex preoperatively. Selecting spontaneous speech and naming tasks in frontal area, comprehension and naming tasks in temporal and posterior language area would strike the balance between the validity and efficiency of the mapping procedure. These results manifested the necessity of applying multitask in nTMS language mapping. Our study highlighted the importance of the nTMS evaluation mode and task selection for epilepsy patients.


Assuntos
Mapeamento Encefálico/métodos , Estimulação Encefálica Profunda/métodos , Epilepsia/cirurgia , Neuronavegação/métodos , Percepção da Fala , Estimulação Magnética Transcraniana/métodos , Adulto , Encéfalo/cirurgia , Feminino , Humanos , Idioma , Masculino , Pessoa de Meia-Idade , Período Pré-Operatório
19.
Fisioterapia (Madr., Ed. impr.) ; 42(5): 267-276, sept.-oct. 2020. graf, tab
Artigo em Espanhol | IBECS | ID: ibc-195143

RESUMO

OBJETIVO: Realizar una revisión sistemática actualizada y crítica sobre los estudios clínicos que han utilizado la combinación de estimulación magnética transcraneal repetitiva (EMTr) con fisioterapia en pacientes con secuelas de enfermedad vascular cerebral (EVC) para conocer si existen efectos sinérgicos de ambas terapias sobre la función motora. ESTRATEGIA DE BÚSQUEDA Y SELECCIÓN DE ESTUDIOS: Revisión sistemática de estudios clínicos con grupo control. La búsqueda se realizó en las siguientes bases de datos: PubMed, MedLine, DynaMed, EBSCO, Science Direct y Latindex, de 2009 a 2019. Se encontró un total de 184 artículos, y basado en los criterios de inclusión se seleccionó un total de 10 estudios que combinaron fisioterapia con EMTr. SÍNTESIS DE RESULTADOS: Existen pocos estudios en donde se haya combinado la aplicación de EMTr con fisioterapia para la recuperación motora en EVC. Se encontraron diversos puntos de variabilidad en el diseño de los estudios, lo cual dificulta su comparación: número de participantes, tipo de fisioterapia aplicada, parámetros de estimulación, variables de desenlace, etc. Seis estudios demostraron efectos sinérgicos de la EMT + fisioterapia en la función motora en EVC. CONCLUSIONES: Se observaron múltiples puntos de variabilidad metodológica que pueden afectar la comparación entre los estudios. La evidencia disponible parece sugerir un efecto sinérgico de la combinación de EMTr + fisioterapia en la función motora en EVC


OBJECTIVE: To perform an updated and critical systematic review of the clinical studies that have used the combination of repetitive Transcranial Magnetic Stimulation (rTMS) and physiotherapy in patients with sequelae of stroke to establish whether there are synergistic effects of both therapies on motor function SEARCH STRATEGY AND STUDY SELECTION: Systematic review of clinical studies with control group. The search was carried out in the following databases: PubMed, MedLine, DynaMed, EBSCO, Science Direct and Latindex from 2009 to 2019. A total of 184 articles were found and, based on the inclusion criteria, a total of 10 studies were selected who combined physiotherapy with rTMS. SYNTHESIS OF RESULTS: There are few studies where rTMS has been combined with physiotherapy for motor recovery in stroke. Several points of variability were found in the design of the studies, which makes comparison difficult: number of participants, type of physiotherapy applied, stimulation parameters, outcome variables, etc. Six studies showed a synergistic effect of rTMS + physiotherapy on motor function in stroke. CONCLUSIONS: There are several points of methodological variability between studies but the available evidence suggests a possible synergistic effect of rTMS+physiotherapy


Assuntos
Humanos , Transtornos Cerebrovasculares/reabilitação , Transtornos Cerebrovasculares/terapia , Estimulação Magnética Transcraniana/instrumentação , Modalidades de Fisioterapia , Estimulação Magnética Transcraniana/métodos , Plasticidade Neuronal/fisiologia
20.
Medicine (Baltimore) ; 99(38): e22207, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32957353

RESUMO

BACKGROUND: Stroke is the primary cause of adult disability in China, which causes serious personal, family, and social burden. "Central peripheral central" closed-loop rehabilitation theory is proved to be an effective neural rehabilitation model. Based on this theory, repetitive transcranial magnetic stimulation (rTMS) combined with magnetic stimulation of Neiguan (PC6) and Sanyinjiao (SP6) may be an effective treatment for limb dysfunction after stroke. However, the efficacy and mechanism of repetitive magnetic stimulation of M1 region combined with magnetic stimulation of Neiguan and Sanyinjiao points on limb dysfunction after stroke has not been confirmed. METHODS/DESIGN: This study is a prospective, randomized, controlled, open trial. We randomly divided 42 subjects, aged 35 to 80 years, diagnosed with ischemic stroke within 1 month, into 2 groups with a ratio of 1:1. On the basis of this medical treatment, patients in the experimental group received 1 Hz rTMS in M1 area on the contralateral side, and 3 Hz rTMS treatment at Neiguan point and Sanyinjiao point on the affected side. The control group was treated with acupuncture (body acupuncture). All patients were treated once a day and followed up for 10 days. The National Institute of Health Stroke Scale score, simplified fulg Meyer, modified Barthel index, and cortical excitability were evaluated on the day of enrollment and the 10th day of treatment respectively. The modified Barthe index was followed up on the 30th day of treatment, and the adverse reactions were recorded at any time. The mechanism of rTMS will be revealed by Barthe index before treatment, on the 10th day of treatment and on the 30th day of follow-up. The results were analyzed by spss19.0 software, and the quantitative indexes were analyzed by t test and rank sum test. χ test was used for non-grade counting, and rank sum test was used for grade counting. All statistical tests were performed with bilateral test. If P value is less than or equal to .05, the difference will be considered statistically significant. CONCLUSION: The purpose of this study was to determine the effect of repetitive magnetic stimulation of M1 region combined with magnetic stimulation of Neiguan and Sanyinjiao points on limb function after stroke. Through this study, we expect to explore a new scheme for the treatment of poststroke dyskinesia, and prove that compared with rTMS and acupuncture alone, the closed-loop rehabilitation theory based on "center peripheral center" can be more efficient and safe in the treatment of poststroke limb dysfunction. TRIAL REGISTRATION: The trial was registered in China clinical trial registry (http://www.chictr.org.cn/index.aspx), ID: ChiCTR1900026890 (October 25, 2019).


Assuntos
Pontos de Acupuntura , Terapia por Acupuntura , Discinesias/terapia , Reabilitação do Acidente Vascular Cerebral/métodos , Estimulação Magnética Transcraniana , Discinesias/etiologia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Acidente Vascular Cerebral/complicações
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