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OBJECTIVE: To evaluate the effectiveness of osteopathic manipulative treatment (OMT) associated with transcranial direct current stimulation (tDCS) in reducing pain, disability, and improving quality of life in participants with non-specific chronic low back pain. DESIGN: A randomised double-blind clinical trial. SETTING: Clinical outpatient unit. SUBJECTS: 72 participants with non-specific chronic low back pain were randomised into three groups: active tDCS + OMT (n = 24), sham tDCS + sham OMT (n = 24), and sham tDCS + OMT (n = 24). INTERVENTIONS: Evaluations were performed before, after the intervention, and one month post-intervention. tDCS consisted of ten 20-minute sessions over two weeks (five sessions per week). OMT was administered once per week, with two sessions conducted before the first and sixth tDCS sessions. MAIN MEASURES: Pain, disability, and quality of life were assessed at baseline, after two weeks, and at one month of follow-up. RESULTS: The visual analogue scale showed a significant decrease in all groups (p < 0.001). However, tDCS + OMT and sham tDCS + OMT demonstrated a clinically significant reduction compared to the sham combination (effect size n² = 0.315). Roland-Morris scores decreased across all groups without specific group effects. EuroQoL 5-Dimension 3-Level improvement was observed only in the tDCS + OMT and sham tDCS + OMT groups (significant difference between T2 and T0, p = 0.002). CONCLUSION: The combination of OMT and tDCS did not provide clinically significant improvement over OMT alone in participants with non-specific chronic low back pain.

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Background: Hypertension is a clinical condition that presents an enormous prevalence worldwide. Despite there being gold-standard treatments, several people frequently present sequelae and die. Transcranial direct current stimulation (tDCS) emerges as a cheap, easy-to-use, and portable intervention to modulate the central nervous system and control cardiovascular parameters. Objective: To evaluate the tDCS effects on the hemodynamic and autonomic parameters of hypertensive people. Methods: This systematic review included clinical trials published in databases that used tDCS as an intervention, isolated or associated, in hypertensive people to modulate the hemodynamic and autonomic parameters. We calculated the effect sizes, performed a meta-analysis, and evaluated the risk of bias in the studies. Three different researchers performed all the steps presented in the methods section. Results: Four studies suited the eligibility criteria of this review. Some studies showed that tDCS isolated after one session generated improvements in hemodynamic and autonomic parameters. Despite in meta-analysis, no statistical differences were detected between the groups, there was a tendency to reduce systolic (MD: -0.72 (CI: -1.54; 0.11; p = 0.06) and diastolic blood pressure (MD: -1.23; CI: -3.45; 0.99; p < 0.01), and root mean square of successive differences (MD: 0.73; CI: -0.30; 1.76; p < 0.01). There was no statistical difference after ten tDCS sessions. All the studies presented a low risk of bias. Conclusion: After one session, isolated tDCS might be able to modulate hypertensive people's hemodynamic and autonomic parameters. The anodic stimulation over the primary motor cortex shows signs of being the best target to generate a response.

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OBJECTIVE: To examine the effect of nutritional counseling therapy (NCT) combined with transcranial direct current stimulation (tDCS) on Binge Eating Disorder (BED) symptoms. METHODS: 40 women with BED were randomly (ratio of 2:2:2) allocated to one of the groups: active tDCS (a-tDCS), NCT, sham tDCS (s-tDCS) with NCT, and a-tDCS with NCT. Home-based tDCS was applied to the dorsolateral prefrontal cortex for 28 sessions. RESULTS: A mixed analysis of variance showed no main effect between groups or a time × group interaction. However, a significant main effect was found for time on the primary outcome: Binge Eating Scale (p = 0.001; eta2p= 0.325), which tended to decrease during treatment and follow-up. A significant main effect was found on the secondary outcome: short-interval intracortical inhibition (SICI) (p = 0.02; eta2p= 0.112), a measure of inhibitory function, which increased from baseline to the final period in the a-tDCS group, without significant differences between groups. CONCLUSIONS: These findings reveal that the combined therapy did not have a synergic effect on BED symptoms. Since this is a pilot study and this is a promising area, we provide data to plan future larger-scale studies investigating the effects of tDCS and behavioral interventions in BED treatment.

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BACKGROUND/OBJECTIVES: Fibromyalgia (FM) is a chronic condition characterized by widespread musculoskeletal pain, fatigue, and impaired motor performance. This study aimed to investigate the effects of transcranial direct current stimulation (tDCS) during virtual reality (VR) tasks on the motor performance of women with FM. METHODS: Participants were divided into two groups: Group A received active tDCS for 10 days followed by sham tDCS for 10 days, while Group B received the opposite sequence. Both groups performed VR tasks using MoveHero software (v. 2.4) during the tDCS sessions. Motor performance was assessed by the number of hits (movement with correct timing to reach the targets) and absolute (accuracy measure) and variable (precision measure) errors during VR tasks. Participants were 21 women, aged 30-50 years, and diagnosed with FM. RESULTS: Group A, which received active tDCS first, presented significant improvements in motor performance (number of hits and absolute and variable errors). The benefits of active tDCS persisted into the sham phase, suggesting a lasting neuroplastic effect. CONCLUSIONS: tDCS during VR tasks significantly improved motor performance in women with FM, particularly in complex, extensive movements. These findings indicate that tDCS enhances neuroplasticity, leading to sustained motor improvements, making it a promising therapeutic tool in FM rehabilitation.

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BACKGROUND: Stroke survivors often experience autonomic nervous system (ANS) dysfunction. While Transcranial Direct Current Stimulation (tDCS) has been shown to modulate the ANS when applied to the left hemisphere, its effects on the right hemisphere remain unexplored. OBJECTIVE: We aimed to compare the effects of tDCS applied to both the injured and the contralateral hemispheres on heart rate variability (HRV) and functional capacity in individuals post-stroke. METHODS: Twenty individuals with cerebral hemisphere lesions (ten with right-hemisphere lesions and ten with left-hemisphere lesions) were randomized into four groups: anodal and sham tDCS on the left temporal cortex (T3) and anodal and sham tDCS on the right temporal cortex (T4). HRV was assessed before the intervention, after the six-minute walk test (6MWT), and following tDCS. HRV data were categorized into frequency ranges: low frequency (LF), high frequency (HF), and sympathovagal balance. The 6MWT (meters) was conducted both pre- and post-tDCS. RESULTS: In individuals with right-hemisphere lesions, a higher global LF value was observed (right side: 71.4 ± 16.8 nu vs. left side: 65.7 ± 17.3 nu; p = 0.008), as well as lower values of the HF component (right side: 29.5 ± 18.9 nu vs. left side: 34.0 ± 17.4 nu; p = 0.047), consequently exhibiting higher global values of the low/high-frequency ratio (right side: 3.9 ± 2.8 vs. left side: 2.9 ± 2.4). Regarding the stimulation site, tDCS over T3 led to a lower overall value of the low/high-frequency ratio (left hemisphere: 3.0 ± 2.2 vs. right hemisphere: 3.7 ± 2.9; p = 0.040) regardless of the lesion location. A significant increase in the distance covered in the 6MWT was observed for individuals with lesions in both hemispheres after tDCS at T3. CONCLUSIONS: Participants with right-hemisphere lesions exhibited superior global sympathetic autonomic nervous system activity. When the tDCS was applied on the left hemisphere, it maintained lower sympathovagal balance values and improved functional capacity regardless of the hemisphere affected by the stroke.

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Introduction: Chronic stress is a condition characterized by prolonged stimulation, leading to mental and physical weakness. It can have detrimental effects on individuals' mental health and cognitive function, potentially causing various health issues. This article explores the potential of non-invasive neuromodulation techniques, specifically transcranial direct current stimulation (tDCS) and transcutaneous auricular vagus nerve stimulation (taVNS), in managing chronic stress and improving sleep quality. Methods: The study conducted a randomized, double-blinded, controlled trial with participants experiencing chronic stress. In total, 100 participants were randomly assigned to one of four conditions: the anodal tDCS group (n = 50), the sham tDCS group (n = 50), the taVNS group (n = 50), or the sham taVNS group (n = 50). Within each condition, participants received five sessions of either active treatment or sham treatment, with 20 min of tDCS over the dorsolateral prefrontal cortex (2 mA) for the tDCS groups, or taVNS on the left ear (20 Hz) for the taVNS groups. At baseline, post-intervention, and 4 weeks thereafter, we evaluated stress using the Lipp's Inventory of Stress Symptoms for Adults (LSSI), perceived stress through the Perceived Stress Scale (PSS-10), and sleep quality via the Pittsburgh Sleep Quality Index (PSQI). Results: The tDCS and taVNS interventions resulted in reduced stress levels, improved sleep quality, and enhanced perception of stress. Discussion: These findings suggest that tDCS and taVNS hold promise as effective treatments for chronic stress, offering a safe and accessible approach to improving individuals' wellbeing and overall quality of life. Clinical trial registration: https://ensaiosclinicos.gov.br/rg/RBR-2ww2ts8, identifier UTN: U1111-1296-1810; Brazilian Registry of Clinical Trials (REBEC) RBR-2ww2ts8.

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INTRODUCTION AND HYPOTHESIS: Transcranial direct current stimulation (tDCS) can enhance muscle function in healthy individuals. However, it is unknown if tDCS associated with pelvic floor muscle training (PFMT) can improve pelvic floor muscle function (PFMF) in healthy women. The aim of this study was to investigate the acute effect of a single session of tDCS in PFMF compared with sham-tDCS in healthy women. METHODS: A double-blind, cross-over, randomized clinical trial was conducted with healthy, nulliparous and sexually active women. PFMF was assessed by bidigital palpation (PERFECT scale) and intravaginal pressure by a manometer (Peritron™). Participants randomly underwent two tDCS sessions (active and sham) 7 days apart. The electrode was positioned equal for both protocols, the anode electrode in the supplementary motor area (M1) and the cathode electrode in the right supraorbital frontal cortex (Fp2). The current was applied for 20 min at 2 mA in active stimulation and for 30 s in sham-tDCS. The tDCS applications were associated with verbal instructions to PFMT in a seated position. After each tDCS session PFMF was reevaluated. RESULTS: Twenty young healthy women (aged 23.4 ± 1.7 years; body mass index 21.7 ± 2.2 kg/m2) were included. No difference was observed in power, endurance, and intravaginal pressure of PFMF (p > 0.05). The number of sustained contractions improved from 3.0 (2.0-3.5) to 4.0 (3.0-5.0) after active-tDCS (p = 0.0004) and was superior to sham-tDCS (p = 0.01). CONCLUSION: The number of sustained contractions of PFM improved immediately after a single active-tDCS session, with a difference compared with the post-intervention result of sham-tDCS in healthy young women.

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Parkinson's disease is the second most common neurodegenerative disease, but therapeutic options such as neuromodulation continue to show variable effects, making clinical management of the disease difficult. This systematic review with meta-analysis and meta-regression aimed to analyze the isolated effect of cortical modulation with transcranial direct current stimulation (tDCS) compared to sham stimulation on cognitive changes in people with Parkinson's disease. The databases used were: Web of Science, Scopus, PsycINFO, PubMed, and Cochrane. The results showed that tDCS can influence the improvement of cognition in PD (Inverse Variance:0.24 [95% Confidence Interval: 0.09 to -0.40], p < 0.00). The meta-analysis showed that active tDCS can influence cognitive function by improving aspects related to memory (Inverse Variance:0.34 [95% Confidence Interval: 0.07 to 0.61], p < 0.01) and reducing reaction time in cognitive tasks (Inverse Variance:0.42 [95% Confidence Interval: 0.07 to 0.76], p < 0.02). Innovative meta-regression analyses showed that variables such as age (Q = 2.54, df = 1, p < 0.11), education level (Q = 2.62, df = 1, p < 0.10), disease duration (Q = 0.01, df = 1, p < 0.92), and Unified PD Rating Scale stage (Q = 0.01, df = 1, p < 0.92) did not influence the results. Thus, tDCS may be a therapeutic option for cognitive changes in people with PD, and we suggest further studies to identify protocols that can be replicated.

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BACKGROUND: Runners seek health benefits and performance improvement. However, fatigue might be considered a limiting factor. Transcranial Direct Current Stimulation (tDCS) has been investigated to improve performance and reduce fatigue in athletes. While some studies showing that tDCS may improve a variety of physical measures, other studies failed to show any benefit. OBJECTIVE: To evaluate the acute effects of tDCS on central and peripheral fatigue compared to a sham intervention in recreational runners. METHODS: This is a triple-blind, controlled, crossover study of 30 recreational runners who were randomized to receive one of the two interventions, anodal or sham tDCS, after the fatigue protocol. The interventions were applied to the quadriceps muscle hotspot for 20 min. Peak torque, motor-evoked potential, and perceived exertion rate were assessed before and after the interventions, and blood lactate level was assessed before, during, and after the interventions. A generalized estimated equation was used to analyze the peak torque, motor-evoked potential, and blood lactate data, and the Wilcoxon test was used for perceived exertion rate data. RESULTS: Our findings showed no difference between anodal tDCS and sham tDCS on peak torque, motor-evoked potential, blood lactate, and perceived exertion rate. CONCLUSION: The tDCS protocol was not effective in improving performance and reducing fatigue compared to a sham control intervention. BRAZILIAN CLINICAL TRIALS REGISTRY: RBR-8zpnxz.

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Spinocerebellar ataxia (SCA) results in balance and coordination impairment, and current treatments have limited efficacy. Recent evidence suggests that combining postural training with cerebellar transcranial direct current stimulation (ctDCS) can improve these symptoms. However, the combined effects of ctDCS and postural training on individuals with spinocerebellar ataxia remain underexplored. Ten volunteers with (SCA type 3) participated in a triple-blind, randomized, crossover study to receive a single session of ctDCS (2 mA for 20 min) and a sham ctDCS session separated by at least one week. The Biodex Balance System was used to assess balance at each session, measuring overall stability index, anteroposterior stability index, and medial-lateral stability index. As secondary outcomes, cerebellar ataxia symptoms were evaluated using the 8-item Scale for Assessment and Rating of Ataxia. The assessments were conducted before and after each session. The results indicated that ctDCS enhanced the overall stability index when compared to sham ctDCS (Z = -2.10, p = 0.03), although it did not significantly affect the anteroposterior or medial-lateral stability indices. Compared to the baseline, a single session of ctDCS reduced appendicular symptoms related to cerebellar ataxia, as evidenced by improvements in the nose-finger test (Z = -2.07, p = 0.04), fast alternating hand movements (Z = -2.15, p = 0.03), and heel-to-shin slide (Z = -1.91, p = 0.05). In conclusion, our study suggests that a single session of ctDCS, in combination with postural training, can enhance balance and alleviate ataxia symptoms in individuals with cerebellar ataxia. This study was approved by the local research ethics committee (No. 2.877.813) and registered on clinicaltrials.org (NCT04039048 - https://www.clinicaltrials.gov/study/NCT04039048 ) on 2019-07-28.

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Background: Hypertension is a global issue that is projected to worsen with increasingly obese populations. The central nervous system including the parts of the cortex plays a key role in hemodynamic stability and homeostatic control of blood pressure (BP), making them critical components in understanding and investigating the neural control of BP. This study investigated the effects of anodal transcranial direct current stimulation (tDCS) associated with aerobic physical exercise on BP and heart rate variability in hypertensive patients. Methods: Twenty hypertensive patients were randomized into two groups: active tDCS associated with aerobic exercise or sham tDCS associated with aerobic exercise. BP and heart rate variability were analyzed before (baseline) and after twelve non-consecutive sessions. After each tDCS session (2 mA for 20 min), moderate-intensity aerobic exercise was carried out on a treadmill for 40 min. Results: A total of 20 patients were enrolled (53.9 ± 10.6 years, 30.1 ± 3.7 Kg/m2). There were no significant interactions between time and groups on diastolic BP during wake, sleep, over 24 and 3 h after the last intervention. Heart rate variability variables showed no significant difference for time, groups and interaction analysis, except for HF (ms2) between groups (p < 0.05). Conclusion: Anodal tDCS over the temporal cortex associated with aerobic exercise did not induce improvements in BP and heart rate variability. Clinical trial registration: https://ensaiosclinicos.gov.br/rg/RBR-56jg3n/1, identifier: RBR-56jg3n.

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OBJECTIVE: To investigate whether transcranial direct-current stimulation (tDCS) optimizes the performance of a wheelchair basketball player on precision tasks. METHODS: A right-handed wheelchair basketball player (1.5 points functional class) with myelomeningocele (low lumbar level) participated in this case study. The tDCS neuromodulation protocol was applied throughout 10 interventions of 20 minutes with a current intensity of 2 mA, simultaneously with sport-specific training, 3 times a week for 4 weeks. Anodic stimulation was performed on the right cerebellar hemisphere (CB2) and cathodic stimulation in the left dorsolateral prefrontal cortex. A control participant was submitted to a sham-tDCS stimulation protocol for the same period. Functional performance was assessed before the intervention and after the 5th and 10th interventions using "pass accuracy," "free-throw shooting," and "spot shot" tests. Outcome measures were compared using percentage differences between preintervention, intermediate intervention, and postintervention values. RESULTS: There was a gradual increase in the athlete's total and average scores in all tests performed, with an overall improvement of 78% between the baseline and final assessments, while the control participant had an overall improvement of 6.5%. CONCLUSION: The tDCS protocol was effective in improving performance in precision activities in a wheelchair basketball player.

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OBJECTIVE: To analyze the effects of transcranial direct current stimulation (tDCS) and transcranial magnetic stimulation (TMS) on the cognitive function of individuals with Alzheimer's disease (AD). METHODS: This systematic review with meta-analysis and meta-regression included randomized clinical trials published until 05/2022. We included studies conducted with individuals with AD of both sexes, aged between 55 and 85 years, treated with tDCS, TMS, or both. RESULTS: Twenty-one studies were included in the systematic review and sixteen in the meta-analysis. Meta-regression suggested a significant influence of anodic tDCS with current intensity of 1.5 mA on cognitive function. Significant results were found with treatment frequencies of three and five days a week for two weeks. Subgroup analysis found that anodic tDCS influences cognitive function, regardless of AD stage. Similar was observed for TMS using a frequency of 20 Hz and current intensity of 90% of the resting motor threshold. DISCUSSION: Anodal tDCS and 20 Hz TMS have demonstrated the ability to improve cognitive function in AD by modulating neural activity. These therapies are safe and well-tolerated, offering promise as adjuncts to available pharmacological treatments. Studies with greater methodological rigor and parameter standardization are warranted. Comprehensive investigations involving neuroimaging techniques may provide a better understanding of the interaction between induced electrical fields and the complex neural networks affected in AD, paving the way for more personalized and effective neurostimulation approaches.

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BACKGROUND: Children diagnosed with cerebral palsy (CP) often experience various limitations, particularly in gross motor function and activities of daily living. Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique that has been used to improve movement, gross motor function, and activities of daily living. OBJECTIVE: This study aims to evaluate the potential additional effects of physiotherapy combined with tDCS in children with CP in comparison with physiotherapy only. METHODS: This is a 2-arm randomized controlled trial that will compare the effects of tDCS as an adjunctive treatment during rehabilitation sessions to rehabilitation without tDCS. Children with CP classified by the Gross Motor Function Classification System as levels I and II will be randomly assigned to either the sham + rehabilitation group or the tDCS + rehabilitation group. The primary outcome will be the motor skills assessed using the Gross Motor Function Measure domain E scores, and the secondary outcome will be the measurement scores of the children's quality of life. The intervention will consist of a 10-day stimulation protocol with tDCS spread over 2 weeks, with stimulation or sham tDCS administered for 20 minutes at a frequency of 1 Hz, in combination with physiotherapy. Physical therapy exercises will be conducted in a circuit based on each child's baseline Gross Motor Function Measure results. The participants' changes will be evaluated and compared in both groups. Intervenient features will be tested. RESULTS: Data collection is ongoing and is expected to be completed by January 2025. A homogeneous sample and clear outcomes may be a highlight of this protocol, which may allow us to understand the potential use of tDCS and for whom it should or should not be used. CONCLUSIONS: A study with good evidence and clear outcomes in children with CP might open an avenue for the potential best use of neurostimulation. TRIAL REGISTRATION: Brazilian Registry of Clinical Trials RBR-104h4s4y; https://tinyurl.com/47r3x2e4. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/52922.

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Objective: We aimed to open a discussion about the integration of artificial intelligence (AI) in science and clinical practice, specifically with regard to the use of transcranial direct current stimulation (tDCS) as a technique for managing chronic pain. Main Points of Discussion: To analyze the responses generated by ChatGPT and the best literature about tDCS, we formulated three questions. The answers from ChatGPT, compared to the guidelines and Cochrane review, showed that AI can be a potential strategy to help clinicians and researchers. AI such as ChatGPT is revolutionizing the academic field and clinical practice. However, there is still an unmet scientific and clinical discussion about the insertion of AI to help researchers and clinicians in the neuromodulation area treat chronic pain. Conclusion: We need to know the limits of the use of AI. Even though ChatGPT might be helpful, it should be used with caution in the academic field and clinical practice.

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BACKGROUND: Multiple sclerosis (MS) is a chronic autoimmune disease that causes progressive functional impairment, mainly in walking tasks. Noninvasive brain stimulation (NIBS) could influence the motor function and improving gait ability of patients. OBJECTIVE: The aim was to analyze the effects of NIBS (transcranial direct current stimulation [tDCS] or transcranial magnetic stimulation [TMS] on functional locomotion in people with multiple sclerosis (PwMS). METHODS: A search was conducted for randomized controlled trials published up to November 2023 comparing the application of NIBS versus a sham or control group. The primary outcome were spatiotemporal gait parameters and functional mobility. Two review authors independently assessed the risk of bias in the included studies, and we used the Grading of Recommendations Assessment, Development, and Evaluation methodology to rate the certainty of the evidence for each outcome. A meta-analysis was performed by pooling the appropriate data using RevMan Web. RESULTS: A total of four clinical trials were included for metanalysis. We observed that there is no statistically significant difference in overall effect in gait speed (MD = 0.08; 95% CI: -0.08-0.24; p = 0.32), and cadence (MD = 0.22; 95% CI: -11.54-11.98; p = 0.97%) between groups. But there was a statistically significant difference in overall effect in stride length between groups (MD:0.19; 95% CI: 0.07-0.31; p = 0.002), mainly when the intervention performed by multiple sessions and associated with motor rehabilitation (MD = 0.29; 95% CI: 0.14-0.44; p = 0.0002). CONCLUSIONS: tDCS applied by multiple session and combined with motor rehabilitation (i.e., aerobic and/or resistance training) can improve stride length in PwMS.

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BACKGROUND: Pelvic floor muscle training (PFMT) is widely used for pelvic floor muscle (PFM) weakness in women; however, it has no prolonged effects. OBJECTIVE: To evaluate the effect of Transcranial Direct Current Stimulation (tDCS) associated with PFMT on PFM contraction, sexual function and quality of life (QoL) in healthy women. STUDY DESIGN: 32 nulliparous women, aged 22.7 ± 0.42 years, were randomized into two groups: G1 (active tDCS combined with PFMT) and G2 (sham tDCS combined with PFMT). The treatment was performed three times a week for 4 weeks, totaling 12 sessions. PFM function was assessed using the PERFECT scheme (P = power, E = endurance, R = repetitions, F = rapid contractions, ECT = each timed contraction) and the perineometer (cmH2O). Sexual function was assessed by The Female Sexual Function Index, and QoL by the SF-36 questionnaire. These assessments were performed before and after the 12nd treatment session and after 30-day follow-up. RESULTS: There was a significant increase (p = 0.037) in the power of G2 compared to G1; repetitions and fast contraction increased in the G1 group, and the resistance increased in both groups, however, without statistical difference between the groups. ECT increased in the G1 group (p = 0.0). CONCLUSION: Active tDCS combined with PFMT did not potentiate the effect of the PFMT to increase the PFM function, QoL, and sexual function in healthy women. However, adjunctive tDCS to PFMT improved the time of contractions, maintaining it during follow-up.

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INTRODUCTION: Despite promising results, the effects of transcranial direct current stimulation (tDCS) in the early stages of stroke and its impact on brain activity have been poorly studied. Therefore, this study aimed to investigate the effect of tDCS applied over the ipsilesional motor cortex on resting-state brain activity in the early subacute phase of stroke. METHODS: This is a pilot, randomized, double-blind, proof-of-concept study. The patients with stroke were randomly assigned into two groups: anodal tDCS (A-tDCS) or sham tDCS (S-tDCS). For A-tDCS, the anode was placed over the ipsilesional motor cortex, while the cathode was placed over the left or right supraorbital area (Fp2 for left stroke or Fp1 for right stroke). For the real stimulation, a constant current of 1.0 mA was delivered for 20 min and then ramped down linearly for 30 s, maintaining a resistance below 10 kΩ. For the sham stimulation, the stimulator was turned on, and the current intensity was gradually increased for 30 s, tapered off over 30 s, and maintained for 30 min without stimulation. Each stimulation was performed for three consecutive sessions with an interval of 1 h between them. The primary outcome was spectral electroencephalography (EEG) analysis based on the Power Spectral Density (PSD) determined by EEG records of areas F3, F4, C3, C4, P3, and P4. Brain Vision Analyzer software processed the signals, EEG power spectral density (PSD) was calculated before and after stimulation, and alpha, beta, delta, and theta power were analyzed. The secondary outcomes included hemodynamic variables based on the difference between baseline (D0) and post-intervention session (D1) values of systolic (SBP) and diastolic (DBP) blood pressure, heart rate (HR), respiratory rate (RR) and peripheral oxygen saturation (SPO2). Mann-Whitney test was used to compare position measurements of two independent samples; Fisher's exact test was used to compare two proportions; paired Wilcoxon signed-rank test was used to compare the median differences in the within-group comparison, and Spearman correlations matrix among spectral power analysis between EEG bands was performed to verify consistency of occurrence of oscillations. Statistical significance was set at P < 0.05. RESULTS: An increase in PSD in the alpha frequency in the P4 region was observed after the intervention in the A-tDCS group, as compared to the placebo group (before = 6.13; after = 10.45; p < 0.05). In the beta frequency, an increase in PSD was observed in P4 (before = 4.40; after = 6.79; p < 0.05) and C4 (before = 4.43; after = 6.94; p < 0.05) after intervention in the A-tDCS group. There was a reduction in PSD at delta frequency in C3 (before = 293.8; after = 58.6; p < 0.05) after intervention in the A-tDCS group. In addition, it was observed a strong relationship between alpha and theta power in the A-tDCS group before and after intervention. However, the sham group showed correlations between more power bands (alpha and theta, alpha and delta, and delta and theta) after intervention. There was no difference in hemodynamic variables between the intra- (before and after stimulation) and inter-groups (mean difference). CONCLUSION: Anodal tDCS over the ipsilesional motor cortex had significant effects on the brain electrical activity in the early subacute stroke phase, increasing alpha and beta wave activities in sensorimotor regions while reducing slow delta wave activity in motor regions. These findings highlight the potential of anodal tDCS as a therapeutic intervention in the early stroke phase.

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