Search

Background: The impact of noninvasive brain stimulation (NIBS) on cognitive and mental outcomes in Alzheimer's disease (AD) and mild cognitive impairment (MCI) remains under debate due to contradictory findings from systematic reviews and meta-analyses (SRMAs). To synthesize evidence from SRMAs assessing the effectiveness of NIBS techniques on cognitive and mental outcomes in AD and MCI populations. By comparing our findings to recent reviews and clinical guidelines, we highlight how this study addresses current limitations in the literature, provides a more holistic perspective on NIBS interventions, and guides future research and clinical practice. Methods: We searched four databases from inception to May 15, 2024, reviewing SRMAs that analyzed the effects of NIBS. Effect sizes, 95% confidence intervals (CIs), and prediction intervals were computed for each meta-analysis. The methodological quality of the SRMAs was evaluated using the Measurement Tool to Assess Systematic Reviews 2, and the quality of evidence was assessed through the Grading of Recommendations, Assessment, Development, and Evaluation criteria. Findings: Ten SRMAs detailing 22 associations were analyzed, focusing on two NIBS techniques across 12 unique outcomes. Significant improvements were observed in global cognition, language, executive function, and memory. Repetitive transcranial magnetic stimulation (rTMS) significantly enhanced short-term global cognition (standardized mean difference [SMD], 0.44; 95% CI 0.02–0.86), language (SMD, 1.64; 95% CI 1.22–2.06), executive function (SMD, 1.64; 95% CI 0.18–0.83), and long-term global cognition (SMD, 0.29; 95% CI 0.07–0.50). Transcranial direct current stimulation (tDCS) was effective in improving memory (SMD, 0.60; 95% CI 0.32–0.89) and executive function (SMD, 0.39; 95% CI 0.08–0.71). NIBS interventions showed no significant correlation with neuropsychiatric symptoms but demonstrated good tolerability in terms of safety and acceptability. Interpretation: This umbrella review indicates that NIBS techniques, particularly rTMS and tDCS, can significantly improve cognitive functions such as global cognition, language, executive functions, and memory in patients with AD and MCI. Despite potential benefits, results should be interpreted cautiously due to study heterogeneity and methodological limitations. Future studies should investigate their long-term effects and applicability across dementia types. [ABSTRACT FROM AUTHOR]

Background: Cognitive deficits are common nonmotor symptoms in Parkinson's disease (PD). Non-Invasive Brain Stimulation (NIBS) could be a potential aid to prevent or delay dementia progression in this clinical population. However, previous studies reported controversial results concerning their efficacy on cognitive symptoms of PD. Hence, the present meta-analysis aims to systematically examine the effects of NIBS as possible treatments for PD cognitive impairments. Understanding NIBS' impact on these symptoms may be of outstanding importance to implement new therapeutic strategies and improve the patients' quality of life. Methods: EMBASE, Scopus, and PubMed databases were systematically searched for consecutive studies published from 2000 to March 2023 describing Randomized Controlled Trials studies evaluating the effect of NIBS on PD cognitive symptoms. From the included studies, data concerning neuropsychological tests were extracted and grouped into six cognitive domains, separately analyzed. Hedge's method was computed as the effect size measure of the extracted data; heterogeneity among studies and publication bias were also assessed. The Cochrane's RoB2 tool was used to evaluate the risk of bias for each of the included studies. Results: After database searching and screening of texts, sixteen studies met the inclusion criteria. No significant results emerged from any investigated cognitive domain when comparing NIBS and sham treatments. Conclusion: Several factors may have contributed to the lack of effects; among these, methodological choices, the small sample of studies, the high heterogeneity of data and stimulation protocols pose the need for more controlled studies to highlight the potentiality of NIBS as a future treatment for PD cognitive impairments. [ABSTRACT FROM AUTHOR]

Over the last four decades, non-invasive brain stimulation techniques (NIBS) have significantly gained interest in the fields of cognitive sciences and dementia care, including neurorehabilitation, for its emerging potential in increasing the insights over brain functions and in boosting residual cognitive functions. In the present paper, basic physiological and technical mechanisms and different applications of NIBS were reviewed and discussed to highlight the importance of NIBS in multidisciplinary and translational approaches in clinical and research settings of cognitive sciences and neurodegenerative diseases, especially in Alzheimer's disease. Indeed, NIBS strategies may represent a promising opportunity to increase the potential of neuromodulation as efficacious interventions for individualized patients care. [ABSTRACT FROM AUTHOR]

Non-invasive brain stimulation (NIBS) and physical exercise (PE) intervention are currently the main and promising non-pharmacologic therapies for Alzheimer's Disease (AD) or Mild cognitive impairment (MCI), but it is not clear which one is the most effective. Therefore, the aim was to compare the effectiveness of NIBS and PE interventions on cognitive function in MCI/AD, which can further elucidate their advantages and disadvantages in cognitive efficacy and facilitate the optimization of treatment strategies based on the specific cognitive status of patients. Randomized controlled trials (RCTs) were searched from online databases until December 2023. Standardized Mean Changes pre- and post-treatment were calculated for cognitive outcomes measures. 79 RCTs met the inclusion criteria. For the global cognitive scale, PE significantly affected AD and MCI. Both NIBS and PE had a sustained and significant impact on AD/MCI based on the follow-up. In sub-category functions, NIBS had a significant effect on memory for both AD and MCI. However, PE only had a significant effect on AD, not on MCI. For executive function, only NIBS had a significant effect on AD. For language, NIBS and PE both had a significant impact only on AD. For attention, the only significant effect was NIBS on AD. NIBS significantly affects more cognitive domains of AD than PE, and significantly improves the memory function of MCI. Given the current evidence, NIBS appears to be a more promising intervention approach for delaying cognitive decline in patients with MCI or AD compared to PE. Highlights: • The current study is the first meta-analysis to compare the comparative efficacy of NIBS and PE interventions on various cognitive domains, for MCI or AD patients. • NIBS intervention has clear positive effect on various cognitive domains for patients with AD, and significant effect on the memory function for MCI. • NIBS is promising to be a better intervention approach to delay cognitive decline in MCI and AD than PE. [ABSTRACT FROM AUTHOR]

Background/Objectives: Multiple sclerosis (MS) is the most prevalent incurable nontraumatic neurological disability in young individuals. It causes numerous symptoms, including tingling, fatigue, muscle spasms, cognitive deficits, and neuropsychiatric disorders. This disease significantly worsens quality of life (QoL), and this dimension of general functioning provides valuable information about the effectiveness of treatment and well-being. There are psychological interventions that can improve QoL, but their number is limited. Therefore, searching for new methods that are as effective and safe as possible is ongoing. Methods: This review examines the potential effectiveness of transcranial direct current stimulation (tDCS) in improving the quality of life in patients with MS. Searches were conducted in the PubMed/Medline, Research Gate, and Cochrane databases. Results: The search yielded seven studies in which QoL was a primary or secondary outcome. Stimulation protocols displayed heterogeneity, especially concerning the choice of the stimulation site. Four studies demonstrated the effectiveness of tDCS in improving QoL, all of which (two) used anodal stimulation of the left DLPFC. Stimulation of the motor cortex has produced mixed results. The potential mechanisms of action of tDCS in improving QoL in MS are explained. These include improved synaptic plasticity, increased cerebral blood flow, salience network engagement through tDCS, and reduction of beta-amyloid deposition. The limitations are also detailed, and recommendations for future research are made. Conclusions: While the evidence is limited, tDCS has shown potential to improve QoL in MS patients in some studies. Prefrontal stimulation appears promising, and further research is recommended to explore this approach. [ABSTRACT FROM AUTHOR]

Background: Postoperative delirium (POD) is the most common neurological adverse event among elderly patients undergoing surgery. POD is associated with an increased risk for postoperative complications, long-term cognitive decline, an increase in morbidity and mortality as well as extended hospital stays. Delirium prevention and treatment options are currently limited. This study will evaluate the effect of transcranial electrical stimulation (tES) on the incidence of POD. Methods: We will perform a randomized, double-blind, sham-controlled trial using single-session postoperative application of tES in the recovery room in 225 patients (> 65 years) undergoing elective major surgery. Patients will be randomly allocated (ratio 1:1:1) to one of three study groups: (1) alpha-tACS over posterior parietal cortex [2 mA, 20 min], (2) anodal tDCS over left dorsolateral prefrontal cortex [2 mA, 20 min], (3) sham [2 mA, 30 s]. Delirium will be screened twice daily with the 3-min diagnostic interview Confusion Assessment Method (3D-CAM) in the 5 days following surgery. The primary outcome is the incidence of POD defined as at least one positive screening during the five first postoperative days compared between tACS and sham groups. Secondary outcomes include delirium severity, duration, phenotype, postoperative pain, postoperative nausea and vomiting, electroencephalographic (EEG) markers, and fluid biomarkers. Discussion: If effective, tES is a novel, easily applicable, non-invasive method to prevent the occurrence of POD. The comprehensive neurophysiological and biofluid assessments for markers of (neuro-)inflammation and neurodegeneration will shed light on the pathomechanisms behind POD and further elucidate the (after-)effects of tES. The potential implications for the postoperative recovery comprise enhanced patient safety, neurocognitive outcome, perioperative manageability but also reduced healthcare costs. Trial registration: German Clinical Trial Registry DRKS00033703. Registered on February 23, 2024. [ABSTRACT FROM AUTHOR]

Dysphagia is a frequent and life-threatening complication of multiple sclerosis (MS). Swallowing disturbances may be present at all stages of MS, although their prevalence increases with age, with disease duration, and in progressive phenotypes. The pathophysiology of dysphagia in MS is likely due to a combination of factors, including the involvement of corticobulbar tracts, the cerebellum, and the brainstem. Accurate diagnosis and early management of swallowing disorders improve quality of life and may delay complications or invasive therapeutic interventions. Here we provide an overview of the pathophysiology, the assessment, and the management of MS dysphagia, also examining the possible role of novel therapeutic strategies. Although studies using imaging and neurophysiological techniques have contributed to better characterize swallowing alterations in MS, the treatment of dysphagia is still challenging. Rehabilitation represents the main therapeutic approach for swallowing disorders. Recently, some innovative neurophysiological approaches, such as pharyngeal electrical stimulation (PES), repetitive transcranial magnetic stimulation (rTMS), and transcranial direct current stimulation (tDCS), have been proposed as a supplement to swallowing therapy in different neurological conditions. However, only few studies have explored the role of neuromodulation for MS dysphagia. [ABSTRACT FROM AUTHOR]

Introduction: Impulsivity, a tendency to act rashly and without forethought, is a core feature of many mental disorders that has been implicated in suicidality and offending behaviours. While research supports the use of non-invasive brain stimulation (NIBS) techniques, such as transcranial direct current stimulation (tDCS), to modulate brain functions, no studies specifically reviewed the use of combined cognitive training and NIBS to modulate impulsivity. Methods: We aimed to conduct a systematic review and meta-analysis to synthesise the literature on the use of combined cognitive training and NIBS to modulate impulsivity and its subdomains (motor, delay discounting, reflection). We searched Scopus, PsychInfo, Medline, and Cinahl electronic databases, dissertations database, and Google scholar up to September 2024. Results: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, four randomised controlled studies involving the use of combined cognitive training and tDCS in 127 subjects were included in the study. These studies included subjects with substance use disorders, obesity, and Parkinson's disease. Meta-analysis showed that combined cognitive training and tDCS had no statistically significant effects on motor impulsivity as measured using reaction times on the Stop Signal Task and Go/No Go tasks. One study that measured impulsiveness scores on a delay discounting task also showed no significant results. No studies measured reflection or cognitive impulsivity. Discussion: There is a dearth of literature on the use of combined cognitive training and NIBS for impulsivity. This in conjunction of clinical heterogeneity across studies makes it difficult to draw definitive conclusions about the neuromodulation of impulsivity and its subdomains using combined cognitive training and NIBS. The findings of this study highlight the need to conduct more studies in the field. Systematic review registration: https://www.crd.york.ac.uk/prospero/ , identifier CRD 42024511576. [ABSTRACT FROM AUTHOR]

Background: Implicit motor sequence learning (IMSL) is a cognitive function that allows us to execute multiple movements in a specific sequential order and plays a crucial role in our daily functional activities. Although the role of the basal ganglia network in IMSL is well-established, the exact involvement of the cerebellar network is less clear. Aim: Here, we aimed to address this issue by investigating the effects of cerebellar transcranial direct-current stimulation (tDCS) on IMSL. Methods: In this sham-controlled, crossover study in 45 healthy young adults, we used mixed-effects models to analyze sequence-specific (primary outcome) and general learning effects (secondary outcome) in the acquisition (during tDCS), short- (five minutes post-tDCS) and long-term consolidation (one week post-tDCS) phases of IMSL, as measured by the serial reaction time (SRT) task. Results: Analyses based on response times (RTs) revealed that anodal tDCS over the cerebellum significantly increased sequence-specific learning during acquisition, compared to sham (anodal: M = 38.24 ms, sham: M = 26.78 ms, p = 0.032); did not affect general learning; and significantly slowed overall RTs (anodal: M = 362.03 ms, sham: M = 356.37 ms, p = 0.049). Accuracy-based analyses revealed that anodal tDCS reduced the probability of correct responses occurring in random trials versus sequential trials by 1.17%, p = 0.009, whereas sham tDCS had no effect, p = 0.999. Conclusion: Our finding of enhanced sequence-specific learning, but not general learning, suggests that the cerebellar network not only plays a role in error correction processes, but also serves a sequence-specific function within the integrated motor learning network that connects the basal ganglia and cerebellum. [ABSTRACT FROM AUTHOR]

Introduction: Neuropsychiatric symptoms such as depression and anxiety are a significant burden on patients with multiple sclerosis (MS). Their pathophysiology is complex and yet to be fully understood. There is an urgent need for non-invasive treatments that directly target the brain and help patients with MS. One such possible treatment is transcranial direct current stimulation (tDCS), a popular and effective non-invasive brain stimulation technique. Methods: This mechanistic review explores the efficacy of tDCS in treating depression and anxiety in MS while focusing on the underlying mechanisms of action. Understanding these mechanisms is crucial, as neuropsychiatric symptoms in MS arise from complex neuroinflammatory and neurodegenerative processes. This review offers insights that may direct more focused and efficient therapeutic approaches by investigating the ways in which tDCS affects inflammation, brain plasticity, and neural connections. Searches were conducted using the PubMed/Medline, ResearchGate, Cochrane, and Google Scholar databases. Results: The literature search yielded 11 studies to be included in this review, with a total of 175 patients participating in the included studies. In most studies, tDCS did not significantly reduce depression or anxiety scores as the studied patients did not have elevated scores indicating depression and anxiety. In the few studies where the patients had scores indicating mild/moderate dysfunction, tDCS was more effective. The risk of bias in the included studies was assessed as moderate. Despite the null or near-null results, tDCS may still prove to be an effective treatment option for depression and anxiety in MS, because tDCS produces a neurobiological effect on the brain and nervous system. To facilitate further work, several possible mechanisms of action of tDCS have been reported, such as the modulation of the frontal–midline theta, reductions in neuroinflammation, the modulation of the HPA axis, and cerebral blood flow regulation. Conclusions: Although tDCS did not overall demonstrate positive effects in reducing depression and anxiety in the studied MS patients, the role of tDCS in this area should not be underestimated. Evidence from other studies indicates the effectiveness of tDCS in reducing depression and anxiety, but the studies included in this review did not include patients with sufficient depression or anxiety. Future studies are needed to confirm the effectiveness of tDCS in neuropsychiatric dysfunctions in MS. [ABSTRACT FROM AUTHOR]

The cerebral cortex, as the pinnacle of human complexity, poses formidable challenges to contemporary neuroscience. Recent advancements in non-invasive brain stimulation have been pivotal in enhancing human locomotor functions, a burgeoning area of interest in exercise science. Techniques such as transcranial direct current stimulation, transcranial alternating current stimulation, transcranial random noise stimulation, and transcranial magnetic stimulation are widely recognized for their neuromodulator capabilities. Despite their broad applications, these methods are not without limitations, notably in spatial and temporal resolution and their inability to target deep brain structures effectively. The advent of innovative non-invasive brain stimulation modalities, including transcranial focused ultrasound stimulation and temporal interference stimulation technology, heralds a new era in neuromodulation. These approaches offer superior spatial and temporal precision, promising to elevate athletic performance, accelerate sport science research, and enhance recovery from sports-related injuries and neurological conditions. This comprehensive review delves into the principles, applications, and future prospects of non-invasive brain stimulation in the realm of exercise science. By elucidating the mechanisms of action and potential benefits, this study aims to arm researchers with the tools necessary to modulate targeted brain regions, thereby deepening our understanding of the intricate interplay between brain function and human behavior. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to evaluate the effectiveness of two non-invasive brain stimulation (NIBS) methods, repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS), on spasticity in post-stroke patients with respect to patient age and muscle type. Methods: This meta-analysis was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. PUBMED (MEDLINE), Web of Science, Cochrane Library, and ExcerptaMedica Database (EMBASE) were searched for all randomized controlled trials (RCTs) published before December 2023. Results: In patients with spasticity after stroke, both rTMS (SMD: -0.56, CI95%: -0.81, -0.31, P<0.0001) and tDCS (SMD: -0.74, CI95%: -0.89, -0.59, P=0.005) significantly reduced the modified Ashworth Scale (MAS) compared with the control group. rTMS and tDCS were more effective in patients < 60 years than those > 60 years. Both rTMS and tDCS were effective against upper limb spasticity, particularly in patients aged < 60 years. Chronicity of stroke did not affect the benefit of rTMS to reduce spasticity although tDCS was more effective at 2 months after stroke onset. The reduction in spasticity in patients with supratentorial lesions was demonstrated by tDCS. The effectiveness of rTMS in spasticity reduction was not affected by the stimulation rate, but the use of tDCS at < 2 mA significantly decreased spasticity. Anodal stimulation (tDCS) reduced spasticity after stroke, especially in patients < 60 years of age. Other therapies, such as robotic therapy, the use of virtual reality, and electroacupuncture, were less effective against spasticity than conventional physical therapy combined with tDCS. The effectiveness of rTMS in spasticity reduction was not affected by the level of development, although tDCS was more successful in developing countries. Conclusions: Our findings suggest that NIBS should consider age, methods, and muscle type when treating patients with limb spasticity after stroke. [ABSTRACT FROM AUTHOR]

Cerebellar transcranial direct current stimulation (ctDCS) has emerged as a promising, non-invasive, and safe neuromodulatory intervention capable of reducing ataxia symptoms and restoring cerebellum-motor connectivity. However, previous studies have only applied ctDCS in isolation, without association with specific training. This study aimed to assess the effect of ctDCS combined with gait training on functional mobility, balance, and symptoms and severity of ataxia. A randomized, triple-blind, sham-controlled, bi-center clinical trial was conducted with forty-four adults with cerebellar ataxia. Volunteers were randomized to receive five daily sessions of either real ctDCS (n = 11; 2 mA for 25 min) or sham ctDCS (n = 11) during gait training. Functional mobility, balance, and symptoms and severity of ataxia were assessed using the Time Up and Go test, the MiniBESTest, and the Scale for the Assessment and Rating of Ataxia (SARA), respectively, before and after the interventions. Both groups showed improvement in functional mobility, but there was no significant difference between the ctDCS and sham groups. However, the ctDCS group demonstrated significant improvements in cerebellar ataxia severity as reflected by SARA scores, particularly in tests of stance, sitting, speech disturbance, nose-finger test, and heel-shin slide test. Notably, no improvements were observed in balance. This study indicates that while ctDCS combined with gait training may improve specific symptoms of cerebellar ataxia, it does not significantly enhance overall functional mobility compared to sham treatment. [ABSTRACT FROM AUTHOR]

The emotional and cognitive cerebellum has been explored by several studies in the past years. Recent evidence suggested the possible contribution of the cerebellum in processing emotional prosody, namely the ability to comprehend the emotional content of a given vocal utterance, likely mediated by anatomical and functional cerebello-prefrontal connections. In the present study, the involvement of a functional cerebello-prefrontal network in recognising emotional prosody was assessed by combining non-invasive anodal transcranial direct current stimulation (tDCS) over the right or the left cerebellum and functional Near Infrared Spectroscopy of the prefrontal cortex, in a double-blind within-subject experimental design on healthy participants. The results showed that right and, to a less extent, left cerebellar tDCS (as compared to sham stimulation) reduced neural activation in the prefrontal cortex while accuracy and reaction times at the vocal recognition task remained unchanged. These findings highlight functional properties of the cerebello-frontal connections and the psychophysiological effects of cerebellar brain stimulation, with possible clinical applications in psychiatric and neurological conditions. [ABSTRACT FROM AUTHOR]

Background: In the last few years, transcranial alternating current stimulation (tACS) has attracted attention as a promising approach to interact with ongoing oscillatory cortical activity and, consequently, to enhance cognitive and motor processes. While tACS findings are limited by high variability in young adults' responses, its effects on brain oscillations in older adults remain largely unexplored. In fact, the modulatory effects of tACS on cortical oscillations in healthy aging participants have not yet been investigated extensively, particularly during movement. This study aimed to examine the after-effects of 20 Hz and 70 Hz High-Definition tACS on beta oscillations both during rest and movement. Methods: We recorded resting state EEG signals and during a handgrip task in 15 healthy older participants. We applied 10 min of 20 Hz HD-tACS, 70 Hz HD-tACS or Sham stimulation for 10 min. We extracted resting-state beta power and movement-related beta desynchronization (MRBD) values to compare between stimulation frequencies and across time. Results: We found that 20 Hz HD-tACS induced a significant reduction in beta power for electrodes C3 and CP3, while 70 Hz did not have any significant effects. With regards to MRBD, 20 Hz HD-tACS led to more negative values, while 70 Hz HD-tACS resulted in more positive ones for electrodes C3 and FC3. Conclusions: These findings suggest that HD-tACS can modulate beta brain oscillations with frequency specificity. They also highlight the focal impact of HD-tACS, which elicits effects on the cortical region situated directly beneath the stimulation electrode. [ABSTRACT FROM AUTHOR]

Purpose: To examine the effects of single-dose anodal tDCS on isometric maximal voluntary contraction (MVC) and isometric endurance performance in lower limb exercises with healthy adults. Methods: For this systematic review and meta-analysis, we searched PubMed, ISI Web of Science, Scopus, and CINAHL for studies published between database inception and June 11, 2024. All randomized controlled trials on anodal tDCS interventions for MVC and isometric endurance in lower limb exercises were included, with no date restrictions. The quality of the evidence was assessed using the Jadad Scale, and the certainty of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation approach. The Open Science Framework registered the protocol in June 2024 (DOI https://doi.org/10.17605/OSF.IO/AG93M). Results: 20 interventions were included, comprising 15 for MVC and 5 for 'Time to Task Failure' (TTF), which refers to isometric endurance performance measured in seconds. The findings showed no difference in the MVC (SMD = 0.06; 95% CI = − 0.14, 0.25; P = 0.57) and TTF performance (WMD = 0.07; 95% CI = − 0.26, 0.40; P = 0.68). Conclusion: The current meta-analysis indicated that anodal tDCS did not increase isometric MVC and isometric endurance performance in lower limb exercises in healthy adults. [ABSTRACT FROM AUTHOR]

Background: Transcranial direct current stimulation (tDCS) and repetitive transcranial magnetic stimulation (rTMS) are common non-invasive brain stimulation (NIBS) methods for functional recovery after stroke. Motor imagery (MI) can be used in the rehabilitation of limb motor function after stroke, but its effectiveness remains to be rigorously established. Furthermore, there is a growing interest in the combined application of NIBS with MI, yet the evidence regarding its impact on the recovery of upper limb function after stroke is inconclusive. This meta-analysis aimed to demonstrate whether combining the two is superior to NIBS alone or MI alone to provide a reference for clinical decision-making. Methods: PubMed, EMBASE, Cochrane Library, Web of Science, Science Direct, CNKI, WANFANG, and VIP databases were searched for randomized controlled trials on the effects of MI combined NIBS in motor function recovery after stroke until February 2024. The outcomes of interest were associated with body functions or structure (impairment) and activity (functional). The primary outcome was assessed with the Fugl-Meyer assessment of the upper extremity (FMA-UE) for motor function of the upper limbs and the modified Barthel Index (MBI) for the ability to perform daily living activities. For secondary outcomes, functional activity level was measured using wolf motor function test (WMFT) and action research arm test (ARAT), and cortical excitability was assessed using cortical latency of motor evoked potential (MEP-CL) and central motor conduction time (CMCT). The methodological quality of the selected studies was evaluated using the evidence‑based Cochrane Collaboration's tool. A meta-analysis was performed to calculate the mean differences (MD) or the standard mean differences (SMD) and 95% confidence intervals (CI) with random-effect models. Results: A total of 14 articles, including 886 patients, were reviewed in the meta-analysis. In comparison with MI or NIBS alone, the combined therapy significantly improved the motor function of the upper limbs (MD = 5.43; 95% CI 4.34–6.53; P < 0.00001) and the ability to perform activities of daily living (MD = 11.07; 95% CI 6.33–15.80; P < 0.00001). Subgroup analyses showed an interaction between the stage of stroke, the type of MI, and the type of NIBS with the effect of the combination therapy. Conclusion: The combination of MI and NIBS may be a promising therapeutic approach to enhance upper limb motor function, functional activity, and activities of daily living after stroke. Systematic registration: PROSPERO registration CRD42023493073. [ABSTRACT FROM AUTHOR]

Background: Parkinson's disease (PD) induces progressive deficits in motor and cognitive functions as well as impaired dual-task performance requiring both motor and cognitive functions. This systematic review and meta-analysis evaluated the effects of non-invasive brain stimulation (NIBS) on dual-task performance in patients with PD. Methods: 11 studies met the following inclusion criteria: (a) patients with PD, (b) NIBS intervention, (c) comparison with the sham stimulation group, (d) motor and cognitive performance outcomes during dual tasks, and (e) randomized controlled trials with parallel or crossover designs. Individual effect size (i.e., comparison) was quantified by comparing motor and cognitive performances changes during dual tasks between active NIBS and sham stimulation conditions. Thus, higher values of the overall effect size indicate more improvements in either motor or cognitive performances after NIBS. Moreover, moderator variable analyses determined whether NIBS effects on dual-task performances differed depending on targeted brain regions. Finally, meta-regression analyses determined whether NIBS effects on dual-task performances were associated with demographic characteristics. Results: The random-effects model meta-analysis revealed that NIBS significantly improved motor (73 comparisons from 11 studies) and cognitive (12 comparisons from four studies) performances during dual tasks in patients with PD. Specifically, anodal transcranial direct current stimulation protocols on the dorsolateral prefrontal cortex were effective. Moreover, greater improvements in motor performance during dual tasks significantly correlated with decreased age and increased proportion of females, respectively. Conclusion: This meta-analysis suggests that excitatory stimulation on the dorsolateral prefrontal cortex may be effective for improving dual-task performance in patients with PD. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to systematically assess the clinical efficacy of non-invasive brain stimulation (NIBS) for treating post-stroke sleep disorders (PSSD). Methods: We conducted thorough literature search across multiple databases, including PubMed, Web of Science, EmBase, Cochrane Library, Scopus, China Biology Medicine (CBM); China National Knowledge Infrastructure (CNKI); Technology Periodical Database (VIP), and Wanfang Database, focusing on RCTs examining NIBS for PSSD. Meta-analyses were performed using RevMan 5.4 and Stata 14. Results: Eighteen articles were reviewed, including 16 on repetitive Transcranial Magnetic Stimulation (rTMS), one on Theta Burst Stimulation (TBS), and two on transcranial Direct Current Stimulation (tDCS). Meta-analysis results indicated that rTMS within NIBS significantly improved the Pittsburgh Sleep Quality Index (PSQI) score (MD = −1.85, 95% CI [−2.99, −0.71], p < 0.05), the 17-item Hamilton Depression Rating Scale (HAMD-17) score [MD = −2.85, 95% CI (−3.40, −2.30), p < 0.05], and serum brain-derived neurotrophic factor (BDNF) levels [MD = 4.19, 95% CI (2.70, 5.69), p < 0.05], while reducing the incidence of adverse reactions [RR = 0.36, 95% CI (0.23, 0.55), p < 0.05]. TBS significantly improved the PSQI score in patients with PSSD (p < 0.05). Conversely, tDCS significantly improved the HAMD-17 score in PSSD patients [MD = −1.52, 95% CI (−3.41, −0.64), p < 0.05]. Additionally, rTMS improved sleep parameters, including Stage 2 sleep (S2%) and combined Stage 3 and 4 sleep (S3 + S4%) (p < 0.05), while tDCS improved total sleep time (TST) and sleep efficiency (SE) (p < 0.05).Subgroup analysis results indicated: (1) Both LF-rTMS and HF-rTMS improved PSQI scores (p < 0.05). (2) Both rTMS combined with medication and rTMS alone improved PSQI scores (p < 0.05). Compared to the sham/blank group, the rTMS group showed improvements in SE, sleep latency (SL), S1%, S3 + S4%, and REM sleep (REM%). The rTMS combined with medication group showed improved SL compared to the medication-only group (p < 0.05). Conclusion: NIBS effectively improves sleep quality, structure, depression levels, and BDNF levels in PSSD patients, while also being safe. Further investigations into the potential of NIBS in PSSD treatment may provide valuable insights for clinical applications. Systematic review registration: https://www.crd.york.ac.uk/prospero/, CRD42023485317. [ABSTRACT FROM AUTHOR]

Background: Temporal interference (TI) stimulation, an innovative non-invasive brain stimulation approach, has the potential to activate neurons in deep brain regions. However, the dynamic mechanisms underlying its neuromodulatory effects are not fully understood. This study aims to investigate the effects of TI stimulation on dynamic functional connectivity (dFC) in the motor cortex. Methods: 40 healthy adults underwent both TI and tDCS in a double-blind, randomized crossover design, with sessions separated by at least 48 h. The total stimulation intensity of TI is 4 mA, with each channel's intensity set at 2 mA and a 20 Hz frequency difference (2 kHz and 2.02 kHz). The tDCS stimulation intensity is 2 mA. Resting-state functional magnetic resonance imaging (rs-fMRI) data were collected before, during, and after stimulation. dFC was calculated using the left primary motor cortex (M1) as the region of interest (ROI) and analyzed using a sliding time-window method. A two-way repeated measures ANOVA (group × time) was conducted to evaluate the effects of TI and tDCS on changes in dFC. Results: For CV of dFC, significant main effects of stimulation type (P = 0.004) and time (P < 0.001) were observed. TI showed lower CV of dFC than tDCS in the left postcentral gyrus (P < 0.001). TI-T2 displayed lower CV of dFC than TI-T1 in the left precentral gyrus (P < 0.001). For mean dFC, a significant main effect of time was found (P < 0.001). TI–T2 showed higher mean dFC than tDCS-T2 in the left postcentral gyrus (P = 0.018). Within-group comparisons revealed significant differences between time points in both TI and tDCS groups, primarily in the left precentral and postcentral gyri (all P < 0.001). Results were consistent across different window sizes. Conclusion: 20 Hz TI stimulation altered dFC in the primary motor cortex, leading to a significant decreasing variability and increasing mean connectivity strength in dFC. This outcome indicates that the 20 Hz TI frequency interacted with the motor cortex's natural resonance. [ABSTRACT FROM AUTHOR]

Neurodevelopmental disorders such as attention deficit and/or hyperactivity disorder (ADHD) and schizophrenia are characterized by core impairment in executive functions (EF). Despite the development of various behavioral interventions to enhance EF, the evidence is still scarce. Alternatively, non-invasive brain stimulation tools such as transcranial alternating current stimulation (tACS) has emerged as a potential strategy to alleviate cognitive deficits. Previous studies have demonstrated the safety, feasibility, and efficacy of one single tACS session in different clinical populations. However, the effects of tACS appear limited and need to be sustained to be considered an effective cognitive neurorehabilitation tool. Recent studies have used home-based, repeated tACS sessions in individuals with neurodegenerative diseases. To our knowledge, the safety and feasibility of such an intensive protocol remains to be tested in a younger population with neurodevelopmental disorders. Using a randomized double-blind sham-controlled design, we administered home-based, repeated tACS sessions to seven individuals aged 14–25 with 22q11.2 deletion syndrome (22q11.2DS), which confers an increased risk for neurodevelopmental disorders. We aimed to assess the safety, tolerability, and feasibility of tACS. Findings from this ongoing clinical trial revealed a favorable safety profile, with frequent yet transient and mainly mild adverse effects. The intervention proved to be feasible, shown by very high adherence rates and positive user experiences. Future studies should therefore investigate whether prolonged exposure to tACS can lead to long-lasting cognitive outcomes. Clinical trial registration: ClinicalTrials.gov, identifier NCT05664412. [ABSTRACT FROM AUTHOR]

Background: This systematic review and meta‐analysis aimed to assess the effectiveness of non‐invasive brain stimulation (NIBS), including repetitive transcranial magnetic stimulation (rTMS) and transcranial electrical stimulation (tES), as a neurological intervention for degenerative cerebellar ataxia (DCA) based on preregistration (PROSPERO: CRD42023379192). Objective: We aimed to explore clinical outcomes and examine the parameters associated with NIBS efficacy in DCA patients. Methods: The PubMed, Cochrane Library, CHINAL, and PEDro databases were searched for relevant randomized controlled trials (RCTs). Data extraction, quality assessment, and heterogeneity analyses were conducted; the Grading, Recommendations, Assessment, Development, and Evaluation was used to assess the quality of evidence and a meta‐analysis was performed. Results: Seventeen RCTs that included 661 patients on the scale for assessment and rating of ataxia (SARA) and 606 patients on the International Cooperative Ataxia Rating Scale (ICARS) were included. These RCTs showed a serious risk of bias (RoB) and low certainty of evidence for both outcomes. NIBS significantly reduced SARA (MD = −2.49, [95% confidence interval: −3.34, −1.64]) and ICARS (−5.27 [−7.06, −3.47]); the subgroup analysis showed significant effects: rTMS and tES reduced both outcomes. However, there were no significant differences in the effects of rTMS and tES. Additional subgroup analysis indicated the impact of rTMS frequency and the total number of tES sessions on ataxia. Conclusion: Non‐invasive brain stimulation may reduce ataxia in DCA patients, but the estimated effect size may change in future studies because the RoB was serious and the certainty of evidence was low, and the heterogeneity was high. To establish evidence for selecting NIBS methods and parameters, continued high‐quality RCTs are required. [ABSTRACT FROM AUTHOR]

Non-invasive brain stimulation (NIBS) techniques are designed to precisely and selectively target specific brain regions, thus enabling focused modulation of neural activity. Among NIBS technologies, low-intensity transcranial focused ultrasound (tFUS) has emerged as a promising new modality. The application of tFUS can safely and non-invasively stimulate deep brain structures with millimetric precision, offering distinct advantages in terms of accessibility to non-cortical regions over other NIBS methods. However, to date, several tFUS aspects still need to be characterized; furthermore, there are only a handful of studies that have utilized tFUS in psychiatric populations. This narrative review provides an up-to-date overview of key aspects of this NIBS technique, including the main components of a tFUS system, the neuronavigational tools used to precisely target deep brain regions, the simulations utilized to optimize the stimulation parameters and delivery of tFUS, and the experimental protocols employed to evaluate the efficacy of tFUS in psychiatric disorders. The main findings from studies in psychiatric populations are presented and discussed, and future directions are highlighted. [ABSTRACT FROM AUTHOR]

Non‐invasive brain stimulation techniques offer therapeutic potential for neurological and psychiatric disorders. However, current methods are often limited in their stimulation depth. The novel transcranial temporal interference stimulation (tTIS) aims to overcome this limitation by non‐invasively targeting deeper brain regions. In this study, we aimed to evaluate the efficacy of tTIS in modulating alpha activity during a mental rotation task. The effects of tTIS were compared with transcranial alternating current stimulation (tACS) and a sham control. Participants were randomly assigned to a tTIS, tACS, or sham group. They performed alternating blocks of resting and mental rotation tasks before, during, and after stimulation. During the stimulation blocks, participants received 20 min of stimulation adjusted to their individual alpha frequency (IAF). We assessed shifts in resting state alpha power, event‐related desynchronization (ERD) of alpha activity during mental rotation, as well as resulting improvements in behavioral performance. Our results indicate tTIS and tACS to be effective in modulating cortical alpha activity during mental rotation, leading to an increase in ERD from pre‐ to poststimulation as well as compared to sham stimulation. However, this increase in ERD was not correlated with enhanced mental rotation performance, and resting state alpha power remained unchanged. Our findings underscore the complex nature of tTIS and tACS efficacy, indicating that stimulation effects are more observable during active cognitive tasks, while their impacts are less pronounced on resting neuronal systems. Our study adds to the limited human research on the novel tTIS technique, which holds the potential for non‐invasive deep brain stimulation. We show that while tTIS and tACS can modulate cortical alpha activity during an active cognitive task, they do not improve behavioral performance or affect resting state alpha power. This underscores the task‐specific effectiveness of these techniques, suggesting their therapeutic potential is most effective during active cognitive engagement. [ABSTRACT FROM AUTHOR]

Recent studies have demonstrated changes in athletes brain imaging across a competitive season due to repeated head impacts during collision sports. However, there is no data reporting cortical activity in elite female rugby sevens players. There is scant literature on the effects of high-definition (HD)-transcranial direct current stimulation (tDCS) on cortical activity responses at different time points (TP) across the competitive season on the responsiveness of spectral band frequencies for HD-tDCS stimulation. This study examined the cortical activity of elite female rugby sevens players prior to pre-season (TP1) and following five months of training and competition (TP2), and the acute effects of HD-tDCS on cortical activity parameters. For each TP, the squad was randomly allocated to the HD-tDCS sham or the HD-tDCS anodal (active) stimulation groups. The Stroop task was performed for approximately 15 min prior to HD-tDCS (Stroop task-PRE). Following completion of the Stroop task-PRE, participants received 20-minutes of HD-tDCS stimulation and then performed the Stroop task (Stroop task-POST). A diminished responsiveness of cortical activity to the perturbation (HD-tDCS) for TP2 (vs. TP1) was observed, with cortical rhythms exhibiting a relative decline in faster bands (alpha, beta, and gamma), while slower bands (delta and theta) increased its proportional contribution to cortical activity. This discovery implies a potential alteration in the neural substrate's responsiveness to neuromodulation, likely influenced by the cumulative effects of repeated head impacts. The diminished responsiveness to HD-tDCS prompts significant considerations for the application of neuromodulation techniques in athletes participating in contact/collision sports. [ABSTRACT FROM AUTHOR]

Objective. The objective of this study was to explore the effect of transcranial direct current stimulation (tDCS) combined with hand grip strengthening exercises in amateur badminton players. Materials and methods. This study was a participant-blinded, randomized controlled trial. Thirty amateur badminton players, aged 8–20 years with a minimum playing experience of 6 months, were included. Hand grip strength (HGS) was measured at baseline, Day 1, Day 4, Day 8, and Day 12. Results. The results of the present study showed no significant difference in hand grip strength between the groups. The overall interaction effect between the groups was found to be insignificant (p = 0.722). However, the overall interaction effect within the group was significant (p = 0.011*). Multiple comparisons revealed the greatest improvement in HGS at Day 12 compared to the baseline value. Conclusion. The application of anodal tDCS combined with HGS training was ineffective in improving hand grip strength in amateur badminton players. [ABSTRACT FROM AUTHOR]

Non-invasive brain stimulation (NIBS), including repetitive transcranial magnetic stimulation (rTMS), continuous theta-burst stimulation (cTBS), and transcranial direct current stimulation (tDCS), is an emerging intervention that has been used to treat various mental illnesses. However, previous studies have not comprehensively compared the efficacies of various NIBS modalities in alleviating anxiety symptoms among patients with generalized anxiety disorder (GAD). Therefore, this study conducted a systematic review and meta-analysis to assess the efficacy of NIBS for patients with GAD. A systematic search of four major bibliographic databases (Embase, PubMed, Web of Science and The Cochrane Library) was conducted from inception dates to November 26, 2023 to identify eligible studies. The data were analyzed using a random-effects model. Seven randomized controlled trials (RCTs) were included in the meta-analysis. Significant differences were found in changes in Hamilton anxiety rating scale (HARS) scores, study-defined response, and remission between the intervention and control groups. Moreover, the intervention groups experienced a significantly higher frequency of headaches. The results revealed that interventions improved GAD compared to control groups. cTBS and rTMS exhibited better treatment efficacy than tDCS, which did not appear to have a significant therapeutic effect. Longer follow-up periods and larger sample sizes are required in future RCTs. This meta-analysis was conducted in accordance with PRISMA guidelines and registered at PROSPERO (https://www.crd.york.ac.uk/PROSPERO/ , CRD42023466285). • Systematic review and meta-analysis of NIBS techniques, including cTBS, rTMS, and tDCS, for treating GAD. • NIBS significantly reduces anxiety symptoms and improves response and remission rates. • The efficacy is notably contingent on the stimulation types employed. • Discerning headaches as an adverse event exhibited notable statistical disparities. [ABSTRACT FROM AUTHOR]

Background: Caloric vestibular stimulation (CVS) is a well-established neurological diagnostic technique that also induces many phenomenological modulations, including reductions in phantom limb pain (PLP), spinal cord injury pain (SCIP), and central post-stroke pain. Objective: We aimed to assess in a variety of persistent pain (PP) conditions (i) short-term pain modulation by CVS relative to a forehead ice pack cold-arousal control procedure and (ii) the duration and repeatability of CVS modulations. The tolerability of CVS was also assessed and has been reported separately. Methods: We conducted a convenience-based non-randomised single-blinded placebo-controlled study. Thirty-eight PP patients were assessed (PLP, n = 8; SCIP, n = 12; complex regional pain syndrome, CRPS, n = 14; non-specific PP, n = 4). Patients underwent 1–3 separate-day sessions of iced-water right-ear CVS. All but four also underwent the ice pack procedure. Analyses used patient-reported numerical rating scale pain intensity (NRS-PI) scores for pain and allodynia. Results: Across all groups, NRS-PI for pain was significantly lower within 30 min post-CVS than post-ice pack (p < 0.01). Average reductions were 24.8% (CVS) and 6.4% (ice pack). CRPS appeared most responsive to CVS, while PLP and SCIP responses were less than expected from previous reports. The strongest CVS pain reductions lasted hours to over three weeks. CVS also induced substantial reductions in allodynia in three of nine allodynic CRPS patients, lasting 24 h to 1 month. As reported elsewhere, only one patient experienced emesis and CVS was widely rated by patients as a tolerable PP management intervention. Conclusions: Although these results require interpretative caution, CVS was found to modulate pain relative to an ice pack control. CVS also modulated allodynia in some cases. CVS should be examined for pain management efficacy using randomised controlled trials. [ABSTRACT FROM AUTHOR]

Introduction: In individuals with patellofemoral pain (PFP), addressing increased knee valgus during weight-bearing activities typically involves strengthening weak hip muscles. However, recent literature highlights the role of altered descending central control in abnormal movements associated with PFP. While transcranial direct current stimulation (tDCS) has demonstrated the capacity to enhance neuroplasticity, its application targeting the corticomotor function of gluteal muscles in PFP remains unexplored. This study aimed to investigate the effects of combining bimodal tDCS with exercise on frontal plane kinematics in individuals with PFP. The hypothesis was that bimodal tDCS, specifically targeting the corticomotor function of the gluteal muscles, would augment the effectiveness of exercise interventions in improving frontal plane kinematics compared to sham stimulation. Methods: Ten participants with PFP participated in two sessions involving either bimodal tDCS or sham stimulation, concurrently with hip strengthening exercises. Weight-bearing tasks, including single leg squat, single leg landing, single leg hopping, forward step-down, and lateral step-down, were performed and recorded before and after each session. Pain visual analog scale (VAS) scores were also documented. A one-way ANOVA with repeated measures was employed to compare kinematics, while a Friedman test was used to compare VAS across the three conditions (pre-test, post-tDCS, and post-Sham). Results: We observed no significant differences in trunk lean angle, hip and knee frontal plane projection angles, or dynamic valgus index among the three conditions during the five weight-bearing tasks. VAS scores did not differ across the three conditions. Discussion and conclusion: A single session of tDCS did not demonstrate immediate efficacy in enhancing frontal plane kinematics or relieving pain in individuals with PFP. Considering observed positive outcomes in other neurological and orthopedic populations with multi-session tDCS applications, suggesting potential cumulative effects, further research is essential to explore the effects of multi-session tDCS on weight-bearing movement and underlying neurophysiology in individuals with PFP. [ABSTRACT FROM AUTHOR]

Introduction: Bulimia nervosa (BN) is a disorder primarily affecting adolescent females, characterized by episodes of binge eating followed by inappropriate compensatory behaviors aimed at preventing weight gain, including self-induced vomiting and the misuse of diuretics, laxatives, and insulin. The precise etiology of BN remains unknown, with factors such as genetics, biological influences, emotional disturbances, societal pressures, and other challenges contributing to its prevalence. First-line treatment typically includes pharmacotherapy, which has shown moderate effectiveness. Neuroimaging evidence suggests that altered brain activity may contribute to the development of BN, making interventions that directly target the brain extremely valuable. One such intervention is repetitive transcranial magnetic stimulation (rTMS), a non-invasive stimulation technique that has been garnering interest in the medical community for many years. Methods: This review explores the use of rTMS in the treatment of BN. Searches were conducted in the PubMed/Medline, ResearchGate, and Cochrane databases. Results: Twelve relevant studies were identified. Analysis of the results from these studies reveals promising findings, particularly regarding key parameters in the pathophysiology of BN. Several studies assessed the impact of rTMS on binge episodes. While some studies did not find significant reductions, most reported decreases in binge eating and purging behaviors, with some cases showing complete remission. Reductions in symptoms of depression and food cravings were also demonstrated. However, results regarding cognitive improvement were mixed. The discussion focused heavily on potential mechanisms of action, including neuromodulation of brain networks, induction of neuroplasticity, impact on serotonergic dysfunction, anti-inflammatory action, and HPA axis modulation. rTMS was found to be a safe intervention with no serious side effects. Conclusions: rTMS in the treatment of BN appears to be a promising intervention that alleviates some symptoms characteristic of the pathophysiology of this disorder. An additional effect is a significant reduction in depressive symptoms. However, despite these findings, further research is required to confirm its effectiveness and elucidate the mechanisms of action. It is also recommended to further investigate the potential mechanisms of action described in this review. [ABSTRACT FROM AUTHOR]

Objective: Auditory hallucinations are the most frequently occurring psychotic symptom in schizophrenia. Continuous theta burst stimulation (cTBS) has been used as an adjuvant treatment for auditory hallucinations. This meta-analysis focused on randomized controlled clinical trials (RCTs) to assess the efficacy of adjuvant cTBS on auditory hallucinations in schizophrenia. Methods: We performed a comprehensive search of four international databases from their inception to January 14, 2024, to identify relevant RCTs that assessed the effects of adjuvant cTBS on auditory hallucinations. The key words included "auditory hallucinations", "continuous theta burst stimulation" and "transcranial magnetic stimulation". Inclusion criteria included patients with auditory hallucinations in schizophrenia or schizoaffective disorder. The Revised Cochrane risk-of-bias tool for randomized trials (RoB1) were used to evaluate the risk of bias and the Review Manager Software Version 5.4 was employed to pool the data. Results: A total of 4 RCTs involving 151 patients with auditory hallucinations were included in the analysis. The Cochrane risk of bias of these studies presented "low risk" in all items. Preliminary analysis showed no significant advantage of adjuvant cTBS over sham stimulation in reducing hallucinations [4 RCTs, n = 151; SMD: - 0.45 (95%CI: -1.01, 0.12), P = 0.13; I2 = 61%]. Subgroup analysis revealed that patients treated with adjuvant cTBS for more than 10 stimulation sessions and total number of pulses more than 6000 [3 RCTs, n = 87; SMD: -4.43 (95%CI: -8.22, - 0.63), P=0.02; I2 = 47%] had a statistically significant improvement in hallucination symptoms. Moreover, the rates of adverse events and discontinuation did not show any significant difference between the cTBS and sham group. Conclusions: Although preliminary analysis did not revealed a significant advantage of adjuvant cTBS over sham stimulation, subgroup analysis showed that specific parameters of cTBS appear to be effective in the treatment of auditory hallucinations in schizophrenia. Further large-scale studies are needed to determine the standard protocol of cTBS for treating auditory hallucinations. [ABSTRACT FROM AUTHOR]

• Effects of transcranial static magnetic stimulation (tSMS) are state-dependent. • tSMS increases cortical excitability if applied on an inhibited M1. • Aftereffects of tSMS originate at synaptic level. Aftereffects of non-invasive brain stimulation techniques may be brain state-dependent. Either continuous theta-burst stimulation (cTBS) as transcranial static magnetic field stimulation (tSMS) reduce cortical excitability. Our objective was to explore the aftereffects of tSMS on a M1 previously stimulated with cTBS. The interaction effect of two inhibitory protocols on cortical excitability was tested on healthy volunteers (n = 20), in two different sessions. A first application cTBS was followed by real-tSMS in one session, or sham-tSMS in the other session. When intracortical inhibition was tested with paired-pulse transcranial magnetic stimulation, LICI (ie., long intracortical inhibition) increased, although the unconditioned motor-evoked potential (MEP) remained stable. These effects were observed in the whole sample of participants regardless of the type of static magnetic field stimulation (real or sham) applied after cTBS. Subsequently, we defined a group of good-responders to cTBS (n = 9) on whom the unconditioned MEP amplitude reduced after cTBS and found that application of real-tSMS (subsequent to cTBS) increased the unconditioned MEP. This MEP increase was not found when sham-tSMS followed cTBS. The interaction of tSMS with cTBS seems not to take place at inhibitory cortical interneurons tested by LICI, since LICI was not differently affected after real and sham tSMS. Our results indicate the existence of a process of homeostatic plasticity when tSMS is applied after cTBS. This work suggests that tSMS aftereffects arise at the synaptic level and supports further investigation into tSMS as a useful tool to restore pathological conditions with altered cortical excitability. [ABSTRACT FROM AUTHOR]

Upper limb weakness following stroke poses a significant global psychosocial and economic burden. Non-invasive brain stimulation (NIBS) is a potential adjunctive treatment in rehabilitation. However, traditional approaches to rebalance interhemispheric inhibition may not be effective for all patients. The supportive role of the contralesional hemisphere in recovery of upper limb motor function has been supported by animal and clinical studies, particularly for those with severe strokes. This review aims to provide an overview of the facilitation role of the contralesional hemisphere for post-stroke motor recovery. While more studies are required to predict responses and inform the choice of NIBS approach, contralesional facilitation may offer new hope for patients in whom traditional rehabilitation and NIBS approaches have failed. [ABSTRACT FROM AUTHOR]

Numerous studies have demonstrated the potential of non-invasive brain stimulation (NIBS) techniques as a viable treatment option for cerebellar ataxia. However, there is a notable dearth of research investigating the efficacy of NIBS specifically for hereditary ataxia (HA), a distinct subgroup within the broader category of cerebellar ataxia. This study aims to conduct a comprehensive systematic review and meta-analysis in order to assess the efficacy of various NIBS methods for the treatment of HA. A thorough review of the literature was conducted, encompassing both English and Chinese articles, across eight electrical databases. The focus was on original articles investigating the therapeutic effectiveness of non-invasive brain stimulation for hereditary ataxia, with a publication date prior to March 2023. Subsequently, a meta-analysis was performed specifically on randomized controlled trials (RCTs) that fulfilled the eligibility criteria, taking into account the various modalities of non-invasive brain stimulation. A meta-analysis was conducted, comprising five RCTs, which utilized the Scale for the Assessment and Rating of Ataxia (SARA) as the outcome measure to evaluate the effects of transcranial magnetic stimulation (TMS). The findings revealed a statistically significant mean decrease of 1.77 in the total SARA score following repetitive TMS (rTMS) (p=0.006). Subgroup analysis based on frequency demonstrated a mean decrease of 1.61 in the total SARA score after high-frequency rTMS (p=0.05), while no improvement effects were observed after low-frequency rTMS (p=0.48). Another meta-analysis was performed on three studies, utilizing ICARS scores, to assess the impact of rTMS. The results indicated that there were no statistically significant differences in pooled ICARS scores between the rTMS group and the sham group (MD=0.51, 95%CI: -5.38 to 6.39; p=0.87). These findings align with the pooled results of two studies that evaluated alterations in post-intervention BBS scores (MD=0.74, 95%CI: -5.48 to 6.95; p=0.82). Despite the limited number of studies available, this systematic review and meta-analysis have revealed promising potential benefits of rTMS for hereditary ataxia. However, it is strongly recommended that further high-quality investigations be conducted in this area. Furthermore, the significance of standardized protocols for NIBS in future studies was also emphasized. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Patients with substance use disorders (SUDs) often suffer from cognitive dysfunction (CD), affecting their quality of life and daily functioning. Current treatments, including pharmacotherapy and psychotherapy, have limited efficacy and notable side effects. Transcranial direct current stimulation (tDCS), a non-invasive technique that modulates cortical activity, shows promise in improving cognitive function with minimal side effects and low cost, and could potentially serve as a valuable adjunct to existing therapies. This systematic review aims to evaluate the literature on the effectiveness of tDCS for CD in SUD patients to inform clinical practice and future research. Following PRISMA guidelines, the review includes studies that used tDCS for SUD-related CD. The criteria for inclusion encompassed participants aged 18 and older with a diagnosis of SUD, the use of tDCS (either conventional or high-definition), control groups receiving sham stimulation or no intervention, and cognitive outcome measures for substance-related cognitive function using validated tools. Databases searched were Ovid MEDLINE, PubMed, Web of Science, Embase, Scopus, and PsycINFO, with specific keywords. Twenty-two studies met the criteria, suggesting tDCS can improve cognitive functions in SUD patients, though results varied. Effectiveness may depend on the brain area targeted, stimulation parameters, task requirements, and individual differences. tDCS shows potential in treating SUD-related CD, but further research is needed to optimize stimulation protocols and address study variability. Future studies should use functional magnetic resonance imaging to explore the brain mechanisms by which tDCS improves cognitive function in SUDs and focus on larger, long-term trials to confirm efficacy and refine tDCS treatment parameters. [ABSTRACT FROM AUTHOR]

Both the primary motor cortex (M1) and the cerebellum are crucial for postural stability and deemed as potential targets for non‐invasive brain stimulation (NIBS) to enhance balance performance. However, the optimal target remains unknown. The purpose of this study was to compare the role of M1 and the cerebellum in modulating balance performance in young healthy adults using facilitatory 5 Hz repetitive transcranial magnetic stimulation (rTMS). Twenty‐one healthy young adults (mean age = 27.95 ± 1.15 years) received a single session of 5 Hz rTMS on M1 and the cerebellum in a cross‐over order with a 7‐day washout period between the two sessions. Three balance assessments were performed on the Biodex Balance system SD: Limits of Stability (LOS), modified Clinical Test of Sensory Interaction on Balance (mCTSIB), and Balance Error Scoring System (BESS). No significant effect of rTMS was found on the LOS. The effect of rTMS on the mCTSIB was mediated by stimulation target, proprioception, and vision (p =.003, ηp2 = 0.37). Cerebellar rTMS improved the mCTSIB sway index under eyes closed‐foam surface condition (p =.02), whereas M1 rTMS did not result in improvement on the mCTSIB. The effect of rTMS on the BESS was mediated by stimulation target, posture, and proprioception (p =.049, ηp2 = 0.14). Cerebellar rTMS enhanced reactive balance performance during most sensory deprived conditions. [ABSTRACT FROM AUTHOR]

Introduction: Transcranial direct current stimulation (tDCS) administers lowintensity direct current electrical stimulation to brain regions via electrodes arranged on the surface of the scalp. The core promise of tDCS is its ability to modulate brain activity and affect performance on diverse cognitive functions (affording causal inferences regarding regional brain activity and behavior), but the optimal methodological parameters for maximizing behavioral effects remain to be elucidated. Here we sought to examine the effects of 10 stimulation and experimental design factors across a series of five cognitive domains: motor performance, visual search, working memory, vigilance, and response inhibition. The objective was to identify a set of optimal parameter settings that consistently and reliably maximized the behavioral effects of tDCS within each cognitive domain. Methods: We surveyed tDCS effects on these various cognitive functions in healthy young adults, ultimately resulting in 721 effects across 106 published reports. Hierarchical Bayesian meta-regression models were fit to characterize how (and to what extent) these design parameters differentially predict the likelihood of positive/negative behavioral outcomes. Results: Consistent with many previous meta-analyses of tDCS effects, extensive variability was observed across tasks and measured outcomes. Consequently, most design parameters did not confer consistent advantages or disadvantages to behavioral effects--a domain-general model suggested an advantage to using within-subjects designs (versus between-subjects) and the tendency for cathodal stimulation (relative to anodal stimulation) to produce reduced behavioral effects, but these associations were scarcely-evident in domainspecific models. Discussion: These findings highlight the urgent need for tDCS studies to more systematically probe the effects of these parameters on behavior to fulfill the promise of identifying causal links between brain function and cognition. [ABSTRACT FROM AUTHOR]

Individuals suffering from long-COVID can present with "brain fog", which is characterized by a range of cognitive impairments, such as confusion, short-term memory loss, and difficulty concentrating. To date, several potential interventions for brain fog have been considered. Notably, no systematic review has comprehensively discussed the impact of each intervention type on brain fog symptoms. We included studies on adult (aged > 18 years) individuals with proven long- COVID brain-fog symptoms from PubMed, MEDLINE, Central, Scopus, and Embase. A search limit was set for articles published between 01/2020 and 31/12/2023. We excluded studies lacking an objective assessment of brain fog symptoms and patients with preexisting neurological diseases that affected cognition before COVID-19 infection. This review provided relevant information from 17 studies. The rehabilitation studies utilized diverse approaches, leading to a range of outcomes in terms of the effectiveness of the interventions. Six studies described noninvasive brain stimulation, and all showed improvement in cognitive ability. Three studies described hyperbaric oxygen therapy, all of which showed improvements in cognitive assessment tests and brain perfusion. Two studies showed that the use of Palmitoylethanolamide and Luteolin (PEA-LUT) improved cognitive impairment. Noninvasive brain stimulation and hyperbaric oxygen therapy showed promising results in the treatment of brain fog symptoms caused by long-COVID, with improved perfusion and cortical excitability. Furthermore, both rehabilitation strategies and PEA-LUT administration have been associated with improvements in symptoms of brain fog. Future studies should explore combinations of interventions and include longer follow-up periods to assess the long-term effects of these treatments. [ABSTRACT FROM AUTHOR]

Introduction: Despite its high lifetime prevalence rate and the elevated disability caused by posttraumatic stress disorder (PTSD), treatments exhibit modest efficacy. In consideration of the abnormal connectivity between the dorsolateral prefrontal cortex (DLPFC) and amygdala in PTSD, several randomized controlled trials (RCTs) addressing the efficacy of different noninvasive brain stimulation (NIBS) modalities for PTSD management have been undertaken. However, previous RCTs have reported inconsistent results. The current network meta‐analysis (NMA) aimed to compare the efficacy and acceptability of various NIBS protocols in PTSD management. Methods: We systematically searched ClinicalKey, Cochrane Central Register of Controlled Trials, Embase, ProQuest, PubMed, ScienceDirect, Web of Science, and ClinicalTrials.gov to identify relevant RCTs. The targeted RCTs was those comparing the efficacy of NIBS interventions, such as transcranial direct current stimulation (tDCS), repetitive transcranial magnetic stimulation (rTMS), and transcutaneous cervical vagal nerve stimulation, in patients with PTSD. The NMA was conducted using a frequentist model. The primary outcomes were changes in the overall severity of PTSD and acceptability (to be specific, rates of dropouts for any reason). Results: We identified 14 RCTs that enrolled 686 participants. The NMA demonstrated that among the investigated NIBS types, high‐frequency rTMS over bilateral DLPFCs was associated with the greatest reduction in overall PTSD severity. Further, in comparison with the sham controls, excitatory stimulation over the right DLPFC with/without excitatory stimulation over left DLPFC were associated with significant reductions in PTSD‐related symptoms, including depression and anxiety symptoms, and overall PTSD severity. Conclusions: This NMA demonstrated that excitatory stimulation over the right DLPFC with or without excitatory stimulation over left DLPFC were associated with significant reductions in PTSD‐related symptoms. Trial registration: PROSPERO CRD42023391562. [ABSTRACT FROM AUTHOR]

Over the past three decades, substantial advancements have occurred in non-invasive brain stimulation (NIBS). These developments encompass various non-invasive techniques aimed at modulating brain function. Among the most widely utilized methods today are transcranial magnetic stimulation (TMS) and transcranial electrical stimulation (TES), which include direct- or alternating-current transcranial stimulation (tDCS/tACS). In addition to these established techniques, newer modalities have emerged, broadening the scope of non-invasive neuromodulation approaches available for research and clinical applications in movement disorders, particularly for Parkinson's disease (PD) and, to a lesser extent, atypical Parkinsonism (AP). All NIBS techniques offer the opportunity to explore a wide range of neurophysiological mechanisms and exert influence over distinct brain regions implicated in the pathophysiology of Parkinsonism. This paper's first aim is to provide a brief overview of the historical background and underlying physiological principles of primary NIBS techniques, focusing on their translational relevance. It aims to shed light on the potential identification of biomarkers for diagnostic and therapeutic purposes, by summarising available experimental data on individuals with Parkinsonism. To date, despite promising findings indicating the potential utility of NIBS techniques in Parkinsonism, their integration into clinical routine for diagnostic or therapeutic protocols remains a subject of ongoing investigation and scientific debate. In this context, this paper addresses current unsolved issues and methodological challenges concerning the use of NIBS, focusing on the importance of future research endeavours for maximizing the efficacy and relevance of NIBS strategies for individuals with Parkinsonism. [ABSTRACT FROM AUTHOR]

Ischemic stroke is one of the leading causes of death and disability. As the currently used neurorehabilitation methods present several limitations, the ongoing research focuses on the use of non-invasive brain stimulation (NIBS) techniques such as transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS). NIBS methods were demonstrated to modulate neural excitability and improve motor and cognitive functioning in neurodegenerative diseases. However, their mechanisms of action are not fully elucidated, and the clinical outcomes are often unpredictable. This review explores the molecular processes underlying the effects of TMS and tDCS in stroke rehabilitation, including oxidative stress reduction, cell death, stimulation of neurogenesis, and neuroprotective phenotypes of glial cells. A highlight is put on the newly emerging therapeutic targets, such as ferroptotic and pyroptotic pathways. In addition, the issue of interindividual variability is discussed, and the role of neuroimaging techniques is investigated to get closer to personalized medicine. Furthermore, translational challenges of NIBS techniques are analyzed, and limitations of current clinical trials are investigated. The paper concludes with suggestions for further neurorehabilitation stroke treatment, putting the focus on combination and personalized therapies, as well as novel protocols of brain stimulation techniques. [ABSTRACT FROM AUTHOR]

The last decades have witnessed huge efforts devoted to deciphering the pathological mechanisms underlying Alzheimer's Disease (AD) and to testing new drugs, with the recent FDA approval of two anti-amyloid monoclonal antibodies for AD treatment. Beyond these drug-based experimentations, a number of pre-clinical and clinical trials are exploring the benefits of alternative treatments, such as non-invasive stimulation techniques on AD neuropathology and symptoms. Among the different non-invasive brain stimulation approaches, transcranial alternating current stimulation (tACS) is gaining particular attention due to its ability to externally control gamma oscillations. Here, we outline the current knowledge concerning the clinical efficacy, safety, ease-of-use and cost-effectiveness of tACS on early and advanced AD, applied specifically at 40 Hz frequency, and also summarise pre-clinical results on validated models of AD and ongoing patient-centred trials. [ABSTRACT FROM AUTHOR]

Background: Non-invasive brain stimulation (NIBS) combined with cognitive training (CT) may have shown some prospects on improving cognitive function in patients with Alzheimer's disease (AD) and mild cognitive impairment (MCI). However, data from clinical trials or meta-analysis involving NIBS combined with CT have shown controversial results. The aim of this systematic review and meta-analysis was to evaluate short-term and long-term effects of NIBS combined with CT on improving global cognition and other specific cognitive domains in patients with AD and MCI. Methods: This systematic review and meta-analysis was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Five electronic databases including PubMed, Web of Science, EBSCO, Cochrane Library and Embase were searched up from inception to 20 November 2023. The PEDro scale and the Cochrane's risk of bias assessment were used to evaluate risk of bias and methodological quality of included studies. All statistical analyses were conducted with Review Manager 5.3. Results: We included 15 studies with 685 patients. The PEDro scale was used to assess methodological quality with a mean score of 7.9. The results of meta-analysis showed that NIBS combined with CT was effective on improving global cognition in AD and MCI (SMD = 0.52, 95% CI (0.18, 0.87), p = 0.003), especially for patients accepting repetitive transcranial magnetic stimulation (rTMS) combined with CT (SMD = 0.46, 95% CI (0.14, 0.78), p = 0.005). AD could achieve global cognition improvement from NIBS combined with CT group (SMD = 0.77, 95% CI (0.19, 1.35), p = 0.01). Transcranial direct current stimulation (tDCS) combined with CT could improve language function in AD and MCI (SMD = 0.29, 95% CI (0.03, 0.55), p = 0.03). At evaluation follow-up, rTMS combined with CT exhibited larger therapeutic responses to AD and MCI in global cognition (SMD = 0.55, 95% CI (0.09, 1.02), p = 0.02). AD could achieve global cognition (SMD = 0.40, 95% CI (0.03, 0.77), p = 0.03) and attention/working memory (SMD = 0.72, 95% CI (0.23, 1.20), p = 0.004) improvement after evaluation follow-up from NIBS combined with CT group. Conclusions: Overall, NIBS combined with CT, particularly rTMS combined with CT, has both short-term and follow-up effects on improving global cognition, mainly in patients with AD. tDCS combined with CT has advantages on improving language function in AD and MCI. Future more studies need evaluate cognitive effects of NIBS combined with CT on other specific cognitive domain in patients with cognitive deterioration. [ABSTRACT FROM AUTHOR]

The neural mechanisms underlying language recovery after a stroke remain controversial. This review aimed to summarize the plasticity and reorganization mechanisms of the language network through neuroimaging studies. Initially, we discussed the involvement of right language homologues, perilesional tissue, and domain-general networks. Subsequently, we summarized the white matter functional mapping and remodeling mechanisms associated with language subskills. Finally, we explored how non-invasive brain stimulation (NIBS) promoted language recovery by inducing neural network plasticity. It was observed that the recruitment of right hemisphere language area homologues played a pivotal role in the early stages of frontal post-stroke aphasia (PSA), particularly in patients with larger lesions. Perilesional plasticity correlated with improved speech performance and prognosis. The domain-general networks could respond to increased "effort" in a task-dependent manner from the top-down when the downstream language network was impaired. Fluency, repetition, comprehension, naming, and reading skills exhibited overlapping and unique dual-pathway functional mapping models. In the acute phase, the structural remodeling of white matter tracts became challenging, with recovery predominantly dependent on cortical activation. Similar to the pattern of cortical activation, during the subacute and chronic phases, improvements in language functions depended, respectively, on the remodeling of right white matter tracts and the restoration of left-lateralized language structural network patterns. Moreover, the midline superior frontal gyrus/dorsal anterior cingulate cortex emerged as a promising target for NIBS. These findings offered theoretical insights for the early personalized treatment of aphasia after stroke. [ABSTRACT FROM AUTHOR]

Research on the benefits of non-invasive brain stimulation in stroke patients to improve executive functions is scarce. The objective of this study was to investigate the effectiveness of transcranial direct current stimulation (tDCS) in combination with cognitive training for the rehabilitation of executive functions in acute and subacute stroke patients as well as to explore the underlying physiological mechanisms. A triple-blinded, randomized-controlled clinical trial will be conducted involving 60 stroke patients with frontal or basal ganglia lesions and a Montreal Cognitive Assessment (MoCA) score less than 26. Participants will be randomly assigned to receive active tDCS (anode over the left dorsolateral prefrontal cortex, cathode at the right supraorbital region, 20 min at 2 mA) or sham tDCS in a 1:1 ratio for 10 sessions, followed by targeted executive function training. The primary efficacy outcome will be the MoCA score, while secondary outcomes will include the five-digit test (inhibitory control), the Digit Span Task (working memory), the abbreviated version of the Wisconsin Card Sorting test (cognitive flexibility), modified Rankin scale (functional state), Beck-II depression inventory, apathy evaluation scale, and the WHOQOL-BREF (quality of life), assessed immediately after the intervention and at 1, 3, 6, and 12 months post-intervention. Additionally, resting-state functional connectivity and blood biomarkers, such as neurotrophins, growth factors, and inflammatory molecules, will be evaluated before and after the intervention. This study will contribute to the investigation of the efficacy of tDCS in rehabilitating executive functions in acute and subacute stroke patients. The multidimensional approach utilized in this study, which includes analysis of resting-state connectivity and neuroplasticity-related blood biomarkers, is expected to provide insights into the underlying brain mechanisms involved in the rehabilitation of dysexecutive syndrome. [ABSTRACT FROM AUTHOR]

Non-invasive brain stimulation (NIBS) approaches have seen a rise in utilization in both clinical and basic neuroscience in recent years. Here, we concentrate on the two methods that have received the greatest research: transcranial direct current stimulation (tDCS) and repetitive transcranial magnetic stimulation (rTMS). Both approaches have yielded pertinent data regarding the cortical excitability in subjects in good health as well as pertinent advancements in the management of various clinical disorders. NIBS is a helpful method for comprehending the cortical control of the ANS. Previous research has shown that there are notable changes in muscular sympathetic nerve activity when the motor cortex is modulated. Furthermore, in NIBS investigations, the ANS has been employed more frequently as an outcome measure to comprehend the overall impacts of these methods, including their safety profile. Though there is ample proof that brain stimulation has autonomic effects on animals, new research on the connection between NIBS and the ANS has produced contradictory findings. In order to better understand NIBS processes and ANS function, it is crucial to take into account the reciprocal relationship that exists between central modulation and ANS function. [ABSTRACT FROM AUTHOR]

In recent decades, numerous studies have investigated the effects of transcranial direct current stimulation (tDCS) on cognitive functioning. However, results of these studies frequently display inconsistency and pose challenges regarding replicability. The present work aimed at testing the hypothesis of mood as potential moderator of prefrontal tDCS effects on executive functions (EF). This hypothesis refers to the relationship between mood and EF, as well as to the association of mood with the dorsolateral prefrontal cortex (dlPFC) activity. We conducted a meta-analysis of 11 articles where the dlPFC was stimulated with anodal tDCS, EF were measured, and mood was assessed prior to the stimulation. We then conducted a meta-regression to examine whether mood moderated the tDCS effects on EF. While no significant effect of tDCS on EF emerged from the meta-analysis, the meta-regression indicated that mood plays a significant role as moderator, with greater tDCS effects on EF in individuals with higher depressive symptoms. The limited number of studies included, the heterogeneous samples considered, and the limited generalizability to other non-invasive brain stimulation techniques and affective states. Findings suggest that evaluating mood prior to stimulation could increase the sensitivity and specificity of tDCS application, and provide the first meta-analytic evidence in favor of the affective state-dependency hypothesis. • The effect of prefrontal tDCS on executive functions was significantly moderated by mood. • Individuals with higher depressive symptoms experienced greater benefits from tDCS application. • Evidence supporting the affective state-dependency hypothesis has been provided. [ABSTRACT FROM AUTHOR]

Background: Neuropsychiatric disorders significantly burden individuals and society, necessitating the exploration of innovative treatment approaches. Non-invasive brain stimulation techniques have emerged as promising interventions for these disorders, offering potential therapeutic benefits with minimal side effects. This narrative review provides a comprehensive overview of non-invasive brain stimulation techniques' current applications and future directions in managing neuropsychiatric disorders. Methods: A thorough search of relevant literature was conducted to identify studies investigating non-invasive brain stimulation techniques in neuropsychiatric disorders. The selected studies were critically reviewed, and their findings were synthesised to provide a comprehensive overview of the current state of knowledge in the field. Results: The review highlights the current applications of non-invasive brain stimulation techniques in neuropsychiatric disorders, including major depressive disorder, Parkinson's disease, schizophrenia, insomnia, and cognitive impairments. It presents evidence supporting the efficacy of these techniques in modulating brain activity, alleviating symptoms, and enhancing cognitive functions. Furthermore, the review addresses challenges such as interindividual variability, optimal target site selection, and standardisation of protocols. It also discusses potential future directions, including exploring novel target sites, personalised stimulation protocols, integrating with other treatment modalities, and identifying biomarkers for treatment response. Conclusion: Non-invasive brain stimulation techniques offer promising avenues for managing neuropsychiatric disorders. Further research is necessary to optimise stimulation protocols, establish standardised guidelines, and identify biomarkers for treatment response. The findings underscore the potential of non-invasive brain stimulation techniques as valuable additions to the armamentarium of neuropsychiatric treatments. [ABSTRACT FROM AUTHOR]