Dysphagia after stroke: research advances in treatment interventions.

After a stroke, most patients have dysphagia, which can lead to aspiration pneumonia, malnutrition, and adverse functional outcomes. Protective interventions aimed at reducing these complications remain the cornerstone of treatment. Dietary adjustments and oral hygiene help mitigate the risk of aspiration pneumonia, and nutritional supplementation, including tube feeding, might be needed to prevent malnutrition. Rehabilitative interventions aim to enhance swallowing function, with different behavioural strategies showing promise in small studies. Investigations have explored the use of pharmaceutical agents such as capsaicin and other Transient-Receptor-Potential-Vanilloid-1 (TRPV-1) sensory receptor agonists, which alter sensory perception in the pharynx. Neurostimulation techniques, such as transcranial direct current stimulation, repetitive transcranial magnetic stimulation, and pharyngeal electrical stimulation, might promote neuroplasticity within the sensorimotor swallowing network. Further advancements in the understanding of central and peripheral sensorimotor mechanisms in patients with dysphagia after a stroke, and during their recovery, will contribute to optimising treatment protocols.

Transcranial alternating current stimulation improves quality of life in Parkinson's disease: study protocol for a randomized, double-blind, controlled trial.

BACKGROUND: The neural cells in the brains of patients with Parkinson's disease (PWP) display aberrant synchronized oscillatory activity within the beta frequency range. Additionally, enhanced gamma oscillations may serve as a compensatory mechanism for motor inhibition mediated by beta activity and also reinstate plasticity in the primary motor cortex affected by Parkinson's disease. Transcranial alternating current stimulation (tACS) can synchronize endogenous oscillations with exogenous rhythms, thereby modulating cortical activity. The objective of this study is to investigate whether the addition of tACS to multidisciplinary intensive rehabilitation treatment (MIRT) can improve symptoms of PWP so as to enhance the quality of life in individuals with Parkinson's disease based on the central-peripheral-central theory. METHODS: The present study was a randomized, double-blind trial that enrolled 60 individuals with Parkinson's disease aged between 45 and 70 years, who had Hoehn-Yahr scale scores ranging from 1 to 3. Participants were randomly assigned in a 1:1 ratio to either the tACS + MIRT group or the sham-tACS + MIRT group. The trial consisted of a two-week double-blind treatment period followed by a 24-week follow-up period, resulting in a total duration of twenty-six weeks. The primary outcome measured the change in PDQ-39 scores from baseline (T0) to 4 weeks (T2), 12 weeks (T3), and 24 weeks (T4) after completion of the intervention. The secondary outcome assessed changes in MDS-UPDRS III scores at T0, the end of intervention (T1), T2, T3, and T4. Additional clinical assessments and mechanistic studies were conducted as tertiary outcomes. DISCUSSION: The objective of this study is to demonstrate that tACS can enhance overall functionality and improve quality of life in PWP, based on the framework of MIRT. Additionally, it seeks to establish a potential correlation between these therapeutic effects and neuroplasticity alterations in relevant brain regions. The efficacy of tACS will be assessed during the follow-up period in order to optimize neuroplasticity and enhance its potential impact on rehabilitation efficiency for PWP. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2300071969. Registered on 30 May 2023.

Safety, tolerability and blinding efficiency of non-invasive deep transcranial temporal interference stimulation: first experience from more than 250 sessions.

Objective. Selective neuromodulation of deep brain regions has for a long time only been possible through invasive approaches, because of the steep depth-focality trade-off of conventional non-invasive brain stimulation (NIBS) techniques.Approach. An approach that has recently emerged for deep NIBS in humans is transcranial Temporal Interference Stimulation (tTIS). However, a crucial aspect for its potential wide use is to ensure that it is tolerable, compatible with efficient blinding and safe.Main results. Here, we show the favorable tolerability and safety profiles and the robust blinding efficiency of deep tTIS targeting the striatum or hippocampus by leveraging a large dataset (119 participants, 257 sessions), including young and older adults and patients with traumatic brain injury. tTIS-evoked sensations were generally rated as 'mild', were equivalent in active and placebo tTIS conditions and did not enable participants to discern stimulation type.Significance. Overall, tTIS emerges as a promising tool for deep NIBS for robust double-blind, placebo-controlled designs.

Safety of noninvasive brain stimulation in children.

PURPOSE OF REVIEW: Noninvasive brain stimulation (NIBS) is a promising method for altering cortical excitability with clinical implications. It has been increasingly used in children, especially in neurodevelopmental disorders. Yet, its safety and applications in the developing brain require further investigation. This review aims to provide an overview of the safety of commonly used NIBS techniques in children, including transcranial electrical stimulation (tES) and transcranial magnetic stimulation (TMS). Safety data for other NIBS methods is not reported in this review. RECENT FINDINGS: In line with studies from the last decade, findings in the last 2 years (2022-2023) support the safety of NIBS in children and adolescents within the currently applied protocols. Both tES and TMS are well tolerated, if safety rules, including exclusion criteria, are applied. SUMMARY: We briefly discussed developmental aspects of stimulation parameters that need to be considered in the developing brain and provided an up-to-date overview of tES/TMS applications in children and adolescents. Overall, the safety profile of tES/TMS in children is good. For both the tES and TMS applications, epilepsy and active seizure disorder should be exclusion criteria to prevent potential seizures. Using child-sized earplugs is required for TMS applications. We lack large randomized double-blind trialsand longitudinal studies to establish the safety of NIBS in children. VIDEO ABSTRACT: http://links.lww.com/YCO/A78 .

Effectiveness and brain mechanism of multi-target transcranial alternating current stimulation (tACS) on motor learning in stroke patients: study protocol for a randomized controlled trial.

BACKGROUND: Transcranial alternating current stimulation (tACS) has proven to be an effective treatment for improving cognition, a crucial factor in motor learning. However, current studies are predominantly focused on the motor cortex, and the potential brain mechanisms responsible for the therapeutic effects are still unclear. Given the interconnected nature of motor learning within the brain network, we have proposed a novel approach known as multi-target tACS. This study aims to ascertain whether multi-target tACS is more effective than single-target stimulation in stroke patients and to further explore the potential underlying brain mechanisms by using techniques such as transcranial magnetic stimulation (TMS) and magnetic resonance imaging (MRI). METHODS: This study employs a double-blind, sham-controlled, randomized controlled trial design with a 2-week intervention period. Both participants and outcome assessors will remain unaware of treatment allocation throughout the study. Thirty-nine stroke patients will be recruited and randomized into three distinct groups, including the sham tACS group (SS group), the single-target tACS group (ST group), and the multi-target tACS group (MT group), at a 1:1:1 ratio. The primary outcomes are series reaction time tests (SRTTs) combined with electroencephalograms (EEGs). The secondary outcomes include motor evoked potential (MEP), central motor conduction time (CMCT), short interval intracortical inhibition (SICI), intracortical facilitation (ICF), magnetic resonance imaging (MRI), Box and Block Test (BBT), and blood sample RNA sequencing. The tACS interventions for all three groups will be administered over a 2-week period, with outcome assessments conducted at baseline (T0) and 1 day (T1), 7 days (T2), and 14 days (T3) of the intervention phase. DISCUSSION: The study's findings will determine the potential of 40-Hz tACS to improve motor learning in stroke patients. Additionally, it will compare the effectiveness of multi-target and single-target approaches, shedding light on their respective improvement effects. Through the utilization of techniques such as TMS and MRI, the study aims to uncover the underlying brain mechanisms responsible for the therapeutic impact. Furthermore, the intervention has the potential to facilitate motor learning efficiency, thereby contributing to the advancement of future stroke rehabilitation treatment. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2300073465. Registered on 11 July 2023.

Safety of ipsilesional anodal transcranial direct current stimulation in acute photothrombotic stroke: implications for early neurorehabilitation.

Early rehabilitation in the acute phase of stroke, that bears unique neuroplastic properties, is the current standard to reduce disability. Anodal transcranial direct current stimulation can augment neurorehabilitation in chronic stroke. Studies in the acute phase are sparse and held back by inconclusive preclinical data pointing towards potential negative interaction of the excitability increasing tDCS modality with stroke-induced glutamate toxicity. In this present study, we aimed to evaluate structural and behavioral safety of anodal tDCS applied in the acute phase of stroke. Photothrombotic stroke including the right primary motor cortex was induced in rats. 24 h after stroke anodal tDCS was applied for 20 min ipsilesionally at one of four different current densities in freely moving animals. Effects on the infarct volume and on stroke induced neuroinflammation were assessed. Behavioral consequences were monitored. Infarct volume and the modified Neurological Severity Score were not affected by anodal tDCS. Pasta handling, a more sensitive task for sensorimotor deficits, and microglia reactivity indicated potentially harmful effects at the highest tDCS current density tested (47.8 A/m2), which is more than 60 times higher than intensities commonly used in humans. Compared to published safety limits of anodal tDCS in healthy rats, recent stroke does not increase the sensitivity of the brain to anodal tDCS, as assessed by lesion size and neuroinflammatory response. Behavioral deficits only occurred at the highest intensity, which was associated with increased neuroinflammation. When safety limits of commonly used clinical tDCS are met, augmentation of early neurorehabilitation after stroke by anodal tDCS appears to be feasible.

Adjunctive duration-doubled transcranial direct current stimulation for the treatment of depressive patients with suicidal ideation: study protocol for a double-blind, randomized, sham-controlled trial.

BACKGROUND: The problem of suicide has become increasingly common in individuals with major depressive disorder (MDD). Transcranial direct current stimulation (tDCS) is an effective treatment for MDD with 2 milliamperes (mA) for at least 30 min per day for 2 weeks. This study aims to investigate the efficacy of daily duration-doubled tDCS as an adjunctive intervention for rapidly reducing suicidal ideation and improving depression in MDD patients. METHODS: In this double-blind, randomized, sham-controlled study, 76 MDD patients with suicidal ideation are randomly assigned to either active (n=38) or sham (n=38) tDCS group. The anode and cathode are placed over the scalp areas corresponding to left and right dorsolateral prefrontal cortex (DLPFC), respectively, and each stimulation lasts for 60 min. The primary outcome is defined as change of Beck Scale for Suicide Ideation (BSI) after 5 and 10 sessions. The change of other clinical assessments, blood biomarkers related to suicidal ideation and depressive sumptoms are defined as secondary outcomes. Blood biomarkers related to suicidal ideation are collected at baseline and after 10 sessions. DISCUSSION: This study suggests the adjunctive duration-doubled tDCS might be a novel method to rapidly reduce suicidal ideation and improve depressive symptom. The variation of biomarkers could be potential predictive models of suicide risk. TRIAL REGISTRATION: The trial protocol is registered with ClinicalTrials.gov under protocol registration number NCT05555927. Registered on September 25, 2022.

Somatosensory evoked potentials amplitude is enhanced after non-invasive brain stimulation in chronic ischemic stroke: Preliminary results from a randomised control trial.

OBJECTIVE: To investigate the effects of transcranial electrical and magnetic non-invasive brain stimulation (NIBS) protocols on somatosensory evoked potential (SEP) in chronic ischemic stroke. METHODS: 33 patients were randomly assigned to one of the four treatment groups of the transcranial direct current stimulation (tDCS) and/or repetitive transcranial magnetic stimulation (rTMS) protocol. SEP parameters were recorded before and after ten days of the treatment session. All the statistical analyses were carried out using SPSS version 19. RESULTS: It was found that there is a statistically significant improvement in the N20-P22 mean amplitude after treatment sessions in all groups except the group where tDCS and rTMS groups were sham. On paired t-tests, the difference betweeen post and pre-stimulation SEP amplitudes for the real tDCS and real rTMS coupled group was 1.045 ± 0.732 (p value = 0.005). For sham tDCS+real rTMS group, 1.05 ± 0.96 (P = 0.04); for real tDCS+sham rTMS 0.543 ± 0.332 (P = 0.01) and for double sham stimulation, 0.204 ± 0.648 (P =  0.4) respectively CONCLUSION: In ischemic stroke patients, either or coupled true transcranial tDCS and rTMS was found to be safe and significantly enhanced the amplitude of cortical somatosensory potentials when combined with standard physiotherapy, in the interim analysis of an ongoing randomised controlled trial. CLINICAL TRIAL REGISTRY OF INDIA: CTRI/2019/11/022009 SIGNIFICANCE: The results of this research indicates the importance of RCTs in developing robust improved NIBS protocols coupled to physiotherapy to enhance the sensory-motor functional recovery following ischemic stroke.

Transcranial Direct Current Stimulation for Knee Osteoarthritis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

OBJECTIVE: The effects of transcranial direct current stimulation (tDCS) in the treatment of knee osteoarthritis (KOA) is still unclear. The objective is to evaluate the efficacy and safety of tDCS in improving symptoms in patients with KOA. METHODS: The following electronic databases were searched for eligible randomized controlled trials (RCTs): PubMed, Embase, Web of Science, and the Cochrane Library. The search was performed from the inception dates to April 30, 2023. Data extraction and quality assessment were performed by two independent reviewers. Standard mean differences (SMDs) with 95% confidence intervals (95% CIs) for pooled data were calculated. A random-effects model was used for the data analyses. The primary outcomes were pain and physical function. Secondary outcomes included stiffness, mobility performance, quality of life, pressure pain tolerance, and plasma levels of brain-derived neurotrophic factor (BDNF). RESULTS: This meta-analysis included 13 RCTs. tDCS was significantly associated with pain decrease compared with sham tDCS (SMD = -0.62, 95% CI -0.87 to -0.37, P < 0.00001). When comparing tDCS plus other non-tDCS with sham tDCS plus other non-tDCS, there was no longer a significant association with pain decrease (SMD = -0.45, 95% CI -1.08 to 0.17, P = 0.16). The changes in physical function were not significantly different between the tDCS and sham tDCS groups (SMD = -0.09, 95% CI -0.56 to 0.38, P = 0.71). When comparing tDCS plus other non-tDCS with sham tDCS plus other non-tDCS, there was still no significant association with improvement in physical function (SMD = -0.66, 95% CI -1.63 to 0.30, P = 0.18). There was no significant difference with improvement in stiffness (SMD = -0.21, 95% CI -0.77 to 0.34, P = 0.45), mobility performance (SMD = 4.58, 95% CI -9.21 to 18.37, P = 0.51), quality of life (SMD = -7.01, 95% CI -22.61 to 8.59, P = 0.38), and pressure pain tolerance (SMD = 0.30, 95% CI -0.09 to 0.69, P = 0.13). There was a statistically significant reduction in plasma levels of BDNF (SMD = -13.57, 95% CI -24.23 to -2.92, P = 0.01). CONCLUSION: In conclusion, tDCS could significantly alleviate pain, but it might have no efficacy in physical function, stiffness, mobility performance, quality of life, and pressure pain tolerance among patients with KOA.

Transcranial direct current stimulation for fatigue in neurological conditions: A systematic scoping review.

BACKGROUND AND PURPOSE: Fatigue following neurological conditions negatively impacts daily activities, reducing overall quality of life. Transcranial direct current stimulation (tDCS) for fatigue management is still underexplored. This scoping review explores its use in managing fatigue among various neurological conditions. METHODS: A thorough literature search was carried out using PubMed, Scopus, CINAHL, Web of Science, Embase, ProQuest, and the Cochrane Library. Google Scholar and clinicaltrials.gov were manually searched for gray literature and ongoing trials, respectively. Regardless of the study design, all studies utilizing tDCS for the management of fatigue in various neurological conditions were considered. Two reviewers independently screened all the studies, following which the data were retrieved. RESULTS: Studies employing tDCS for fatigue management across neurological conditions is as follows: Multiple sclerosis (MS) (n = 28, 66%), stroke (n = 5, 12%), Parkinson's disease (PD) (n = 4, 10%), post-polio syndrome (PPS) (n = 2, 5%), traumatic brain injury (TBI) (n = 2, 5%), and amyotrophic lateral sclerosis (n = 1, 2%). All the studies used anodal stimulation, with the common stimulation site being the left dorsolateral prefrontal cortex for MS, stroke, and PD. A stimulation intensity of 1.0-4.0 mA with a duration ranging from 15 to 30 min in 1 to 24 sessions were commonly reported. The Fatigue Severity Scale (n = 21) and Modified Fatigue Impact Scale (n = 17) were frequently implemented outcome measures. Regardless of the study design, 36/42 (85.7%) studies reported an improvement in fatigue scores in the tDCS group. The common adverse events noted were tingling (n = 8, 35%), headache (n = 6, 26%), and itching (n = 6, 26%). DISCUSSION: Application of tDCS for fatigue was explored in individuals with stroke, PD, PPS, and TBI after MS. Even though a wide range of treatment parameters and outcome measures were adopted to assess and target fatigue, tDCS proves to have a promising role in alleviating this symptom.

Neuroplasticity in levodopa-induced dyskinesias: An overview on pathophysiology and therapeutic targets.

Levodopa-induced dyskinesias (LIDs) are a common complication in patients with Parkinson's disease (PD). A complex cascade of electrophysiological and molecular events that induce aberrant plasticity in the cortico-basal ganglia system plays a key role in the pathophysiology of LIDs. In the striatum, multiple neurotransmitters regulate the different forms of physiological synaptic plasticity to provide it in a bidirectional and Hebbian manner. In PD, impairment of both long-term potentiation (LTP) and long-term depression (LTD) progresses with disease and dopaminergic denervation of striatum. The altered balance between LTP and LTD processes leads to unidirectional changes in plasticity that cause network dysregulation and the development of involuntary movements. These alterations have been documented, in both experimental models and PD patients, not only in deep brain structures but also at motor cortex. Invasive and non-invasive neuromodulation treatments, as deep brain stimulation, transcranial magnetic stimulation, or transcranial direct current stimulation, may provide strategies to modulate the aberrant plasticity in the cortico-basal ganglia network of patients affected by LIDs, thus restoring normal neurophysiological functioning and treating dyskinesias. In this review, we discuss the evidence for neuroplasticity impairment in experimental PD models and in patients affected by LIDs, and potential neuromodulation strategies that may modulate aberrant plasticity.

Motor cortex transcranial direct current stimulation improves non-motor symptoms in early-onset Parkinson's disease: a pilot study.

Early-onset Parkinson's Disease (EOPD) demands tailored treatments. The younger age of patients might account for a higher sensitivity to transcranial direct current stimulation (tDCS) based non-invasive neuromodulation, which may raise as an integrative therapy in the field. Accordingly, here we assessed the safety and efficacy of the primary left motor cortex (M1) anodal tDCS in EOPD. Ten idiopathic EOPD patients received tDCS at 2.0 mA per 20 min for 10 days within a crossover, double-blind, sham-controlled pilot study. The outcome was evaluated by measuring changes in MDS-UPDRS part III, Non-Motor Symptoms Scale (NMSS), PD-cognitive rating scale, and PD Quality of Life Questionnaire-39 scores. We showed that anodal but not sham tDCS significantly reduced the NMSS total and "item 2" (sleep/fatigue) scores. Other parameters were not modified. No adverse events occurred. M1 anodal tDCS might thus evoke plasticity changes in cortical-subcortical circuits involved in non-motor functions, supporting the value as a therapeutic option in EOPD.

Efficacy and safety of non-invasive brain stimulation on cognitive function for cognitive impairment associated with schizophrenia: A systematic review and meta-analysis.

Based on existing evidence of the effects of the most commonly used non-invasive brain stimulation (NIBS), which includes transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), we conducted a meta-analysis to investigate the cognitive improvement and safety of NIBS on schizophrenia-related cognitive impairment. PubMed, EMBASE, Cochrane Library, and Web of Science were searched. The Cochrane Risk of Bias tool was used to assess the risk of bias of the included RCTs; Review Manager, version 5.4.1, was used to perform the statistical analysis. Twenty double-blind, randomized, sham-controlled trials involving 997 patients were included. As a result, no significant improvement in cognitive function was observed after NIBS treatment. However, the overall treatment effect of the two main NIBS modes (i.e., rTMS and tDCS) was associated with significantly larger improvements in negative symptoms and good tolerability in patients with schizophrenia compared to sham-controls (SMD = -0.56, 95% CI [-1.03, -0.08], p = 0.02, I2 = 88%). NIBS model and stimulus parameters influenced the effect of NIBS. More favorable effects were observed in patients who received rTMS stimulation (SMD = 0.25, 95% CI [0.01, 0.49], p = 0.04, I2 = 0%) in the left dorsolateral prefrontal cortex with a stimulation intensity of 20 Hz (p = 0.004) for a period longer than 1 month (p < 0.05). Yet, due to the limited number of included studies and heterogeneity in both study design and target population, the results of this analysis need to be interpreted with caution.

Exploring sensory, motor, and pain responses as potential side or therapeutic effects of sub-2 mA, 400 Hz transcranial pulsed current stimulation.

BACKGROUND: Various brain stimulation devices capable of generating high-frequency currents are readily available. However, our comprehension of the potential side or therapeutic effects associated with high-frequency transcranial pulsed current stimulation (tPCS), particularly concerning the new 400 Hz tPCS device, AscenZ-IV Stimulator, developed by AscenZion Neuromodulation Co. Pte. Ltd. in Singapore, remains incomplete. OBJECTIVE: This study examines preliminary parameters for the safe and comfortable application of 400 Hz tPCS at intensities below 2 mA. METHODS: In a cross-sectional study, 45 healthy participants underwent sub-2 mA 400 Hz tPCS to assess sensory, motor, and pain thresholds on the dominant side. Study 1 (N = 15) targeted the primary motor cortex of the right-hand area, while study 2 (N = 30) focused on the back of the right forearm. RESULTS: Study one showed that increasing the current intensity gradually resulted in no responses at sub-0.3 mA levels, but higher intensities (p < 0.001) induced sensory perception and pain responses. Study two replicated these findings and additionally induced motor responses along with the sensory and pain responses. CONCLUSION: Despite the theoretical classification of tPCS as a subsensory level of stimulation, and the expectation that individuals receiving this type of current should not typically feel its application on the body, this high-frequency tPCS device generates different levels of stimulation due to the physiological phenomenon known as temporal summation. These novel levels of stimulation could be viewed as either potential "side-effects" of high frequency tPCS or as additional "therapeutic benefits". This dual capacity may position the device as one that generates both neuromodulatory and neurostimulatory currents. Comprehensive comprehension of this is vital for the development of therapeutic protocols that incorporate high-frequency tPCS.

Tolerability and blinding of high-definition transcranial direct current stimulation among older adults at intensities of up to 4 mA per electrode.

BACKGROUND: Few studies have investigated tolerability, blinding, and double-blinding of High-Definition transcranial Direct Current Stimulation (HD-tDCS) at amplitudes above 2 milliamps (mA). OBJECTIVE: We examined a) tolerability of HD-tDCS during stimulation sessions and b) blinding and double blinding of participants and study team members. METHODS: Data from a mixed neurologic sample of 292 older adults were pooled from 3046 HD-tDCS sessions (2329 active; 717 sham). Per electrode amplitudes ranged from 1 mA to 4 mA with total currents up to 10 mA. Participants completed a standardized sensation (tolerability) questionnaire after each session. Participants and study team members stated whether the participant received active or sham stimulation at the end of various sessions. Data were collapsed into the presence/absence of a symptom due to low rates of positive responding and were analyzed for both differences and bioequivalency. RESULTS: There were no safety-related adverse events. HD-tDCS was well tolerated with mostly no ("none") or "mild" sensations reported across sessions, regardless of active or sham condition and in both stimulation naïve and experienced participants. There were no significant differences in side effects between active and sham, with some achieving bioequivalence. Tingling and itching were significantly more common after lower (<2 mA) than higher (≥3 mA) amplitude active sessions, while skin redness was significantly more common after higher amplitudes. Blinding was effective at the participant and study team levels. CONCLUSIONS: HD-tDCS was well tolerated with center electrode amplitudes up to 4 mA. The bimodal ramp-up/down format of the sham was effective for blinding. These results support higher scalp-based amplitudes that enable greater brain-based current intensities in older adults.

Efficacy and safety of Transcranial Direct Current Stimulation (tDCS) on cognitive function in chronic schizophrenia with Tardive Dyskinesia (TD): a randomized, double-blind, sham-controlled, clinical trial.

OBJECTIVE: Previous studies have shown that transcranial direct current stimulation(tDCS) led to an improvement of cognitive function in patients with schizophrenia, but rare study has explored the effect of tDCS on long-term hospitalized chronic schizophrenia with tardive dyskinesia (TD). The present research explored if cognitive function in patients with long-term hospitalized chronic schizophrenia with TD could be improved through tDCS. METHODS: This study is a randomized, double-blind, sham-controlled clinical trial. Of the 52 patients, 14 dropped out, and 38 completed the experiment. Thirty-eight patients on stable treatment regimens were randomly assigned to receive active tDCS(n = 21) or sham stimulation(n = 17) on weekdays of the first, third, and fifth weeks of treatment. Patients performed the Pattern Recognition Memory (PRM) and the Intra/Extradimensional Set Shift (IED) from the Cambridge Neuropsychological Test Automated Battery (CANTAB) at baseline and the end of week 3, week 5. Clinical symptoms were also measured at the baseline and the fifth week using the Scale for the Assessment of Negative Symptoms (SANS) and the Positive and Negative Syndrome Scale (PANSS). Side effects of tDCS were assessed with an experimenter-administered open-ended questionnaire during the whole experiment. RESULTS: There were no significant differences in PRM and IED performance metrics, SANS total score and PANSS total score between active and sham tDCS groups at the end of week 5 (p > 0.05). Furthermore, there was a significant difference in the adverse effects of the tingling sensation between the two groups (p < 0.05), but there was no significant difference in other side effects (p > 0.05). CONCLUSION: According to these findings, no evidence supports using anodal stimulation over the left dorsolateral prefrontal cortex to improve cognitive function in patients with long-term hospitalized chronic schizophrenia with TD.

Transcranial random noise stimulation combined with cognitive training for treating ADHD: a randomized, sham-controlled clinical trial.

Non-invasive brain stimulation has been suggested as a potential treatment for improving symptomology and cognitive deficits in Attention-Deficit/Hyperactivity Disorder (ADHD), the most common childhood neurodevelopmental disorder. Here, we examined whether a novel form of stimulation, high-frequency transcranial random noise stimulation (tRNS), applied with cognitive training (CT), may impact symptoms and neural oscillations in children with ADHD. We conducted a randomized, double-blind, sham-controlled trial in 23 unmedicated children with ADHD, who received either tRNS over the right inferior frontal gyrus (rIFG) and left dorsolateral prefrontal cortex (lDLPFC) or sham stimulation for 2 weeks, combined with CT. tRNS + CT yielded significant clinical improvements (reduced parent-reported ADHD rating-scale scores) following treatment, compared to the control intervention. These improvements did not change significantly at a 3-week follow-up. Moreover, resting state (RS)-EEG periodic beta bandwidth of the extracted peaks was reduced in the experimental compared to control group immediately following treatment, with further reduction at follow-up. A lower aperiodic exponent, which reflects a higher cortical excitation/inhibition (E/I) balance and has been related to cognitive improvement, was seen in the experimental compared to control group. This replicates previous tRNS findings in adults without ADHD but was significant only when using a directional hypothesis. The experimental group further exhibited longer sleep onset latencies and more wake-up times following treatment compared to the control group. No significant group differences were seen in executive functions, nor in reported adverse events. We conclude that tRNS + CT has a lasting clinical effect on ADHD symptoms and on beta activity. These results provide a preliminary direction towards a novel intervention in pediatric ADHD.

Efficacy and safety of noninvasive brain stimulation for patients with cerebellar ataxia: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: With the development of noninvasive brain stimulation (NIBS) techniques, many researchers have turned their attention to NIBS as a promising treatment for cerebellar ataxia. Therefore, we conducted a systematic review and meta-analysis to investigate the efficacy and safety of NIBS in treating patients with cerebellar ataxia. METHODS: Databases, including PubMed, Embase, Web of Science, Medline, and Cochrane Library, were retrieved for relevant randomized controlled trials (RCTs). Two researchers conducted literature screening, data extraction, literature quality assessment, and heterogeneity analysis between RCTs. According to the magnitude of heterogeneity I2, an appropriate data analysis model was selected for meta-analysis. RESULTS: A total of 14 RCTs including 406 patients with cerebellar ataxia met the inclusion criteria. The included RCTs had an overall low-risk bias and an intermediate level of evidence recommendation for key outcome indicators, such as the scale for the assessment and rating of ataxia (SARA) and international cooperative ataxia rating scale (ICARS). The results of meta-analysis showed that cerebellar NIBS, including transcranial direct current stimulation (tDCS) and repetitive transcranial magnetic stimulation (rTMS), was effective in reducing the SARA scores (MD = - 3.45, 95%CI = [- 4.85, - 2.50], P < 0.05) and ICARS scores (MD = - 10.87, 95%CI = [- 14.46, - 7.28], P < 0.05) in patients with cerebellar ataxia compared to controls. Subgroup analysis showed that the efficacy of tDCS and rTMS was statistically different in patients with cerebellar ataxia as assessed by the SARA scores, but not by the ICARS scores. There was statistically significant difference in the efficacy of NIBS for the treatment of cerebellar ataxia caused by different etiologies. As for safety, 8 of 14 included studies documented the adverse effects of NIBS, and only two studies reported the mild adverse events of NIBS. CONCLUSIONS: Cerebellar NIBS was safe and effective in improving the motor coordination of patients with cerebellar ataxia, and tDCS was better than rTMS in the treatment of cerebellar ataxia. In addition, the efficacy of NIBS was different in the treatment of different types of cerebellar ataxia.