Transcranial Direct Current Stimulation Research Articles

Adjunctive High-Definition Transcranial Direct Current Stimulation in Treatment of Resistant Auditory Verbal Hallucinations in Schizophrenia: A Randomized Sham-Controlled Trial.

Resistant auditory verbal hallucination (AVH) remains a disabling symptom in schizophrenia. Transcranial direct current stimulation (tDCS) and its more targeted variant, high-definition tDCS (HD-tDCS), have shown promising results in reducing AVH. We aimed to determine the effects of adjunctive HD-tDCS on various dimensions of AVH in patients with schizophrenia. This randomized controlled trial included 40 patients with schizophrenia with resistant AVH (20 patients each assigned to the active and sham group). A stimulation electrode was placed over the left temporoparietal junction at CP5 according to the 10-10 EEG montage, while return electrodes were positioned at C3, T7, P3, and P7. The active group received 2-mA current for 20 minutes, with a ramp-up and ramp-down of 3 seconds, whereas the sham group received 1-mA current for 30 seconds, with a 3-second ramp-up and ramp-down. AVH severity was assessed using the Psychotic Symptom Rating Scale-Auditory Hallucination at baseline, at the end of HD-tDCS sessions, and 4 weeks after completion. Within-group comparisons revealed significant improvements in both groups. However, in time*group comparison, the group receiving active HD-tDCS showed a statistically significant improvement only in the frequency dimension of AVH over time (p = 0.011). No other dimensions of AVH improved significantly in the time*group comparison. The effects of HD-tDCS were sustained up to 4 weeks. Active HD-tDCS over the left temporoparietal junction significantly reduced the frequency of AVH in patients with schizophrenia compared to sham stimulation. However, no significant improvements were observed in other domains of hallucination.

Transcranial Direct Current Stimulation Improves Paranoia and Social Functioning in Schizophrenia: A Randomized Clinical Trial.

Innovative treatments for paranoia, which significantly impairs social functioning in schizophrenia (SCZ), are urgently needed. The pathophysiology of paranoia implicates the amygdala-prefrontal (PFC) circuits; thus, this study systematically investigated whether transcranial direct current stimulation (tDCS) to the ventrolateral PFC can attenuate paranoia and improve social functioning in SCZ. A double-blind, within-subjects, crossover design was used to compare active vs. sham tDCS effects in 50 participants with SCZ (ClinicalTrials.gov Identifier: NCT05746494). Participants completed two stimulation visits, each including two tDCS sessions about a week apart, with active (2mA for 20mins) and sham conditions counterbalanced across the two visits. Alongside lab-based measurements of state paranoia and its associated social cognitive biases, Ecological Momentary Assessment (EMA) was used. This involved daily evaluations of paranoia and social functioning, administered three times per day for seven days in each EMA period (EMA-baseline, EMA-active, EMA-sham). For lab-based assessments, participants showed greater reductions in state paranoia and improvements in paranoia-related social cognitive biases after active stimulation compared to sham, including lower self-reported hostility and hostile attributions in ambiguous situations post-active versus post-sham. Similarly, in the EMA-active period, participants had lower daily paranoia compared to the EMA-sham period and higher social interaction motivation with better attitudes compared to baseline and the EMA-sham period. Extending our pilot study, the current findings further supported the efficacy of tDCS in SCZ patients in mitigating paranoia and enhancing social functioning. This work sheds light on the neuropathology of paranoia and identifies a promising avenue for future large-scale interventions.

A New Way to Treat Central Nervous System Dysfunction Caused by Musculoskeletal Injuries Using Transcranial Direct Current Stimulation: A Narrative Review

A New Way to Treat Central Nervous System Dysfunction Caused by Musculoskeletal Injuries Using Transcranial Direct Current Stimulation: A Narrative Review

Effects of Dual-Site Anodal Transcranial Direct Current Stimulation on Attention, Decision-Making, and Working Memory during Sports Fatigue in Elite Soccer Athletes.

Sports fatigue in soccer athletes has been shown to decrease neural activity, impairing cognitive function and negatively affecting motor performance. Transcranial direct current stimulation (tDCS) can alter cortical excitability, augment synaptic plasticity, and enhance cognitive function. However, its potential to ameliorate cognitive impairment during sports fatigue remains largely unexplored. This study investigated the effect of dual-site tDCS targeting the dorsolateral prefrontal cortex (DLPFC) or primary motor cortex (M1) on attention, decision-making, and working memory in elite soccer athletes during sports fatigue. Sports fatigue was induced in 23 (non-goalkeeper) elite soccer athletes, who then participated in three counterbalanced intervention sessions: dual-site tDCS over the M1, dual-site tDCS over the DLPFC, and sham tDCS. Following tDCS, participants completed the Stroop, Iowa Gambling, and 2-back tasks. We found a significant improvement in Stroop task accuracy following dual-site anodal tDCS over the M1 compared with the sham intervention in the incongruent condition (p = 0.036). Net scores in the Iowa Gambling task during blocks 4 (p = 0.019) and 5 (p = 0.014) significantly decreased under dual-site tDCS targeting the DLPFC compared with the sham intervention. No differences in 2-back task performance were observed between sessions (all p > 0.05). We conclude that dual-site anodal tDCS applied to the M1 enhanced attention performance while tDCS targeting the DLPFC increased risk propensity in a decision-making task during sports fatigue in elite soccer athletes. However, dual-site anodal tDCS targeting either the M1 or DLPFC did not significantly influence working memory performance during sports fatigue in this population. These preliminary findings suggest that dual-site tDCS targeting the M1 has beneficial effects on attention performance, potentially informing future research on sports fatigue in athletes. No: NCT06594978. Registered 09 September, 2024; https://clinicaltrials.gov/search?cond=NCT06594978.

Combining transcranial direct current stimulation and robotic-assisted training to address upper extremity deficits in acute disseminated encephalomyelitis: a case report

Combining transcranial direct current stimulation and robotic-assisted training to address upper extremity deficits in acute disseminated encephalomyelitis: a case report

DeepFocus: a transnasal approach for optimized deep brain stimulation of reward circuit nodes.

Transcranial electrical stimulation (TES) is an effective technique to modulate brain activity and treat diseases. However, TES is primarily used to stimulate superficial brain regions and is unable to reach deeper targets. The spread of injected currents in the head is affected by volume conduction and the additional spreading of currents as they move through head layers with different conductivities, as is discussed in [1]. In this paper, we introduce DeepFocus, a technique aimed at stimulating deep brain structures in the brain's "reward circuit" (e.g. the orbitofrontal cortex, Brodmann area 25, amygdala, etc.). To accomplish this, DeepFocus utilizes transnasal electrode placement (under the cribriform plate and within the sphenoid sinus) in addition to electrodes placed on the scalp, and optimizes current injection patterns across these electrodes. To quantify the benefit of DeepFocus, we develop the DeepROAST simulation and optimization platform. DeepROAST simulates the effect of complex skull-base bones' geometries on the electric fields generated by DeepFocus configurations using realistic head models. It also uses optimization methods to search for focal and efficient current injection patterns, which we use in our simulation and cadaver studies. In simulations, optimized DeepFocus patterns created larger and more focal fields in several regions of interest than scalp-only electrodes. In cadaver studies, DeepFocus patterns created large fields at the medial orbitofrontal cortex (OFC) with magnitudes comparable to stimulation studies, and, in conjunction with established cortical stimulation thresholds, suggest that the field intensity is sufficient to create neural response, e.g. at the OFC. This minimally invasive stimulation technique can enable more efficient and less risky targeting of deep brain structures to treat multiple neural conditions.&#xD.

Effect of Eight-Week Transcranial Direct-Current Stimulation Combined with Lat Pull-Down Resistance Training on Improving Pull-Up Performance for Male College Students.

The aim of this study was to investigate the effects and potential mechanisms of 8-week transcranial direct-current stimulation (tDCS) combined with resistance training (RT) on pull-up performance in male college students. Twenty-five male college students were randomly assigned to either RT combined with anodal tDCS stimulation (RT + tDCS) or RT alone (RT). Participants of both groups engaged in lat pull-down training programs for 8 weeks, with the RT + tDCS group receiving 20 min tDCS before each RT session. Pre- and post-intervention tests included pull-up endurance (number of repetitions), flexed arm circumference (FAC), and lat pull-down maximal voluntary isometric contraction (MVIC) peak force. During the pull-up endurance test, surface electromyography (sEMG) was recorded for the bicep brachii (BB), tricep brachii (TB), brachioradialis (BR), anterior deltoid (AD), middle deltoid (MD), posterior deltoid (PD), pectoralis major (PM), and latissimus dorsi (LD) muscles. Both groups demonstrated significant improvements in pull-up endurance and lat pull-down MVIC peak force after training, but no significant difference between the two groups was observed in the post-training test. Additionally, muscle activation of BR, PD, and PM decreased significantly in both groups, while the RT + tDCS group also demonstrated a significant reduction in TB coactivation after training. These findings suggest that eight weeks of tDCS combined with lat pull-down training and lat pull-down training alone can both significantly improve pull-up performance, which may be attributed to enhanced muscle contraction capacity. Although no significant training gains were found between the two training groups, the RT + tDCS group showed a significant decrease in TB coactivation and the enhancement of elbow flexion muscle contraction efficiency after training.

Comparison of stimulation sites enhancing dual-task performance using transcranial direct current stimulation in Parkinson’s disease

This pilot randomized crossover study aimed to compare the effects of stimulating various transcranial direct current stimulation (tDCS) target sites to improve dual-task performance in patients with Parkinson’s disease (PD). Nineteen patients with idiopathic PD completed four sessions of 2 mA anodal tDCS for 20 min at randomly assigned sites: the primary motor cortex (M1), left dorsolateral prefrontal cortex (DLPFC), ventromedial prefrontal cortex, and sham stimulation. Anodal M1 tDCS induced statistically significant improvements in single-task and cognitive dual-task timed up and go test. Additionally, enhancements were noted in the color-word Stroop test and trail-making test-Trail B following left DLPFC stimulation. However, none of the stimulation sites showed any significant changes in the dual-task effect. Overall, these results suggest that although tDCS targeting the M1 and DLPFC may immediately enhance motor and cognitive performances, respectively, neither has a significant effect on dual-task interference.

The safety and feasibility of transcranial direct current stimulation and exercise therapy for the treatment of cervicogenic headaches: A randomized pilot trial.

Our primary objective was to evaluate the safety and feasibility of transcranial direct current stimulation combined with exercise therapy for the treatment of cervicogenic headache. Our exploratory objectives compared symptoms of headache, mood, pain, and quality of life between active and sham transcranial direct stimulation combined with exercise therapy. Cervicogenic headache arises from injury to the cervical spine or degenerative diseases impacting cervical spine structure resulting in pain, reduced quality of life, and impaired function. Current standard-of-care treatments such as radiofrequency ablation, pharmacotherapy, manual therapy, and exercise therapy lack efficacy for some patients. Transcranial direct current stimulation is a neuromodulation technique that has shown promise in treating chronic pain conditions by positively altering neuronal activity but has not been evaluated as treatment for cervicogenic headache. This double-blind, sham-controlled, randomized, feasibility trial recruited 32 participants between the ages of 18 and 65 years that met the International Classification of Headache Disorders third edition criteria for cervicogenic headache. Participants were randomized to receive either active or sham transcranial direct current stimulation both combined with daily exercise therapy over 6 weeks. Transcranial direct current stimulation was applied over the primary motor cortex ipsilateral to worse pain for 20 min at 2 mA with a 30 s ramp up/down period. Recruitment, retention, and adherence were evaluated for feasibility. Safety was assessed through serious and minor adverse events and an adverse effect questionnaire. Clinical outcome measures assessed headache, pain, quality of life, and mood symptoms at pre-treatment, post-treatment, and 6- and 12-weeks post-treatment. A total of 97 participants were contacted to participate with 32 recruited, 16 randomized into each group, and 14 completing the treatment protocol in both groups. Within each group 12 (active) and nine (sham) completed treatment within the proposed 6 weeks (three sessions per week), others received 18 sessions but took longer. Exercise therapy was completed on an average of 87% of days for both groups. Transcranial direct current stimulation was safe, with no serious adverse events and one minor adverse event in the active group. Itching was a more common post-intervention complaint in the active group (64% active vs. 43% sham). Exploratory analysis revealed significant group × time interactions for average headache pain from pre- to post-treatment (β = -1.012, 95% confidence interval [CI] -1.751 to -0.273; p = 0.008), 6-weeks (β = -1.370, 95% CI -2.109 to -0.631; p < 0.001), and 12-weeks (β = -1.842, 95% CI -2.600 to -1.085; p < 0.001) post-treatment, and for neck pain from pre- to post-treatment (β = -1.184, 95% CI -2.076 to -0.292; p = 0.010) and 12-weeks (β = -1.029, 95% CI -1.944 to -0.114; p = 0.028) post-treatment favoring active vs. sham. There were no significant group × time interactions for quality of life or mood. The combination of transcranial direct stimulation and exercise therapy is safe and feasible for treating cervicogenic headache. While some promise has been shown for reducing headache and neck pain, larger scale trials with adequate power are needed to confirm these findings.

Non-invasive brain stimulation over the Frontopolar Cortex promotes willingness to exert cognitive effort in a foraging-like sequential choice task.

Individuals avoid spending cognitive effort unless expected rewards offset the perceived costs. Recent work employing tasks that provide explicit information about demands and incentives, suggests causal involvement of the Frontopolar Cortex (FPC) in effort-based decision-making. Using transcranial direct current stimulation (tDCS), we examined whether the FPC's role in motivating effort generalizes to sequential choice problems in which task demand and reward rates vary indirectly and as a function of experience. In a double-blind, within-subject design, 46 participants (36 female, 8 male, 1 'neither/other') received anodal (i.e., excitatory) or sham stimulation over the right FPC during an Effort Foraging Task, which required choosing between harvesting patches for successively decreasing resources or traveling to replenished patches by performing a cognitive task with environment-specific difficulty. As expected, participants exited patches later (i.e., exhibited lower exit thresholds) when travelling required greater (versus less) effort, indicating increased travel costs in high-effort environments. Under anodal tDCS, the difference in exit thresholds between environments was significantly smaller relative to sham. Finally, individual differences analyses hint that participants with lower self-reported motivation to exert effort exhibited greater travel cost reductions following tDCS. Together, these findings support the theorized causal role of the FPC in motivating cognitively effortful behavior, expand its role to more ecologically valid serial decisions and highlight the potential for tDCS as a tool to increase motivation with potential clinical applications.Significance statement Uncovering the neural mechanisms regulating engagement in effortful behavior is crucial, as it will improve our understanding and treatment of conditions characterized by reduced motivation, e.g., apathy and anhedonia. The Frontopolar Cortex (FPC) has been implicated in increasing effort exertion in settings that provide explicit information about effort demand and reward. Using transcranial direct current stimulation (tDCS), we investigated whether the FPC retains its motivating capacity in sequential choice problems that vary effort and reward indirectly. We demonstrate that FPC stimulation decreases cognitive effort-based travel costs in an Effort Foraging Task, indicating a causal and general involvement of the FPC in motivating effortful behavior, highlighting the potential of tDCS as a new avenue for increasing motivation with potential clinical applications.

Progress of the Exercise Therapy on Chronic Ankle Instability

This research delves into the effectiveness of various exercise therapies for Chronic Ankle Instability (CAI), a condition that frequently develops when initial ankle sprains are not adequately treated. CAI is characterized by repetitive sprains, joint instability, and reduced mobility, which can severely impact an individual's daily activities and sports performance. Different methods of rehabilitation, including muscle strengthening exercises, proprioceptive training, and balance improvement, were evaluated. The study emphasizes the advantages of combining traditional approaches such as resistance band exercises and newer techniques like blood flow restriction (BFR) training. These methods help enhance both strength and functionality in patients with CAI. Additionally, integrating proprioceptive exercises that focus on improving balance through unstable surface training has shown significant progress in restoring postural stability. Further, novel therapeutic interventions, including motor imagery, transcranial direct current stimulation (tDCS), and exergaming, demonstrate promising results in complementing traditional treatments. Ultimately, this review suggests a comprehensive rehabilitation plan that merges conventional and modern therapies to improve functional outcomes for individuals with CAI, though further research is necessary to optimize the combination of these therapies for long-term efficacy.

Dose–response of tDCS effects on motor learning and cortical excitability: A preregistered study

Abstract Multiple studies have demonstrated that transcranial direct current stimulation (tDCS) of the primary motor cortex (M1) can influence corticospinal excitability and motor skill acquisition. However, the evidence for these effects is inconsistent, and a common neural substrate for these effects has not been directly demonstrated. To address this, we hypothesized that higher tDCS intensities would produce more robust effects, and uncover their relationship. In this preregistered study, 120 participants engaged in a motor skill learning task while receiving tDCS with posterior-to-anterior currents through M1. We employed a double-blind, between-subjects design, with groups of 4 mA, 6 mA, or sham stimulation, while ensuring balanced groups in terms of typing speed. Cortical excitability was assessed via motor-evoked potentials (MEPs) and TMS-evoked potentials (TEPs) before and after motor skill learning with concurrent tDCS. tDCS at these higher intensities was well tolerated, and motor learning correlated with pretraining typing speed. Planned analyses found no dose–response effect of tDCS on motor skill performance or MEP amplitude. This suggests that, under our experimental conditions, tDCS did not significantly modulate motor skill learning or corticospinal excitability. Furthermore, there was no correlation between motor performance and MEP, and thus no evidence for a common neural substrate. Exploratory analyses found an increase in MEP and TEP amplitudes following the sequence learning task. Motor skill gains positively correlated with TEP changes over the stimulated M1, which were more negative with increasing tDCS intensity. The effects of tDCS on motor skill learning and MEPs, if they exist, may require particular experimental conditions that have not been tested here. Preregistration: https://osf.io/jyuev (in-principle acceptance: 2024/06/05)

Efficacy and safety of home-based transcranial direct current stimulation as adjunct treatment for cognitive improvement in major depressive disorder: A double-blind, randomized, multi-site clinical trial.

Transcranial direct current stimulation (tDCS) is a promising treatment for major depressive disorder (MDD). This study evaluated its antidepressant and cognitive effects as a safe, effective, home-based therapy for MDD. This double-blind, sham-controlled, randomized trial divided participants into low-intensity (1mA, n=47), high-intensity (2mA, n=49), and sham (n=45) groups, receiving 42 daily tDCS sessions, including weekends and holidays, targeting the dorsolateral prefrontal cortex for 30minutes. Assessments were conducted at baseline and weeks 2, 4, and 6. The primary outcome was cognitive improvement assessed by changes in total accuracy on the 2-back test from baseline to week 6. Secondary outcomes included changes in depressive symptoms (HAM-D), anxiety (HAM-A), and quality of life (QLES). Adverse events were monitored. This trial was registered with ClinicalTrials.gov (NCT04709952). In the tDCS study, of 141 participants (102 [72.3%] women; mean age 35.7years, standard deviation 12.7), 95 completed the trial. Mean changes in the total accuracy scores from baseline to week 6 were compared across the three groups using an F-test. Linear mixed-effects models examined the interaction of group and time. Results showed no significant differences among groups in cognitive or depressive outcomes at week 6. Active groups experienced more mild adverse events compared to sham but had similar rates of severe adverse events and dropout. Home-based tDCS for MDD demonstrated no evidence of effectiveness but was safe and well-tolerated. Further research is needed to address the technical limitations, evaluate broader cognitive functions, and extend durations to evaluate its therapeutic potential.

Advancing Neuroscience and Therapy: Insights into Genetic and Non-Genetic Neuromodulation Approaches.

Neuromodulation stands as a cutting-edge approach in the fields of neuroscience and therapeutic intervention typically involving the regulation of neural activity through physical and chemical stimuli. The purpose of this review is to provide an overview and evaluation of different neuromodulation techniques, anticipating a clearer understanding of the future developmental trajectories and the challenges faced within the domain of neuromodulation that can be achieved. This review categorizes neuromodulation techniques into genetic neuromodulation methods (including optogenetics, chemogenetics, sonogenetics, and magnetogenetics) and non-genetic neuromodulation methods (including deep brain stimulation, transcranial magnetic stimulation, transcranial direct current stimulation, transcranial ultrasound stimulation, photobiomodulation therapy, infrared neuromodulation, electromagnetic stimulation, sensory stimulation therapy, and multi-physical-factor stimulation techniques). By systematically evaluating the principles, mechanisms, advantages, limitations, and efficacy in modulating neuronal activity and the potential applications in interventions of neurological disorders of these neuromodulation techniques, a comprehensive picture is gradually emerging regarding the advantages and challenges of neuromodulation techniques, their developmental trajectory, and their potential clinical applications. This review highlights significant advancements in applying these techniques to treat neurological and psychiatric disorders. Genetic methods, such as sonogenetics and magnetogenetics, have demonstrated high specificity and temporal precision in targeting neuronal populations, while non-genetic methods, such as transcranial magnetic stimulation and photobiomodulation therapy, offer noninvasive and versatile clinical intervention options. The transformative potential of these neuromodulation techniques in neuroscience research and clinical practice is underscored, emphasizing the need for integration and innovation in technologies, the optimization of delivery methods, the improvement of mediums, and the evaluation of toxicity to fully harness their therapeutic potential.

Neuromodulatory effect of transcranial direct current stimulation on cue reactivity and craving in young adults with internet gaming disorder: an event-related potential study

ObjectiveThis study assessed the effects of transcranial direct current stimulation (tDCS) on cue reactivity and craving for game-related cues using event-related potentials (ERPs) in internet gaming disorder (IGD) patients.MethodsAt baseline, a series of game-related and neutral pictures were shown to both IGD and healthy controls (HCs) while ERPs were recorded. Late positive potentials (LPP) were used to investigate cue reactivity. During intervention, IGD patients received 10 sessions (two sessions/day for 5 consecutive days, 2 mA for 20 min/session) of tDCS to the left (anode stimulation) and right (cathode) dorsolateral prefrontal cortex. Subjectively assessed craving and LPP component was analyzed before stimulation and at the 1-month follow-up after tDCS in IGD.ResultsAt baseline, patients with IGD showed higher LPP amplitudes for game-related cues in the centro-parietal and parietal regions than HCs. After 10 sessions of tDCS, increased LPP amplitudes decreased significantly at 1-month follow-up., as well as subjective craving for gaming.ConclusionThese findings suggest that neurophysiological arousal in response to game-related cues in the IGD group could be modulated by the effects of tDCS. LPP was a significant neurophysiological marker of the neuroplastic response of cue reactivity underlying the therapeutic effect of tDCS on IGD. Based on the present findings, tDCS could be expanded to the treatment of other addictive disorders, including substance use disorder and behavioral addictions.

Identification of Cognitive Training for Individuals with Parkinson's Disease: A Systematic Review.

Background/Objectives: Parkinson's disease (PD) is a neurodegenerative disorder, characterised by cardinal motor features and a multitude of non-motor manifestations. Among them, cognitive impairment in PD has been recognised as a defined clinical entity, and it might lead to an increased risk of developing dementia. Consequently, the present review aimed to ascertain the available interventions for the training of cognitive abilities in persons with PD (PwPD). Methods: PRISMA guidelines were followed to select studies in the following databases: PubMed, PsycINFO, and Web of Science. Two independent reviewers conducted the different phases of the review, and a third expert was called in to address any doubts/conflicts. Randomised controlled trials and randomised clinical trials concerning cognitive training with cognitive outcomes in PwPD were selected. Results: A total of 28 articles were included. The considered studies applied various experimental interventions for the training of cognitive functions in PwPD: computer-based platforms, exergames, paper-and-pencil programmes, dual-task or treadmill training with action observation therapy, motor imagery, and virtual reality components, interventions targeting precise cognitive domain, tele-rehabilitation, transcranial direct current stimulation, structured cognitive training, and multimodal treatments. Cognitive functions were assessed employing neuropsychological tests, self-report questionnaires, and computerised batteries. Conclusions: Overall, the review reported better performances in the experimental groups compared to the control groups, in several cognitive domains. Structured cognitive training emerged as the most effective strategy to enhance cognitive functioning in PwPD. However, further studies are necessary to determine the most appropriate and useful training and to develop interventions that also consider patients' quality of life.

Improving locomotor performance with motor imagery and tDCS in young adults

The study aimed to assess the feasibility and potential efficacy of a non-motor intervention utilizing motor imagery (MI) and transcranial direct current stimulation (tDCS) to enhance motor function. The research involved a double-blind, randomized, controlled trial with three groups: MIActive, MISham, and Control. Participants engaged in a cognitively demanding obstacle course, with time and prefrontal activation (ΔO2Hb and ΔHHb) measured across three-time points (Baseline, Post-test, 1-week follow-up). Following a pretest, active or sham tDCS was administered during an MI session, while the Control group did not receive this intervention. The MIActive group showed significant improvements in time-to-completion immediately after the intervention and one week later. Additionally, ΔO2Hb levels were lower in the MIActive group than in the other groups. These findings suggest that the combination of MI and tDCS could lead to motor improvements. The study outcomes support the feasibility and initial effectiveness of using MI and tDCS as a non-motor intervention to enhance motor outcomes in short and medium terms. Further research is recommended to explore the impact of this intervention in individuals with existing motor impairments. This study contributes to the growing body of evidence on the potential of non-motor interventions to induce neuroplastic changes that improve motor function. Clinical trial registration: ClinicalTrials.gov, identifier NCT06414213 16/05/2024.

Transcranial direct current stimulation (tDCS) in psychiatric disorders in early childhood (aged under 10 years): a systematic review.

Transcranial direct current stimulation (tDCS) remains experimental for many psychiatric disorders in adults. Particularly in childhood, there is limited research on the evidence for the efficacy and mechanisms of action of tDCS on the developing brain. The objective of this review is to identify published experimental studies to examine the efficacy and mechanisms of tDCS in children with psychiatric or developmental disorders in early (prepubertal) childhood (aged under 10 years). Included Studies should meet the following criteria: (1) experimental studies (no reviews, no case reports), (2) studies published in international peer-reviewed journals, (3) written in English, (4) conducted on children under 10 under years of age, (5) at enrolment with a psychiatric or developmental disorder.Eight studies were identified that fulfilled the specified criteria. All studies investigated effect on children with autism-spectrum-disorder (ASD). Anodal tDCS, mainly targeting the left dorsolateral prefrontal cortex (dlPFC), showed positive effects on the reduction of ASD symptoms. There has also been evidence that these stimulations are feasible, have good tolerability and are safe. tDCS was found to be safe and partially effective, but a long-term effect of tDCS and changes in connectivity during tDCS in autism has not been proven. Other developmental or psychiatric diseases were not investigated. This results in a lack of knowledge regarding the reactivity of the brain during the prepubertal period, which is a critical phase in the pathogenesis of neurodevelopmental disorders such as attention deficit hyperactivity disorder (ADHD), ASD, Tourette's syndrome or dyslexia.

Time Dependent Effects of Cerebellar tDCS on Cerebello-cortical Connectivity Networks in Young Adults.

The cerebellum is involved in non-motor processing, supported by topographically distinct cerebellar activations and closed-loop circuits between the cerebellum and the cortex. Disruptions to cerebellar function may negatively impact prefrontal function and processing. Cerebellar resources may be important for offloading cortical processing, providing crucial scaffolding for normative performance and function. Here, we used transcranial direct current stimulation (tDCS) to temporarily alter cerebellar function and subsequently investigated resting state network connectivity. Critically, what happens to these circuits if the cerebellum is not functioning optimally, or after stimulation, remains relatively unknown. We employed a between-subjects design with 74 participants total (38 female; M = 22.0years, SD = 3.45), applying anodal (n = 25), cathodal (n = 25), or sham (n = 24) stimulation to the cerebellum to examine the effect of stimulation on cerebello-cortical resting state connectivity in young adults. We predicted increased functional connectivity following cathodal stimulation and decreased functional connectivity following anodal stimulation. We found, anodal stimulation resulted in increased connectivity in both ipsilateral and contralateral regions of the cortex, perhaps indicative of a compensatory response to degraded cerebellar output. Additionally, a window analysis also demonstrated a time dependent nature to the impacts of cerebellar tDCS on connectivity, particularly with cognitive regions of the cerebral cortex. This work suggests that when cerebellar outputs are degraded, in this case by tDCS, the cerebellum offloads its processing responsibility which encourages more cortical regions to engage to compensate for the degraded cerebellar output. This results in in differences in cortical activation patterns and performance deficits. These results might inform and update existing compensatory models, which focus primarily on the cortex, to include the cerebellum as a vital structure involved in the scaffolding of cortical processing.

The effects of transcranial direct current stimulation on global cognition in patients with Alzheimer's disease: An update meta-analysis.

Alzheimer's disease (AD) is a neurodegenerative disease. At present, there are currently no drugs that can cure AD. A number of empirical studies have shown that transcranial direct current stimulation (tDCS) may be used to treat cognitive abnormalities in patients with AD. We will through meta-analysis reviews tDCS overall research on the effects of cognitive function in patients with AD. Systematic searches were performed in the PubMed, Embase, and Cochrane Library databases from their creation until 8 March 2024. Using a fixed effect model and random effect model to evaluate the average difference between the treatment group and control group (MD) and its 95% confidence interval (CI). The study included 10 randomized controlled trials (Nactive = 165, Nsham = 167). The results of the overall analysis showed that tDCS did not significantly improve the overall cognitive function (SMD = 0.17; 95%CI = -0.05, 0.39; p = 0.14; I² = 51%). Quality of life of AD patients after treatment was also evaluated, but no improvement was seen. Subgroup analysis showed no significant improvement in global cognitive function after tDCS treatment. The sensitivity analysis to confirm the reliability of the data, risk assessment did not find any high-risk projects. The tDCS treatment did not improve cognitive function in patients with AD. Further empirical research in the future will help to explore new schemes for tDCS to improve cognitive function of patients.