-
Frontiers in Human Neuroscience 2023Disorders of consciousness (DoC) commonly occurs secondary to severe neurological injury. A considerable volume of research has explored the effectiveness of different...
BACKGROUND
Disorders of consciousness (DoC) commonly occurs secondary to severe neurological injury. A considerable volume of research has explored the effectiveness of different non-invasive neuromodulation therapy (NINT) on awaking therapy, however, equivocal findings were reported.
OBJECTIVE
The aim of this study was to systematically investigate the effectiveness on level of consciousness of different NINT in patients with DoC and explore optimal stimulation parameters and characteristics of patients.
METHODS
PubMed, Embase, Web of Science, Scopus, and Cochrane central register of controlled trials were searched from their inception through November 2022. Randomized controlled trials, that investigated effectiveness on level of consciousness of NINT, were included. Mean difference (MD) with 95% confidence interval (CI) was evaluated as effect size. Risk of bias was assessed with revised Cochrane risk-of-bias tool.
RESULTS
A total of 15 randomized controlled trials with 345 patients were included. Meta-analysis was performed on 13 out of 15 reviewed trials indicating that transcranial Direct Current Stimulation (tDCS), Transcranial Magnetic Stimulation (TMS), and median nerve stimulation (MNS) all had a small but significant effect (MD 0.71 [95% CI 0.28, 1.13]; MD 1.51 [95% CI 0.87, 2.15]; MD 3.20 [95%CI: 1.45, 4.96]) on level of consciousness. Subgroup analyses revealed that patients with traumatic brain injury, higher initial level of consciousness (minimally conscious state), and shorter duration of prolonged DoC (subacute phase of DoC) reserved better awaking ability after tDCS. TMS also showed encouraging awaking effect when stimulation was applied on dorsolateral prefrontal cortex in patients with prolonged DoC.
CONCLUSION
tDCS and TMS appear to be effective interventions for improving level of consciousness of patients with prolonged DoC. Subgroup analyses identified the key parameters required to enhance the effects of tDCS and TMS on level of consciousness. Etiology of DoC, initial level of consciousness, and phase of DoC could act as significant characteristics of patients related to the effectiveness of tDCS. Stimulation site could act as significant stimulation parameter related to the effectiveness of TMS. There is insufficient evidence to support the use of MNS in clinical practice to improve level of consciousness in patients with coma.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=337780, identifier: CRD42022337780.
PubMed: 37292582
DOI: 10.3389/fnhum.2023.1129254 -
Clinical Neurophysiology : Official... Dec 2022Alzheimer's disease dementia (AD) and its preclinical stage, mild cognitive impairment (MCI), are critical issues confronting the aging society. Non-invasive brain... (Meta-Analysis)
Meta-Analysis
OBJECTIVE
Alzheimer's disease dementia (AD) and its preclinical stage, mild cognitive impairment (MCI), are critical issues confronting the aging society. Non-invasive brain stimulation (NIBS) techniques have the potential to be effective tools for enhancing cognitive functioning. The main objective of our meta-analysis was to quantify and update the status of the efficacy of repetitive Transcranial Magnetic Stimulation (rTMS) and Transcranial Direct Current Stimulation (tDCS) when applied in AD and MCI.
METHODS
The systematic literature search was conducted in PubMed and Web of Science according to PRISMA statement.
RESULTS
Pooled effect sizes (Hedges' g) from 32 studies were analyzed using random effect models. We found both, rTMS and tDCS to have significant immediate cognition-enhancing effect in AD with rTMS inducing also beneficial long-term effects. We found no evidence for synergistic effect of cognitive training with NIBS.
CONCLUSIONS
In AD a clinical recommendation can be made for NEURO-AD system and for high-frequency rTMS over the left dorsolateral prefrontal cortex (DLPFC) as probably effective protocols (B-level of evidence) and for anodal tDCS over the left DLPFC as a possibly effective.
SIGNIFICANCE
According to scientific literature, NIBS may be an effective method for improving cognition in AD and possibly in MCI.
Topics: Humans; Alzheimer Disease; Brain; Cognition; Cognitive Dysfunction; Transcranial Direct Current Stimulation; Transcranial Magnetic Stimulation
PubMed: 36215904
DOI: 10.1016/j.clinph.2022.09.010 -
Journal of Psychiatric Research Feb 2024Based on existing evidence of the effects of the most commonly used non-invasive brain stimulation (NIBS), which includes transcranial magnetic stimulation (TMS) and... (Meta-Analysis)
Meta-Analysis Review
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, I = 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, I = 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.
Topics: Humans; Transcranial Direct Current Stimulation; Schizophrenia; Transcranial Magnetic Stimulation; Cognition; Cognitive Dysfunction; Brain; Randomized Controlled Trials as Topic
PubMed: 38150769
DOI: 10.1016/j.jpsychires.2023.12.003 -
Journal of Affective Disorders Jan 2022Bipolar disorders (BD) are serious mental health disorders that impacts on cognitive and social functioning. We aimed to systematically review and conduct a... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Bipolar disorders (BD) are serious mental health disorders that impacts on cognitive and social functioning. We aimed to systematically review and conduct a meta-analysis of fMRI correlates of working memory in euthymic people with BD compared to healthy participants.
METHOD
Web of Science, Embase and PubMed databases were systematically searched to identify studies which examined the fMRI correlates of working memory function in euthymic people with BD and healthy participants. Relevant demographic, behavioral and functional MRI (fMRI) data was qualitatively and quantitatively assessed, and the quality of the included studies evaluated. Comparable studies which used the same working memory task were included in a meta-analysis using Seed-Based D Mapping software (SDM).
RESULTS
Twenty-four studies were included in this systematic review. Consistent brain fMRI activity differences were found in key brain areas of the working memory network in euthymic people with BD compared to healthy participants including the ventromedial and dorsolateral prefrontal cortices. Cognitive performance was not significantly different between the two groups. Six studies were suitable to be included in the meta-analysis. There was no significant overlap in areas of brain activation after family-wise correction for multiple comparisons.
LIMITATIONS
Heterogeneity of task paradigms, small sample sizes and inherent difficulty in the interpretation of functional brain activity due to variations between studies were all limitations.
CONCLUSION
The differences in working memory related fMRI activity identified by this study between people with BD and healthy participants are consistent with existing literature reporting impaired working memory performance in BD. This was not accompanied by significant differences in cognitive performance in the reviewed studies, likely due to small sample sizes. Further studies are needed to investigate the relationship between differential brain activity and working memory performance in people with BD.
Topics: Bipolar Disorder; Brain; Cyclothymic Disorder; Dorsolateral Prefrontal Cortex; Humans; Magnetic Resonance Imaging; Memory, Short-Term
PubMed: 34715175
DOI: 10.1016/j.jad.2021.10.084 -
Frontiers in Psychiatry 2023Intermittent theta-burst stimulation (iTBS), which is a form of repetitive transcranial magnetic stimulation (rTMS), can produce 600 pulses to the left dorsolateral...
Efficacy and safety of intermittent theta burst stimulation versus high-frequency repetitive transcranial magnetic stimulation for patients with treatment-resistant depression: a systematic review.
OBJECTIVE
Intermittent theta-burst stimulation (iTBS), which is a form of repetitive transcranial magnetic stimulation (rTMS), can produce 600 pulses to the left dorsolateral prefrontal cortex (DLPFC) in a stimulation time of just over 3 min. The objective of this systematic review was to compare the safety and efficacy of iTBS and high-frequency (≥ 5 Hz) rTMS (HF-rTMS) for patients with treatment-resistant depression (TRD).
METHODS
Randomized controlled trials (RCTs) comparing the efficacy and safety of iTBS and HF-rTMS were identified by searching English and Chinese databases. The primary outcomes were study-defined response and remission.
RESULTS
Two RCTs ( = 474) investigating the efficacy and safety of adjunctive iTBS ( = 239) versus HF-rTMS ( = 235) for adult patients with TRD met the inclusion criteria. Among the two included studies (Jadad score = 5), all were classified as high quality. No group differences were found regarding the overall rates of response (iTBS group: 48.0% versus HF-rTMS group: 45.5%) and remission (iTBS group: 30.0% versus HF-rTMS group: 25.2%; all > 0.05). The rates of discontinuation and adverse events such as headache were similar between the two groups (all > 0.05).
CONCLUSION
The antidepressant effects and safety of iTBS and HF-rTMS appeared to be similar for patients with TRD, although additional RCTs with rigorous methodology are needed.
PubMed: 37583841
DOI: 10.3389/fpsyt.2023.1244289 -
Frontiers in Human Neuroscience 2020The transcranial direct current stimulation (tDCS) is a neuromodulatory technique with the potential to decrease pain scores and to improve chronic pain treatment....
The transcranial direct current stimulation (tDCS) is a neuromodulatory technique with the potential to decrease pain scores and to improve chronic pain treatment. Although age is an essential factor that might impact the tDCS effect, most studies are solely conducted in adults. Therefore, the age limitation presents a critical research gap in this field and can be shown by only a handful of studies that have included other age groups. To examine the evidence upon the tDCS effect on pain scores on children, adolescents, or elderly, and indirectly, to infer the age-dependent impact on tDCS effects, we conducted a systematic review and meta-analysis. A systematic review searching the following databases: PubMed, EMBASE, and Science Direct using the following search terms adapted according to MeSh or Entree: [("Adolescent" OR "Children" OR "Elderly") AND ("tDCS") AND ("Pain" OR "Pain threshold") AND ("dorsolateral prefrontal cortex" OR "Motor cortex)] up to April 20th, 2020. We retrieved 228 articles, 13 were included in the systematic review, and five studies with elderly subjects that had their outcomes assessed by pain score or pain threshold were included in the meta-analysis. For the analysis of pain score, 96 individuals received active stimulation, and we found a favorable effect for active tDCS to reduce pain score compared to sham ( = 0.002). The standardized difference was -0.76 (CI 95% = -1.24 to -0.28). For the pain threshold, the analysis showed no significant difference between active and sham tDCS. We reviewed two studies with adolescents: one study using anodal tDCS over the prefrontal cortex reported a reduction in pain scores. However, the second study reported an increase in pain sensitivity for the dorsolateral prefrontal cortex (DLPFC) stimulation. Our findings suggest tDCS may reduce pain levels in the elderly group. Nevertheless, the small number of studies included in this review-and the considerable heterogeneity for clinical conditions and protocols of stimulation present-limits the support of tDCS use for pain treatment in elderly people. Larger studies on the tDCS effect on pain are needed to be conducted in elderly and adolescents, also evaluating different montages and electrical current intensity.
PubMed: 33192397
DOI: 10.3389/fnhum.2020.568306 -
General Hospital Psychiatry 2024Several types of neuromodulation have been investigated for the treatment of fibromyalgia, but they show varied efficacy on pain, functioning, comorbid depression and... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
Several types of neuromodulation have been investigated for the treatment of fibromyalgia, but they show varied efficacy on pain, functioning, comorbid depression and comorbid anxiety. Whether some types of neuromodulation or some factors are associated with a better response also awaits clarification.
METHODS
We conducted a systematic review and network meta-analysis of randomized controlled trials to evaluate the efficacy of neuromodulation in patients with fibromyalgia. We searched PubMed, EMBASE, the Cochrane Central Register of Controlled Trials and PsycINFO before March 2022. We employed a frequentist random-effects network meta-analysis.
RESULTS
Forty trials involving 1541 participants were included. Compared with sham control interventions, several types of transcranial direct current stimulation (tDCS), transcranial random noise stimulation (tRNS), and high-frequency repetitive transcranial magnetic stimulation (rTMS) were associated with significant reduction of pain, depression, anxiety, and improvement in functioning. Many significantly effective treatment options involve stimulation of the primary motor cortex or dorsolateral prefrontal cortex.
CONCLUSION
We concluded that several types of rTMS, tDCS and tRNS may have the potential to be applied for clinical purposes.
Topics: Humans; Fibromyalgia; Transcranial Direct Current Stimulation; Network Meta-Analysis; Transcranial Magnetic Stimulation; Pain; Treatment Outcome
PubMed: 38382420
DOI: 10.1016/j.genhosppsych.2024.01.007 -
Transcranial Direct Current Stimulation on Parkinson's Disease: Systematic Review and Meta-Analysis.Frontiers in Neurology 2021Clinical impact of transcranial direct current stimulation (tDCS) alone for Parkinson's disease (PD) is still a challenge. Thus, there is a need to synthesize available...
Clinical impact of transcranial direct current stimulation (tDCS) alone for Parkinson's disease (PD) is still a challenge. Thus, there is a need to synthesize available results, analyze methodologically and statistically, and provide evidence to guide tDCS in PD. Investigate isolated tDCS effect in different brain areas and number of stimulated targets on PD motor symptoms. A systematic review was carried out up to February 2021, in databases: Cochrane Library, EMBASE, PubMed/MEDLINE, Scopus, and Web of science. Full text articles evaluating effect of active tDCS (anodic or cathodic) vs. sham or control on motor symptoms of PD were included. Ten studies ( = 236) were included in meta-analysis and 25 studies ( = 405) in qualitative synthesis. The most frequently stimulated targets were dorsolateral prefrontal cortex and primary motor cortex. No significant effect was found among single targets on motor outcomes: Unified Parkinson's Disease Rating Scale (UPDRS) III - motor aspects (MD = -0.98%, 95% CI = -10.03 to 8.07, = 0.83, = 0%), UPDRS IV - dyskinesias (MD = -0.89%, CI 95% = -3.82 to 2.03, = 0.55, = 0%) and motor fluctuations (MD = -0.67%, CI 95% = -2.45 to 1.11, = 0.46, = 0%), timed up and go - gait (MD = 0.14%, CI 95% = -0.72 to 0.99, = 0.75, = 0%), Berg Balance Scale - balance (MD = 0.73%, CI 95% = -1.01 to 2.47, = 0.41, = 0%). There was no significant effect of single vs. multiple targets in: UPDRS III - motor aspects (MD = 2.05%, CI 95% = -1.96 to 6.06, = 0.32, = 0%) and gait (SMD = -0.05%, 95% CI = -0.28 to 0.17, = 0.64, = 0%). Simple univariate meta-regression analysis between treatment dosage and effect size revealed that number of sessions (estimate = -1.7, SE = 1.51, z-score = -1.18, = 0.2, IC = -4.75 to 1.17) and cumulative time (estimate = -0.07, SE = 0.07, z-score = -0.99, = 0.31, IC = -0.21 to 0.07) had no significant association. There was no significant tDCS alone short-term effect on motor function, balance, gait, dyskinesias or motor fluctuations in Parkinson's disease, regardless of brain area or targets stimulated.
PubMed: 35082749
DOI: 10.3389/fneur.2021.794784 -
Frontiers in Human Neuroscience 2021Anxiety disorders are among the most prevalent mental disorders. Present treatments such as cognitive behavior therapy and pharmacological treatments show only moderate...
Anxiety disorders are among the most prevalent mental disorders. Present treatments such as cognitive behavior therapy and pharmacological treatments show only moderate success, which emphasizes the importance for the development of new treatment protocols. Non-invasive brain stimulation methods such as repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) have been probed as therapeutic option for anxiety disorders in recent years. Mechanistic information about their mode of action, and most efficient protocols is however limited. Here the fear extinction model can serve as a model of exposure therapies for studying therapeutic mechanisms, and development of appropriate intervention protocols. We systematically reviewed 30 research articles that investigated the impact of rTMS and tDCS on fear memory and extinction in animal models and humans, in clinical and healthy populations. The results of these studies suggest that tDCS and rTMS can be efficient methods to modulate fear memory and extinction. Furthermore, excitability-enhancing stimulation applied over the vmPFC showed the strongest potential to enhance fear extinction. We further discuss factors that determine the efficacy of rTMS and tDCS in the context of the fear extinction model and provide future directions to optimize parameters and protocols of stimulation for research and treatment.
PubMed: 33828472
DOI: 10.3389/fnhum.2021.655947 -
Translational Psychiatry May 2020Approximately 7-9% of people develop posttraumatic stress disorder in their lifetime, but standard pharmacological treatment or psychotherapy shows a considerable... (Meta-Analysis)
Meta-Analysis Review
Approximately 7-9% of people develop posttraumatic stress disorder in their lifetime, but standard pharmacological treatment or psychotherapy shows a considerable individual variation in their effectiveness. Repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) hold promise for the treatment of posttraumatic stress disorder. The objective of this meta-analysis was to summarize the existing evidence on the therapeutic effects of these brain stimulation treatments on posttraumatic core symptoms. We systematically retrieved articles published between 1st January 2000 and 1st January 2020 comparing the effects of active with sham stimulation or no intervention in posttraumatic patients from eight databases. Random-effects model was used for meta-analysis. Meta-regression and subgroup meta-analysis was performed to investigate the influence of stimulation dose and different stimulation protocols, respectively. 20 studies were included in this review, where of 11 randomized controlled trials were subjected to quantitative analysis. Active stimulation demonstrated significant reductions of core posttraumatic symptoms with a large effect size (Hedge's g = -0.975). Subgroup analysis showed that both excitatory and inhibitory rTMS of the right dorsolateral prefrontal cortex led to symptom reductions with a large (Hedges' g = -1.161, 95% CI, -1.823 to -0.499; p = 0.015) and medium effect size (Hedges' g = -0.680, 95% CI: -0.139 to -0.322; p ≤ 0.001) respectively. Results further indicated significant durability of symptom-reducing effects of treatments during a two to four weeks period post stimulation (Hedges' g = -0.909, 95% CI: -1.611 to -0.207; p = 0.011). rTMS of the right dorsolateral prefrontal cortex appears to have a positive effect in reducing core symptoms in patients with posttraumatic stress disorder.
Topics: Humans; Prefrontal Cortex; Stress Disorders, Post-Traumatic; Transcranial Direct Current Stimulation; Transcranial Magnetic Stimulation
PubMed: 32467579
DOI: 10.1038/s41398-020-0851-5