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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 -
Psychiatry Research 2012This meta-analysis evaluates alterations of neurometabolites in schizophrenia and bipolar disorder. PubMed was searched to find controlled studies evaluating... (Meta-Analysis)
Meta-Analysis Review
This meta-analysis evaluates alterations of neurometabolites in schizophrenia and bipolar disorder. PubMed was searched to find controlled studies evaluating N-acetylaspartate (NAA), Choline (Cho) and Creatine (Cr) assessed with ((1))H-MRS (proton magnetic resonance spectroscopy) in patients with schizophrenia and bipolar disorder up to September 2010. Random effects meta-analyses were conducted to estimate pooled standardized mean differences. The statistic was used to quantify inconsistencies. Subgroup analyses were conducted to explore potential explanations for inconsistencies. The systematic review included 146 studies with 5643 participants. NAA levels were affected in schizophrenia and bipolar disorder. Decreased levels in the basal ganglia and frontal lobe were the most consistent findings in schizophrenia; decreased levels in the basal ganglia were the most consistent findings in bipolar disorder. Cho and Cr levels were not altered in either disorder. Findings for Cr were most consistent in the thalamus, frontal lobe and dorsolateral prefrontal cortex in schizophrenia and the basal ganglia and frontal lobe in bipolar disorder. Findings for Cho were most consistent in the thalamus, frontal lobe and anterior cingulate cortex in schizophrenia and basal ganglia in bipolar disorder. Large, carefully designed studies are needed to better estimate the extent of alterations in neurometabolites.
Topics: Aspartic Acid; Basal Ganglia; Bipolar Disorder; Choline; Creatine; Gyrus Cinguli; Humans; Magnetic Resonance Spectroscopy; Prefrontal Cortex; Reference Values; Schizophrenia; Schizophrenic Psychology; Thalamus
PubMed: 22981426
DOI: 10.1016/j.pscychresns.2012.02.003 -
Frontiers in Neuroscience 2023Post-stroke cognitive impairment (PSCI) is a significant health concern. Transcranial magnetic stimulation (TMS) is considered a promising rehabilitation therapy for...
Effects of excitatory transcranial magnetic stimulation over the different cerebral hemispheres dorsolateral prefrontal cortex for post-stroke cognitive impairment: a systematic review and meta-analysis.
BACKGROUND
Post-stroke cognitive impairment (PSCI) is a significant health concern. Transcranial magnetic stimulation (TMS) is considered a promising rehabilitation therapy for improving cognition, and the effects of excitatory TMS on PSCI have received much attention in recent years. However, the effects of different cerebral hemispheres on excitatory TMS treatment of cognitive impairment have not been studied. This review aimed to study the effects of excitatory TMS over the dorsolateral prefrontal cortex (DLPFC) of different cerebral hemispheres on the cognitive function of patients with PSCI.
METHODS
Literature published in PubMed, Web of Science, Embase, Cochrane Library, Scopus, and Wiley from inception to September 30, 2022, were searched. Two researchers independently performed literature screening, data extraction, and quality assessment. Furthermore, we conducted a meta-analysis using RevMan software (version 5.4) and rated the strength of evidence using GRADEpro.
RESULTS
A total of 19 studies were included in this meta-analysis. The results showed that excitatory TMS over the left hemisphere DLPFC was significantly better in improving global cognition (SMD = 2.26, 95% CI 1.67-2.86, < 0.00001; vs. SMD = 2.53, 95% CI 1.86-3.20, < 0.00001), memory (SMD = 1.29, 95% CI 0.72-1.87, < 0.0001), attention (SMD = 2.32, 95% CI 1.64-3.01, < 0.00001), executive (SMD = 0.64, 95% CI 0.21-1.07, = 0.004), P300 latency (SMD = 2.69, 95% CI 2.13-3.25, < 0.00001), and depression (SMD = 0.95, 95% CI 0.26-1.63, = 0.007) than that of the control group, but the effect on improving activities of daily living (ADL) was unclear ( = 0.03 vs. = 0.17). Subgroup analysis further showed that excitatory TMS over the right hemisphere DLPFC was effective in improving the global cognition of PSCI patients ( < 0.00001), but the stimulation effect over the ipsilateral hemisphere DLPFC was unclear ( = 0.11 vs. = 0.003). Additionally, excitatory TMS over the ipsilateral hemisphere DLPFC showed no statistical difference in improving ADL between the two groups ( = 0.25).
CONCLUSIONS
Compared to other hemispheric sides, excitatory TMS over the left hemisphere DLPFC was a more effective stimulation area, which can significantly improved the global cognitive function, memory, attention, executive, P300 latency, and depression in patients with PSCI. There was no apparent therapeutic effect on improving activities of daily living (ADL). In the future, more randomized controlled trials with large-sample, high quality, and follow-up are necessary to explore a usable protocol further.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42022369096.
PubMed: 37260845
DOI: 10.3389/fnins.2023.1102311 -
Brain Stimulation 2021High-frequency rTMS over the dorsolateral prefrontal cortex (DLPFC) has demonstrated mixed effects on chronic and provoked pain. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
High-frequency rTMS over the dorsolateral prefrontal cortex (DLPFC) has demonstrated mixed effects on chronic and provoked pain.
OBJECTIVES/METHODS
In this study, a meta-analysis was conducted to characterise the potential analgesic effects of high-frequency rTMS over the DLPFC on both chronic and provoked pain.
RESULTS
A total of 626 studies were identified in a systematic search. Twenty-six eligible studies were included for the quantitative review, among which 17 modulated chronic pain and the remaining investigated the influence on provoked pain. The left side DLPFC was uniformly targeted in the chronic pain studies. While our data identified no overall effect of TMS across chronic pain conditions, there was a significant short-term analgesia in neuropathic pain conditions only (SMD = -0.87). In terms of long-lasting analgesia, there was an overall pain reduction in the midterm (SMD = -0.53, 24.6 days average) and long term (SMD = -0.63, 3 months average) post DLPFC stimulation, although these effects were not observed within specific chronic pain conditions. Surprisingly, the number of sessions was demonstrated to have no impact on rTMS analgesia. In the analysis of provoked pain, our data also indicated a significant analgesic effect following HF-rTMS over the DLPFC (SMD = -0.73). Importantly, we identified a publication bias in the studies of provoked pain but not for chronic pain conditions.
CONCLUSIONS
Overall, our findings support that HF-DLPFC stimulation is able to induce an analgesic effect in chronic pain and in response to provoked pain. These results highlight the potential of DLPFC-rTMS in the management of certain chronic pain conditions and future directions are discussed to enhance the potential long-term analgesic effects.
Topics: Chronic Pain; Humans; Pain Management; Pain Measurement; Prefrontal Cortex; Transcranial Magnetic Stimulation
PubMed: 34280583
DOI: 10.1016/j.brs.2021.07.004 -
Frontiers in Neurology 2023Transcranial magnetic stimulation (TMS) is a non-invasive intervention that holds promise for improving cognitive function in individuals with Alzheimer's disease (AD)....
INTRODUCTION
Transcranial magnetic stimulation (TMS) is a non-invasive intervention that holds promise for improving cognitive function in individuals with Alzheimer's disease (AD). However, the effectiveness of this therapy and the optimal TMS parameters has not reached a consensus. The purpose of the meta-analysis was to systematically discern the effectiveness of different components of TMS protocols on cognitive improvement in patients with mild cognitive impairment (MCI) and AD.
METHODS
The meta-analysis was preregistered on Prospero (registration number: CRD42022345482). PubMed, Web of Science, Science Direct, and Cochrane Library databases were used to search, screen and identify eligible studies with the following keywords: Transcranial Magnetic Stimulation OR TMS OR theta burst stimulation AND Alzheimer OR Alzheimers OR Alzheimer's OR mild cognitive impairment OR MCI. Randomized controlled trials (RCTs) of participants with accepted standardized diagnostic criteria were searched by two authors independently. The risk of bias was assessed using an adapted Cochrane Risk of Bias tool. Standardized mean difference (SMD) and 95% confidence interval (CI) were calculated using the random-effects models. Subgroup analyses were performed to investigate the influential factors.
RESULTS
A total of 21 studies and 25 trials were included in this meta-analysis. The findings revealed a significant overall cognition improvement of real stimulation compared with sham stimulation (short-term effects: SMD, 0.91; 95% CI 0.44-1.38; < 0.01; long-lasting effects: SMD, 0.91; 95% CI 0.27-1.55; < 0.01). Subgroup analysis demonstrated that stimulation of the left dorsolateral prefrontal cortex and bilateral cerebellums, as well as moderate frequency stimulation (5 Hz and 10 Hz) on mild and moderate cognitive impairment patients, were more effective than other TMS protocols. However, the additional application of cognitive training showed no significant improvement.
CONCLUSION
Cognitive improvement effect of TMS was demonstrated in MCI and AD patients in both short-term assessment and long-lasting outcomes, and the efficiency of TMS is affected by the stimulation frequency, stimulation site, and participant characteristics. Further RCTs are needed to validate the findings of our subgroup analysis.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022345482, identifier: CRD42022345482.
PubMed: 37528850
DOI: 10.3389/fneur.2023.1209205 -
Neuropsychology Review Mar 2016Oppositional defiant disorder (ODD) and conduct disorder (CD) are common behavioural disorders in childhood and adolescence and are associated with brain abnormalities.... (Meta-Analysis)
Meta-Analysis Review
A Systematic Review and Meta-analysis of Neuroimaging in Oppositional Defiant Disorder (ODD) and Conduct Disorder (CD) Taking Attention-Deficit Hyperactivity Disorder (ADHD) Into Account.
Oppositional defiant disorder (ODD) and conduct disorder (CD) are common behavioural disorders in childhood and adolescence and are associated with brain abnormalities. This systematic review and meta-analysis investigates structural (sMRI) and functional MRI (fMRI) findings in individuals with ODD/CD with and without attention-deficit hyperactivity disorder (ADHD). Online databases were searched for controlled studies, resulting in 12 sMRI and 17 fMRI studies. In line with current models on ODD/CD, studies were classified in hot and cool executive functioning (EF). Both the meta-analytic and narrative reviews showed evidence of smaller brain structures and lower brain activity in individuals with ODD/CD in mainly hot EF-related areas: bilateral amygdala, bilateral insula, right striatum, left medial/superior frontal gyrus, and left precuneus. Evidence was present in both structural and functional studies, and irrespective of the presence of ADHD comorbidity. There is strong evidence that abnormalities in the amygdala are specific for ODD/CD as compared to ADHD, and correlational studies further support the association between abnormalities in the amygdala and ODD/CD symptoms. Besides the left precuneus, there was no evidence for abnormalities in typical cool EF related structures, such as the cerebellum and dorsolateral prefrontal cortex. Resulting areas are associated with emotion-processing, error-monitoring, problem-solving and self-control; areas associated with neurocognitive and behavioural deficits implicated in ODD/CD. Our findings confirm the involvement of hot, and to a smaller extent cool, EF associated brain areas in ODD/CD, and support an integrated model for ODD/CD (e.g. Blair, Development and Psychopathology, 17(3), 865-891, 2005).
Topics: Adolescent; Adult; Attention Deficit Disorder with Hyperactivity; Attention Deficit and Disruptive Behavior Disorders; Brain; Brain Mapping; Child; Conduct Disorder; Female; Humans; Magnetic Resonance Imaging; Male; Young Adult
PubMed: 26846227
DOI: 10.1007/s11065-015-9315-8 -
Neurologia 2023Fibromyalgia syndrome (FM) is a chronic pathology characterised by widespread pain commonly associated with psychological distress affecting quality of life. In recent... (Review)
Review
BACKGROUND
Fibromyalgia syndrome (FM) is a chronic pathology characterised by widespread pain commonly associated with psychological distress affecting quality of life. In recent years, transcranial direct current stimulation (tDCS) and transcranial magnetic stimulation (TMS) have been investigated to treat chronic pain. The aim of the current review is to determine the effects of tDCS and TMS on the main symptoms of patients with FM.
DEVELOPMENT
A systematic review based on PRISMA guidelines was carried out. The search strategy was performed in MEDLINE, SCOPUS, PEDro and Cochrane Library. Randomised controlled trials based on the effects of tDCS and TMS on pain, pressure pain threshold (PPT), fatigue, anxiety and depression, catastrophising and quality of life in patients with FM were analysed. Fourteen studies were included.
CONCLUSIONS
The application of tDCS to the motor cortex is the only intervention shown to decrease pain in the short and medium-term in patients with FM. The application of both interventions showed improvements in PPT, catastrophising and quality of life when applied to the motor cortex, and in fatigue when applied to the dorsolateral prefrontal cortex. The effects of these interventions on anxiety and depression are unclear.
Topics: Humans; Transcranial Direct Current Stimulation; Transcranial Magnetic Stimulation; Fibromyalgia; Quality of Life; Chronic Pain; Fatigue
PubMed: 37031798
DOI: 10.1016/j.nrleng.2020.07.025 -
Brain and Cognition Apr 2014Recent studies have used non-invasive brain stimulation (NIBS) techniques, such as repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current... (Meta-Analysis)
Meta-Analysis Review
Recent studies have used non-invasive brain stimulation (NIBS) techniques, such as repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS), to increase dorsolateral prefrontal cortex (DLPFC) activity and, consequently, working memory (WM) performance. However, such experiments have yielded mixed results, possibly due to small sample sizes and heterogeneity of outcomes. Therefore, our aim was to perform a systematic review and meta-analyses on NIBS studies assessing the n-back task, which is a reliable index for WM. From the first data available to February 2013, we looked for sham-controlled, randomized studies that used NIBS over the DLPFC using the n-back task in PubMed/MEDLINE and other databases. Twelve studies (describing 33 experiments) matched our eligibility criteria. Active vs. sham NIBS was significantly associated with faster response times (RTs), higher percentage of correct responses and lower percentage of error responses. However, meta-regressions showed that tDCS (vs. rTMS) presented only an improvement in RT, and not in accuracy. This could have occurred in part because almost all tDCS studies employed a crossover design, possibly due to the reliable tDCS blinding. Study design was also associated with no improvement in correct responses in the active vs. sham groups. To conclude, rTMS of the DLPFC significantly improved all measures of WM performance whereas tDCS significantly improved RT, but not the percentage of correct and error responses. Mechanistic insights on the role of DLPFC in WM are further discussed, as well as how NIBS techniques could be used in neuropsychiatric samples presenting WM deficits, such as major depression, dementia and schizophrenia.
Topics: Electric Stimulation; Female; Humans; Male; Memory, Short-Term; Prefrontal Cortex; Transcranial Magnetic Stimulation
PubMed: 24514153
DOI: 10.1016/j.bandc.2014.01.008 -
JAMA Network Open May 2024Noninvasive brain stimulation (NIBS) interventions have been shown to be efficacious in several mental disorders, but the optimal dose stimulation parameters for each... (Meta-Analysis)
Meta-Analysis
IMPORTANCE
Noninvasive brain stimulation (NIBS) interventions have been shown to be efficacious in several mental disorders, but the optimal dose stimulation parameters for each disorder are unknown.
OBJECTIVE
To define NIBS dose stimulation parameters associated with the greatest efficacy in symptom improvement across mental disorders.
DATA SOURCES
Studies were drawn from an updated (to April 30, 2023) previous systematic review based on a search of PubMed, OVID, and Web of Knowledge.
STUDY SELECTION
Randomized clinical trials were selected that tested transcranial magnetic stimulation (TMS) or transcranial direct current stimulation (tDCS) for any mental disorder in adults aged 18 years or older.
DATA EXTRACTION AND SYNTHESIS
Two authors independently extracted the data. A 1-stage dose-response meta-analysis using a random-effects model was performed. Sensitivity analyses were conducted to test robustness of the findings. This study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline.
MAIN OUTCOMES AND MEASURES
The main outcome was the near-maximal effective doses of total pulses received for TMS and total current dose in coulombs for tDCS.
RESULTS
A total of 110 studies with 4820 participants (2659 men [61.4%]; mean [SD] age, 42.3 [8.8] years) were included. The following significant dose-response associations emerged with bell-shaped curves: (1) in schizophrenia, high-frequency (HF) TMS on the left dorsolateral prefrontal cortex (LDLPFC) for negative symptoms (χ2 = 9.35; df = 2; P = .009) and TMS on the left temporoparietal junction for resistant hallucinations (χ2 = 36.52; df = 2; P < .001); (2) in depression, HF-DLPFC TMS (χ2 = 14.49; df = 2; P < .001); (3) in treatment-resistant depression, LDLPFC tDCS (χ2 = 14.56; df = 2; P < .001); and (4) in substance use disorder, LDLPFC tDCS (χ2 = 33.63; df = 2; P < .001). The following significant dose-response associations emerged with plateaued or ascending curves: (1) in depression, low-frequency (LF) TMS on the right DLPFC (RDLPFC) with ascending curve (χ2 = 25.67; df = 2; P = .001); (2) for treatment-resistant depression, LF TMS on the bilateral DLPFC with ascending curve (χ2 = 5.86; df = 2; P = .004); (3) in obsessive-compulsive disorder, LF-RDLPFC TMS with ascending curve (χ2 = 20.65; df = 2; P < .001) and LF TMS on the orbitofrontal cortex with a plateaued curve (χ2 = 15.19; df = 2; P < .001); and (4) in posttraumatic stress disorder, LF-RDLPFC TMS with ascending curve (χ2 = 54.15; df = 2; P < .001). Sensitivity analyses confirmed the main findings.
CONCLUSIONS AND RELEVANCE
The study findings suggest that NIBS yields specific outcomes based on dose parameters across various mental disorders and brain regions. Clinicians should consider these dose parameters when prescribing NIBS. Additional research is needed to prospectively validate the findings in randomized, sham-controlled trials and explore how other parameters contribute to the observed dose-response association.
Topics: Humans; Transcranial Magnetic Stimulation; Transcranial Direct Current Stimulation; Mental Disorders; Adult; Male; Female; Middle Aged; Randomized Controlled Trials as Topic
PubMed: 38776083
DOI: 10.1001/jamanetworkopen.2024.12616 -
Schizophrenia (Heidelberg, Germany) Sep 2023This systematic review aimed to review neuroimaging studies comparing clozapine-resistant schizophrenia patients with clozapine-responding patients, and with first-line... (Review)
Review
This systematic review aimed to review neuroimaging studies comparing clozapine-resistant schizophrenia patients with clozapine-responding patients, and with first-line antipsychotic responding (FLR) patients. A total of 19 studies including 6 longitudinal studies were identified. Imaging techniques comprised computerized tomography (CT, n = 3), structural magnetic resonance imaging (MRI, n = 7), magnetic resonance spectroscopy (MRS, n = 5), functional MRI (n = 1), single-photon emission computerized tomography (SPECT, n = 3) and diffusion tensor imaging (DTI, n = 1). The most consistent finding was hypo-frontality in the clozapine-resistant group compared with the clozapine-responding group with possible differences in frontal-striatal-basal ganglia circuitry as well as the GABA level between the two treatment-resistant groups. Additional statistically significant findings were reported when comparing clozapine-resistant patients with the FLR group, including lower cortical thickness and brain volume of multiple brain regions as well as lower Glx/Cr level in the dorsolateral prefrontal cortex. Both treatment-resistant groups were found to have extensive differences in neurobiological features in comparison with the FLR group. Overall results suggested treatment-resistant schizophrenia is likely to be a neurobiological distinct type of the illness. Clozapine-resistant and clozapine-responding schizophrenia are likely to have both shared and distinct neurobiological features. However, conclusions from existing studies are limited, and future multi-center collaborative studies are required with a consensus clinical definition of patient samples, multimodal imaging tools, and longitudinal study designs.
PubMed: 37752161
DOI: 10.1038/s41537-023-00392-7