Transcranial direct current stimulation(tDCS)is a promising method for altering cortical excitability with clinical implications.It has been increasingly used in neurodevelopmental disorders,especially attention-defic...Transcranial direct current stimulation(tDCS)is a promising method for altering cortical excitability with clinical implications.It has been increasingly used in neurodevelopmental disorders,especially attention-deficit hyperactivity disorder(ADHD),but its efficacy(based on effect size calculations),safety,and stimulation parameters have not been systematically examined.In this systematic review,we aimed to(1)explore the effectiveness of tDCS on the clinical symptoms and neuropsychological deficits of ADHD patients,(2)evaluate the safety of tDCS application,especially in children with ADHD,(3)model the electrical field intensity in the target regions based on the commonly-applied and effective versus less-effective protocols,and(4)discuss and propose advanced tDCS parameters.Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses approach,a literature search identified 14 empirical experiments investigating tDCS effects in ADHD.Partial improving effects of tDCS on cognitive deficits(response inhibition,working memory,attention,and cognitive flexibility)or clinical symptoms(e.g.,impulsivity and inattention)are reported in10 studies.No serious adverse effects are reported in 747 sessions of tDCS.The left and right dorsolateral prefrontal cortex are the regions most often targeted,and anodal tDCS the protocol most often applied.An intensity of 2 mA induced stronger electrical fields than 1 mA in adults with ADHD and was associated with significant behavioral changes.In ADHD children,however,the electrical field induced by 1 mA,which is likely larger than the electrical field induced by 1 mA in adults due to the smaller head size of children,was sufficient to result in significant behavioral change.Overall,tDCS seems to be a promising method for improving ADHD deficits.However,the clinical utility of tDCS in ADHD cannot yet be concluded and requires further systematic investigation in larger sample sizes.Cortical regions involved in ADHD pathophysiology,stimulation parameters(e.g.intensity,duration,polarity,and electrode size),and types of symptom/deficit are potential determinants of tDCS efficacy in ADHD.Developmental aspects of tDCS in childhood ADHD should be considered as well.展开更多
Background:Gait problems are an important symptom in Parkinson’s disease(PD),a progressive neurodegenerative disease.Transcranial direct current stimulation(tDCS)is a neuromodulatory intervention that can modulate co...Background:Gait problems are an important symptom in Parkinson’s disease(PD),a progressive neurodegenerative disease.Transcranial direct current stimulation(tDCS)is a neuromodulatory intervention that can modulate cortical excitability of the gait-related regions.Despite an increasing number of gait-related tDCS studies in PD,the efficacy of this technique for improving gait has not been systematically investigated yet.Here,we aimed to systematically explore the effects of tDCS on gait in PD,based on available experimental studies.Methods:Using the PRISMA(Preferred Reporting Items for Systematic Reviews and Meta-Analyses)approach,PubMed,Web of Science,Scopus,and PEDro databases were searched for randomized clinical trials assessing the effect of tDCS on gait in patients with PD.Results:Eighteen studies were included in this systematic review.Overall,tDCS targeting the motor cortex and supplementary motor area bilaterally seems to be promising for gait rehabilitation in PD.Studies of tDCS targeting the dorosolateral prefrontal cortex or cerebellum showed more heterogeneous results.More studies are needed to systematically compare the efficacy of different tDCS protocols,including protocols applying tDCS alone and/or in combination with conventional gait rehabilitation treatment in PD.Conclusions:tDCS is a promising intervention approach to improving gait in PD.Anodal tDCS over the motor areas has shown a positive effect on gait,but stimulation of other areas is less promising.However,the heterogeneities of methods and results have made it difficult to draw firm conclusions.Therefore,systematic explorations of tDCS protocols are required to optimize the efficacy.展开更多
基金This review was supported by the Department of Psychology and Neurosciences,Leibniz-Institut fiir Arbeitsforschung Ministry of Science,Research and Technology,Deputy of Scholarship and Students Affairs,Iran(95000171)the German Ministry of Research and Education(German Center for Brain Stimulation grant number 01EE1403C).
文摘Transcranial direct current stimulation(tDCS)is a promising method for altering cortical excitability with clinical implications.It has been increasingly used in neurodevelopmental disorders,especially attention-deficit hyperactivity disorder(ADHD),but its efficacy(based on effect size calculations),safety,and stimulation parameters have not been systematically examined.In this systematic review,we aimed to(1)explore the effectiveness of tDCS on the clinical symptoms and neuropsychological deficits of ADHD patients,(2)evaluate the safety of tDCS application,especially in children with ADHD,(3)model the electrical field intensity in the target regions based on the commonly-applied and effective versus less-effective protocols,and(4)discuss and propose advanced tDCS parameters.Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses approach,a literature search identified 14 empirical experiments investigating tDCS effects in ADHD.Partial improving effects of tDCS on cognitive deficits(response inhibition,working memory,attention,and cognitive flexibility)or clinical symptoms(e.g.,impulsivity and inattention)are reported in10 studies.No serious adverse effects are reported in 747 sessions of tDCS.The left and right dorsolateral prefrontal cortex are the regions most often targeted,and anodal tDCS the protocol most often applied.An intensity of 2 mA induced stronger electrical fields than 1 mA in adults with ADHD and was associated with significant behavioral changes.In ADHD children,however,the electrical field induced by 1 mA,which is likely larger than the electrical field induced by 1 mA in adults due to the smaller head size of children,was sufficient to result in significant behavioral change.Overall,tDCS seems to be a promising method for improving ADHD deficits.However,the clinical utility of tDCS in ADHD cannot yet be concluded and requires further systematic investigation in larger sample sizes.Cortical regions involved in ADHD pathophysiology,stimulation parameters(e.g.intensity,duration,polarity,and electrode size),and types of symptom/deficit are potential determinants of tDCS efficacy in ADHD.Developmental aspects of tDCS in childhood ADHD should be considered as well.
基金This work was supported by the Musculoskeletal Research Center,Isfahan University of Medical Sciences,Isfahan,Iran.
文摘Background:Gait problems are an important symptom in Parkinson’s disease(PD),a progressive neurodegenerative disease.Transcranial direct current stimulation(tDCS)is a neuromodulatory intervention that can modulate cortical excitability of the gait-related regions.Despite an increasing number of gait-related tDCS studies in PD,the efficacy of this technique for improving gait has not been systematically investigated yet.Here,we aimed to systematically explore the effects of tDCS on gait in PD,based on available experimental studies.Methods:Using the PRISMA(Preferred Reporting Items for Systematic Reviews and Meta-Analyses)approach,PubMed,Web of Science,Scopus,and PEDro databases were searched for randomized clinical trials assessing the effect of tDCS on gait in patients with PD.Results:Eighteen studies were included in this systematic review.Overall,tDCS targeting the motor cortex and supplementary motor area bilaterally seems to be promising for gait rehabilitation in PD.Studies of tDCS targeting the dorosolateral prefrontal cortex or cerebellum showed more heterogeneous results.More studies are needed to systematically compare the efficacy of different tDCS protocols,including protocols applying tDCS alone and/or in combination with conventional gait rehabilitation treatment in PD.Conclusions:tDCS is a promising intervention approach to improving gait in PD.Anodal tDCS over the motor areas has shown a positive effect on gait,but stimulation of other areas is less promising.However,the heterogeneities of methods and results have made it difficult to draw firm conclusions.Therefore,systematic explorations of tDCS protocols are required to optimize the efficacy.
