Effects of Anodal Transcranial Direct Current Stimulation (tDCS) Preconditioning Combined with Arachydonilcyclopropylamide (ACPA) on Exploratory Locomotion in Male Mice

Background: When confronting with an unfamiliar environment, animals exert orderly and complex behaviors called exploration. Locomotion is the most important part of exploratory behavior, but the principles of this behavior have not been fully understood yet. Here we studied the effects of the frontal region preconditioning with right and left frontal anodal transcranial direct current stimulation (tDCS) combined with the cannabinoid CB1 receptor agonist, arachydonilcyclopropylamide (ACPA) on locomotion in NMRI male mice. Materials and Methods: This study was carried out with 12 groups of NMRI mice (each group consisted of 8 mice), which were divided into 3 categories of ACPA alone, right, and left frontal anodal tDCS combined with ACPA. Anodal tDCS (with a current intensity of 0.2 mA for 20 minutes) was performed one day prior to ACPA intraperitoneal injection (0.01,0.05,0.1 mg/kg) and 15 minutes after injection the exploratory locomotion test was carried out. Results: The data showed that right frontal anodal tDCS combined with 0.01 and 0.05 mg/kg of ACPA and left frontal anodal tDCS combined with 0.05 mg/kg ACPA increased exploratory locomotion. Conclusions: Our finding suggested that combined implementation of right and left anodal tDCS and ACPA exerted anxiolytic properties and could increase exploratory related locomotion.[GMJ. 2016;5(4):173-79]

Download Full-text

Effect of Different Intensities of Transcranial Direct Current Stimulation on Postural Response to External Perturbation in Patients With Parkinson’s Disease

Neurorehabilitation and Neural Repair ◽

10.1177/1545968320962513 ◽

2020 ◽

Vol 34 (11) ◽

pp. 1009-1019

Author(s):

Victor Spiandor Beretta ◽

Rodrigo Vitório ◽

Priscila Nóbrega-Sousa ◽

Núbia Ribeiro Conceição ◽

Diego Orcioli-Silva ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Direct Current ◽

Transcranial Direct Current Stimulation ◽

External Perturbation ◽

Cortical Activity ◽

Anodal Tdcs ◽

Postural Response ◽

Direct Current Stimulation ◽

Sham Condition

Background Habituation of postural response to perturbations is impaired in people with Parkinson’s disease (PD) due to deficits in cortico-basal pathways. Although transcranial direct current stimulation (tDCS) modulate cortico-basal networks, it remains unclear if it can benefit postural control in PD. Objective To analyze the effect of different intensities of anodal tDCS on postural responses and prefrontal cortex (PFC) activity during the habituation to the external perturbation in patients with PD (n = 24). Methods Anodal tDCS was applied over the primary motor cortex (M1) with 1 mA, 2 mA, and sham stimulation in 3 different sessions (~2 weeks apart) during 20 minutes immediately before the postural assessment. External perturbation (7 trials) was applied by a support base posterior translation (20 cm/s and 5 cm). Primary outcome measures included lower limb electromyography and center of pressure parameters. Measures of PFC activity are reported as exploratory outcomes. Analyses of variance (Stimulation Condition × Trial) were performed. Results Habituation of perturbation was evidenced independent of the stimulation conditions. Both active stimulation intensities had shorter recovery time and a trend for lower cortical activity in the stimulated hemisphere when compared to sham condition. Shorter onset latency of the medial gastrocnemius as well as lower cortical activity in the nonstimulated hemisphere were only observed after 2 mA concerning the sham condition. Conclusions tDCS over M1 improved the postural response to external perturbation in PD, with better response observed for 2 mA compared with 1 mA. However, tDCS seems to be inefficient in modifying the habituation of perturbation.

Download Full-text

Transcranial Direct Current Stimulation (tDCS) in Unilateral Cerebral Palsy: A Pilot Study of Motor Effect

Neural Plasticity ◽

10.1155/2019/2184398 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10 ◽

Cited By ~ 3

Author(s):

Emanuela Inguaggiato ◽

Nadia Bolognini ◽

Simona Fiori ◽

Giovanni Cioni

Keyword(s):

Cerebral Palsy ◽

Pilot Study ◽

Upper Limb ◽

Direct Current ◽

Transcranial Direct Current Stimulation ◽

Primary Motor Cortex ◽

Controlled Study ◽

Anodal Tdcs ◽

Direct Current Stimulation ◽

Unilateral Cerebral Palsy

Transcranial Direct Current Stimulation (tDCS) is an emerging tool to improve upper limb motor functions after stroke acquired in adulthood; however, there is a paucity of reports on its efficacy for upper limb motor rehabilitation in congenital or early-acquired stroke. In this pilot study we have explored, for the first time, the immediate effects, and their short-term persistence, of a single application of anodal tDCS on chronic upper limb motor disorders in children and young individuals with Unilateral Cerebral Palsy (UCP). To this aim, in a crossover sham-controlled study, eight subjects aged 10-28 years with UCP underwent two sessions of active and sham tDCS. Anodal tDCS (1.5 mA, 20 min) was delivered over the primary motor cortex (M1) of the ipsilesional hemisphere. Results showed, only following the active stimulation, an immediate improvement in unimanual gross motor dexterity of hemiplegic, but not of nonhemiplegic, hand in Box and Block test (BBT). Such improvement remained stable for at least 90 minutes. Performance of both hands in Hand Grip Strength test was not modified by anodal tDCS. Improvement in BBT was unrelated to participants’ age or lesion size, as revealed by MRI data analysis. No serious adverse effects occurred after tDCS; some mild and transient side effects (e.g., headache, tingling, and itchiness) were reported in a limited number of cases. This study provides an innovative contribution to scientific literature on the efficacy and safety of anodal tDCS in UCP. This trial is registered with NCT03137940.

Download Full-text

Effects of Transcranial Direct Current Stimulation over Left Dorsolateral pFC on the Attentional Blink Depend on Individual Baseline Performance

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00867 ◽

2015 ◽

Vol 27 (12) ◽

pp. 2382-2393 ◽

Cited By ~ 18

Author(s):

Raquel E. London ◽

Heleen A. Slagter

Keyword(s):

Working Memory ◽

Individual Differences ◽

Attentional Blink ◽

Direct Current ◽

Transcranial Direct Current Stimulation ◽

Critical Role ◽

Anodal Tdcs ◽

Direct Current Stimulation ◽

Cathodal Tdcs ◽

Left Dlpfc

Selection mechanisms that dynamically gate only relevant perceptual information for further processing and sustained representation in working memory are critical for goal-directed behavior. We examined whether this gating process can be modulated by anodal transcranial direct current stimulation (tDCS) over left dorsolateral pFC (DLPFC)—a region known to play a key role in working memory and conscious access. Specifically, we examined the effects of tDCS on the magnitude of the so-called “attentional blink” (AB), a deficit in identifying the second of two targets presented in rapid succession. Thirty-four participants performed a standard AB task before (baseline), during, and after 20 min of 1-mA anodal and cathodal tDCS in two separate sessions. On the basis of previous reports linking individual differences in AB magnitude to individual differences in DLPFC activity and on suggestions that effects of tDCS depend on baseline brain activity levels, we hypothesized that anodal tDCS over left DLPFC would modulate the magnitude of the AB as a function of individual baseline AB magnitude. Indeed, individual differences analyses revealed that anodal tDCS decreased the AB in participants with a large baseline AB but increased the AB in participants with a small baseline AB. This effect was only observed during (but not after) stimulation, was not found for cathodal tDCS, and could not be explained by regression to the mean. Notably, the effects of tDCS were not apparent at the group level, highlighting the importance of taking individual variability in performance into account when evaluating the effectiveness of tDCS. These findings support the idea that left DLPFC plays a critical role in the AB and in conscious access more generally. They are also in line with the notion that there is an optimal level of prefrontal activity for cognitive function, with both too little and too much activity hurting performance.

Download Full-text

Anodal transcranial direct current stimulation of the motor cortex induces opposite modulation of reciprocal inhibition in wrist extensor and flexor

Journal of Neurophysiology ◽

10.1152/jn.00249.2013 ◽

2014 ◽

Vol 112 (6) ◽

pp. 1505-1515 ◽

Cited By ~ 9

Author(s):

Alexandra Lackmy-Vallée ◽

Wanalee Klomjai ◽

Bernard Bussel ◽

Rose Katz ◽

Nicolas Roche

Keyword(s):

Motor Cortex ◽

Direct Current ◽

Transcranial Direct Current Stimulation ◽

Reciprocal Inhibition ◽

Anodal Tdcs ◽

Direct Current Stimulation ◽

Wrist Extensor ◽

Hand Motor Area ◽

Opposing Effects ◽

Wrist Flexors

Transcranial direct current stimulation (tDCS) is used as a noninvasive tool to modulate brain excitability in humans. Recently, several studies have demonstrated that tDCS applied over the motor cortex also modulates spinal neural network excitability and therefore can be used to explore the corticospinal control acting on spinal neurons. Previously, we showed that reciprocal inhibition directed to wrist flexor motoneurons is enhanced during contralateral anodal tDCS, but it is likely that the corticospinal control acting on spinal networks controlling wrist flexors and extensors is not similar. The primary aim of the study was to explore the effects of anodal tDCS on reciprocal inhibition directed to wrist extensor motoneurons. To further examine the supraspinal control acting on the reciprocal inhibition between wrist flexors and extensors, we also explored the effects of the tDCS applied to the ipsilateral hand motor area. In healthy volunteers, we tested the effects induced by sham and anodal tDCS on reciprocal inhibition pathways innervating wrist muscles. Reciprocal inhibition directed from flexor to extensor muscles and the reverse situation, i.e., reciprocal inhibition, directed from extensors to flexors were studied in parallel with the H reflex technique. Our main finding was that contralateral anodal tDCS induces opposing effects on reciprocal inhibition: it decreases reciprocal inhibition directed from flexors to extensors, but it increases reciprocal inhibition directed from extensors to flexors. The functional result of these opposite effects on reciprocal inhibition seems to favor wrist extension excitability, suggesting an asymmetric descending control onto the interneurons that mediate reciprocal inhibition.

Download Full-text

Effects of Transcranial Direct Current Stimulation on GABA and Glutamate in Children: A Pilot Study

10.1101/759290 ◽

2019 ◽

Author(s):

C Nwaroh ◽

A Giuffre ◽

L Cole ◽

T Bell ◽

H. L. Carlson ◽

...

Keyword(s):

Skill Acquisition ◽

Direct Current ◽

Sensorimotor Cortex ◽

Transcranial Direct Current Stimulation ◽

Primary Motor Cortex ◽

Therapeutic Potential ◽

Fine Motor ◽

Resonance Spectroscopy ◽

Anodal Tdcs ◽

Direct Current Stimulation

AbstractTranscranial direct current stimulation (tDCS) is a form of non-invasive brain stimulation that safely modulates brain excitability and has therapeutic potential for many conditions. Several studies have shown that anodal tDCS of the primary motor cortex (M1) facilitates motor learning and plasticity, but there is little information about the underlying mechanisms. Using magnetic resonance spectroscopy (MRS) it has been shown that tDCS can affect local levels of γ-aminobutyric acid (GABA) and Glx (a measure of glutamate and glutamine combined) in adults, both of which are known to be associated with skill acquisition and plasticity; however this has yet to be studied in children and adolescents. This study examined GABA and Glx in response to conventional anodal tDCS (a-tDCS) and high definition tDCS (HD-tDCS) targeting the M1 in a pediatric population. Twenty-four typically developing, right handed children ages 12–18 years participated in five consecutive days of tDCS intervention (sham, a-tDCS or HD-tDCS) targeting the right M1 while training in a fine motor task (Purdue Pegboard Task) with their left hand. Glutamate and GABA were measured before and after the protocol (at day 5 and 6 weeks) using conventional MRS and GABA-edited MRS in the sensorimotor cortices. Glutamate measured in the left sensorimotor cortex was higher in the HD-tDCS group compared to a-tDCS and sham at 6 weeks (p = 0.001). No changes in GABA were observed in either sensorimotor cortex at any time. These results suggest that neither a-tDCS or HD-tDCS locally affect GABA and glutamate in the developing brain and therefore it may demonstrate different responses in adults.

Download Full-text

Investigation of the effect of Delayed Auditory Feedback and transcranial Direct Current Stimulation (DAF-tDCS) treatment for the enhancement of speech fluency in adults who stutter: a Randomized Controlled Trial

10.21203/rs.3.rs-29391/v1 ◽

2020 ◽

Author(s):

Narges Moein ◽

Reyhane Mohamadi ◽

Reza Rostami ◽

Michael Nitsche ◽

Reza Zomorrodi ◽

...

Keyword(s):

Direct Current ◽

Transcranial Direct Current Stimulation ◽

Auditory Feedback ◽

Intervention Group ◽

Control Group ◽

Anodal Tdcs ◽

Delayed Auditory Feedback ◽

Direct Current Stimulation ◽

Speech Fluency ◽

Adults Who Stutter

Abstract Background: With a population prevalence of one percent, stuttering is among the main speech pathology-related topics of research. Adults who stutter may benefit from transcranial direct current stimulation (tDCS) as an adjunctive intervention for enhancing speech fluency. In this study, Delayed Auditory Feedback (DAF) was combined with tDCS applied over the superior temporal gyrus. It was anticipated that intervention caused improvements of speech fluency become more stable.Methods: A randomized, double-blind, sham-controlled clinical trial was conducted to investigate the effectiveness of intervention in enhancing speech fluency. Fifty participants were randomly allocated the intervention or control group. In the intervention group, participants received DAF combined with anodal tDCS, while the control group was exposed to sham tDCS simultaneously with DAF. Each subject participated in six intervention sessions. Speech fluency was assessed before intervention as baseline, as well as immediately, one week and six weeks after intervention.Results: In the intervention group, the percentage of stuttered syllables was significantly reduced immediately, one week and six weeks after the intervention, as compared with the control group. The scores of the Stuttering Severity Instrument, also showed a significant reduction in the intervention group compared with the control group. No significant difference was found in the Overall Assessment of the Speaker’s Experience of Stuttering questionnaire scores between the two patient two groups after intervention.Conclusion: The results of this study propose anodal tDCS as an adjunctive method to increase speech fluency in stuttering for a prolonged time course after intervention, when combined with fluency therapy.Trial registration: This trial was registered in ClinicalTrial.gov before recruiting the subjects. The registration number is NCT03990168 and the date of registration is June 18, 2019. https://clinicaltrials.gov/ct2/show/NCT03990168

Download Full-text

Treadmill training combined with transcranial direct current stimulation over the primary motor cortex in a child with cerebral palsy and hydrocephalus: A case report.

Manual Therapy Posturology & Rehabilitation Journal ◽

10.17784/mtprehabjournal.2014.12.210 ◽

2014 ◽

Vol 12 ◽

pp. 210

Author(s):

Fernanda Lobo Rezende ◽

Natália De Almeida Carvalho Duarte ◽

Luanda André Collange Grecco ◽

Claudia Santos Oliveira

Keyword(s):

Cerebral Palsy ◽

Motor Cortex ◽

Direct Current ◽

Transcranial Direct Current Stimulation ◽

Primary Motor Cortex ◽

Treadmill Training ◽

Anodal Tdcs ◽

Direct Current Stimulation ◽

Eyes Closed ◽

Intervention Protocol

Introduction: Transcranial direct current stimulation (tDCS) is a promising technique that stimulates the cortex with a direct, low-intensity electric current and can potentiate motor learning. Objective: Describe the results of an intervention protocol involving anodal stimulation over the primary motor cortex combined with treadmill training in a child with cerebral palsy. Method: The intervention was comprised of ten sessions of anodal tDCS (1mA) over the primary motor cortex during the treadmill training. Stabilometric analysis was evaluated one week before and one week after the intervention. Results: A reduction in oscillations of the COP was found under both conditions (eyes opened and eyes closed. Conclusion: Our findings suggest that anodal tDCS over primary motor cortex can potentiate the results of treadmill training.

Download Full-text

Effect of conventional transcranial direct current stimulation devices and electrode sizes on motor cortical excitability of the quadriceps muscle

Restorative Neurology and Neuroscience ◽

10.3233/rnn-211210 ◽

2021 ◽

pp. 1-13

Author(s):

Adam Z. Gardi ◽

Amanda K. Vogel ◽

Aastha K. Dharia ◽

Chandramouli Krishnan

Keyword(s):

Direct Current ◽

Transcranial Direct Current Stimulation ◽

Cortical Excitability ◽

Null Model ◽

Interaction Effects ◽

Anodal Tdcs ◽

Electrode Size ◽

Direct Current Stimulation ◽

Motor Cortical Excitability ◽

Motor Cortical

Background: There is a growing concern among the scientific community that the effects of transcranial direct current stimulation (tDCS) are highly variable across studies. The use of different tDCS devices and electrode sizes may contribute to this variability; however, this issue has not been verified experimentally. Objective: To evaluate the effects of tDCS device and electrode size on quadriceps motor cortical excitability. Methods: The effect of tDCS device and electrode size on quadriceps motor cortical excitability was quantified across a range of TMS intensities using a novel evoked torque approach that has been previously shown to be highly reliable. In experiment 1, anodal tDCS-induced excitability changes were measured in twenty individuals using two devices (Empi and Soterix) on two separate days. In experiment 2, anodal tDCS-induced excitability changes were measured in thirty individuals divided into three groups based on the electrode size. A novel Bayesian approach was used in addition to the classical hypothesis testing during data analyses. Results: There were no significant main or interaction effects, indicating that cortical excitability did not differ between different tDCS devices or electrode sizes. The lack of pre-post time effect in both experiments indicated that cortical excitability was minimally affected by anodal tDCS. Bayesian analyses indicated that the null model was more favored than the main or the interaction effects model. Conclusions: Motor cortical excitability was not altered by anodal tDCS and did not differ by devices or electrode sizes used in the study. Future studies should examine if behavioral outcomes are different based on tDCS device or electrode size.

Download Full-text

Efficiency of Repetitive Transcranial Direct Current Stimulation of the Dorsolateral Prefrontal Cortex in Disorders of Consciousness: A Randomized Sham-Controlled Study

Neural Plasticity ◽

10.1155/2019/7089543 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11 ◽

Cited By ~ 3

Author(s):

Min Wu ◽

Yamei Yu ◽

Lunjie Luo ◽

Yuehao Wu ◽

Jian Gao ◽

...

Keyword(s):

Prefrontal Cortex ◽

Direct Current ◽

Transcranial Direct Current Stimulation ◽

Dorsolateral Prefrontal Cortex ◽

Disorders Of Consciousness ◽

Anodal Tdcs ◽

Direct Current Stimulation ◽

Dorsolateral Prefrontal ◽

The Right ◽

Stimulation Of

Conventional transcranial direct current stimulation (tDCS) targeting the left dorsolateral prefrontal cortex (DLPFC) could improve arousal in disorders of consciousness (DOC). However, the comparative effectiveness of anodal stimulation of the left DLPFC and the electrophysiological effect of tDCS are yet to be determined. In this randomized sham-controlled design, patients were separated into three groups (left/right anodal tDCS, sham). Data on the clinical assessments and EEG were collected at baseline and after 2 weeks of tDCS. The outcome at 3-month follow-up was evaluated using the Glasgow Outcome Scale-Extended. Results showed that sessions of the left tDCS facilitated the excitability of the prefrontal cortex, whereas only one patient had a positive outcome. Targeting the right DLPFC was less effective, merely leading to activation of the stimulation site, with no effect on the state of arousal. Moreover, sham stimulation had minimal or no effect on any of the outcomes. These results provide evidence for a hemispheric asymmetry of tDCS effects in patients with DOC. Left anodal tDCS might be more effective for modulating cortical excitability compared to tDCS on the right DLPFC. However, future studies with large sample sizes are needed to confirm these findings. This trial is registered with NCT03809936.

Download Full-text

Transcranial direct current stimulation effects on I-wave activity in humans

Journal of Neurophysiology ◽

10.1152/jn.00617.2010 ◽

2011 ◽

Vol 105 (6) ◽

pp. 2802-2810 ◽

Cited By ~ 40

Author(s):

Nicolas Lang ◽

Michael A. Nitsche ◽

Michele Dileone ◽

Paolo Mazzone ◽

Javier De Andrés-Arés ◽

...

Keyword(s):

Motor Cortex ◽

Direct Current ◽

Transcranial Direct Current Stimulation ◽

Cortical Neurons ◽

Primary Motor Cortex ◽

Motor Evoked Potential ◽

Anodal Tdcs ◽

Direct Current Stimulation ◽

Cathodal Tdcs ◽

Motor Cortex Excitability

Transcranial direct current stimulation (tDCS) of the human cerebral cortex modulates cortical excitability noninvasively in a polarity-specific manner: anodal tDCS leads to lasting facilitation and cathodal tDCS to inhibition of motor cortex excitability. To further elucidate the underlying physiological mechanisms, we recorded corticospinal volleys evoked by single-pulse transcranial magnetic stimulation of the primary motor cortex before and after a 5-min period of anodal or cathodal tDCS in eight conscious patients who had electrodes implanted in the cervical epidural space for the control of pain. The effects of anodal tDCS were evaluated in six subjects and the effects of cathodal tDCS in five subjects. Three subjects were studied with both polarities. Anodal tDCS increased the excitability of cortical circuits generating I waves in the corticospinal system, including the earliest wave (I1 wave), whereas cathodal tDCS suppressed later I waves. The motor evoked potential (MEP) amplitude changes immediately following tDCS periods were in agreement with the effects produced on intracortical circuitry. The results deliver additional evidence that tDCS changes the excitability of cortical neurons.

Download Full-text