Study of the Functional Brain Connectivity and Lower-Limb Motor Imagery Performance After Transcranial Direct Current Stimulation

The use of transcranial direct current stimulation (tDCS) has been related to the improvement of motor and learning tasks. The current research studies the effects of an asymmetric tDCS setup over brain connectivity, when the subject is performing a motor imagery (MI) task during five consecutive days. A brain–computer interface (BCI) based on electroencephalography is simulated in offline analysis to study the effect that tDCS has over different electrode configurations for the BCI. This way, the BCI performance is used as a validation index of the effect of the tDCS setup by the analysis of the classifier accuracy of the experimental sessions. In addition, the relationship between the brain connectivity and the BCI accuracy performance is analyzed. Results indicate that tDCS group, in comparison to the placebo sham group, shows a higher significant number of connectivity interactions in the motor electrodes during MI tasks and an increasing BCI accuracy over the days. However, the asymmetric tDCS setup does not improve the BCI performance of the electrodes in the intended hemisphere.

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Effect of the Interindividual Variability on Computational Modeling of Transcranial Direct Current Stimulation

Computational Intelligence and Neuroscience ◽

10.1155/2015/963293 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 12

Author(s):

Marta Parazzini ◽

Serena Fiocchi ◽

Ilaria Liorni ◽

Paolo Ravazzani

Keyword(s):

Direct Current ◽

Transcranial Direct Current Stimulation ◽

Current Flow ◽

Direct Current Stimulation ◽

Human Models ◽

Flow Through ◽

The Subject ◽

Spontaneous Neuronal Activity ◽

And Gender ◽

The Brain

Transcranial direct current stimulation (tDCS) is a neuromodulatory technique that delivers low intensity, direct current to cortical areas facilitating or inhibiting spontaneous neuronal activity. This paper investigates how normal variations in anatomy may affect the current flow through the brain. This was done by applying electromagnetic computational methods to human models of different age and gender and by comparing the electric field and current density amplitude distributions within the tissues. Results of this study showed that the general trend of the spatial distributions of the field amplitude shares some gross characteristics among the different human models for the same electrode montages. However, the physical dimension of the subject and his/her morphological and anatomical characteristics somehow influence the detailed field distributions such as the field values.

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Anodal Transcranial Direct Current Stimulation Increases Bilateral Directed Brain Connectivity during Motor-Imagery Based Brain-Computer Interface Control

Frontiers in Neuroscience ◽

10.3389/fnins.2017.00691 ◽

2017 ◽

Vol 11 ◽

Cited By ~ 11

Author(s):

Bryan S. Baxter ◽

Bradley J. Edelman ◽

Abbas Sohrabpour ◽

Bin He

Keyword(s):

Motor Imagery ◽

Direct Current ◽

Transcranial Direct Current Stimulation ◽

Brain Connectivity ◽

Brain Computer Interface ◽

Computer Interface ◽

Direct Current Stimulation ◽

Interface Control

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Converging Evidence That Neural Plasticity Underlies Transcranial Direct-Current Stimulation

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_01639 ◽

2021 ◽

Vol 33 (1) ◽

pp. 146-157

Author(s):

Chong Zhao ◽

Geoffrey F. Woodman

Keyword(s):

Visual Search ◽

Direct Current ◽

Neural Plasticity ◽

Transcranial Direct Current Stimulation ◽

Time Course ◽

Memory Task ◽

Long Term Memory ◽

Visual Stream ◽

Direct Current Stimulation ◽

The Brain

It is not definitely known how direct-current stimulation causes its long-lasting effects. Here, we tested the hypothesis that the long time course of transcranial direct-current stimulation (tDCS) is because of the electrical field increasing the plasticity of the brain tissue. If this is the case, then we should see tDCS effects when humans need to encode information into long-term memory, but not at other times. We tested this hypothesis by delivering tDCS to the ventral visual stream of human participants during different tasks (i.e., recognition memory vs. visual search) and at different times during a memory task. We found that tDCS improved memory encoding, and the neural correlates thereof, but not retrieval. We also found that tDCS did not change the efficiency of information processing during visual search for a certain target object, a task that does not require the formation of new connections in the brain but instead relies on attention and object recognition mechanisms. Thus, our findings support the hypothesis that direct-current stimulation modulates brain activity by changing the underlying plasticity of the tissue.

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Transcranial direct current stimulation alters functional network structure in humans

10.1101/296657 ◽

2018 ◽

Author(s):

M. Ruttorf ◽

S. Kristensen ◽

L.R. Schad ◽

J. Almeida

Keyword(s):

Neuronal Activity ◽

Direct Current ◽

Transcranial Direct Current Stimulation ◽

Network Architecture ◽

Functional Magnetic Resonance ◽

Resonance Imaging ◽

Direct Current Stimulation ◽

Brain States ◽

The Relationship ◽

Central Tool

AbstractTranscranial direct current stimulation (tDCS) is routinely used in basic and clinical research, but its efficacy has been challenged on a methodological and statistical basis recently. The arguments against tDCS derive from insufficient understanding of how this technique interacts with brain processes physiologically. Because of its potential as a central tool in neuroscience, it is important to clarify whether and how tDCS affects neuronal activity. Here, we investigate influences of offline tDCS on network architecture measured by functional magnetic resonance imaging. Our results reveal a tDCS-induced reorganisation of a functionally-defined network that is dependent on whether we are exciting or inhibiting a node within this network, confirming in a functioning brain, and in a bias free and independent fashion that tDCS influences neuronal activity. Moreover, our results suggest that network-specific connectivity has an important role in defining the effects of tDCS and the relationship between brain states and behaviour.

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Transcranial direct current stimulation enhances mu rhythm desynchronization during motor imagery that depends on handedness

Laterality Asymmetries of Body Brain and Cognition ◽

10.1080/1357650x.2014.998679 ◽

2015 ◽

Vol 20 (4) ◽

pp. 453-468 ◽

Cited By ~ 7

Author(s):

Shoko Kasuga ◽

Yayoi Matsushika ◽

Yuko Kasashima-Shindo ◽

Daiki Kamatani ◽

Toshiyuki Fujiwara ◽

...

Keyword(s):

Motor Imagery ◽

Direct Current ◽

Transcranial Direct Current Stimulation ◽

Mu Rhythm ◽

Direct Current Stimulation

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Combined brain Fe, Cu, Zn and neurometabolite analysis – a new methodology for unraveling the efficacy of transcranial direct current stimulation (tDCS) in appetite control

Metallomics ◽

10.1039/c7mt00329c ◽

2018 ◽

Vol 10 (3) ◽

pp. 397-405

Author(s):

Agata Ziomber ◽

Artur Dawid Surowka ◽

Lucyna Antkiewicz-Michaluk ◽

Irena Romanska ◽

Pawel Wrobel ◽

...

Keyword(s):

Direct Current ◽

Transcranial Direct Current Stimulation ◽

Appetite Control ◽

Direct Current Stimulation ◽

The Brain

A new methodology for a combined Fe, Cu, Zn and neurometabolite analysis in the brain is reported.

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Working Memory Training and Transcranial Direct Current Stimulation

Cognitive and Working Memory Training ◽

10.1093/oso/9780199974467.003.0006 ◽

2019 ◽

pp. 105-130

Author(s):

Jacky Au ◽

Martin Buschkuehl ◽

Susanne M. Jaeggi

Keyword(s):

Working Memory ◽

Electrical Stimulation ◽

Direct Current ◽

Transcranial Direct Current Stimulation ◽

Working Memory Training ◽

Memory Training ◽

Transcranial Electrical Stimulation ◽

Direct Current Stimulation ◽

Underlying Mechanisms ◽

The Brain

The aim of this chapter is to contribute to the discussion of the cognitive neuroscience of brain stimulation. In doing so, the authors emphasize work from their own laboratory that focuses both on working memory training and transcranial direct current stimulation. Transcranial direct current stimulation is one of the most commonly used and extensively researched methods of transcranial electrical stimulation. The chapter focuses on implementation of transcranial direct current stimulation to enhance and inform research on working memory training, and not on the underlying mechanisms of transcranial direct current stimulation. Thus, while respecting the intricacies and unknowns of the inner workings of electrical stimulation on the brain, the chapter relies on the premise that transcranial direct current stimulation is able to directly affect the electrophysiological profile of the brain and provides evidence that this in turn can influence behavior given the right parameters.

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