This study was supported by the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (2015M3C7A1064832, 2015M3C7A1028373, 2018M3A6A3058651) and by the National Institutes of Health (NIHNIMH 1R01MH111896, NIH-NINDS 1R01NS101362).

All experimental procedures presented in this protocol have been approved by the Institutional Review Board and are in accordance with the Declaration of Helsinki.
1. Research Participants
<ol>
	<li>Recruit individuals who report that they play online games (the gamer group) and those who report that they do not play online games (the non-gamer group). 
	NOTE: Here, we included individuals with two or more IGD symptoms according to the Diagnostic and Statistical Manual of Mental Disorders-523 or those who play games at least one hour per day on average in the gamer group. The non-gamer group undergoes only baseline brain FDG-PET scans to compare rCMRglu with the gamer group and does not receive tDCS sessions.</li>
	<li>For both groups, exclude individuals with (a) major medical, psychiatric, or neurological disorders, (b) history of traumatic brain injury, (c) history of alcohol or other substance abuse or dependence, (d) use of psychotropic medications, or (e) any contraindications for tDCS such as severe headache, metal in the head, history of seizure, epilepsy, or brain surgery, or any lesions or other medical problems on the skin where tDCS electrodes will be attached.</li>
	<li>Explain to each participant the aim of the study, the main experimental procedures, and any potential risks associated with participating in the study. After answering any questions, obtain written consent.</li>
</ol>
2. Baseline Assessment
<ol>
	<li>Evaluate clinical characteristics using the following questionnaires: Internet Addiction Test (IAT)24 and Brief Self Control Scale (BSCS)25. In addition, ask participants to report average weekly hours spent playing games. 
	NOTE: The word &#34;Internet&#34; in the IAT is replaced with &#34;online games&#34; to assess severity of online game addiction.</li>
	<li>Perform brain FDG-PET scans.
	<ol>
		<li>Inject participants with 185 - 222 MBq of FDG and have participants rest for 45 min of an uptake period during which they are awake and resting in supine position in a dark and quiet room with their eyes closed.</li>
		<li>Conduct brain FDG-PET scans to acquire transaxial emission images and CT images using a PET-CT scanner in about 15 min. Apply attenuation correction, standard filtering, and standard reconstruction techniques.</li>
	</ol>
	</li>
</ol>
3. Application of tDCS
<ol>
	<li>Within a week after the baseline assessment, apply tDCS to participants. Prepare tDCS sessions with following materials: a tDCS device, wet wipes, saline solution, two sponge electrodes (6 cm in diameter), a cable, a headcap, and a headband.</li>
	<li>Have the participant sit on a chair.</li>
	<li>Set the stimulation parameters for the tDCS device: 2 mA for 30 min (current density = 0.07 mA/cm2). Set the current so it ramps up to 2.0 mA over 30 s, remains at 2.0 mA for 29 min, and ramps down to 0 mA over the last 30 s.</li>
	<li>Put the headcap (the International 10-20 system) on the participant&#8217;s head and mark the left dorsolateral prefrontal cortex (F3) and the right dorsolateral prefrontal cortex (F4). Then, remove the headcap from the participant&#39;s head.</li>
	<li>Place two sponge electrodes in the rubber holders of the headband and soak them with saline solution.</li>
	<li>Remove any makeup, dirt, or sweat on the scalp where the electrodes will be applied.</li>
	<li>Place the headband over the marking points by putting the anodal electrode over the left DLPFC and the cathodal electrode over the right DLPFC.</li>
	<li>Connect the electrodes to the tDCS device using the cable and turn on the device.</li>
	<li>Ask the participant to report any adverse effects during or after the tDCS session.</li>
	<li>At the end of the 30 min of stimulation, turn off the device and remove the electrodes from the participant.</li>
	<li>Administer a total of 12 tDCS sessions (3 times per week for 4 weeks).</li>
</ol>
4. Follow-up Assessment
<ol>
	<li>Perform the follow-up assessment within a week after the last tDCS session using the same protocol as the baseline assessment.</li>
</ol>
5. Data Analysis
<ol>
	<li>Use an appropriate software package to preprocess the PET images (e.g., Statistical Parametric Mapping 12).
	<ol>
		<li>Convert DICOM files to NIFTI files.</li>
		<li>Spatially normalize all PET images to the standard PET template.</li>
	</ol>
	</li>
	<li>Create binary masks for the left and right DLPFC (e.g., WFU PickAtlas toolbox). The DLPFC is defined by the middle frontal gyrus in the Automated Anatomical Labeling atlas.</li>
	<li>Extract rCMRglu of the left and right DLPFC using the masks (e.g., MarsBaR toolbox). The rCMRglu is normalized to global mean uptake using proportional scaling.</li>
	<li>Calculate asymmetry index (AI) of rCMRglu in the DLPFC as (rCMRglu right - rCMRglu left) / [(rCMRglu right + rCMRglu left) / 2] &#215; 100. Positive AI indicates right-greater-than-left asymmetry of glucose metabolism.</li>
</ol>

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The City University of New York (CUNY) has IP on neurostimulation system and methods with Marom Bikson as inventor. Marom Bikson has equity in Soterix Medical Inc and serves as a consultant for Boston Scientific Inc. All other authors declare no financial conflicts of interest.

We have presented a tDCS and neuroimaging protocol for online gamers and assessed its feasibility. The results demonstrated that repeated sessions of tDCS over the DLPFC reduced online game addiction symptoms and average time spent on games and increased self-control. An increase in self-control was correlated with a decrease in addiction symptoms. Moreover, the abnormal asymmetry of rCMRglu in the DLPFC where the right side was greater than the left side was improved after the tDCS sessions in the gamer group. These res...

In recent years, increasing attention has been paid to excessive online game use since its associations with negative impact on mental health and daily functioning as well as with internet gaming disorder (IGD) have been reported1,2,3. Although several treatment strategies including pharmacotherapy and cognitive-behavioral therapy have been evaluated, evidence for their effectiveness is limited4.
Previous studies have suggested that IGD may share clinical and neurobiological similarities with other behavioral addictions and substance use disorders5,6. It has been reported that the dorsolateral prefrontal cortex (DLPFC) is closely involved in the pathophysiology of substance and behavioral addiction such as craving7, impulse control8, decision making9, and cognitive flexibility10. Several neuroimaging studies on IGD have reported structural and functional impairments in the DLPFC6. In particular, structural neuroimaging studies revealed a reduction in gray matter density in the DLPFC11,12 and a functional magnetic resonance imaging (fMRI) study found an altered cued-induced activity in the DLPFC of patients with IGD13. In addition, functional asymmetry of the brain may contribute to impulsivity and craving in addictions including IGD. For instance, cue-induced craving for online gaming could be related to right prefrontal activations14. However, alterations of regional cerebral metabolic rate of glucose (rCMRglu) associated with excessive online game use or IGD remain to be further investigated compared to other brain deficits15.
Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique that applies a weak electric current (1-2 mA) through electrodes attached to the scalp to modulate neuronal membrane potentials. Generally, the cortical excitability is increased under the anode electrode and decreased under the cathode electrode16. tDCS has become a popular method because it is simple, inexpensive, and safe to administer compared to other brain stimulation techniques such as transcranial magnetic stimulation (TMS) that uses a magnetic pulse to generate an electrical current in the brain tissue under the coil. According to a recent review, the use of conventional tDCS protocols has not produced any serious adverse effects or irreversible injury and is associated with only mild and transient itching or tingling sensation under the stimulation area17.
Several studies have demonstrated favorable results of tDCS18,19,20 and repetitive TMS21,22 over the DLPFC for treating behavioral and substance addiction. However, further studies are needed to investigate the effects of brain stimulation techniques on online game use and the underlying brain changes.
The aim of this study is to present a protocol for applying repeated sessions of tDCS over the DLPFC and neuroimaging to examine the underlying neural correlates in gamers using 18F-&#64258;uoro-2-deoxyglucose positron emission tomography (FDG-PET), as well as to assess its feasibility. Specifically, we focused on changes in addiction symptoms, average time spent on games, self-control, and asymmetry of rCMRglu in the DLPFC.

<table><tbody><tr><td>Discovery STE PET/CT Imaging System</td><td>GE Healthcare</td><td></td><td></td></tr><tr><td>MarsBaR region of interest toolbox for SPM</td><td>Matthew Brett</td><td></td><td>Neuroimaging analysis software; http://marsbar.sourceforge.net/</td></tr><tr><td>Statistical Parametric Mapping 12</td><td>Wellcome Centre for Human Neuroimaging</td><td></td><td>Neuroimaging analysis software; https://www.fil.ion.ucl.ac.uk/spm/software/spm12/</td></tr><tr><td>Transcranial direct current stimulation device</td><td>Ybrain</td><td>YDS-301N</td><td></td></tr><tr><td>WFU_PickAtlas</td><td>ANSIR Laboratory, Wake Forest University School of Medicine</td><td>Neuroimaging analysis software; https://www.nitrc.org/projects/wfu_pickatlas/</td><td></td></tr></tbody></table>

transcranial direct current stimulation for online gamers

Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique that applies a weak electric current to the scalp to modulate neuronal membrane potentials. Compared to other brain stimulation methods, tDCS is relatively safe, simple, and inexpensive to administer.
Since excessive online gaming can negatively affect mental health and daily functioning, developing treatment options for gamers is necessary. Although tDCS over the dorsolateral prefrontal cortex (DLPFC) has demonstrated promising results for various addictions, it has not been tested in gamers. This paper describes a protocol and a feasibility study for applying repeated tDCS over the DLPFC and neuroimaging to examine the underlying neural correlates in gamers.
At baseline, individuals who play online games report average weekly hours spent on games, complete questionnaires on addiction symptoms and self-control, and undergo brain 18F-&#64258;uoro-2-deoxyglucose positron emission tomography (FDG-PET). The tDCS protocol consists of 12 sessions over the DLPFC for 4 weeks (anode F3/cathode F4, 2 mA for 30 min per session). Then, a follow-up is conducted using the same protocol as the baseline. Individuals who do not play online games receive only baseline FDG-PET scans without tDCS. Changes of clinical characteristics and asymmetry of regional cerebral metabolic rate of glucose (rCMRglu) in the DLPFC are examined in gamers. In addition, asymmetry of rCMRglu is compared between gamers and non-gamers at baseline.
In our experiment, 15 gamers received tDCS sessions and completed baseline and follow-up scans. Ten non-gamers underwent FDG-PET scans at the baseline. The tDCS reduced addiction symptoms, time spent on games, and increased self-control. Moreover, abnormal asymmetry of rCMRglu in the DLPFC at baseline was alleviated after tDCS.
The current protocol may be useful for assessing treatment efficacy of tDCS and its underlying brain changes in gamers. Further randomized sham-controlled studies are warranted. Moreover, the protocol can be applied to other neurological and psychiatric disorders.

A total of 15 gamers (Table 1) and 10 non-gamers were recruited. The mean age of the gamer group (21.3 &#177; 1.4) was significantly lower than that of the non-gamer group (28.8 &#177; 7.5) (t = -3.81, p &#60; 0.001). There were 8 men in the gamer group and 6 men in the non-gamer group (&#967;2 = 0.11, p = 0.74).
Behavioral results using linear mixed models indicate that the tDCS sessions successfully lowered the IAT score (z = -4.29, p &#60; 0.001), weekly hours sp...

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Transcranial Direct Current Stimulation for Online Gamers

We present a protocol and a feasibility study for applying transcranial direct current stimulation (tDCS) and neuroimaging assessment in online gamers.

Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique that applies a weak electric current to the scalp to modulate ...

transcranial-direct-current-stimulation-for-online-gamers

Research

JoVE Journal

Behavior

8.0K Views.  The Catholic University of Korea. Ons protocol maakt gebruik van een niet-invasieve hersenen modulatie techniek genaamd transcraniële direct current stimulatie, of tDCS, om online gaming gebruik te verminderen. tDCS is eenvoudig, veilig en goedkoop toedienen, in vergelijking met andere hersenstimulatietechnieken. We gebruiken ook neuroimaging om veranderingen in de hersenen in verband met stimulatie te beoordelen.Na het werven van zowel online game spelen en niet-online game spelen individuen, leg aan elke deelnemer h...

Video: Transcranial Direct Current Stimulation for Online Gamers

Simultaneous EEG Monitoring During Transcranial Direct Current Stimulation

Transcranial direct current stimulation (tDCS) is a technique that delivers weak electric currents through the scalp. This constant electric current induces shifts in neuronal membrane excitability, resulting in secondary changes in cortical activity. Although tDCS has most of its neuromodulatory effects on the underlying cortex, tDCS effects can also be observed in distant neural networks. Therefore, concomitant EEG monitoring of the effects of tDCS can provide valuable information on the mechanisms of tDCS. In addition, EEG findings can be an important surrogate marker for the effects of tDCS and thus can be used to optimize its parameters. This combined EEG-tDCS system can also be used for preventive treatment of neurological conditions characterized by abnormal peaks of cortical excitability, such as seizures. Such a system would be the basis of a non-invasive closed-loop device. In this article, we present a novel device that is capable of utilizing tDCS and EEG simultaneously. For that, we describe in a step-by-step fashion the main procedures of the application of this device using schematic figures, tables and video demonstrations. Additionally, we provide a literature review on clinical uses of tDCS and its cortical effects measured by EEG techniques.

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that has shown initial therapeutic effects in several neurological conditions. The main mechanism underlying these therapeutic effects is the modulation of cortical excitability. Therefore, online monitoring of cortical excitability would help guide stimulation parameters and optimize its therapeutic effects. In the present article we review the use of a novel device that combines simultaneous tDCS and EEG monitoring in real time.

Transcranial  direct current stimulation (tDCS) is a technique that delivers weak electric  currents through the scalp. This constant electric current ...

Transcranial Direct Current Stimulation and Simultaneous  Functional Magnetic Resonance Imaging

Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique that uses weak electrical currents administered to the scalp to manipulate cortical excitability and, consequently, behavior and brain function. In the last decade, numerous studies have addressed short-term and long-term effects of tDCS on different measures of behavioral performance during motor and cognitive tasks, both in healthy individuals and in a number of different patient populations. So far, however, little is known about the neural underpinnings of tDCS-action in humans with regard to large-scale brain networks. This issue can be addressed by combining tDCS with functional brain imaging techniques like functional magnetic resonance imaging (fMRI) or electroencephalography (EEG).
In particular, fMRI is the most widely used brain imaging technique to investigate the neural mechanisms underlying cognition and motor functions. Application of tDCS during fMRI allows analysis of the neural mechanisms underlying behavioral tDCS effects with high spatial resolution across the entire brain. Recent studies using this technique identified stimulation induced changes in task-related functional brain activity at the stimulation site&#160;and also in more distant brain regions, which were associated with behavioral improvement. In addition, tDCS administered during resting-state fMRI allowed identification of widespread changes in whole brain functional connectivity.
Future studies using this combined protocol should yield new insights into the mechanisms of tDCS action in health and disease and new options for more targeted application of tDCS in research and clinical settings. The present manuscript describes this novel technique in a step-by-step fashion, with a focus on technical aspects of tDCS administered during fMRI.

Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique. It has successfully been used in basic research and clinical settings to modulate brain function in humans. This article describes the implementation of tDCS and simultaneous functional magnetic resonance imaging (fMRI), to investigate the neural basis of tDCS effects.

Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique that uses weak electrical currents administered to the scalp ...

Technique and Considerations in the Use of 4x1 Ring High-definition Transcranial Direct Current Stimulation (HD-tDCS)

High-definition transcranial direct current stimulation (HD-tDCS) has recently been developed as a noninvasive brain stimulation approach that increases the accuracy of current delivery to the brain by using arrays of smaller "high-definition" electrodes, instead of the larger pad-electrodes of conventional tDCS. Targeting is achieved by energizing electrodes placed in predetermined configurations. One of these is the 4x1-ring configuration. In this approach, a center ring electrode (anode or cathode) overlying the target cortical region is surrounded by four return electrodes, which help circumscribe the area of stimulation. Delivery of 4x1-ring HD-tDCS is capable of inducing significant neurophysiological and clinical effects in both healthy subjects and patients. Furthermore, its tolerability is supported by studies using intensities as high as 2.0 milliamperes for up to twenty minutes.
Even though 4x1 HD-tDCS is simple to perform, correct electrode positioning is important in order to accurately stimulate target cortical regions and exert its neuromodulatory effects. The use of electrodes and hardware that have specifically been tested for HD-tDCS is critical for safety and tolerability. Given that most published studies on 4x1 HD-tDCS have targeted the primary motor cortex (M1), particularly for pain-related outcomes, the purpose of this article is to systematically describe its use for M1 stimulation, as well as the considerations to be taken for safe and effective stimulation. However, the methods outlined here can be adapted for other HD-tDCS configurations and cortical targets.

Technique and Considerations in the Use of 4x1 Ring High-definition Transcranial Direct Current Stimulation HD-tDCS

High-definition transcranial direct current stimulation (HD-tDCS), with its 4x1-ring montage, is a noninvasive brain stimulation technique that combines both the neuromodulatory effects of conventional tDCS with increased focality. This article provides a systematic demonstration of the use of 4x1 HD-tDCS, and the considerations needed for safe and effective stimulation.

High-definition transcranial direct current stimulation (HD-tDCS) has recently been developed as a noninvasive brain stimulation approach that increases ...

Medicine

Effects of Transcranial Alternating Current Stimulation on the Primary Motor Cortex by Online Combined Approach with Transcranial Magnetic Stimulation

Transcranial Alternating Current Stimulation (tACS) is a neuromodulatory technique able to act through sinusoidal electrical waveforms in a specific frequency and in turn modulate ongoing cortical oscillatory activity. This neurotool allows the establishment of a causal link between endogenous oscillatory activity and behavior. Most of the tACS studies have shown online effects of tACS. However, little is known about the underlying action mechanisms of this technique because of the AC-induced artifacts on Electroencephalography (EEG) signals. Here we show a unique approach to investigate online physiological frequency-specific effects of tACS of the primary motor cortex (M1) by using single pulse Transcranial Magnetic Stimulation (TMS) to probe cortical excitability changes. In our setup, the TMS coil is placed over the tACS electrode while Motor Evoked Potentials (MEPs) are collected to test the effects of the ongoing M1-tACS. So far, this approach has mainly been used to study the visual and motor systems. However, the current tACS-TMS setup can pave the way for future investigations of cognitive functions. Therefore, we provide a step-by-step manual and video guidelines for the procedure.

Transcranial Alternating Current Stimulation (tACS) allows the modulation of cortical excitability in a frequency-specific fashion. Here we show a unique approach which combines online tACS with single pulse Transcranial Magnetic Stimulation (TMS) in order to "probe" cortical excitability by means of Motor Evoked Potentials.

Transcranial Alternating Current Stimulation (tACS) is a neuromodulatory technique able to act through sinusoidal electrical waveforms in a specific ...

Neuroscience

Remotely Supervised Transcranial Direct Current Stimulation: An Update on Safety and Tolerability

The remotely supervised tDCS (RS-tDCS) protocol enables participation from home through guided and monitored self-administration of tDCS treatment while maintaining clinical standards. The current consensus regarding the efficacy of tDCS is that multiple treatment sessions are needed to observe targeted behavioral reductions in symptom burden. However, the requirement for patients to travel to clinic daily for stimulation sessions presents a major obstacle for potential participants, due to work or family obligations or limited ability to travel. This study presents a protocol that directly overcomes these obstacles by eliminating the need to travel to clinic for daily sessions.
This is an updated protocol for remotely supervised self-administration of tDCS for daily treatment sessions paired with a program of computer-based cognitive training for use in clinical trials. Participants only need to attend clinic twice, for a baseline and study-end visit. At baseline, participants are trained and provided with a study stimulation device, and a small laptop computer. Participants then complete the remainder of their stimulation sessions at home while they are monitored via videoconferencing software.
Participants complete computerized cognitive remediation during stimulation sessions, which may serve a therapeutic role or as a &#34;placeholder&#34; for other computer-based activity. Computers are enabled for real-time monitoring and remote control by study staff.
Outcome measures that assess feasibility and tolerance are administered remotely with the aid of visual analogue scales that are presented onscreen. Following completion of all RS-tDCS sessions, participants return to clinic for a study end visit in which all study equipment is returned.
Results support the safety, feasibility, and scalability of the RS-tDCS protocol for use in clinical trials. Across 46 patients, 748 RS-tDCS sessions have been completed. This protocol serves as a model for use in future clinical trials involving tDCS.

This manuscript provides an updated remote supervision protocol that enables participation in transcranial direct current stimulation (tDCS) clinical trials while receiving treatment sessions from home. The protocol has been successfully piloted in both patients with multiple sclerosis and Parkinson&#39;s disease.

The remotely supervised tDCS (RS-tDCS) protocol enables participation from home through guided and monitored self-administration of tDCS treatment while ...

Home-Based Transcranial Direct Current Stimulation Device Development: An Updated Protocol Used at Home in Healthy Subjects and Fibromyalgia Patients

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation (NIBS) method, which modulates the membrane potential of neurons in the cerebral cortex by a low-intensity direct current. tDCS is a low-cost technique with minimal adverse effects and easy application. This neurostimulation method has a promising future to improve pain therapy, treatment of neuropsychiatric disorders, and physical rehabilitation.
Current studies demonstrate the benefits of using tDCS over consecutive multiple sessions. However, the daily displacement to the specialized centers, travel costs, and disruptions to daily activities are some of the difficulties faced by patients. Thus, to be more comfortable, easy-to-use, and not disrupt daily commitments, a home-based tDCS was designed. Therefore, the objective of this study was to evaluate the feasibility of a portable tDCS device for home use in healthy subjects and fibromyalgia patients.
Despite increased tDCS use and a reasonably large body of research on the effects across a range of clinical conditions, there is a limited amount of research on developing secure devices that guarantee the dose and contain a block system to avoid excessive use. Therefore, we used a tDCS device with a security system to permit daily use for 20 minutes with a minimal interval of 12 hours between sessions. A programmer preconfigures the equipment, which has a neoprene cap that allows the electrode positions in any assembly, according to individualized protocols for treatments or research. After, researchers can assess the effectiveness of treatment, and its adherence using information kept in the device software.
Results suggest that the device is feasible for home use, with proper monitoring of adherence and contact impedance. There were reports of a few adverse effects, which do not differ from those reported in the literature in studies with the treatment under direct supervision.

This study provides an updated home-based tDCS protocol that enables subjects to receive the beneficial effects of tDCS at home with an easy to use device with settings to control the use and dosage, enhancing the feasibility for long-term use at home.

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation (NIBS) method, which modulates the membrane potential of neurons in the ...

Stimulation Location Determination using a 3D Digitizer with High-Definition Transcranial Direct Current Stimulation

The abundance of neuroimaging data and rapid development of machine learning has made it possible to investigate brain activation patterns. However, causal evidence of brain area activation leading to a behavior is often left missing. Transcranial direct current stimulation (tDCS), which can temporarily alter brain cortical excitability and activity, is a noninvasive neurophysiological tool used to study causal relationships in the human brain. High-definition transcranial direct current stimulation (HD-tDCS) is a noninvasive brain stimulation (NIBS) technique that produces a more focal current compared to conventional tDCS. Traditionally, the stimulation location has been roughly determined through the 10-20 EEG system, because determining precise stimulation points can be difficult. This protocol uses a 3D digitizer with HD-tDCS to increase accuracy in determination of stimulation points. The method is demonstrated using a 3D digitizer for more accurate localization of stimulation points in the right temporo-parietal junction (rTPJ).

Presented here is a protocol to achieve higher accuracy in determination of stimulation location combining a 3D digitizer with high-definition transcranial direct current stimulation.

The abundance of neuroimaging data and rapid development of machine learning has made it possible to investigate brain activation patterns. However, ...

Updated Technique for Reliable, Easy, and Tolerated Transcranial Electrical Stimulation Including Transcranial Direct Current Stimulation

Transcranial direct current stimulation (tDCS) is a noninvasive method of neuromodulation using low-intensity direct electrical currents. This method of brain stimulation presents several potential advantages compared to other techniques, as it is noninvasive, cost-effective, broadly deployable, and well-tolerated provided proper equipment and protocols are administered. Even though tDCS is apparently simple to perform, correct administration of the tDCS session, especially the electrode positioning and preparation, is vital for ensuring reproducibility and tolerability. The electrode positioning and preparation steps are traditionally also the most time consuming and error-prone. To address these challenges, modern tDCS techniques, using fixed-position headgear and pre-assembled sponge electrodes, reduce complexity and setup time while also ensuring that the electrodes are consistently placed as intended. These modern tDCS methods present advantages for research, clinic, and remote-supervised (at home) settings. This article provides a comprehensive step-by-step guide for administering a tDCS session using fixed-position headgear and pre-assembled sponge electrodes. This guide demonstrates tDCS using commonly applied montages intended for motor cortex and dorsolateral prefrontal cortex (DLPFC) stimulation. As described, selection of the head size and montage-specific headgear automates electrode positioning. Fully assembled pre-saturated snap-electrodes are simply affixed to the set position snap-connectors on the headgear. The modern tDCS method is shown to reduce setup time and reduce errors for both novice and expert operators. The methods outlined in this article can be adapted to different applications of tDCS as well as other forms of transcranial electrical stimulation (tES) such as transcranial alternating current stimulation (tACS) and transcranial random noise stimulation (tRNS). However, since tES is application specific, as appropriate, any methods recipe is customized to accommodate subject, indication, environment, and outcome specific features.

When administering transcranial direct current stimulation (tDCS), reproducible electrode preparation and placement are vital for a tolerated and effective session. The purpose of this article is to demonstrate updated modern setup procedures for the administration of tDCS and related transcranial electrical stimulation techniques, such as transcranial alternating current stimulation (tACS).

Transcranial direct current stimulation (tDCS) is a noninvasive method of neuromodulation using low-intensity direct electrical currents. This method of ...

Simultaneous Application of Transcranial Direct Current Stimulation during Virtual Reality Exposure

Transcranial direct current stimulation (tDCS) is a form of non-invasive brain stimulation that changes the likelihood of neuronal firing through modulation of neural resting membranes. Compared to other techniques, tDCS is relatively safe, cost-effective, and can be administered while individuals are engaged in controlled, specific cognitive processes. This latter point is important as tDCS may predominantly affect intrinsically active neural regions. In an effort to test tDCS as a potential treatment for psychiatric illness, the protocol described here outlines a novel procedure that allows the simultaneous application of tDCS during exposure to trauma-related cues using virtual reality (tDCS+VR) for veterans with posttraumatic stress disorder (NCT03372460). In this double-blind protocol, participants are assigned to either receive 2 mA tDCS, or sham stimulation, for 25 minutes while passively watching three 8-minute standardized virtual reality drives through Iraq or Afghanistan, with virtual reality events increasing in intensity during each drive. Participants undergo six sessions of tDCS+VR over the course of 2-3 weeks, and psychophysiology (skin conductance reactivity) is measured throughout each session. This allows testing for within and between session changes in hyperarousal to virtual reality events and adjunctive effects of tDCS. Stimulation is delivered through a built-in rechargeable battery-driven tDCS device using a 1 (anode) x 1 (cathode) unilateral electrode set-up. Each electrode is placed in a 3 x 3 cm (current density 2.22 A/m2) reusable sponge pocket saturated with 0.9% normal saline. Sponges with electrodes are attached to the participant&#8217;s skull using a rubber headband with the electrodes placed such that they target regions within the ventromedial prefrontal cortex. The virtual reality headset is placed over the tDCS montage in such a way as to avoid electrode interference.

This manuscript outlines a novel protocol to allow the simultaneous application of transcranial direct current stimulation during exposure to warzone trauma-related cues using virtual reality for veterans with posttraumatic stress disorder.

Transcranial direct current stimulation (tDCS) is a form of non-invasive brain stimulation that changes the likelihood of neuronal firing through ...

Treatment of Phantom Limb Pain by Remote Transcranial Direct Current Stimulation

Using Home-based, Remotely Supervised, Transcranial Direct Current Stimulation for Phantom Limb Pain

Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique that uses low-amplitude direct currents to alter cortical excitability. Previous trials have established the safety and tolerability of tDCS, and its potential to mitigate symptoms. However, the effects are cumulative, making it more difficult to have adherence to the treatment since frequent visits to the clinic or outpatient center are required. Moreover, the time needed for transportation to the center and the related expenses limit the accessibility of the treatment for many participants.
Following guidelines for remotely supervised transcranial direct current stimulation (RS-tDCS) implementation, we propose a protocol designed for remotely supervised and home-based participation that uses specific devices and materials modified for patient use, with real-time monitoring by researchers through an encrypted video conferencing platform. We have developed detailed instructional materials and structured training procedures to allow for self- or proxy-administration while supervised remotely in real time. This protocol has a specific design to have a series of checkpoints during training and execution of the visit. This protocol is currently in use in a large pragmatic study of RS-tDCS for phantom limb pain (PLP). In this article, we will discuss the operational challenges of conducting a home-based RS-tDCS session and show methods to enhance its efficacy with supervised sessions.

Author Spotlight: Insights into Remotely Supervised Neuromodulation Procedure for Phantom Limb Pain

The goal of this study is to describe a protocol for the home-based delivery of remotely supervised transcranial direct current stimulation (RS-tDCS) conserving the standard procedures of in-clinic practice, including safety, reproducibility, and tolerability. The participants included will be patients with phantom limb pain (PLP).

Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique that uses low-amplitude direct currents to alter cortical ...

Transcranial Direct Current Stimulation for Online Gamers

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