- The priming effect of dual tDCS was important to facilitate motor recovery in combination with mirror therapy in stroke.
Posts Tagged tDCS
[Abstract] Timing-dependent interaction effects of tDCS with mirror therapy on upper extremity motor recovery in patients with chronic stroke: A randomized controlled pilot study
This study was a randomized, controlled pilot trial to investigate the timing-dependent interaction effects of dual transcranial direct current stimulation (tDCS) in mirror therapy (MT) for hemiplegic upper extremity in patients with chronic stroke. Thirty patients with chronic stroke were randomly assigned to three groups: tDCS applied before MT (prior-tDCS group), tDCS applied during MT (concurrent-tDCS group), and sham tDCS applied randomly prior to or concurrent with MT (sham-tDCS group). Dual tDCS at 1 mA was applied bilaterally over the ipsilesional M1 (anodal electrode) and the contralesional M1 (cathodal electrode) for 30 min. The intervention was delivered five days per week for two weeks. Upper extremity motor performance was measured using the Fugl-Meyer Assessment-Upper Extremity (FMA-UE), the Action Research Arm Test (ARAT), and the Box and Block Test (BBT). Assessments were administered at baseline, post-intervention, and two weeks follow-up. The results indicated that concurrent-tDCS group showed significant improvements in the ARAT in relation to the prior-tDCS group and sham-tDCS group at post-intervention. Besides, a trend toward greater improvement was also found in the FMA-UE for the concurrent-tDCS group. However, no statistically significant difference in the FMA-UE and BBT was identified among the three groups at either post-intervention or follow-up. The concurrent-tDCS seems to be more advantageous and time-efficient in the context of clinical trials combining with MT. The timing-dependent interaction factor of tDCS to facilitate motor recovery should be considered in future clinical application.
via Timing-dependent interaction effects of tDCS with mirror therapy on upper extremity motor recovery in patients with chronic stroke: A randomized controlled pilot study – Journal of the Neurological Sciences
Non-invasive Brain Stimulation (NIBS) techniques are used to modulate brain activity in a safe and well-tolerated way . In particular, Transcranial direct current stimulation (tDCS), uses low-intensity electrical currents to modulate cortical excitability in a polarity-specific manner . Classical tDCS montages consist of two rectangular sponge electrodes with a contact area of ∼25-35 cm2, where electrical current between 0.5mA and 4mA flows from a positively charged electrode (anode) to a negative one (cathode) passing through various tissue compartments including skin, muscle, bone, cerebrospinal fluid and brain. Due to its safety and relatively low-cost, tDCS experiments have been widely carried out to investigate human neurophysiology and to test its application as a new potential therapeutic solution for neurological and psychiatric conditions. To ensure adequate understanding of the observed effects, however, researchers need to rely on valid and approved control placebo conditions, a fundamental requirement in randomized controlled trials. Traditional standard sham protocols consist on an initial ramp up of the current, followed by a short stimulation period (usually for 5-60 seconds) and a final ramp down [, , ], (i.e., Fade In of current, brief real Stimulation, Fade-Out; commonly known as “FISSFO” protocol), an approach thought to cause sensory stimulation similar to real tDCS without affecting cortico-spinal excitability . However, both these assumptions (i.e., adequate blinding and absence of effects on the brain) are still under examination. FISSFO sham has been considered effective in providing a proper blinding when compared with real tDCS at 1mA for 20 minutes , becoming the standard for sham tDCS . The rationale stems from participants’ reports in which the cutaneous perceptions that generally cue subjects on tDCS being effectively delivered (i.e., tingling or itching sensation), have been mostly reported during the first 30-60 seconds of stimulation to then gradually decrease, possibly due to habituation . However, a recent investigation has revealed that even naïve subjects (N=192) are capable of distinguishing classic sham stimulation (FISSFO) from active tDCS when delivered at 1 mA for 20 minutes over the left dorsolateral prefrontal cortex (DLPFC) . Prior experiments had already suggested blinding inefficacy when real tDCS is applied at 1.5-2 mA, even for only 10 minutes [9,10]. Accordingly, non-naïve subjects seem more capable of distinguishing real from sham tDCS  and extreme individual variability has been reported with regard to sensibility to stimulation intensity and duration, with subjects being able to perceive tDCS even at very low intensity (i.e., 400 μA) .
On the other hand, additional sham protocols have been developed with modified durations of ramp up/down, or even delivering constant low intensity currents (0.016 or 0.034 mA) [7,12,13]. However, these approaches have not been properly tested on large sample of patients/subjects, with no data on the effects of such alternative sham protocols on the brain, while inconsistent results on many neurophysiological parameters have been documented when adopting such modified approaches .
Beyond the single or double blinding efficacy of FISSFO and related approaches , an element of interest is the question of whether tDCS effects are due to cortical interaction of the generated electric fields or from peripheral nervous system (PNS) stimulation. Since the ramp-up/ramp-down method for blinding decreases both cortical and peripheral stimulation, they cannot help disentangling cortical and peripheral effects. In addition, cortical effects of the brief period of real stimulation during sham protocols may not completely be excluded .
An additional challenge is the fact that the induced tDCS electric field is conditioned by the heterogeneity of cortical and non-cortical tissues, as well as by the complexity of cortical geometry . In recent years, this has been addressed by the use of multichannel tDCS systems in combination with realistic finite element modeling of current propagation in the head derived from subject neuroimaging data (e.g. MRI, fMRI) [17,18]. The rationale for multifocal stimulation resides on both the need for more targeted stimulation of the cortex, as well as the notion that brain regions operate in networks and communicate with each other’s through modulatory interactions [, , ]. Realistic physical models provide a crucial element for better experimental understanding and control of the electric fields generated by tDCS.
In the present study, we investigate a novel approach to sham stimulation based on controlled shunting of currents via a model-based quantification of transcutaneous and transcranial effects. Specifically, the novel sham tDCS solution benefits from the use of an optimization algorithm allowing tDCS montages to be tailored in such a way that zero or very low magnitude electric fields are delivered on the brain, while medium to high intensity currents are maintained in at least some scalp electrodes, thus eliciting scalp sensations necessary for blinding. Notably, this allows to maintain the stimulation ON for the entire duration of sham tDCS, therefore inducing scalp sensations similar to real tDCS, while avoiding known limitations of the FISSFO protocol. We hypothesize that such montage (Active Sham, ActiSham hereafter) (i) will generate scalp sensations similar to a Multifocal (real) tDCS montage based on the same electrodes’ location and identical stimulation intensity/duration; and that (ii) ActiSham will not induce changes in cortico-spinal excitability (CSE), as assessed through Motor Evoked Potentials (MEPs) induced by Transcranial Magnetic Stimulation (TMS) as an index of corticospinal excitability. If successful, this and similar other approaches for improved sham stimulation could contribute to more efficient design of future tDCS research studies and clinical trials.
Fourteen subjects participated in 4 randomized tDCS stimulation visits, spaced 7±3 days to ensure no carryover effects. The tDCS conditions were: real Bifocal-tDCS, Bifocal-Sham, real Multifocal-tDCS and ActiSham. Each session lasted approximately 90 minutes during which participants seated in a comfortable chair with their eyes open. To measure changes in corticospinal excitability, single pulse TMS was applied over the left primary motor cortex (M1) at the beginning and the end of each stimulation session. Somatosensory sensations elicited by tDCS were addressed by means of ad-hoc questionnaires. See dedicated sections below for further details about tools and procedures.
Fourteen healthy right-handed naïve subjects (25.4 years ± 2.1; 5 males) were recruited at the University Campus of Siena, School of Medicine (Siena, Italy). Possible contraindications to either TMS or tDCS were assessed by means of a screening questionnaire . Exclusion criteria included: history of seizures, head injury, pacemakers or other implanted medical devices, metallic objects in the head, hearing impairments, medications altering cortical excitability or other significant medical concerns. All participants gave written informed consent prior to participating to the study. The research proposal and associated methodologies were approved by the local ethical committee in accordance with the principles of the Declaration of Helsinki.
tDCS sessions lasted 15 minutes, with electrode types, scalp montages and stimulation intensities customized for each tDCS protocol (Figure 1). Transcranial stimulation was delivered using a “Starstim 8” brain stimulator controlled via Bluetooth using a laptop computer (Neuroelectrics, Barcelona, Spain). For canonical Bifocal-tDCS (active or sham), stimulation was delivered through traditional 5×7 cm rectangular sponge electrodes, with a contact area of 35 cm2 (SPONSTIM, Neuroelectrics, Barcelona, Spain). Before current delivery, electrodes were soaked with 15 ml of sterile sodium chloride solution (0.9%). For Multichannel stimulation conditions (real and ActiSham), current was instead delivered using circular Ø 20 mm PISTIM electrodes (Neuroelectrics, Barcelona, Spain) with an Ag/AgCl core and a gel/skin contact area of 3.14 cm2. Electrodes were filled with a conductive gel before the tDCS intervention. To further improve current conductivity, the scalp was gently rubbed with an alcohol solution at the beginning of each session. Electrodes were inserted in a neoprene cap with available positions following the 10/20 EEG system.
At Neuroelectrics, we believe in the advantages and effectiveness of transcranial electric stimulation (tES) in treating numerous brain diseases. Yet, despite the increasing number of tES publications per year, the lion’s share in the market of non-invasive brain stimulation technologies is still played by transcranial magnetic stimulation (TMS), likely because TMS received US-FDA approval in 2008 whereas tES has not yet.
Does this mean TMS is more effective? Well, it’s not quite fair to say so, considering TMS studies started at least 10 years earlier than those of tES. Therefore, there are several more clinical trials proving TMS efficacy.
However, the two techniques are close relatives: you can think of TMS as the elderly, stiff and sturdy brother, and tES as the younger, more flexible and easy-going one.
In this blogpost, we’ll go over the roots of their differences and see when and why you might prefer one over the other.
[E-fields patterns and biophysical substrates]
At a fundamental level, the two techniques rely on different physics and induce distinct patterns of electric fields (E-field) on the cortex, acting on a different neural substrate.
TMS is based on electromagnetic induction: a large magnetic coil is placed just a few centimetres above the scalp to stimulate over a specific cortical area. When the operator launches the electric pulse, vast amounts of current flows suddenly through the coil and creates a magnetic field around it, which varies rapidly in time. This changing magnetic field induces a very short (order of 1ms), highly localized (figure 1), super-threshold (order of 100V/m) E-field in the cortex. The E-field maximum is reached on the gyrus right under the coil, and the orientation is mostly parallel to the cortical surface.
The most sensitive cells to an E-field with such characteristics are interneurons and collaterals of pyramidal cells aligned tangentially to the cortical surface, which are automatically triggered to fire.
Instead, tES operates in the (quasi-)static regime, as only a small amount of direct current (DC) or low frequency alternating current (AC) is applied through electrodes placed directly on the scalp. The temporal resolution of the technique is low because the neuromodulatory effects begins a few seconds after the start of stimulation. Moreover, the E-field generated is much weaker (order of 0.1V/m) and less focalized (although the focality can be improved by using multichannel montages, it remains much lower than TMS E-field). Depending on the electrodes’ geometry, the maxima can occur on the gyri at the edges of the electrodes or between them. The overall orientation of the E-field is normal to the cortical surface, which indicates that tES probably influences layer V pyramidal neurons, as they are mostly perpendicular to the cortex.
Given the low, subthreshold intensity, the tES E-field cannot cause neural firing, but it is able to modulate the firing rate, facilitating or inhibiting the activation of pyramidal cells.
Other important differences concerning system setup.
TMS technology is more complex and cumbersome. The cost of the whole equipment is between 50-100k USD or Euros. This includes a wall-powered and heavy stimulator about the size of a fridge, a coil connected to the stimulator by a high-voltage cable, a mechanical arm to hold it in place, and a neuro-navigation system to accurately place the coil over the target brain region. The coil hangs suspended over the head of the patient, and since the strength of the effects depends on the coil-cortex distance, it’s crucial to keep it at the specific distance. For this, during the treatment session, the patient must sit still in a specially designed chair, with positioning frames around the chin and forehead.
On the contrary, tES is much cheaper and effortless: the cost is between an average of 6-30k USD/Euros, and the whole setup fits a shoe box. The stimulator can be as small as a mobile phone, light/portable, and almost always battery powered. The electrodes are directly in contact with the scalp, held in place by a rubber band or a neoprene cap. This way, the patient can move and even walk during the stimulation session.
Despite the underlying differences, TMS and tES are both quite versatile tools for treatment and research, and they offer similar options.
In research settings, you can leverage on TMS’ high spatial and temporal resolution to study how brain networks dynamically operate. In this context, TMS is usually performed online (during task performance) by applying one pulse at the onset of a stimulus (single-pulse TMS), or two pulses over separate regions which are interconnected (paired-pulses TMS). But tES too allows one to study the causal link between cortical areas. For instance, with tACS, one can simultaneously apply oscillatory currents over distinct regions at the same frequency but with different phases to promote or hamper the synchronization of functional networks.
Clinical applications of brain stimulation techniques instead tend to focus more on long-term effects, promoting network neuroplasticity that can outlast the period of stimulation.
In this case, TMS is usually ran in the repetitive mode (rTMS), which consists in multiple pulses within just microseconds. Frequency lower than 1Hz has been linked to long term depression (LTD), whereas frequency above 5Hz to long term potentiation (LTP). Similar outcomes can be achieved with tCS using either tDCS anodal or cathodal stimulation, which has been shown promoting and inhibiting synaptic activation, respectively.
The side effects of both techniques are quite moderate – with one important exception. While tES can induce only mild and temporary itching, tingling, and skin reddening when done properly, TMS might cause mild headaches, facial twitching, seizures in extreme cases.
For both TMS and tES, medical treatment must be performed mostly in clinical settings, which means you will have to find a clinician who provides these services in their clinic. However, one of the strengths of tES is the possibility to perform stimulation telemedically (under the remote guidance of a clinicians) via home-treatment. This is important as it will boost therapeutic effects for pathologies such as motor rehabilitation, depression, Alzheimer’s disease, etc in the comfort of one’s home. And it has been shown that the number of sessions modulates the length of the long-term plastic effects.
Interested in home-application of tCS? Check our home-kit here.
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Salvador R., Wenger C., Miranda P.C. Investigating the cortical regions involved in MEP modulation in tDCS, Front. Cell. Neurosci. 9:405 (2015)
[Abstract] Effects of Bihemispheric Transcranial Direct Current Stimulation on Upper Extremity Function in Stroke Patients: A randomized Double-Blind Sham-Controlled Study
Neuromodulation expands beyond health care.
On October 4, 2019, a study published in the American Journal of Psychiatry, led by Professor Helen S. Mayberg, M.D. at the Icahn School of Medicine at Mount Sinai and Dr. Andrea Crowell at Emory University, showed that deep brain stimulation for treatment-resistant depression for a majority of the participants had a “robust and sustained antidepressant response” in an over eight-year period, and there were not any suicides.
Earlier this year, in April, Boston University scientists Robert M. G. Reinhart and John A. Nguyen published in Nature Neuroscience a neuromodulation study that demonstrated noninvasive electrical brain stimulation temporarily improved the working memory accuracy in older adults. The study used 84 people—half between the ages of 20-29, and the other half between 60-76 years old.
The scientists hypothesize that their technique improved behavior due to neuroplastic changes in functional connectivity for up to 50 minutes afterward. Additional studies with more test subjects are needed to test the hypothesis and determine the full course potential of the effects.
These are just a few examples of the numerous research studies in neuromodulation. Neuromodulation methods include optogenetics, cochlear implants, retinal implants, deep brain and spinal cord stimulators, pharmacotherapy, and electroceuticals. Potential applications for neuromodulation may include chronic pain management, Alzheimer’s disease, depression, complications due to stroke, traumatic brain injuries, Parkinson’s disease, epilepsy, migraines, spinal cord injuries, and other conditions. Currently, there are over 590 neuromodulation clinical studies worldwide, according to the U.S. National Institute of Health’s Library of Medicine database of privately and publicly funded clinical studies conducted around the world.
Within the growing neuromodulation market, one segment, transcranial direct current stimulation (tDCS), is moving beyond health care and is making inroads into the consumer segment. Transcranial direct current stimulation is a form of noninvasive brain stimulation using a constant weak electrical current. Typically the voltage is less than two milliamps.
One of the earliest records of transcranial direct current stimulation dates to the ancient Roman Empire. The physician to Roman Emperor Tiberius Claudius Nero Caesar, Scribonius Largus, put a live torpedo fish, an electric ray capable of delivering up to 220 volts, directly on a patient in an effort to use the animal’s electrical discharges for pain therapy.
Fast forward to present day, and transcranial direct current stimulation is being used for a variety of purposes as an emerging technology for neuroscientists, elite athletes, e-sports gamers, neurologists, musicians, and psychiatrists—sans the torpedo fish. Instead, electronic devices in various form-factors are used to deliver currents to the human brain noninvasively via the scalp. Consumer-based transcranial direct current stimulation devices operate on the principle of neuroplasticity—the brain’s ability to change neural connections and behavior.
“Neuroplasticity is the property of the brain that enables it to change its own structure and functioning in response to activity and mental experience,” wrote the New York Times bestselling author, psychiatrist, and psychoanalyst, Norman Doidge, FRCPC, in his 2015 book The Brain’s Way of Healing: Remarkable Discoveries and Recoveries from the Frontiers of Neuroplasticity.
An example of a consumer-based transcranial direct current stimulation device is the Halo Sport 2, a wireless headset introduced in January 2019 that stimulates the brain’s motor cortex through electrical currents to create a temporary state of neuroplasticity. Whether the activity is learning music, dance, or sports, the human brain learns movement via the motor cortex.
The device is made by venture-backed startup Halo Neuroscience, a company founded in 2013 by Daniel Chao, Brett Wingeier, Lee von Kraus, Ph.D., and Amol Sarva, with investments from Jazz Venture Partners, Lux Capital, TPG, Andreessen Horowitz, and others. To use the Halo Sport 2 is simple—neuroprime with the headset on for 20 minutes, then train for an hour afterward.
Halo Sport users include athletes, musicians, and the military—such as members of Major League Baseball’s San Francisco Giants, National Basketball Association’s Golden State Warriors, the U.S. Navy SEALs, USA Cycling, the United States Ski Team, Berklee College of Music, Invictus, as well as many others.
World champion triathlete Timothy O’Donnell is a Halo Sport user. O’Donnell has over 50 podium finishes, including 22 wins. He won two IRONMAN titles, six Armed Forces National Championships, nine Ironman 70.3 races, an ITU Long Distance World Champion race, and many other prestigious competitive triathlon medals. As a world-class elite athlete, O’Donnell is constantly seeking innovative ways to improve his performance. He reportedly reached out to Halo Neuroscience after reading about the technology and incorporates Halo Sport neuropriming in his training to give him an edge.
A number of investments in neuroscience companies have emerged in recent years, such as Bryan Johnson’s Kernel, Elon Musk’s Neuralink, and Tej Tadi’s MindMaze. Other neurotechnology startups include Synchron, founded by Nicholas Opie and Thomas Oxley, BIOS founded by Emil Hewage and Oliver Armitage, BrainCo founded by Bicheng Han, Nextmind founded by Gwendal Kerdavid and Sid Kouider, Thync founded by Isy Goldwasser and Jamie Tyler, EMOTIV founded by Tan Le and Dr. Geoff Mackellar, Paradromics founded by Matt Angle, Bitbrain founded by Javier Minguez Zafra and Maria Lopez Valdes, Flow Neuroscience founded by Daniel Månsson and Erik Rehn, Dreem founded by Hugo Mercier and Quentin Soulet de Brugière, Neuros Medical founded by Jon J. Snyder, Neurable founded by James Hamet, Michael Thompson and Ramses Alcaide, Cognixion founded by Andeas Forsland, Q30 Innovations founded by Bruce Angus and Thomas Hoey, Neuroscouting founded by Dr. Wesley Clapp and Dr. Brian Miller, and Meltin MMI founded by Masahiro Kasuya, and Neuropace founded by David R. Fischell.
The global neuromodulation device industry is expected to increase to 13.3 billion by 2022, according to Neurotech Reports figures published in September 2018. Within this growing space, consumer-based transcranial direct current stimulation is an emerging market to watch.
[ARTICLE] Combining transcranial direct-current stimulation with gait training in patients with neurological disorders: a systematic review – Full Text
Transcranial direct-current stimulation (tDCS) is an easy-to-apply, cheap, and safe technique capable of affecting cortical brain activity. However, its effectiveness has not been proven for many clinical applications.
The aim of this systematic review was to determine whether the effect of different strategies for gait training in patients with neurological disorders can be enhanced by the combined application of tDCS compared to sham stimulation. Additionally, we attempted to record and analyze tDCS parameters to optimize its efficacy.
A search in Pubmed, PEDro, and Cochrane databases was performed to find randomized clinical trials that combined tDCS with gait training. A chronological filter from 2010 to 2018 was applied and only studies with variables that quantified the gait function were included.
A total of 274 studies were found, of which 25 met the inclusion criteria. Of them, 17 were rejected based on exclusion criteria. Finally, 8 trials were evaluated that included 91 subjects with stroke, 57 suffering from Parkinson’s disease, and 39 with spinal cord injury. Four of the eight assessed studies did not report improved outcomes for any of its variables compared to the placebo treatment.
There are no conclusive results that confirm that tDCS can enhance the effect of the different strategies for gait training. Further research for specific pathologies, with larger sample sizes and adequate follow-up periods, are required to optimize the existing protocols for applying tDCS.
Difficulty to walk is a key feature of neurological disorders , so much so that recovering and/or maintaining the patient’s walking ability has become one of the main aims of all neurorehabilitation programs . Additionally, the loss of this ability is one of the most significant factors negatively impacting on the social and professional reintegration of neurological patients .
Strategies for gait rehabilitation traditionally focus on improving the residual ability to walk and compensation strategies. Over the last years, a new therapeutic paradigm has been established based on promoting neuroplasticity and motor learning, which has led to the development of different therapies employing treadmills and partial body-weight support, as well as robotic-assisted gait training . Nevertheless, these new paradigms have not demonstrated superior results when compared to traditional therapies [5,6,7], and therefore recent studies advise combining therapies to enhance their therapeutic effect via greater activation of neuroplastic mechanisms .
Transcranial direct-current stimulation (tDCS) is an intervention for brain neuromodulation consisting of applying constant weak electric currents on the patient’s scalp in order to stimulate specific brain areas. The application of the anode (positive electrode) to the primary motor cortex causes an increase in neuron excitability whereas stimulation with the cathode (negative electrode) causes it to decrease .
The effectiveness of tDCS has been proven for treating certain pathologies such as depression, addictions, fibromyalgia, or chronic pain . Also, tDCS has shown to improve precision and motor learning  in healthy volunteers. Improvements in the functionality of upper limbs and fine motor skills of the hand with paresis have been observed in patients with stroke using tDCS, although the results were somewhat controversial [12, 13]. Similarly, a Cochrane review on the effectiveness of tDCS in treating Parkinson’s disease highlights the great potential of the technique to improve motor skills, but the significance level of the evidence was not enough to clearly recommend it . In terms of gait rehabilitation, current studies are scarce and controversial .
Furthermore, tDCS is useful not only as a therapy by itself but also in combination with other rehabilitation strategies to increase their therapeutic potential; in these cases, the subjects’ basal activity and the need for combining the stimulation with the behavior to be enhanced have been highlighted. Several studies have combined tDCS with different modalities of therapeutic exercising, such as aerobic exercise to increase the hypoalgesic effect in patients with fibromyalgia  or muscle strengthening to increase functionality in patients suffering from knee osteoarthritis . Along these lines, various studies have combined tDCS with gait training in patients with neurological disorders, obtaining rather disparate outcomes [17,18,19,20]. As a result, the main aim of this systematic review was to determine whether the application of tDCS can enhance the effectiveness of other treatment strategies for gait training. Additionally, as a secondary objective, we attempted to record and identify the optimal parameters of the applied current since they are key factors for its effectiveness. […]
Continue —> Combining transcranial direct-current stimulation with gait training in patients with neurological disorders: a systematic review | Journal of NeuroEngineering and Rehabilitation | Full Text
The purpose of the present study was to investigate the effects of transcranial direct current stimulation (tDCS) on motor recovery in adult patients with stroke, taking into account the parameters that could influence the motor recovery responses. The second aim was to identify the best tDCS parameters and recommendations available based on the enhanced motor recovery demonstrated by the analyzed studies. Our systematic review was performed by searching full-text articles published before February 18, 2019 in the PubMed database. Different methods of applying tDCS in association with several complementary therapies were identified. Studies investigating the motor recovery effects of tDCS in adult patients with stroke were considered. Studies investigating different neurologic conditions and psychiatric disorders or those not meeting our methodologic criteria were excluded. The main parameters and outcomes of tDCS treatments are reported. There is not a robust concordance among the study outcomes with regard to the enhancement of motor recovery associated with the clinical application of tDCS. This is mainly due to the heterogeneity of clinical data, tDCS approaches, combined interventions, and outcome measurements. tDCS could be an effective approach to promote adaptive plasticity in the stroke population with significant positive premotor and postmotor rehabilitation effects. Future studies with larger sample sizes and high-quality studies with a better standardization of stimulation protocols are needed to improve the study quality, further corroborate our results, and identify the optimal tDCS protocols.
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OSSINING, N.Y., Aug. 16, 2019 /PRNewswire/ — RPW Technology, LLC introduces Liftid Neurostimulation (www.GetLiftid.com), a transcranial direct current stimulation (tDCS) recreational device for consumers that can improve attention, productivity, and memory through mild electrical stimulation. Liftid uses a constant, low-level electric current, passed through two electrodes placed on the forehead area, to stimulate the brain. tDCS is one of the hottest categories in neuroscience today and supported by over 4,000 published studies.
Dr. Ted Schwartz, MD, a New York based neurosurgeon and RPW’s lead scientist, explains, “As has been shown in several studies, tDCS delivers a small amount of electrical current to the cerebral cortex, rendering neurons in the brain more likely to fire. As a result, the user demonstrates increased abilities, alertness and focus.”
In today’s world, most working professionals, college and grad students, video gamers, musicians, and athletes are chemically stimulating their brains through caffeine, sugar, snacks, and performance enhancers. Liftid Neurostimulation uses a safe and effective technology as an alternative to these forms of chemical stimulation.
RPW Technology is proud to be on the forefront of this emerging technology by bringing to market a tDCS device for healthy individuals (ages 18 & up) that is stylish, extremely lightweight (70 grams) including a soft, comfortable, adjustable headband, and easy to operate. Designed and developed by a team of world renowned neuroscientists, Liftid is preset for a 20 minute stimulation session and has many unique features built-in to the device. Using Liftid Neurostimulation for 20 minutes a day trains the brain to maximize attention, focus, alertness, and memory, thus putting the Liftid user in the right mindset to accomplish tasks and elevate performance.
For more information, purchase, and/or instructional video, please visit the Liftid Neurostimulation website at: www.GetLiftid.com. Unit price is $149.00, which includes an attractive and functional storage case with custom accessories and free shipping within the United States. Liftid is packaged for retail sales.
RPW Technology is a New York startup dedicated to the development and marketing of transcranial electrical stimulation devices. The company, in association with Dr. Schwartz and several neuroscientists, set out to develop a high quality, hi-tech, recreational tDCS device to introduce to consumers worldwide.
Contact for RPW Technology, LLC:
Orca Communications Unlimited, LLC
View original content to download multimedia:http://www.prnewswire.com/news-releases/rpw-technology-announces-the-launch-of-liftid-neurostimulation-300902988.html
SOURCE RPW Technology, LLC
[Abstract] Comparison between Transcranial Direct Current Stimulation and Acupuncture on Upper Extremity Rehabilitation in Stroke: A Single-Blind Randomized Controlled Trial
Objective: To compare the effects of transcranial direct current stimulation (TDCS) with traditional Chinese acupuncture on upper-extremity (UE) function among patients with stroke.
Materials and Methods: Participants with subacute to chronic stroke who had moderate to severe UE functional impairment were randomly allocated to the TDCS or electro-acupuncture group, then underwent three weeks of physical therapy and occupational therapy, with 20 minutes of a-TDCS (2 mA) or electro-acupuncture applied during training once weekly. Primary outcome was determined using the Fugl-Meyer Assessment of motor recovery at 1-month follow-up.
Results: The 18 participants were allocated into two groups. Fugl-Meyer Assessment increased in both the TDCS and electroacupuncture groups (5.00±3.08, p=0.001 and 7.4±4.9, p=0.002, respectively). However, no difference was found between groups, and no significant difference was observed in grip strength and task specific performance in both groups.
Conclusion: The application of TDCS might provide benefits in recovering hand motor function among patients with subacute to chronic stroke but does not go beyond those of electro-acupuncture.
via Comparison between Transcranial Direct Current Stimulation and Acupuncture on Upper Extremity Rehabilitation in Stroke: A Single-Blind Randomized Controlled Trial | Hathaiareerug | JOURNAL OF THE MEDICAL ASSOCIATION OF THAILAND
[WEB PAGE] The Use of Noninvasive Brain Stimulation, Specifically Transcranial Direct Current Stimulation After Stroke
Motor impairment is a leading cause of disability after stroke. Approaches such as noninvasive brain stimulation are being investigated to attempt to increase effectiveness of stroke rehabilitation interventions. There are several types of noninvasive brain stimulation: repetitive transcranial magnetic stimulation, transcranial direct stimulation (tDCS), transcranial alternative current stimulation, and transcranial pulsed ultrasound to name a few. Of the types of noninvasive brain stimulation, repetitive transcranial magnetic stimulation and tDCS have been most extensively tested to modulate brain activity and potentially behavior. These two techniques have distinctive modes of action. Repetitive transcranial magnetic stimulation directly stimulates neurons in the brain and, given the appropriate conditions, leads to new action potentials. On the other hand, tDCS polarizes neuronal tissue including neurons and glia modulating ongoing firing patterns. There are also differences in cost, utility, and knowledge skill required to apply tDCS and repetitive transcranial magnetic stimulation. Transcranial direct stimulation is relatively inexpensive, easy to administer, portable, and may be applied while undergoing therapy, with lasting excitability changes detectable up to 90 minutes after administration. Repetitive transcranial magnetic stimulation equipment is bulkier, expensive, technically more challenging, and a patient’s head must remain still when treatment is being applied therefore needs to be administered before or after a session of rehabilitation. Because of these differences, tDCS has been more accessible and has rapidly grew as a potential tool to be used in neurorehabilitation to facilitate retraining of activities of daily living (ADL) capacity and possibly to improve restoration of neurological function after stroke.
There are three current stimulation approaches using tDCS to modulate corticomotor regions after stroke. In anodal stimulation mode, the anode electrode is placed over the lesioned brain area and a reference electrode is applied over the contralateral orbitofrontal cortex. Anodal tDCS is placed over the ipsilesional hemisphere to improve the responses of perilesional areas to training protocols. In cathodal stimulation, the cathode electrode is placed over the nonlesioned brain area and reference electrode over the contralateral (ipsilesional) orbitofrontal cortex. This approach has been predicated on the hypothesis that the nonstroke hemisphere will be inhibited by tDCS resulting in an increased activation of the ipsilesional hemisphere due to rebalancing of a presumably abnormal interhemispheric interaction. Although some studies have shown this approach to be beneficial, the causative role of interhemispheric interaction imbalance has been recently challenged and refuted.1 Thus, if cathodal stimulation approaches are beneficial, the behavioral effect cannot be explained by a presumed correction of abnormal interhemispheric connectivity. Finally, dual tDCS approach involves simultaneous application of the anode over the ipsilesional and the cathode over the contralesional side. Here again, the intended mechanism of action is to rebalance the presumably abnormal interhemispheric interaction.
CLINICAL QUESTIONS ADDRESSED
What is the best tDCS type and electrical configuration? What are the effects of tDCS with rehabilitation program for upper limb recovery after stroke?
RESEARCH FINDINGS OF tDCS
This short article discusses data obtained from a network meta-analysis of randomized controlled trials and a recent meta-analysis. The network meta-analysis included 12 randomized controlled trials including 284 participants examining the effect of tDCS on ADL function in the acute, subacute, and chronic phases after stroke.2 The meta-analysis included 9 studies with 371 participants in any stage after stroke.3
The network meta-analysis found evidence of a significant moderate effect in favor of cathodal tDCS without significant effects of dual tDCS, anodal tDCS, or sham tDCS. There was no difference in safety (as assessed by dropouts and adverse events) between sham tDCS, physical rehabilitation, cathodal tDCS, dual tDCS, and anodal tDCS. Elsner in a previous review of tDCS in 2016 found an effect on improving ADL, as well as function of the arm and lower limb, muscle strength, and cognition. Thus, the findings from the most recent meta-analysis indicating cathodal that tDCS improves ADL capacity are in line with previous meta-analyses. Of note, there was no evidence of an effect of either cathodal or other tDCS stimulation approaches on upper paretic limb impairment after stroke as measured by the Fugl-Meyer scale.
A meta-analysis that included participants in any stage after the stroke showed that tDCS in conjunction with multiple sessions of rehabilitation had no significant effect over delivering therapy alone for upper limb impairment and activity after stroke. This negative finding might be due to patient’s being in an acute, subacute, or chronic stage after stroke as well as variations in the type of therapy performed paired with tDCS (ie, conventional vs. constraint-induced movement therapy vs. robot protocol).
RECOMMENDATIONS FOR PHYSIATRIC PRACTICE
There seems to be a modest effect supporting the use of tDCS as a co-adjuvant of rehabilitation interventions to improve ADLs after stroke. Cathodal tDCS seems to be the most promising approach, especially when applied early after the stroke. However, the evidence remains preliminary and does not warrant a widespread change in clinical rehabilitation practice at this time.
There is no evidence supporting the use of tDCS to improve motor impairment (as measured by the FMS) at this point.
Importantly, tDCS remains as a very safe intervention, with no differences in safety when real vs. control tDCS is applied.