A Feasibility Study of Bilateral Anodal Stimulation of the Prefrontal Cortex Using High-Definition Electrodes in Healthy Participants

J. Xu, S.M. Healy, D.Q. Truong, A. Datta, M. Bikson, M.N. Potenza.

Abstract: Transcranial direct current stimulation (tDCS†) studies often use one anode to increase cortical excitability in one hemisphere. However, mental processes may involve cortical regions in both hemispheres. This study’s aim was to assess the safety and possible effects on affect and working memory of tDCS using two anodes for bifrontal stimulation. A group of healthy subjects participated in two bifrontal tDCS sessions on two different days, one for real and the other for sham stimulation. They performed a working memory task and reported their affect immediately before and after each tDCS session. Relative to sham, real bifrontal stimulation did not induce significant adverse effects, reduced decrement in vigor-activity during the study session, and did not improve working memory. These preliminary findings suggest that bifrontal anodal stimulation is feasible and safe and may reduce task-related fatigue in healthy participants. Its effects on neuropsychiatric patients deserve further study.

Full PDF: Xu_HDtDCS_2015.compressed

Description:
An intensive one-day event with national and international leaders in transcranial direct current stimulation (tDCS) clinical research. The “Updates in tDCS Clinical Trials” mini-symposium will cover recent updates and results in tDCS clinical trials spanning applications in neurology, psychiatry, and rehabilitation. This course is intended for clinicians, researchers, and students employing tDCS. Lecturers will cover emerging techniques, novel developments, and anticipated outcomes for various tDCS applications. Ample time will be allowed for discussion with speakers. Note that tDCS remain an investigational techniques and is not FDA approved for any indication. The “Updates in tDCS Clinical Trials” mini-symposium is scheduled for the day after the NYC tDCS Fellowship. Though the course focuses on practical aspects of tDCS, no hands-on training is provided. This is a lecture series only. These events are separately managed and require separate registration.

Register Now:

• Regular Admissions: $150

• Student Admissions: $100.

Sarantos C, Bekritsky J, Khadka N, Bikson M, Adusumilli P
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Download: PDF published in Journal of Medical Devices DOI

Abstract

We developed and validated a first-generation compact handheld device for real-time wireless monitoring of tissue oxygen saturation during surgical procedures termed wireless intra-operative pulse oximetry (WiPOX). Based on clinical experience gained in our trials [1,9], we present here the design of a second generation WiPOX that includes a reticulated pressure-sensitive head serving two related functions. First, the often-restricted and sensitive environment in which the device is employed constrains both the angle of approach and visibility, necessitating a self-correcting reticulated swiveling head that acts to improve the contact angle between the sensor head and the tissue. Second, because the devices are hand-held, the pressure on the tissue (often a membrane) is determined by the operator; too little pressure produces poor signal to noise ratio (SNR) while too much pressure can occlude blood flow, also reducing SNR and possibly yielding erroneously low oxygenation measurements. To address this, our sensor head includes a novel mounting for multiple “balloon” style pressure sensors that provide feedback on tissue contact pressure and contact angle. The reticulated head and pressure sensor features function in tandem to improve tissue contact and ensure reliable measurements.
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The Escitalopram versus Electric Current Therapy for Treating Depression Clinical Study (ELECT-TDCS): rationale and study design of a non-inferiority, triple-arm, placebo-controlled clinical trial

Full Design Paper Download: ELECT_TDCSdesign_SMI_2015 2

CONTEXT AND OBJECTIVE: Major depressive disorder (MDD) is a common psychiatric condition, mostly treated with antidepressant drugs, which are limited due to refractoriness and adverse effects. We describe the study rationale and design of ELECT-TDCS (Escitalopram versus Electric Current Therapy for Treating Depression Clinical Study), which is investigating a non-pharmacological treatment known as transcranial direct current stimulation (tDCS).

DESIGN AND SETTING: Phase-III, randomized, non-inferiority, triple-arm, placebo-controlled study, ongoing in São Paulo, Brazil.

METHODS: ELECT-TDCS compares the efficacy of active tDCS/placebo pill, sham tDCS/escitalopram 20 mg/day and sham tDCS/placebo pill, for ten weeks, randomizing 240 patients in a 3:3:2 ratio, respectively. Our primary aim is to show that tDCS is not inferior to escitalopram with a non-inferiority margin of at least 50% of the escitalopram effect, in relation to placebo. As secondary aims, we investigate several biomarkers such as genetic polymorphisms, neurotrophin serum markers, motor cortical excitability, heart rate variability and neuroimaging.

RESULTS: Proving that tDCS is similarly effective to antidepressants would have a tremendous impact on clinical psychiatry, since tDCS is virtually devoid of adverse effects. Its ease of use, portability and low price are further compelling characteristics for its use in primary and secondary healthcare. Multimodal investigation of biomarkers will also contribute towards understanding the antidepressant mechanisms of action of tDCS.

CONCLUSION: Our results have the potential to introduce a novel technique to the therapeutic arsenal of treatments for depression.

CLINICAL TRIAL REGISTRATION: ClinicalTrials.Gov NCT01894815

DEVICE: SOTERIX MEDICAL CT 

HEADGEAR: SOTERIX MEDICAL “OLE” EASYSTRAP

Front. Neuroanat., 15 July 2015  Free Online or Download PDF: HD_tDCS_migraine

State-of-art neuroanatomical target analysis of high-definition and conventional tDCS montages used for migraine and pain control

Summary: Although transcranial direct current stimulation (tDCS) studies promise to modulate cortical regions associated with pain, the electric current produced usually spreads beyond the area of the electrodes’ placement. Using a forward-model analysis, this study compared the neuroanatomic location and strength of the predicted electric current peaks, at cortical and subcortical levels, induced by conventional and High-Definition-tDCS (HD-tDCS) montages developed for migraine and other chronic pain disorders. The electrodes were positioned in accordance with the 10–20 or 10–10 electroencephalogram (EEG) landmarks: motor cortex-supraorbital (M1-SO, anode and cathode over C3 and Fp2, respectively), dorsolateral prefrontal cortex (PFC) bilateral (DLPFC, anode over F3, cathode over F4), vertex-occipital cortex (anode over Cz and cathode over Oz), HD-tDCS 4 × 1 (one anode on C3, and four cathodes over Cz, F3, T7, and P3) and HD-tDCS 2 × 2 (two anodes over C3/C5 and two cathodes over FC3/FC5). M1-SO produced a large current flow in the PFC. Peaks of current flow also occurred in deeper brain structures, such as the cingulate cortex, insula, thalamus and brainstem. The same structures received significant amount of current with Cz-Oz and DLPFC tDCS. However, there were differences in the current flow to outer cortical regions. The visual cortex, cingulate and thalamus received the majority of the current flow with the Cz-Oz, while the anterior parts of the superior and middle frontal gyri displayed an intense amount of current with DLPFC montage. HD-tDCS montages enhanced the focality, producing peaks of current in subcortical areas at negligible levels. This study provides novel information regarding the neuroanatomical distribution and strength of the electric current using several tDCS montages applied for migraine and pain control. Such information may help clinicians and researchers in deciding the most appropriate tDCS montage to treat each pain disorder.

Intensity, Duration, and Location of High-Definition Transcranial Direct Current Stimulation for Tinnitus Relief

Neurorehabilitation and Neural Repair DOI: 10.1177/1545968315595286  Download Paper: tDCS_HdtCS_Neurorehabil Neural Repair-2015-Shekhawat-1545968315595286

Giriraj Singh Shekhawat, Frederick Sundram, Marom Bikson, Dennis Truong, Dirk De Ridder, Cathy M. Stinear, David Welch,  Grant D. Searchfield

Background and Objective. Tinnitus is the perception of a phantom sound. The aim of this study was to compare current intensity (center anode 1 mA and 2 mA), duration (10 minutes and 20 minutes), and location (left temporoparietal area [LTA] and dorsolateral prefrontal cortex [DLPFC]) using 4 × 1 high-definition transcranial direct current stimulation (HD- tDCS) for tinnitus reduction. Methods. Twenty-seven participants with chronic tinnitus (>2 years) and mean age of 53.5 years underwent 2 sessions of HD-tDCS of the LTA and DLPFC in a randomized order with a 1 week gap between site of stimulation. During each session, a combination of 4 different settings were used in increasing dose (1 mA, 10 minutes; 1 mA, 20 minutes; 2 mA, 10 minutes; and 2 mA, 20 minutes). The impact of different settings on tinnitus loudness and annoyance was documented. Results. Twenty-one participants (77.78%) reported a minimum of 1 point reduction on tinnitus loudness or annoyance scales. There were significant changes in loudness and annoyance for duration of stimulation, F(1, 26) = 10.08, P < .005, and current intensity, F(1, 26) = 14.24, P = .001. There was no interaction between the location, intensity, and duration of stimulation. Higher intensity (2 mA) and longer duration (20 minutes) of stimulation were more effective. Conclusions. A current intensity of 2 mA for 20-minute duration was the most effective setting used for tinnitus relief. The stimulation of the LTA and DLPFC were equally effective for suppressing tinnitus loudness and annoyance.

Transcranial Direct Current Stimulation (tDCS): What Pain Practitioners Need to Know

By Helena Knotkova, PhD, Adam J. Woods, PhD, Marom Bikson, PhD and Michael A. Nitsche, MD

Non-invasive brain stimulation with tDCS is an emerging tool for adjunctive treatment of pain syndromes. Its long-lasting analgesic effects are probably caused by alterations of activity in cerebral pain-processing networks.

Link

Transcranial direct current stimulation in obsessive–compulsive disorder: emerging clinical evidence and considerations for optimal montage of electrodes

Expert Rev. Med. Devices, 1–11 (2015)

Full PDF: tDCSforOCD

Natasha M Senco, Yu Huang, Giordano D’Urso, Lucas C Parra, Marom Bikson, Antonio Mantovani, Roseli G Shavitt, Marcelo Q Hoexter, Eurıpedes C Miguel and Andre R Brunoni

Background: Neuromodulation techniques for obsessive–compulsive disorder (OCD) treatment have expanded with greater understanding of the brain circuits involved. Transcranial direct current stimulation (tDCS) might be a potential new treatment for OCD, although the optimal montage is unclear. Objective: To perform a systematic review on meta-analyses of repetitive transcranianal magnetic stimulation (rTMS) and deep brain stimulation (DBS) trials for OCD, aiming to identify brain stimulation targets for future tDCS trials and to support the empirical evidence with computer head modeling analysis. Methods: Systematic reviews of rTMS and DBS trials on OCD in Pubmed/MEDLINE were searched. For the tDCS computational analysis, we employed head models with the goal of optimally targeting current delivery to structures of interest. Results: Only three references matched our eligibility criteria. We simulated four different electrodes montages and analyzed current direction and intensity. Conclusion: Although DBS, rTMS and tDCS are not directly comparable and our theoretical model, based on DBS and rTMS targets, needs empirical validation, we found that the tDCS montage with the cathode over the pre-supplementary motor area and extra-cephalic anode seems to activate most of the areas related to OCD.

Soterix Medical HDExplore used.

Khadka N, Truong DQ, Bikson, M
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Download: PDF Published in Journal of Medical Devices DOI

Abstract

Within Electrode Current Steering (WECS) is a novel method that enhances reliability and tolerability of tDCS. The underlying assumption of WECS is steering current within electrodes but without altering current distribution in brain target. Through an exemplary case example of a realistic electrode and head geometry (FEM), we demonstrated how current flow in the brain is independent of current steering at the electrode. Three current split cases (even, partially uneven, and fully uneven), keeping total current (1 mA) fixed within the electrodes are tested. At the electrode-assembly interface with the skin, the current density distribution varied only incrementally across conditions (e.g. less than would be expected with even minor changes in electrode assembly or skin properties. There was no difference in the predicted electric filed at the brain target under all three cases. Thus, with such electrode assembly design, current steering to any functional electrode would not significantly increase current density in the skin (enhance tolerability during tDCS).

Behavioral and Cognitive Neuroscience Colloquium

Friday, 10:00 AM – 11:30 AM, May 8, 2015

Room C415A, The Graduate Center, 365 5th Ave, New York, NY 10016

Lucas Parra, City College, CUNY

 “Brains on Video”

Abstract: Much of the research on human brain function studies the relationship between neural activity and specific events in the world (flashes, beeps, button pushes, and associated features such as contrast, frequency, reaction time, etc). We decided to abandon this conventional approach and look instead at responses of the brain to ongoing natural stimuli, and in particular, video. We found that when an audience watches video, their fast encephalographic brain responses are similar, however, only if the audience is paying attention! The effect is so strong that we can detect an audience’s attentional engagement in segments as short as 5 seconds. Indeed, similarity of encephalographic responses is predictive of a number of behaviors that presumably correlated with viewer’s attention, such as whether they continue watching a program, whether they ‘like’ certain ad segments, whether they decide to ‘tweet’ about it, and whether they remember the content weeks after they saw it. We believe that analyzing fast ongoing neural activity in response to natural stimuli has tremendous potential for basic inquiry into the functioning of the human brain, and has evident and important practical implications.

Special 200+ page issue of

The frontiers of clinical research on transcranial direct current stimulation (tDCS) in Neuropsychiatry

ready for FREE download here.  We our work on the cover.

Includes our article

Inter-individual variation during transcranial direct current stimulation and normalization of dose using MRI-derived computational models

Available for individual download here

BME Day, May 01, 2015, Department of Biomedical Engineering, CCNY

Wireless Pulse Oximeter (WiPOX): Its Clinical Implications and Challenges

The WiPOX provides a tool for surgeons to objectively and reliably measure tissue viability during surgery rather than rely solely on their subjective visual inspection. Tissue ischemia is a major cause of wound dehiscence or anastomotic leakage resulting in significant morbidity and mortality occuring at a rate of 15 to 25%. Although measurement of systemic blood oxygenation status by finger-tip pulse oximetery is a mandatory requirement for every anesthetized patient, there is no standadrad procedure for intra-operative measurement of internal tissue oxygenation following complex resections and reconstructions.

Based on clinical experience gained in our trials, we present here the design of a second generation WiPOX that includes a reticulated pressure-sensitive head serving two related functions. First, the often-restricted and sensitive environment in which the device is employed constrains both the angle of approach and visibility, necessitating a self- correcting reticulated swiveling head that acts to improve the contact angle between the sensor head and the tissue. Second, because the devices is hand-held, the pressure on the tissue (often a membrane) is determined by the operator; too little pressure produces poor signal to noise ratio (SNR) while too much pressure can occlude blood flow, also reducing SNR and possibly yielding erroneously low oxygenation measurements. To address this, our sensor head includes a novel mounting for multiple “balloon” style pressure sensors that provide feedback on tissue contact pressure and contact angle. The reticulated head and pressure sensor features function in tandem to improve tissue contact and ensure
reliable measurements.

VENUE: Department of Biomedical Engineering, CCNY, ST 402

Harsh Baid, 17, of Bronx Science, wrote a piece of code that allows him to navigate the world of his favorite video game by moving his eyes.His project is enhancing gaming interfaces via gaze tracking. Baid approached Professor Lucas Parra, a professor of biomedical engineering at City College, to be his mentor.

Read more

Marom Bikson gives two lectures at Albert Einstein College of Medicine (Yeshiva University)

4/17/15

Kennedy Building Room 901.  Map

2-3 PM Transcranial Direct Current Stimulation: How can one thing work for everything?

3-4 PM  How electrotherapy devices work and why they fail to reach patients.

Niranjan Khadka presented a poster at the Minnesota Neuromodulation Symposium

Poster Title: Principles of Within Electrode Current Steering(WECS)

KhadkaBiksonWECS

Department of Biomedical Engineering, The City College of New York, CUNY, 160 Convent Ave, New York, 10031, USA

Within Electrode Current Steering (WECS), a novel method, applies to non-invasive electrical stimulation with two or more electrodes to enhance reliability and tolerability during tDCS. The underlying assumption of WECS is steering current within electrodes (to compensate for any non-ideal conditions at the surface), but without altering current distribution in the brain target. This technology leverages our technique for independently isolating electrode impedance and over-potential during multi-channel stimulation. Through an exemplary case example of a realistic electrodes (metal-rivets embedded in an electrolyte (saline or gel)) and head geometry (FEM), we demonstrated how current flow in brain is independent of current steering at the electrode. Three current split cases (even, partially uneven, and fully uneven), keeping total current (1 mA) fixed within the electrodes are tested. At the electrode-assembly interface with the skin, the current density distribution varied only incrementally across conditions (e.g. less than would be expected) with even minor changes in electrode assembly or skin properties. There was no difference in the predicted electric filed at the brain target under all three cases. Thus, with such electrode assembly design, current steering to any functional electrode would not significantly increase current density in the skin; hence, not effecting tolerability.

Date & time: April 17, 2015 11:30-1:00 pm

Venue: University of Minnesota, Twin City, Minnesota

Niranjan Khadka presented a poster at the DMD Conference.

Poster Title: Design of Wireless Intraoperative Pulse Oximeter with Reticulated Pressure Sensitive Head

Link: KhadkaBiksonWiPOX

In order to provide a surgical tool that objectively and reliably measure tissue viability during surgery, we developed and validated a first generation compact handheld device for real time wireless monitoring of SPO2. Through the application of pressure sensor (provide feedback of real-time contact conditions of the device), reticulated shaft (facilitate flat contact with the tissue surface that are less visible), and systemic pulse rate input to signal tissue oxygenation through signal processing, this invention will enable surgeons to make treatment decision and measure the efficacy of the therapeutic interventions in real-time.

Date & time: April 15, 2015 5:30 – 7:00

Venue: McNamara Alumni Center, University of Minnesota, Minneapolis, MN

On the use of meta-analysis in neuromodulatory non-invasive brain stimulation

Brain Stimulation 2015 DOI: 10.1016/j.brs.2015.03.008

Michael A. Nitsche, MD, Marom Bikson, PhD, Sven Bestmann, PhD

Full PDF (in press version): MetaAnalysisinNeuromod105

In humans, non-invasive brain stimulation (NIBS) can modulate cortical excitability and activity. The buoyant use of this technique in basic and applied research requires further characterization of the basic mechanisms to divorce promising applications from those producing more heterogeneous outcomes. Here we outline some criteria and pitfalls for using published results to gain estimates about the effects of NIBS techniques through meta-analysis and related tools.

The Pursuit of DLPFC: Non-neuronavigated Methods to Target the Left Dorsolateral Pre-frontal Cortex With Symmetric Bicephalic Transcranial Direct Current Stimulation (tDCS)

Brain Stimulation 2015  doi: 10.1016/j.brs.2015.01.401

PDF (in press version): Bikson_Seibt_PursuitDLPFC_inpress2015        PubMED link

Ole Seibt, Andre R. Brunoni, Yu Huang, Marom Bikson

Abstract:  The dose of transcranial direct current stimulation (tDCS) is defined by electrode montage and current, while the resulting brain current flow is more complex and varies across individuals. The left dorsolateral pre-frontal cortex (lDLPFC) is a common target in neuropsychology and neuropsychiatry applications, with varied approaches used to experimentally position electrodes on subjects. Objective: To predict brain current flow intensity and distribution using conventional symmetrical bicephalic frontal 1
1 electrode montages to nominally target lDLPFC in forward modeling studies. Methods: Six high-resolution Finite Element Method (FEM) models were created from five subjects of varied head size and an MNI standard. Seven electrode positioning methods, nominally targeting lDLPFC, were investigated on each head model: the EEG 10-10 including F3-F4, F5-F6, F7-8, F9-F10, the Beam F3- System, the 5-5 cm-Rule and the developed OLE-System were evaluated as electrode positioning methods for 5
5 cm2 rectangular sponge-pad electrodes. Results: Each positioning approach resulted in distinct electrode positions on the scalp and variations in brain current flow. Variability was significant, but trends across montages and between subjects were identified. Factors enhancing electric field intensity and relative targeting in lDLPFC include increased inter-electrode distance and proximity to thinner skull structures. Conclusion: Brain current flow can be shaped, but not focused, across frontal cortex by tDCS montages, including intensity at lDLPFC. The OLE-system balances lDLPFC targeting and reduced electric field variability, along with clinical ease-of-use.

Full Press Release link

Antonios Mourdoukoutas, a junior majoring in biomedical engineering in the Grove School of Engineering and Macaulay Honors College at The City College of New York, has been awarded a Goldwater Scholarship for 2015.

Mourdoukoutas, who has a 3.91 GPA, is a member of Professor Marom Bikson’s lab at City College. The Long Island resident helps model methods of noninvasive brain stimulation using electrodes placed on the skin surface to correct neurological disorders or facilitate the recovery of lost motor functions.

Mourdoukoutas is the third Goldwater Scholar from Professor Marom Bikson’s lab.

Kevin T. Jones, Jaclyn A. Stephens, Mahtab Alam, Marom Bikson, Marian E. Berryhill

Published: April 7, 2015

DOI: 10.1371/journal.pone.0121904 FREE ONLINE

Abstract: An increasing concern affecting a growing aging population is working memory (WM) decline. Consequently, there is great interest in improving or stabilizing WM, which drives expanded use of brain training exercises. Such regimens generally result in temporary WM benefits to the trained tasks but minimal transfer of benefit to untrained tasks. Pairing training with neurostimulation may stabilize or improve WM performance by enhancing plasticity and strengthening WM-related cortical networks. We tested this possibility in healthy older adults. Participants received 10 sessions of sham (control) or active (anodal, 1.5 mA) tDCS to the right prefrontal, parietal, or prefrontal/parietal (alternating) cortices. After ten minutes of sham or active tDCS, participants performed verbal and visual WM training tasks. On the first, tenth, and follow-up sessions, participants performed transfer WM tasks including the spatial 2-back, Stroop, and digit span tasks. The results demonstrated that all groups benefited from WM training, as expected. However, at follow-up 1-month after training ended, only the participants in the active tDCS groups maintained significant improvement. Importantly, this pattern was observed for both trained and transfer tasks. These results demonstrate that tDCS-linked WM training can provide long-term benefits in maintaining cognitive training benefits and extending them to untrained tasks.