New Paper: tDCS in Pediatric Stroke

Pediatric Stroke and transcranial Direct Current Stimulation: Methods for Rational Individualized Dose Optimization

Bernadette T. Gillick, Adam Kirton, Jason Carmel, Preet Minhas and Marom Bikson

Front. Hum. Neurosci. | doi: 10.3389/fnhum.2014.00739

Free online

Background- Transcranial direct current stimulation (tDCS) has been investigated mainly in adults and doses may not be appropriate in pediatric applications. In perinatal stroke where potential applications are promising, rational adaptation of dosage for children remains under investigation. Objective – Construct child-specific tDCS dosing parameters through case study within a perinatal stroke tDCS safety and feasibility trial. Methods- 10-year-old subject with a diagnosis of presumed perinatal ischemic stroke and hemiparesis was identified. T1 MRI scans used to derive computerized model for current flow and electrode positions. Workflow using modeling results and consideration of dosage in previous clinical trials was incorporated. Prior Ad hoc adult montages versus de novo optimized montages provided distinct risk benefit analysis. Approximating adult dose required consideration of changes in both peak brain current flow and distribution which further tradeoff between maximizing efficacy and adding safety factors. Electrode size, position, current intensity, compliance voltage, and duration were controlled independently in this process. Results- Brain electric fields modeled and compared to values previously predicted models. Approximating conservative brain current flow patterns and intensities used in previous adult trials for comparable indications, the optimal current intensity established was 0.7 mA for 10 minutes with a tDCS C3/C4 montage. Specifically 0.7 mA produced comparable peak brain current intensity of an average adult receiving 1.0 mA. Electrode size of 5×7 cm2 with 1.0 mA and low-voltage tDCS was employed to maximize tolerability. Safety and feasibility confirmed with subject tolerating the session well and no serious adverse events. Conclusion- Rational approaches to dose customization, with steps informed by computational modeling, may improve guidance for pediatric stroke tDCS trials.


Neural Engineering
New Paper: tDCS facilitates cognitive multi-task performance

Transcranial direct current stimulation facilitates cognitive multi-task performance differentially depending on anode location and subtask 

M.Scheldrup, P.M. Greenwood, R. McKendrick, J. Strohl, M. Bikson, M. Alam, R.A.McKinley, R. Parasuraman.

Front. Hum. Neurosci. DOI: 10.3389/fnhum.2014.00665  Free ONLINE

Abstract: There is a need to facilitate acquisition of real world cognitive multi-tasks that require long periods of training (e.g., air traffic control, intelligence analysis, medicine). Non-invasive brain stimulation – specifically transcranial Direct Current Stimulation (tDCS) – has promise as a method to speed multi-task training. We hypothesized that during acquisition of the complex multi-task Space Fortress, subtasks that require focused attention on ship control would benefit from tDCS aimed at the dorsal attention network while subtasks that require redirection of attention would benefit from tDCS aimed at the right hemisphere ventral attention network. We compared effects of 30 min prefrontal and parietal stimulation to right and left hemispheres on subtask performance during the first 45 min of training. The strongest effects both overall and for ship flying (control and velocity subtasks) were seen with a right parietal (C4 to left shoulder) montage, shown by modeling to induce an electric field that includes nodes in both dorsal and ventral attention networks. This is consistent with the re-orienting hypothesis that the ventral attention network is activated along with the dorsal attention network if a new, task-relevant event occurs while visuospatial attention is focused (Corbetta et al., 2008). No effects were seen with anodes over sites that stimulated only dorsal (C3) or only ventral (F10) attention networks. The speed subtask (update memory for symbols) benefited from an F9 anode over left prefrontal cortex. These results argue for development of tDCS as a training aid in real world settings where multi-tasking is critical.

Neural Engineering
Dr. Bikson quoted in NY Times and The Atlantic

Our labs work on neuromodulation recognized in several recent press articles including:

The Atlantic. Prepare to Be Shocked. August 13, 2014

http://www.theatlantic.com/magazine/archive/2014/09/prepare-to-be-shocked/375072/

New York Times. This Procedure May Improve Your Brain — and Uncover the Real You. July 17, 2014 http://op-talk.blogs.nytimes.com/2014/07/17/this-procedure-may-improve-your-brain-and-uncover-the-real-you/

Neural Engineering
Nature Communications: Brainwaves Can Predict Audience Reaction

Media and marketing experts have long sought a reliable method of forecasting responses from the general population to future products and messages. According to a study conducted at the Neural Engineering group The City College of New York, it appears that the brain responses of just a few individuals are a remarkably strong predictor.

By analyzing the brainwaves of 16 individuals as they watched mainstream television content, researchers led by Prof. Lucas Parra were able to accurately predict the preferences of large TV audiences, up to 90 % in the case of Super Bowl commercials. The findings appear in a paper entitled, “Audience Preferences Are Predicted by Temporal Reliability of Neural Processing,” published July 29, 2014, in “Nature Communications.”

Ready Full CCNY Press Release Here

Neural Engineering
New Paper: Sham Protocols for tDCS

Title: Toward Development of Sham Protocols for High- Definition Transcranial Direct Current Stimulation (HD-tDCS) 

Jessica D. Richardson, Paul Fillmore, Abhishek Datta, Dennis Truong, Marom Bikson, Julius Fridriksson

NeuroRegulation Vol. 1(1):62-72 2014 doi:10.15540/nr.2014.1.1.62

PDF: Download

Abstract : High-definition transcranial direct current stimulation (HD-tDCS) is a noninvasive cortical
stimulation (NICS) technique that, due to the utilization of multi-electrode stimulation, may
enable development of sham conditions characterized by indistinguishable scalp sensations
compared to active conditions, with little or no cortical influence. We sought to contribute to
the development of an optimal sham electrode configuration for HD-tDCS protocols by
gathering ratings of overall sensation reported by participants during different electrode
configurations and current intensities. Twenty healthy participants completed a magnitude
estimation task during which they rated their “overall sensation” in 1-minute intervals during
five 5-minute stimulation conditions. A 5 x 5 (Time x Stimulation condition) analysis of
variance (ANOVA) was conducted to determine if sensation measurements differed over
time, and how this varied by condition. Null hypothesis significance tests and equivalence
tests were conducted to determine which sham conditions were statistically indistinguishable
from the experimental condition. The ANOVA revealed main effects for Time and Stimulation
condition. Planned comparisons, comparing each sham condition to the experimental
condition (4×1 ring configuration, 2 mA), revealed differences in sensation ratings for all but
one condition (Sham 1x1A); no sham conditions were found to be statistically equivalent to
the experimental condition. Our HD-tDCS findings build upon previous NICS reports of
differences in sensation ratings between sham versus experimental conditions when
traditional “ramping down” approaches were used. Alternative multi-electrode configurations
that manipulate electrode placement to shunt current across the scalp warrant further
investigation as valid blinding methods.

Neural Engineering
Video: Unique Engineering Education at The City College of New York – features Neural Engineering

Unique Education at Grove School of Engineering, The City College of New York – features Neural Engineering lab in BME including Dr. Simon Kelly and Dr. Marom Bikson and several students.

What makes CCNY a unique place nationally for undergraduate and gradates students to obtain training in state-of-the-art research techniques and preparation for life long learning and success.  In Dr. Bikson’s word “grit”.

Neural Engineering
Paper: Neural stimulation for the treatment of chronic pain in spinal cord injury

Targeted therapies using electrical and magnetic neural stimulation for the treatment of chronic pain in spinal cord injury

Neuroimage 85 (2014) 1003-1013

Ingrid Moreno-Duarte , Leslie R. Morse, Mahtab Alam, Marom Bikson, Ross Zafonte, Felipe Fregni

Download PDF: Bikson_targetedtherapy               Pubmed link

Chronic neuropathic pain is one of the most common and disabling symptoms in individuals with spinal cord injury (SCI). Over two-thirds of subjects with SCI suffer from chronic pain influencing quality of life, rehabilitation, and recovery. Given the refractoriness of chronic pain to most pharmacological treatments, the majority of individuals with SCI report worsening of this condition over time. Moreover, only 4–6% of patients in this cohort report improvement. Novel treatments targeting mechanisms associated with pain-maladaptive plasticity, such as electromagnetic neural stimulation, may be desirable to improve outcomes. To date, few, small clinical trials have assessed the effects of invasive and noninvasive nervous system stimulation on pain after SCI.

Neural Engineering
New Paper: Informing dose design by modeling transcutaneous spinal direct current stimulatio

Clinical Neurophysiology 2014 [epub]

PDF (pre-print) Bikson_tSDCS_model

PubMed link 

The progression of tsDCS as an effective therapeutic modality in the treatment of movement disorders and neurorehabilitation depends on a series rigorous clinical trials. With a near infinite combination of dose designs and trial protocols, the evolution of this clinical work will greatly benefit from effective tsDCS models.

See also the Soterix tsDCS device here 

Neural Engineering
Berkan Guleyupoglu is our newest MS graduate.

Today Berkan Guleyupoglu successfully defended his masters thesis!!

Abstract: Transcranial Electrical Stimulation (tES) encompasses all methods of non-invasive current application to the brain used in research and clinical practice. We present the first comprehensive and technical review, explaining the evolution of tES in both terminology and dosage over the past 100 years of research to present day. Current transcranial Pulsed Current Stimulation (tPCS) approaches such as Cranial Electrotherapy Stimulation (CES) descended from Electrosleep (ES) through Cranial Electro-stimulation Therapy (CET), Transcerebral Electrotherapy (TCET), and NeuroElectric Therapy (NET) while others like Transcutaneous Cranial Electrical Stimulation (TCES) descended from Electroanesthesia (EA) through Limoge, and Interferential Stimulation. Prior to a contemporary resurgence in interest, variations of transcranial Direct Current Stimulation were explored intermittently, including Polarizing current, Galvanic Vestibular Stimulation (GVS), and Transcranial Micropolarization. The development of these approaches alongside Electroconvulsive Therapy (ECT) and pharmacological developments are considered. Both the roots and unique features of contemporary approaches such as transcranial Alternating Current Stimulation (tACS) and transcranial Random Noise Stimulation (tRNS) are discussed. Trends and incremental developments in electrode montage and waveform spanning decades are presented leading to the present day. Commercial devices, seminal conferences, and regulatory decisions are noted. This is concluded with six rules on how increasing medical and technological sophistication may now be leveraged for broader success and adoption of tES.

Despite this history, questions regarding the efficacy of ES remain including optimal dose (electrode placement and waveform). An investigation into brain electric field and current density produced by various montages that are historically relevant to ES was done to evaluate how these montages effect the brain. MRI-derived head models that were segmented using an automated segmentation algorithm and manual corrections were solved for four different electrode montages. The montages that were used are as follows: Sponge electrode on left and right eyes (active), Sponge electrodes over left and right mastoids (return); Sponge electrodes above left and right eyes (active), Sponge electrodes over left and right mastoids (return); High-Definition (HD) electrodes on AF3 and AF4 (active), 5×7 cm sponge on neck (return); HD electrodes on AF3 and AF4 (active), 5×7 sponge electrode on Iz (return). A high concentration of electric field was found on the optic nerve, with levels lowered as the electrodes moved further away from the eyes. There was also a moderate current density on the amygdala, a center involved with anxiety, as well as high electric fields on the brain stem which are centers for sleep.

Neural Engineering
Bikson Lab awarded two NIH grants on Medical Device Design

R21 (2 years): Modulation of blood-brain-barrier (BBB) permeability by tDCS relevant electric fields

Transcranial Direct Current Stimulation (tDCS) is a non-invasive electrical stimulation technique investigated for a broad range of medical and performance indications. Understanding the cellular mechanisms of tDCS will increase the rigor of ongoing studies and provide a rational basis for dose optimization. Prior mechanistic studies have focused exclusively on direct polarization of neuronal membranes by direct current stimulation (DCS). We propose to test the hypothesis that tDCS directly and transiently modulates blood-brain-barrier (BBB) function, which in turn would modulate neuronal activity. Our approach is to use state-of-the-art animal and tissue models and characterization to determine if a new-class of cellular targets, namely endothelial cells, respond to DCS. These approaches including multi-photon transcranial quantitative imaging of vascular permeability during and after DCS and isolation of molecular and generic responses of endothelial barriers. Because understanding every cellular target of stimulation is required for a comprehensive mechanism, the modulation of BBB by tDCS, in conjunction with direct neuronal effects, is novel and critical to research. This study will be the first to establish the feasibility of direct BBB actions by tDCS as well as quantitatively predict the impact of these changes on neuronal function.

R03 (one year): Wireless Pulse Oximetry (WiPOX) for Diagnosing Intra-Operative Ischemia

Tissue ischemia is a major cause of wound dehiscence or anastomotic leakage
resulting in significant morbidity and mortality and occurs at a rate of 15 to 25%. Although
measurement of systemic blood oxygenation status by pulse oximetry on the finger is a
mandatory requirement for every single patient while in the hospital, there are no devices or
methods available to measure tissue oxygenation following complex surgical resections and
reconstructions in the operating room. Increasingly, surgical procedures are performed by
minimally invasive techniques, which add complexity to the problem, as surgeons do not have
the opportunity to directly touch, feel or visualize the organs. In a collaboration between The
City College of New York (CCNY) bioengineering design team and Memorial Sloan-Kettering
Cancer Center (MSKCC) surgeons, we have successfully designed, constructed and tested a
novel wireless, handheld intraoperative oximetry (WiPOX) device, which provides real-time,
accurate, and convenient intraoperative monitoring of the tissue oxygenation ensuring tissue
viability thereby improving surgical outcomes, decreasing mortality, patient hospitalization and
the associated costs. In this R03 proposal, based on the feedback from the ongoing clinical trial,
we will enhance device performance and accuracy through two further innovations:
incorporation of onboard pressure sensors to allow reliable tissue contact and enhancement of
S/N through wireless integration with a systemic pulse oximeter. A pipeline for preclinical and
clinical testing is in place. These innovative modifications are crucial for surgeons to take the
next step of this device utility – to modify the surgical procedure based on tissue oxygenation

Neural Engineering