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Meinzer M, Shahbabaie A, Antonenko D, Blankenburg F, Fischer R, Hartwigsen G, Nitsche MA, Li SC, Thielscher A, Timmann D, Waltemath D, Abdelmotaleb M, Kocataş H, Caisachana Guevara LM, Batsikadze G, Grundei M, Cunha T, Hayek D, Turker S, Schlitt F, Shi Y, Khan A, Burke M, Riemann S, Niemann F, Flöel A. Investigating the neural mechanisms of transcranial direct current stimulation effects on human cognition: current issues and potential solutions. Front Neurosci 2024; 18:1389651. [PMID: 38957187 PMCID: PMC11218740 DOI: 10.3389/fnins.2024.1389651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Accepted: 05/15/2024] [Indexed: 07/04/2024] Open
Abstract
Transcranial direct current stimulation (tDCS) has been studied extensively for its potential to enhance human cognitive functions in healthy individuals and to treat cognitive impairment in various clinical populations. However, little is known about how tDCS modulates the neural networks supporting cognition and the complex interplay with mediating factors that may explain the frequently observed variability of stimulation effects within and between studies. Moreover, research in this field has been characterized by substantial methodological variability, frequent lack of rigorous experimental control and small sample sizes, thereby limiting the generalizability of findings and translational potential of tDCS. The present manuscript aims to delineate how these important issues can be addressed within a neuroimaging context, to reveal the neural underpinnings, predictors and mediators of tDCS-induced behavioral modulation. We will focus on functional magnetic resonance imaging (fMRI), because it allows the investigation of tDCS effects with excellent spatial precision and sufficient temporal resolution across the entire brain. Moreover, high resolution structural imaging data can be acquired for precise localization of stimulation effects, verification of electrode positions on the scalp and realistic current modeling based on individual head and brain anatomy. However, the general principles outlined in this review will also be applicable to other imaging modalities. Following an introduction to the overall state-of-the-art in this field, we will discuss in more detail the underlying causes of variability in previous tDCS studies. Moreover, we will elaborate on design considerations for tDCS-fMRI studies, optimization of tDCS and imaging protocols and how to assure high-level experimental control. Two additional sections address the pressing need for more systematic investigation of tDCS effects across the healthy human lifespan and implications for tDCS studies in age-associated disease, and potential benefits of establishing large-scale, multidisciplinary consortia for more coordinated tDCS research in the future. We hope that this review will contribute to more coordinated, methodologically sound, transparent and reproducible research in this field. Ultimately, our aim is to facilitate a better understanding of the underlying mechanisms by which tDCS modulates human cognitive functions and more effective and individually tailored translational and clinical applications of this technique in the future.
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Affiliation(s)
- Marcus Meinzer
- Department of Neurology, University Medicine Greifswald, Greifswald, Germany
| | - Alireza Shahbabaie
- Department of Neurology, University Medicine Greifswald, Greifswald, Germany
| | - Daria Antonenko
- Department of Neurology, University Medicine Greifswald, Greifswald, Germany
| | - Felix Blankenburg
- Neurocomputation and Neuroimaging Unit, Department of Education and Psychology, Freie Universität Berlin, Berlin, Germany
| | - Rico Fischer
- Department of Psychology, University of Greifswald, Greifswald, Germany
| | - Gesa Hartwigsen
- Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
- Wilhelm Wundt Institute for Psychology, Leipzig University, Leipzig, Germany
| | - Michael A. Nitsche
- Department of Psychology and Neurosciences, Leibniz Research Centre for Working Environment and Human Factors at TU Dortmund, Dortmund, Germany
- German Center for Mental Health (DZPG), Bochum, Germany
- Bielefeld University, University Hospital OWL, Protestant Hospital of Bethel Foundation, University Clinic of Psychiatry and Psychotherapy, Bielefeld, Germany
| | - Shu-Chen Li
- Chair of Lifespan Developmental Neuroscience, Faculty of Psychology, Technische Universität Dresden, Dresden, Germany
| | - Axel Thielscher
- Section for Magnetic Resonance, Department of Health Technology, Technical University of Denmark, Kongens Lyngby, Denmark
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Amager and Hvidovre, Copenhagen, Denmark
| | - Dagmar Timmann
- Department of Neurology and Center for Translational Neuro- and Behavioral Sciences (C-TNBS), Essen University Hospital, University of Duisburg-Essen, Essen, Germany
| | - Dagmar Waltemath
- Core Unit Data Integration Center, University Medicine Greifswald, Greifswald, Germany
| | | | - Harun Kocataş
- Department of Neurology, University Medicine Greifswald, Greifswald, Germany
| | | | - Giorgi Batsikadze
- Department of Neurology and Center for Translational Neuro- and Behavioral Sciences (C-TNBS), Essen University Hospital, University of Duisburg-Essen, Essen, Germany
| | - Miro Grundei
- Neurocomputation and Neuroimaging Unit, Department of Education and Psychology, Freie Universität Berlin, Berlin, Germany
| | - Teresa Cunha
- Section for Magnetic Resonance, Department of Health Technology, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Dayana Hayek
- Department of Neurology, University Medicine Greifswald, Greifswald, Germany
| | - Sabrina Turker
- Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
- Wilhelm Wundt Institute for Psychology, Leipzig University, Leipzig, Germany
| | - Frederik Schlitt
- Department of Neurology and Center for Translational Neuro- and Behavioral Sciences (C-TNBS), Essen University Hospital, University of Duisburg-Essen, Essen, Germany
| | - Yiquan Shi
- Chair of Lifespan Developmental Neuroscience, Faculty of Psychology, Technische Universität Dresden, Dresden, Germany
| | - Asad Khan
- Department of Psychology and Neurosciences, Leibniz Research Centre for Working Environment and Human Factors at TU Dortmund, Dortmund, Germany
| | - Michael Burke
- Department of Psychology and Neurosciences, Leibniz Research Centre for Working Environment and Human Factors at TU Dortmund, Dortmund, Germany
| | - Steffen Riemann
- Department of Neurology, University Medicine Greifswald, Greifswald, Germany
| | - Filip Niemann
- Department of Neurology, University Medicine Greifswald, Greifswald, Germany
| | - Agnes Flöel
- Department of Neurology, University Medicine Greifswald, Greifswald, Germany
- German Center for Neurodegenerative Diseases (DZNE Site Greifswald), Greifswald, Germany
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Wu PJ, Huang CH, Lee SY, Chang AYW, Wang WC, Lin CCK. The distinct and potentially conflicting effects of tDCS and tRNS on brain connectivity, cortical inhibition, and visuospatial memory. Front Hum Neurosci 2024; 18:1415904. [PMID: 38873654 PMCID: PMC11169625 DOI: 10.3389/fnhum.2024.1415904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Accepted: 05/13/2024] [Indexed: 06/15/2024] Open
Abstract
Noninvasive brain stimulation (NIBS) techniques, including transcranial direct current stimulation (tDCS) and transcranial random noise stimulation (tRNS), are emerging as promising tools for enhancing cognitive functions by modulating brain activity and enhancing cognitive functions. Despite their potential, the specific and combined effects of tDCS and tRNS on brain functions, especially regarding functional connectivity, cortical inhibition, and memory performance, are not well-understood. This study aims to explore the distinct and combined impacts of tDCS and tRNS on these neural and cognitive parameters. Using a within-subject design, ten participants underwent four stimulation conditions: sham, tDCS, tRNS, and combined tDCS + tRNS. We assessed the impact on resting-state functional connectivity, cortical inhibition via Cortical Silent Period (CSP), and visuospatial memory performance using the Corsi Block-tapping Test (CBT). Our results indicate that while tDCS appears to induce brain lateralization, tRNS has more generalized and dispersive effects. Interestingly, the combined application of tDCS and tRNS did not amplify these effects but rather suggested a non-synergistic interaction, possibly due to divergent mechanistic pathways, as observed across fMRI, CSP, and CBT measures. These findings illuminate the complex interplay between tDCS and tRNS, highlighting their non-additive effects when used concurrently and underscoring the necessity for further research to optimize their application for cognitive enhancement.
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Affiliation(s)
- Pei-Jung Wu
- Department of Neurology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Chih-Hsu Huang
- Department of Neurology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Shuenn-Yuh Lee
- Department of Electrical Engineering, National Cheng Kung University, Tainan, Taiwan
| | - Alice Y. W. Chang
- Department of Physiology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Wen-Chi Wang
- Department of Neurology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Chou-Ching K. Lin
- Department of Neurology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
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Rajagopalan NR, Vista WR, Fujimori M, Vroomen LGPH, Jiménez JM, Khadka N, Bikson M, Srimathveeravalli G. Cytoskeletal Remodeling and Gap Junction Translocation Mediates Blood-Brain Barrier Disruption by Non-invasive Low-Voltage Pulsed Electric Fields. Ann Biomed Eng 2024; 52:89-102. [PMID: 37115366 DOI: 10.1007/s10439-023-03211-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Accepted: 04/14/2023] [Indexed: 04/29/2023]
Abstract
High-voltage pulsed electric fields (HV-PEF) delivered with invasive needle electrodes for electroporation applications is known to induce off-target blood-brain barrier (BBB) disruption. In this study, we sought to determine the feasibility of minimally invasive PEF application to produce BBB disruption in rat brain and identify the putative mechanisms mediating the effect. We observed dose-dependent presence of Evans Blue (EB) dye in rat brain when PEF were delivered with a skull mounted electrode used for neurostimulation application. Maximum region of dye uptake was observed while using 1500 V, 100 pulses, 100 µs and 10 Hz. Results of computational models suggested that the region of BBB disruption was occurring at thresholds of 63 V/cm or higher; well below intensity levels for electroporation. In vitro experiments recapitulating this effect with human umbilical vein endothelial cells (HUVEC) demonstrated cellular alterations that underlie BBB manifests at low-voltage high-pulse conditions without affecting cell viability or proliferation. Morphological changes in HUVECs due to PEF were accompanied by disruption of actin cytoskeleton, loss of tight junction protein-ZO-1 and VE-Cadherin at cell junctions and partial translocation into the cytoplasm. Uptake of propidium iodide (PI) in PEF treated conditions is less than 1% and 2.5% of total number of cells in high voltage (HV) and low-voltage (LV) groups, respectively, implying that BBB disruption to be independent of electroporation under these conditions. 3-D microfabricated blood vessel permeability was found to increase significantly following PEF treatment and confirmed with correlative cytoskeletal changes and loss of tight junction proteins. Finally, we show that the rat brain model can be scaled to human brains with a similar effect on BBB disruption characterized by electric field strength (EFS) threshold and using a combination of two bilateral HD electrode configurations.
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Affiliation(s)
| | - William-Ray Vista
- Department of Radiology, Interventional Radiology Service, Memorial Sloan-Kettering Cancer Center, New York, NY, USA
| | - Masashi Fujimori
- Department of Radiology, Interventional Radiology Service, Memorial Sloan-Kettering Cancer Center, New York, NY, USA
- Department of Radiology, Mie University, Tsu, Mie, Japan
| | | | - Juan M Jiménez
- Department of Mechanical and Industrial Engineering, University of Massachusetts Amherst, Amherst, MA, USA
| | - Niranjan Khadka
- Division of Neuromodulation, Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
- Synchron Inc, Brooklyn, NY, USA
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA
| | - Marom Bikson
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA
| | - Govindarajan Srimathveeravalli
- Department of Mechanical and Industrial Engineering, University of Massachusetts Amherst, Amherst, MA, USA.
- Institute for Applied Life Sciences, University of Massachusetts Amherst, Amherst, MA, USA.
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Hsu WY, Zanto T, Park JE, Gazzaley A, Bove RM. Effects of transcranial alternating current stimulation on cognitive function in people with multiple sclerosis: A randomized controlled trial. Mult Scler Relat Disord 2023; 80:105090. [PMID: 37925960 DOI: 10.1016/j.msard.2023.105090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 09/14/2023] [Accepted: 10/18/2023] [Indexed: 11/07/2023]
Abstract
BACKGROUND Cognitive impairment is a core symptom that profoundly impacts the lives of people with multiple sclerosis (PwMS). Since the existing disease modifying therapies can only stabilize, but not actively treat, cognition in PwMS, there is an unmet need to expand approaches to treat these cognitive symptoms. Transcranial alternating current stimulation (tACS) permits frequency-specific entrainment of neural oscillations intrinsic to cognitive activity. However, the effects of the tACS on cognitive function in PwMS have not yet been assessed. We aimed to evaluate the potential efficacy of applying frontal theta-tACS to improve information processing speed in PwMS. METHODS 60 PwMS with cognitive complaints were enrolled in a double-blinded, randomized, controlled trial with three stimulation groups: 2 mA, 1 mA, or sham control. A single session of theta-tACS was applied while participants were engaged in a cognitive program which has shown to improve processing speed in PwMS. tACS effects were examined by the Symbol Digit Modalities Test (SDMT). Tolerability, side effects and acceptability were measured. RESULTS 1 mA groups had a significantly higher SDMT score after stimulation compared to their pre-stimulation score, 2 mA group showed a marginally significant improvement of their SDMT score, while the SDMT score in the sham group did not change. Overall, 49% of the stimulation group participants showed a clinically meaningful SDMT improvement (4+-point increase). CONCLUSION tACS is a well-tolerated, non-pharmacological intervention. Based on the positive effects observed in the current study of a single session of tACS applied during cognitive engagement, the effects of repeated tACS on cognitive function in PwMS merit further research. TRIAL REGISTRATION ClinicalTrials.gov NCT04466228.
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Affiliation(s)
- Wan-Yu Hsu
- UCSF Weill Institute for Neurosciences, Department of Neurology, University of California, 1651 4th St, San Francisco, CA 94158, USA.
| | - Theodore Zanto
- UCSF Weill Institute for Neurosciences, Department of Neurology, University of California, 1651 4th St, San Francisco, CA 94158, USA; Neuroscape, University of California San Francisco, San Francisco, CA, USA
| | - Jee Eun Park
- UCSF Weill Institute for Neurosciences, Department of Neurology, University of California, 1651 4th St, San Francisco, CA 94158, USA; Neuroscape, University of California San Francisco, San Francisco, CA, USA; Department of Psychiatry, Seoul National University College of Medicine and Seoul National University Hospital, Seoul, South Korea
| | - Adam Gazzaley
- UCSF Weill Institute for Neurosciences, Department of Neurology, University of California, 1651 4th St, San Francisco, CA 94158, USA; Neuroscape, University of California San Francisco, San Francisco, CA, USA
| | - Riley M Bove
- UCSF Weill Institute for Neurosciences, Department of Neurology, University of California, 1651 4th St, San Francisco, CA 94158, USA
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Khalil R, Karim AA, Godde B. Less might be more: 1 mA but not 1.5 mA of tDCS improves tactile orientation discrimination. IBRO Neurosci Rep 2023; 15:186-192. [PMID: 37746157 PMCID: PMC10511473 DOI: 10.1016/j.ibneur.2023.08.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 08/08/2023] [Accepted: 08/17/2023] [Indexed: 09/26/2023] Open
Abstract
Background Transcranial direct current stimulation (tDCS) is a frequently used brain stimulation method; however, studies on tactile perception using tDCS are inconsistent, which might be explained by the variations in endogenous and exogenous parameters that influence tDCS. Objectives We aimed to investigate the effect of one of these endogenous parameters-the tDCS amplitude-on tactile perception. Methods We conducted this experiment on 28 undergraduates/graduates aged 18-36 years. In separate sessions, participants received 20 min of 1 mA or 1.5 mA current tDCS in a counterbalanced order. Half of the participants received anodal tDCS of the left SI coupled with cathodal tDCS of the right SI, and this montage was reversed for the other half. Pre- and post-tDCS tactile discrimination performance was assessed using the Grating Orientation Task (GOT). In this task, plastic domes with gratings of different widths cut into their surfaces are placed on the fingertip, and participants have to rate the orientation of the gratings. Results Linear modeling with amplitude, dome, and session as within factors and montage as between factors revealed the following: significant main effects of grating width, montage, and session and a marginally significant interaction effect of session and amplitude. Posthoc t-tests indicated that performance in GOT improved after 1 mA but not 1.5 mA tDCS independent of the montage pattern of the electrodes. Conclusion Increasing the stimulation amplitude from 1 mA to 1.5 mA does not facilitate the tDCS effect on GOT performance. On the contrary, the effect seemed more robust for the lower-current amplitude.
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Affiliation(s)
- Radwa Khalil
- School of Business, Social and Decision Sciences, Constructor University, Bremen, Germany
| | - Ahmed A. Karim
- School of Business, Social and Decision Sciences, Constructor University, Bremen, Germany
- Department of Psychiatry and Psychotherapy, University Clinic Tübingen, Tübingen, Germany
- Department of Health Psychology and Neurorehabilitation, SRH Mobile University, Riedlingen, Germany
| | - Ben Godde
- School of Business, Social and Decision Sciences, Constructor University, Bremen, Germany
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Farahani F, Khadka N, Parra LC, Bikson M, Vöröslakos M. Transcranial electric stimulation modulates firing rate at clinically relevant intensities. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.24.568618. [PMID: 38045400 PMCID: PMC10690262 DOI: 10.1101/2023.11.24.568618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Notwithstanding advances with low-intensity transcranial electrical stimulation (TES), there remain questions about the efficacy of clinically realistic electric fields on neuronal function. We used Neuropixels 2.0 probe with 384 channels in an in-vivo rat model of TES to detect effects of weak fields on neuronal firing rate. High-density field mapping and computational models verified field intensity (1 V/m in hippocampus per 50 μA of applied skull currents). We demonstrate that electric fields below 0.5 V/m acutely modulate firing rate in 5% of neurons recorded in the hippocampus. At these intensities, average firing rate effects increased monotonically with electric field intensity at a rate of 7 % per V/m. For the majority of excitatory neurons, firing increased for cathodal stimulation and diminished for anodal stimulation. While more diverse, the response of inhibitory neurons followed a similar pattern on average, likely as a result of excitatory drive. Our results indicate that responses to TES at clinically relevant intensities are driven by a fraction of high-responder excitatory neurons, with polarity-specific effects. We conclude that transcranial electric stimulation is an effective neuromodulator at clinically realistic intensities.
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Affiliation(s)
- Forouzan Farahani
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA
| | - Niranjan Khadka
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA
| | - Lucas C. Parra
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA
| | - Marom Bikson
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA
| | - Mihály Vöröslakos
- Neuroscience Institute and Department of Neurology, NYU Grossman School of Medicine, New York University, New York, NY, USA
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Zhou Y, Xia X, Zhao X, Yang R, Wu Y, Liu J, Lyu X, Li Z, Zhang G, Du X. Efficacy and safety of Transcranial Direct Current Stimulation (tDCS) on cognitive function in chronic schizophrenia with Tardive Dyskinesia (TD): a randomized, double-blind, sham-controlled, clinical trial. BMC Psychiatry 2023; 23:623. [PMID: 37620825 PMCID: PMC10464035 DOI: 10.1186/s12888-023-05112-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 08/14/2023] [Indexed: 08/26/2023] Open
Abstract
OBJECTIVE Previous studies have shown that transcranial direct current stimulation(tDCS) led to an improvement of cognitive function in patients with schizophrenia, but rare study has explored the effect of tDCS on long-term hospitalized chronic schizophrenia with tardive dyskinesia (TD). The present research explored if cognitive function in patients with long-term hospitalized chronic schizophrenia with TD could be improved through tDCS. METHODS This study is a randomized, double-blind, sham-controlled clinical trial. Of the 52 patients, 14 dropped out, and 38 completed the experiment. Thirty-eight patients on stable treatment regimens were randomly assigned to receive active tDCS(n = 21) or sham stimulation(n = 17) on weekdays of the first, third, and fifth weeks of treatment. Patients performed the Pattern Recognition Memory (PRM) and the Intra/Extradimensional Set Shift (IED) from the Cambridge Neuropsychological Test Automated Battery (CANTAB) at baseline and the end of week 3, week 5. Clinical symptoms were also measured at the baseline and the fifth week using the Scale for the Assessment of Negative Symptoms (SANS) and the Positive and Negative Syndrome Scale (PANSS). Side effects of tDCS were assessed with an experimenter-administered open-ended questionnaire during the whole experiment. RESULTS There were no significant differences in PRM and IED performance metrics, SANS total score and PANSS total score between active and sham tDCS groups at the end of week 5 (p > 0.05). Furthermore, there was a significant difference in the adverse effects of the tingling sensation between the two groups (p < 0.05), but there was no significant difference in other side effects (p > 0.05). CONCLUSION According to these findings, no evidence supports using anodal stimulation over the left dorsolateral prefrontal cortex to improve cognitive function in patients with long-term hospitalized chronic schizophrenia with TD.
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Affiliation(s)
- Yue Zhou
- Xuzhou Medical University, Xuzhou, China
- Suzhou Guangji Hospital, The Affiliated Guangji Hospital of Soochow University, Suzhou, China
| | - Xingzhi Xia
- Xuzhou Medical University, Xuzhou, China
- Suzhou Guangji Hospital, The Affiliated Guangji Hospital of Soochow University, Suzhou, China
| | - Xueli Zhao
- Suzhou Guangji Hospital, The Affiliated Guangji Hospital of Soochow University, Suzhou, China
| | - Ruchang Yang
- Suzhou Guangji Hospital, The Affiliated Guangji Hospital of Soochow University, Suzhou, China
- Medical College of Soochow University, Suzhou, China
| | - Yuxuan Wu
- Suzhou Guangji Hospital, The Affiliated Guangji Hospital of Soochow University, Suzhou, China
- Medical College of Soochow University, Suzhou, China
| | - Junjun Liu
- Nanjing Meishan Hospital, Nanjing, China
| | - Xiaoli Lyu
- Affiliated WuTaiShan Hospital of Medical College of Yangzhou University, Yangzhou, China
| | - Zhe Li
- Suzhou Guangji Hospital, The Affiliated Guangji Hospital of Soochow University, Suzhou, China
| | - Guangya Zhang
- Suzhou Guangji Hospital, The Affiliated Guangji Hospital of Soochow University, Suzhou, China
| | - Xiangdong Du
- Xuzhou Medical University, Xuzhou, China.
- Suzhou Guangji Hospital, The Affiliated Guangji Hospital of Soochow University, Suzhou, China.
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Liang L, Damiani A, Del Brocco M, Rogers ER, Jantz MK, Fisher LE, Gaunt RA, Capogrosso M, Lempka SF, Pirondini E. A systematic review of computational models for the design of spinal cord stimulation therapies: from neural circuits to patient-specific simulations. J Physiol 2023; 601:3103-3121. [PMID: 36409303 PMCID: PMC10259770 DOI: 10.1113/jp282884] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 11/08/2022] [Indexed: 08/02/2023] Open
Abstract
Seventy years ago, Hodgkin and Huxley published the first mathematical model to describe action potential generation, laying the foundation for modern computational neuroscience. Since then, the field has evolved enormously, with studies spanning from basic neuroscience to clinical applications for neuromodulation. Computer models of neuromodulation have evolved in complexity and personalization, advancing clinical practice and novel neurostimulation therapies, such as spinal cord stimulation. Spinal cord stimulation is a therapy widely used to treat chronic pain, with rapidly expanding indications, such as restoring motor function. In general, simulations contributed dramatically to improve lead designs, stimulation configurations, waveform parameters and programming procedures and provided insight into potential mechanisms of action of electrical stimulation. Although the implementation of neural models are relentlessly increasing in number and complexity, it is reasonable to ask whether this observed increase in complexity is necessary for improved accuracy and, ultimately, for clinical efficacy. With this aim, we performed a systematic literature review and a qualitative meta-synthesis of the evolution of computational models, with a focus on complexity, personalization and the use of medical imaging to capture realistic anatomy. Our review showed that increased model complexity and personalization improved both mechanistic and translational studies. More specifically, the use of medical imaging enabled the development of patient-specific models that can help to transform clinical practice in spinal cord stimulation. Finally, we combined our results to provide clear guidelines for standardization and expansion of computational models for spinal cord stimulation.
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Affiliation(s)
- Lucy Liang
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- Rehab Neural Engineering Labs, University of Pittsburgh, Pittsburgh, PA, USA
- Center for the Neural Basis of Cognition, Pittsburgh, PA, USA
| | - Arianna Damiani
- Rehab Neural Engineering Labs, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, USA
| | - Matteo Del Brocco
- Rehab Neural Engineering Labs, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, USA
| | - Evan R Rogers
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, USA
| | - Maria K Jantz
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- Rehab Neural Engineering Labs, University of Pittsburgh, Pittsburgh, PA, USA
- Center for the Neural Basis of Cognition, Pittsburgh, PA, USA
| | - Lee E Fisher
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- Rehab Neural Engineering Labs, University of Pittsburgh, Pittsburgh, PA, USA
- Center for the Neural Basis of Cognition, Pittsburgh, PA, USA
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, USA
| | - Robert A Gaunt
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- Rehab Neural Engineering Labs, University of Pittsburgh, Pittsburgh, PA, USA
- Center for the Neural Basis of Cognition, Pittsburgh, PA, USA
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, USA
| | - Marco Capogrosso
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- Rehab Neural Engineering Labs, University of Pittsburgh, Pittsburgh, PA, USA
- Center for the Neural Basis of Cognition, Pittsburgh, PA, USA
- Department of Neurological Surgery, University of Pittsburgh, Pittsburgh, PA, USA
| | - Scott F Lempka
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, USA
- Department of Anesthesiology, University of Michigan, Ann Arbor, MI, USA
| | - Elvira Pirondini
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- Rehab Neural Engineering Labs, University of Pittsburgh, Pittsburgh, PA, USA
- Center for the Neural Basis of Cognition, Pittsburgh, PA, USA
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, USA
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Unal G, Poon C, FallahRad M, Thahsin M, Argyelan M, Bikson M. Quasi-static pipeline in electroconvulsive therapy computational modeling. Brain Stimul 2023; 16:607-618. [PMID: 36933652 PMCID: PMC10988926 DOI: 10.1016/j.brs.2023.03.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 03/09/2023] [Accepted: 03/14/2023] [Indexed: 03/18/2023] Open
Abstract
BACKGROUND Computational models of current flow during Electroconvulsive Therapy (ECT) rely on the quasi-static assumption, yet tissue impedance during ECT may be frequency specific and change adaptively to local electric field intensity. OBJECTIVES We systematically consider the application of the quasi-static pipeline to ECT under conditions where 1) static impedance is measured before ECT and 2) during ECT when dynamic impedance is measured. We propose an update to ECT modeling accounting for frequency-dependent impedance. METHODS The frequency content on an ECT device output is analyzed. The ECT electrode-body impedance under low-current conditions is measured with an impedance analyzer. A framework for ECT modeling under quasi-static conditions based on a single device-specific frequency (e.g., 1 kHz) is proposed. RESULTS Impedance using ECT electrodes under low-current is frequency dependent and subject specific, and can be approximated at >100 Hz with a subject-specific lumped parameter circuit model but at <100 Hz increased non-linearly. The ECT device uses a 2 μA 800 Hz test signal and reports a static impedance that approximate 1 kHz impedance. Combined with prior evidence suggesting that conductivity does not vary significantly across ECT output frequencies at high-currents (800-900 mA), we update the adaptive pipeline for ECT modeling centered at 1 kHz frequency. Based on individual MRI and adaptive skin properties, models match static impedance (at 2 μA) and dynamic impedance (at 900 mA) of four ECT subjects. CONCLUSIONS By considering ECT modeling at a single representative frequency, ECT adaptive and non-adaptive modeling can be rationalized under a quasi-static pipeline.
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Affiliation(s)
- Gozde Unal
- Department of Biomedical Engineering, The City College of New York, CUNY, New York, NY, USA.
| | - Cynthia Poon
- Department of Biomedical Engineering, The City College of New York, CUNY, New York, NY, USA
| | - Mohamad FallahRad
- Department of Biomedical Engineering, The City College of New York, CUNY, New York, NY, USA
| | - Myesha Thahsin
- Department of Biomedical Engineering, The City College of New York, CUNY, New York, NY, USA
| | - Miklos Argyelan
- Center for Neurosciences, The Feinstein Institute for Medical Research, North Shore- Long Island Jewish Health System, Manhasset, NY, 11030, USA
| | - Marom Bikson
- Department of Biomedical Engineering, The City College of New York, CUNY, New York, NY, USA.
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10
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Sawai S, Murata S, Fujikawa S, Yamamoto R, Shima K, Nakano H. Effects of neurofeedback training combined with transcranial direct current stimulation on motor imagery: A randomized controlled trial. Front Neurosci 2023; 17:1148336. [PMID: 36937688 PMCID: PMC10017549 DOI: 10.3389/fnins.2023.1148336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 02/16/2023] [Indexed: 03/06/2023] Open
Abstract
Introduction Neurofeedback (NFB) training and transcranial direct current stimulation (tDCS) have been shown to individually improve motor imagery (MI) abilities. However, the effect of combining both of them with MI has not been verified. Therefore, the aim of this study was to examine the effect of applying tDCS directly before MI with NFB. Methods Participants were divided into an NFB group (n = 10) that performed MI with NFB and an NFB + tDCS group (n = 10) that received tDCS for 10 min before MI with NFB. Both groups performed 60 MI trials with NFB. The MI task was performed 20 times without NFB before and after training, and μ-event-related desynchronization (ERD) and vividness MI were evaluated. Results μ-ERD increased significantly in the NFB + tDCS group compared to the NFB group. MI vividness significantly increased before and after training. Discussion Transcranial direct current stimulation and NFB modulate different processes with respect to MI ability improvement; hence, their combination might further improve MI performance. The results of this study indicate that the combination of NFB and tDCS for MI is more effective in improving MI abilities than applying them individually.
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Affiliation(s)
- Shun Sawai
- Graduate School of Health Sciences, Kyoto Tachibana University, Kyoto, Japan
- Department of Rehabilitation, Kyoto Kuno Hospital, Kyoto, Japan
| | - Shin Murata
- Graduate School of Health Sciences, Kyoto Tachibana University, Kyoto, Japan
- Department of Physical Therapy, Faculty of Health Sciences, Kyoto Tachibana University, Kyoto, Japan
| | - Shoya Fujikawa
- Department of Physical Therapy, Faculty of Health Sciences, Kyoto Tachibana University, Kyoto, Japan
| | - Ryosuke Yamamoto
- Department of Rehabilitation, Tesseikai Neurosurgical Hospital, Shijonawate, Japan
| | - Keisuke Shima
- Graduate School of Environment and Information Sciences, Yokohama National University, Yokohama, Japan
| | - Hideki Nakano
- Graduate School of Health Sciences, Kyoto Tachibana University, Kyoto, Japan
- Department of Physical Therapy, Faculty of Health Sciences, Kyoto Tachibana University, Kyoto, Japan
- *Correspondence: Hideki Nakano,
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11
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Khadka N, Bikson M. Neurocapillary-Modulation. Neuromodulation 2022; 25:1299-1311. [PMID: 33340187 PMCID: PMC8213863 DOI: 10.1111/ner.13338] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Revised: 11/05/2020] [Accepted: 11/23/2020] [Indexed: 02/06/2023]
Abstract
OBJECTIVES We consider two consequences of brain capillary ultrastructure in neuromodulation. First, blood-brain barrier (BBB) polarization as a consequence of current crossing between interstitial space and the blood. Second, interstitial current flow distortion around capillaries impacting neuronal stimulation. MATERIALS AND METHODS We developed computational models of BBB ultrastructure morphologies to first assess electric field amplification at the BBB (principle 1) and neuron polarization amplification by the presence of capillaries (principle 2). We adapt neuron cable theory to develop an analytical solution for maximum BBB polarization sensitivity. RESULTS Electrical current crosses between the brain parenchyma (interstitial space) and capillaries, producing BBB electric fields (EBBB) that are >400x of the average parenchyma electric field (ĒBRAIN), which in turn modulates transport across the BBB. Specifically, for a BBB space constant (λBBB) and wall thickness (dth-BBB), the analytical solution for maximal BBB electric field (EABBB) is given as: (ĒBRAIN × λBBB)/dth-BBB. Electrical current in the brain parenchyma is distorted around brain capillaries, amplifying neuronal polarization. Specifically, capillary ultrastructure produces ∼50% modulation of the ĒBRAIN over the ∼40 μm inter-capillary distance. The divergence of EBRAIN (Activating function) is thus ∼100 kV/m2 per unit ĒBRAIN. CONCLUSIONS BBB stimulation by principle 1 suggests novel therapeutic strategies such as boosting metabolic capacity or interstitial fluid clearance. Whereas the spatial profile of EBRAIN is traditionally assumed to depend only on macroscopic anatomy, principle 2 suggests a central role for local capillary ultrastructure-which impact forms of neuromodulation including deep brain stimulation (DBS), spinal cord stimulation (SCS), transcranial magnetic stimulation (TMS), electroconvulsive therapy (ECT), and transcranial electrical stimulation (tES)/transcranial direct current stimulation (tDCS).
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Affiliation(s)
- Niranjan Khadka
- Department of Psychiatry, Laboratory for Neuropsychiatry and Neuromodulation, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
| | - Marom Bikson
- Department of Biomedical Engineering, The City College of New York, CUNY, New York, NY, USA.
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12
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Kreisberg E, Esmaeilpour Z, Adair D, Khadka N, Datta A, Badran BW, Bremner JD, Bikson M. High-resolution computational modeling of the current flow in the outer ear during transcutaneous auricular Vagus Nerve Stimulation (taVNS). Brain Stimul 2021; 14:1419-1430. [PMID: 34517143 PMCID: PMC8608747 DOI: 10.1016/j.brs.2021.09.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 09/07/2021] [Accepted: 09/09/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Transcutaneous auricular Vagus Nerve Stimulation (taVNS) applies low-intensity electrical current to the ear with the intention of activating the auricular branch of the Vagus nerve. The sensitivity and selectivity of stimulation applied to the ear depends on current flow pattern produced by a given electrode montage (size and placement). OBJECTIVE We compare different electrodes designs for taVNS considering both the predicted peak electric fields (sensitivity) and their spatial distribution (selectivity). METHODS Based on optimized high-resolution (0.47 mm) T1 and T2 weighted MRI, we developed an anatomical model of the left ear and the surrounding head tissues including brain, CSF/meninges, skull, muscle, blood vessels, fat, cartilage, and skin. The ear was further segmented into 6 regions of interest (ROI) based on various nerve densities: cavum concha, cymba concha, crus of helix, tragus, antitragus, and earlobe. A range of taVNS electrode montages were reproduced spanning varied electrodes sizes and placements over the tragus, cymba concha, earlobe, cavum concha, and crus of helix. Electric field across the ear (from superficial skin to cartilage) for each montage at 1 mA or 2 mA taVNS, assuming an activation threshold of 6.15 V/m, 12.3 V/m or 24.6 V/m was predicted using a Finite element method (FEM). Finally, considering every ROI, we calculated the sensitivity and selectivity of each montage. RESULTS Current flow patterns through the ear were highly specific to the electrode montage. Electric field was maximal at the ear regions directly under the electrodes, and for a given total current, increases with decreasing electrode size. Depending on the applied current and nerves threshold, activation may also occur in the regions between multiple anterior surface electrodes. Each considered montage was selective for one or two regions of interest. For example, electrodes across the tragus restricted significant electric field to the tragus. Stimulation across the earlobe restricted significant electric field to the earlobe and the antitragus. Because of this relative selectivity, use of control ear montages in experimental studies, support testing of targeting. Relative targeting was robust across assumptions of activation threshold and tissue properties. DISCUSSION Computational models provide additional insight on how details in electrode shape and placement impact sensitivity (how much current is needed) and selectivity (spatial distribution), thereby supporting analysis of existing approaches and optimization of new devices. Our result suggest taVNS current patterns and relative target are robust across individuals, though (variance in) axon morphology was not represented.
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Affiliation(s)
- Erica Kreisberg
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA
| | - Zeinab Esmaeilpour
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA
| | - Devin Adair
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA
| | - Niranjan Khadka
- Department of Psychiatry, Division of Neuropsychiatry and Neuromodulation, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Abhishek Datta
- Research and Development, Soterix Medical, New York, USA, The City College of the City University of New York, New York, USA
| | - Bashar W Badran
- Department of Psychiatry, Medical University of South Carolina, Charleston, SC, USA
| | - J Douglas Bremner
- Departments of Psychiatry & Behavioral Sciences and Radiology, Emory University School of Medicine, And the Atlanta VA Medical Center, Decatur, Atlanta, GA, USA
| | - Marom Bikson
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA.
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Focality-Oriented Selection of Current Dose for Transcranial Direct Current Stimulation. J Pers Med 2021; 11:jpm11090940. [PMID: 34575717 PMCID: PMC8466113 DOI: 10.3390/jpm11090940] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 09/18/2021] [Accepted: 09/18/2021] [Indexed: 11/30/2022] Open
Abstract
Background: In transcranial direct current stimulation (tDCS), the injected current becomes distributed across the brain areas. The objective is to stimulate the target region of interest (ROI) while minimizing the current in non-target ROIs (the 'focality' of tDCS). For this purpose, determining the appropriate current dose for an individual is difficult. Aim: To introduce a dose-target determination index (DTDI) to quantify the focality of tDCS and examine the dose-focality relationship in three different populations. Method: Here, we extended our previous toolbox i-SATA to the MNI reference space. After a tDCS montage is simulated for a current dose, the i-SATA(MNI) computes the average (over voxels) current density for every region in the brain. DTDI is the ratio of the average current density at the target ROI to the ROI with a maximum value (the peak region). Ideally, target ROI should be the peak region, so DTDI shall range from 0 to 1. The higher the value, the better the dose. We estimated the variation of DTDI within and across individuals using T1-weighted brain images of 45 males and females distributed equally across three age groups: (a) young adults (20 ≤ x ˂ 40 years), (b) mid adults (40 ≤ x ˂ 60 years), and (c) older adults (60 ≤ x ˂ 80 years). DTDI's were evaluated for the frontal montage with electrodes at F3 and the right supraorbital for three current doses of 1 mA, 2 mA, and 3 mA, with the target ROI at the left middle frontal gyrus. Result: As the dose is incremented, DTDI may show (a) increase, (b) decrease, and (c) no change across the individuals depending on the relationship (nonlinear or linear) between the injected tDCS current and the distribution of current density in the target ROI. The nonlinearity is predominant in older adults with a decrease in focality. The decline is stronger in males. Higher current dose at older age can enhance the focality of stimulation. Conclusion: DTDI provides information on which tDCS current dose will optimize the focality of stimulation. The recommended DTDI dose should be prioritized based on the age (>40 years) and sex (especially for males) of an individual. The toolbox i-SATA(MNI) is freely available.
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14
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Unal G, Swami JK, Canela C, Cohen SL, Khadka N, FallahRad M, Short B, Argyelan M, Sackeim HA, Bikson M. Adaptive current-flow models of ECT: Explaining individual static impedance, dynamic impedance, and brain current density. Brain Stimul 2021; 14:1154-1168. [PMID: 34332156 DOI: 10.1016/j.brs.2021.07.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 07/19/2021] [Accepted: 07/22/2021] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Improvements in electroconvulsive therapy (ECT) outcomes have followed refinement in device electrical output and electrode montage. The physical properties of the ECT stimulus, together with those of the patient's head, determine the impedances measured by the device and govern current delivery to the brain and ECT outcomes. OBJECTIVE However, the precise relations among physical properties of the stimulus, patient head anatomy, and patient-specific impedance to the passage of current are long-standing questions in ECT research and practice. To this end, we develop a computational framework based on diverse clinical data sets. METHODS We developed anatomical MRI-derived models of transcranial electrical stimulation (tES) that included changes in tissue conductivity due to local electrical current flow. These "adaptive" models simulate ECT both during therapeutic stimulation using high current (∼1 A) and when dynamic impedance is measured, as well as prior to stimulation when low current (∼1 mA) is used to measure static impedance. We modeled two scalp layers: a superficial scalp layer with adaptive conductivity that increases with electric field up to a subject-specific maximum (σSS¯), and a deep scalp layer with a subject-specific fixed conductivity (σDS). RESULTS We demonstrated that variation in these scalp parameters may explain clinical data on subject-specific static impedance and dynamic impedance, their imperfect correlation across subjects, their relationships to seizure threshold, and the role of head anatomy. Adaptive tES models demonstrated that current flow changes local tissue conductivity which in turn shapes current delivery to the brain in a manner not accounted for in fixed tissue conductivity models. CONCLUSIONS Our predictions that variation in individual skin properties, rather than other aspects of anatomy, largely govern the relationship between static impedance, dynamic impedance, and ECT current delivery to the brain, themselves depend on assumptions about tissue properties. Broadly, our novel modeling pipeline opens the door to explore how adaptive-scalp conductivity may impact transcutaneous electrical stimulation (tES).
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Affiliation(s)
- Gozde Unal
- Department of Biomedical Engineering, The City College of New York, CUNY, New York, NY, USA.
| | - Jaiti K Swami
- Department of Biomedical Engineering, The City College of New York, CUNY, New York, NY, USA
| | - Carliza Canela
- Department of Biomedical Engineering, The City College of New York, CUNY, New York, NY, USA
| | - Samantha L Cohen
- Department of Biomedical Engineering, Cornell University, Ithaca, NY, 14850, USA
| | - Niranjan Khadka
- Department of Psychiatry, Laboratory for Neuropsychiatry and Neuromodulation, Massachusetts General Hospital, Harvard Medical School, MA, USA
| | - Mohamad FallahRad
- Department of Biomedical Engineering, The City College of New York, CUNY, New York, NY, USA
| | - Baron Short
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, USA
| | - Miklos Argyelan
- Center for Neurosciences, The Feinstein Institute for Medical Research, North Shore- Long Island Jewish Health System, Manhasset, NY, 11030, USA
| | - Harold A Sackeim
- Department of Psychiatry and Radiology, Vagelos College of Physicians and Surgeons, Columbia University, New York, USA
| | - Marom Bikson
- Department of Biomedical Engineering, The City College of New York, CUNY, New York, NY, USA.
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15
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Limited Sensitivity of Hippocampal Synaptic Function or Network Oscillations to Unmodulated Kilohertz Electric Fields. eNeuro 2020; 7:ENEURO.0368-20.2020. [PMID: 33328248 PMCID: PMC7773889 DOI: 10.1523/eneuro.0368-20.2020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 11/03/2020] [Accepted: 11/05/2020] [Indexed: 11/21/2022] Open
Abstract
Understanding the cellular mechanisms of kilohertz (kHz) electrical stimulation is of broad interest in neuromodulation including forms of transcranial electrical stimulation, interferential stimulation, and high-rate spinal cord stimulation (SCS). Yet, the well-established low-pass filtering by neuronal membranes suggests minimal neuronal polarization in respond to charge-balanced kHz stimulation. The hippocampal brain slice model is among the most studied systems in neuroscience and exhaustively characterized in screening the effects of electrical stimulation. High-frequency electric fields of varied amplitudes (1–150 V/m), waveforms (sinusoidal, symmetrical pule, asymmetrical pulse) and frequencies (1 and10 kHz) were tested. Changes in single or paired-pulse field EPSPs (fEPSP) in CA1 were measured in response to radial-directed and tangential-directed electric fields, with brief (30 s) or long (30 min) application times. The effects of kHz stimulation on ongoing endogenous network activity were tested in carbachol-induced γ oscillation of CA3a and CA3c. Across 23 conditions evaluated, no significant changes in fEPSP were resolved, while responses were detected for within-slice control direct current (DC) fields; 1-kHz sinusoidal and pulse stimulation (≥60 V/m), but not 10 kHz, induced changes in oscillating neuronal network. We thus report no responses to low-amplitude 1-kHz or any 10-kHz fields, suggesting that any brain sensitivity to these fields is via yet to be-determined mechanism(s) of action which were not identified in our experimental preparation.
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16
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Esmaeilpour Z, Kronberg G, Reato D, Parra LC, Bikson M. Temporal interference stimulation targets deep brain regions by modulating neural oscillations. Brain Stimul 2020; 14:55-65. [PMID: 33186778 PMCID: PMC9382891 DOI: 10.1016/j.brs.2020.11.007] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 11/06/2020] [Accepted: 11/07/2020] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Temporal interference (TI) stimulation of the brain generates amplitude-modulated electric fields oscillating in the kHz range with the goal of non-invasive targeted deep brain stimulation. Yet, the current intensities required in human (sensitivity) to modulate deep brain activity and if superficial brain region are spared (selectivity) at these intensities remains unclear. OBJECTIVE We developed an experimentally constrained theory for TI sensitivity to kHz electric field given the attenuation by membrane low-pass filtering property, and for TI selectivity to deep structures given the distribution of modulated and unmodulated electric fields in brain. METHODS The electric field threshold to modulate carbachol-induced gamma oscillations in rat hippocampal slices was determined for unmodulated 0.05-2 kHz sine waveforms, and 5 Hz amplitude-modulated waveforms with 0.1-2 kHz carrier frequencies. The neuronal effects are replicated with a computational network model to explore the underlying mechanisms, and then coupled to a validated current-flow model of the human head. RESULTS Amplitude-modulated electric fields are stronger in deep brain regions, while unmodulated electric fields are maximal at the cortical regions. Both experiment and model confirmed the hypothesis that spatial selectivity of temporal interference stimulation depends on the phasic modulation of neural oscillations only in deep brain regions. Adaptation mechanism (e.g. GABAb) enhanced sensitivity to amplitude modulated waveform in contrast to unmodulated kHz and produced selectivity in modulating gamma oscillation (i.e. Higher gamma modulation in amplitude modulated vs unmodulated kHz stimulation). Selection of carrier frequency strongly affected sensitivity to amplitude modulation stimulation. Amplitude modulated stimulation with 100 Hz carrier frequency required ∼5 V/m (corresponding to ∼13 mA at the scalp surface), whereas, 1 kHz carrier frequency ∼60 V/m (∼160 mA) and 2 kHz carrier frequency ∼80 V/m (∼220 mA) to significantly modulate gamma oscillation. Sensitivity is increased (scalp current required decreased) for theoretical neuronal membranes with faster time constants. CONCLUSION The TI sensitivity (current required at the scalp) depends on the neuronal membrane time-constant (e.g. axons) approaching the kHz carrier frequency. TI selectivity is governed by network adaption (e.g. GABAb) that is faster than the amplitude-modulation frequency. Thus, we show neuronal and network oscillations time-constants determine the scalp current required and the selectivity achievable with TI in humans.
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Affiliation(s)
- Zeinab Esmaeilpour
- Department of Biomedical Engineering, The City College of the City University of New York, New York, NY, USA.
| | - Greg Kronberg
- Department of Biomedical Engineering, The City College of the City University of New York, New York, NY, USA
| | - Davide Reato
- Champalimaud Centre for the Unknown, Neuroscience Program, Lisbon, Portugal
| | - Lucas C Parra
- Department of Biomedical Engineering, The City College of the City University of New York, New York, NY, USA
| | - Marom Bikson
- Department of Biomedical Engineering, The City College of the City University of New York, New York, NY, USA
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17
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Albizu A, Fang R, Indahlastari A, O'Shea A, Stolte SE, See KB, Boutzoukas EM, Kraft JN, Nissim NR, Woods AJ. Machine learning and individual variability in electric field characteristics predict tDCS treatment response. Brain Stimul 2020; 13:1753-1764. [PMID: 33049412 PMCID: PMC7731513 DOI: 10.1016/j.brs.2020.10.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 09/30/2020] [Accepted: 10/02/2020] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Transcranial direct current stimulation (tDCS) is widely investigated as a therapeutic tool to enhance cognitive function in older adults with and without neurodegenerative disease. Prior research demonstrates that electric current delivery to the brain can vary significantly across individuals. Quantification of this variability could enable person-specific optimization of tDCS outcomes. This pilot study used machine learning and MRI-derived electric field models to predict working memory improvements as a proof of concept for precision cognitive intervention. METHODS Fourteen healthy older adults received 20 minutes of 2 mA tDCS stimulation (F3/F4) during a two-week cognitive training intervention. Participants performed an N-back working memory task pre-/post-intervention. MRI-derived current models were passed through a linear Support Vector Machine (SVM) learning algorithm to characterize crucial tDCS current components (intensity and direction) that induced working memory improvements in tDCS responders versus non-responders. MAIN RESULTS SVM models of tDCS current components had 86% overall accuracy in classifying treatment responders vs. non-responders, with current intensity producing the best overall model differentiating changes in working memory performance. Median current intensity and direction in brain regions near the electrodes were positively related to intervention responses (r=0.811,p<0.001 and r=0.774,p=0.001). CONCLUSIONS This study provides the first evidence that pattern recognition analyses of MRI-derived tDCS current models can provide individual prognostic classification of tDCS treatment response with 86% accuracy. Individual differences in current intensity and direction play important roles in determining treatment response to tDCS. These findings provide important insights into mechanisms of tDCS response as well as proof of concept for future precision dosing models of tDCS intervention.
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Affiliation(s)
- Alejandro Albizu
- Center for Cognitive Aging and Memory, McKnight Brain Institute, University of Florida, Gainesville, USA; Department of Neuroscience, College of Medicine, University of Florida, Gainesville, USA
| | - Ruogu Fang
- Center for Cognitive Aging and Memory, McKnight Brain Institute, University of Florida, Gainesville, USA; J. Crayton Pruitt Family Department of Biomedical Engineering, Herbert Wertheim College of Engineering, University of Florida, Gainesville, USA
| | - Aprinda Indahlastari
- Center for Cognitive Aging and Memory, McKnight Brain Institute, University of Florida, Gainesville, USA; Department of Clinical and Health Psychology, College of Public Health and Health Professions, University of Florida, Gainesville, USA
| | - Andrew O'Shea
- Center for Cognitive Aging and Memory, McKnight Brain Institute, University of Florida, Gainesville, USA; Department of Clinical and Health Psychology, College of Public Health and Health Professions, University of Florida, Gainesville, USA
| | - Skylar E Stolte
- J. Crayton Pruitt Family Department of Biomedical Engineering, Herbert Wertheim College of Engineering, University of Florida, Gainesville, USA
| | - Kyle B See
- J. Crayton Pruitt Family Department of Biomedical Engineering, Herbert Wertheim College of Engineering, University of Florida, Gainesville, USA
| | - Emanuel M Boutzoukas
- Center for Cognitive Aging and Memory, McKnight Brain Institute, University of Florida, Gainesville, USA; Department of Clinical and Health Psychology, College of Public Health and Health Professions, University of Florida, Gainesville, USA
| | - Jessica N Kraft
- Center for Cognitive Aging and Memory, McKnight Brain Institute, University of Florida, Gainesville, USA; Department of Neuroscience, College of Medicine, University of Florida, Gainesville, USA
| | - Nicole R Nissim
- Center for Cognitive Aging and Memory, McKnight Brain Institute, University of Florida, Gainesville, USA; Department of Neuroscience, College of Medicine, University of Florida, Gainesville, USA
| | - Adam J Woods
- Center for Cognitive Aging and Memory, McKnight Brain Institute, University of Florida, Gainesville, USA; Department of Neuroscience, College of Medicine, University of Florida, Gainesville, USA; Department of Clinical and Health Psychology, College of Public Health and Health Professions, University of Florida, Gainesville, USA.
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18
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Unal G, Ficek B, Webster K, Shahabuddin S, Truong D, Hampstead B, Bikson M, Tsapkini K. Impact of brain atrophy on tDCS and HD-tDCS current flow: a modeling study in three variants of primary progressive aphasia. Neurol Sci 2020; 41:1781-1789. [PMID: 32040791 PMCID: PMC7363529 DOI: 10.1007/s10072-019-04229-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2019] [Accepted: 12/24/2019] [Indexed: 12/12/2022]
Abstract
BACKGROUND During transcranial direct current stimulation (tDCS), the amount and distribution of current that reaches the brain depends on individual anatomy. Many progressive neurodegenerative diseases are associated with cortical atrophy, but the importance of individual brain atrophy during tDCS in patients with progressive atrophy, including primary progressive aphasia (PPA), remains unclear. OBJECTIVE In the present study, we addressed the question whether brain anatomy in patients with distinct cortical atrophy patterns would impact brain current intensity and distribution during tDCS over the left IFG. METHOD We developed state-of-the-art, gyri-precise models of three subjects, each representing a variant of primary progressive aphasia: non-fluent variant PPA (nfvPPA), semantic variant PPA (svPPA), and logopenic variant PPA (lvPPA). We considered two exemplary montages over the left inferior frontal gyrus (IFG): a conventional pad montage (anode over F7, cathode over the right cheek) and a 4 × 1 high-definition tDCS montage. We further considered whether local anatomical features, specifically distance of the cortex to skull, can directly predict local electric field intensity. RESULTS We found that the differences in brain current flow across the three PPA variants fall within the distribution of anatomically typical adults. While clustering of electric fields was often around individual gyri or sulci, the minimal distance from the gyri/sulci to skull was not correlated with electric field intensity. CONCLUSION Limited to the conditions and assumptions considered here, this argues against a specific need to adjust the tDCS montage for these patients any more than might be considered useful in anatomically typical adults. Therefore, local atrophy does not, in isolation, reliably predict local electric field. Rather, our results are consistent with holistic head anatomy influencing brain current flow, with tDCS producing diffuse and individualized brain current flow patterns and HD-tDCS producing targeted brain current flow across individuals.
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Affiliation(s)
- Gozde Unal
- Department of Biomedical Engineering, The City College of New York, New York, NY, 10031, USA
| | - Bronte Ficek
- Department of Neurology, Cerebrovascular Division, Johns Hopkins Medicine, 600 N. Wolfe Street, Phipps 488, Baltimore, MD, 21287, USA
| | - Kimberly Webster
- Department of Neurology, Cerebrovascular Division, Johns Hopkins Medicine, 600 N. Wolfe Street, Phipps 488, Baltimore, MD, 21287, USA
- Department of Otolaryngology, Johns Hopkins Medicine, Baltimore, MD, 21287, USA
| | - Syed Shahabuddin
- Department of Biomedical Engineering, The City College of New York, New York, NY, 10031, USA
| | - Dennis Truong
- Department of Biomedical Engineering, The City College of New York, New York, NY, 10031, USA
| | - Benjamin Hampstead
- Department of Psychiatry, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Marom Bikson
- Department of Biomedical Engineering, The City College of New York, New York, NY, 10031, USA
| | - Kyrana Tsapkini
- Department of Neurology, Cerebrovascular Division, Johns Hopkins Medicine, 600 N. Wolfe Street, Phipps 488, Baltimore, MD, 21287, USA.
- Department of Cognitive Science, Johns Hopkins Medicine, Baltimore, MD, 21218, USA.
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A flexible workflow for simulating transcranial electric stimulation in healthy and lesioned brains. PLoS One 2020; 15:e0228119. [PMID: 32407389 PMCID: PMC7224502 DOI: 10.1371/journal.pone.0228119] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 04/23/2020] [Indexed: 01/22/2023] Open
Abstract
Simulating transcranial electric stimulation is actively researched as knowledge about the distribution of the electrical field is decisive for understanding the variability in the elicited stimulation effect. Several software pipelines comprehensively solve this task in an automated manner for standard use-cases. However, simulations for non-standard applications such as uncommon electrode shapes or the creation of head models from non-optimized T1-weighted imaging data and the inclusion of irregular structures are more difficult to accomplish. We address these limitations and suggest a comprehensive workflow to simulate transcranial electric stimulation based on open-source tools. The workflow covers the head model creation from MRI data, the electrode modeling, the modeling of anisotropic conductivity behavior of the white matter, the numerical simulation and visualization. Skin, skull, air cavities, cerebrospinal fluid, white matter, and gray matter are segmented semi-automatically from T1-weighted MR images. Electrodes of arbitrary number and shape can be modeled. The meshing of the head model is implemented in a way to preserve the feature edges of the electrodes and is free of topological restrictions of the considered structures of the head model. White matter anisotropy can be computed from diffusion-tensor imaging data. Our solver application was verified analytically and by contrasting the tDCS simulation results with that of other simulation pipelines (SimNIBS 3.0, ROAST 3.0). An agreement in both cases underlines the validity of our workflow. Our suggested solutions facilitate investigations of irregular structures in patients (e.g. lesions, implants) or new electrode types. For a coupled use of the described workflow, we provide documentation and disclose the full source code of the developed tools.
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20
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Esmaeilpour Z, Shereen AD, Ghobadi‐Azbari P, Datta A, Woods AJ, Ironside M, O'Shea J, Kirk U, Bikson M, Ekhtiari H. Methodology for tDCS integration with fMRI. Hum Brain Mapp 2020; 41:1950-1967. [PMID: 31872943 PMCID: PMC7267907 DOI: 10.1002/hbm.24908] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 11/09/2019] [Accepted: 12/10/2019] [Indexed: 12/28/2022] Open
Abstract
Understanding and reducing variability of response to transcranial direct current stimulation (tDCS) requires measuring what factors predetermine sensitivity to tDCS and tracking individual response to tDCS. Human trials, animal models, and computational models suggest structural traits and functional states of neural systems are the major sources of this variance. There are 118 published tDCS studies (up to October 1, 2018) that used fMRI as a proxy measure of neural activation to answer mechanistic, predictive, and localization questions about how brain activity is modulated by tDCS. FMRI can potentially contribute as: a measure of cognitive state-level variance in baseline brain activation before tDCS; inform the design of stimulation montages that aim to target functional networks during specific tasks; and act as an outcome measure of functional response to tDCS. In this systematic review, we explore methodological parameter space of tDCS integration with fMRI spanning: (a) fMRI timing relative to tDCS (pre, post, concurrent); (b) study design (parallel, crossover); (c) control condition (sham, active control); (d) number of tDCS sessions; (e) number of follow up scans; (f) stimulation dose and combination with task; (g) functional imaging sequence (BOLD, ASL, resting); and (h) additional behavioral (cognitive, clinical) or quantitative (neurophysiological, biomarker) measurements. Existing tDCS-fMRI literature shows little replication across these permutations; few studies used comparable study designs. Here, we use a representative sample study with both task and resting state fMRI before and after tDCS in a crossover design to discuss methodological confounds. We further outline how computational models of current flow should be combined with imaging data to understand sources of variability. Through the representative sample study, we demonstrate how modeling and imaging methodology can be integrated for individualized analysis. Finally, we discuss the importance of conducting tDCS-fMRI with stimulation equipment certified as safe to use inside the MR scanner, and of correcting for image artifacts caused by tDCS. tDCS-fMRI can address important questions on the functional mechanisms of tDCS action (e.g., target engagement) and has the potential to support enhancement of behavioral interventions, provided studies are designed rationally.
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Affiliation(s)
- Zeinab Esmaeilpour
- Neural Engineering Laboratory, Department of Biomedical EngineeringThe City College of the City University of New York, City College Center for Discovery and InnovationNew YorkNew York
| | - A. Duke Shereen
- Advanced Science Research Center, The Graduate CenterCity University of New YorkNew YorkNew York
| | | | | | - Adam J. Woods
- Center for Cognitive Aging and Memory, McKnight Brain Institute, Department of Clinical and Health PsychologyUniversity of FloridaGainesvilleFlorida
| | - Maria Ironside
- Center for Depression, Anxiety and Stress Research, McLean HospitalBelmontMassachusetts
- Department of PsychiatryHarvard Medical SchoolBostonMassachusetts
| | - Jacinta O'Shea
- Nuffield Department of Clinical Neuroscience, Medical Science DivisionUniversity of OxfordOxfordEnglandUK
| | - Ulrich Kirk
- Department of PsychologyUniversity of Southern DenmarkOdenseDenmark
| | - Marom Bikson
- Neural Engineering Laboratory, Department of Biomedical EngineeringThe City College of the City University of New York, City College Center for Discovery and InnovationNew YorkNew York
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21
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Prevention of schizophrenia deficits via non-invasive adolescent frontal cortex stimulation in rats. Mol Psychiatry 2020; 25:896-905. [PMID: 30692610 DOI: 10.1038/s41380-019-0356-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 11/28/2018] [Accepted: 12/20/2018] [Indexed: 12/17/2022]
Abstract
Schizophrenia is a severe neurodevelopmental psychiatric affliction manifested behaviorally at late adolescence/early adulthood. Current treatments comprise antipsychotics which act solely symptomatic, are limited in their effectiveness and often associated with side-effects. We here report that application of non-invasive transcranial direct current stimulation (tDCS) during adolescence, prior to schizophrenia-relevant behavioral manifestation, prevents the development of positive symptoms and related neurobiological alterations in the maternal immune stimulation (MIS) model of schizophrenia.
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22
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Khadka N, Truong DQ, Williams P, Martin JH, Bikson M. The Quasi-uniform assumption for Spinal Cord Stimulation translational research. J Neurosci Methods 2019; 328:108446. [PMID: 31589892 DOI: 10.1016/j.jneumeth.2019.108446] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 09/23/2019] [Accepted: 09/25/2019] [Indexed: 12/18/2022]
Abstract
BACKGROUND Quasi-uniform assumption is a general theory that postulates local electric field predicts neuronal activation. Computational current flow model of spinal cord stimulation (SCS) of humans and animal models inform how the quasi-uniform assumption can support scaling neuromodulation dose between humans and translational animal. NEW METHOD Here we developed finite element models of cat and rat SCS, and brain slice, alongside SCS models. Boundary conditions related to species specific electrode dimensions applied, and electric fields per unit current (mA) predicted. RESULTS Clinically and across animal, electric fields change abruptly over small distance compared to the neuronal morphology, such that each neuron is exposed to multiple electric fields. Per unit current, electric fields generally decrease with body mass, but not necessarily and proportionally across tissues. Peak electric field in dorsal column rat and cat were ∼17x and ∼1x of clinical values, for scaled electrodes and equal current. Within the spinal cord, the electric field for rat, cat, and human decreased to 50% of peak value caudo-rostrally (C5-C6) at 0.48 mm, 3.2 mm, and 8 mm, and mediolaterally at 0.14 mm, 2.3 mm, and 3.1 mm. Because these space constants are different, electric field across species cannot be matched without selecting a region of interest (ROI). COMPARISON WITH EXISTING METHOD This is the first computational model to support scaling neuromodulation dose between humans and translational animal. CONCLUSIONS Inter-species reproduction of the electric field profile across the entire surface of neuron populations is intractable. Approximating quasi-uniform electric field in a ROI is a rational step to translational scaling.
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Affiliation(s)
- Niranjan Khadka
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA.
| | - Dennis Q Truong
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA
| | - Preston Williams
- Department of Molecular, Cellular, and Biomedical Sciences, City University of NY School of Medicine, New York, NY, 10031, USA
| | - John H Martin
- CUNY Graduate Center, New York, NY, 10031, USA; Department of Molecular, Cellular, and Biomedical Sciences, City University of NY School of Medicine, New York, NY, 10031, USA
| | - Marom Bikson
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA.
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23
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Yang Q, Ramamurthy A, Lall S, Santos J, Ratnadurai-Giridharan S, Lopane M, Zareen N, Alexander H, Ryan D, Martin JH, Carmel JB. Independent replication of motor cortex and cervical spinal cord electrical stimulation to promote forelimb motor function after spinal cord injury in rats. Exp Neurol 2019; 320:112962. [PMID: 31125548 PMCID: PMC7035596 DOI: 10.1016/j.expneurol.2019.112962] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 05/16/2019] [Accepted: 05/19/2019] [Indexed: 12/24/2022]
Abstract
Cervical spinal cord injury (SCI) impairs arm and hand function largely by interrupting descending tracts. Most SCI spare some axons at the lesion, including the corticospinal tract (CST), which is critical for voluntary movement. We targeted descending motor connections with paired electrical stimulation of motor cortex and cervical spinal cord in the rat. We sought to replicate the previously published effects of intermittent theta burst stimulation of forelimb motor cortex combined with trans-spinal direct current stimulation placed on the skin over the neck to target the cervical enlargement. We hypothesized that paired stimulation would improve performance in skilled walking and food manipulation (IBB) tasks. Rats received a moderate C4 spinal cord contusion injury (200 kDynes), which ablates the main CST. They were randomized to receive paired stimulation for 10 consecutive days starting 11 days after injury, or no stimulation. Behavior was assessed weekly from weeks 4-7 after injury, and then CST axons were traced. Rats with paired cortical and spinal stimulation achieved significantly better forelimb motor function recovery, as measured by fewer stepping errors on the horizontal ladder task (34 ± 9% in stimulation group vs. 51 ± 18% in control, p = .013) and higher scores on the food manipulation task (IBB, 0-9 score; 7.2 ± 0.8 in stimulated rats vs. 5.2 ± 2.6 in controls, p = .025). The effect size for both tasks was large (Cohen's d = 1.0 and 0.92, respectively). The CST axon length in the cervical spinal cord did not differ significantly between the groups, but there was denser and broader ipsilateral axons distribution distal to the spinal cord injury. The large behavioral effect and replication in an independent laboratory validate this approach, which will be trialed in cats before being tested in people using non-invasive methods.
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Affiliation(s)
- Qi Yang
- Departments of Neurology and Orthopedics, Columbia University, New York, NY 10031, USA
| | - Aditya Ramamurthy
- Departments of Neurology and Orthopedics, Columbia University, New York, NY 10031, USA
| | - Sophia Lall
- Burke Neurological Institute, Weill Cornell Medicine, White Plains, NY 10605, USA
| | - Joshua Santos
- Burke Neurological Institute, Weill Cornell Medicine, White Plains, NY 10605, USA
| | | | - Madeleine Lopane
- Burke Neurological Institute, Weill Cornell Medicine, White Plains, NY 10605, USA
| | - Neela Zareen
- Department of Molecular, Cellular, and Biomedical Sciences, City University of NY School of Medicine, New York, NY 10031, USA
| | - Heather Alexander
- Department of Molecular, Cellular, and Biomedical Sciences, City University of NY School of Medicine, New York, NY 10031, USA
| | - Daniel Ryan
- Department of Molecular, Cellular, and Biomedical Sciences, City University of NY School of Medicine, New York, NY 10031, USA
| | - John H Martin
- Department of Molecular, Cellular, and Biomedical Sciences, City University of NY School of Medicine, New York, NY 10031, USA; CUNY Graduate Center, New York, NY 10031, USA
| | - Jason B Carmel
- Departments of Neurology and Orthopedics, Columbia University, New York, NY 10031, USA.
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24
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Lattari E, Vieira LAF, Oliveira BRR, Unal G, Bikson M, de Mello Pedreiro RC, Marques Neto SR, Machado S, Maranhão-Neto GA. Effects of Transcranial Direct Current Stimulation With Caffeine Intake on Muscular Strength and Perceived Exertion. J Strength Cond Res 2019; 33:1237-1243. [PMID: 30908367 DOI: 10.1519/jsc.0000000000003123] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Lattari, E, Vieira, LAF, Oliveira, BRR, Unal, G, Bikson, M, de Mello Pedreiro, RC, Marques Neto, SR, Machado, S, and Maranhão-Neto, GA. Effects of transcranial direct current stimulation with caffeine intake on muscular strength and perceived exertion. J Strength Cond Res 33(5): 1237-1243, 2019-The aim of this study was to investigate the acute effects of transcranial direct current stimulation (tDCS) associated with caffeine intake on muscular strength and ratings of perceived exertion (RPE). Fifteen healthy young males recreationally trained (age: 25.3 ± 3.2 years, body mass: 78.0 ± 6.9 kg, height: 174.1 ± 6.1 cm) were recruited. The experimental conditions started with the administration of caffeine (Caff) or placebo (Pla) 1 hour before starting the anodal tDCS (a-tDCS or sham). There was an intake of 5 mg·kg of Caff or 5 mg·kg of Pla. After the intake, a-tDCS or sham was applied in the left dorsolateral prefrontal cortex with intensity of 2 mA and 20 minutes of duration. The experimental conditions were defined as Sham + Pla, a-tDCS + Pla, Sham + Caff, and a-tDCS + Caff. After the conditions, muscular strength and RPE were verified. Muscular strength was determined by volume load performed in bench press exercise. Muscular strength in Sham + Pla condition was lower compared with all others conditions (p < 0.05). The RPE in the Sham + Pla was greater compared with a-tDCS + Caff (p < 0.05). Muscular strength was greater in all experimental conditions, and a-tDCS + Caff had lower RPE compared with placebo. When very little gains in muscle strength are expected, both caffeine and tDCS were effective in increasing muscle strength. Besides, the improvement in RPE of the caffeine associated with a-tDCS could prove advantageous in participants experienced in strength training. In fact, coaches and applied sport scientists quantitating the intensity of training based on RPE.
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Affiliation(s)
- Eduardo Lattari
- Physical Activity Neuroscience Laboratory (LABNAF), Physical Activity Sciences Postgraduate Program, Salgado de Oliveira University (UNIVERSO), Niterói, Brazil
| | - Lucas A F Vieira
- Physical Activity Sciences Laboratory (LACAF), Physical Activity Sciences Postgraduate Program, Salgado de Oliveira University (UNIVERSO), Niterói, Brazil
| | - Bruno R R Oliveira
- Department of Physical Education, Brazilian Institute of Medicine of Rehabilitation, Rio de Janeiro, RJ, Brazil
| | - Gözde Unal
- Department of Biomedical Engineering, The City College of New York of CUNY, New York, New York
| | - Marom Bikson
- Department of Biomedical Engineering, The City College of New York of CUNY, New York, New York
| | - Rodrigo C de Mello Pedreiro
- Physical Activity Sciences Laboratory (LACAF), Physical Activity Sciences Postgraduate Program, Salgado de Oliveira University (UNIVERSO), Niterói, Brazil
| | - Silvio R Marques Neto
- Physical Activity Sciences Laboratory (LACAF), Physical Activity Sciences Postgraduate Program, Salgado de Oliveira University (UNIVERSO), Niterói, Brazil
| | - Sérgio Machado
- Physical Activity Neuroscience Laboratory (LABNAF), Physical Activity Sciences Postgraduate Program, Salgado de Oliveira University (UNIVERSO), Niterói, Brazil
| | - Geraldo A Maranhão-Neto
- Physical Activity Sciences Laboratory (LACAF), Physical Activity Sciences Postgraduate Program, Salgado de Oliveira University (UNIVERSO), Niterói, Brazil
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25
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Valero-Cabré A, Sanches C, Godard J, Fracchia O, Dubois B, Levy R, Truong DQ, Bikson M, Teichmann M. Language boosting by transcranial stimulation in progressive supranuclear palsy. Neurology 2019; 93:e537-e547. [PMID: 31270217 DOI: 10.1212/wnl.0000000000007893] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 03/22/2019] [Indexed: 12/29/2022] Open
Abstract
OBJECTIVE To explore whether transcranial direct current stimulation (tDCS) over the dorsolateral prefrontal cortex (DLPFC) can improve language capacities in patients with progressive supranuclear palsy (PSP). METHODS We used a sham-controlled double-blind crossover design to assess the efficiency of tDCS over the DLPFC in a cohort of 12 patients with PSP. In 3 separate sessions, we evaluated the ability to boost the left DLPFC via left-anodal (excitatory) and right-cathodal (inhibitory) tDCS, while comparing them to sham tDCS. Tasks assessing lexical access (letter fluency task) and semantic access (category judgment task) were applied immediately before and after the tDCS sessions to provide a marker of potential language modulation. RESULTS The comparison with healthy controls showed that patients with PSP were impaired on both tasks at baseline. Contrasting poststimulation vs prestimulation performance across tDCS conditions revealed language improvement in the category judgment task following right-cathodal tDCS, and in the letter fluency task following left-anodal tDCS. A computational finite element model of current distribution corroborated the intended effect of left-anodal and right-cathodal tDCS on the targeted DLPFC. CONCLUSIONS Our results demonstrate tDCS-driven language improvement in PSP. They provide proof-of-concept for the use of tDCS in PSP and set the stage for future multiday stimulation regimens, which might lead to longer-lasting therapeutic effects promoted by neuroplasticity. CLASSIFICATION OF EVIDENCE This study provides Class III evidence that for patients with PSP, tDCS over the DLPFC improves performance in some language tasks.
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Affiliation(s)
- Antoni Valero-Cabré
- From Groupe de Dynamiques Cérébrales, Plasticité et Rééducation (A.V.-C., C.S., J.G., O.F.) and Frontlab Team (A.V.-C., C.S., J.G., O.F., B.D., R.L., M.T.), Institut du Cerveau et de la Moelle Epinière (ICM), INSERM 1127, CNRS, UMR 7225 and Sorbonne Université (SO), Paris, France; Laboratory for Cerebral Dynamics Plasticity and Rehabilitation (A.V.-C.), Boston University School of Medicine, MA; Cognitive Neuroscience and Information Technology Research Program (A.V.-C.), Open University of Catalonia (UOC), Barcelona, Spain; Department of Neurology (B.D., R.L., M.T.), National Reference Center for "PPA and Rare Dementias," Pitié Salpêtrière Hospital, AP-HP, Paris, France; and Neural Engineering Laboratory, Department of Biomedical Engineering (D.Q.T., M.B.), the City College of City University of New York, NY.
| | - Clara Sanches
- From Groupe de Dynamiques Cérébrales, Plasticité et Rééducation (A.V.-C., C.S., J.G., O.F.) and Frontlab Team (A.V.-C., C.S., J.G., O.F., B.D., R.L., M.T.), Institut du Cerveau et de la Moelle Epinière (ICM), INSERM 1127, CNRS, UMR 7225 and Sorbonne Université (SO), Paris, France; Laboratory for Cerebral Dynamics Plasticity and Rehabilitation (A.V.-C.), Boston University School of Medicine, MA; Cognitive Neuroscience and Information Technology Research Program (A.V.-C.), Open University of Catalonia (UOC), Barcelona, Spain; Department of Neurology (B.D., R.L., M.T.), National Reference Center for "PPA and Rare Dementias," Pitié Salpêtrière Hospital, AP-HP, Paris, France; and Neural Engineering Laboratory, Department of Biomedical Engineering (D.Q.T., M.B.), the City College of City University of New York, NY
| | - Juliette Godard
- From Groupe de Dynamiques Cérébrales, Plasticité et Rééducation (A.V.-C., C.S., J.G., O.F.) and Frontlab Team (A.V.-C., C.S., J.G., O.F., B.D., R.L., M.T.), Institut du Cerveau et de la Moelle Epinière (ICM), INSERM 1127, CNRS, UMR 7225 and Sorbonne Université (SO), Paris, France; Laboratory for Cerebral Dynamics Plasticity and Rehabilitation (A.V.-C.), Boston University School of Medicine, MA; Cognitive Neuroscience and Information Technology Research Program (A.V.-C.), Open University of Catalonia (UOC), Barcelona, Spain; Department of Neurology (B.D., R.L., M.T.), National Reference Center for "PPA and Rare Dementias," Pitié Salpêtrière Hospital, AP-HP, Paris, France; and Neural Engineering Laboratory, Department of Biomedical Engineering (D.Q.T., M.B.), the City College of City University of New York, NY
| | - Oriane Fracchia
- From Groupe de Dynamiques Cérébrales, Plasticité et Rééducation (A.V.-C., C.S., J.G., O.F.) and Frontlab Team (A.V.-C., C.S., J.G., O.F., B.D., R.L., M.T.), Institut du Cerveau et de la Moelle Epinière (ICM), INSERM 1127, CNRS, UMR 7225 and Sorbonne Université (SO), Paris, France; Laboratory for Cerebral Dynamics Plasticity and Rehabilitation (A.V.-C.), Boston University School of Medicine, MA; Cognitive Neuroscience and Information Technology Research Program (A.V.-C.), Open University of Catalonia (UOC), Barcelona, Spain; Department of Neurology (B.D., R.L., M.T.), National Reference Center for "PPA and Rare Dementias," Pitié Salpêtrière Hospital, AP-HP, Paris, France; and Neural Engineering Laboratory, Department of Biomedical Engineering (D.Q.T., M.B.), the City College of City University of New York, NY
| | - Bruno Dubois
- From Groupe de Dynamiques Cérébrales, Plasticité et Rééducation (A.V.-C., C.S., J.G., O.F.) and Frontlab Team (A.V.-C., C.S., J.G., O.F., B.D., R.L., M.T.), Institut du Cerveau et de la Moelle Epinière (ICM), INSERM 1127, CNRS, UMR 7225 and Sorbonne Université (SO), Paris, France; Laboratory for Cerebral Dynamics Plasticity and Rehabilitation (A.V.-C.), Boston University School of Medicine, MA; Cognitive Neuroscience and Information Technology Research Program (A.V.-C.), Open University of Catalonia (UOC), Barcelona, Spain; Department of Neurology (B.D., R.L., M.T.), National Reference Center for "PPA and Rare Dementias," Pitié Salpêtrière Hospital, AP-HP, Paris, France; and Neural Engineering Laboratory, Department of Biomedical Engineering (D.Q.T., M.B.), the City College of City University of New York, NY
| | - Richard Levy
- From Groupe de Dynamiques Cérébrales, Plasticité et Rééducation (A.V.-C., C.S., J.G., O.F.) and Frontlab Team (A.V.-C., C.S., J.G., O.F., B.D., R.L., M.T.), Institut du Cerveau et de la Moelle Epinière (ICM), INSERM 1127, CNRS, UMR 7225 and Sorbonne Université (SO), Paris, France; Laboratory for Cerebral Dynamics Plasticity and Rehabilitation (A.V.-C.), Boston University School of Medicine, MA; Cognitive Neuroscience and Information Technology Research Program (A.V.-C.), Open University of Catalonia (UOC), Barcelona, Spain; Department of Neurology (B.D., R.L., M.T.), National Reference Center for "PPA and Rare Dementias," Pitié Salpêtrière Hospital, AP-HP, Paris, France; and Neural Engineering Laboratory, Department of Biomedical Engineering (D.Q.T., M.B.), the City College of City University of New York, NY
| | - Dennis Q Truong
- From Groupe de Dynamiques Cérébrales, Plasticité et Rééducation (A.V.-C., C.S., J.G., O.F.) and Frontlab Team (A.V.-C., C.S., J.G., O.F., B.D., R.L., M.T.), Institut du Cerveau et de la Moelle Epinière (ICM), INSERM 1127, CNRS, UMR 7225 and Sorbonne Université (SO), Paris, France; Laboratory for Cerebral Dynamics Plasticity and Rehabilitation (A.V.-C.), Boston University School of Medicine, MA; Cognitive Neuroscience and Information Technology Research Program (A.V.-C.), Open University of Catalonia (UOC), Barcelona, Spain; Department of Neurology (B.D., R.L., M.T.), National Reference Center for "PPA and Rare Dementias," Pitié Salpêtrière Hospital, AP-HP, Paris, France; and Neural Engineering Laboratory, Department of Biomedical Engineering (D.Q.T., M.B.), the City College of City University of New York, NY
| | - Marom Bikson
- From Groupe de Dynamiques Cérébrales, Plasticité et Rééducation (A.V.-C., C.S., J.G., O.F.) and Frontlab Team (A.V.-C., C.S., J.G., O.F., B.D., R.L., M.T.), Institut du Cerveau et de la Moelle Epinière (ICM), INSERM 1127, CNRS, UMR 7225 and Sorbonne Université (SO), Paris, France; Laboratory for Cerebral Dynamics Plasticity and Rehabilitation (A.V.-C.), Boston University School of Medicine, MA; Cognitive Neuroscience and Information Technology Research Program (A.V.-C.), Open University of Catalonia (UOC), Barcelona, Spain; Department of Neurology (B.D., R.L., M.T.), National Reference Center for "PPA and Rare Dementias," Pitié Salpêtrière Hospital, AP-HP, Paris, France; and Neural Engineering Laboratory, Department of Biomedical Engineering (D.Q.T., M.B.), the City College of City University of New York, NY
| | - Marc Teichmann
- From Groupe de Dynamiques Cérébrales, Plasticité et Rééducation (A.V.-C., C.S., J.G., O.F.) and Frontlab Team (A.V.-C., C.S., J.G., O.F., B.D., R.L., M.T.), Institut du Cerveau et de la Moelle Epinière (ICM), INSERM 1127, CNRS, UMR 7225 and Sorbonne Université (SO), Paris, France; Laboratory for Cerebral Dynamics Plasticity and Rehabilitation (A.V.-C.), Boston University School of Medicine, MA; Cognitive Neuroscience and Information Technology Research Program (A.V.-C.), Open University of Catalonia (UOC), Barcelona, Spain; Department of Neurology (B.D., R.L., M.T.), National Reference Center for "PPA and Rare Dementias," Pitié Salpêtrière Hospital, AP-HP, Paris, France; and Neural Engineering Laboratory, Department of Biomedical Engineering (D.Q.T., M.B.), the City College of City University of New York, NY.
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Bikson M, Brunoni AR, Charvet LE, Clark VP, Cohen LG, Deng ZD, Dmochowski J, Edwards DJ, Frohlich F, Kappenman ES, Lim KO, Loo C, Mantovani A, McMullen DP, Parra LC, Pearson M, Richardson JD, Rumsey JM, Sehatpour P, Sommers D, Unal G, Wassermann EM, Woods AJ, Lisanby SH. Rigor and reproducibility in research with transcranial electrical stimulation: An NIMH-sponsored workshop. Brain Stimul 2018; 11:465-480. [PMID: 29398575 PMCID: PMC5997279 DOI: 10.1016/j.brs.2017.12.008] [Citation(s) in RCA: 119] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 12/01/2017] [Accepted: 12/21/2017] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Neuropsychiatric disorders are a leading source of disability and require novel treatments that target mechanisms of disease. As such disorders are thought to result from aberrant neuronal circuit activity, neuromodulation approaches are of increasing interest given their potential for manipulating circuits directly. Low intensity transcranial electrical stimulation (tES) with direct currents (transcranial direct current stimulation, tDCS) or alternating currents (transcranial alternating current stimulation, tACS) represent novel, safe, well-tolerated, and relatively inexpensive putative treatment modalities. OBJECTIVE This report seeks to promote the science, technology and effective clinical applications of these modalities, identify research challenges, and suggest approaches for addressing these needs in order to achieve rigorous, reproducible findings that can advance clinical treatment. METHODS The National Institute of Mental Health (NIMH) convened a workshop in September 2016 that brought together experts in basic and human neuroscience, electrical stimulation biophysics and devices, and clinical trial methods to examine the physiological mechanisms underlying tDCS/tACS, technologies and technical strategies for optimizing stimulation protocols, and the state of the science with respect to therapeutic applications and trial designs. RESULTS Advances in understanding mechanisms, methodological and technological improvements (e.g., electronics, computational models to facilitate proper dosing), and improved clinical trial designs are poised to advance rigorous, reproducible therapeutic applications of these techniques. A number of challenges were identified and meeting participants made recommendations made to address them. CONCLUSIONS These recommendations align with requirements in NIMH funding opportunity announcements to, among other needs, define dosimetry, demonstrate dose/response relationships, implement rigorous blinded trial designs, employ computational modeling, and demonstrate target engagement when testing stimulation-based interventions for the treatment of mental disorders.
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Affiliation(s)
- Marom Bikson
- Department of Biomedical Engineering, The City College of the City University of New York, United States
| | - Andre R Brunoni
- Laboratory of Neurosciences (LIM-27), Department and Institute of Psychiatry, University of Sao Paulo, Sao Paulo, Brazil
| | - Leigh E Charvet
- Department of Neurology, New York University School of Medicine, New York, NY, United States
| | - Vincent P Clark
- Department of Psychology, University of New Mexico, Albuquerque, NM, United States
| | - Leonardo G Cohen
- Human Cortical Physiology and Neurorehabilitation Section, National Institute of Neurological Disorders and Stroke, Bethesda, MD, United States
| | - Zhi-De Deng
- Experimental Therapeutics and Pathophysiology Branch, National Institute of Mental Health, Bethesda, MD, United States
| | - Jacek Dmochowski
- Department of Biomedical Engineering, The City College of the City University of New York, United States
| | - Dylan J Edwards
- Non-invasive Brain Stimulation and Human Motor Control Laboratory, Burke Rehabilitation and Research, Burke-Cornell Medical Research Facility, White Plains, New York and School of Medicine and Health Sciences, Edith Cowan University, Perth, Australia
| | - Flavio Frohlich
- Department of Psychiatry, Cell Biology and Physiology, Biomedical Engineering, and Neurology, Carolina Center for Neurostimulation, University of North Carolina School of Medicine, Chapel Hill, NC, United States
| | - Emily S Kappenman
- Department of Psychology, San Diego State University, San Diego, CA, United States
| | - Kelvin O Lim
- Department of Psychiatry, University of Minnesota, Minneapolis Veterans Administration Health Care System, and Defense Veterans Brain Injury Center, Minneapolis, MN, United States
| | - Colleen Loo
- School of Psychiatry and Black Dog Institute, University of New South Wales, Sydney, Australia
| | - Antonio Mantovani
- Department of Physiology, Pharmacology and Neuroscience, City College of the City University of New York, New York, NY, United States
| | - David P McMullen
- Division of Translational Research, National Institute of Mental Health, Bethesda, MD, United States
| | - Lucas C Parra
- Department of Biomedical Engineering, The City College of the City University of New York, United States
| | - Michele Pearson
- Division of Translational Research, National Institute of Mental Health, Bethesda, MD, United States
| | - Jessica D Richardson
- Department of Speech and Hearing Sciences, University of New Mexico, Albuquerque, NM, United States
| | - Judith M Rumsey
- Division of Translational Research, National Institute of Mental Health, Bethesda, MD, United States.
| | - Pejman Sehatpour
- Department of Psychiatry, Columbia University, New York, NY, United States
| | - David Sommers
- Scientific Review Branch, National Institute of Mental Health, Bethesda, MD, United States
| | - Gozde Unal
- Department of Biomedical Engineering, The City College of the City University of New York, United States
| | - Eric M Wassermann
- Behavioral Neurology Unit, National Institute of Neurological Disorders and Stroke, Bethesda, MD, United States
| | - Adam J Woods
- Department of Clinical and Health Psychology, Center for Cognitive Aging and Memory, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
| | - Sarah H Lisanby
- Division of Translational Research, National Institute of Mental Health, Bethesda, MD, United States
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Mourdoukoutas AP, Truong DQ, Adair DK, Simon BJ, Bikson M. High-Resolution Multi-Scale Computational Model for Non-Invasive Cervical Vagus Nerve Stimulation. Neuromodulation 2018; 21:261-268. [PMID: 29076212 PMCID: PMC5895480 DOI: 10.1111/ner.12706] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 07/26/2017] [Accepted: 08/25/2017] [Indexed: 12/28/2022]
Abstract
OBJECTIVES To develop the first high-resolution, multi-scale model of cervical non-invasive vagus nerve stimulation (nVNS) and to predict vagus fiber type activation, given clinically relevant rheobase thresholds. METHODS An MRI-derived Finite Element Method (FEM) model was developed to accurately simulate key macroscopic (e.g., skin, soft tissue, muscle) and mesoscopic (cervical enlargement, vertebral arch and foramen, cerebral spinal fluid [CSF], nerve sheath) tissue components to predict extracellular potential, electric field (E-Field), and activating function along the vagus nerve. Microscopic scale biophysical models of axons were developed to compare axons of varying size (Aα-, Aβ- and Aδ-, B-, and C-fibers). Rheobase threshold estimates were based on a step function waveform. RESULTS Macro-scale accuracy was found to determine E-Field magnitudes around the vagus nerve, while meso-scale precision determined E-field changes (activating function). Mesoscopic anatomical details that capture vagus nerve passage through a changing tissue environment (e.g., bone to soft tissue) profoundly enhanced predicted axon sensitivity while encapsulation in homogenous tissue (e.g., nerve sheath) dulled axon sensitivity to nVNS. CONCLUSIONS These findings indicate that realistic and precise modeling at both macroscopic and mesoscopic scales are needed for quantitative predictions of vagus nerve activation. Based on this approach, we predict conventional cervical nVNS protocols can activate A- and B- but not C-fibers. Our state-of-the-art implementation across scales is equally valuable for models of spinal cord stimulation, cortex/deep brain stimulation, and other peripheral/cranial nerve models.
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Affiliation(s)
- Antonios P. Mourdoukoutas
- Department of Biomedical Engineering, The City College of New York, City University of New York, New York, NY
| | - Dennis Q. Truong
- Department of Biomedical Engineering, The City College of New York, City University of New York, New York, NY
| | - Devin K. Adair
- Department of Psychology, The Graduate Center, City University of New York, New York, New York
| | | | - Marom Bikson
- Department of Biomedical Engineering, The City College of New York, City University of New York, New York, NY
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Esmaeilpour Z, Marangolo P, Hampstead BM, Bestmann S, Galletta E, Knotkova H, Bikson M. Incomplete evidence that increasing current intensity of tDCS boosts outcomes. Brain Stimul 2017; 11:310-321. [PMID: 29258808 DOI: 10.1016/j.brs.2017.12.002] [Citation(s) in RCA: 124] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 12/06/2017] [Accepted: 12/08/2017] [Indexed: 01/30/2023] Open
Abstract
BACKGROUND Transcranial direct current stimulation (tDCS) is investigated to modulate neuronal function by applying a fixed low-intensity direct current to scalp. OBJECTIVES We critically discuss evidence for a monotonic response in effect size with increasing current intensity, with a specific focus on a question if increasing applied current enhance the efficacy of tDCS. METHODS We analyzed tDCS intensity does-response from different perspectives including biophysical modeling, animal modeling, human neurophysiology, neuroimaging and behavioral/clinical measures. Further, we discuss approaches to design dose-response trials. RESULTS Physical models predict electric field in the brain increases with applied tDCS intensity. Data from animal studies are lacking since a range of relevant low-intensities is rarely tested. Results from imaging studies are ambiguous while human neurophysiology, including using transcranial magnetic stimulation (TMS) as a probe, suggests a complex state-dependent non-monotonic dose response. The diffusivity of brain current flow produced by conventional tDCS montages complicates this analysis, with relatively few studies on focal High Definition (HD)-tDCS. In behavioral and clinical trials, only a limited range of intensities (1-2 mA), and typically just one intensity, are conventionally tested; moreover, outcomes are subject brain-state dependent. Measurements and models of current flow show that for the same applied current, substantial differences in brain current occur across individuals. Trials are thus subject to inter-individual differences that complicate consideration of population-level dose response. CONCLUSION The presence or absence of simple dose response does not impact how efficacious a given tDCS dose is for a given indication. Understanding dose-response in human applications of tDCS is needed for protocol optimization including individualized dose to reduce outcome variability, which requires intelligent design of dose-response studies.
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Affiliation(s)
- Zeinab Esmaeilpour
- Department of Biomedical Engineering, The City College of New York of CUNY, New York, NY 10031, USA; Biomedical Engineering Department, Amirkabir University of Technology, Tehran, Iran.
| | - Paola Marangolo
- Dipartimento di Studi Umanistici, University Federico II, Naples and IRCCS Fondazione Santa Lucia, Rome Italy
| | - Benjamin M Hampstead
- VA Ann Arbor Healthcare System, Ann Arbor, MI 48105, USA; Department of Psychiatry, University of Michigan, Ann Arbor, MI 48105, USA
| | - Sven Bestmann
- Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, University College London, UK
| | - Elisabeth Galletta
- Rusk Rehabilitation Medicine, New York University Langone Medical Center, USA
| | - Helena Knotkova
- MJHS Institute for Innovation in Palliative Care, New York, NY, USA; Department of Family and Social Medicine, Albert Einstein College of Medicine, The Bronx, NY, USA
| | - Marom Bikson
- Department of Biomedical Engineering, The City College of New York of CUNY, New York, NY 10031, USA
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Leite J, Gonçalves ÓF, Pereira P, Khadka N, Bikson M, Fregni F, Carvalho S. The differential effects of unihemispheric and bihemispheric tDCS over the inferior frontal gyrus on proactive control. Neurosci Res 2017; 130:39-46. [PMID: 28842243 DOI: 10.1016/j.neures.2017.08.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 08/14/2017] [Accepted: 08/18/2017] [Indexed: 01/19/2023]
Abstract
This study examined the effects of bihemispheric and unihemispheric transcranial Direct Current Stimulation (tDCS) over the inferior frontal gyrus (IFG) on proactive control. Sixteen participants were randomized to receive (i) bihemispheric tDCS, with a 35cm2 anodal electrode of the right IFG and a 35cm2 cathode electrode of left IFG or (ii) unihemispheric tDCS, with a 35cm2 anodal electrode of the right IFG and a 100cm2 electrode of the left IFG or (iii) sham tDCS, while performing a prepotent inhibition task. There were significant speed-accuracy tradeoff effects in terms of switch costs: unihemispheric tDCS significantly decreased the accuracy when compared to bihemispheric, and sham tDCS, while increased response time when comparing to bihemispheric and sham tDCS. The computational model showed a symmetrical field intensity for the bihemispheric tDCS montage, and an asymmetrical for the unihemispheric tDCS montage. This study confirms that unihemispheric tDCS over the rIFG has a significant impact on response inhibition. The lack of results of bihemispheric tDCS brings two important findings for this study: (i) left IFG seems to be also critically associated with inhibitory response control, and (ii) these results highlight the importance of considering the dual effects of tDCS when choosing the electrode montage.
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Affiliation(s)
- Jorge Leite
- Neuropsychophysiology Laboratory, CIPsi, School of Psychology (EPsi), University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; Univ Portucalense, Portucalense Institute for Human Development - INPP, Oporto, Portugal; Spaulding Neuromodulation Center, Department of Physical Medicine and Rehabilitation, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
| | - Óscar F Gonçalves
- Neuropsychophysiology Laboratory, CIPsi, School of Psychology (EPsi), University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; Spaulding Neuromodulation Center, Department of Physical Medicine and Rehabilitation, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Patrícia Pereira
- Neuropsychophysiology Laboratory, CIPsi, School of Psychology (EPsi), University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal
| | - Niranjan Khadka
- Department of Biomedical Engineering, The City College of New York of CUNY, New York, NY, 10031 USA
| | - Marom Bikson
- Department of Biomedical Engineering, The City College of New York of CUNY, New York, NY, 10031 USA
| | - Felipe Fregni
- Spaulding Neuromodulation Center, Department of Physical Medicine and Rehabilitation, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Sandra Carvalho
- Neuropsychophysiology Laboratory, CIPsi, School of Psychology (EPsi), University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; Spaulding Neuromodulation Center, Department of Physical Medicine and Rehabilitation, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
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30
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Schweizer LM, Zahn PK, Pogatzki-Zahn EM, Magerl W, Tegenthoff M, Meyer-Frießem CH. Influence of transcutaneous spinal stimulation on human LTP-like pain amplification. A randomized, double-blind study in volunteers. Clin Neurophysiol 2017; 128:1413-1420. [PMID: 28618292 DOI: 10.1016/j.clinph.2017.05.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2016] [Revised: 04/30/2017] [Accepted: 05/08/2017] [Indexed: 02/05/2023]
Abstract
OBJECTIVE Transcutaneous spinal direct current stimulation (tsDCS) has been proven to affect nociceptive signal processing. We designed a randomized, double-blind, cross-over study to investigate whether tsDCS applied before or after inducing long-term potentiation-(LTP)-like hyperalgesia may decrease nociceptive sensitivity. METHODS In healthy volunteers, tsDCS (2.5mA, 15min) was applied to the thoracic spine prior (n=14) or immediately following (n=12) electrical high-frequency stimulation (HFS) to the thigh, inducing hyperalgesia. Mechanical and electrical perception were assessed before HFS stimulation and at three time points following HFS stimulation (all within 90min of HFS). Subjects took part in three separate sessions to test effects of anodal, cathodal, or sham tsDCS. RESULTS Within 60minHFS led to unilateral changes on the conditioned side: mechanical pain thresholds tended to decrease and electrical detection thresholds significantly decreased (p<0.001); pain ratings measured using the numerical rating scale (NRS) increased for electrical stimuli (p<0.01) and two categories of mechanical stimuli ("Light(8-64mN)": p=ns; "Heavy(128-512mN)": p<0.01). Irrespective of stimulation order or polarity, tsDCS could not influence nociceptive sensitivity. CONCLUSION Hyperalgesia was adequately induced, but tsDCS had no effect on HFS-induced sensitization. SIGNIFICANCE While tsDCS has been shown to affect pain measures, our results suggest irrespective of time of stimulation or polarity that tsDCS may be less effective in modulating pain in a sensitized state in healthy subjects.
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Affiliation(s)
- L M Schweizer
- Department of Neurology, Ruhr-University Bochum, BG-Kliniken Bergmannsheil, Bürkle-de-la-Camp-Platz 1, 44789 Bochum, Germany
| | - P K Zahn
- Department of Anaesthesiology, Intensive Care Medicine, Palliative Care Medicine and Pain Management, Medical Faculty of Ruhr-University, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH Bochum, Bürkle-de-la-Camp-Platz 1, 44789 Bochum, Germany
| | - E M Pogatzki-Zahn
- Department of Anaesthesiology, Intensive Care and Pain Medicine, University Hospital of Muenster, Albert-Schweitzer-Campus 1 (Building A1), 48149 Münster, Germany
| | - W Magerl
- Department of Neurophysiology, Center of Biomedicine and Medical Technology (CBTM), Medical Faculty Mannheim, Ruprecht-Karls-University Heidelberg, Ludolf-Krehl-Str. 13, 68167 Mannheim, Germany
| | - M Tegenthoff
- Department of Neurology, Ruhr-University Bochum, BG-Kliniken Bergmannsheil, Bürkle-de-la-Camp-Platz 1, 44789 Bochum, Germany
| | - C H Meyer-Frießem
- Department of Anaesthesiology, Intensive Care Medicine, Palliative Care Medicine and Pain Management, Medical Faculty of Ruhr-University, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH Bochum, Bürkle-de-la-Camp-Platz 1, 44789 Bochum, Germany.
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Karamintziou SD, Custódio AL, Piallat B, Polosan M, Chabardès S, Stathis PG, Tagaris GA, Sakas DE, Polychronaki GE, Tsirogiannis GL, David O, Nikita KS. Algorithmic design of a noise-resistant and efficient closed-loop deep brain stimulation system: A computational approach. PLoS One 2017; 12:e0171458. [PMID: 28222198 PMCID: PMC5319757 DOI: 10.1371/journal.pone.0171458] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 01/20/2017] [Indexed: 11/19/2022] Open
Abstract
Advances in the field of closed-loop neuromodulation call for analysis and modeling approaches capable of confronting challenges related to the complex neuronal response to stimulation and the presence of strong internal and measurement noise in neural recordings. Here we elaborate on the algorithmic aspects of a noise-resistant closed-loop subthalamic nucleus deep brain stimulation system for advanced Parkinson’s disease and treatment-refractory obsessive-compulsive disorder, ensuring remarkable performance in terms of both efficiency and selectivity of stimulation, as well as in terms of computational speed. First, we propose an efficient method drawn from dynamical systems theory, for the reliable assessment of significant nonlinear coupling between beta and high-frequency subthalamic neuronal activity, as a biomarker for feedback control. Further, we present a model-based strategy through which optimal parameters of stimulation for minimum energy desynchronizing control of neuronal activity are being identified. The strategy integrates stochastic modeling and derivative-free optimization of neural dynamics based on quadratic modeling. On the basis of numerical simulations, we demonstrate the potential of the presented modeling approach to identify, at a relatively low computational cost, stimulation settings potentially associated with a significantly higher degree of efficiency and selectivity compared with stimulation settings determined post-operatively. Our data reinforce the hypothesis that model-based control strategies are crucial for the design of novel stimulation protocols at the backstage of clinical applications.
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Affiliation(s)
- Sofia D. Karamintziou
- School of Electrical and Computer Engineering, National Technical University of Athens, Athens, Greece
- Department of Mechanical Engineering, University of California, Riverside, California, United States of America
- * E-mail: (SDK); (KSN)
| | | | - Brigitte Piallat
- Univ. Grenoble Alpes, Grenoble Institut des Neurosciences, GIN, Grenoble, France
- Inserm, U1216, Grenoble, France
| | - Mircea Polosan
- Inserm, U1216, Grenoble, France
- Department of Psychiatry, University Hospital of Grenoble, Grenoble, France
| | - Stéphan Chabardès
- Univ. Grenoble Alpes, Grenoble Institut des Neurosciences, GIN, Grenoble, France
- Inserm, U1216, Grenoble, France
- Department of Neurosurgery, University Hospital of Grenoble, Grenoble, France
| | | | - George A. Tagaris
- Department of Neurology, ‘G. Gennimatas’ General Hospital of Athens, Athens, Greece
| | - Damianos E. Sakas
- Department of Neurosurgery, University of Athens Medical School, ‘Evangelismos’ General Hospital, Athens, Greece
| | - Georgia E. Polychronaki
- School of Electrical and Computer Engineering, National Technical University of Athens, Athens, Greece
| | - George L. Tsirogiannis
- School of Electrical and Computer Engineering, National Technical University of Athens, Athens, Greece
| | - Olivier David
- Univ. Grenoble Alpes, Grenoble Institut des Neurosciences, GIN, Grenoble, France
- Inserm, U1216, Grenoble, France
| | - Konstantina S. Nikita
- School of Electrical and Computer Engineering, National Technical University of Athens, Athens, Greece
- * E-mail: (SDK); (KSN)
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Bonaiuto JJ, de Berker A, Bestmann S. Response repetition biases in human perceptual decisions are explained by activity decay in competitive attractor models. eLife 2016; 5:e20047. [PMID: 28005007 PMCID: PMC5243027 DOI: 10.7554/elife.20047] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 12/19/2016] [Indexed: 12/21/2022] Open
Abstract
Animals and humans have a tendency to repeat recent choices, a phenomenon known as choice hysteresis. The mechanism for this choice bias remains unclear. Using an established, biophysically informed model of a competitive attractor network for decision making, we found that decaying tail activity from the previous trial caused choice hysteresis, especially during difficult trials, and accurately predicted human perceptual choices. In the model, choice variability could be directionally altered through amplification or dampening of post-trial activity decay through simulated depolarizing or hyperpolarizing network stimulation. An analogous intervention using transcranial direct current stimulation (tDCS) over left dorsolateral prefrontal cortex (dlPFC) yielded a close match between model predictions and experimental results: net soma depolarizing currents increased choice hysteresis, while hyperpolarizing currents suppressed it. Residual activity in competitive attractor networks within dlPFC may thus give rise to biases in perceptual choices, which can be directionally controlled through non-invasive brain stimulation.
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Affiliation(s)
- James J Bonaiuto
- Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, University College London, London, United Kingdom
| | - Archy de Berker
- Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, University College London, London, United Kingdom
| | - Sven Bestmann
- Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, University College London, London, United Kingdom
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Alonzo A, Aaronson S, Bikson M, Husain M, Lisanby S, Martin D, McClintock SM, McDonald WM, O'Reardon J, Esmailpoor Z, Loo C. Study design and methodology for a multicentre, randomised controlled trial of transcranial direct current stimulation as a treatment for unipolar and bipolar depression. Contemp Clin Trials 2016; 51:65-71. [DOI: 10.1016/j.cct.2016.10.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 10/04/2016] [Accepted: 10/10/2016] [Indexed: 01/17/2023]
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Jackson MP, Rahman A, Lafon B, Kronberg G, Ling D, Parra LC, Bikson M. Animal models of transcranial direct current stimulation: Methods and mechanisms. Clin Neurophysiol 2016; 127:3425-3454. [PMID: 27693941 PMCID: PMC5083183 DOI: 10.1016/j.clinph.2016.08.016] [Citation(s) in RCA: 186] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Revised: 08/05/2016] [Accepted: 08/08/2016] [Indexed: 12/28/2022]
Abstract
The objective of this review is to summarize the contribution of animal research using direct current stimulation (DCS) to our understanding of the physiological effects of transcranial direct current stimulation (tDCS). We comprehensively address experimental methodology in animal studies, broadly classified as: (1) transcranial stimulation; (2) direct cortical stimulation in vivo and (3) in vitro models. In each case advantages and disadvantages for translational research are discussed including dose translation and the overarching "quasi-uniform" assumption, which underpins translational relevance in all animal models of tDCS. Terminology such as anode, cathode, inward current, outward current, current density, electric field, and uniform are defined. Though we put key animal experiments spanning decades in perspective, our goal is not simply an exhaustive cataloging of relevant animal studies, but rather to put them in context of ongoing efforts to improve tDCS. Cellular targets, including excitatory neuronal somas, dendrites, axons, interneurons, glial cells, and endothelial cells are considered. We emphasize neurons are always depolarized and hyperpolarized such that effects of DCS on neuronal excitability can only be evaluated within subcellular regions of the neuron. Findings from animal studies on the effects of DCS on plasticity (LTP/LTD) and network oscillations are reviewed extensively. Any endogenous phenomena dependent on membrane potential changes are, in theory, susceptible to modulation by DCS. The relevance of morphological changes (galvanotropy) to tDCS is also considered, as we suggest microscopic migration of axon terminals or dendritic spines may be relevant during tDCS. A majority of clinical studies using tDCS employ a simplistic dose strategy where excitability is singularly increased or decreased under the anode and cathode, respectively. We discuss how this strategy, itself based on classic animal studies, cannot account for the complexity of normal and pathological brain function, and how recent studies have already indicated more sophisticated approaches are necessary. One tDCS theory regarding "functional targeting" suggests the specificity of tDCS effects are possible by modulating ongoing function (plasticity). Use of animal models of disease are summarized including pain, movement disorders, stroke, and epilepsy.
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Affiliation(s)
- Mark P Jackson
- Department of Biomedical Engineering, The City College of The City University of New York, NY, USA
| | - Asif Rahman
- Department of Biomedical Engineering, The City College of The City University of New York, NY, USA
| | - Belen Lafon
- Department of Biomedical Engineering, The City College of The City University of New York, NY, USA
| | - Gregory Kronberg
- Department of Biomedical Engineering, The City College of The City University of New York, NY, USA
| | - Doris Ling
- Department of Biomedical Engineering, The City College of The City University of New York, NY, USA
| | - Lucas C Parra
- Department of Biomedical Engineering, The City College of The City University of New York, NY, USA
| | - Marom Bikson
- Department of Biomedical Engineering, The City College of The City University of New York, NY, USA.
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Adaptive Plasticity in the Healthy Language Network: Implications for Language Recovery after Stroke. Neural Plast 2016; 2016:9674790. [PMID: 27830094 PMCID: PMC5088318 DOI: 10.1155/2016/9674790] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 09/18/2016] [Accepted: 09/25/2016] [Indexed: 12/27/2022] Open
Abstract
Across the last three decades, the application of noninvasive brain stimulation (NIBS) has substantially increased the current knowledge of the brain's potential to undergo rapid short-term reorganization on the systems level. A large number of studies applied transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS) in the healthy brain to probe the functional relevance and interaction of specific areas for different cognitive processes. NIBS is also increasingly being used to induce adaptive plasticity in motor and cognitive networks and shape cognitive functions. Recently, NIBS has been combined with electrophysiological techniques to modulate neural oscillations of specific cortical networks. In this review, we will discuss recent advances in the use of NIBS to modulate neural activity and effective connectivity in the healthy language network, with a special focus on the combination of NIBS and neuroimaging or electrophysiological approaches. Moreover, we outline how these results can be transferred to the lesioned brain to unravel the dynamics of reorganization processes in poststroke aphasia. We conclude with a critical discussion on the potential of NIBS to facilitate language recovery after stroke and propose a phase-specific model for the application of NIBS in language rehabilitation.
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Teichmann M, Lesoil C, Godard J, Vernet M, Bertrand A, Levy R, Dubois B, Lemoine L, Truong DQ, Bikson M, Kas A, Valero-Cabré A. Direct current stimulation over the anterior temporal areas boosts semantic processing in primary progressive aphasia. Ann Neurol 2016; 80:693-707. [PMID: 27553723 DOI: 10.1002/ana.24766] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Revised: 08/19/2016] [Accepted: 08/19/2016] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Noninvasive brain stimulation in primary progressive aphasia (PPA) is a promising approach. Yet, applied to single cases or insufficiently controlled small-cohort studies, it has not clarified its therapeutic value. We here address the effectiveness of transcranial direct current stimulation (tDCS) on the semantic PPA variant (sv-PPA), applying a rigorous study design to a large, homogeneous sv-PPA cohort. METHODS Using a double-blind, sham-controlled counterbalanced cross-over design, we applied three tDCS conditions targeting the temporal poles of 12 sv-PPA patients. Efficiency was assessed by a semantic matching task orthogonally manipulating "living"/"nonliving" categories and verbal/visual modalities. Conforming to predominantly left-lateralized damage in sv-PPA and accounts of interhemispheric inhibition, we applied left hemisphere anodal-excitatory and right hemisphere cathodal-inhibitory tDCS, compared to sham stimulation. RESULTS Prestimulation data, compared to 15 healthy controls, showed that patients had semantic disorders predominating with living categories in the verbal modality. Stimulation selectively impacted these most impaired domains: Left-excitatory and right-inhibitory tDCS improved semantic accuracy in verbal modality, and right-inhibitory tDCS improved processing speed with living categories and accuracy and processing speed in the combined verbal × living condition. INTERPRETATION Our findings demonstrate the efficiency of tDCS in sv-PPA by generating highly specific intrasemantic effects. They provide "proof of concept" for future applications of tDCS in therapeutic multiday regimes, potentially driving sustained improvement of semantic processing. Our data also support the hotly debated existence of a left temporal-pole network for verbal semantics selectively modulated through both left-excitatory and right-inhibitory brain stimulation. Ann Neurol 2016;80:693-707.
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Affiliation(s)
- Marc Teichmann
- Department of Neurology, National Reference Center for "PPA and rare dementias", Pitié Salpêtrière Hospital, AP-HP, Paris, France.,Brain & Spine Institute, ICM-UMR INSERM-CNRS-UPMC 1127, Frontlab team, Paris, France
| | - Constance Lesoil
- Department of Neurology, National Reference Center for "PPA and rare dementias", Pitié Salpêtrière Hospital, AP-HP, Paris, France.,Brain & Spine Institute, ICM-UMR INSERM-CNRS-UPMC 1127, Frontlab team, Paris, France
| | - Juliette Godard
- Brain & Spine Institute, ICM-UMR INSERM-CNRS-UPMC 1127, Frontlab team, Paris, France.,Brain & Spine Institute, UMR INSERM-CNRS-UPMC 1127, Team of Cerebral Dynamics Plasticity & Rehabilitation, Paris, France.,Laboratory for Cerebral Dynamics Plasticity & Rehabilitation, Boston University School of Medicine, Boston, MA
| | - Marine Vernet
- Brain & Spine Institute, ICM-UMR INSERM-CNRS-UPMC 1127, Frontlab team, Paris, France.,Brain & Spine Institute, UMR INSERM-CNRS-UPMC 1127, Team of Cerebral Dynamics Plasticity & Rehabilitation, Paris, France
| | - Anne Bertrand
- Department of diagnostic and functional neuroradiology, Pitié-Salpêtrière Hospital, AP-HP, Paris, France
| | - Richard Levy
- Brain & Spine Institute, ICM-UMR INSERM-CNRS-UPMC 1127, Frontlab team, Paris, France.,Department of Neurology, Saint Antoine Hospital, AP-HP, Paris, France
| | - Bruno Dubois
- Department of Neurology, National Reference Center for "PPA and rare dementias", Pitié Salpêtrière Hospital, AP-HP, Paris, France.,Brain & Spine Institute, ICM-UMR INSERM-CNRS-UPMC 1127, Frontlab team, Paris, France
| | - Laurie Lemoine
- Department of Neurology, Henri Mondor Hospital, AP-HP & Mondor Institute of biomedical research, INSERM U955 - Team 1, Créteil, France
| | - Dennis Q Truong
- Neural Engineering Laboratory, Department of Biomedical Engineering, The City College of New York, City University of New York, New York, NY
| | - Marom Bikson
- Neural Engineering Laboratory, Department of Biomedical Engineering, The City College of New York, City University of New York, New York, NY
| | - Aurélie Kas
- Nuclear Medicine Department, Pitié-Salpêtrière Hospital, AP-HP & Pierre et Marie Curie University, LIB-INSERM UMR 678, Paris, France
| | - Antoni Valero-Cabré
- Brain & Spine Institute, ICM-UMR INSERM-CNRS-UPMC 1127, Frontlab team, Paris, France.,Brain & Spine Institute, UMR INSERM-CNRS-UPMC 1127, Team of Cerebral Dynamics Plasticity & Rehabilitation, Paris, France.,Laboratory for Cerebral Dynamics Plasticity & Rehabilitation, Boston University School of Medicine, Boston, MA.,Cognitive Neuroscience and Information Technology Research Program, Open University of Catalonia (UOC), Barcelona, Spain
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Alam M, Truong DQ, Khadka N, Bikson M. Spatial and polarity precision of concentric high-definition transcranial direct current stimulation (HD-tDCS). Phys Med Biol 2016; 61:4506-21. [DOI: 10.1088/0031-9155/61/12/4506] [Citation(s) in RCA: 99] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Hämmerer D, Bonaiuto J, Klein-Flügge M, Bikson M, Bestmann S. Selective alteration of human value decisions with medial frontal tDCS is predicted by changes in attractor dynamics. Sci Rep 2016; 6:25160. [PMID: 27146700 PMCID: PMC4857193 DOI: 10.1038/srep25160] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 03/04/2016] [Indexed: 02/02/2023] Open
Abstract
During value-based decision making, ventromedial prefrontal cortex (vmPFC) is thought to support choices by tracking the expected gain from different outcomes via a competition-based process. Using a computational neurostimulation approach we asked how perturbing this region might alter this competition and resulting value decisions. We simulated a perturbation of neural dynamics in a biophysically informed model of decision-making through in silico depolarization at the level of neuronal ensembles. Simulated depolarization increased baseline firing rates of pyramidal neurons, which altered their susceptibility to background noise, and thereby increased choice stochasticity. These behavioural predictions were compared to choice behaviour in healthy participants performing similar value decisions during transcranial direct current stimulation (tDCS), a non-invasive brain stimulation technique. We placed the soma depolarizing electrode over medial frontal PFC. In line with model predictions, this intervention resulted in more random choices. By contrast, no such effect was observed when placing the depolarizing electrode over lateral PFC. Using a causal manipulation of ventromedial and lateral prefrontal function, these results provide support for competition-based choice dynamics in human vmPFC, and introduce computational neurostimulation as a mechanistic assay for neurostimulation studies of cognition.
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Affiliation(s)
- D. Hämmerer
- Institute of Cognitive Neuroscience, London, United Kingdom
- Lifespan Psychology, MPI for Human Development, Berlin, Germany
| | - J. Bonaiuto
- Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, University College London, London, United Kingdom
| | - M. Klein-Flügge
- Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, University College London, London, United Kingdom
- Department of Experimental Psychology, Oxford, United Kingdom
| | - M. Bikson
- Department for Biomedical Engineering, The City University of New York, New York, NY, USA
| | - S. Bestmann
- Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, University College London, London, United Kingdom
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Bestmann S. Computational neurostimulation in basic and translational research. PROGRESS IN BRAIN RESEARCH 2015; 222:xv-xx. [PMID: 26541385 DOI: 10.1016/s0079-6123(15)00159-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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