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Cappon DB, Pascual-Leone A. Toward Precision Noninvasive Brain Stimulation. Am J Psychiatry 2024; 181:795-805. [PMID: 39217436 DOI: 10.1176/appi.ajp.20240643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 09/04/2024]
Affiliation(s)
- Davide B Cappon
- Hinda and Arthur Marcus Institute for Aging Research and Deanna and Sidney Wolk Center for Memory Health, Hebrew SeniorLife, Boston; Department of Neurology, Harvard Medical School, Boston
| | - Alvaro Pascual-Leone
- Hinda and Arthur Marcus Institute for Aging Research and Deanna and Sidney Wolk Center for Memory Health, Hebrew SeniorLife, Boston; Department of Neurology, Harvard Medical School, Boston
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Duffy MJ, Feltman KA, Kelley AM, Mackie R. Limitations associated with transcranial direct current stimulation for enhancement: considerations of performance tradeoffs in active-duty Soldiers. Front Hum Neurosci 2024; 18:1444450. [PMID: 39132676 PMCID: PMC11310018 DOI: 10.3389/fnhum.2024.1444450] [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: 06/05/2024] [Accepted: 07/03/2024] [Indexed: 08/13/2024] Open
Abstract
Introduction Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation method, popular due to its low cost, ease-of-application, and portability. As such, it has gained traction in examining its potential for cognitive enhancement in a diverse range of populations, including active-duty military. However, current literature presents mixed results regarding its efficacy and limited evaluations of possible undesirable side-effects (such as degradation to cognitive processes). Methods To further examine its potential for enhancing cognition, a double-blind, randomized, sham-controlled, within-subjects design, was used to evaluate both online active-anodal and -cathodal on several cognitive tasks administered. Potential undesirable side effects related to mood, sleepiness, and cognitive performance, were also assessed. Active tDCS was applied for 30 min, using 2 mA, to the left dorsolateral prefrontal cortex with an extracephalic reference placed on the contralateral arm of 27 (14 males) active-duty Soldiers. Results We report mixed results. Specifically, we found improvements in sustained attention (active-anodal) for males in reaction time (p = 0.024, ηp 2 = 0.16) and for sensitivity index in females (p = 0.013, ηp 2 = 0.18). In addition, we found faster reaction time (p = 0.034, ηp 2 = 0.15) and increased accuracy (p = 0.029, ηp 2 = 0.16) associated with executive function (active-anodal and -cathodal), and worsened working memory performance (active-cathodal; p = 0.008, ηp 2 = 0.18). Additionally, we found increased risk-taking with active-anodal (p = 0.001, ηp 2 = 0.33). Discussion tDCS may hold promise as a method for cognitive enhancement, as evidenced by our findings related to sustained attention and executive function. However, we caution that further study is required to better understand additional parameters and limitations that may explain results, as our study only focused on anode vs. cathode stimulation. Risk-taking was examined secondary to our main interests which warrants further experimental investigation isolating potential tradeoffs that may be associated with tDCS simulation.
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Affiliation(s)
- Michelle J. Duffy
- U.S. Army Aeromedical Research Laboratory, Fort Novosel, AL, United States
- Oak Ridge Institute for Science and Education, Oak Ridge, TN, United States
| | - Kathryn A. Feltman
- U.S. Army Aeromedical Research Laboratory, Fort Novosel, AL, United States
| | - Amanda M. Kelley
- U.S. Army Aeromedical Research Laboratory, Fort Novosel, AL, United States
| | - Ryan Mackie
- U.S. Army Aeromedical Research Laboratory, Fort Novosel, AL, United States
- Oak Ridge Institute for Science and Education, Oak Ridge, TN, United States
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Lee TW, Tramontano G. Neural consequences of 5-Hz transcranial alternating current stimulation over right hemisphere: An eLORETA EEG study. Neurosci Lett 2024; 835:137849. [PMID: 38825146 DOI: 10.1016/j.neulet.2024.137849] [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: 02/22/2024] [Revised: 05/06/2024] [Accepted: 05/30/2024] [Indexed: 06/04/2024]
Abstract
INTRODUCTION Transcranial alternating current stimulation (tACS) at 5-Hz to the right hemisphere can effectively alleviate anxiety symptoms. This study aimed to explore the neural mechanisms that drive the therapeutic benefits. METHODS We collected electroencephalography (EEG) data from 24 participants with anxiety disorders before and after a tACS treatment session. tACS was applied over the right hemisphere, with 1.0 mA at F4, 1.0 mA at P4, and 2.0 mA at T8 (10-10 EEG convention). With eLORETA, we transformed the scalp signals into the current source density in the cortex. We then assessed the differences between post- and pre-treatment brain maps across multiple spectra (delta to low gamma) with non-parametric statistics. RESULTS We observed a trend of heightened power in alpha and reduced power in mid-to-high beta and low gamma, in accord with the EEG markers of anxiolytic effects reported in previous studies. Additionally, we observed a consistent trend of de-synchronization at the stimulating sites across spectra. CONCLUSION tACS 5-Hz over the right hemisphere demonstrated EEG markers of anxiety reduction. The after-effects of tACS on the brain are intricate and cannot be explained solely by the widely circulated entrainment theory. Rather, our results support the involvement of plasticity mechanisms in the offline effects of tACS.
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Affiliation(s)
- Tien-Wen Lee
- The NeuroCognitive Institute (NCI) Clinical Research Foundation, NJ 07856, USA
| | - Gerald Tramontano
- The NeuroCognitive Institute (NCI) Clinical Research Foundation, NJ 07856, USA.
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Münchau A, Klein C, Beste C. Rethinking Movement Disorders. Mov Disord 2024; 39:472-484. [PMID: 38196315 DOI: 10.1002/mds.29706] [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: 07/05/2023] [Revised: 11/16/2023] [Accepted: 12/15/2023] [Indexed: 01/11/2024] Open
Abstract
At present, clinical practice and research in movement disorders (MDs) focus on the "normalization" of altered movements. In this review, rather than concentrating on problems and burdens people with MDs undoubtedly have, we highlight their hidden potentials. Starting with current definitions of Parkinson's disease (PD), dystonia, chorea, and tics, we outline that solely conceiving these phenomena as signs of dysfunction falls short of their complex nature comprising both problems and potentials. Such potentials can be traced and understood in light of well-established cognitive neuroscience frameworks, particularly ideomotor principles, and their influential modern derivatives. Using these frameworks, the wealth of data on altered perception-action integration in the different MDs can be explained and systematized using the mechanism-oriented concept of perception-action binding. According to this concept, MDs can be understood as phenomena requiring and fostering flexible modifications of perception-action associations. Consequently, although conceived as being caught in a (trough) state of deficits, given their high flexibility, people with MDs also have high potential to switch to (adaptive) peak activity that can be conceptualized as hidden potentials. Currently, clinical practice and research in MDs are concerned with deficits and thus the "deep and wide troughs," whereas "scattered narrow peaks" reflecting hidden potentials are neglected. To better delineate and utilize the latter to alleviate the burden of affected people, and destigmatize their conditions, we suggest some measures, including computational modeling combined with neurophysiological methods and tailored treatment. © 2024 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Alexander Münchau
- Institute of Systems Motor Science, University of Lübeck, Lübeck, Germany
| | - Christine Klein
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Christian Beste
- Cognitive Neurophysiology, Department of Child and Adolescent Psychiatry, Faculty of Medicine, TU Dresden, Dresden, Germany
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Cappon D, Fox R, den Boer T, Yu W, LaGanke N, Cattaneo G, Perellón-Alfonso R, Bartrés-Faz D, Manor B, Pascual-Leone A. Tele-supervised home-based transcranial alternating current stimulation (tACS) for Alzheimer's disease: a pilot study. Front Hum Neurosci 2023; 17:1168673. [PMID: 37333833 PMCID: PMC10272342 DOI: 10.3389/fnhum.2023.1168673] [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: 02/17/2023] [Accepted: 04/27/2023] [Indexed: 06/20/2023] Open
Abstract
Background Over 55 million people worldwide are currently diagnosed with Alzheimer's disease (AD) and live with debilitating episodic memory deficits. Current pharmacological treatments have limited efficacy. Recently, transcranial alternating current stimulation (tACS) has shown memory improvement in AD by normalizing high-frequency neuronal activity. Here we investigate the feasibility, safety, and preliminary effects on episodic memory of an innovative protocol where tACS is administered within the homes of older adults with AD with the help of a study companion (HB-tACS). Methods Eight participants diagnosed with AD underwent multiple consecutive sessions of high-definition HB-tACS (40 Hz, 20-min) targeting the left angular gyrus (AG), a key node of the memory network. The Acute Phase comprised 14-weeks of HB-tACS with at least five sessions per week. Three participants underwent resting state electroencephalography (EEG) before and after the 14-week Acute Phase. Subsequently, participants completed a 2-3-month Hiatus Phase not receiving HB-tACS. Finally, in the Taper phase, participants received 2-3 sessions per week over 3-months. Primary outcomes were safety, as determined by the reporting of side effects and adverse events, and feasibility, as determined by adherence and compliance with the study protocol. Primary clinical outcomes were memory and global cognition, measured with the Memory Index Score (MIS) and Montreal Cognitive Assessment (MoCA), respectively. Secondary outcome was EEG theta/gamma ratio. Results reported as mean ± SD. Results All participants completed the study, with an average of 97 HB-tACS sessions completed by each participant; reporting mild side effects during 25% of sessions, moderate during 5%, and severe during 1%. Acute Phase adherence was 98 ± 6.8% and Taper phase was 125 ± 22.3% (rates over 100% indicates participants completed more than the minimum of 2/week). After the Acute Phase, all participants showed memory improvement, MIS of 7.25 ± 3.77, sustained during Hiatus 7.00 ± 4.90 and Taper 4.63 ± 2.39 Phases compared to baseline. For the three participants that underwent EEG, a decreased theta/gamma ratio in AG was observed. Conversely, participants did not show improvement in the MoCA, 1.13 ± 3.80 after the Acute Phase, and there was a modest decrease during the Hiatus -0.64 ± 3.28 and Taper -2.56 ± 5.03 Phases. Conclusion This pilot study shows that the home-based, remotely-supervised, study companion administered, multi-channel tACS protocol for older adults with AD was feasible and safe. Further, targeting the left AG, memory in this sample was improved. These are preliminary results that warrant larger more definite trials to further elucidate tolerability and efficacy of the HB-tACS intervention. NCT04783350. Clinical trial registration https://clinicaltrials.gov/ct2/show/NCT04783350?term=NCT04783350&draw=2&rank=1, identifier NCT04783350.
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Affiliation(s)
- Davide Cappon
- Hinda and Arthur Marcus Institute for Aging Research at Hebrew SeniorLife, Boston, MA, United States
- Deanna and Sidney Wolk Center for Memory Health at Hebrew SeniorLife, Boston, MA, United States
- Department of Neurology, Harvard Medical School, Boston, MA, United States
| | - Rachel Fox
- Hinda and Arthur Marcus Institute for Aging Research at Hebrew SeniorLife, Boston, MA, United States
- Deanna and Sidney Wolk Center for Memory Health at Hebrew SeniorLife, Boston, MA, United States
| | - Tim den Boer
- Hinda and Arthur Marcus Institute for Aging Research at Hebrew SeniorLife, Boston, MA, United States
| | - Wanting Yu
- Hinda and Arthur Marcus Institute for Aging Research at Hebrew SeniorLife, Boston, MA, United States
| | - Nicole LaGanke
- Hinda and Arthur Marcus Institute for Aging Research at Hebrew SeniorLife, Boston, MA, United States
| | - Gabriele Cattaneo
- Institut Guttmann, Institut Universitari de Neurorehabilitació Adscrit a la UAB, Barcelona, Spain
- Departament de Medicina, Universitat Autònoma de Barcelona, Bellaterra, Spain
- Fundació Institut d’Investigació en Ciències de la Salut Germans Trias i Pujol, Badalona, Spain
| | - Ruben Perellón-Alfonso
- Department of Medicine, Faculty of Medicine and Health Sciences, Institute of Neurosciences, University of Barcelona, Barcelona, Spain
- Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - David Bartrés-Faz
- Department of Medicine, Faculty of Medicine and Health Sciences, Institute of Neurosciences, University of Barcelona, Barcelona, Spain
- Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Brad Manor
- Hinda and Arthur Marcus Institute for Aging Research at Hebrew SeniorLife, Boston, MA, United States
- Department of Medicine, Harvard Medical School, Boston, MA, United States
| | - Alvaro Pascual-Leone
- Hinda and Arthur Marcus Institute for Aging Research at Hebrew SeniorLife, Boston, MA, United States
- Deanna and Sidney Wolk Center for Memory Health at Hebrew SeniorLife, Boston, MA, United States
- Department of Neurology, Harvard Medical School, Boston, MA, United States
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Wischnewski M, Alekseichuk I, Opitz A. Neurocognitive, physiological, and biophysical effects of transcranial alternating current stimulation. Trends Cogn Sci 2023; 27:189-205. [PMID: 36543610 PMCID: PMC9852081 DOI: 10.1016/j.tics.2022.11.013] [Citation(s) in RCA: 38] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 11/23/2022] [Accepted: 11/26/2022] [Indexed: 12/23/2022]
Abstract
Transcranial alternating current stimulation (tACS) can modulate human neural activity and behavior. Accordingly, tACS has vast potential for cognitive research and brain disorder therapies. The stimulation generates oscillating electric fields in the brain that can bias neural spike timing, causing changes in local neural oscillatory power and cross-frequency and cross-area coherence. tACS affects cognitive performance by modulating underlying single or nested brain rhythms, local or distal synchronization, and metabolic activity. Clinically, stimulation tailored to abnormal neural oscillations shows promising results in alleviating psychiatric and neurological symptoms. We summarize the findings of tACS mechanisms, its use for cognitive applications, and novel developments for personalized stimulation.
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Affiliation(s)
- Miles Wischnewski
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Ivan Alekseichuk
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA.
| | - Alexander Opitz
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA.
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Stock AK, Wendiggensen P, Ghin F, Beste C. Alcohol-induced deficits in reactive control of response selection and inhibition are counteracted by a seemingly paradox increase in proactive control. Sci Rep 2023; 13:1097. [PMID: 36658291 PMCID: PMC9852446 DOI: 10.1038/s41598-023-28012-5] [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: 01/15/2022] [Accepted: 01/11/2023] [Indexed: 01/20/2023] Open
Abstract
High-dose alcohol intoxication reduces cognitive control, including inhibition. Although inhibition deficits may contribute to the behavioral deficits commonly observed in alcohol use disorder (AUD), many questions about potentially modulating factors have remained unanswered. We examined the effects of experimentally induced high-dose alcohol intoxication (~ 1.1 ‰) on the interplay between controlled vs. automatic response selection and inhibition in healthy young men. A holistic EEG-based theta activity analysis that considered both reactive control during task performance and preceding proactive control processes was run. It revealed a previously unknown seesaw relationship, with decreased reactive control, but paradoxically increased proactive control. Most importantly, alcohol-induced increases in proactive occipital theta band power were associated with reductions in negative alcohol effects on reactive control processes associated with decreased activity in the SMA and medial frontal cortex. Our findings demonstrate that research should not solely focus on immediate effects during task performance. Aside from differential neurobiochemical and neuroanatomical effects of alcohol, it is also conceivable that proactive control may have been recruited in a (secondary) response to compensate for alcohol-induced impairments in reactive control. Against this background, it could be promising to investigate changes in such compensatory mechanisms in pronounced alcohol-associated inhibition deficits, like in AUD patients.
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Affiliation(s)
- Ann-Kathrin Stock
- Cognitive Neurophysiology, Department of Child and Adolescent Psychiatry, Faculty of Medicine of the TU Dresden, Schubertstrasse 42, 01309, Dresden, Germany. .,University Neuropsychology Center, Faculty of Medicine, TU Dresden, Dresden, Germany. .,Faculty of Psychology, TU Dresden, Dresden, Germany.
| | - Paul Wendiggensen
- Cognitive Neurophysiology, Department of Child and Adolescent Psychiatry, Faculty of Medicine of the TU Dresden, Schubertstrasse 42, 01309, Dresden, Germany.,University Neuropsychology Center, Faculty of Medicine, TU Dresden, Dresden, Germany
| | - Filippo Ghin
- Cognitive Neurophysiology, Department of Child and Adolescent Psychiatry, Faculty of Medicine of the TU Dresden, Schubertstrasse 42, 01309, Dresden, Germany.,University Neuropsychology Center, Faculty of Medicine, TU Dresden, Dresden, Germany
| | - Christian Beste
- Cognitive Neurophysiology, Department of Child and Adolescent Psychiatry, Faculty of Medicine of the TU Dresden, Schubertstrasse 42, 01309, Dresden, Germany.,University Neuropsychology Center, Faculty of Medicine, TU Dresden, Dresden, Germany
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Mosilhy EA, Alshial EE, Eltaras MM, Rahman MMA, Helmy HI, Elazoul AH, Hamdy O, Mohammed HS. Non-invasive transcranial brain modulation for neurological disorders treatment: A narrative review. Life Sci 2022; 307:120869. [DOI: 10.1016/j.lfs.2022.120869] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 08/01/2022] [Accepted: 08/03/2022] [Indexed: 11/30/2022]
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Antal A, Luber B, Brem AK, Bikson M, Brunoni AR, Cohen Kadosh R, Dubljević V, Fecteau S, Ferreri F, Flöel A, Hallett M, Hamilton RH, Herrmann CS, Lavidor M, Loo C, Lustenberger C, Machado S, Miniussi C, Moliadze V, Nitsche MA, Rossi S, Rossini PM, Santarnecchi E, Seeck M, Thut G, Turi Z, Ugawa Y, Venkatasubramanian G, Wenderoth N, Wexler A, Ziemann U, Paulus W. Non-invasive brain stimulation and neuroenhancement. Clin Neurophysiol Pract 2022; 7:146-165. [PMID: 35734582 PMCID: PMC9207555 DOI: 10.1016/j.cnp.2022.05.002] [Citation(s) in RCA: 56] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 04/19/2022] [Accepted: 05/18/2022] [Indexed: 12/15/2022] Open
Abstract
Attempts to enhance human memory and learning ability have a long tradition in science. This topic has recently gained substantial attention because of the increasing percentage of older individuals worldwide and the predicted rise of age-associated cognitive decline in brain functions. Transcranial brain stimulation methods, such as transcranial magnetic (TMS) and transcranial electric (tES) stimulation, have been extensively used in an effort to improve cognitive functions in humans. Here we summarize the available data on low-intensity tES for this purpose, in comparison to repetitive TMS and some pharmacological agents, such as caffeine and nicotine. There is no single area in the brain stimulation field in which only positive outcomes have been reported. For self-directed tES devices, how to restrict variability with regard to efficacy is an essential aspect of device design and function. As with any technique, reproducible outcomes depend on the equipment and how well this is matched to the experience and skill of the operator. For self-administered non-invasive brain stimulation, this requires device designs that rigorously incorporate human operator factors. The wide parameter space of non-invasive brain stimulation, including dose (e.g., duration, intensity (current density), number of repetitions), inclusion/exclusion (e.g., subject's age), and homeostatic effects, administration of tasks before and during stimulation, and, most importantly, placebo or nocebo effects, have to be taken into account. The outcomes of stimulation are expected to depend on these parameters and should be strictly controlled. The consensus among experts is that low-intensity tES is safe as long as tested and accepted protocols (including, for example, dose, inclusion/exclusion) are followed and devices are used which follow established engineering risk-management procedures. Devices and protocols that allow stimulation outside these parameters cannot claim to be "safe" where they are applying stimulation beyond that examined in published studies that also investigated potential side effects. Brain stimulation devices marketed for consumer use are distinct from medical devices because they do not make medical claims and are therefore not necessarily subject to the same level of regulation as medical devices (i.e., by government agencies tasked with regulating medical devices). Manufacturers must follow ethical and best practices in marketing tES stimulators, including not misleading users by referencing effects from human trials using devices and protocols not similar to theirs.
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Key Words
- AD, Alzheimer’s Disease
- BDNF, brain derived neurotrophic factor
- Cognitive enhancement
- DARPA, Defense Advanced Research Projects Agency
- DIY stimulation
- DIY, Do-It-Yourself
- DLPFC, dorsolateral prefrontal cortex
- EEG, electroencephalography
- EMG, electromyography
- FCC, Federal Communications Commission
- FDA, (U.S.) Food and Drug Administration
- Home-stimulation
- IFCN, International Federation of Clinical Neurophysiology
- LTD, long-term depression
- LTP, long-term potentiation
- MCI, mild cognitive impairment
- MDD, Medical Device Directive
- MDR, Medical Device Regulation
- MEP, motor evoked potential
- MRI, magnetic resonance imaging
- NIBS, noninvasive brain stimulation
- Neuroenhancement
- OTC, Over-The-Counter
- PAS, paired associative stimulation
- PET, positron emission tomography
- PPC, posterior parietal cortex
- QPS, quadripulse stimulation
- RMT, resting motor threshold
- SAE, serious adverse event
- SMA, supplementary motor cortex
- TBS, theta-burst stimulation
- TMS, transcranial magnetic stimulation
- Transcranial brain stimulation
- rTMS, repetitive transcranial magnetic stimulation
- tACS
- tACS, transcranial alternating current stimulation
- tDCS
- tDCS, transcranial direct current stimulation
- tES, transcranial electric stimulation
- tRNS, transcranial random noise stimulation
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Affiliation(s)
- Andrea Antal
- Department of Neurology, University Medical Center, Göttingen, Germany
| | - Bruce Luber
- Noninvasive Neuromodulation Unit, Experimental Therapeutics and Pathophysiology Branch, National Institute of Mental Health, Bethesda, MD, USA
| | - Anna-Katharine Brem
- University Hospital of Old Age Psychiatry, University of Bern, Bern, Switzerland
- Department of Old Age Psychiatry, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, United Kingdom
| | - Marom Bikson
- Biomedical Engineering at the City College of New York (CCNY) of the City University of New York (CUNY), NY, USA
| | - Andre R. Brunoni
- Departamento de Clínica Médica e de Psiquiatria, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
- Service of Interdisciplinary Neuromodulation (SIN), Laboratory of Neurosciences (LIM-27), Institute of Psychiatry, Hospital das Clínicas da Faculdade de Medicina da USP, São Paulo, Brazil
| | - Roi Cohen Kadosh
- School of Psychology, Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, UK
| | - Veljko Dubljević
- Science, Technology and Society Program, College of Humanities and Social Sciences, North Carolina State University, Raleigh, NC, USA
| | - Shirley Fecteau
- Department of Psychiatry and Neurosciences, Faculty of Medicine, Université Laval, CERVO Brain Research Centre, Centre intégré universitaire en santé et services sociaux de la Capitale-Nationale, Quebec City, Quebec, Canada
| | - Florinda Ferreri
- Unit of Neurology, Unit of Clinical Neurophysiology, Study Center of Neurodegeneration (CESNE), Department of Neuroscience, University of Padua, Padua, Italy
- Department of Clinical Neurophysiology, Kuopio University Hospital, University of Eastern Finland, Kuopio, Finland
| | - Agnes Flöel
- Department of Neurology, Universitätsmedizin Greifswald, 17475 Greifswald, Germany
- German Centre for Neurodegenerative Diseases (DZNE) Standort Greifswald, 17475 Greifswald, Germany
| | - Mark Hallett
- Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Roy H. Hamilton
- Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA
| | - Christoph S. Herrmann
- Experimental Psychology Lab, Department of Psychology, Carl von Ossietzky Universität, Oldenburg, Germany
| | - Michal Lavidor
- Department of Psychology and the Gonda Brain Research Center, Bar Ilan University, Israel
| | - Collen Loo
- School of Psychiatry and Black Dog Institute, University of New South Wales; The George Institute; Sydney, Australia
| | - Caroline Lustenberger
- Neural Control of Movement Lab, Institute of Human Movement Sciences and Sport, Department of Health Sciences and Technology, ETH Zurich, 8092 Zurich, Switzerland
| | - Sergio Machado
- Department of Sports Methods and Techniques, Federal University of Santa Maria, Santa Maria, Brazil
- Laboratory of Physical Activity Neuroscience, Neurodiversity Institute, Queimados-RJ, Brazil
| | - Carlo Miniussi
- Center for Mind/Brain Sciences – CIMeC and Centre for Medical Sciences - CISMed, University of Trento, Rovereto, Italy
| | - Vera Moliadze
- Institute of Medical Psychology and Medical Sociology, University Medical Center Schleswig Holstein, Kiel University, Kiel, Germany
| | - Michael A Nitsche
- Department Psychology and Neurosciences, Leibniz Research Centre for Working Environment and Human Factors at TU, Dortmund, Germany
- Dept. Neurology, University Medical Hospital Bergmannsheil, Bochum, Germany
| | - Simone Rossi
- Siena Brain Investigation and Neuromodulation Lab (Si-BIN Lab), Unit of Neurology and Clinical Neurophysiology, Department of Medicine, Surgery and Neuroscience, University of Siena, Italy
| | - Paolo M. Rossini
- Department of Neuroscience and Neurorehabilitation, Brain Connectivity Lab, IRCCS-San Raffaele-Pisana, Rome, Italy
| | - Emiliano Santarnecchi
- Precision Neuroscience and Neuromodulation Program, Gordon Center for Medical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Margitta Seeck
- Department of Clinical Neurosciences, Hôpitaux Universitaires de Genève, Switzerland
| | - Gregor Thut
- Centre for Cognitive Neuroimaging, School of Psychology and Neuroscience, EEG & Epolepsy Unit, University of Glasgow, United Kingdom
| | - Zsolt Turi
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Yoshikazu Ugawa
- Department of Human Neurophysiology, Fukushima Medical University, Fukushima, Japan
| | | | - Nicole Wenderoth
- Neural Control of Movement Lab, Institute of Human Movement Sciences and Sport, Department of Health Sciences and Technology, ETH Zurich, 8092 Zurich, Switzerland
- Future Health Technologies, Singapore-ETH Centre, Campus for Research Excellence And Technological Enterprise (CREATE), Singapore
| | - Anna Wexler
- Department of Medical Ethics and Health Policy, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Ulf Ziemann
- Department of Neurology and Stroke, University of Tübingen, Germany
- Hertie Institute for Clinical Brain Research, University of Tübingen, Germany
| | - Walter Paulus
- Department of of Neurology, Ludwig Maximilians University Munich, Germany
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Muffel T, Shih PC, Kalloch B, Nikulin V, Villringer A, Sehm B. Differential effects of anodal and dual tDCS on sensorimotor functions in chronic hemiparetic stroke patients. Brain Stimul 2022; 15:509-522. [DOI: 10.1016/j.brs.2022.02.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 02/14/2022] [Accepted: 02/21/2022] [Indexed: 11/24/2022] Open
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Ghin F, Beste C, Stock AK. Neurobiological mechanisms of control in alcohol use disorder - moving towards mechanism-based non-invasive brain stimulation treatments. Neurosci Biobehav Rev 2021; 133:104508. [PMID: 34942268 DOI: 10.1016/j.neubiorev.2021.12.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 12/14/2021] [Accepted: 12/19/2021] [Indexed: 12/13/2022]
Abstract
Alcohol use disorder (AUD) is characterized by excessive habitual drinking and loss of control over alcohol intake despite negative consequences. Both of these aspects foster uncontrolled drinking and high relapse rates in AUD patients. Yet, common interventions mostly focus on the phenomenological level, and prioritize the reduction of craving and withdrawal symptoms. Our review provides a mechanistic understanding of AUD and suggests alternative therapeutic approaches targeting the mechanisms underlying dysfunctional alcohol-related behaviours. Specifically, we explain how repeated drinking fosters the development of rigid drinking habits and is associated with diminished cognitive control. These behavioural and cognitive effects are then functionally related to the neurobiochemical effects of alcohol abuse. We further explain how alterations in fronto-striatal network activity may constitute the neurobiological correlates of these alcohol-related dysfunctions. Finally, we discuss limitations in current pharmacological AUD therapies and suggest non-invasive brain stimulation (like TMS and tDCS interventions) as a potential addition/alternative for modulating the activation of both cortical and subcortical areas to help re-establish the functional balance between controlled and automatic behaviour.
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Affiliation(s)
- Filippo Ghin
- Cognitive Neurophysiology, Department of Child and Adolescent Psychiatry, Faculty of Medicine, TU Dresden, Germany; University Neuropsychology Center, Faculty of Medicine, TU Dresden, Germany
| | - Christian Beste
- Cognitive Neurophysiology, Department of Child and Adolescent Psychiatry, Faculty of Medicine, TU Dresden, Germany; University Neuropsychology Center, Faculty of Medicine, TU Dresden, Germany
| | - Ann-Kathrin Stock
- Cognitive Neurophysiology, Department of Child and Adolescent Psychiatry, Faculty of Medicine, TU Dresden, Germany; University Neuropsychology Center, Faculty of Medicine, TU Dresden, Germany; Biopsychology, Faculty of Psychology, TU Dresden, Dresden, Germany.
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12
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Behavioral and electrocortical effects of transcranial alternating current stimulation during advice-guided decision-making. NEUROIMAGE: REPORTS 2021. [DOI: 10.1016/j.ynirp.2021.100052] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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13
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Schmied A, Varma S, Dubinsky JM. Acceptability of Neuroscientific Interventions in Education. SCIENCE AND ENGINEERING ETHICS 2021; 27:52. [PMID: 34351520 DOI: 10.1007/s11948-021-00328-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 07/06/2021] [Indexed: 06/13/2023]
Abstract
Researchers are increasingly applying neuroscience technologies that probe or manipulate the brain to improve educational outcomes. However, their use remains fraught with ethical controversies. Here, we investigate the acceptability of neuroscience applications to educational practice in two groups of young adults: those studying bioscience who will be driving future basic neuroscience research and technology transfer, and those studying education who will be choosing among neuroscience-derived applications for their students. Respondents rated the acceptability of six scenarios describing neuroscience applications to education spanning multiple methodologies, from neuroimaging to neuroactive drugs to brain stimulation. They did so from two perspectives (student, teacher) and for three recipient populations (low-achieving, high-achieving students, students with learning disabilities). Overall, the biosciences students were more favorable to all neuroscience applications than the education students. Scenarios that measured brain activity (i.e., EEG or fMRI) to assess or predict intellectual abilities were deemed more acceptable than manipulations of mental activity by drug use or stimulation techniques, which may violate body integrity. Enhancement up to the norm for low-achieving students and especially students with learning disabilities was more favorably viewed than enhancement beyond the norm for high-achieving students. Finally, respondents rated neuroscientific applications to be less acceptable when adopting the perspective of a teacher than that of a student. Future studies should go beyond the acceptability ratings collected here to delineate the role that concepts of access, equity, authenticity, agency and personal choice play in guiding respondents' reasoning.
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Affiliation(s)
- A Schmied
- Department of Educational Psychology, University of Minnesota, Minneapolis, MN, USA
| | - S Varma
- School of Interactive Computing, College of Computing & School of Psychology, College of Sciences, Georgia Institute of Technology, Atlanta, GA, USA
| | - J M Dubinsky
- Department of Neuroscience, University of Minnesota, 6-145 Jackson Hall, 321 Church St SE, Minneapolis, MN, 55455, USA.
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Goering S, Klein E, Specker Sullivan L, Wexler A, Agüera y Arcas B, Bi G, Carmena JM, Fins JJ, Friesen P, Gallant J, Huggins JE, Kellmeyer P, Marblestone A, Mitchell C, Parens E, Pham M, Rubel A, Sadato N, Teicher M, Wasserman D, Whittaker M, Wolpaw J, Yuste R. Recommendations for Responsible Development and Application of Neurotechnologies. NEUROETHICS-NETH 2021; 14:365-386. [PMID: 33942016 PMCID: PMC8081770 DOI: 10.1007/s12152-021-09468-6] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 04/15/2021] [Indexed: 12/12/2022]
Abstract
Advancements in novel neurotechnologies, such as brain computer interfaces (BCI) and neuromodulatory devices such as deep brain stimulators (DBS), will have profound implications for society and human rights. While these technologies are improving the diagnosis and treatment of mental and neurological diseases, they can also alter individual agency and estrange those using neurotechnologies from their sense of self, challenging basic notions of what it means to be human. As an international coalition of interdisciplinary scholars and practitioners, we examine these challenges and make recommendations to mitigate negative consequences that could arise from the unregulated development or application of novel neurotechnologies. We explore potential ethical challenges in four key areas: identity and agency, privacy, bias, and enhancement. To address them, we propose (1) democratic and inclusive summits to establish globally-coordinated ethical and societal guidelines for neurotechnology development and application, (2) new measures, including "Neurorights," for data privacy, security, and consent to empower neurotechnology users' control over their data, (3) new methods of identifying and preventing bias, and (4) the adoption of public guidelines for safe and equitable distribution of neurotechnological devices.
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Affiliation(s)
| | - Eran Klein
- University of Washington, Seattle, WA USA
- Oregon Health & Science University, Portland, OR USA
| | | | - Anna Wexler
- University of Pennsylvania, Philadelphia, PA USA
| | | | - Guoqiang Bi
- University of Science and Technology of China, Hefei, China
- CAS Shenzhen Institute of Advanced Technology, Shenzhen, China
| | | | | | | | | | | | | | | | | | - Erik Parens
- The Hastings Center, Philipstown, Garrison, NY USA
| | | | - Alan Rubel
- University of Wisconsin-Madison, Madison, WI USA
| | - Norihiro Sadato
- National Institute for Physiological Sciences, Okazaki, Aichi Japan
| | | | | | - Meredith Whittaker
- Google, Mountain View, CA USA
- AI Now, New York City, NY USA
- New York University, New York City, NY USA
| | - Jonathan Wolpaw
- National Center for Adaptive Neurotechnologies, Albany, NY USA
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15
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Luckhardt C, Schütz M, Mühlherr A, Mössinger H, Boxhoorn S, Dempfle A, Salvador R, Ruffini G, Pereira HC, Castelo-Branco M, Latinus M, Bonnet-Brilhault F, Siemann J, Siniatchkin M, Ecker C, Freitag CM. Phase-IIa randomized, double-blind, sham-controlled, parallel group trial on anodal transcranial direct current stimulation (tDCS) over the left and right tempo-parietal junction in autism spectrum disorder-StimAT: study protocol for a clinical trial. Trials 2021; 22:248. [PMID: 33823927 PMCID: PMC8025356 DOI: 10.1186/s13063-021-05172-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 03/06/2021] [Indexed: 01/01/2023] Open
Abstract
Background Autism spectrum disorder (ASD) is characterized by impaired social communication and interaction, and stereotyped, repetitive behaviour and sensory interests. To date, there is no effective medication that can improve social communication and interaction in ASD, and effect sizes of behaviour-based psychotherapy remain in the low to medium range. Consequently, there is a clear need for new treatment options. ASD is associated with altered activation and connectivity patterns in brain areas which process social information. Transcranial direct current stimulation (tDCS) is a technique that applies a weak electrical current to the brain in order to modulate neural excitability and alter connectivity. Combined with specific cognitive tasks, it allows to facilitate and consolidate the respective training effects. Therefore, application of tDCS in brain areas relevant to social cognition in combination with a specific cognitive training is a promising treatment approach for ASD. Methods A phase-IIa pilot randomized, double-blind, sham-controlled, parallel-group clinical study is presented, which aims at investigating if 10 days of 20-min multi-channel tDCS stimulation of the bilateral tempo-parietal junction (TPJ) at 2.0 mA in combination with a computer-based cognitive training on perspective taking, intention and emotion understanding, can improve social cognitive abilities in children and adolescents with ASD. The main objectives are to describe the change in parent-rated social responsiveness from baseline (within 1 week before first stimulation) to post-intervention (within 7 days after last stimulation) and to monitor safety and tolerability of the intervention. Secondary objectives include the evaluation of change in parent-rated social responsiveness at follow-up (4 weeks after end of intervention), change in other ASD core symptoms and psychopathology, social cognitive abilities and neural functioning post-intervention and at follow-up in order to explore underlying neural and cognitive mechanisms. Discussion If shown, positive results regarding change in parent-rated social cognition and favourable safety and tolerability of the intervention will confirm tDCS as a promising treatment for ASD core-symptoms. This may be a first step in establishing a new and cost-efficient intervention for individuals with ASD. Trial registration The trial is registered with the German Clinical Trials Register (DRKS), DRKS00014732. Registered on 15 August 2018. Protocol version This study protocol refers to protocol version 1.2 from 24 May 2019. Supplementary Information The online version contains supplementary material available at 10.1186/s13063-021-05172-1.
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Affiliation(s)
- Christina Luckhardt
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Frankfurt, Goethe University, Deutschordenstr.50, 60528, Frankfurt, Germany.
| | - Magdalena Schütz
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Frankfurt, Goethe University, Deutschordenstr.50, 60528, Frankfurt, Germany
| | - Andreas Mühlherr
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Frankfurt, Goethe University, Deutschordenstr.50, 60528, Frankfurt, Germany
| | - Hannah Mössinger
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Frankfurt, Goethe University, Deutschordenstr.50, 60528, Frankfurt, Germany
| | - Sara Boxhoorn
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Frankfurt, Goethe University, Deutschordenstr.50, 60528, Frankfurt, Germany
| | - Astrid Dempfle
- Institute of Medical Informatics and Statistics (IMIS), Kiel University, Brunswiker Str. 10, 24105, Kiel, Germany
| | - Ricardo Salvador
- Neuroelectrics SLU, Av. Tibidabo 47 Bis, 08035, Barcelona, Spain
| | - Giulio Ruffini
- Neuroelectrics SLU, Av. Tibidabo 47 Bis, 08035, Barcelona, Spain
| | - Helena C Pereira
- Coimbra Institute for Biomedical Imaging and Translational Research (CIBIT), ICNAS, Faculty of Medicine, Academic Clinical Centre, University of Coimbra (UC), Paco das Escolas, 3001 451, Coimbra, Portugal
| | - Miguel Castelo-Branco
- Coimbra Institute for Biomedical Imaging and Translational Research (CIBIT), ICNAS, Faculty of Medicine, Academic Clinical Centre, University of Coimbra (UC), Paco das Escolas, 3001 451, Coimbra, Portugal
| | - Marianne Latinus
- UMR 1253, iBrain, Université de Tours, Inserm, Centre de Pédopsychiatrie, CHRU Bretonneau, 2 bd Tonnellé, 37044, Tours Cedex 9, France
| | - Frédérique Bonnet-Brilhault
- UMR 1253, iBrain, Université de Tours, Inserm, Centre de Pédopsychiatrie, CHRU Bretonneau, 2 bd Tonnellé, 37044, Tours Cedex 9, France.,Centre Hospitalier Universitaire de Tours (CHUT), Centre Universitaire de Pédopsychiatrie, UMR930 INSERM / Equipe autism, CHRU Tours / Hôpital Bretonneau, 2 Bd Tonnellé, 37044, Tours Cedex 9, France
| | - Julia Siemann
- Clinic of Child and Adolescent Psychiatry and Psychotherapy, Protestant Hospital Bethel, EvKB, Remterweg 13a, 33617, Bielefeld, Germany
| | - Michael Siniatchkin
- Clinic of Child and Adolescent Psychiatry and Psychotherapy, Protestant Hospital Bethel, EvKB, Remterweg 13a, 33617, Bielefeld, Germany
| | - Christine Ecker
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Frankfurt, Goethe University, Deutschordenstr.50, 60528, Frankfurt, Germany
| | - Christine M Freitag
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Frankfurt, Goethe University, Deutschordenstr.50, 60528, Frankfurt, Germany
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16
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Brambilla M, Dinkelbach L, Bigler A, Williams J, Zokaei N, Cohen Kadosh R, Brem AK. The Effect of Transcranial Random Noise Stimulation on Cognitive Training Outcome in Healthy Aging. Front Neurol 2021; 12:625359. [PMID: 33767658 PMCID: PMC7985554 DOI: 10.3389/fneur.2021.625359] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 02/09/2021] [Indexed: 12/20/2022] Open
Abstract
Background and Objective: Aging is associated with a decline in attentional and executive abilities, which are linked to physiological, structural, and functional brain changes. A variety of novel non-invasive brain stimulation methods have been probed in terms of their neuroenhancement efficacy in the last decade; one that holds significant promise is transcranial random noise stimulation (tRNS) that delivers an alternate current at random amplitude and frequency. The aim of this study was to investigate whether repeated sessions of tRNS applied as an add-on to cognitive training (CT) may induce long-term near and far transfer cognitive improvements. Methods: In this sham-controlled, randomized, double-blinded study forty-two older adults (age range 60-86 years) were randomly assigned to one of three intervention groups that received 20 min of 0.705 mA tRNS (N = 14), 1 mA tRNS (N = 14), or sham tRNS (N = 19) combined with 30 min of CT of executive functions (cognitive flexibility, inhibitory control, working memory). tRNS was applied bilaterally over the dorsolateral prefrontal cortices for five sessions. The primary outcome (non-verbal logical reasoning) and other cognitive functions (attention, memory, executive functions) were assessed before and after the intervention and at a 1-month follow-up. Results: Non-verbal logical reasoning, inhibitory control and reaction time improved significantly over time, but stimulation did not differentially affect this improvement. These changes occurred during CT, while no further improvement was observed during follow-up. Performance change in logical reasoning was significantly correlated with age in the group receiving 1 mA tRNS, indicating that older participants profited more from tRNS than younger participants. Performance change in non-verbal working memory was significantly correlated with age in the group receiving sham tRNS, indicating that in contrast to active tRNS, older participants in the sham group declined more than younger participants. Interpretation: CT induced cognitive improvements in all treatment groups, but tRNS did not modulate most of these cognitive improvements. However, the effect of tRNS depended on age in some cognitive functions. We discuss possible explanations leading to this result that can help to improve the design of future neuroenhancement studies in older populations.
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Affiliation(s)
- Michela Brambilla
- Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom
- Biomedical and Clinical Sciences Department, Center for Research and Treatment on Cognitive Dysfunctions, “Luigi Sacco” Hospital, University of Milan, Milan, Italy
| | - Lars Dinkelbach
- Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom
- Department of Neurology, Institute of Clinical Neuroscience and Medical Psychology, Heinrich Heine University, Duesseldorf, Germany
| | - Annelien Bigler
- Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom
- Department of Experimental Psychology, Ghent University, Ghent, Belgium
| | - Joseph Williams
- Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom
- Medical Sciences Division, University of Oxford, Oxford, United Kingdom
| | - Nahid Zokaei
- Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom
| | - Roi Cohen Kadosh
- Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom
| | - Anna-Katharine Brem
- Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom
- Department of Neurology, Berenson-Allen Center for Noninvasive Brain Stimulation and Division for Cognitive Neurology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, United States
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17
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Online and offline effects of transcranial alternating current stimulation of the primary motor cortex. Sci Rep 2021; 11:3854. [PMID: 33594133 PMCID: PMC7887242 DOI: 10.1038/s41598-021-83449-w] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 01/05/2021] [Indexed: 01/31/2023] Open
Abstract
Transcranial alternating current stimulation (tACS) is a non-invasive brain stimulation technique that allows interaction with endogenous cortical oscillatory rhythms by means of external sinusoidal potentials. The physiological mechanisms underlying tACS effects are still under debate. Whereas online (e.g., ongoing) tACS over the motor cortex induces robust state-, phase- and frequency-dependent effects on cortical excitability, the offline effects (i.e. after-effects) of tACS are less clear. Here, we explored online and offline effects of tACS in two single-blind, sham-controlled experiments. In both experiments we used neuronavigated transcranial magnetic stimulation (TMS) of the primary motor cortex (M1) as a probe to index changes of cortical excitability and delivered M1 tACS at 10 Hz (alpha), 20 Hz (beta) and sham (30 s of low-frequency transcranial random noise stimulation; tRNS). Corticospinal excitability was measured by single pulse TMS-induced motor evoked potentials (MEPs). tACS was delivered online in Experiment 1 and offline in Experiment 2. In Experiment 1, the increase of MEPs size was maximal with the 20 Hz stimulation, however in Experiment 2 neither the 10 Hz nor the 20 Hz stimulation induced tACS offline effects. These findings support the idea that tACS affects cortical excitability only during online application, at least when delivered on the scalp overlying M1, thereby contributing to the development of effective protocols that can be applied to clinical populations.
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18
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Brunyé TT, Patterson JE, Wooten T, Hussey EK. A Critical Review of Cranial Electrotherapy Stimulation for Neuromodulation in Clinical and Non-clinical Samples. Front Hum Neurosci 2021; 15:625321. [PMID: 33597854 PMCID: PMC7882621 DOI: 10.3389/fnhum.2021.625321] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 01/07/2021] [Indexed: 01/27/2023] Open
Abstract
Cranial electrotherapy stimulation (CES) is a neuromodulation tool used for treating several clinical disorders, including insomnia, anxiety, and depression. More recently, a limited number of studies have examined CES for altering affect, physiology, and behavior in healthy, non-clinical samples. The physiological, neurochemical, and metabolic mechanisms underlying CES effects are currently unknown. Computational modeling suggests that electrical current administered with CES at the earlobes can reach cortical and subcortical regions at very low intensities associated with subthreshold neuromodulatory effects, and studies using electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) show some effects on alpha band EEG activity, and modulation of the default mode network during CES administration. One theory suggests that CES modulates brain stem (e.g., medulla), limbic (e.g., thalamus, amygdala), and cortical (e.g., prefrontal cortex) regions and increases relative parasympathetic to sympathetic drive in the autonomic nervous system. There is no direct evidence supporting this theory, but one of its assumptions is that CES may induce its effects by stimulating afferent projections of the vagus nerve, which provides parasympathetic signals to the cardiorespiratory and digestive systems. In our critical review of studies using CES in clinical and non-clinical populations, we found severe methodological concerns, including potential conflicts of interest, risk of methodological and analytic biases, issues with sham credibility, lack of blinding, and a severe heterogeneity of CES parameters selected and employed across scientists, laboratories, institutions, and studies. These limitations make it difficult to derive consistent or compelling insights from the extant literature, tempering enthusiasm for CES and its potential to alter nervous system activity or behavior in meaningful or reliable ways. The lack of compelling evidence also motivates well-designed and relatively high-powered experiments to assess how CES might modulate the physiological, affective, and cognitive responses to stress. Establishing reliable empirical links between CES administration and human performance is critical for supporting its prospective use during occupational training, operations, or recovery, ensuring reliability and robustness of effects, characterizing if, when, and in whom such effects might arise, and ensuring that any benefits of CES outweigh the risks of adverse events.
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Affiliation(s)
- Tad T. Brunyé
- U. S. Army Combat Capabilities Development Command Soldier Center, Cognitive Science Team, Natick, MA, United States
- Center for Applied Brain and Cognitive Sciences, Tufts University, Medford, MA, United States
| | - Joseph E. Patterson
- Center for Applied Brain and Cognitive Sciences, Tufts University, Medford, MA, United States
| | - Thomas Wooten
- Department of Psychology, Tufts University, Medford, MA, United States
| | - Erika K. Hussey
- U. S. Army Combat Capabilities Development Command Soldier Center, Cognitive Science Team, Natick, MA, United States
- Center for Applied Brain and Cognitive Sciences, Tufts University, Medford, MA, United States
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19
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Perez FP, Maloney B, Chopra N, Morisaki JJ, Lahiri DK. Repeated electromagnetic field stimulation lowers amyloid-β peptide levels in primary human mixed brain tissue cultures. Sci Rep 2021; 11:621. [PMID: 33436686 PMCID: PMC7804462 DOI: 10.1038/s41598-020-77808-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 11/17/2020] [Indexed: 02/07/2023] Open
Abstract
Late Onset Alzheimer's Disease is the most common cause of dementia, characterized by extracellular deposition of plaques primarily of amyloid-β (Aβ) peptide and tangles primarily of hyperphosphorylated tau protein. We present data to suggest a noninvasive strategy to decrease potentially toxic Aβ levels, using repeated electromagnetic field stimulation (REMFS) in primary human brain (PHB) cultures. We examined effects of REMFS on Aβ levels (Aβ40 and Aβ42, that are 40 or 42 amino acid residues in length, respectively) in PHB cultures at different frequencies, powers, and specific absorption rates (SAR). PHB cultures at day in vitro 7 (DIV7) treated with 64 MHz, and 1 hour daily for 14 days (DIV 21) had significantly reduced levels of secreted Aβ40 (p = 001) and Aβ42 (p = 0.029) peptides, compared to untreated cultures. PHB cultures (DIV7) treated at 64 MHz, for 1 or 2 hour during 14 days also produced significantly lower Aβ levels. PHB cultures (DIV28) treated with 64 MHz 1 hour/day during 4 or 8 days produced a similar significant reduction in Aβ40 levels. 0.4 W/kg was the minimum SAR required to produce a biological effect. Exposure did not result in cellular toxicity nor significant changes in secreted Aβ precursor protein-α (sAPPα) levels, suggesting the decrease in Aβ did not likely result from redirection toward the α-secretase pathway. EMF frequency and power used in our work is utilized in human magnetic resonance imaging (MRI, thus suggesting REMFS can be further developed in clinical settings to modulate Aβ deposition.
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Affiliation(s)
- Felipe P Perez
- Indiana University School of Medicine, Indianapolis, IN, USA
- Department of Medicine, Division of General Internal Medicine and Geriatrics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Bryan Maloney
- Indiana University School of Medicine, Indianapolis, IN, USA
- Department of Psychiatry, Institute of Psychiatric Research, Neuroscience Research Center, Indiana University School of Medicine, 320 W. 15th St, Indianapolis, IN, 46201, USA
| | - Nipun Chopra
- Indiana University School of Medicine, Indianapolis, IN, USA
- Department of Psychiatry, Institute of Psychiatric Research, Neuroscience Research Center, Indiana University School of Medicine, 320 W. 15th St, Indianapolis, IN, 46201, USA
| | - Jorge J Morisaki
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA
| | - Debomoy K Lahiri
- Indiana University School of Medicine, Indianapolis, IN, USA.
- Department of Psychiatry, Institute of Psychiatric Research, Neuroscience Research Center, Indiana University School of Medicine, 320 W. 15th St, Indianapolis, IN, 46201, USA.
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA.
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20
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Memon AM. Transcranial Magnetic Stimulation in Treatment of Adolescent Attention Deficit/Hyperactivity Disorder: A Narrative Review of Literature. INNOVATIONS IN CLINICAL NEUROSCIENCE 2021; 18:43-46. [PMID: 34150364 PMCID: PMC8195561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Attention deficit/hyperactivity disorder (ADHD), one of the most common neurodevelopmental disorders, affected 3.3 million adolescents in the United States (US) in 2016. Ten to 30 percent of these patients do not respond to standard pharmacotherapy and, as a result, suffer adverse physical/mental health and socioeconomic consequences. Despite being approved by the US Food and Drug Administration (FDA) for treatment of adult depression, with evidence suggesting positive outcomes in children and adults in treatment of ADHD and good safety and tolerability records, there is no existent literature reviewing the efficacy, safety, and feasibility of use of transcranial magnetic stimulation (TMS) in the treatment of adolescent ADHD. Thus, We have conducted this review for which a thorough literature search was conducted on PubMed and PsycInfo databases using a combination of MeSH terms that yielded 32 articles, five of which satisfied the inclusion criteria. We observed objective improvements in ADHD treatment outcomes in adolescent patients who participated in a randomized, sham-controlled, crossover pilot study that assessed the safety and efficacy of TMS. The study participants did not suffer any major adverse events, which was also supported by findings from other studies. However, since only one study out of five included in the review is an interventional study with limited number of study participants, there is a need to conduct large-scale clinical trials that recruit a greater number of study participants to explore the clinical efficacy and safety of TMS in the treatment of adolescent ADHD patients who do not respond to or tolerate standard pharmacotherapy based on the preliminary data extracted to this end.
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Affiliation(s)
- Aksha M Memon
- Dr. Memon is an Assistant Professor with the Department of Foundational Medical Studies at Oakland University William Beaumont School of Medicine in Rochester Hills, Michigan
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21
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Santos FH, Mosbacher JA, Menghini D, Rubia K, Grabner RH, Cohen Kadosh R. Effects of transcranial stimulation in developmental neurocognitive disorders: A critical appraisal. PROGRESS IN BRAIN RESEARCH 2021; 264:1-40. [PMID: 34167652 DOI: 10.1016/bs.pbr.2021.01.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Non-invasive brain stimulation (NIBS) has been highlighted as a powerful tool to promote neuroplasticity, and an attractive approach to support cognitive remediation. Here we provide a systematic review of 26 papers using NIBS to ameliorate cognitive dysfunctions in three prevalent neurodevelopmental disorders: Attention-Deficit/Hyperactivity Disorder (ADHD), Developmental Dyslexia and Developmental Dyscalculia. An overview of the state of research shows a predominance of studies using repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) techniques, and an unequal distribution among clinical conditions. Regarding the utility of NIBS, the results are promising but also ambiguous. Twenty-three papers reported beneficial effects, but many of these effects were found only once or were only partially replicated and some studies even reported detrimental effects. Furthermore, most studies differed in at least one core aspect, the NIBS applied, the questionnaires and cognitive tests conducted, or the age group investigated, and sample sizes were mostly small. Hence, further studies are needed to rigorously examine the potential of NIBS in the remediation of cognitive functions. Finally, we discuss potential caveats and future directions. We reason that if adequately addressing these challenges NIBS can be feasible, with potential benefits in treating neurodevelopmental disorders.
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Affiliation(s)
- Flavia H Santos
- School of Psychology, University College Dublin, Dublin, Ireland
| | - Jochen A Mosbacher
- Educational Neuroscience, Institute of Psychology, University of Graz, Graz, Austria.
| | - Deny Menghini
- Department of Neuroscience, Ospedale Pediatrico Bambino Gesù, Rome, Italy
| | - Katya Rubia
- Department of Child & Adolescent Psychiatry, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Roland H Grabner
- Educational Neuroscience, Institute of Psychology, University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Roi Cohen Kadosh
- Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom
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22
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Westwood SJ, Radua J, Rubia K. Noninvasive brain stimulation in children and adults with attention-deficit/hyperactivity disorder: a systematic review and meta-analysis. J Psychiatry Neurosci 2021; 46:E14-E33. [PMID: 33009906 PMCID: PMC7955851 DOI: 10.1503/jpn.190179] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Repetitive transcranial magnetic stimulation (rTMS) or transcranial direct current stimulation (tDCS) could provide treatment alternatives to stimulant medication for attention-deficit/hyperactivity disorder (ADHD), given some evidence for improvements in cognition and clinical symptoms. However, despite a lack of solid evidence for their use, rTMS and tDCS are already offered clinically and commercially in ADHD. This systematic review and meta-analysis aimed to critically appraise rTMS and tDCS studies in ADHD to inform good research and clinical practice. METHODS A systematic search (up to February 2019) identified 18 studies (rTMS 4, tDCS 14; 311 children and adults with ADHD) stimulating mainly the dorsolateral prefrontal cortex (dlPFC). We included 12 anodal tDCS studies (232 children and adults with ADHD) in 3 random-effects meta-analyses of cognitive measures of attention, inhibition and processing speed. RESULTS The review of rTMS and tDCS showed positive effects in some functions but not others, and little evidence for clinical improvement. The meta-analyses of 1 to 5 sessions of anodal tDCS over mainly the left or bilateral dlPFC showed trend-level improvements in inhibition and processing speed, but not in attention. LIMITATIONS Heterogeneity in stimulation parameters, patient age and outcome measures limited the interpretation of findings. CONCLUSION The review and meta-analysis showed limited evidence that 1 to 5 sessions of rTMS and tDCS, mostly of the dlPFC, improved clinical or cognitive measures of ADHD. These findings did not support using rTMS or tDCS of the dlPFC as an alternative neurotherapy for ADHD as yet. Larger, multi-session stimulation studies identifying more optimal sites and stimulation parameters in combination with cognitive training could achieve larger effects.
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Affiliation(s)
- Samuel J Westwood
- From the Department of Child & Adolescent Psychiatry, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom (Westwood, Rubia); the Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain (Radua); the Mental Health Research Networking Centre (CIBERSAM), Madrid, Spain (Radua); the Department of Clinical Neuroscience, Centre for Psychiatric Research and Education, Karolinska Institutet, Tomtebodavägen 18A, Stockholm, Sweden (Radua); and the Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, London, United Kingdom (Radua)
| | - Joaquim Radua
- From the Department of Child & Adolescent Psychiatry, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom (Westwood, Rubia); the Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain (Radua); the Mental Health Research Networking Centre (CIBERSAM), Madrid, Spain (Radua); the Department of Clinical Neuroscience, Centre for Psychiatric Research and Education, Karolinska Institutet, Tomtebodavägen 18A, Stockholm, Sweden (Radua); and the Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, London, United Kingdom (Radua)
| | - Katya Rubia
- From the Department of Child & Adolescent Psychiatry, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom (Westwood, Rubia); the Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain (Radua); the Mental Health Research Networking Centre (CIBERSAM), Madrid, Spain (Radua); the Department of Clinical Neuroscience, Centre for Psychiatric Research and Education, Karolinska Institutet, Tomtebodavägen 18A, Stockholm, Sweden (Radua); and the Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, London, United Kingdom (Radua)
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Abstract
Cognitive enhancement is becoming progressively popular as a subject of scientific investigation and by the public, although possible adverse effects are not sufficiently understood. We call for cognitive enhancement to build on more specific, mechanistic theories given that a-theoretical approaches to cognitive enhancement are both a cause and a consequence of a strong, if not exclusive focus on the benefits of procedures suited to enhance human cognition. We focus on downsides of cognitive enhancement and suggest that every attempt to enhance human cognition needs to deal with two basic principles: the neuro-competition principle and the nonlinearity principle. We discuss the possibility of both principles in light of recent attempts to improve human cognition by means of transcranial direct current stimulation, a well-established brain stimulation method, and clinically relevant nootropic drugs. We propose that much stronger emphasis on mechanistic theorizing is necessary in guiding future research on both the upsides and the downsides of cognitive enhancement.
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Affiliation(s)
- Lorenza S Colzato
- Cognitive Neurophysiology, Department of Child and Adolescent Psychiatry, Faculty of Medicine, TU Dresden, Dresden, Germany.,Department of Cognitive Psychology, Institute of Cognitive Neuroscience, Faculty of Psychology, Ruhr University Bochum, Bochum, Germany.,Cognitive Psychology, Faculty of Psychology, Shandong Normal University, Jinan, China
| | - Bernhard Hommel
- Cognitive Psychology, Faculty of Psychology, Shandong Normal University, Jinan, China.,Cognitive Psychology Unit & Leiden Institute for Brain and Cognition, Leiden University, Leiden, Netherlands
| | - Christian Beste
- Cognitive Neurophysiology, Department of Child and Adolescent Psychiatry, Faculty of Medicine, TU Dresden, Dresden, Germany.,Cognitive Psychology, Faculty of Psychology, Shandong Normal University, Jinan, China
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24
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Perceval G, Martin AK, Copland DA, Laine M, Meinzer M. Multisession transcranial direct current stimulation facilitates verbal learning and memory consolidation in young and older adults. BRAIN AND LANGUAGE 2020; 205:104788. [PMID: 32199339 DOI: 10.1016/j.bandl.2020.104788] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 01/27/2020] [Accepted: 03/05/2020] [Indexed: 06/10/2023]
Abstract
This study investigated effects of multisession transcranial direct-current stimulation on learning and maintenance of novel memory content and scrutinised effects of baseline cognitive status and the role of multi-session tDCS on overnight memory consolidation. In a prospective, randomized, double-blind, parallel-group, sham-tDCS controlled design, 101 healthy young and older adults completed a five-day verbal associative learning paradigm while receiving multisession tDCS to the task-relevant left prefrontal cortex. In older adults, active multisession tDCS enhanced recall performance after each daily training session. Effects were maintained the next morning and during follow-up assessments (one week; three months). In young adults, multisession tDCS significantly increased long-term recall. Unlike previous findings in the motor domain, beneficial effects of multisession tDCS on cognitive learning and memory were notexclusively due to enhanced memory consolidation. Positive stimulation effects were primarily found in participants with lower baseline learning ability, suggesting that multisession tDCS may counteract memory impairment in health and disease.
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Affiliation(s)
- Garon Perceval
- The University of Queensland, Centre for Clinical Research, Brisbane, Australia; Department of Psychology, School of Education, Soochow University, Suzhou, China
| | - Andrew K Martin
- The University of Queensland, Centre for Clinical Research, Brisbane, Australia; University of Kent, Department of Psychology, Canterbury, UK
| | - David A Copland
- The University of Queensland, Centre for Clinical Research, Brisbane, Australia; The University of Queensland, School of Health and Rehabilitation Sciences, Brisbane, Australia
| | - Matti Laine
- Åbo Akademi University, Department of Psychology, Turku, Finland
| | - Marcus Meinzer
- The University of Queensland, Centre for Clinical Research, Brisbane, Australia; University Medicine Greifswald, Department of Neurology, Greifswald, Germany.
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25
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Medaglia JD, Kuersten A, Hamilton RH. Protecting Decision-Making in the Era of Neuromodulation. JOURNAL OF COGNITIVE ENHANCEMENT 2020. [DOI: 10.1007/s41465-020-00171-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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26
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Bakulin I, Zabirova A, Lagoda D, Poydasheva A, Cherkasova A, Pavlov N, Kopnin P, Sinitsyn D, Kremneva E, Fedorov M, Gnedovskaya E, Suponeva N, Piradov M. Combining HF rTMS over the Left DLPFC with Concurrent Cognitive Activity for the Offline Modulation of Working Memory in Healthy Volunteers: A Proof-of-Concept Study. Brain Sci 2020; 10:brainsci10020083. [PMID: 32033106 PMCID: PMC7071618 DOI: 10.3390/brainsci10020083] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 01/31/2020] [Accepted: 02/03/2020] [Indexed: 01/28/2023] Open
Abstract
It has been proposed that the effectiveness of non-invasive brain stimulation (NIBS) as a cognitive enhancement technique may be enhanced by combining the stimulation with concurrent cognitive activity. However, the benefits of such a combination in comparison to protocols without ongoing cognitive activity have not yet been studied. In the present study, we investigate the effects of fMRI-guided high-frequency repetitive transcranial magnetic stimulation (HF rTMS) over the left dorsolateral prefrontal cortex (DLPFC) on working memory (WM) in healthy volunteers, using an n-back task with spatial and verbal stimuli and a spatial span task. In two combined protocols (TMS + WM + (maintenance) and TMS + WM + (rest)) trains of stimuli were applied in the maintenance and rest periods of the modified Sternberg task, respectively. We compared them to HF rTMS without a cognitive load (TMS + WM −) and control stimulation (TMS − WM + (maintenance)). No serious adverse effects appeared in this study. Among all protocols, significant effects on WM were shown only for the TMS + WM − with oppositely directed influences of this protocol on storage and manipulation in spatial WM. Moreover, there was a significant difference between the effects of TMS + WM − and TMS + WM + (maintenance), suggesting that simultaneous cognitive activity does not necessarily lead to an increase in TMS effects.
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Affiliation(s)
- Ilya Bakulin
- Research Center of Neurology, Volokolamskoe Shosse, 80, Moscow 125367, Russia; (A.Z.); (D.L.); (A.P.); (A.C.); (N.P.); (P.K.); (D.S.); (E.K.); (E.G.); (N.S.); (M.P.)
- Correspondence: ; Tel.: +7-495-490-2010
| | - Alfiia Zabirova
- Research Center of Neurology, Volokolamskoe Shosse, 80, Moscow 125367, Russia; (A.Z.); (D.L.); (A.P.); (A.C.); (N.P.); (P.K.); (D.S.); (E.K.); (E.G.); (N.S.); (M.P.)
| | - Dmitry Lagoda
- Research Center of Neurology, Volokolamskoe Shosse, 80, Moscow 125367, Russia; (A.Z.); (D.L.); (A.P.); (A.C.); (N.P.); (P.K.); (D.S.); (E.K.); (E.G.); (N.S.); (M.P.)
| | - Alexandra Poydasheva
- Research Center of Neurology, Volokolamskoe Shosse, 80, Moscow 125367, Russia; (A.Z.); (D.L.); (A.P.); (A.C.); (N.P.); (P.K.); (D.S.); (E.K.); (E.G.); (N.S.); (M.P.)
| | - Anastasiia Cherkasova
- Research Center of Neurology, Volokolamskoe Shosse, 80, Moscow 125367, Russia; (A.Z.); (D.L.); (A.P.); (A.C.); (N.P.); (P.K.); (D.S.); (E.K.); (E.G.); (N.S.); (M.P.)
| | - Nikolay Pavlov
- Research Center of Neurology, Volokolamskoe Shosse, 80, Moscow 125367, Russia; (A.Z.); (D.L.); (A.P.); (A.C.); (N.P.); (P.K.); (D.S.); (E.K.); (E.G.); (N.S.); (M.P.)
| | - Peter Kopnin
- Research Center of Neurology, Volokolamskoe Shosse, 80, Moscow 125367, Russia; (A.Z.); (D.L.); (A.P.); (A.C.); (N.P.); (P.K.); (D.S.); (E.K.); (E.G.); (N.S.); (M.P.)
| | - Dmitry Sinitsyn
- Research Center of Neurology, Volokolamskoe Shosse, 80, Moscow 125367, Russia; (A.Z.); (D.L.); (A.P.); (A.C.); (N.P.); (P.K.); (D.S.); (E.K.); (E.G.); (N.S.); (M.P.)
| | - Elena Kremneva
- Research Center of Neurology, Volokolamskoe Shosse, 80, Moscow 125367, Russia; (A.Z.); (D.L.); (A.P.); (A.C.); (N.P.); (P.K.); (D.S.); (E.K.); (E.G.); (N.S.); (M.P.)
| | - Maxim Fedorov
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard, 30, bld. 1, Territory of Innovation Center «Skolkovo», Moscow 121205, Russia;
| | - Elena Gnedovskaya
- Research Center of Neurology, Volokolamskoe Shosse, 80, Moscow 125367, Russia; (A.Z.); (D.L.); (A.P.); (A.C.); (N.P.); (P.K.); (D.S.); (E.K.); (E.G.); (N.S.); (M.P.)
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard, 30, bld. 1, Territory of Innovation Center «Skolkovo», Moscow 121205, Russia;
| | - Natalia Suponeva
- Research Center of Neurology, Volokolamskoe Shosse, 80, Moscow 125367, Russia; (A.Z.); (D.L.); (A.P.); (A.C.); (N.P.); (P.K.); (D.S.); (E.K.); (E.G.); (N.S.); (M.P.)
| | - Michael Piradov
- Research Center of Neurology, Volokolamskoe Shosse, 80, Moscow 125367, Russia; (A.Z.); (D.L.); (A.P.); (A.C.); (N.P.); (P.K.); (D.S.); (E.K.); (E.G.); (N.S.); (M.P.)
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27
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Effects of parietal exogenous oscillatory field potentials on subjectively perceived memory confidence. Neurobiol Learn Mem 2019; 168:107140. [PMID: 31843652 DOI: 10.1016/j.nlm.2019.107140] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 11/11/2019] [Accepted: 12/12/2019] [Indexed: 11/20/2022]
Abstract
Previous research suggests involvement of parietal theta (3-7 Hz) power in subjectively perceived memory confidence during retrieval. To obtain further insights into the role of parietal theta activity during retrieval in processes associated with performance and confidence, fifty-four healthy volunteers performed a recognition memory task in a within-subject sham controlled transcranial alternating current stimulation (tACS) study. Participants encoded a subset of words at specific on-screen locations. During the retrieval phase accuracy and subjectively perceived confidence on item and source memory were evaluated while administering exogenous alternating field potentials. Results showed that 3.5 Hz tACS decreased subjectively perceived memory confidence as compared to sham and 8 Hz tACS. No tACS effects were found on accuracy regarding item and source memory. Our findings suggest that theta activity in the parietal cortex is implicated in subjectively perceived confidence in word recognition.
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28
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Wynn SC, Driessen JMA, Glennon JC, Brazil IA, Schutter DJLG. Cerebellar Transcranial Direct Current Stimulation Improves Reactive Response Inhibition in Healthy Volunteers. CEREBELLUM (LONDON, ENGLAND) 2019; 18:983-988. [PMID: 31177388 PMCID: PMC6867976 DOI: 10.1007/s12311-019-01047-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Involvement of the cerebellum to non-motor related aspects of behavior is becoming increasingly clear. The aim of this study was to investigate the role of the cerebellum in reactive and proactive behavioral control and interference. In a double-blind controlled within-subject design, 26 healthy volunteers underwent real and sham cerebellar transcranial direct current stimulation (tDCS) while performing a go/no-go task and a delay discounting task. Results showed that the number of go/no-go commission errors was significantly lower during real as compared with sham cerebellar tDCS. No effects of tDCS were observed on delay discounting. Our findings provide further behavioral support for the involvement of the cerebellum in fast neural processes associated with response inhibition.
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Affiliation(s)
- Syanah C Wynn
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, P.O. Box 9104, 6500 HE, Nijmegen, The Netherlands
| | - Josi M A Driessen
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, P.O. Box 9104, 6500 HE, Nijmegen, The Netherlands.
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, 6525 GA, Nijmegen, The Netherlands.
| | - Jeffrey C Glennon
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, P.O. Box 9104, 6500 HE, Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, 6525 GA, Nijmegen, The Netherlands
| | - Inti A Brazil
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, P.O. Box 9104, 6500 HE, Nijmegen, The Netherlands
| | - Dennis J L G Schutter
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, P.O. Box 9104, 6500 HE, Nijmegen, The Netherlands
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29
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Wischnewski M, Schutter DJ, Nitsche MA. Effects of beta-tACS on corticospinal excitability: A meta-analysis. Brain Stimul 2019; 12:1381-1389. [DOI: 10.1016/j.brs.2019.07.023] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 07/05/2019] [Accepted: 07/25/2019] [Indexed: 01/08/2023] Open
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Abellaneda-Pérez K, Vaqué-Alcázar L, Solé-Padullés C, Bartrés-Faz D. Combining non-invasive brain stimulation with functional magnetic resonance imaging to investigate the neural substrates of cognitive aging. J Neurosci Res 2019; 100:1159-1170. [PMID: 31418480 DOI: 10.1002/jnr.24514] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 06/21/2019] [Accepted: 07/25/2019] [Indexed: 12/11/2022]
Abstract
As aging population is increasing, new methodologies to apprehend and enhance the mechanisms related to optimal brain function in advancing age become urgent. This review describes how the combined use of non-invasive brain stimulation (NIBS) with functional magnetic resonance imaging (fMRI) provides novel experimental data on the putative neurophysiological mechanisms underlying inter-individual differences in cognitive status among older adults, also further illuminating our understanding of theoretical models proposed within the cognitive neuroscience of aging literature. In addition, it explores published evidence of how this combined procedure entails the capacity to modify the activity and connectivity of specific brain networks in older adults, potentially leading to improvements in cognitive function and other measures reflecting mental health status. Although additional research is needed, combining NIBS with fMRI might provide innovative understanding of how fundamental brain plasticity mechanisms operate in advancing age, a knowledge that may be eventually used to refine more individually tailored approaches to promote brain health in aged populations.
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Affiliation(s)
- Kilian Abellaneda-Pérez
- Department of Medicine, Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain.,Institute of Neurosciences, University of Barcelona, Barcelona, Spain.,Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Lídia Vaqué-Alcázar
- Department of Medicine, Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain.,Institute of Neurosciences, University of Barcelona, Barcelona, Spain.,Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Cristina Solé-Padullés
- Department of Medicine, Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain.,Institute of Neurosciences, University of Barcelona, Barcelona, Spain.,Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - David Bartrés-Faz
- Department of Medicine, Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain.,Institute of Neurosciences, University of Barcelona, Barcelona, Spain.,Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), Barcelona, Spain
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31
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Davis SE, Smith GA. Transcranial Direct Current Stimulation Use in Warfighting: Benefits, Risks, and Future Prospects. Front Hum Neurosci 2019; 13:114. [PMID: 31105538 PMCID: PMC6499187 DOI: 10.3389/fnhum.2019.00114] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 03/14/2019] [Indexed: 12/26/2022] Open
Abstract
Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique which provides unique potential to directly improve human capability on a temporary, at needs, basis. The purpose of this paper is to consider the utility of tDCS through analysis of the potential risks and benefits in the context of defence service personnel. First, we look at the potential benefits, focusing primarily on warfighter survivability and enriching cognition quality in support of command and control. Second, we look at the potential detriments to tDCS military use, focusing on adverse effects, safety considerations, and risk. Third, we examine how the level of risk can be mitigated through military doctrine development focusing on safety parameters and exclusion criteria. Finally, we explore the future prospects of military tDCS use, particularly in terms of addressing gaps in the literature so that tDCS can be used ethically and efficaciously at the level of individual personnel.
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Affiliation(s)
- Steven E Davis
- Joint and Operational Analysis Division, Defence Science and Technology Group, Edinburgh, SA, Australia
| | - Glen A Smith
- Institute of Integrated and Intelligent Systems, Griffith University, Nathan, QLD, Australia
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Dresler M, Sandberg A, Bublitz C, Ohla K, Trenado C, Mroczko-Wąsowicz A, Kühn S, Repantis D. Hacking the Brain: Dimensions of Cognitive Enhancement. ACS Chem Neurosci 2019; 10:1137-1148. [PMID: 30550256 PMCID: PMC6429408 DOI: 10.1021/acschemneuro.8b00571] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 12/14/2018] [Indexed: 12/11/2022] Open
Abstract
In an increasingly complex information society, demands for cognitive functioning are growing steadily. In recent years, numerous strategies to augment brain function have been proposed. Evidence for their efficacy (or lack thereof) and side effects has prompted discussions about ethical, societal, and medical implications. In the public debate, cognitive enhancement is often seen as a monolithic phenomenon. On a closer look, however, cognitive enhancement turns out to be a multifaceted concept: There is not one cognitive enhancer that augments brain function per se, but a great variety of interventions that can be clustered into biochemical, physical, and behavioral enhancement strategies. These cognitive enhancers differ in their mode of action, the cognitive domain they target, the time scale they work on, their availability and side effects, and how they differentially affect different groups of subjects. Here we disentangle the dimensions of cognitive enhancement, review prominent examples of cognitive enhancers that differ across these dimensions, and thereby provide a framework for both theoretical discussions and empirical research.
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Affiliation(s)
- Martin Dresler
- Donders Institute for Brain, Cognition and Behaviour , Radboud University Medical Centre , Nijmegen 6525 EN , The Netherlands
| | - Anders Sandberg
- Future of Humanity Institute , Oxford University , Oxford OX1 1PT , United Kingdom
| | | | - Kathrin Ohla
- Institute of Neuroscience and Medicine, Cognitive Neuroscience (INM3) , Forschungszentrum Jülich , Jülich 52428 , Germany
| | - Carlos Trenado
- Institute of Clinical Neuroscience and Medical Psychology , Heinrich Heine University Düsseldorf , Düsseldorf 40225 , Germany
- Department of Psychology and Neurosciences, Leibniz Research Centre for Working Environment and Human Factors , TU Dortmund , Dortmund 44139 , Germany
| | | | - Simone Kühn
- Max Planck Institute for Human Development , Berlin 14195 , Germany
- Department of Psychiatry and Psychotherapy , University Clinic Hamburg Eppendorf , Hamburg 20246 , Germany
| | - Dimitris Repantis
- Department of Psychiatry and Psychotherapy, Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin 12203 , Germany
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Brem AK, Sensi SL. Towards Combinatorial Approaches for Preserving Cognitive Fitness in Aging. Trends Neurosci 2018; 41:885-897. [DOI: 10.1016/j.tins.2018.09.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 09/21/2018] [Accepted: 09/24/2018] [Indexed: 12/11/2022]
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34
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Modulating fluid intelligence performance through combined cognitive training and brain stimulation. Neuropsychologia 2018; 118:107-114. [DOI: 10.1016/j.neuropsychologia.2018.04.008] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 03/31/2018] [Accepted: 04/06/2018] [Indexed: 12/18/2022]
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35
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Wynn SC, Hendriks MPH, Daselaar SM, Kessels RPC, Schutter DJLG. The posterior parietal cortex and subjectively perceived confidence during memory retrieval. ACTA ACUST UNITED AC 2018; 25:382-389. [PMID: 30012883 PMCID: PMC6049393 DOI: 10.1101/lm.048033.118] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 06/15/2018] [Indexed: 12/20/2022]
Abstract
Functional neuroimaging studies suggest a role for the left angular gyrus (AG) in processes related to memory recognition. However, results of neuropsychological and transcranial magnetic stimulation (TMS) studies have been inconclusive regarding the specific contribution of the AG in recollection, familiarity, and the subjective experience of memory. To obtain further insight into this issue, 20 healthy right-handed volunteers performed a memory task in a single-blind within-subject controlled TMS study. Neuronavigated inhibitory repetitive TMS (rTMS) was applied over the left AG and the vertex in a randomized and counterbalanced order. Prior to rTMS participants were presented with a list of words. After rTMS participants were shown a second list of words and instructed to indicate if the word was already shown prior to rTMS ("old") or was presented for the first time ("new"). In addition, subjectively perceived memory confidence was assessed. Results showed that recollection was unaffected following inhibitory left AG rTMS. In contrast, rTMS over the left AG improved both familiarity and the subjectively perceived confidence of participants that demonstrated low baseline memory recognition. Our study highlights the importance of taking into account individual differences in experimental designs involving noninvasive brain stimulation.
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Affiliation(s)
- Syanah C Wynn
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, 6525 HP Nijmegen, The Netherlands
| | - Marc P H Hendriks
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, 6525 HP Nijmegen, The Netherlands.,Academic Centre of Epileptology, Kempenhaeghe, 5590 AB Heeze, The Netherlands
| | - Sander M Daselaar
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, 6525 HP Nijmegen, The Netherlands
| | - Roy P C Kessels
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, 6525 HP Nijmegen, The Netherlands
| | - Dennis J L G Schutter
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, 6525 HP Nijmegen, The Netherlands
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Wagner K, Maslen H, Oakley J, Savulescu J. Would you be willing to zap your child's brain? Public perspectives on parental responsibilities and the ethics of enhancing children with transcranial direct current stimulation. AJOB Empir Bioeth 2018; 9:29-38. [PMID: 29338674 PMCID: PMC6068541 DOI: 10.1080/23294515.2018.1424268] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
BACKGROUND Transcranial direct current stimulation (tDCS) is an experimental brain stimulation technology that may one day be used to enhance the cognitive capacities of children. Discussion about the ethical issues that this would raise has rarely moved beyond expert circles. However, the opinions of the wider public can lead to more democratic policy decisions and broaden academic discussion of this issue. METHODS We performed a quantitative survey of members of the U.S. public. A between-subjects design was employed, where conditions varied based on the trait respondents considered for enhancement. RESULTS There were 227 responses included for analysis. Our key finding was that the majority were unwilling to enhance their child with tDCS. Respondents were most reluctant to enhance traits considered fundamental to the self (such as motivation and empathy). However, many respondents may give in to implicit coercion to enhance their child in spite of an initial reluctance. A ban on tDCS was not supported if it were to be used safely for the enhancement of mood or mathematical ability. Opposition to such a ban may be related to the belief that tDCS use would not represent cheating or violate authenticity (as it relates to achievements rather than identity). CONCLUSIONS The wider public appears to think that crossing the line from treatment to enhancement with tDCS would not be in a child's best interests. However, an important alternative interpretation of our results is that lay people may be willing to use enhancers that matched their preference for "natural" enhancers. A ban on the safe use of tDCS for enhancing nonfundamental traits would be unlikely to garner public support. Nonetheless, it could become important to regulate tDCS in order to prevent misuse on children, because individuals reluctant to enhance may be likely to give in to implicit coercion to enhance their child.
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Affiliation(s)
- Katy Wagner
- Oxford Uehiro Centre for Practical Ethics, University of Oxford, and Faculty of Nursing, Medicine and Health Sciences, Monash University
| | - Hannah Maslen
- Oxford Uehiro Centre for Practical Ethics, University of Oxford
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Wexler A. Who Uses Direct-to-Consumer Brain Stimulation Products, and Why? A Study of Home Users of tDCS Devices. JOURNAL OF COGNITIVE ENHANCEMENT 2017. [DOI: 10.1007/s41465-017-0062-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Nelson JM, McKinley RA, McIntire LK, Goodyear C, Walters C. Augmenting Visual Search Performance With Transcranial Direct Current Stimulation (tDCS). MILITARY PSYCHOLOGY 2017. [DOI: 10.1037/mil0000085] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
| | - R. Andy McKinley
- 711th HPW, Applied Neuroscience Branch, U.S. Air Force Research Laboratory, Wright-Patterson AFB, Ohio
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Wischnewski M, Schutter DJ. After-effects of transcranial alternating current stimulation on evoked delta and theta power. Clin Neurophysiol 2017; 128:2227-2232. [DOI: 10.1016/j.clinph.2017.08.029] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 07/06/2017] [Accepted: 08/24/2017] [Indexed: 11/28/2022]
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Antal A, Alekseichuk I, Bikson M, Brockmöller J, Brunoni AR, Chen R, Cohen LG, Dowthwaite G, Ellrich J, Flöel A, Fregni F, George MS, Hamilton R, Haueisen J, Herrmann CS, Hummel FC, Lefaucheur JP, Liebetanz D, Loo CK, McCaig CD, Miniussi C, Miranda PC, Moliadze V, Nitsche MA, Nowak R, Padberg F, Pascual-Leone A, Poppendieck W, Priori A, Rossi S, Rossini PM, Rothwell J, Rueger MA, Ruffini G, Schellhorn K, Siebner HR, Ugawa Y, Wexler A, Ziemann U, Hallett M, Paulus W. Low intensity transcranial electric stimulation: Safety, ethical, legal regulatory and application guidelines. Clin Neurophysiol 2017; 128:1774-1809. [PMID: 28709880 PMCID: PMC5985830 DOI: 10.1016/j.clinph.2017.06.001] [Citation(s) in RCA: 670] [Impact Index Per Article: 95.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 05/29/2017] [Accepted: 06/06/2017] [Indexed: 12/11/2022]
Abstract
Low intensity transcranial electrical stimulation (TES) in humans, encompassing transcranial direct current (tDCS), transcutaneous spinal Direct Current Stimulation (tsDCS), transcranial alternating current (tACS), and transcranial random noise (tRNS) stimulation or their combinations, appears to be safe. No serious adverse events (SAEs) have been reported so far in over 18,000 sessions administered to healthy subjects, neurological and psychiatric patients, as summarized here. Moderate adverse events (AEs), as defined by the necessity to intervene, are rare, and include skin burns with tDCS due to suboptimal electrode-skin contact. Very rarely mania or hypomania was induced in patients with depression (11 documented cases), yet a causal relationship is difficult to prove because of the low incidence rate and limited numbers of subjects in controlled trials. Mild AEs (MAEs) include headache and fatigue following stimulation as well as prickling and burning sensations occurring during tDCS at peak-to-baseline intensities of 1-2mA and during tACS at higher peak-to-peak intensities above 2mA. The prevalence of published AEs is different in studies specifically assessing AEs vs. those not assessing them, being higher in the former. AEs are frequently reported by individuals receiving placebo stimulation. The profile of AEs in terms of frequency, magnitude and type is comparable in healthy and clinical populations, and this is also the case for more vulnerable populations, such as children, elderly persons, or pregnant women. Combined interventions (e.g., co-application of drugs, electrophysiological measurements, neuroimaging) were not associated with further safety issues. Safety is established for low-intensity 'conventional' TES defined as <4mA, up to 60min duration per day. Animal studies and modeling evidence indicate that brain injury could occur at predicted current densities in the brain of 6.3-13A/m2 that are over an order of magnitude above those produced by tDCS in humans. Using AC stimulation fewer AEs were reported compared to DC. In specific paradigms with amplitudes of up to 10mA, frequencies in the kHz range appear to be safe. In this paper we provide structured interviews and recommend their use in future controlled studies, in particular when trying to extend the parameters applied. We also discuss recent regulatory issues, reporting practices and ethical issues. These recommendations achieved consensus in a meeting, which took place in Göttingen, Germany, on September 6-7, 2016 and were refined thereafter by email correspondence.
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Affiliation(s)
- A Antal
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Georg August University, Göttingen, Germany.
| | - I Alekseichuk
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Georg August University, Göttingen, Germany
| | - M Bikson
- Department of Biomedical Engineering, The City College of New York, New York, USA
| | - J Brockmöller
- Department of Clinical Pharmacology, University Medical Center Goettingen, Germany
| | - A R Brunoni
- Service of Interdisciplinary Neuromodulation, Department and Institute of Psychiatry, Laboratory of Neurosciences (LIM-27) and Interdisciplinary Center for Applied Neuromodulation University Hospital, University of São Paulo, São Paulo, Brazil
| | - R Chen
- Division of Neurology, Department of Medicine, University of Toronto and Krembil Research Institute, Toronto, Ontario, Canada
| | - L G Cohen
- Human Cortical Physiology and Neurorehabilitation Section, National Institute of Neurological Disorders and Stroke NIH, Bethesda, USA
| | | | - J Ellrich
- Department of Health Science and Technology, Aalborg University, Aalborg, Denmark; Institute of Physiology and Pathophysiology, University of Erlangen-Nürnberg, Erlangen, Germany; EBS Technologies GmbH, Europarc Dreilinden, Germany
| | - A Flöel
- Universitätsmedizin Greifswald, Klinik und Poliklinik für Neurologie, Greifswald, Germany
| | - F Fregni
- Spaulding Neuromodulation Center, Spaulding Rehabilitation Hospital, Harvard Medical School, Boston, MA, USA
| | - M S George
- Brain Stimulation Division, Medical University of South Carolina, and Ralph H. Johnson Veterans Affairs Medical Center, Charleston, SC, USA
| | - R Hamilton
- Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA
| | - J Haueisen
- Institute of Biomedical Engineering and Informatics, Technische Universität Ilmenau, Germany
| | - C S Herrmann
- Experimental Psychology Lab, Department of Psychology, European Medical School, Carl von Ossietzky Universität, Oldenburg, Germany
| | - F C Hummel
- Defitech Chair of Clinical Neuroengineering, Centre of Neuroprosthetics (CNP) and Brain Mind Institute, Swiss Federal Institute of Technology (EPFL), Geneva, Switzerland; Defitech Chair of Clinical Neuroengineering, Clinique Romande de Réadaptation, Swiss Federal Institute of Technology (EPFL Valais), Sion, Switzerland
| | - J P Lefaucheur
- Department of Physiology, Henri Mondor Hospital, Assistance Publique - Hôpitaux de Paris, and EA 4391, Nerve Excitability and Therapeutic Team (ENT), Faculty of Medicine, Paris Est Créteil University, Créteil, France
| | - D Liebetanz
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Georg August University, Göttingen, Germany
| | - C K Loo
- School of Psychiatry & Black Dog Institute, University of New South Wales, Sydney, Australia
| | - C D McCaig
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, Scotland, UK
| | - C Miniussi
- Center for Mind/Brain Sciences CIMeC, University of Trento, Rovereto, Italy; Cognitive Neuroscience Section, IRCCS Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy
| | - P C Miranda
- Institute of Biophysics and Biomedical Engineering, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal
| | - V Moliadze
- Institute of Medical Psychology and Medical Sociology, University Hospital of Schleswig-Holstein (UKSH), Campus Kiel, Christian-Albrechts-University, Kiel, Germany
| | - M A Nitsche
- Department of Psychology and Neurosciences, Leibniz Research Centre for Working Environment and Human Factors, Dortmund, Germany; Department of Neurology, University Hospital Bergmannsheil, Bochum, Germany
| | - R Nowak
- Neuroelectrics, Barcelona, Spain
| | - F Padberg
- Department of Psychiatry and Psychotherapy, Munich Center for Brain Stimulation, Ludwig-Maximilian University Munich, Germany
| | - A Pascual-Leone
- Division of Cognitive Neurology, Harvard Medical Center and Berenson-Allen Center for Noninvasive Brain Stimulation at Beth Israel Deaconess Medical Center, Boston, USA
| | - W Poppendieck
- Department of Information Technology, Mannheim University of Applied Sciences, Mannheim, Germany
| | - A Priori
- Center for Neurotechnology and Experimental Brain Therapeutich, Department of Health Sciences, University of Milan Italy; Deparment of Clinical Neurology, University Hospital Asst Santi Paolo E Carlo, Milan, Italy
| | - S Rossi
- Department of Medicine, Surgery and Neuroscience, Human Physiology Section and Neurology and Clinical Neurophysiology Section, Brain Investigation & Neuromodulation Lab, University of Siena, Italy
| | - P M Rossini
- Area of Neuroscience, Institute of Neurology, University Clinic A. Gemelli, Catholic University, Rome, Italy
| | | | - M A Rueger
- Department of Neurology, University Hospital of Cologne, Germany
| | | | | | - H R Siebner
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark; Department of Neurology, Copenhagen University Hospital Bispebjerg, Copenhagen, Denmark
| | - Y Ugawa
- Department of Neurology, Fukushima Medical University, Fukushima, Japan; Fukushima Global Medical Science Center, Advanced Clinical Research Center, Fukushima Medical University, Japan
| | - A Wexler
- Department of Science, Technology & Society, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - U Ziemann
- Department of Neurology & Stroke, and Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - M Hallett
- Human Motor Control Section, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD, USA
| | - W Paulus
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Georg August University, Göttingen, Germany
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Martin AK, Meinzer M, Lindenberg R, Sieg MM, Nachtigall L, Flöel A. Effects of Transcranial Direct Current Stimulation on Neural Networks in Young and Older Adults. J Cogn Neurosci 2017; 29:1817-1828. [PMID: 28707568 DOI: 10.1162/jocn_a_01166] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Transcranial direct current stimulation (tDCS) may be a viable tool to improve motor and cognitive function in advanced age. However, although a number of studies have demonstrated improved cognitive performance in older adults, other studies have failed to show restorative effects. The neural effects of beneficial stimulation response in both age groups is lacking. In the current study, tDCS was administered during simultaneous fMRI in 42 healthy young and older participants. Semantic word generation and motor speech baseline tasks were used to investigate behavioral and neural effects of uni- and bihemispheric motor cortex tDCS in a three-way, crossover, sham tDCS controlled design. Independent components analysis assessed differences in task-related activity between the two age groups and tDCS effects at the network level. We also explored whether laterality of language network organization was effected by tDCS. Behaviorally, both active tDCS conditions significantly improved semantic word retrieval performance in young and older adults and were comparable between groups and stimulation conditions. Network-level tDCS effects were identified in the ventral and dorsal anterior cingulate networks in the combined sample during semantic fluency and motor speech tasks. In addition, a shift toward enhanced left laterality was identified in the older adults for both active stimulation conditions. Thus, tDCS results in common network-level modulations and behavioral improvements for both age groups, with an additional effect of increasing left laterality in older adults.
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Affiliation(s)
| | | | | | - Mira M Sieg
- Charité University Medicine, Berlin, Germany
| | | | - Agnes Flöel
- Charité University Medicine, Berlin, Germany.,University of Greifswald
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Looi CY, Lim J, Sella F, Lolliot S, Duta M, Avramenko AA, Cohen Kadosh R. Transcranial random noise stimulation and cognitive training to improve learning and cognition of the atypically developing brain: A pilot study. Sci Rep 2017; 7:4633. [PMID: 28680099 PMCID: PMC5498607 DOI: 10.1038/s41598-017-04649-x] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 05/18/2017] [Indexed: 12/27/2022] Open
Abstract
Learning disabilities that affect about 10% of human population are linked to atypical neurodevelopment, but predominantly treated by behavioural interventions. Behavioural interventions alone have shown little efficacy, indicating limited success in modulating neuroplasticity, especially in brains with neural atypicalities. Even in healthy adults, weeks of cognitive training alone led to inconsistent generalisable training gains, or "transfer effects" to non-trained materials. Meanwhile, transcranial random noise stimulation (tRNS), a painless and more direct neuromodulation method was shown to further promote cognitive training and transfer effects in healthy adults without harmful effects. It is unknown whether tRNS on the atypically developing brain might promote greater learning and transfer outcomes than training alone. Here, we show that tRNS over the bilateral dorsolateral prefrontal cortices (dlPFCs) improved learning and performance of children with mathematical learning disabilities (MLD) during arithmetic training compared to those who received sham (placebo) tRNS. Training gains correlated positively with improvement on a standardized mathematical diagnostic test, and this effect was strengthened by tRNS. These findings mirror those in healthy adults, and encourage replications using larger cohorts. Overall, this study offers insights into the concept of combining tRNS and cognitive training for improving learning and cognition of children with learning disabilities.
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Affiliation(s)
- Chung Yen Looi
- Department of Experimental Psychology, University of Oxford, Oxford, OX1 3UD, United Kingdom
| | - Jenny Lim
- Fairley House School, London, SW1P 4AU, UK
| | - Francesco Sella
- Department of Experimental Psychology, University of Oxford, Oxford, OX1 3UD, United Kingdom
| | - Simon Lolliot
- Department of Experimental Psychology, University of Oxford, Oxford, OX1 3UD, United Kingdom
| | - Mihaela Duta
- Department of Experimental Psychology, University of Oxford, Oxford, OX1 3UD, United Kingdom
| | | | - Roi Cohen Kadosh
- Department of Experimental Psychology, University of Oxford, Oxford, OX1 3UD, United Kingdom.
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Reteig LC, Talsma LJ, van Schouwenburg MR, Slagter HA. Transcranial Electrical Stimulation as a Tool to Enhance Attention. JOURNAL OF COGNITIVE ENHANCEMENT 2017. [DOI: 10.1007/s41465-017-0010-y] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Davis NJ. Prefrontal electrical stimulation in non-depressed reduces levels of reported negative affects from daily stressors. Front Hum Neurosci 2017; 11:63. [PMID: 28261075 PMCID: PMC5306201 DOI: 10.3389/fnhum.2017.00063] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 01/30/2017] [Indexed: 01/17/2023] Open
Abstract
Advances in neuroscience and pharmacology have led to improvements in the cognitive performance of people with neurological disease and other forms of cognitive decline. These same methods may also afford cognitive enhancement in people of otherwise normal cognitive abilities. “Cosmetic”, or supranormal, cognitive enhancement offers opportunities to enrich our social or financial status, our interactions with others, and the common wealth of our community. It is common to focus on the potential benefits of cognitive enhancement, while being less than clear about the possible drawbacks. Here I examine the harms or side-effects associated with a range of cognitive enhancement interventions. I propose a taxonomy of harms in cognitive enhancement, with harms classified as (neuro)biological, ethical, or societal. Biological harms are those that directly affect the person’s biological functioning, such as when a drug affects a person’s mood or autonomic function. Ethical harms are those that touch on issues such as fairness and cheating, or on erosion of autonomy and coercion. Societal harms are harms that affect whole populations, and which are normally the province of governments, such as the use of enhancement in military contexts. This taxonomy of harms will help to focus the debate around the use and regulation of cognitive enhancement. In particular it will help to clarify the appropriate network of stakeholders who should take an interest in each potential harm, and in minimizing the impact of these harms.
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Affiliation(s)
- Nick J Davis
- Department of Psychology, Manchester Metropolitan University Manchester, UK
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Voarino N, Dubljević V, Racine E. tDCS for Memory Enhancement: Analysis of the Speculative Aspects of Ethical Issues. Front Hum Neurosci 2017; 10:678. [PMID: 28123362 PMCID: PMC5225120 DOI: 10.3389/fnhum.2016.00678] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 12/20/2016] [Indexed: 11/26/2022] Open
Abstract
Transcranial direct current stimulation (tDCS) is a promising technology to enhance cognitive and physical performance. One of the major areas of interest is the enhancement of memory function in healthy individuals. The early arrival of tDCS on the market for lifestyle uses and cognitive enhancement purposes lead to the voicing of some important ethical concerns, especially because, to date, there are no official guidelines or evaluation procedures to tackle these issues. The aim of this article is to review ethical issues related to uses of tDCS for memory enhancement found in the ethics and neuroscience literature and to evaluate how realistic and scientifically well-founded these concerns are? In order to evaluate how plausible or speculative each issue is, we applied the methodological framework described by Racine et al. (2014) for “informed and reflective” speculation in bioethics. This framework could be succinctly presented as requiring: (1) the explicit acknowledgment of factual assumptions and identification of the value attributed to them; (2) the validation of these assumptions with interdisciplinary literature; and (3) the adoption of a broad perspective to support more comprehensive reflection on normative issues. We identified four major considerations associated with the development of tDCS for memory enhancement: safety, autonomy, justice and authenticity. In order to assess the seriousness and likelihood of harm related to each of these concerns, we analyzed the assumptions underlying the ethical issues, and the level of evidence for each of them. We identified seven distinct assumptions: prevalence, social acceptance, efficacy, ideological stance (bioconservative vs. libertarian), potential for misuse, long term side effects, and the delivery of complete and clear information. We conclude that ethical discussion about memory enhancement via tDCS sometimes involves undue speculation, and closer attention to scientific and social facts would bring a more nuanced analysis. At this time, the most realistic concerns are related to safety and violation of users’ autonomy by a breach of informed consent, as potential immediate and long-term health risks to private users remain unknown or not well defined. Clear and complete information about these risks must be provided to research participants and consumers of tDCS products or related services. Broader public education initiatives and warnings would also be worthwhile to reach those who are constructing their own tDCS devices.
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Affiliation(s)
- Nathalie Voarino
- Institut de recherches cliniques de Montréal, Université de Montréal, McGill UniversityMontreal, QC, Canada; Bioethics Programme, Department of Social and Preventive Medicine, School of Public Health (ÉSPUM), Université de MontréalMontreal, QC, Canada
| | - Veljko Dubljević
- North Carolina State UniversityRaleigh, NC, USA; Neuroethics Research Unit, Institut de recherches cliniques de MontréalMontreal, QC, Canada
| | - Eric Racine
- Institut de recherches cliniques de Montréal, Université de Montréal, McGill University Montreal, QC, Canada
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Abstract
PURPOSE OF REVIEW The review aims at highlighting the additional benefit that can be gained from combining noninvasive brain stimulation as well as repetitive sensory stimulation protocols with MRI techniques to account for the intersubject variability observed in those treatments. Potentially, this should help to identify predictive patterns in the individual receptiveness to the treatment. RECENT FINDINGS Knowledge about the underlying physiological principles of excitability changes as induced by noninvasive brain stimulation or repetitive sensory stimulation is accumulating, revealing strong associations with plasticity processes at the synaptic level. In this context, MRI techniques, such as magnetic resonance spectroscopy and functional MRI, emerged as valuable tools for the qualitative assessment of baseline states and induced changes. Those physiological readouts can help explain the interindividual heterogeneity found in behavioural and/or clinical responses to the specific stimulation protocols. This knowledge will eventually translate, first, into the preliminary classification of study participants into treatment groups according to their neurophysiological baseline state and expected responses to a particular stimulation. Subsequently, this should also aid the optimization of stimulation protocols according to the classification outcome, resulting in retuned protocols for particular groups of study participants. SUMMARY The consistent MRI-based monitoring of stimulation effects in the neural network promises a considerable gain for the customization of intervention protocols with improved therapeutic potential and rehabilitative predictions.
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Nelson J, McKinley RA, Phillips C, McIntire L, Goodyear C, Kreiner A, Monforton L. The Effects of Transcranial Direct Current Stimulation (tDCS) on Multitasking Throughput Capacity. Front Hum Neurosci 2016; 10:589. [PMID: 27965553 PMCID: PMC5126079 DOI: 10.3389/fnhum.2016.00589] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 11/04/2016] [Indexed: 11/29/2022] Open
Abstract
Background: Multitasking has become an integral attribute associated with military operations within the past several decades. As the amount of information that needs to be processed during these high level multitasking environments exceeds the human operators' capabilities, the information throughput capacity reaches an asymptotic limit. At this point, the human operator can no longer effectively process and respond to the incoming information resulting in a plateau or decline in performance. The objective of the study was to evaluate the efficacy of a non-invasive brain stimulation technique known as transcranial direct current stimulation (tDCS) applied to a scalp location over the left dorsolateral prefrontal cortex (lDLPFC) to improve information processing capabilities during a multitasking environment. Methods: The study consisted of 20 participants from Wright-Patterson Air Force Base (16 male and 4 female) with an average age of 31.1 (SD = 4.5). Participants were randomly assigned into two groups, each consisting of eight males and two females. Group one received 2 mA of anodal tDCS and group two received sham tDCS over the lDLPFC on their testing day. Results: The findings indicate that anodal tDCS significantly improves the participants' information processing capability resulting in improved performance compared to sham tDCS. For example, the multitasking throughput capacity for the sham tDCS group plateaued near 1.0 bits/s at the higher baud input (2.0 bits/s) whereas the anodal tDCS group plateaued near 1.3 bits/s. Conclusion: The findings provided new evidence that tDCS has the ability to augment and enhance multitasking capability in a human operator. Future research should be conducted to determine the longevity of the enhancement of transcranial direct current stimulation on multitasking performance, which has yet to be accomplished.
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Affiliation(s)
- Justin Nelson
- Air Force Research Laboratory, Wright-Patterson Air Force BaseOH, USA
| | | | - Chandler Phillips
- Department of Biomedical, Industrial, and Human Factors Engineering, Wright State UniversityDayton, OH, USA
| | - Lindsey McIntire
- Air Force Research Laboratory, Wright-Patterson Air Force BaseOH, USA
| | - Chuck Goodyear
- Air Force Research Laboratory, Wright-Patterson Air Force BaseOH, USA
| | - Aerial Kreiner
- Air Force Research Laboratory, Wright-Patterson Air Force BaseOH, USA
| | - Lanie Monforton
- Department of Biomedical, Industrial, and Human Factors Engineering, Wright State UniversityDayton, OH, USA
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Increased contextual cue utilization with tDCS over the prefrontal cortex during a recognition task. Brain Res 2016; 1655:1-9. [PMID: 27845032 DOI: 10.1016/j.brainres.2016.11.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 10/07/2016] [Accepted: 11/08/2016] [Indexed: 11/22/2022]
Abstract
The precise role of the prefrontal and posterior parietal cortices in recognition performance remains controversial, with questions about whether these regions contribute to recognition via the availability of mnemonic evidence or via decision biases and retrieval orientation. Here we used an explicit memory cueing paradigm, whereby external cues probabilistically predict upcoming memoranda as old or new, in our case with 75% validity, and these cues affect recognition decision biases in the direction of the cue. The present study applied bilateral transcranial direct current stimulation (tDCS) over prefrontal or posterior parietal cortex, or sham tDCS, to test the causal role of these regions in recognition accuracy or decision biasing. Participants who received tDCS over prefrontal cortex showed increased cue utilization compared to tDCS over posterior parietal cortex and sham tDCS, suggesting that the prefrontal cortex is involved in processes that contribute to decision biases in memory.
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Evidence-based guidelines on the therapeutic use of transcranial direct current stimulation (tDCS). Clin Neurophysiol 2016; 128:56-92. [PMID: 27866120 DOI: 10.1016/j.clinph.2016.10.087] [Citation(s) in RCA: 1044] [Impact Index Per Article: 130.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 10/18/2016] [Accepted: 10/20/2016] [Indexed: 12/19/2022]
Abstract
A group of European experts was commissioned by the European Chapter of the International Federation of Clinical Neurophysiology to gather knowledge about the state of the art of the therapeutic use of transcranial direct current stimulation (tDCS) from studies published up until September 2016, regarding pain, Parkinson's disease, other movement disorders, motor stroke, poststroke aphasia, multiple sclerosis, epilepsy, consciousness disorders, Alzheimer's disease, tinnitus, depression, schizophrenia, and craving/addiction. The evidence-based analysis included only studies based on repeated tDCS sessions with sham tDCS control procedure; 25 patients or more having received active treatment was required for Class I, while a lower number of 10-24 patients was accepted for Class II studies. Current evidence does not allow making any recommendation of Level A (definite efficacy) for any indication. Level B recommendation (probable efficacy) is proposed for: (i) anodal tDCS of the left primary motor cortex (M1) (with right orbitofrontal cathode) in fibromyalgia; (ii) anodal tDCS of the left dorsolateral prefrontal cortex (DLPFC) (with right orbitofrontal cathode) in major depressive episode without drug resistance; (iii) anodal tDCS of the right DLPFC (with left DLPFC cathode) in addiction/craving. Level C recommendation (possible efficacy) is proposed for anodal tDCS of the left M1 (or contralateral to pain side, with right orbitofrontal cathode) in chronic lower limb neuropathic pain secondary to spinal cord lesion. Conversely, Level B recommendation (probable inefficacy) is conferred on the absence of clinical effects of: (i) anodal tDCS of the left temporal cortex (with right orbitofrontal cathode) in tinnitus; (ii) anodal tDCS of the left DLPFC (with right orbitofrontal cathode) in drug-resistant major depressive episode. It remains to be clarified whether the probable or possible therapeutic effects of tDCS are clinically meaningful and how to optimally perform tDCS in a therapeutic setting. In addition, the easy management and low cost of tDCS devices allow at home use by the patient, but this might raise ethical and legal concerns with regard to potential misuse or overuse. We must be careful to avoid inappropriate applications of this technique by ensuring rigorous training of the professionals and education of the patients.
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