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Posar A, Visconti P. Continuous Spike-Waves during Slow Sleep Today: An Update. CHILDREN (BASEL, SWITZERLAND) 2024; 11:169. [PMID: 38397281 PMCID: PMC10887038 DOI: 10.3390/children11020169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 01/19/2024] [Accepted: 01/26/2024] [Indexed: 02/25/2024]
Abstract
In the context of childhood epilepsy, the concept of continuous spike-waves during slow sleep (CSWS) includes several childhood-onset heterogeneous conditions that share electroencephalograms (EEGs) characterized by a high frequency of paroxysmal abnormalities during sleep, which have negative effects on the cognitive development and behavior of the child. These negative effects may have the characteristics of a clear regression or of a slowdown in development. Seizures are very often present, but not constantly. The above makes it clear why CSWS have been included in epileptic encephalopathies, in which, by definition, frequent EEG paroxysmal abnormalities have an unfavorable impact on cognitive functions, including socio-communicative skills, causing autistic features, even regardless of the presence of clinically overt seizures. Although several decades have passed since the original descriptions of the electroclinical condition of CSWS, there are still many areas that are little-known and deserve to be further studied, including the EEG diagnostic criteria, the most effective electrophysiological parameter for monitoring the role of the thalamus in CSWS pathogenesis, its long-term evolution, the nosographic location of Landau-Kleffner syndrome, standardized neuropsychological and behavioral assessments, and pharmacological and non-pharmacological therapies.
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Affiliation(s)
- Annio Posar
- IRCCS Istituto delle Scienze Neurologiche di Bologna, UOSI Disturbi dello Spettro Autistico, 40139 Bologna, Italy;
- Department of Biomedical and Neuromotor Sciences, Bologna University, 40139 Bologna, Italy
| | - Paola Visconti
- IRCCS Istituto delle Scienze Neurologiche di Bologna, UOSI Disturbi dello Spettro Autistico, 40139 Bologna, Italy;
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Ashrafzadeh F, Akhondian J, Hashemi N, Esmaeilzadeh M, Ghanaee A, Yavarzadeh H, Imannezhad S, Saeedi Zand N, Mirzadeh HS, Beiraghi Toosi M. Therapeutical impacts of transcranial direct current stimulation on drug-resistant epilepsy in pediatric patients: A double-blind parallel-group randomized clinical trial. Epilepsy Res 2023; 190:107074. [PMID: 36657251 DOI: 10.1016/j.eplepsyres.2022.107074] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 08/14/2022] [Accepted: 12/30/2022] [Indexed: 01/07/2023]
Abstract
BACKGROUND Drug-resistant epilepsy is a challenging problem in pediatrics. Transcranial direct current stimulation (TDCS) is a non-invasive neurostimulation technique suggested as a promising method for treating epilepsy. This study aims to evaluate the efficacy of TDCS in focal epilepsy in children with drug-resistant epilepsy. METHOD We conducted a randomized sham-controlled study with 18 subjects between 6 and 16 years of age, divided equally into two groups. TDCS was performed in 20-minute daily stimulation protocol for five days for both groups. The current intensity was one mA for the first three days, increasing to 1.5 mA on day four and 2 mA on the last day of stimulation. EEG was done before and after the intervention. RESULTS There was a significant reduction in seizure duration in the case group compared with the sham group. CONCLUSION five consecutive days of performing TDCS significantly reduced seizure duration in children with focal Drug-resistant epilepsy. However,further studies in this field are necessary to test the effectiveness and set up a coherent and comprehensive protocol.
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Affiliation(s)
- Farah Ashrafzadeh
- Department of Pediatrics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Javad Akhondian
- Department of Pediatrics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Narges Hashemi
- Department of Pediatrics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mahla Esmaeilzadeh
- Student Research Committee (SRC), Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Ali Ghanaee
- Department of Psychology, Faculty of Education and Psychology, Ferdowsi University, Mashhad, Iran
| | - Hanieh Yavarzadeh
- MA Student of Psychology, Faculty of Education and Psychology, Ferdowsi University, Mashhad, Iran
| | - Shima Imannezhad
- Department of Pediatrics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Nazanin Saeedi Zand
- Department of Pediatrics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Hanieh Sadat Mirzadeh
- Department of Pediatrics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mehran Beiraghi Toosi
- Department of Pediatrics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
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Ng MC, El-Alawi H, Toutant D, Choi EH, Wright N, Khanam M, Paunovic B, Ko JH. A Pilot Study of High-Definition Transcranial Direct Current Stimulation in Refractory Status Epilepticus: The SURESTEP Trial. Neurotherapeutics 2023; 20:181-194. [PMID: 36323975 PMCID: PMC9629761 DOI: 10.1007/s13311-022-01317-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/10/2022] [Indexed: 12/13/2022] Open
Abstract
Refractory status epilepticus (RSE) is a life-threatening emergency with high mortality and poor functional outcomes in survivors. Treatment is typically limited to intravenous anesthetic infusions and multiple anti-seizure medications. While ongoing seizures can cause permanent neurological damage, medical therapies also pose severe and life-threatening side effects. We tested the feasibility of using high-definition transcranial direct current stimulation (hd-tDCS) in the treatment of RSE. We conducted 20-min hd-tDCS sessions at an outward field orientation, intensity of 2-mA, 4 + 1 channels, and customized for deployment over the electrographic maximum of epileptiform activity ("spikes") determined by real-time clinical EEG monitoring. There were no adverse events from 32 hd-tDCS sessions in 10 RSE patients. Over steady dosing states of infusions and medications in 29 included sessions, median spike rates/patient fell by 50% during hd-tDCS on both automated (p = 0.0069) and human (p = 0.0277) spike counting. Median spike rates for any given stimulation session also fell by 50% during hd-tDCS on automated spike counting (p = 0.0032). Immediately after hd-tDCS, median spike rates/patient remained down by 25% on human spike counting (p = 0.018). Compared to historical controls, hd-tDCS subjects were successfully discharged from the intensive care unit (ICU) 45.8% more often (p = 0.004). When controls were selected using propensity score matching, the discharge rate advantage improved to 55% (p = 0.002). Customized EEG electrode targeting of hd-tDCS is a safe and non-invasive method of hyperacutely reducing epileptiform activity in RSE. Compared to historical controls, there was evidence of a cumulative chronic clinical response with more hd-tDCS subjects discharged from ICU.
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Affiliation(s)
- Marcus C Ng
- Section of Neurology, Department of Internal Medicine, University of Manitoba, Winnipeg, Canada.
- Undergraduate Medical Education, Max Rady College of Medicine, University of Manitoba, Winnipeg, Canada.
- Graduate Program in Biomedical Engineering, University of Manitoba, Winnipeg, Canada.
| | - Hussam El-Alawi
- Undergraduate Medical Education, Max Rady College of Medicine, University of Manitoba, Winnipeg, Canada
| | - Darion Toutant
- Graduate Program in Biomedical Engineering, University of Manitoba, Winnipeg, Canada
| | - Eun Hyung Choi
- Department of Human Anatomy and Cell Science, University of Manitoba, Winnipeg, Canada
| | - Natalie Wright
- Department of Human Anatomy and Cell Science, University of Manitoba, Winnipeg, Canada
| | - Manzuma Khanam
- Department of Human Anatomy and Cell Science, University of Manitoba, Winnipeg, Canada
| | - Bojan Paunovic
- Undergraduate Medical Education, Max Rady College of Medicine, University of Manitoba, Winnipeg, Canada
- Section of Critical Care Medicine, Department of Internal Medicine, University of Manitoba, Winnipeg, Canada
| | - Ji Hyun Ko
- Graduate Program in Biomedical Engineering, University of Manitoba, Winnipeg, Canada.
- Department of Human Anatomy and Cell Science, University of Manitoba, Winnipeg, Canada.
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Simula S, Daoud M, Ruffini G, Biagi MC, Bénar CG, Benquet P, Wendling F, Bartolomei F. Transcranial current stimulation in epilepsy: A systematic review of the fundamental and clinical aspects. Front Neurosci 2022; 16:909421. [PMID: 36090277 PMCID: PMC9453675 DOI: 10.3389/fnins.2022.909421] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 07/18/2022] [Indexed: 11/13/2022] Open
Abstract
Purpose Transcranial electrical current stimulation (tES or tCS, as it is sometimes referred to) has been proposed as non-invasive therapy for pharmacoresistant epilepsy. This technique, which includes direct current (tDCS) and alternating current (tACS) stimulation involves the application of weak currents across the cortex to change cortical excitability. Although clinical trials have demonstrated the therapeutic efficacy of tES, its specific effects on epileptic brain activity are poorly understood. We sought to summarize the clinical and fundamental effects underlying the application of tES in epilepsy. Methods A systematic review was performed in accordance with the PRISMA guidelines. A database search was performed in PUBMED, MEDLINE, Web of Science and Cochrane CENTRAL for articles corresponding to the keywords “epilepsy AND (transcranial current stimulation OR transcranial electrical stimulation)”. Results A total of 56 studies were included in this review. Through these records, we show that tDCS and tACS epileptic patients are safe and clinically relevant techniques for epilepsy. Recent articles reported changes of functional connectivity in epileptic patients after tDCS. We argue that tDCS may act by affecting brain networks, rather than simply modifying local activity in the targeted area. To explain the mechanisms of tES, various cellular effects have been identified. Among them, reduced cell loss, mossy fiber sprouting, and hippocampal BDNF protein levels. Brain modeling and human studies highlight the influence of individual brain anatomy and physiology on the electric field distribution. Computational models may optimize the stimulation parameters and bring new therapeutic perspectives. Conclusion Both tDCS and tACS are promising techniques for epilepsy patients. Although the clinical effects of tDCS have been repeatedly assessed, only one clinical trial has involved a consistent number of epileptic patients and little knowledge is present about the clinical outcome of tACS. To fill this gap, multicenter studies on tES in epileptic patients are needed involving novel methods such as personalized stimulation protocols based on computational modeling. Furthermore, there is a need for more in vivo studies replicating the tES parameters applied in patients. Finally, there is a lack of clinical studies investigating changes in intracranial epileptiform discharges during tES application, which could clarify the nature of tES-related local and network dynamics in epilepsy.
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Affiliation(s)
- Sara Simula
- Aix Marseille Univ, INSERM, INS, Int Neurosci Syst, Marseille, France
| | - Maëva Daoud
- Aix Marseille Univ, INSERM, INS, Int Neurosci Syst, Marseille, France
| | | | | | | | | | | | - Fabrice Bartolomei
- Aix Marseille Univ, INSERM, INS, Int Neurosci Syst, Marseille, France
- APHM, Timone Hospital, Epileptology and Cerebral Rhythmology, Marseille, France
- *Correspondence: Fabrice Bartolomei
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Safety and efficacy of cathodal transcranial direct current stimulation in patients with Lennox Gastaut Syndrome: An open-label, prospective, single-center, single-blinded, pilot study. Seizure 2022; 100:44-50. [PMID: 35751952 DOI: 10.1016/j.seizure.2022.06.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 06/14/2022] [Accepted: 06/16/2022] [Indexed: 11/20/2022] Open
Abstract
PURPOSE Lennox-Gastaut Syndrome (SLG) is a severe form of childhood refractory epilepsy. Only one pilot study has been conducted using cathodal transcranial direct current stimulation (c-tDCs; 2mAx30minx5days) in LGS with promising results (-99% seizure reduction at 5 days). Our aim was to explore and replicate the efficacy and safety of 10 daily sessions of c-tDCs in SLG. METHODS We conducted a one-blinded, single-center pilot clinical study of c-tDCs (2mAx 30 min x 10 days), applied over the highest amplitude or frequent epileptiform interictal discharges areas using scalp EEG recordings without changes in their treatments. The tDCS device used was Enobio EEG® (Neuroelectrics, Barcelona, Spain). The primary outcome was based on the seizure frequency using seizure diaries before, during 10 days of treatment, and then on a 4 and 8 weeks of follow-up. The rate of adverse events was recorded as a secondary outcome. Descriptive statistics and Wilcoxon signed-rank test were used RESULTS: Twenty-four patients were enrolled. The mean age was 10.1 ± 5.8 years old and 75% male. All the patients had severe mental retardation and abnormal neurological examinations. A significant median percentual seizure frequency reduction was found: 68.12% (p = 0.05) at 1 week, 68.12% (p = 0.002) in the second week. We found no significant reduction at 1 and 2 months; mainly tonic and atonic seizures were reduced significantly at all times. Only mild self-limited side effects were recorded mainly itching and erythema in the application zone CONCLUSION: Ten sessions of c-tDCs in combination with pharmacologic treatment in LGS is safe and appears to reduce significatively tonic and atonic seizure frequency at 2 months of follow-up.
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Camacho‐Conde JA, Gonzalez‐Bermudez MDR, Carretero‐Rey M, Khan ZU. Brain stimulation: a therapeutic approach for the treatment of neurological disorders. CNS Neurosci Ther 2022; 28:5-18. [PMID: 34859593 PMCID: PMC8673710 DOI: 10.1111/cns.13769] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 10/28/2021] [Accepted: 11/09/2021] [Indexed: 01/14/2023] Open
Abstract
Brain stimulation has become one of the most acceptable therapeutic approaches in recent years and a powerful tool in the remedy against neurological diseases. Brain stimulation is achieved through the application of electric currents using non-invasive as well as invasive techniques. Recent technological advancements have evolved into the development of precise devices with capacity to produce well-controlled and effective brain stimulation. Currently, most used non-invasive techniques are repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS), whereas the most common invasive technique is deep brain stimulation (DBS). In last decade, application of these brain stimulation techniques has not only exploded but also expanded to wide variety of neurological disorders. Therefore, in the current review, we will provide an overview of the potential of both non-invasive (rTMS and tDCS) and invasive (DBS) brain stimulation techniques in the treatment of such brain diseases.
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Affiliation(s)
- Jose Antonio Camacho‐Conde
- Laboratory of NeurobiologyCIMESUniversity of MalagaMalagaSpain
- Department of MedicineFaculty of MedicineUniversity of MalagaMalagaSpain
| | | | - Marta Carretero‐Rey
- Laboratory of NeurobiologyCIMESUniversity of MalagaMalagaSpain
- Department of MedicineFaculty of MedicineUniversity of MalagaMalagaSpain
| | - Zafar U. Khan
- Laboratory of NeurobiologyCIMESUniversity of MalagaMalagaSpain
- Department of MedicineFaculty of MedicineUniversity of MalagaMalagaSpain
- CIBERNEDInstitute of Health Carlos IIIMadridSpain
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San-Juan D. Cathodal Transcranial Direct Current Stimulation in Refractory Epilepsy: A Noninvasive Neuromodulation Therapy. J Clin Neurophysiol 2021; 38:503-508. [PMID: 34261114 DOI: 10.1097/wnp.0000000000000717] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
SUMMARY Epilepsy is a chronic disease of the brain that affects individuals of all ages and has a worldwide distribution. According to a 2006 World Health Organization report, 50 million people had epilepsy. Approximately 30% of people with epilepsy have refractory disease despite recent therapeutic developments. Consequently, new treatments are necessary. Transcranial direct current stimulation (tDCS) is a noninvasive method for cortical excitability modulation by subthreshold membrane depolarization or hyperpolarization (cathodal stimulation decreases cortical excitability, whereas anodal stimulation increases it), which has been shown to be safe, economical, and easy to use. The mechanism of action of tDCS is partially understood. Cathodal tDCS in vitro and in vivo animal studies have shown that direct current and cathodal tDCS can successfully induce suppression of epileptiform activity in EEG recordings. Cathodal tDCS has been used in heterogeneous clinical trials in pediatric and adult patients with refractory epilepsy and is well tolerated. A comprehensive review of the clinical trials based on their quality and biases shows evidence that cathodal tDCS in patients with epilepsy is potentially effective. However, additional randomized clinical trials are needed with other etiologies, special populations, additional concomitants therapies, long-term follow-up, and new parameters of stimulation.
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Affiliation(s)
- Daniel San-Juan
- Clinical Neurophysiology Department, National Institute of Neurology and Neurosurgery, Mexico City, Mexico
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Kaufmann E, Hordt M, Lauseker M, Palm U, Noachtar S. Acute effects of spaced cathodal transcranial direct current stimulation in drug resistant focal epilepsies. Clin Neurophysiol 2021; 132:1444-1451. [PMID: 34023626 DOI: 10.1016/j.clinph.2021.03.048] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Revised: 02/28/2021] [Accepted: 03/13/2021] [Indexed: 01/04/2023]
Abstract
OBJECTIVE To evaluate the safety and temporal dynamic of the antiepileptic effect of spaced transcranial direct current stimulation (tDCS) in different focal epilepsies. METHODS Cathodal tDCS with individual electrode placement was performed in 15 adults with drug resistant focal epilepsy. An amplitude of 2 mA was applied twice for 9 minutes, with an interstimulation interval of 20 minutes. Tolerability was assessed via the Comfort Rating Questionnaire and the frequency of interictal epileptiform discharges (IEDs) was sequentially compared between the 24 hours before and after tDCS. RESULTS TDCS led to a significant reduction in the total number of IEDs/24 h by up to 68% (mean ± SD: -30.4 ± 21.1%, p = 0.001) as well as in seizure frequency (p = 0.041). The maximum IED reduction was observed between the 3rd and 21st hour after stimulation. Favorable clinical response was associated with structural etiology and clearly circumscribed epileptogenic foci but did not differ between frontal and temporal epilepsies. Overall, the tDCS treatment was well tolerated and did not lead to severe adverse events. CONCLUSIONS The spaced stimulation approach proved to be safe and well-tolerated in patients with drug-resistant unifocal epilepsies, leading to sustained IED and seizure frequency reduction. SIGNIFICANCE Spaced tDCS induces mediate antiepileptic effects with promising therapeutic potential.
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Affiliation(s)
- Elisabeth Kaufmann
- Epilepsy Center, Department of Neurology, University Hospital, LMU Munich, Munich, Germany.
| | - Mirjam Hordt
- Epilepsy Center, Department of Neurology, University Hospital, LMU Munich, Munich, Germany
| | - Michael Lauseker
- Institute for Medical Information Processing, Biometry, and Epidemiology, LMU Munich, Munich, Germany
| | - Ulrich Palm
- Department of Psychiatry and Psychotherapy, LMU Munich, Munich, Germany
| | - Soheyl Noachtar
- Epilepsy Center, Department of Neurology, University Hospital, LMU Munich, Munich, Germany
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Yang D, Shin YI, Hong KS. Systemic Review on Transcranial Electrical Stimulation Parameters and EEG/fNIRS Features for Brain Diseases. Front Neurosci 2021; 15:629323. [PMID: 33841079 PMCID: PMC8032955 DOI: 10.3389/fnins.2021.629323] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Accepted: 02/25/2021] [Indexed: 01/09/2023] Open
Abstract
Background Brain disorders are gradually becoming the leading cause of death worldwide. However, the lack of knowledge of brain disease’s underlying mechanisms and ineffective neuropharmacological therapy have led to further exploration of optimal treatments and brain monitoring techniques. Objective This study aims to review the current state of brain disorders, which utilize transcranial electrical stimulation (tES) and daily usable noninvasive neuroimaging techniques. Furthermore, the second goal of this study is to highlight available gaps and provide a comprehensive guideline for further investigation. Method A systematic search was conducted of the PubMed and Web of Science databases from January 2000 to October 2020 using relevant keywords. Electroencephalography (EEG) and functional near-infrared spectroscopy were selected as noninvasive neuroimaging modalities. Nine brain disorders were investigated in this study, including Alzheimer’s disease, depression, autism spectrum disorder, attention-deficit hyperactivity disorder, epilepsy, Parkinson’s disease, stroke, schizophrenia, and traumatic brain injury. Results Sixty-seven studies (1,385 participants) were included for quantitative analysis. Most of the articles (82.6%) employed transcranial direct current stimulation as an intervention method with modulation parameters of 1 mA intensity (47.2%) for 16–20 min (69.0%) duration of stimulation in a single session (36.8%). The frontal cortex (46.4%) and the cerebral cortex (47.8%) were used as a neuroimaging modality, with the power spectrum (45.7%) commonly extracted as a quantitative EEG feature. Conclusion An appropriate stimulation protocol applying tES as a therapy could be an effective treatment for cognitive and neurological brain disorders. However, the optimal tES criteria have not been defined; they vary across persons and disease types. Therefore, future work needs to investigate a closed-loop tES with monitoring by neuroimaging techniques to achieve personalized therapy for brain disorders.
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Affiliation(s)
- Dalin Yang
- School of Mechanical Engineering, Pusan National University, Busan, South Korea
| | - Yong-Il Shin
- Department of Rehabilitation Medicine, Pusan National University School of Medicine, Pusan National University Yangsan Hospital, Yangsan-si, South Korea
| | - Keum-Shik Hong
- Department of Rehabilitation Medicine, Pusan National University School of Medicine, Pusan National University Yangsan Hospital, Yangsan-si, South Korea
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Non-invasive cortical stimulation: Transcranial direct current stimulation (tDCS). INTERNATIONAL REVIEW OF NEUROBIOLOGY 2021; 159:1-22. [PMID: 34446242 DOI: 10.1016/bs.irn.2021.01.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Transcranial direct current stimulation (tDCS) is a re-emerging non-invasive brain stimulation technique that has been used in animal models and human trials aimed to elucidate neurophysiology and behavior interactions. It delivers subthreshold electrical currents to neuronal populations that shift resting membrane potential either toward depolarization or hyperpolarization, depending on stimulation parameters and neuronal orientation in relation to the induced electric field (EF). Although the resulting cerebral EFs are not strong enough to induce action potentials, spontaneous neuronal firing in response to inputs from other brain areas is influenced by tDCS. Additionally, tDCS induces plastic synaptic changes resembling long-term potentiation (LTP) or long-term depression (LTD) that outlast the period of stimulation. Such properties place tDCS as an appealing intervention for the treatment of diverse neuropsychiatric disorders. Although findings of clinical trials are preliminary for most studied conditions, there is already convincing evidence regarding its efficacy for unipolar depression. The main advantages of tDCS are the absence of serious or intolerable side effects and the portability of the devices, which might lead in the future to home-use applications and improved patient care. This chapter provides an up-to-date overview of a number tDCS relevant topics such as mechanisms of action, contemporary applications and safety. Furthermore, we propose ways to further develop tDCS research.
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Transcranial direct current stimulation (tDCS) in the management of epilepsy: A systematic review. Seizure 2021; 86:85-95. [PMID: 33582584 DOI: 10.1016/j.seizure.2021.01.020] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/22/2021] [Accepted: 01/30/2021] [Indexed: 12/22/2022] Open
Abstract
PURPOSE Current therapies for the management of epilepsy are still suboptimal for several patients due to inefficacy, major adverse events, and unavailability. Transcranial direct current stimulation (tDCS), an emergent non-invasive neuromodulation technique, has been tested in epilepsy samples over the past two decades to reduce either seizure frequency or electroencephalogram (EEG) epileptiform discharges. METHODS A systematic review was performed in accordance with PRISMA guidelines (PROSPERO record CRD42020160292). A thorough electronic search was completed in MEDLINE, EMBASE, CENTRAL and Scopus databases for trials that applied tDCS interventions to children and adults with epilepsy of any cause, from inception to April 30, 2020. RESULTS Twenty-seven studies fulfilled eligibility criteria, including nine sham-controlled and 18 uncontrolled trials or case reports/series. Samples consisted mainly of drug-resistant focal epilepsy patients that received cathodal tDCS stimulation targeted at the site with maximal EEG abnormalities. At follow-up, 84 % (21/25) of the included studies reported a reduction in seizure frequency and in 43 % (6/14) a decline in EEG epileptiform discharge rate was observed. No serious adverse events were reported. CONCLUSIONS Cathodal tDCS is both a safe and probably effective technique for seizure control in patients with drug-resistant focal epilepsy. However, published trials are heterogeneous regarding samples and methodology. More and larger sham-controlled randomized trials are needed, preferably with mechanistic informed stimulation protocols, to further advance tDCS therapy in the management of epilepsy.
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Buchanan DM, Bogdanowicz T, Khanna N, Lockman-Dufour G, Robaey P, D’Angiulli A. Systematic Review on the Safety and Tolerability of Transcranial Direct Current Stimulation in Children and Adolescents. Brain Sci 2021; 11:212. [PMID: 33578648 PMCID: PMC7916366 DOI: 10.3390/brainsci11020212] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/18/2021] [Accepted: 02/01/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Transcranial direct current stimulation (tDCS) is a safe, tolerable, and acceptable technique in adults. However, there is limited evidence for its safety in youth. Although limited, there are a handful of important empirical articles that have evaluated safety and tolerability outcomes in youth. However, a synthesis of pediatric safety studies is not currently available. OBJECTIVE To synthesize objective evidence regarding the safety and tolerability of pediatric tDCS based on the current state of the literature. METHODS Our search and report used PRISMA guidelines. Our method systematically examined investigations purposefully designed to evaluate the safety, tolerability, and acceptability of tDCS in healthy and atypical youth that were submitted to three databases, from the beginning of the database to November 2019. Safety considerations were evaluated by studies utilizing neuroimaging, physiological changes, performance on tasks, and by analyzing reported and objective side effects; tolerability via rate of adverse events; and acceptability via rate of dropouts. RESULTS We report on 203 sham sessions, 864 active sessions up to 2 mA, and 303 active hours of stimulation in 156 children. A total of 4.4% of the active sessions were in neurotypical controls, with the other 95.6% in clinical subjects. CONCLUSION In spite of the fact that the current evidence is sporadic and scarce, the presently reviewed literature provides support for the safety, tolerability, and acceptability, of tDCS in youth for 1-20 sessions of 20 min up to 2 mA. Future pediatric tDCS research is encouraged.
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Affiliation(s)
- Derrick Matthew Buchanan
- Department of Neuroscience, Carleton University, Ottawa, ON K1S 5B6, Canada; (T.B.); (N.K.); (G.L.-D.); (P.R.); (A.D.)
- Neuroscience of Imagination Cognition Emotion Research Lab, Carleton University, Ottawa, ON K1S 5B6, Canada
- Neuropsychiatric Lab, Children’s Hospital of Eastern Ontario, Ottawa, ON K1H 8L1, Canada
| | - Thomas Bogdanowicz
- Department of Neuroscience, Carleton University, Ottawa, ON K1S 5B6, Canada; (T.B.); (N.K.); (G.L.-D.); (P.R.); (A.D.)
- Neuroscience of Imagination Cognition Emotion Research Lab, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - Neha Khanna
- Department of Neuroscience, Carleton University, Ottawa, ON K1S 5B6, Canada; (T.B.); (N.K.); (G.L.-D.); (P.R.); (A.D.)
- Neuroscience of Imagination Cognition Emotion Research Lab, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - Guillaume Lockman-Dufour
- Department of Neuroscience, Carleton University, Ottawa, ON K1S 5B6, Canada; (T.B.); (N.K.); (G.L.-D.); (P.R.); (A.D.)
- Neuroscience of Imagination Cognition Emotion Research Lab, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - Philippe Robaey
- Department of Neuroscience, Carleton University, Ottawa, ON K1S 5B6, Canada; (T.B.); (N.K.); (G.L.-D.); (P.R.); (A.D.)
- Neuropsychiatric Lab, Children’s Hospital of Eastern Ontario, Ottawa, ON K1H 8L1, Canada
- Department of Psychiatry, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Amedeo D’Angiulli
- Department of Neuroscience, Carleton University, Ottawa, ON K1S 5B6, Canada; (T.B.); (N.K.); (G.L.-D.); (P.R.); (A.D.)
- Neuroscience of Imagination Cognition Emotion Research Lab, Carleton University, Ottawa, ON K1S 5B6, Canada
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13
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Sun Y, Dhamne SC, Carretero-Guillén A, Salvador R, Goldenberg MC, Godlewski BR, Pascual-Leone A, Madsen JR, Stone SSD, Ruffini G, Márquez-Ruiz J, Rotenberg A. Drug-Responsive Inhomogeneous Cortical Modulation by Direct Current Stimulation. Ann Neurol 2020; 88:489-502. [PMID: 32542794 PMCID: PMC10675838 DOI: 10.1002/ana.25822] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 06/11/2020] [Accepted: 06/12/2020] [Indexed: 12/15/2022]
Abstract
OBJECTIVE Cathodal direct current stimulation (cDCS) induces long-term depression (LTD)-like reduction of cortical excitability (DCS-LTD), which has been tested in the treatment of epilepsy with modest effects. In part, this may be due to variable cortical neuron orientation relative to the electric field. We tested, in vivo and in vitro, whether DCS-LTD occurs throughout the cortical thickness, and if not, then whether drug-DCS pairing can enhance the uniformity of the cortical response and the cDCS antiepileptic effect. METHODS cDCS-mediated changes in cortical excitability were measured in vitro in mouse motor cortex (M1) and in human postoperative neocortex, in vivo in mouse somatosensory cortex (S1), and in a mouse kainic acid (KA)-seizure model. Contributions of N-methyl-D-aspartate-type glutamate receptors (NMDARs) to cDCS-mediated plasticity were tested with application of NMDAR blockers (memantine/D-AP5). RESULTS cDCS reliably induced DCS-LTD in superficial cortical layers, and a long-term potentiation (LTP)-like enhancement (DCS-LTP) was recorded in deep cortical layers. Immunostaining confirmed layer-specific increase of phospho-S6 ribosomal protein in mouse M1. Similar nonuniform cDCS aftereffects on cortical excitability were also found in human neocortex in vitro and in S1 of alert mice in vivo. Application of memantine/D-AP5 either produced a more uniform DCS-LTD throughout the cortical thickness or at least abolished DCS-LTP. Moreover, a combination of memantine and cDCS suppressed KA-induced seizures. INTERPRETATION cDCS aftereffects are not uniform throughout cortical layers, which may explain the incomplete cDCS clinical efficacy. NMDAR antagonists may augment cDCS efficacy in epilepsy and other disorders where regional depression of cortical excitability is desirable. ANN NEUROL 2020;88:489-502.
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Affiliation(s)
- Yan Sun
- Department of Neurology and the F. M. Kirby Neurobiology Center, Boston, Massachusetts, USA
- Neuromodulation Program and Division of Epilepsy and Clinical Neurophysiology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Sameer C Dhamne
- Department of Neurology and the F. M. Kirby Neurobiology Center, Boston, Massachusetts, USA
- Neuromodulation Program and Division of Epilepsy and Clinical Neurophysiology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | | | | | - Marti C Goldenberg
- Department of Neurology and the F. M. Kirby Neurobiology Center, Boston, Massachusetts, USA
- Repository Core, Boston Children's Hospital, Boston, Massachusetts, USA
| | | | - Alvaro Pascual-Leone
- Berenson-Allen Center for Noninvasive Brain Stimulation, Division of Cognitive Neurology, Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
- Guttmann Institute, Autonomous University of Barcelona, Barcelona, Spain
| | - Joseph R Madsen
- Department of Neurosurgery, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Scellig S D Stone
- Department of Neurosurgery, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Giulio Ruffini
- Neuroelectrics Corporation, Cambridge, Massachusetts, USA
| | - Javier Márquez-Ruiz
- Department of Physiology, Anatomy and Cellular Biology, Pablo de Olavide University, Seville, Spain
| | - Alexander Rotenberg
- Department of Neurology and the F. M. Kirby Neurobiology Center, Boston, Massachusetts, USA
- Neuromodulation Program and Division of Epilepsy and Clinical Neurophysiology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
- Berenson-Allen Center for Noninvasive Brain Stimulation, Division of Cognitive Neurology, Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
- Guttmann Institute, Autonomous University of Barcelona, Barcelona, Spain
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14
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Wu YJ, Chien ME, Huang CH, Chiang CC, Lin CC, Huang CW, Durand DM, Hsu KS. Transcranial direct current stimulation alleviates seizure severity in kainic acid-induced status epilepticus rats. Exp Neurol 2020; 328:113264. [DOI: 10.1016/j.expneurol.2020.113264] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 02/28/2020] [Indexed: 12/20/2022]
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15
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Jung YJ, Lee YS, Choi GY, Hwang HJ. Development of a transcranial direct current stimulation device based on current limiter for simultaneous measurement of electroencephalography: A feasibility study. Technol Health Care 2020; 28:123-130. [PMID: 32333570 PMCID: PMC7369038 DOI: 10.3233/thc-209013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND: Electroencephalography (EEG) measured during transcranial direct current stimulation (tDCS) can help understand the accurate impact of tDCS on the brain, but this has been hindered due to significant inflow of tDCS-induced electrical artifacts. OBJECTIVE: In this study, we introduce a novel tDCS device developed based on current limiter, which can prevent the generation of significant electrical artifacts. METHODS: To verify the feasibility of our developed tDCS device, we performed simultaneous measurement of EEG during tDCS application with five different current intensities (0, 500, 1,000, 1,500, and 2,000 μA). Changes in EEG power spectral density (PSD) and correlation between the PSD of non-stimulation and tDCS condition were investigated to see whether our tDCS device can be used for simultaneous EEG recording without significant inflow of tDCS-induced electrical artifacts. RESUTLS: The mean EEG-PSD differences between non-stimulation and tDCS condition were not significant for all stimulation current intensities. Furthermore, EEG-PSDs estimated during non-stimulation and tDCS application showed statistically high correlation for all comparison cases. CONCLUSION: Based on the results, we could demonstrate the feasibility of our tDCS device based on current limiter for simultaneous EEG measurement, which could potentially provide a way to investigate the impact of tDCS on the brain more accurately.
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Affiliation(s)
- Young-Jin Jung
- Department of Radiological Science, Dongseo University, Busan, Korea.,Center for Radiological Environment and Health Science, Dongseo University, Busan, Korea
| | - Yun-Sung Lee
- Department of Electronics and Information Engineering, Korea University, Sejong, Korea
| | - Ga-Young Choi
- Department of Electronics and Information Engineering, Korea University, Sejong, Korea
| | - Han-Jeong Hwang
- Department of Electronics and Information Engineering, Korea University, Sejong, Korea
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16
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Lazarev V, Gebodh N, Tamborino T, Bikson M, Caparelli-Daquer E. Experimental-design Specific Changes in Spontaneous EEG and During Intermittent Photic Stimulation by High Definition Transcranial Direct Current Stimulation. Neuroscience 2020; 426:50-58. [DOI: 10.1016/j.neuroscience.2019.11.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Revised: 10/24/2019] [Accepted: 11/11/2019] [Indexed: 01/30/2023]
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17
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Starnes K, Miller K, Wong-Kisiel L, Lundstrom BN. A Review of Neurostimulation for Epilepsy in Pediatrics. Brain Sci 2019; 9:brainsci9100283. [PMID: 31635298 PMCID: PMC6826633 DOI: 10.3390/brainsci9100283] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 10/14/2019] [Accepted: 10/17/2019] [Indexed: 12/16/2022] Open
Abstract
Neurostimulation for epilepsy refers to the application of electricity to affect the central nervous system, with the goal of reducing seizure frequency and severity. We review the available evidence for the use of neurostimulation to treat pediatric epilepsy, including vagus nerve stimulation (VNS), responsive neurostimulation (RNS), deep brain stimulation (DBS), chronic subthreshold cortical stimulation (CSCS), transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS). We consider possible mechanisms of action and safety concerns, and we propose a methodology for selecting between available options. In general, we find neurostimulation is safe and effective, although any high quality evidence applying neurostimulation to pediatrics is lacking. Further research is needed to understand neuromodulatory systems, and to identify biomarkers of response in order to establish optimal stimulation paradigms.
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Affiliation(s)
- Keith Starnes
- Department of Neurology, Mayo Clinic, Rochester, MN 55905, USA.
| | - Kai Miller
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN 55905, USA.
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18
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Valdés-Cruz A, Villasana-Salazar B, Williams B, Martínez-Vargas D, Magdaleno-Madrigal VM, Almazán-Alvarado S, Besio WG. Transcranial focal electrical stimulation via concentric ring electrodes in freely moving cats: Antiepileptogenic and postictal effects. Exp Neurol 2019; 320:113012. [DOI: 10.1016/j.expneurol.2019.113012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 06/26/2019] [Accepted: 07/09/2019] [Indexed: 01/13/2023]
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19
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Almquist JNF, Mathan S, Brem AK, Plessow F, McKanna J, Santarnecchi E, Pascual-Leone A, Cohen Kadosh R, Pavel M, Yeung N. FAST: A Novel, Executive Function-Based Approach to Cognitive Enhancement. Front Hum Neurosci 2019; 13:235. [PMID: 31427935 PMCID: PMC6687878 DOI: 10.3389/fnhum.2019.00235] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 06/25/2019] [Indexed: 12/03/2022] Open
Abstract
The present study introduces a novel cognitive intervention aimed at improving fluid intelligence (Gf), based on a framework we refer to as FAST: Flexible, Adaptive, Synergistic Training. FAST leverages a combination of novel game-based executive function (EF) training—designed specifically to enhance the likelihood of transfer—and transcranial electrical stimulation (tES), with aims to synergistically activate and strengthen mechanisms of cognitive control critical to Gf. To test our intervention, we collected three Gf measures from 113 participants [the advanced short Bochumer Matrizen-Test (BOMAT), Raven’s Advanced Progressive Matrices (APM), and matrices similar to Raven’s generated by Sandia labs], prior to and following one of three interventions: (1) the FAST + tRNS intervention, a combination of 30 min of daily training with our novel training game, Robot Factory, and 20 min of concurrent transcranial random noise stimulation applied to bilateral dorsolateral prefrontal cortex (DLPFC); (2) an adaptively difficult Active Control intervention comprised of visuospatial tasks that specifically do not target Gf; or (3) a no-contact control condition. Analyses of changes in a Gf factor from pre- to post-test found numerical increases for the FAST + tRNS group compared to the two control conditions, with a 0.3 SD increase relative to Active Control (p = 0.07), and a 0.19 SD increase relative to a No-contact control condition (p = 0.26). This increase was found to be largely driven by significant differences in pre- and post-test Gf as measured on the BOMAT test. Progression through the FAST training game (Robot Factory) was significantly correlated with changes in Gf. This is in contrast with progress in the Active Control condition, as well as with changes in individual EFs during FAST training, which did not significantly correlate with changes in Gf. Taken together, this research represents a useful step forward in providing new insights into, and new methods for studying, the nature of Gf and its malleability. Though our results await replication and extension, they provide preliminary evidence that the crucial characteristic of Gf may, in fact, be the ability to combine EFs rapidly and adaptively according to changing demand, and that Gf may be susceptible to targeted training.
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Affiliation(s)
| | - Santosh Mathan
- Honeywell Labs, Honeywell Aerospace, Redmond, WA, United States
| | - Anna-Katharine Brem
- Department of Neurology, Berenson-Allen Center for Non-Invasive Brain Stimulation, Beth Israel Deaconess Medical Center, Division for Cognitive Neurology, Harvard Medical School, Boston, MA, United States.,Department of Experimental Psychology, Medical Sciences Division, University of Oxford, Oxford, United Kingdom
| | - Franziska Plessow
- Department of Neurology, Berenson-Allen Center for Non-Invasive Brain Stimulation, Beth Israel Deaconess Medical Center, Division for Cognitive Neurology, Harvard Medical School, Boston, MA, United States
| | - James McKanna
- Department of Electrical and Computer Engineering, Northeastern University, Boston, MA, United States
| | - Emiliano Santarnecchi
- Department of Neurology, Berenson-Allen Center for Non-Invasive Brain Stimulation, Beth Israel Deaconess Medical Center, Division for Cognitive Neurology, Harvard Medical School, Boston, MA, United States
| | - Alvaro Pascual-Leone
- Department of Neurology, Berenson-Allen Center for Non-Invasive Brain Stimulation, Beth Israel Deaconess Medical Center, Division for Cognitive Neurology, Harvard Medical School, Boston, MA, United States
| | - Roi Cohen Kadosh
- Department of Experimental Psychology, Medical Sciences Division, University of Oxford, Oxford, United Kingdom
| | - Misha Pavel
- Department of Electrical and Computer Engineering, Northeastern University, Boston, MA, United States
| | - Nick Yeung
- Department of Experimental Psychology, Medical Sciences Division, University of Oxford, Oxford, United Kingdom
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20
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Gebodh N, Esmaeilpour Z, Adair D, Chelette K, Dmochowski J, Woods AJ, Kappenman ES, Parra LC, Bikson M. Inherent physiological artifacts in EEG during tDCS. Neuroimage 2018; 185:408-424. [PMID: 30321643 DOI: 10.1016/j.neuroimage.2018.10.025] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 09/10/2018] [Accepted: 10/08/2018] [Indexed: 12/30/2022] Open
Abstract
Online imaging and neuromodulation is invalid if stimulation distorts measurements beyond the point of accurate measurement. In theory, combining transcranial Direct Current Stimulation (tDCS) with electroencephalography (EEG) is compelling, as both use non-invasive electrodes and image-guided dose can be informed by the reciprocity principle. To distinguish real changes in EEG from stimulation artifacts, prior studies applied conventional signal processing techniques (e.g. high-pass filtering, ICA). Here, we address the assumptions underlying the suitability of these approaches. We distinguish physiological artifacts - defined as artifacts resulting from interactions between the stimulation induced voltage and the body and so inherent regardless of tDCS or EEG hardware performance - from methodology-related artifacts - arising from non-ideal experimental conditions or non-ideal stimulation and recording equipment performance. Critically, we identify inherent physiological artifacts which are present in all online EEG-tDCS: 1) cardiac distortion and 2) ocular motor distortion. In conjunction, non-inherent physiological artifacts which can be minimized in most experimental conditions include: 1) motion and 2) myogenic distortion. Artifact dynamics were analyzed for varying stimulation parameters (montage, polarity, current) and stimulation hardware. Together with concurrent physiological monitoring (ECG, respiration, ocular, EMG, head motion), and current flow modeling, each physiological artifact was explained by biological source-specific body impedance changes, leading to incremental changes in scalp DC voltage that are significantly larger than real neural signals. Because these artifacts modulate the DC voltage and scale with applied current, they are dose specific such that their contamination cannot be accounted for by conventional experimental controls (e.g. differing stimulation montage or current as a control). Moreover, because the EEG artifacts introduced by physiologic processes during tDCS are high dimensional (as indicated by Generalized Singular Value Decomposition- GSVD), non-stationary, and overlap highly with neurogenic frequencies, these artifacts cannot be easily removed with conventional signal processing techniques. Spatial filtering techniques (GSVD) suggest that the removal of physiological artifacts would significantly degrade signal integrity. Physiological artifacts, as defined here, would emerge only during tDCS, thus processing techniques typically applied to EEG in the absence of tDCS would not be suitable for artifact removal during tDCS. All concurrent EEG-tDCS must account for physiological artifacts that are a) present regardless of equipment used, and b) broadband and confound a broad range of experiments (e.g. oscillatory activity and event related potentials). Removal of these artifacts requires the recognition of their non-stationary, physiology-specific dynamics, and individualized nature. We present a broad taxonomy of artifacts (non/stimulation related), and suggest possible approaches and challenges to denoising online EEG-tDCS stimulation artifacts.
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Affiliation(s)
- Nigel Gebodh
- Neural Engineering Laboratory, Department of Biomedical Engineering, The City College of New York of the City University of New York, New York, NY, USA.
| | - Zeinab Esmaeilpour
- Neural Engineering Laboratory, Department of Biomedical Engineering, The City College of New York of the City University of New York, New York, NY, USA.
| | - Devin Adair
- Department of Psychology, The Graduate Center at City University of New York, New York, NY, USA.
| | | | - Jacek Dmochowski
- Neural Engineering Laboratory, Department of Biomedical Engineering, The City College of New York of the City University of New York, New York, NY, USA.
| | - Adam J Woods
- Center for Cognitive Aging and Memory, McKnight Brain Institute, Department of Clinical and Health Psychology, Department of Neuroscience, University of Florida, Gainesville, FL, USA.
| | | | - Lucas C Parra
- Neural Engineering Laboratory, Department of Biomedical Engineering, The City College of New York of the City University of New York, New York, NY, USA.
| | - Marom Bikson
- Neural Engineering Laboratory, Department of Biomedical Engineering, The City College of New York of the City University of New York, New York, NY, USA; Department of Psychology, The Graduate Center at City University of New York, New York, NY, USA.
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21
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Doruk Camsari D, Kirkovski M, Croarkin PE. Therapeutic Applications of Noninvasive Neuromodulation in Children and Adolescents. Psychiatr Clin North Am 2018; 41:465-477. [PMID: 30098658 PMCID: PMC6413505 DOI: 10.1016/j.psc.2018.05.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Recent advances and growing evidence supporting the safety and efficacy of noninvasive neuromodulatory techniques in adults have facilitated the study of neuromodulation applications in children and adolescents. Noninvasive brain stimulation methods such as transcranial direct current stimulation and transcranial magnetic stimulation have been considered in children with depression, autism spectrum disorder, attention-deficit hyperactivity disorder, and other neuropsychiatric disorders. However, current clinical applications of neuromodulation techniques in children and adolescents are nascent. There is a great need for developmentally informed, large, double-blinded, randomized, controlled clinical trials to demonstrate efficacy and safety of noninvasive brain stimulation in children and adolescents.
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Affiliation(s)
- Deniz Doruk Camsari
- Department of Psychiatry and Psychology, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA
| | - Melissa Kirkovski
- Deakin Child Study Centre, School of Psychology, Deakin University, Geelong, VIC 3220, Australia
| | - Paul E Croarkin
- Department of Psychiatry and Psychology, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA.
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22
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Falcone B, Wada A, Parasuraman R, Callan DE. Individual differences in learning correlate with modulation of brain activity induced by transcranial direct current stimulation. PLoS One 2018; 13:e0197192. [PMID: 29782510 PMCID: PMC5962315 DOI: 10.1371/journal.pone.0197192] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 04/27/2018] [Indexed: 12/16/2022] Open
Abstract
Transcranial direct current stimulation (tDCS) has been shown to enhance cognitive performance on a variety of tasks. It is hypothesized that tDCS enhances performance by affecting task related cortical excitability changes in networks underlying or connected to the site of stimulation facilitating long term potentiation. However, many recent studies have called into question the reliability and efficacy of tDCS to induce modulatory changes in brain activity. In this study, our goal is to investigate the individual differences in tDCS induced modulatory effects on brain activity related to the degree of enhancement in performance, providing insight into this lack of reliability. In accomplishing this goal, we used functional magnetic resonance imaging (fMRI) concurrently with tDCS stimulation (1 mA, 30 minutes duration) using a visual search task simulating real world conditions. The experiment consisted of three fMRI sessions: pre-training (no performance feedback), training (performance feedback which included response accuracy and target location and either real tDCS or sham stimulation given), and post-training (no performance feedback). The right posterior parietal cortex was selected as the site of anodal tDCS based on its known role in visual search and spatial attention processing. Our results identified a region in the right precentral gyrus, known to be involved with visual spatial attention and orienting, that showed tDCS induced task related changes in cortical excitability that were associated with individual differences in improved performance. This same region showed greater activity during the training session for target feedback of incorrect (target-error feedback) over correct trials for the tDCS stim over sham group indicating greater attention to target features during training feedback when trials were incorrect. These results give important insight into the nature of neural excitability induced by tDCS as it relates to variability in individual differences in improved performance shedding some light the apparent lack of reliability found in tDCS research.
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Affiliation(s)
- Brian Falcone
- Center of Excellence in Neuroergonomics, Technology, and Cognition (CENTEC), George Mason University, Fairfax, Virginia, United States of America
| | - Atsushi Wada
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology (NICT), Osaka University, Osaka, Japan
| | - Raja Parasuraman
- Center of Excellence in Neuroergonomics, Technology, and Cognition (CENTEC), George Mason University, Fairfax, Virginia, United States of America
| | - Daniel E. Callan
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology (NICT), Osaka University, Osaka, Japan
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23
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Varoli E, Pisoni A, Mattavelli GC, Vergallito A, Gallucci A, Mauro LD, Rosanova M, Bolognini N, Vallar G, Romero Lauro LJ. Tracking the Effect of Cathodal Transcranial Direct Current Stimulation on Cortical Excitability and Connectivity by Means of TMS-EEG. Front Neurosci 2018; 12:319. [PMID: 29867330 PMCID: PMC5962888 DOI: 10.3389/fnins.2018.00319] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 04/24/2018] [Indexed: 12/23/2022] Open
Abstract
Transcranial direct current stimulation (tDCS) is increasingly used in both research and therapeutic settings, but its precise mechanisms remain largely unknown. At a neuronal level, tDCS modulates cortical excitability by shifting the resting membrane potential in a polarity-dependent way: anodal stimulation increases the spontaneous firing rate, while cathodal decreases it. However, the neurophysiological underpinnings of anodal/cathodal tDCS seem to be different, as well as their behavioral effect, in particular when high order areas are involved, compared to when motor or sensory brain areas are targeted. Previously, we investigated the effect of anodal tDCS on cortical excitability, by means of a combination of Transcranial Magnetic Stimulation (TMS) and Electroencephalography (EEG). Results showed a diffuse rise of cortical excitability in a bilateral fronto-parietal network. In the present study, we tested, with the same paradigm, the effect of cathodal tDCS. Single pulse TMS was delivered over the left posterior parietal cortex (PPC), before, during, and after 10 min of cathodal or sham tDCS over the right PPC, while recording HD-EEG. Indexes of global and local cortical excitability were obtained both at sensors and cortical sources level. At sensors, global and local mean field power (GMFP and LMFP) were computed for three temporal windows (0-50, 50-100, and 100-150 ms), on all channels (GMFP), and in four different clusters of electrodes (LMFP, left and right, in frontal and parietal regions). After source reconstruction, Significant Current Density was computed at the global level, and for four Broadmann's areas (left/right BA 6 and 7). Both sensors and cortical sources results converge in showing no differences during and after cathodal tDCS compared to pre-stimulation sessions, both at global and local level. The same holds for sham tDCS. These data highlight an asymmetric impact of anodal and cathodal stimulation on cortical excitability, with a diffuse effect of anodal and no effect of cathodal tDCS over the parietal cortex. These results are consistent with the current literature: while anodal-excitatory and cathodal-inhibitory effects are well-established in the sensory and motor domains, both at physiological and behavioral levels, results for cathodal stimulation are more controversial for modulation of exitability of higher order areas.
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Affiliation(s)
- Erica Varoli
- Ph.D. Program in Neuroscience, Department of Medicine and Surgery, University Milano-Bicocca, Monza, Italy.,NeuroMi - Milan Center of Neuroscience, Milan, Italy
| | - Alberto Pisoni
- NeuroMi - Milan Center of Neuroscience, Milan, Italy.,Department of Psychology, University of Milano-Bicocca, Milan, Italy
| | - Giulia C Mattavelli
- NeuroMi - Milan Center of Neuroscience, Milan, Italy.,Department of Psychology, University of Milano-Bicocca, Milan, Italy
| | - Alessandra Vergallito
- NeuroMi - Milan Center of Neuroscience, Milan, Italy.,Department of Psychology, University of Milano-Bicocca, Milan, Italy
| | - Alessia Gallucci
- Department of Psychology, University of Milano-Bicocca, Milan, Italy
| | - Lilia D Mauro
- Department of Psychology, University of Milano-Bicocca, Milan, Italy
| | - Mario Rosanova
- Department of Biomedical and Clinical Sciences "L. Sacco", University of Milan, Milan, Italy.,Fondazione Europea per la Ricerca Biomedica Onlus, Milan, Italy
| | - Nadia Bolognini
- NeuroMi - Milan Center of Neuroscience, Milan, Italy.,Department of Psychology, University of Milano-Bicocca, Milan, Italy.,Laboratory of Neuropsychology, IRCCS Istituto Auxologico, Milan, Italy
| | - Giuseppe Vallar
- NeuroMi - Milan Center of Neuroscience, Milan, Italy.,Department of Psychology, University of Milano-Bicocca, Milan, Italy.,Laboratory of Neuropsychology, IRCCS Istituto Auxologico, Milan, Italy
| | - Leonor J Romero Lauro
- NeuroMi - Milan Center of Neuroscience, Milan, Italy.,Department of Psychology, University of Milano-Bicocca, Milan, Italy
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24
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Regner GG, Pereira P, Leffa DT, de Oliveira C, Vercelino R, Fregni F, Torres ILS. Preclinical to Clinical Translation of Studies of Transcranial Direct-Current Stimulation in the Treatment of Epilepsy: A Systematic Review. Front Neurosci 2018; 12:189. [PMID: 29623027 PMCID: PMC5874505 DOI: 10.3389/fnins.2018.00189] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 03/08/2018] [Indexed: 12/09/2022] Open
Abstract
Epilepsy is a chronic brain syndrome characterized by recurrent seizures resulting from excessive neuronal discharges. Despite the development of various new antiepileptic drugs, many patients are refractory to treatment and report side effects. Non-invasive methods of brain stimulation, such as transcranial direct current stimulation (tDCS), have been tested as alternative approaches to directly modulate the excitability of epileptogenic neural circuits. Although some pilot and initial clinical studies have shown positive results, there is still uncertainty regarding the next steps of investigation in this field. Therefore, we reviewed preclinical and clinical studies using the following framework: (1) preclinical studies that have been successfully translated to clinical studies, (2) preclinical studies that have failed to be translated to clinical studies, and (3) clinical findings that were not previously tested in preclinical studies. We searched PubMed, Web of Science, Embase, and SciELO (2002–2017) using the keywords “tDCS,” “epilepsy,” “clinical trials,” and “animal models.” Our initial search resulted in 64 articles. After applying inclusion and exclusion criteria, we screened 17 full-text articles to extract findings about the efficacy of tDCS, with respect to the therapeutic framework used and the resulting reduction in seizures and epileptiform patterns. We found that few preclinical findings have been translated into clinical research (number of sessions and effects on seizure frequency) and that most findings have not been tested clinically (effects of tDCS on status epilepticus and absence epilepsy, neuroprotective effects in the hippocampus, and combined use with specific medications). Finally, considering that clinical studies on tDCS have been conducted for several epileptic syndromes, most were not previously tested in preclinical studies (Rasmussen's encephalitis, drug resistant epilepsy, and hippocampal sclerosis-induced epilepsy). Overall, most studies report positive findings. However, it is important to underscore that a successful preclinical study may not indicate success in a clinical study, considering the differences highlighted herein. Although most studies report significant findings, there are still important insights from preclinical work that must be tested clinically. Understanding these factors may improve the evidence for the potential use of this technique as a clinical tool in the treatment of epilepsy.
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Affiliation(s)
- Gabriela G Regner
- Laboratory of Neuropharmacology and Preclinical Toxicology, Institute of Basic Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Laboratory of Pain Pharmacology and Neuromodulation, Preclinical Studies - Pharmacology Department, Institute of Basic Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Postgraduate Program in Biological Sciences, Pharmacology and Therapeutics, Institute of Basic Health Sciences, Universidade Federal Rio Grande do Sul, Porto Alegre, Brazil
| | - Patrícia Pereira
- Laboratory of Neuropharmacology and Preclinical Toxicology, Institute of Basic Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Postgraduate Program in Biological Sciences, Pharmacology and Therapeutics, Institute of Basic Health Sciences, Universidade Federal Rio Grande do Sul, Porto Alegre, Brazil
| | - Douglas T Leffa
- Laboratory of Pain Pharmacology and Neuromodulation, Preclinical Studies - Pharmacology Department, Institute of Basic Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Postgraduate Program in Medical Sciences, School of Medicine Universidade Federal Rio Grande do Sul, Porto Alegre, Brazil
| | - Carla de Oliveira
- Laboratory of Pain Pharmacology and Neuromodulation, Preclinical Studies - Pharmacology Department, Institute of Basic Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Postgraduate Program in Medical Sciences, School of Medicine Universidade Federal Rio Grande do Sul, Porto Alegre, Brazil
| | - Rafael Vercelino
- Laboratory of Pain Pharmacology and Neuromodulation, Preclinical Studies - Pharmacology Department, Institute of Basic Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Centro Universitário FADERGS, Health and Wellness School Laureate International Universities, Porto Alegre, Brazil
| | - Felipe Fregni
- Laboratory of Neuromodulation, Department of Physical Medicine & Rehabilitation, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard University, Boston, MA, United States
| | - Iraci L S Torres
- Laboratory of Pain Pharmacology and Neuromodulation, Preclinical Studies - Pharmacology Department, Institute of Basic Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Postgraduate Program in Biological Sciences, Pharmacology and Therapeutics, Institute of Basic Health Sciences, Universidade Federal Rio Grande do Sul, Porto Alegre, Brazil.,Postgraduate Program in Medical Sciences, School of Medicine Universidade Federal Rio Grande do Sul, Porto Alegre, Brazil
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25
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Bikson M, Paneri B, Mourdoukoutas A, Esmaeilpour Z, Badran BW, Azzam R, Adair D, Datta A, Fang XH, Wingeier B, Chao D, Alonso-Alonso M, Lee K, Knotkova H, Woods AJ, Hagedorn D, Jeffery D, Giordano J, Tyler WJ. Limited output transcranial electrical stimulation (LOTES-2017): Engineering principles, regulatory statutes, and industry standards for wellness, over-the-counter, or prescription devices with low risk. Brain Stimul 2017; 11:134-157. [PMID: 29122535 DOI: 10.1016/j.brs.2017.10.012] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 09/16/2017] [Accepted: 10/15/2017] [Indexed: 01/17/2023] Open
Abstract
We present device standards for low-power non-invasive electrical brain stimulation devices classified as limited output transcranial electrical stimulation (tES). Emerging applications of limited output tES to modulate brain function span techniques to stimulate brain or nerve structures, including transcranial direct current stimulation (tDCS), transcranial alternating current stimulation (tACS), and transcranial pulsed current stimulation (tPCS), have engendered discussion on how access to technology should be regulated. In regards to legal regulations and manufacturing standards for comparable technologies, a comprehensive framework already exists, including quality systems (QS), risk management, and (inter)national electrotechnical standards (IEC). In Part 1, relevant statutes are described for medical and wellness application. While agencies overseeing medical devices have broad jurisdiction, enforcement typically focuses on those devices with medical claims or posing significant risk. Consumer protections regarding responsible marketing and manufacture apply regardless. In Part 2 of this paper, we classify the electrical output performance of devices cleared by the United States Food and Drug Administration (FDA) including over-the-counter (OTC) and prescription electrostimulation devices, devices available for therapeutic or cosmetic purposes, and devices indicated for stimulation of the body or head. Examples include iontophoresis devices, powered muscle stimulators (PMS), cranial electrotherapy stimulation (CES), and transcutaneous electrical nerve stimulation (TENS) devices. Spanning over 13 FDA product codes, more than 1200 electrical stimulators have been cleared for marketing since 1977. The output characteristics of conventional tDCS, tACS, and tPCS techniques are well below those of most FDA cleared devices, including devices that are available OTC and those intended for stimulation on the head. This engineering analysis demonstrates that with regard to output performance and standing regulation, the availability of tDCS, tACS, or tPCS to the public would not introduce risk, provided such devices are responsibly manufactured and legally marketed. In Part 3, we develop voluntary manufacturer guidance for limited output tES that is aligned with current regulatory standards. Based on established medical engineering and scientific principles, we outline a robust and transparent technical framework for ensuring limited output tES devices are designed to minimize risks, while also supporting access and innovation. Alongside applicable medical and government activities, this voluntary industry standard (LOTES-2017) further serves an important role in supporting informed decisions by the public.
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Affiliation(s)
- Marom Bikson
- The City College of New York, Department of Biomedical Engineering, New York, NY 10031, USA.
| | - Bhaskar Paneri
- The City College of New York, Department of Biomedical Engineering, New York, NY 10031, USA
| | - Andoni Mourdoukoutas
- The City College of New York, Department of Biomedical Engineering, New York, NY 10031, USA
| | - Zeinab Esmaeilpour
- The City College of New York, Department of Biomedical Engineering, New York, NY 10031, USA
| | - Bashar W Badran
- U.S. Army Research Laboratory, Aberdeen Proving Ground, MD, USA; Department of Psychology, University of New Mexico, Albuquerque, NM, USA
| | | | - Devin Adair
- The City College of New York, Department of Biomedical Engineering, New York, NY 10031, USA
| | | | - Xiao Hui Fang
- The City College of New York, Department of Biomedical Engineering, New York, NY 10031, USA
| | | | - Daniel Chao
- Halo Neuroscience Inc., San Francisco, CA 94103, USA
| | - Miguel Alonso-Alonso
- Harvard Medical School, Berenson-Allen Center for Noninvasive Brain Stimulation, Division of Cognitive Neurology, Boston, MA, USA
| | - Kiwon Lee
- Ybrain Inc., Sampyeong-dong, Seongnam-si, South Korea
| | - Helena Knotkova
- MJHS Institute for Innovation in Palliative Care, New York, NY, USA; Department of Family and Social Medicine, Albert Einstein College of Medicine, The Bronx, NY, USA
| | - Adam J Woods
- Center for Cognitive Aging and Memory, McKnight Brain Institute, Department of Clinical and Health Psychology, University of Florida, USA
| | | | | | - James Giordano
- Department of Neurology and Neuroethics Studies Program, Pellegrino Center for Clinical Bioethics, Georgetown University Medical Center, Washington, DC, USA
| | - William J Tyler
- Arizona State University, School of Biological and Health Systems Engineering, Tempe, AZ 85287, USA
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26
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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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27
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Abstract
The revolution in theory, swift technological developments, and invention of new devices have driven tremendous progress in neurostimulation as a third‐line treatment for epilepsy. Over the past decades, neurostimulation took its place in the field of epilepsy as an advanced treatment technique and opened up a new world. Numerous animal studies have proven the physical efficacy of stimulation of the brain and peripheral nerves. Based on this optimistic fundamental research, new advanced techniques are being explored in clinical practice. Over the past century, drawing on the benefits brought about by vagus nerve stimulation for the treatment of epilepsy, various new neurostimulation modalities have been developed to control seizures. Clinical studies including case reports, case series, and clinical trials have been booming in the past several years. This article gives a comprehensive review of most of these clinical studies. In addition to highlighting the advantages of neurostimulation for the treatment of epilepsy, concerns with this modality and future development directions are also discussed. The biggest advantage of neurostimulation over pharmacological treatments for epilepsy is the modulation of the epilepsy network by delivering stimuli at a specific target or the “hub.” Conversely, however, a lack of knowledge of epilepsy networks and the mechanisms of neurostimulation may hinder further development. Therefore, theoretical research on the mechanism of epileptogenesis and epilepsy networks is needed in the future. Within the multiple modalities of neuromodulation, the final choice should be made after full discussion with a multidisciplinary team at a presurgical conference. Furthermore, the establishment of a neurostimulation system with standardized parameters and rigorous guidelines is another important issue. To achieve this goal, a worldwide collaboration of epilepsy centers is also suggested in the future.
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Affiliation(s)
- Yicong Lin
- Department of Neurology Xuanwu Hospital Capital Medical University Beijing China.,Beijing Key Laboratory of Neuromodulation Beijing China.,Center of Epilepsy Beijing Institute for Brain Disorders Capital Medical University Beijing China
| | - Yuping Wang
- Department of Neurology Xuanwu Hospital Capital Medical University Beijing China.,Beijing Key Laboratory of Neuromodulation Beijing China.,Center of Epilepsy Beijing Institute for Brain Disorders Capital Medical University Beijing China
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28
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Dmochowski JP, Koessler L, Norcia AM, Bikson M, Parra LC. Optimal use of EEG recordings to target active brain areas with transcranial electrical stimulation. Neuroimage 2017; 157:69-80. [PMID: 28578130 PMCID: PMC5777160 DOI: 10.1016/j.neuroimage.2017.05.059] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 05/11/2017] [Accepted: 05/27/2017] [Indexed: 12/14/2022] Open
Abstract
To demonstrate causal relationships between brain and behavior, investigators would like to guide brain stimulation using measurements of neural activity. Particularly promising in this context are electroencephalography (EEG) and transcranial electrical stimulation (TES), as they are linked by a reciprocity principle which, despite being known for decades, has not led to a formalism for relating EEG recordings to optimal stimulation parameters. Here we derive a closed-form expression for the TES configuration that optimally stimulates (i.e., targets) the sources of recorded EEG, without making assumptions about source location or distribution. We also derive a duality between TES targeting and EEG source localization, and demonstrate that in cases where source localization fails, so does the proposed targeting. Numerical simulations with multiple head models confirm these theoretical predictions and quantify the achieved stimulation in terms of focality and intensity. We show that constraining the stimulation currents automatically selects optimal montages that involve only a few (4-7) electrodes, with only incremental loss in performance when targeting focal activations. The proposed technique allows brain scientists and clinicians to rationally target the sources of observed EEG and thus overcomes a major obstacle to the realization of individualized or closed-loop brain stimulation.
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Affiliation(s)
- Jacek P Dmochowski
- Department of Biomedical Engineering, Steinman Hall 460 City College of New York, New York, NY 10031, USA.
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29
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Giovanni A, Capone F, di Biase L, Ferreri F, Florio L, Guerra A, Marano M, Paolucci M, Ranieri F, Salomone G, Tombini M, Thut G, Di Lazzaro V. Oscillatory Activities in Neurological Disorders of Elderly: Biomarkers to Target for Neuromodulation. Front Aging Neurosci 2017; 9:189. [PMID: 28659788 PMCID: PMC5468377 DOI: 10.3389/fnagi.2017.00189] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 05/26/2017] [Indexed: 12/13/2022] Open
Abstract
Non-invasive brain stimulation (NIBS) has been under investigation as adjunct treatment of various neurological disorders with variable success. One challenge is the limited knowledge on what would be effective neuronal targets for an intervention, combined with limited knowledge on the neuronal mechanisms of NIBS. Motivated on the one hand by recent evidence that oscillatory activities in neural systems play a role in orchestrating brain functions and dysfunctions, in particular those of neurological disorders specific of elderly patients, and on the other hand that NIBS techniques may be used to interact with these brain oscillations in a controlled way, we here explore the potential of modulating brain oscillations as an effective strategy for clinical NIBS interventions. We first review the evidence for abnormal oscillatory profiles to be associated with a range of neurological disorders of elderly (e.g., Parkinson's disease (PD), Alzheimer's disease (AD), stroke, epilepsy), and for these signals of abnormal network activity to normalize with treatment, and/or to be predictive of disease progression or recovery. We then ask the question to what extent existing NIBS protocols have been tailored to interact with these oscillations and possibly associated dysfunctions. Our review shows that, despite evidence for both reliable neurophysiological markers of specific oscillatory dis-functionalities in neurological disorders and NIBS protocols potentially able to interact with them, there are few applications of NIBS aiming to explore clinical outcomes of this interaction. Our review article aims to point out oscillatory markers of neurological, which are also suitable targets for modification by NIBS, in order to facilitate in future studies the matching of technical application to clinical targets.
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Affiliation(s)
- Assenza Giovanni
- Clinical Neurology, Campus Biomedico University of RomeRome, Italy
| | | | - Lazzaro di Biase
- Clinical Neurology, Campus Biomedico University of RomeRome, Italy
- Nuffield Department of Clinical Neurosciences, University of OxfordOxford, United Kingdom
| | - Florinda Ferreri
- Clinical Neurology, Campus Biomedico University of RomeRome, Italy
- Department of Clinical Neurophysiology, Kuopio University Hospital, University of Eastern FinlandKuopio, Finland
| | - Lucia Florio
- Clinical Neurology, Campus Biomedico University of RomeRome, Italy
| | - Andrea Guerra
- Clinical Neurology, Campus Biomedico University of RomeRome, Italy
- Nuffield Department of Clinical Neurosciences, University of OxfordOxford, United Kingdom
| | - Massimo Marano
- Clinical Neurology, Campus Biomedico University of RomeRome, Italy
| | - Matteo Paolucci
- Clinical Neurology, Campus Biomedico University of RomeRome, Italy
| | - Federico Ranieri
- Clinical Neurology, Campus Biomedico University of RomeRome, Italy
| | - Gaetano Salomone
- Clinical Neurology, Campus Biomedico University of RomeRome, Italy
| | - Mario Tombini
- Clinical Neurology, Campus Biomedico University of RomeRome, Italy
| | - Gregor Thut
- Centre for Cognitive Neuroimaging (CCNi), Institute of Neuroscience and Psychology, University of GlasgowGlasgow, United Kingdom
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30
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Karvigh SA, Motamedi M, Arzani M, Roshan JHN. HD-tDCS in refractory lateral frontal lobe epilepsy patients. Seizure 2017; 47:74-80. [DOI: 10.1016/j.seizure.2017.03.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 03/01/2017] [Accepted: 03/07/2017] [Indexed: 01/23/2023] Open
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31
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Hameed MQ, Dhamne SC, Gersner R, Kaye HL, Oberman LM, Pascual-Leone A, Rotenberg A. Transcranial Magnetic and Direct Current Stimulation in Children. Curr Neurol Neurosci Rep 2017; 17:11. [PMID: 28229395 PMCID: PMC5962296 DOI: 10.1007/s11910-017-0719-0] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Promising results in adult neurologic and psychiatric disorders are driving active research into transcranial brain stimulation techniques, particularly transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), in childhood and adolescent syndromes. TMS has realistic utility as an experimental tool tested in a range of pediatric neuropathologies such as perinatal stroke, depression, Tourette syndrome, and autism spectrum disorder (ASD). tDCS has also been tested as a treatment for a number of pediatric neurologic conditions, including ASD, attention-deficit/hyperactivity disorder, epilepsy, and cerebral palsy. Here, we complement recent reviews with an update of published TMS and tDCS results in children, and discuss developmental neuroscience considerations that should inform pediatric transcranial stimulation.
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Affiliation(s)
- Mustafa Q Hameed
- Neuromodulation Program, Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA, 02115, USA
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital Harvard Medical School, 300 Longwood Avenue, Boston, MA, 02115, USA
- Department of Neurosurgery, Boston Children's Hospital Harvard Medical School, Boston, MA, 02115, USA
| | - Sameer C Dhamne
- Neuromodulation Program, Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA, 02115, USA
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital Harvard Medical School, 300 Longwood Avenue, Boston, MA, 02115, USA
| | - Roman Gersner
- Neuromodulation Program, Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA, 02115, USA
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital Harvard Medical School, 300 Longwood Avenue, Boston, MA, 02115, USA
| | - Harper L Kaye
- Neuromodulation Program, Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA, 02115, USA
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital Harvard Medical School, 300 Longwood Avenue, Boston, MA, 02115, USA
| | - Lindsay M Oberman
- Neuroplasticity and Autism Spectrum Disorder Program and Department of Psychiatry and Human Behavior, E.P. Bradley Hospital and Warren Alpert Medical School, Brown University, Providence, RI, USA
| | - Alvaro Pascual-Leone
- Berenson-Allen Center for Noninvasive Brain Stimulation and Division for Cognitive Neurology, Beth Israel Deaconness Medical Center Harvard Medical School, Boston, MA, USA
- Institut Guttmann, Universitat Autonoma, Barcelona, Spain
| | - Alexander Rotenberg
- Neuromodulation Program, Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA, 02115, USA.
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital Harvard Medical School, 300 Longwood Avenue, Boston, MA, 02115, USA.
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San-Juan D, Espinoza López DA, Vázquez Gregorio R, Trenado C, Fernández-González Aragón M, Morales-Quezada L, Hernandez Ruiz A, Hernandez-González F, Alcaraz-Guzmán A, Anschel DJ, Fregni F. Transcranial Direct Current Stimulation in Mesial Temporal Lobe Epilepsy and Hippocampal Sclerosis. Brain Stimul 2017; 10:28-35. [DOI: 10.1016/j.brs.2016.08.013] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2016] [Revised: 08/23/2016] [Accepted: 08/29/2016] [Indexed: 11/26/2022] Open
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Zoghi M, O'Brien TJ, Kwan P, Cook MJ, Galea M, Jaberzadeh S. Cathodal transcranial direct-current stimulation for treatment of drug-resistant temporal lobe epilepsy: A pilot randomized controlled trial. Epilepsia Open 2016; 1:130-135. [PMID: 29588936 PMCID: PMC5719830 DOI: 10.1002/epi4.12020] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/16/2016] [Indexed: 01/08/2023] Open
Abstract
Objective To investigate the effect of cathodal transcranial direct‐current stimulation (c‐tDCS) on seizure frequency in patients with drug‐resistant temporal lobe epilepsy (TLE). Method Twenty‐nine patients with drug‐resistant TLE participated in this study. They were randomized to experimental or sham group. Twenty participants (experimental group) received within‐session repeated c‐tDCS intervention over the affected temporal lobe, and nine (sham group) received sham tDCS. Paired‐pulse transcranial magnetic stimulation was used to assess short interval intracortical inhibition (SICI) in primary motor cortex ipsilateral to the affected temporal lobe. SICI was measured from motor evoked potentials recorded from the contralateral first dorsal interosseous muscle. Adverse effects were monitored during and after each intervention in both groups. A seizure diary was given to each participant to complete for 4 weeks following the tDCS intervention. The mean response ratio was calculated from their seizure rates before and after the tDCS intervention. Results The experimental group showed a significant increase in SICI compared to the sham group (F = 10.3, p = 0.005). None of the participants reported side effects of moderate or severe degree. The mean response ratio in seizure frequency was −42.14% (standard deviation [SD] 35.93) for the experimental group and −16.98% (SD 52.41) for the sham group. Significance Results from this pilot study suggest that tDCS may be a safe and efficacious nonpharmacologic intervention for patients with drug‐resistant TLE. Further evaluation in larger double‐blind randomized controlled trials is warranted.
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Affiliation(s)
- Maryam Zoghi
- Department of Medicine The Royal Melbourne Hospital The University of Melbourne Parkville Victoria Australia
| | - Terence J O'Brien
- Department of Medicine The Royal Melbourne Hospital The University of Melbourne Parkville Victoria Australia
| | - Patrick Kwan
- Department of Medicine The Royal Melbourne Hospital The University of Melbourne Parkville Victoria Australia
| | - Mark J Cook
- Department of Medicine St Vincent's Hospital The University of Melbourne Fitzroy Victoria Australia
| | - Mary Galea
- Department of Medicine The Royal Melbourne Hospital (Royal Park Campus) The University of Melbourne Parkville Victoria Australia
| | - Shapour Jaberzadeh
- School of Primary Health Care Faculty of Medicine, Nursing and Health Sciences Monash University Frankston Victoria Australia
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Bikson M, Grossman P, Thomas C, Zannou AL, Jiang J, Adnan T, Mourdoukoutas AP, Kronberg G, Truong D, Boggio P, Brunoni AR, Charvet L, Fregni F, Fritsch B, Gillick B, Hamilton RH, Hampstead BM, Jankord R, Kirton A, Knotkova H, Liebetanz D, Liu A, Loo C, Nitsche MA, Reis J, Richardson JD, Rotenberg A, Turkeltaub PE, Woods AJ. Safety of Transcranial Direct Current Stimulation: Evidence Based Update 2016. Brain Stimul 2016; 9:641-661. [PMID: 27372845 PMCID: PMC5007190 DOI: 10.1016/j.brs.2016.06.004] [Citation(s) in RCA: 835] [Impact Index Per Article: 104.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 06/10/2016] [Accepted: 06/12/2016] [Indexed: 01/13/2023] Open
Abstract
This review updates and consolidates evidence on the safety of transcranial Direct Current Stimulation (tDCS). Safety is here operationally defined by, and limited to, the absence of evidence for a Serious Adverse Effect, the criteria for which are rigorously defined. This review adopts an evidence-based approach, based on an aggregation of experience from human trials, taking care not to confuse speculation on potential hazards or lack of data to refute such speculation with evidence for risk. Safety data from animal tests for tissue damage are reviewed with systematic consideration of translation to humans. Arbitrary safety considerations are avoided. Computational models are used to relate dose to brain exposure in humans and animals. We review relevant dose-response curves and dose metrics (e.g. current, duration, current density, charge, charge density) for meaningful safety standards. Special consideration is given to theoretically vulnerable populations including children and the elderly, subjects with mood disorders, epilepsy, stroke, implants, and home users. Evidence from relevant animal models indicates that brain injury by Direct Current Stimulation (DCS) occurs at predicted brain current densities (6.3-13 A/m(2)) that are over an order of magnitude above those produced by conventional tDCS. To date, the use of conventional tDCS protocols in human trials (≤40 min, ≤4 milliamperes, ≤7.2 Coulombs) has not produced any reports of a Serious Adverse Effect or irreversible injury across over 33,200 sessions and 1000 subjects with repeated sessions. This includes a wide variety of subjects, including persons from potentially vulnerable populations.
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Affiliation(s)
- Marom Bikson
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA.
| | - Pnina Grossman
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA
| | - Chris Thomas
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA
| | | | - Jimmy Jiang
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA
| | - Tatheer Adnan
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA
| | | | - Greg Kronberg
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA
| | - Dennis Truong
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA
| | - Paulo Boggio
- Cognitive Neuroscience Laboratory and Developmental Disorders Program, Center for Health and Biological Sciences, Mackenzie Presbyterian University, Sao Paulo, Brazil
| | - André R Brunoni
- Service of Interdisciplinary Neuromodulation, Department and Institute of Psychiatry, Laboratory of Neurosciences (LIM-27), University of São Paulo, São Paulo, Brazil
| | - Leigh Charvet
- NYU MS Comprehensive Care Center, Department of Neurology, New York University School of Medicine, New York, NY, USA
| | - Felipe Fregni
- Berenson-Allen Center for Noninvasive Brain Stimulation, Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Brita Fritsch
- Department of Neurology, University Medical Center, Freiburg, Germany; BrainLinks-BrainTools Cluster of Excellence, University of Freiburg, Germany
| | - Bernadette Gillick
- Department of Physical Medicine and Rehabilitation, University of Minnesota Medical School, Minneapolis, MN
| | - Roy H Hamilton
- Laboratory for Cognition and Neural Stimulation, University of Pennsylvania, Philadelphia, PA, USA; Center for Cognitive Neuroscience, University of Pennsylvania, Philadelphia, PA, USA; Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA
| | - Benjamin M Hampstead
- Mental Health Service, VA Ann Arbor Healthcare System, Ann Arbor, MI, USA; Department of Psychiatry, University of Michigan, Ann Arbor, MI, USA
| | - Ryan Jankord
- Applied Neuroscience, 711th Human Performance Wing, Air Force Research Laboratory, WPAFB, OH, USA
| | - Adam Kirton
- Departments of Pediatrics and Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Helena Knotkova
- MJHS Institute for Innovation in Palliative Care, New York, NY, USA; Department of Social and Family Medicine, Albert Einstein College of Medicine, The Bronx, NY, USA
| | - David Liebetanz
- Department of Clinical Neurophysiology, University Medical Center, Georg-August-University, Goettingen 37075, Germany
| | - Anli Liu
- NYU Comprehensive Epilepsy Center, New York University School of Medicine, New York, NY, USA
| | - Colleen Loo
- Psychiatry, Black Dog Institute, Clinical Academic, St George Hospital, University of New South Wales, Sydney, Australia
| | - Michael A Nitsche
- Department of Clinical Neurophysiology, University Medical Center, Georg-August-University, Goettingen 37075, Germany; Leibniz Research Centre for Working Environment and Human Factors at the TU Dortmund, Dortmund, Germany; Department of Neurology, University Medical Hospital Bergmannsheil, Bochum, Germany
| | - Janine Reis
- Department of Neurology, University Medical Center, Freiburg, Germany; BrainLinks-BrainTools Cluster of Excellence, University of Freiburg, Germany
| | - Jessica D Richardson
- Berenson-Allen Center for Noninvasive Brain Stimulation, Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA; Department of Communication Sciences & Disorders, The University of South Carolina, Columbia, SC, USA; Department of Speech and Hearing Sciences, The University of New Mexico, Albuquerque, NM, USA
| | - Alexander Rotenberg
- Berenson-Allen Center for Noninvasive Brain Stimulation, Division of Cognitive Neurology, Department of Neurology, Harvard Medical School and Beth Israel Deaconess Medical Center, Boston, MA, USA; Pediatric Neuromodulation Program, Division of Epilepsy and Neurophysiology, Department of Neurology, Children's Hospital Boston, Harvard Medical School, Boston, MA, USA
| | - Peter E Turkeltaub
- Department of Neurology, Georgetown University, Washington, DC, USA; Research Division, MedStar National Rehabilitation Hospital, Washington, DC, USA
| | - Adam J Woods
- Center for Cognitive Aging and Memory, Institute on Aging, Department of Aging and Geriatric Research, McKnight Brain Institute, University of Florida, Gainesville, FL, USA
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Gschwind M, Seeck M. Transcranial direct-current stimulation as treatment in epilepsy. Expert Rev Neurother 2016; 16:1427-1441. [DOI: 10.1080/14737175.2016.1209410] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Zhang C, Bin Altaf MA, Yoo J. Design and Implementation of an On-Chip Patient-Specific Closed-Loop Seizure Onset and Termination Detection System. IEEE J Biomed Health Inform 2016; 20:996-1007. [DOI: 10.1109/jbhi.2016.2553368] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Assenza G, Campana C, Formica D, Schena E, Taffoni F, Di Pino G, Di Lazzaro V. Efficacy of cathodal transcranial direct current stimulation in drug-resistant epilepsy: a proof of principle. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2016; 2014:530-3. [PMID: 25570013 DOI: 10.1109/embc.2014.6943645] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
It has been proved that Transcranial DCS (tDCS) can modulate cortical excitability, enhancing or decreasing, respectively by anodal or cathodal polarity. The short-term and lasting alterations induced by tDCS are strictly related to the charge density, duration of stimulation and the depth of neuron below the skull. Epilepsy represents a pathophysiological model of unbalanced relation between cortical excitation and inhibition. In this line, tDCS can be exploited to counterbalance the neuronal hyper-excitation through electric neural modulation. This paper aims at providing the efficacy of cathodal tDCS in reducing seizures' frequency in drug-resistant focal epilepsy. The study was single blind and sham-controlled with an observation period of one month during which the patients or the caregivers provided a detailed seizures' calendar (frequency as n°/week; basal, post sham and post tDCS). Patients received sham or real tDCS treatment on the 8th and 22th days. Two patients affected by focal resistant epilepsy were enrolled. They both underwent a consistent reduction of the seizures'frequency: about 70 % for Patient 1 and about 50% for Patient 2. This study represents the proof that cathodal tDCS may be efficient in reducing seizures'frequency in focal resistant epilepsy.
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Boonstra TW, Nikolin S, Meisener AC, Martin DM, Loo CK. Change in Mean Frequency of Resting-State Electroencephalography after Transcranial Direct Current Stimulation. Front Hum Neurosci 2016; 10:270. [PMID: 27375462 PMCID: PMC4893480 DOI: 10.3389/fnhum.2016.00270] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 05/20/2016] [Indexed: 11/25/2022] Open
Abstract
Transcranial direct current stimulation (tDCS) is proposed as a tool to investigate cognitive functioning in healthy people and as a treatment for various neuropathological disorders. However, the underlying cortical mechanisms remain poorly understood. We aim to investigate whether resting-state electroencephalography (EEG) can be used to monitor the effects of tDCS on cortical activity. To this end we tested whether the spectral content of ongoing EEG activity is significantly different after a single session of active tDCS compared to sham stimulation. Twenty participants were tested in a sham-controlled, randomized, crossover design. Resting-state EEG was acquired before, during and after active tDCS to the left dorsolateral prefrontal cortex (15 min of 2 mA tDCS) and sham stimulation. Electrodes with a diameter of 3.14 cm2 were used for EEG and tDCS. Partial least squares (PLS) analysis was used to examine differences in power spectral density (PSD) and the EEG mean frequency to quantify the slowing of EEG activity after stimulation. PLS revealed a significant increase in spectral power at frequencies below 15 Hz and a decrease at frequencies above 15 Hz after active tDCS (P = 0.001). The EEG mean frequency was significantly reduced after both active tDCS (P < 0.0005) and sham tDCS (P = 0.001), though the decrease in mean frequency was smaller after sham tDCS than after active tDCS (P = 0.073). Anodal tDCS of the left DLPFC using a high current density bi-frontal electrode montage resulted in general slowing of resting-state EEG. The similar findings observed following sham stimulation question whether the standard sham protocol is an appropriate control condition for tDCS.
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Affiliation(s)
- Tjeerd W Boonstra
- School of Psychiatry, University of New South WalesSydney, NSW, Australia; Black Dog Institute, University of New South WalesSydney, NSW, Australia
| | - Stevan Nikolin
- School of Psychiatry, University of New South WalesSydney, NSW, Australia; Black Dog Institute, University of New South WalesSydney, NSW, Australia
| | - Ann-Christin Meisener
- School of Psychiatry, University of New South WalesSydney, NSW, Australia; Institute of Cognitive Science, University of OsnabruckLower Saxony, Germany
| | - Donel M Martin
- School of Psychiatry, University of New South WalesSydney, NSW, Australia; Black Dog Institute, University of New South WalesSydney, NSW, Australia
| | - Colleen K Loo
- School of Psychiatry, University of New South WalesSydney, NSW, Australia; Black Dog Institute, University of New South WalesSydney, NSW, Australia; Department of Psychiatry, St. George Hospital, South Eastern Sydney HealthSydney, NSW, Australia
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Palm U, Segmiller FM, Epple AN, Freisleder FJ, Koutsouleris N, Schulte-Körne G, Padberg F. Transcranial direct current stimulation in children and adolescents: a comprehensive review. J Neural Transm (Vienna) 2016; 123:1219-34. [PMID: 27173384 DOI: 10.1007/s00702-016-1572-z] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 05/06/2016] [Indexed: 12/23/2022]
Abstract
Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation method that has shown promising results in various neuropsychiatric disorders in adults. This review addresses the therapeutic use of tDCS in children and adolescents including safety, ethical, and legal considerations. There are several studies addressing the dosage of tDCS in children and adolescents by computational modeling of electric fields in the pediatric brain. Results suggest halving the amperage used in adults to obtain the same peak electric fields, however, there are some studies reporting on the safe application of tDCS with standard adult parameters in children (2 mA; 20-30 min). There are several randomized placebo controlled trials suggesting beneficial effects of tDCS for the treatment of cerebral palsy. For dystonia there are mixed data. Some studies suggest efficacy of tDCS for the treatment of refractory epilepsy, and for the improvement of attention deficit/hyperactivity disorder and autism. Interestingly, there is a lack of data for the treatment of childhood and adolescent psychiatric disorders, i.e., childhood onset schizophrenia and affective disorders. Overall, tDCS seems to be safe in pediatric population. More studies are needed to confirm the preliminary encouraging results; however, ethical deliberation has to be weighed carefully for every single case.
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Affiliation(s)
- Ulrich Palm
- Department of Psychiatry and Psychotherapy, Klinikum der Universität München, Nußbaumstr. 7, 80336, Munich, Germany.
| | - Felix M Segmiller
- Department of Psychiatry and Psychotherapy, Klinikum der Universität München, Nußbaumstr. 7, 80336, Munich, Germany
| | | | | | - Nikolaos Koutsouleris
- Department of Psychiatry and Psychotherapy, Klinikum der Universität München, Nußbaumstr. 7, 80336, Munich, Germany
| | - Gerd Schulte-Körne
- Department of Childhood and Adolescent Psychiatry, Klinikum der Universität München, Munich, Germany
| | - Frank Padberg
- Department of Psychiatry and Psychotherapy, Klinikum der Universität München, Nußbaumstr. 7, 80336, Munich, Germany
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Baeken C, Brunelin J, Duprat R, Vanderhasselt MA. The application of tDCS in psychiatric disorders: a brain imaging view. SOCIOAFFECTIVE NEUROSCIENCE & PSYCHOLOGY 2016; 6:29588. [PMID: 26993785 PMCID: PMC4799388 DOI: 10.3402/snp.v6.29588] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 11/20/2015] [Accepted: 01/11/2016] [Indexed: 12/24/2022]
Abstract
Background Transcranial direct current stimulation (tDCS) is a non-invasive, non-convulsive technique for modulating brain function. In contrast to other non-invasive brain stimulation techniques, where costs, clinical applicability, and availability limit their large-scale use in clinical practices, the low-cost, portable, and easy-to-use tDCS devices may overcome these restrictions. Objective Despite numerous clinical applications in large numbers of patients suffering from psychiatric disorders, it is not quite clear how tDCS influences the mentally affected human brain. In order to decipher potential neural mechanisms of action of tDCS in patients with psychiatric conditions, we focused on the combination of tDCS with neuroimaging techniques. Design We propose a contemporary overview on the currently available neurophysiological and neuroimaging data where tDCS has been used as a research or treatment tool in patients with psychiatric disorders. Results Over a reasonably short period of time, tDCS has been broadly used as a research tool to examine neuronal processes in the healthy brain. tDCS has also commonly been applied as a treatment application in a variety of mental disorders, with to date no straightforward clinical outcome and not always accompanied by brain imaging techniques. Conclusion tDCS, as do other neuromodulation devices, clearly affects the underlying neuronal processes. However, research on these mechanisms in psychiatric patients is rather limited. A better comprehension of how tDCS modulates brain function will help us to define optimal parameters of stimulation in each indication and may result in the detection of biomarkers in favor of clinical response.
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Affiliation(s)
- Chris Baeken
- Department of Psychiatry and Medical Psychology, Ghent University Hospital, Ghent University, Ghent, Belgium.,Department of Psychiatry University Hospital (UZBrussel), Brussels, Belgium.,Ghent Experimental Psychiatry (GHEP) Lab, Ghent, Belgium;
| | - Jerome Brunelin
- INSERM U1028, CNRS UMR5292, PSYR2 Team, Lyon Neuroscience Research Center, Centre Hospitalier Le Vinatier, Université Claude Bernard Lyon 1, Villeurbanne, France.,CIRRIS-Centre Interdisciplinaire de Recherche en Réadaptation et en Intégration Sociale, Université Laval, Québec, Canada
| | - Romain Duprat
- Department of Psychiatry and Medical Psychology, Ghent University Hospital, Ghent University, Ghent, Belgium.,Ghent Experimental Psychiatry (GHEP) Lab, Ghent, Belgium
| | - Marie-Anne Vanderhasselt
- Department of Psychiatry and Medical Psychology, Ghent University Hospital, Ghent University, Ghent, Belgium.,Faculty of Medicine and Pharmacy, Free University Brussels, Brussels, Belgium
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Liu A, Bryant A, Jefferson A, Friedman D, Minhas P, Barnard S, Barr W, Thesen T, O'Connor M, Shafi M, Herman S, Devinsky O, Pascual-Leone A, Schachter S. Exploring the efficacy of a 5-day course of transcranial direct current stimulation (TDCS) on depression and memory function in patients with well-controlled temporal lobe epilepsy. Epilepsy Behav 2016; 55:11-20. [PMID: 26720704 DOI: 10.1016/j.yebeh.2015.10.032] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 10/17/2015] [Accepted: 10/18/2015] [Indexed: 11/18/2022]
Abstract
INTRODUCTION Depression and memory dysfunction significantly impact the quality of life of patients with epilepsy. Current therapies for these cognitive and psychiatric comorbidities are limited. We explored the efficacy and safety of transcranial direct current stimulation (TDCS) for treating depression and memory dysfunction in patients with temporal lobe epilepsy (TLE). METHODS Thirty-seven (37) adults with well-controlled TLE were enrolled in a double-blinded, sham-controlled, randomized, parallel-group study of 5 days of fixed-dose (2 mA, 20 min) TDCS. Subjects were randomized to receive either real or sham TDCS, both delivered over the left dorsolateral prefrontal cortex. Patients received neuropsychological testing and a 20-minute scalp EEG at baseline immediately after the TDCS course and at 2- and 4-week follow-up. RESULTS There was improvement in depression scores immediately after real TDCS, but not sham TDCS, as measured by changes in the Beck Depression Inventory (BDI change: -1.68 vs. 1.27, p<0.05) and NDDI-E (-0.83 vs. 0.9091, p=0.05). There was no difference between the groups at the 2- or 4-week follow-up. There was no effect on delayed or working memory performance. Transcranial direct current stimulation was well-tolerated and did not increase seizure frequency or interictal discharge frequency. Transcranial direct current stimulation induced an increase in delta frequency band power over the frontal region and delta, alpha, and theta band power in the occipital region after real stimulation compared to sham stimulation, although the difference did not reach statistical significance. DISCUSSION This study provides evidence for the use of TDCS as a safe and well-tolerated nonpharmacologic approach to improving depressive symptoms in patients with well-controlled TLE. However, there were no changes in memory function immediately following or persisting after a stimulation course. Further studies may determine optimal stimulation parameters for maximal mood benefit.
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Affiliation(s)
- Anli Liu
- NYU Comprehensive Epilepsy Center, USA; NYU School of Medicine, USA; Berenson Allen Center for Non-invasive Brain Stimulation, Division of Cognitive Neurology, USA.
| | - Andrew Bryant
- NYU Comprehensive Epilepsy Center, USA; NYU Graduate School of Psychology, USA
| | - Ashlie Jefferson
- NYU Comprehensive Epilepsy Center, USA; NYU Graduate School of Psychology, USA
| | - Daniel Friedman
- NYU Comprehensive Epilepsy Center, USA; NYU School of Medicine, USA
| | - Preet Minhas
- NYU Comprehensive Epilepsy Center, USA; NYU School of Medicine, USA
| | - Sarah Barnard
- NYU Comprehensive Epilepsy Center, USA; NYU School of Medicine, USA
| | - William Barr
- NYU Comprehensive Epilepsy Center, USA; NYU School of Medicine, USA
| | - Thomas Thesen
- NYU Comprehensive Epilepsy Center, USA; NYU School of Medicine, USA
| | - Margaret O'Connor
- Beth Israel Deaconess Medical Center, USA; Harvard Medical School, USA
| | - Mouhsin Shafi
- Beth Israel Deaconess Medical Center, USA; Berenson Allen Center for Non-invasive Brain Stimulation, Division of Cognitive Neurology, USA; Harvard Medical School, USA
| | - Susan Herman
- Beth Israel Deaconess Medical Center, USA; Harvard Medical School, USA
| | - Orrin Devinsky
- NYU Comprehensive Epilepsy Center, USA; NYU School of Medicine, USA
| | - Alvaro Pascual-Leone
- Beth Israel Deaconess Medical Center, USA; Berenson Allen Center for Non-invasive Brain Stimulation, Division of Cognitive Neurology, USA; Harvard Medical School, USA
| | - Steven Schachter
- Beth Israel Deaconess Medical Center, USA; Harvard Medical School, USA
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Abstract
Transcranial direct current stimulation (tDCS) is a technique for noninvasively stimulating specific cortical regions of the brain with small (<2 mA) and constant direct current on the scalp. tDCS has been widely applied, not only for medical treatment, but also for cognitive and somatosensory function enhancement, motor learning improvement, and social behavioral change. However, the mechanism that underlies the effect of tDCS is unclear. In this study, we performed simultaneous electroencephalogram (EEG) monitoring during tDCS to understand the dynamic electrophysiological changes throughout the stimulation. A total of 10 healthy individuals participated in this experiment. We recorded EEGs with direct current stimulation, as well as during a 5-min resting state before and after the stimulation. All participants kept their eyes closed during the experiment. Anode and cathode patches of tDCS were placed on the left and the right dorsolateral prefrontal cortex, respectively. In addition, an EEG electrode was placed on the medial prefrontal cortex. The beta-frequency power increased promptly after starting the stimulation. The significant beta-power increase was maintained during the stimulation. Other frequency bands did not show any significant changes. The results indicate that tDCS of the left dorsolateral prefrontal cortex changed the brain to a ready state for efficient cognitive functioning by increasing the beta-frequency power. This is the first attempt to simultaneously stimulate the cortex and record the EEG and then systematically analyze the prestimulation, during-stimulation, and poststimulation EEG data.
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Slow-oscillatory Transcranial Direct Current Stimulation Modulates Memory in Temporal Lobe Epilepsy by Altering Sleep Spindle Generators: A Possible Rehabilitation Tool. Brain Stimul 2015; 8:567-73. [DOI: 10.1016/j.brs.2015.01.410] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 01/07/2015] [Accepted: 01/12/2015] [Indexed: 11/23/2022] Open
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Roy A, Baxter B, He B. High-definition transcranial direct current stimulation induces both acute and persistent changes in broadband cortical synchronization: a simultaneous tDCS-EEG study. IEEE Trans Biomed Eng 2015; 61:1967-78. [PMID: 24956615 DOI: 10.1109/tbme.2014.2311071] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The goal of this study was to develop methods for simultaneously acquiring electrophysiological data during high-definition transcranial direct current stimulation (tDCS) using high-resolution electroencephalography (EEG). Previous studies have pointed to the after-effects of tDCS on both motor and cognitive performance, and there appears to be potential for using tDCS in a variety of clinical applications. However, little is known about the real-time effects of tDCS on rhythmic cortical activity in humans due to the technical challenges of simultaneously obtaining electrophysiological data during ongoing stimulation. Furthermore, the mechanisms of action of tDCS in humans are not well understood. We have conducted a simultaneous tDCS-EEG study in a group of healthy human subjects. Significant acute and persistent changes in spontaneous neural activity and event-related synchronization (ERS) were observed during and after the application of high-definition tDCS over the left sensorimotor cortex. Both anodal and cathodal stimulation resulted in acute global changes in broadband cortical activity which were significantly different than the changes observed in response to sham stimulation. For the group of eight subjects studied, broadband individual changes in spontaneous activity during stimulation were apparent both locally and globally. In addition, we found that high-definition tDCS of the left sensorimotor cortex can induce significant ipsilateral and contralateral changes in event-related desynchronization and ERS during motor imagination following the end of the stimulation period. Overall, our results demonstrate the feasibility of acquiring high-resolution EEG during high-definition tDCS and provide evidence that tDCS in humans directly modulates rhythmic cortical synchronization during and after its administration.
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McKendrick R, Parasuraman R, Ayaz H. Wearable functional near infrared spectroscopy (fNIRS) and transcranial direct current stimulation (tDCS): expanding vistas for neurocognitive augmentation. Front Syst Neurosci 2015; 9:27. [PMID: 25805976 PMCID: PMC4353303 DOI: 10.3389/fnsys.2015.00027] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2014] [Accepted: 02/14/2015] [Indexed: 12/02/2022] Open
Abstract
Contemporary studies with transcranial direct current stimulation (tDCS) provide a growing base of evidence for enhancing cognition through the non-invasive delivery of weak electric currents to the brain. The main effect of tDCS is to modulate cortical excitability depending on the polarity of the applied current. However, the underlying mechanism of neuromodulation is not well understood. A new generation of functional near infrared spectroscopy (fNIRS) systems is described that are miniaturized, portable, and include wearable sensors. These developments provide an opportunity to couple fNIRS with tDCS, consistent with a neuroergonomics approach for joint neuroimaging and neurostimulation investigations of cognition in complex tasks and in naturalistic conditions. The effects of tDCS on complex task performance and the use of fNIRS for monitoring cognitive workload during task performance are described. Also explained is how fNIRS + tDCS can be used simultaneously for assessing spatial working memory. Mobile optical brain imaging is a promising neuroimaging tool that has the potential to complement tDCS for realistic applications in natural settings.
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Affiliation(s)
- Ryan McKendrick
- Center of Excellence in Neuroergonomics, Technology, and Cognition (CENTEC), George Mason University Fairfax, VA, USA
| | - Raja Parasuraman
- Center of Excellence in Neuroergonomics, Technology, and Cognition (CENTEC), George Mason University Fairfax, VA, USA
| | - Hasan Ayaz
- School of Biomedical Engineering, Science and Health Systems, Drexel University Philadelphia, PA, USA
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Ulam F, Shelton C, Richards L, Davis L, Hunter B, Fregni F, Higgins K. Cumulative effects of transcranial direct current stimulation on EEG oscillations and attention/working memory during subacute neurorehabilitation of traumatic brain injury. Clin Neurophysiol 2015; 126:486-96. [DOI: 10.1016/j.clinph.2014.05.015] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Revised: 04/25/2014] [Accepted: 05/22/2014] [Indexed: 11/30/2022]
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San-Juan D, Morales-Quezada L, Orozco Garduño AJ, Alonso-Vanegas M, González-Aragón MF, Espinoza López DA, Vázquez Gregorio R, Anschel DJ, Fregni F. Transcranial Direct Current Stimulation in Epilepsy. Brain Stimul 2015; 8:455-64. [PMID: 25697590 DOI: 10.1016/j.brs.2015.01.001] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Revised: 01/02/2015] [Accepted: 01/05/2015] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Transcranial direct current stimulation (tDCS) is an emerging non-invasive neuromodulation therapy in epilepsy with conflicting results in terms of efficacy and safety. OBJECTIVE Review the literature about the efficacy and safety of tDCS in epilepsy in humans and animals. METHODS We searched studies in PubMed, MedLine, Scopus, Web of Science and Google Scholar (January 1969 to October 2013) using the keywords 'transcranial direct current stimulation' or 'tDCS' or 'brain polarization' or 'galvanic stimulation' and 'epilepsy' in animals and humans. Original articles that reported tDCS safety and efficacy in epileptic animals or humans were included. Four review authors independently selected the studies, extracted data and assessed the methodological quality of the studies using the recommendations of the Cochrane Handbook for Systematic Reviews of Interventions, PRISMA guidelines and Jadad Scale. A meta-analysis was not possible due to methodological, clinical and statistical heterogeneity of included studies. RESULTS We analyzed 9 articles with different methodologies (3 animals/6 humans) with a total of 174 stimulated individuals; 109 animals and 65 humans. In vivo and in vitro animal studies showed that direct current stimulation can successfully induce suppression of epileptiform activity without neurological injury and 4/6 (67%) clinical studies showed an effective decrease in epileptic seizures and 5/6 (83%) reduction of inter-ictal epileptiform activity. All patients tolerated tDCS well. CONCLUSIONS tDCS trials have demonstrated preliminary safety and efficacy in animals and patients with epilepsy. Further larger studies are needed to define the best stimulation protocols and long-term follow-up.
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Affiliation(s)
- Daniel San-Juan
- Neurophysiology Department, National Institute of Neurology and Neurosurgery "Manuel Velasco Suárez", Av. Insurgentes Sur 3877, Col. La Fama, Tlalpan, México D.F. 14269, Mexico.
| | - León Morales-Quezada
- Laboratory of Neuromodulation, Department of Physical Medicine & Rehabilitation, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard Medical School, 300 1st Ave, Charlestown, MA 02129, USA
| | - Adolfo Josué Orozco Garduño
- Neurophysiology Department, National Institute of Neurology and Neurosurgery "Manuel Velasco Suárez", Av. Insurgentes Sur 3877, Col. La Fama, Tlalpan, México D.F. 14269, Mexico
| | - Mario Alonso-Vanegas
- Neurosurgery Department, National Institute of Neurology and Neurosurgery "Manuel Velasco Suárez", Av. Insurgentes Sur 3877, Col. La Fama, Tlalpan, México D.F. 14269, Mexico
| | - Maricarmen Fernández González-Aragón
- Neurophysiology Department, National Institute of Neurology and Neurosurgery "Manuel Velasco Suárez", Av. Insurgentes Sur 3877, Col. La Fama, Tlalpan, México D.F. 14269, Mexico
| | - Dulce Anabel Espinoza López
- Neurophysiology Department, National Institute of Neurology and Neurosurgery "Manuel Velasco Suárez", Av. Insurgentes Sur 3877, Col. La Fama, Tlalpan, México D.F. 14269, Mexico
| | - Rafael Vázquez Gregorio
- Neurophysiology Department, National Institute of Neurology and Neurosurgery "Manuel Velasco Suárez", Av. Insurgentes Sur 3877, Col. La Fama, Tlalpan, México D.F. 14269, Mexico
| | - David J Anschel
- Comprehensive Epilepsy Center of Long Island, St. Charles Hospital, 200 Belle Terre Rd., Port Jefferson, NY 11777, USA
| | - Felipe Fregni
- Laboratory of Neuromodulation, Department of Physical Medicine & Rehabilitation, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard Medical School, 300 1st Ave, Charlestown, MA 02129, USA
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Intensity dependent effects of transcranial direct current stimulation on corticospinal excitability in chronic spinal cord injury. Arch Phys Med Rehabil 2014; 96:S114-21. [PMID: 25461825 DOI: 10.1016/j.apmr.2014.11.004] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 10/07/2014] [Accepted: 11/03/2014] [Indexed: 01/24/2023]
Abstract
OBJECTIVE To investigate the effects of anodal transcranial direct current stimulation (a-tDCS) intensity on corticospinal excitability and affected muscle activation in individuals with chronic spinal cord injury (SCI). DESIGN Single-blind, randomized, sham-controlled, crossover study. SETTING Medical research institute and rehabilitation hospital. PARTICIPANTS Volunteers (N = 9) with chronic SCI and motor dysfunction in wrist extensor muscles. INTERVENTIONS Three single session exposures to 20 minutes of a-tDCS (anode over the extensor carpi radialis [ECR] muscle representation on the left primary motor cortex, cathode over the right supraorbital area) using 1 mA, 2 mA, or sham stimulation, delivered at rest, with at least 1 week between sessions. MAIN OUTCOME MEASURES Corticospinal excitability was assessed with motor-evoked potentials (MEPs) from the ECR muscle using surface electromyography after transcranial magnetic stimulation. Changes in spinal excitability, sensory threshold, and muscle strength were also investigated. RESULTS Mean MEP amplitude significantly increased by approximately 40% immediately after 2mA a-tDCS (pre: 0.36 ± 0.1 mV; post: 0.47 ± 0.11 mV; P = .001), but not with 1 mA or sham. Maximal voluntary contraction measures remained unaltered across all conditions. Sensory threshold significantly decreased over time after 1mA (P = .002) and 2mA (P = .039) a-tDCS and did not change with sham. F-wave persistence showed a nonsignificant trend for increase (pre: 32% ± 12%; post: 41% ± 10%; follow-up: 46% ± 12%) after 2 mA stimulation. No adverse effects were reported with any of the experimental conditions. CONCLUSIONS The a-tDCS can transiently raise corticospinal excitability to affected muscles in patients with chronic SCI after 2 mA stimulation. Sensory perception can improve with both 1 and 2 mA stimulation. This study gives support to the safe and effective use of a-tDCS using small electrodes in patients with SCI and highlights the importance of stimulation intensity.
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