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Shoaib Z, Chang WK, Lee J, Lee SH, Phillips V Z, Lee SH, Paik NJ, Hwang HJ, Kim WS. Investigation of Neuromodulatory Effect of Anodal Cerebellar Transcranial Direct Current Stimulation on the Primary Motor Cortex Using Functional Near-Infrared Spectroscopy. CEREBELLUM (LONDON, ENGLAND) 2024; 23:56-66. [PMID: 36633829 DOI: 10.1007/s12311-023-01511-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 01/03/2023] [Indexed: 01/13/2023]
Abstract
Cerebellar brain inhibition (CBI), a neural connection between the cerebellum and primary motor cortex (M1), has been researched as a target pathway for neuromodulation to improve clinical outcomes in various neurological diseases. However, conflicting results of anodal cerebellar transcranial direct current stimulation (acb-tDCS) on M1 excitability indicate that additional investigation is required to examine its precise effect. This study aimed to gather evidence of the neuromodulatory effect of acb-tDCS on the M1 using functional near-infrared spectroscopy (fNIRS). Sixteen healthy participants were included in this cross-over study. Participants received real and sham acb-tDCS randomly, with a minimum 1-week washout period between them. The anode and cathode were placed on the right cerebellum and the right buccinator muscle, respectively. Stimulation lasted 20 min at an intensity of 2 mA, and fNIRS data were recorded for 42 min (including a 4-min baseline before stimulation and an 18-min post-stimulation duration) using eight channels attached bilaterally on the M1. acb-tDCS induced a significant decrease in oxyhemoglobin (HbO) concentration (inhibitory effect) in the left (contralateral) M1, whereas it induced a significant increase in HbO concentration (excitatory effect) in the right (ipsilateral) M1 compared to sham tDCS during (p < 0.05) and after stimulation (p < 0.01) in a group level analysis. At the individual level, variations in response to acb-tDCS were observed. Our findings demonstrate the neuromodulatory effects of acb-tDCS on the bilateral M1 in terms of neuronal hemodynamics.
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Affiliation(s)
- Zeshan Shoaib
- Department of Electronics and Information Engineering, Korea University, Sejong City, South Korea
- Department of Rehabilitation Medicine, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Won Kee Chang
- Department of Rehabilitation Medicine, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Jongseung Lee
- Department of Rehabilitation Medicine, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Stephanie Hyeyoung Lee
- Department of Rehabilitation Medicine, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Zephaniah Phillips V
- Global Health Technology Research Center, College of Health Science, Korea University, Seoul, South Korea
| | - Seung Hyun Lee
- Interdisciplinary Program in Precision Public Health, Korea University, Seoul, South Korea
| | - Nam-Jong Paik
- Department of Rehabilitation Medicine, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Han-Jeong Hwang
- Department of Electronics and Information Engineering, Korea University, Sejong City, South Korea.
- Interdisciplinary Graduate Program for Artificial Intelligence Smart Convergence Technology, Korea University, Sejong City, South Korea.
| | - Won-Seok Kim
- Department of Rehabilitation Medicine, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea.
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Kho SK, Keeble D, Wong HK, Estudillo AJ. Null effect of anodal and cathodal transcranial direct current stimulation (tDCS) on own- and other-race face recognition. Soc Neurosci 2023; 18:393-406. [PMID: 37840302 DOI: 10.1080/17470919.2023.2263924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Indexed: 10/17/2023]
Abstract
Successful face recognition is important for social interactions and public security. Although some preliminary evidence suggests that anodal and cathodal transcranial direct current stimulation (tDCS) might modulate own- and other-race face identification, respectively, the findings are largely inconsistent. Hence, we examined the effect of both anodal and cathodal tDCS on the recognition of own- and other-race faces. Ninety participants first completed own- and other-race Cambridge Face Memory Test (CFMT) as baseline measurements. Next, they received either anodal tDCS, cathodal tDCS or sham stimulation and finally they completed alternative versions of the own- and other-race CFMT. No difference in performance, in terms of accuracy and reaction time, for own- and other-race face recognition between anodal tDCS, cathodal tDCS and sham stimulation was found. Our findings cast doubt upon the efficacy of tDCS to modulate performance in face identification tasks.
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Affiliation(s)
- Siew Kei Kho
- Department of Psychology, Bournemouth University, Poole, United Kingdom
- School of Psychology, University of Nottingham Malaysia, Semenyih, Malaysia
| | - David Keeble
- Department of Psychology, Bournemouth University, Poole, United Kingdom
| | - Hoo Keat Wong
- Department of Psychology, Bournemouth University, Poole, United Kingdom
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Filmer HL, Loughnan K, Seeto JX, Ballard T, Ehrhardt SE, Shaw TB, Wards Y, Rideaux R, Leow LA, Sewell DK, Dux PE. Individual Differences in Decision Strategy Relate to Neurochemical Excitability and Cortical Thickness. J Neurosci 2023; 43:7006-7015. [PMID: 37657932 PMCID: PMC10586534 DOI: 10.1523/jneurosci.1086-23.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2023] [Revised: 08/22/2023] [Accepted: 08/26/2023] [Indexed: 09/03/2023] Open
Abstract
The speed-accuracy trade-off (SAT), whereby faster decisions increase the likelihood of an error, reflects a cognitive strategy humans must engage in during the performance of almost all daily tasks. To date, computational modeling has implicated the latent decision variable of response caution (thresholds), the amount of evidence required for a decision to be made, in the SAT. Previous imaging has associated frontal regions, notably the left prefrontal cortex and the presupplementary motor area (pre-SMA), with the setting of such caution levels. In addition, causal brain stimulation studies, using transcranial direct current stimulation (tDCS), have indicated that while both of these regions are involved in the SAT, their role appears to be dissociable. tDCS efficacy to impact decision-making processes has previously been linked with neurochemical concentrations and cortical thickness of stimulated regions. However, to date, it is unknown whether these neurophysiological measures predict individual differences in the SAT, and brain stimulation effects on the SAT. Using ultra-high field (7T) imaging, here we report that instruction-based adjustments in caution are associated with both neurochemical excitability (the balance between GABA+ and glutamate) and cortical thickness across a range of frontal regions in both sexes. In addition, cortical thickness, but not neurochemical concentrations, was associated with the efficacy of left prefrontal and superior medial frontal cortex (SMFC) stimulation to modulate performance. Overall, our findings elucidate key neurophysiological predictors, frontal neural excitation, of individual differences in latent psychological processes and the efficacy of stimulation to modulate these.SIGNIFICANCE STATEMENT The speed-accuracy trade-off (SAT), faster decisions increase the likelihood of an error, reflects a cognitive strategy humans must engage in during most daily tasks. The SAT is often investigated by explicitly instructing participants to prioritize speed or accuracy when responding to stimuli. Using ultra-high field (7T) magnetic resonance imaging (MRI), we found that individual differences in the extent to which participants adjust their decision strategies with instruction related to neurochemical excitability (ratio of GABA+ to glutamate) and cortical thickness in the frontal cortex. Moreover, brain stimulation to the left prefrontal cortex and the superior medial frontal cortex (SMFC) modulated performance, with the efficacy specifically related to cortical thickness. This work sheds new light on the neurophysiological basis of decision strategies and brain stimulation.
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Affiliation(s)
- Hannah L Filmer
- School of Psychology, The University of Queensland, St Lucia, Queensland 4072, Australia
| | - Kathleen Loughnan
- School of Psychology, The University of Queensland, St Lucia, Queensland 4072, Australia
| | - Jennifer X Seeto
- School of Psychology, The University of Queensland, St Lucia, Queensland 4072, Australia
| | - Timothy Ballard
- School of Psychology, The University of Queensland, St Lucia, Queensland 4072, Australia
| | - Shane E Ehrhardt
- School of Psychology, The University of Queensland, St Lucia, Queensland 4072, Australia
| | - Thomas B Shaw
- School of Information Technology and Electrical Engineering, The University of Queensland, St Lucia, Queensland 4072, Australia
- Centre for Advanced Imaging, The University of Queensland, St Lucia, Queensland 4072, Australia
| | - Yohan Wards
- School of Psychology, The University of Queensland, St Lucia, Queensland 4072, Australia
| | - Reuben Rideaux
- Queensland Brain Institute, The University of Queensland, St Lucia, Queensland 4072, Australia
- School of Psychology, The University of Sydney, Camperdown, New South Wales 2050, Australia
| | - Li-Ann Leow
- School of Psychology, The University of Queensland, St Lucia, Queensland 4072, Australia
| | - David K Sewell
- School of Psychology, The University of Queensland, St Lucia, Queensland 4072, Australia
| | - Paul E Dux
- School of Psychology, The University of Queensland, St Lucia, Queensland 4072, Australia
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Johari K, Tabari F, Desai RH. Right frontal HD-tDCS reveals causal involvement of time perception networks in temporal processing of concepts. Sci Rep 2023; 13:16658. [PMID: 37789056 PMCID: PMC10547783 DOI: 10.1038/s41598-023-43416-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Accepted: 09/23/2023] [Indexed: 10/05/2023] Open
Abstract
Evidence suggests that perceptual and action related features of concepts are grounded in the corresponding sensory-motor networks in the human brain. However, less is known about temporal features of event concepts (e.g., a lecture) and whether they are grounded in time perception networks. We examined this question by stimulating the right dorsolateral prefrontal cortex (rDLPFC)-a part of time perception network-using HD-tDCS and subsequently recording EEG while participants performed semantic and time perception tasks. Semantic tasks were composed of event noun duration judgment (EDur), object noun size judgement (OSize), event (EVal) and object noun valence judgement. In the time perception task, participants judged the durations of pure tones. Results showed that cathodal stimulation accelerated responses for time perception task and decreased the magnitude of global field power (GFP) compared to sham stimulation. Semantic tasks results revealed that cathodal, but not sham, stimulation significantly decreased GFP for EDur relative to OSize, and to EVal. These findings provide first causal evidence that temporal features of event words are grounded in the rDLPFC as part of the temporal cognition network and shed light on the conceptual processing of time.
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Affiliation(s)
- Karim Johari
- Human Neurophysiology and Neuromodulation Laboratory, Department of Communication Science and Disorders, Louisiana State University, 86 Hatcher Hall, Field House Drive, Baton Rouge, LA, 70803, USA.
| | - Fatemeh Tabari
- Human Neurophysiology and Neuromodulation Laboratory, Department of Communication Science and Disorders, Louisiana State University, 86 Hatcher Hall, Field House Drive, Baton Rouge, LA, 70803, USA
| | - Rutvik H Desai
- Department of Psychology, University of South Carolina, Columbia, SC, USA
- Institute for Mind and Brain, University of South Carolina, Columbia, SC, USA
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Klees-Themens G, Théoret H. The effects of transcranial direct current stimulation on corticospinal excitability: A systematic review of nonsignificant findings. Eur J Neurosci 2023; 58:3074-3097. [PMID: 37407275 DOI: 10.1111/ejn.16073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 06/05/2023] [Accepted: 06/12/2023] [Indexed: 07/07/2023]
Abstract
Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that can modulate brain activity through the application of low-intensity electrical currents. Based on its reported effects on corticospinal excitability (CSE), tDCS has been used to study cognition in healthy individuals and reduce symptoms in a variety of clinical conditions. Despite its increasing popularity as a research and clinical tool, high interindividual variability has been reported in the response to protocols using transcranial magnetic stimulation (TMS) to assess tDCS-induced changes in CSE leading to several nonsignificant findings. In this systematic review, studies that reported no significant modulation of CSE following tDCS were identified from PubMed and Embase (Ovid) databases. Forty-three articles were identified where demographic, TMS and tDCS parameters were extracted. Overall, stimulation parameters, CSE measurements and participant characteristics were similar to those described in studies reporting positive results and were likewise heterogeneous between studies. Small sample sizes and inadequate blinding were notable features of the reviewed studies. This systematic review suggests that studies reporting nonsignificant findings do not markedly differ from those reporting significant modulation of CSE.
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Affiliation(s)
| | - Hugo Théoret
- Department of Psychology, Université de Montréal, Montreal, Québec, Canada
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Watanabe A, Sawamura D, Nakazono H, Tokikuni Y, Miura H, Sugawara K, Fuyama K, Tohyama H, Yoshida S, Sakai S. Transcranial direct current stimulation to the left dorsolateral prefrontal cortex enhances early dexterity skills with the left non-dominant hand: a randomized controlled trial. J Transl Med 2023; 21:143. [PMID: 36823635 PMCID: PMC9951449 DOI: 10.1186/s12967-023-03989-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 02/14/2023] [Indexed: 02/25/2023] Open
Abstract
BACKGROUND The left dorsolateral prefrontal cortex (DLPFC) is involved in early-phase manual dexterity skill acquisition when cognitive control processes, such as integration and complexity demands, are required. However, the effectiveness of left DLPFC transcranial direct current stimulation (tDCS) on early-phase motor learning and whether its effectiveness depends on the cognitive demand of the target task are unclear. This study aimed to investigate whether tDCS over the left DLPFC improves non-dominant hand dexterity performance and determine if its efficacy depends on the cognitive demand of the target task. METHODS In this randomized, double-blind, sham-controlled trial, 70 healthy, right-handed, young adult participants were recruited. They were randomly allocated to the active tDCS (2 mA for 20 min) or sham groups and repeatedly performed the Purdue Pegboard Test (PPT) left-handed peg task and left-handed assembly task three times: pre-tDCS, during tDCS, and post tDCS. RESULTS The final sample comprised 66 healthy young adults (mean age, 22.73 ± 1.57 years). There were significant interactions between group and time in both PPT tasks, indicating significantly higher performance of those in the active tDCS group than those in the sham group post tDCS (p < 0.001). Moreover, a greater benefit was observed in the left-handed assembly task performance than in the peg task performance (p < 0.001). No significant correlation between baseline performance and benefits from tDCS was observed in either task. CONCLUSIONS These results demonstrated that prefrontal tDCS significantly improved early-phase manual dexterity skill acquisition, and its benefits were greater for the task with high cognitive demands. These findings contribute to a deeper understanding of the underlying neurophysiological mechanisms of the left DLPFC in the modulation of early-phase dexterity skill acquisition. TRIAL REGISTRATION This study was registered in the University Hospital Medical Information Network Clinical Trial Registry in Japan (UMIN000046868), Registered February 8, 2022 https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000053467.
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Affiliation(s)
- Akihiro Watanabe
- grid.39158.360000 0001 2173 7691Graduate School of Health Sciences, Hokkaido University, Sapporo, 060-0812 Japan
| | - Daisuke Sawamura
- Department of Rehabilitation Science, Faculty of Health Sciences, Hokkaido University, Sapporo, Hokkaido, 060-0812, Japan.
| | - Hisato Nakazono
- grid.443459.b0000 0004 0374 9105Department of Occupational Therapy, Faculty of Medical Science, Fukuoka International University of Health and Welfare, Fukuoka, 814-0001 Japan
| | - Yukina Tokikuni
- grid.39158.360000 0001 2173 7691Graduate School of Health Sciences, Hokkaido University, Sapporo, 060-0812 Japan
| | - Hiroshi Miura
- grid.39158.360000 0001 2173 7691Graduate School of Health Sciences, Hokkaido University, Sapporo, 060-0812 Japan
| | - Kazuhiro Sugawara
- grid.263171.00000 0001 0691 0855Department of Physical Therapy, Sapporo Medical University, Sapporo, 060-8556 Japan
| | - Kanako Fuyama
- grid.412167.70000 0004 0378 6088Data Science Center, Promotion Unit, Institute of Health Science Innovation for Medical Care, Hokkaido University Hospital, Sapporo, 060-8648 Japan
| | - Harukazu Tohyama
- grid.39158.360000 0001 2173 7691Department of Rehabilitation Science, Faculty of Health Sciences, Hokkaido University, Sapporo, Hokkaido 060-0812 Japan
| | - Susumu Yoshida
- grid.412021.40000 0004 1769 5590Department of Rehabilitation Sciences, Health Sciences University of Hokkaido, Tobetsu, 061-0293 Japan
| | - Shinya Sakai
- grid.39158.360000 0001 2173 7691Department of Rehabilitation Science, Faculty of Health Sciences, Hokkaido University, Sapporo, Hokkaido 060-0812 Japan
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San-Juan D, Stavropoulos I, Valentin A. A New Non-invasive Neuromodulation Technique for Super Refractory Status Epilepticus: Can We Consider tDCS for This Devastating Condition? Neurotherapeutics 2023; 20:179-180. [PMID: 36484907 PMCID: PMC10119353 DOI: 10.1007/s13311-022-01329-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/30/2022] [Indexed: 12/13/2022] Open
Affiliation(s)
- Daniel San-Juan
- Epilepsy Clinic, National Institute of Neurology and Neurosurgery, Mexico City, Mexico
| | - Ioannis Stavropoulos
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
- Department Of Clinical Neurophysiology, King's College Hospital, London, UK
| | - Antonio Valentin
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
- Department Of Clinical Neurophysiology, King's College Hospital, London, UK.
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Zhang L, Xuan R, Chen Q, Zhao Q, Shi Z, Du J, Zhu C, Yu F, Ji G, Wang K. High-definition transcranial direct current stimulation modulates eye gaze on emotional faces in college students with alexithymia: An eye-tracking study. Prog Neuropsychopharmacol Biol Psychiatry 2022; 116:110521. [PMID: 35104607 DOI: 10.1016/j.pnpbp.2022.110521] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 01/21/2022] [Accepted: 01/23/2022] [Indexed: 12/21/2022]
Abstract
BACKGROUND Atypical eye gaze on emotional faces is a core feature of alexithymia. The inferior frontal gyrus (IFG) is considered to be the neurophysiological basis of alexithymia-related emotional face fixation. Our aim was to examine whether anodal high-definition transcranial direct current stimulation (HD-tDCS) administered to the right (r)IFG would facilitate eye gaze of emotional faces in alexithymia individuals. METHOD Forty individuals with alexithymia were equally assigned to anodal or sham HD-tDCS of the rIFG according to the principle of randomization. The individuals then completed a free-viewing eye tracking task (including happy, sad, and neutral faces) before and after 5 consecutive days of stimulation (twice a day). RESULTS The results showed that twice a day anodal HD-tDCS of the rIFG significantly increased the fixation time and fixation count of the eye area on happy and neutral faces, but there was no significant effect on sad faces. According to the temporal-course analysis, after the intervention, the fixation time on neutral faces increased significantly at almost all time points of the eye tracking task. For happy faces, the improvement was demonstrated between 500 and 1000 ms and between 2500 and 3500 ms. For sad faces, the fixation time improved but not significantly. CONCLUSIONS Applying high-dose anodal HD-tDCS to the rIFG selectively facilitated eye gaze in the eye area of neutral and happy faces in individuals with alexithymia, which may improve their face processing patterns.
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Affiliation(s)
- Lei Zhang
- School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei 230032, China; The Second Affiliated Hospital of Anhui Medical University, Hefei, China.
| | - Rongrong Xuan
- School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei 230032, China
| | - Qiuyu Chen
- School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei 230032, China
| | - Qingqing Zhao
- School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei 230032, China
| | - Zhulin Shi
- School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei 230032, China
| | - Jinmei Du
- School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei 230032, China
| | - Chunyan Zhu
- School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei 230032, China
| | - FengQiong Yu
- School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei 230032, China
| | - Gongjun Ji
- School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei 230032, China
| | - Kai Wang
- Department of Neurology, The First Affiliated Hospital of Anhui Medical University, The School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei 230032, Anhui Province, China; Anhui Province Key Laboratory of Cognition and Neuropsychiatric Disorders, Hefei 230032, China; Collaborative Innovation Center for Neuropsychiatric Disorders and Mental Health, Anhui Medical University, Hefei 230032, China; Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei 230088, China.
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Griffin L, Kamarunas E, Kuo C, O'Donoghue C. Comparing amplitudes of transcranial direct current stimulation (tDCS) to the sensorimotor cortex during swallowing. Exp Brain Res 2022; 240:1811-1822. [PMID: 35551431 DOI: 10.1007/s00221-022-06381-z] [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: 11/11/2021] [Accepted: 04/25/2022] [Indexed: 11/04/2022]
Abstract
PURPOSE Transcranial direct current stimulation (tDCS) can alter cortical excitability, making it a useful tool for promoting neuroplasticity in dysphagia rehabilitation. Clinical trials show functional improvements in swallowing following anodal tDCS despite varying dosing parameters and outcomes. The aim of the current study was to determine the most effective amplitude criterion (e.g., 0 mA [sham/control], 1 mA, 2 mA) of anodal tDCS for upregulating the swallowing sensorimotor cortex. METHOD As a novel paradigm, tDCS, functional near-infrared spectroscopy (fNIRS), and surface electromyography (sEMG) were simultaneously administered while participants completed a swallowing task. This allowed for measurement of the cortical hemodynamic response and submental muscle contraction before, during, and after tDCS. At the conclusion of the study, participants were asked to rate their level of discomfort associated with tDCS using a visual analog scale. RESULTS There was no significant difference in the hemodynamic response by time or amplitude. However, post-hoc analyses indicated that in the post-stimulation period, changes to the hemodynamic response in the left (stimulated) hemisphere were significantly different for the groups receiving 1 mA and 2 mA of tDCS compared to baseline. Participants receiving 1 mA of tDCS demonstrated reduced hemodynamic response. There was no significant difference in submental muscle contraction during or after tDCS regardless of amplitude. Anodal tDCS was well tolerated in healthy adults with no difference among participant discomfort scores across tDCS amplitude. CONCLUSIONS During a swallowing task, healthy volunteers receiving 1 mA of anodal tDCS demonstrated a suppressed hemodynamic response during and after stimulation whereas those receiving 2 mA of anodal tDCS had an increase in the hemodynamic response. tDCS remains a promising tool in dysphagia rehabilitation, but dosing parameters require further clarification.
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Affiliation(s)
- Lindsay Griffin
- School of Communication, Communication Sciences and Disorders, Emerson College, 120 Boylston St., Boston, MA, 02116, USA. .,College of Health and Behavioral Studies, Communication Sciences and Disorders, James Madison University, 235 Martin Luther King Jr. Way, Harrisonburg, VA, 22807, USA.
| | - Erin Kamarunas
- College of Health and Behavioral Studies, Communication Sciences and Disorders, James Madison University, 235 Martin Luther King Jr. Way, Harrisonburg, VA, 22807, USA
| | - Christina Kuo
- College of Health and Behavioral Studies, Communication Sciences and Disorders, James Madison University, 235 Martin Luther King Jr. Way, Harrisonburg, VA, 22807, USA
| | - Cynthia O'Donoghue
- College of Health and Behavioral Studies, Communication Sciences and Disorders, James Madison University, 235 Martin Luther King Jr. Way, Harrisonburg, VA, 22807, USA
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Van der Cruijsen J, Jonker ZD, Andrinopoulou ER, Wijngaarden JE, Tangkau DA, Tulen JHM, Frens MA, Ribbers GM, Selles RW. Transcranial Direct Current Stimulation Targeting the Entire Motor Network Does Not Increase Corticospinal Excitability. Front Hum Neurosci 2022; 16:842954. [PMID: 35601898 PMCID: PMC9114302 DOI: 10.3389/fnhum.2022.842954] [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] [Received: 12/24/2021] [Accepted: 04/11/2022] [Indexed: 11/21/2022] Open
Abstract
Transcranial direct current stimulation (tDCS) over the contralateral primary motor cortex of the target muscle (conventional tDCS) has been described to enhance corticospinal excitability, as measured with transcranial magnetic stimulation. Recently, tDCS targeting the brain regions functionally connected to the contralateral primary motor cortex (motor network tDCS) was reported to enhance corticospinal excitability more than conventional tDCS. We compared the effects of motor network tDCS, 2 mA conventional tDCS, and sham tDCS on corticospinal excitability in 21 healthy participants in a randomized, single-blind within-subject study design. We applied tDCS for 12 min and measured corticospinal excitability with TMS before tDCS and at 0, 15, 30, 45, and 60 min after tDCS. Statistical analysis showed that neither motor network tDCS nor conventional tDCS significantly increased corticospinal excitability relative to sham stimulation. Furthermore, the results did not provide evidence for superiority of motor network tDCS over conventional tDCS. Motor network tDCS seems equally susceptible to the sources of intersubject and intrasubject variability previously observed in response to conventional tDCS.
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Affiliation(s)
- Joris Van der Cruijsen
- Department of Rehabilitation Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
- Department of Biomechanical Engineering, Delft University of Technology, Delft, Netherlands
| | - Zeb D. Jonker
- Department of Rehabilitation Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
- Department of Neuroscience, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
- Rijndam Rehabilitation Centre, Rotterdam, Netherlands
| | - Eleni-Rosalina Andrinopoulou
- Department of Biostatistics, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
- Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Jessica E. Wijngaarden
- Department of Rehabilitation Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
- Department of Biomechanical Engineering, Delft University of Technology, Delft, Netherlands
| | - Ditte A. Tangkau
- Department of Rehabilitation Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Joke H. M. Tulen
- Department of Psychiatry, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Maarten A. Frens
- Department of Neuroscience, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Gerard M. Ribbers
- Department of Rehabilitation Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
- Rijndam Rehabilitation Centre, Rotterdam, Netherlands
| | - Ruud W. Selles
- Department of Rehabilitation Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
- Department of Plastic and Reconstructive Surgery and Hand Surgery, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
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Saporta N, Peled-Avron L, Scheele D, Lieberz J, Hurlemann R, Shamay-Tsoory SG. Touched by Loneliness - How Loneliness Impacts the Response to Observed Human Touch: a tDCS Study. Soc Cogn Affect Neurosci 2021; 17:142-150. [PMID: 34907421 PMCID: PMC8824677 DOI: 10.1093/scan/nsab122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 10/19/2021] [Accepted: 12/14/2021] [Indexed: 11/18/2022] Open
Abstract
Lonely people often crave connectedness. However, they may also experience their environment as threatening, entering a self-preserving state that perpetuates loneliness. Research shows conflicting evidence about their response to positive social cues, and little is known about their experience of observed human touch. The right inferior frontal gyrus (rIFG) is part of an observation–execution network implicated in observed touch perception. Correlative studies also point to rIFG’s involvement in loneliness. We examined the causal effect of rIFG anodal transcranial direct current stimulation on high- and low-loneliness individuals observing human touch. In a cross-over design study, 40 participants watched pictures of humans or objects touching or not touching during anodal and sham stimulations. Participants indicated whether pictures contained humans or objects, and their reaction time was measured. Results show that the reaction time of low-loneliness individuals to observed human touch was significantly slower during anodal stimulation compared to high-loneliness individuals, possibly due to them being more emotionally distracted by it. Lonely individuals also reported less liking of touch. Our findings support the notion that lonely individuals are not drawn to positive social cues. This may help explain the perpetuation of loneliness, despite social opportunities that could be available to lonely people.
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Affiliation(s)
- Nira Saporta
- School of Psychological Sciences, University of Haifa, Haifa 3498838, Israel
| | - Leehe Peled-Avron
- School of Psychological Sciences, University of Haifa, Haifa 3498838, Israel
| | - Dirk Scheele
- Division of Medical Psychology, Department of Psychiatry and Psychotherapy, University Hospital Bonn, 53105 Bonn, Germany.,Department of Psychiatry, School of Medicine & Health Sciences, University of Oldenburg, 26129 Oldenburg, Germany
| | - Jana Lieberz
- Division of Medical Psychology, Department of Psychiatry and Psychotherapy, University Hospital Bonn, 53105 Bonn, Germany
| | - René Hurlemann
- Department of Psychiatry, School of Medicine & Health Sciences, University of Oldenburg, 26129 Oldenburg, Germany.,Research Center Neurosensory Science, University of Oldenburg, 26129 Oldenburg, Germany
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12
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Suchting R, Teixeira AL, Ahn B, Colpo GD, Park J, Ahn H. Changes in Brain-derived Neurotrophic Factor From Active and Sham Transcranial Direct Current Stimulation in Older Adults With Knee Osteoarthritis. Clin J Pain 2021; 37:898-903. [PMID: 34757341 PMCID: PMC8589111 DOI: 10.1097/ajp.0000000000000987] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 09/01/2021] [Indexed: 01/08/2023]
Abstract
OBJECTIVES Previous work has shown effects of transcranial direct current stimulation (tDCS) on clinical pain measures, qualitative sensory testing measures, and peripheral inflammation. The present report extends this research to investigate the effect of tDCS on brain-derived neurotrophic factor (BDNF) levels. MATERIALS AND METHODS This secondary analysis examined a sample of 40 older adults (50 to 70 y old) with symptomatic knee osteoarthritis randomly assigned in a 1:1 fashion to active (n=20) or sham (n=20) tDCS for 20 minutes on 5 consecutive days. BDNF was measured before the first session and after the final treatment session. Generalized linear modeling evaluated BDNF plasma levels as a function of tDCS group, adjusted for baseline. Bayesian statistical inference was used to quantify the probability that effects of the treatment exist. RESULTS Generalized linear modeling indicated a 90.4% posterior probability that the sham condition had 49.9% higher BDNF at the end of treatment, controlling for baseline. Follow-up analyses within the active TDCS group supported an association between change in BDNF and change in clinical pain, and exploratory analyses found an effect of tDCS on irisin. DISCUSSION Results indicated that tDCS could be a potential nonpharmacological treatment to decrease BDNF levels, which may in turn decrease pain. This study adds to a growing literature suggesting that tDCS affects cortical excitability, and consequentially, the neural circuits implicated in pain modulation. In addition to a direct connection to analgesia, BDNF changes may reflect tDCS-induced changes in different cortical areas and/or neural circuits.
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Affiliation(s)
- Robert Suchting
- UTHealth McGovern Medical School, Faillace Department of Psychiatry and Behavioral Sciences, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Antonio L. Teixeira
- UTHealth McGovern Medical School, Faillace Department of Psychiatry and Behavioral Sciences, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Brian Ahn
- UTHealth McGovern Medical School, Faillace Department of Psychiatry and Behavioral Sciences, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Gabriela D. Colpo
- UTHealth McGovern Medical School, Faillace Department of Psychiatry and Behavioral Sciences, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Juyoung Park
- College of Social Work & Criminal Justice, Phyllis and Harvey Sandler School of Social Work, Florida Atlantic University, Boca Raton, FL, USA
| | - Hyochol Ahn
- College of Nursing, Florida State University, Tallahassee, FL, USA
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13
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Dyke K, Jackson G, Jackson S. Non-invasive brain stimulation as therapy: systematic review and recommendations with a focus on the treatment of Tourette syndrome. Exp Brain Res 2021; 240:341-363. [PMID: 34643763 PMCID: PMC8858270 DOI: 10.1007/s00221-021-06229-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 09/18/2021] [Indexed: 01/06/2023]
Abstract
Tourette syndrome (TS) is a neurodevelopmental condition characterised by tics, which are stereotyped movements and/or vocalisations. Tics often cause difficulties in daily life and many with TS express a desire to reduce and/or gain control over them. No singular effective treatment exists for TS, and while pharmacological and behavioural interventions can be effective, the results are variable, and issues relating to access, availability and side effects can be barriers to treatment. Consequently, over the past decade, there has been increasing interest into the potential benefits of non-invasive brain stimulation (NIBS) approaches. This systematic review highlights work exploring NIBS as a potential treatment for TS. On balance, the results tentatively suggest that multiple sessions of stimulation applied over the supplementary motor area (SMA) may help to reduce tics. However, a number of methodological and theoretical issues limit the strength of this conclusion, with the most problematic being the lack of large-scale sham-controlled studies. In this review, methodological and theoretical issues are discussed, unanswered questions highlighted and suggestions for future work put forward.
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Affiliation(s)
- Katherine Dyke
- School of Psychology, University of Nottingham, Nottingham, UK.
| | - Georgina Jackson
- Institute of Mental Health, School of Medicine, University of Nottingham, Nottingham, UK.,School of Medicine, The University of Nottingham, Nottingham, UK
| | - Stephen Jackson
- School of Psychology, University of Nottingham, Nottingham, UK.,Institute of Mental Health, School of Medicine, University of Nottingham, Nottingham, UK
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14
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Feasibility of combining functional near-infrared spectroscopy with electroencephalography to identify chronic stroke responders to cerebellar transcranial direct current stimulation-a computational modeling and portable neuroimaging methodological study. THE CEREBELLUM 2021; 20:853-871. [PMID: 33675516 DOI: 10.1007/s12311-021-01249-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/21/2021] [Indexed: 10/22/2022]
Abstract
Feasibility of portable neuroimaging of cerebellar transcranial direct current stimulation (ctDCS) effects on the cerebral cortex has not been investigated vis-à-vis cerebellar lobular electric field strength. We studied functional near-infrared spectroscopy (fNIRS) in conjunction with electroencephalography (EEG) to measure changes in the brain activation at the prefrontal cortex (PFC) and the sensorimotor cortex (SMC) following ctDCS as well as virtual reality-based balance training (VBaT) before and after ctDCS treatment in 12 hemiparetic chronic stroke survivors. We performed general linear modeling (GLM) that putatively associated the lobular electric field strength with the changes in the fNIRS-EEG measures at the ipsilesional and contra-lesional PFC and SMC. Here, fNIRS-EEG measures were found in the latent space from canonical correlation analysis (CCA) between the changes in total hemoglobin (tHb) concentrations (0.01-0.07Hz and 0.07-0.13Hz bands) and log10-transformed EEG bandpower within 1-45 Hz where significant (Wilks' lambda>0.95) canonical correlations were found only for the 0.07-0.13-Hz band. Also, the first principal component (97.5% variance accounted for) of the mean lobular electric field strength was a good predictor of the latent variables of oxy-hemoglobin (O2Hb) concentrations and log10-transformed EEG bandpower. GLM also provided insights into non-responders to ctDCS who also performed poorly in the VBaT due to ideomotor apraxia. Future studies should investigate fNIRS-EEG joint-imaging in a larger cohort to identify non-responders based on GLM fitting to the fNIRS-EEG data.
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15
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Ammann C, Guida P, Caballero-Insaurriaga J, Pineda-Pardo JA, Oliviero A, Foffani G. A framework to assess the impact of number of trials on the amplitude of motor evoked potentials. Sci Rep 2020; 10:21422. [PMID: 33293541 PMCID: PMC7722939 DOI: 10.1038/s41598-020-77383-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 10/30/2020] [Indexed: 12/12/2022] Open
Abstract
The amplitude of motor evoked potentials (MEPs) elicited by transcranial magnetic stimulation (TMS) is a common yet highly variable measure of corticospinal excitability. The tradeoff between maximizing the number of trials and minimizing experimental time remains a hurdle. It is therefore important to establish how many trials should be used. The aim of this study is not to provide rule-of-thumb answers that may be valid only in specific experimental conditions, but to offer a more general framework to inform the decision about how many trials to use under different experimental conditions. Specifically, we present a set of equations that show how the number of trials affects single-subject MEP amplitude, population MEP amplitude, hypothesis testing and test-retest reliability, depending on the variability within and between subjects. The equations are derived analytically, validated with Monte Carlo simulations, and representatively applied to experimental data. Our findings show that the minimum number of trials for estimating single-subject MEP amplitude largely depends on the experimental conditions and on the error considered acceptable by the experimenter. Conversely, estimating population MEP amplitude and hypothesis testing are markedly more dependent on the number of subjects than on the number of trials. These tools and results help to clarify the impact of the number of trials in the design and reproducibility of past and future experiments.
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Affiliation(s)
- Claudia Ammann
- HM CINAC, Hospital Universitario HM Puerta del Sur, HM Hospitales, Universidad CEU-San Pablo, Madrid, Spain
- CIBERNED, Instituto de Salud Carlos III, Madrid, Spain
| | - Pasqualina Guida
- HM CINAC, Hospital Universitario HM Puerta del Sur, HM Hospitales, Universidad CEU-San Pablo, Madrid, Spain
| | | | - José A Pineda-Pardo
- HM CINAC, Hospital Universitario HM Puerta del Sur, HM Hospitales, Universidad CEU-San Pablo, Madrid, Spain
- CIBERNED, Instituto de Salud Carlos III, Madrid, Spain
| | | | - Guglielmo Foffani
- HM CINAC, Hospital Universitario HM Puerta del Sur, HM Hospitales, Universidad CEU-San Pablo, Madrid, Spain.
- CIBERNED, Instituto de Salud Carlos III, Madrid, Spain.
- Hospital Nacional de Parapléjicos, Toledo, Spain.
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16
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Papasavvas CA, Schroeder GM, Diehl B, Baier G, Taylor PN, Wang Y. Band power modulation through intracranial EEG stimulation and its cross-session consistency. J Neural Eng 2020; 17:054001. [PMID: 33022661 PMCID: PMC7612301 DOI: 10.1088/1741-2552/abbecf] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Direct electrical stimulation of the brain through intracranial electrodes is currently used to probe the epileptic brain as part of pre-surgical evaluation, and it is also being considered for therapeutic treatments through neuromodulation. In order to effectively modulate neural activity, a given neuromodulation design must elicit similar responses throughout the course of treatment. However, it is unknown whether intracranial electrical stimulation responses are consistent across sessions. The objective of this study was to investigate the within-subject, cross-session consistency of the electrophysiological effect of electrical stimulation delivered through intracranial electroencephalography (iEEG). APPROACH We analysed data from 79 epilepsy patients implanted with iEEG who underwent brain stimulation as part of a memory experiment. We quantified the effect of stimulation in terms of band power modulation and compared this effect from session to session. As a reference, we made the same measurements during baseline periods. MAIN RESULTS In most sessions, the effect of stimulation on band power could not be distinguished from baseline fluctuations of band power. Stimulation effect was consistent in a third of the session pairs, while the rest had a consistency measure not exceeding the baseline standards. Cross-session consistency was highly correlated with the degree of band power increase, and it also tended to be higher when the baseline conditions were more similar between sessions. SIGNIFICANCE These findings can inform our practices for designing neuromodulation with greater efficacy when using direct electrical brain stimulation as a therapeutic treatment.
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Affiliation(s)
- Christoforos A Papasavvas
- CNNP Lab (www.cnnp-lab.com), Interdisciplinary Computing and Complex BioSystems Group, School of Computing, Newcastle University, Newcastle upon Tyne, United Kingdom
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17
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Pellegrini M, Zoghi M, Jaberzadeh S. A Checklist to Reduce Response Variability in Studies Using Transcranial Magnetic Stimulation for Assessment of Corticospinal Excitability: A Systematic Review of the Literature. Brain Connect 2020; 10:53-71. [PMID: 32093486 DOI: 10.1089/brain.2019.0715] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Response variability between individuals (interindividual variability) and within individuals (intraindividual variability) is an important issue in the transcranial magnetic stimulation (TMS) literature. This has raised questions of the validity of TMS to assess changes in corticospinal excitability (CSE) in a predictable and reliable manner. Several participant-specific factors contribute to this observed response variability with a current lack of consensus on the degree each factor contributes. This highlights a need for consistency and structure in reporting study designs and methodologies. Currently, there is no summarized review of the participant-specific factors that can be controlled and may contribute to response variability. This systematic review aimed to develop a checklist of methodological measures taken by previously published research to increase the homogeneity of participant selection criteria, preparation of participants before experimental testing, participant scheduling, and the instructions given to participants throughout experimental testing to minimize their effect on response variability. Seven databases were searched in full. Studies were included if CSE was measured via TMS and included methodological measures to increase the homogeneity of the participants. Eighty-four studies were included. Twenty-three included measures to increase participant selection homogeneity, 21 included measures to increase participant preparation homogeneity, while 61 included measures to increase participant scheduling and instructions during experimental testing homogeneity. These methodological measures were summarized into a user-friendly checklist with considerations, suggestions, and rationale/justification for their inclusion. This may provide the framework for further insights into ways to reduce response variability in TMS research.
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Affiliation(s)
- Michael Pellegrini
- Non-Invasive Brain Stimulation and Neuroplasticity Laboratory, Department of Physiotherapy, School of Primary and Allied Health Care, Faculty of Medicine, Nursing and Health Science, Monash University, Melbourne, Victoria, Australia
| | - Maryam Zoghi
- Department of Rehabilitation, Nutrition and Sport, Discipline of Physiotherapy, School of Allied Health, La Trobe University, Melbourne, Victoria, Australia
| | - Shapour Jaberzadeh
- Non-Invasive Brain Stimulation and Neuroplasticity Laboratory, Department of Physiotherapy, School of Primary and Allied Health Care, Faculty of Medicine, Nursing and Health Science, Monash University, Melbourne, Victoria, Australia
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18
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Wagner J, Lo Monaco S, Contò F, Parrott D, Battelli L, Rusconi E. Effects of transcranial direct current stimulation over the posterior parietal cortex on novice X-ray screening performance. Cortex 2020; 132:1-14. [PMID: 32911230 DOI: 10.1016/j.cortex.2020.08.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 07/08/2020] [Accepted: 08/03/2020] [Indexed: 10/23/2022]
Abstract
Existing theories of visual search are generally deduced from lab-based studies involving the identification of a target object among similar distractors. The role of the right parietal cortex in visual search is well-established. However, less is known about real-world visual search tasks, such as X-ray screening, which require targets to be disembedded from their background. Research has shown variations in the cognitive abilities required for these tasks and typical lab-based visual search tasks. Thus, the findings of traditional visual search studies do not always transfer into the applied domain. Although brain imaging studies have offered insights into visual search tasks involving disembedding, highlighting an association between the left parietal cortex and disembedding performance, no causal link has yet been established. To this end, we carried out a pilot study (n = 34, between-subjects) administering non-invasive brain stimulation over the posterior parietal cortex (PPC) prior to completing a security X-ray screening task. The findings suggested that anodal left PPC tDCS enhanced novice performance in X-ray screening over that of sham stimulation, in line with brain imaging findings. However, the efficacy of tDCS is under question, with a growing number of failed replications. With this in mind, this study aims to re-test our original hypothesis by examining the effects of left-side parietal stimulation on novice X-ray screener performance and comparing them to those of sham stimulation and of stimulation on a control site (right PPC). As such, this within-subjects study comprised three sessions (2 mA left PPC, 2 mA right PPC, low-intensity sham stimulation left PPC), to investigate effects of anodal tDCS on X-ray screening performance. The pre-registered analysis did not detect any significant differences between left PPC tDCS and sham tDCS or left PPC tDCS and right PPC tDCS on novice performance (d') in X-ray screening. Further exploratory analyses detected no effects of left PPC tDCS on any other indices of performance in the X-ray security screening task (c, RTs and accuracy), or a disembedding control task (RTs and accuracy). The use of alternative stimulation techniques, with replicable behavioural effects on the parietal lobe (or a multi-technique approach), and well-powered studies with a systematic variation of stimulation parameters, could help to choose between two possible interpretations: that neither left nor right PPC are causally related to either tasks or that tDCS was ineffective. Finally, low-intensity sham stimulation (.016 mA), previously shown to outperform other sham conditions in between-subjects designs, was found to be ineffective for blinding participants in a within-subjects design. Our findings raise concerns for the current lack of optimal control conditions and add to the growing literature highlighting the need for replication in the field.
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Affiliation(s)
| | - Silvia Lo Monaco
- Department of Psychology and Cognitive Sciences, University of Trento, Rovereto, Italy
| | - Federica Contò
- Center for Neuroscience and Cognitive Systems@UniTn, Istituto Italiano di Tecnologia, Rovereto, Italy
| | - Danielle Parrott
- Center for Neuroscience and Cognitive Systems@UniTn, Istituto Italiano di Tecnologia, Rovereto, Italy
| | - Lorella Battelli
- Center for Neuroscience and Cognitive Systems@UniTn, Istituto Italiano di Tecnologia, Rovereto, Italy; Department of Neurology, Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, USA
| | - Elena Rusconi
- Department of Psychology and Cognitive Sciences, University of Trento, Rovereto, Italy.
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19
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Galli G, Miniussi C, Pellicciari MC. Transcranial electric stimulation as a neural interface to gain insight on human brain functions: current knowledge and future perspective. Soc Cogn Affect Neurosci 2020; 17:4-14. [PMID: 32756871 DOI: 10.1093/scan/nsaa099] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 05/12/2020] [Accepted: 07/11/2020] [Indexed: 11/12/2022] Open
Abstract
The use of brain-stimulation approaches in social and affective science has greatly increased over the last two decades. The interest in social factors has grown along with technological advances in brain research. Transcranial electric stimulation (tES) is a research tool that allows scientists to establish contributory causality between brain functioning and social behaviour, therefore deepening our understanding of the social mind. Preliminary evidence is also starting to demonstrate that tES, either alone or in combination with pharmacological or behavioural interventions, can alleviate the symptomatology of individuals with affective or social cognition disorders. This review offers an overview of the application of tES in the field of social and affective neuroscience. We discuss issues and challenges related to this application and suggest avenue for future basic and translational research.
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Affiliation(s)
- Giulia Galli
- Department of Psychology, Kingston University, Penrhyn Road, Kingston Upon Thames, KT1 2EE, United Kingdom
| | - Carlo Miniussi
- Center for Mind/Brain Sciences - CIMeC, University of Trento, Corso Bettini, 31, 38068 Rovereto, TN Italy
| | - Maria Concetta Pellicciari
- UniCamillus - Saint Camillus International University of Health Sciences, via di Sant'Alessandro 8, 00131, Rome, Italy
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20
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Liao WW, Chiang WC, Lin KC, Wu CY, Liu CT, Hsieh YW, Lin YC, Chen CL. Timing-dependent effects of transcranial direct current stimulation with mirror therapy on daily function and motor control in chronic stroke: a randomized controlled pilot study. J Neuroeng Rehabil 2020; 17:101. [PMID: 32690032 PMCID: PMC7370428 DOI: 10.1186/s12984-020-00722-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 07/06/2020] [Indexed: 02/07/2023] Open
Abstract
Background The timing of transcranial direct current stimulation (tDCS) with neurorehabilitation interventions may affect its modulatory effects. Motor function has been reported to be modulated by the timing of tDCS; however, whether the timing of tDCS would also affect restoration of daily function and upper extremity motor control with neurorehabilitation in stroke patients remains largely unexplored. Mirror therapy (MT) is a potentially effective neurorehabilitation approach for improving paretic arm function in stroke patients. This study aimed to determine whether the timing of tDCS with MT would influence treatment effects on daily function, motor function and motor control in individuals with chronic stroke. Methods This study was a double-blinded randomized controlled trial. Twenty-eight individuals with chronic stroke received one of the following three interventions: (1) sequentially combined tDCS with MT (SEQ), (2) concurrently combined tDCS with MT (CON), and (3) sham tDCS with MT (SHAM). Participants received interventions for 90 min/day, 5 days/week for 4 weeks. Daily function was assessed using the Nottingham Extended Activities of Daily Living Scale. Upper extremity motor function was assessed using the Fugl-Meyer Assessment Scale. Upper extremity motor control was evaluated using movement kinematic assessments. Results There were significant differences in daily function between the three groups. The SEQ group had greater improvement in daily function than the CON and SHAM groups. Kinematic analyses showed that movement time of the paretic hand significantly reduced in the SEQ group after interventions. All three groups had significant improvement in motor function from pre-intervention to post-intervention. Conclusion The timing of tDCS with MT may influence restoration of daily function and movement efficiency of the paretic hand in chronic stroke patients. Sequentially applying tDCS prior to MT seems to be advantageous for enhancing daily function and hand movement control, and may be considered as a potentially useful strategy in future clinical application. Trial registration ClinicalTrials.gov Identifier: NCT02827864. Registered on 29th June, 2016.
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Affiliation(s)
- Wan-Wen Liao
- Department of Occupational Therapy and Graduate Institute of Behavioral Sciences, College of Medicine, Chang Gung University, 259 Wen-hwa 1st Road, Taoyuan City, Taiwan
| | - Wei-Chi Chiang
- Department of Occupational Therapy, I-Shou University, Kaohsiung, Taiwan
| | - Keh-Chung Lin
- School of Occupational Therapy, College of Medicine, National Taiwan University, Taipei, Taiwan.,Division of Occupational Therapy, Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, Taipei, Taiwan
| | - Ching-Yi Wu
- Department of Occupational Therapy and Graduate Institute of Behavioral Sciences, College of Medicine, Chang Gung University, 259 Wen-hwa 1st Road, Taoyuan City, Taiwan. .,Healthy Aging Research Center, Chang Gung University, Taoyuan, Taiwan. .,Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, Linkou, Taiwan.
| | - Chien-Ting Liu
- Department of Rehabilitation, Taipei Tzu Chi Hospital, The Buddhist Tzu-Chi Medical Foundation, Taipei, Taiwan
| | - Yu-Wei Hsieh
- Department of Occupational Therapy and Graduate Institute of Behavioral Sciences, College of Medicine, Chang Gung University, 259 Wen-hwa 1st Road, Taoyuan City, Taiwan.,Healthy Aging Research Center, Chang Gung University, Taoyuan, Taiwan.,Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, Linkou, Taiwan
| | - Yun-Chung Lin
- Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Chia-Ling Chen
- Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, Linkou, Taiwan.,Graduate Institute of Early Intervention, College of Medicine, Chang Gung University, Taoyuan, Taiwan
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21
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Coulborn S, Bowman H, Miall RC, Fernández-Espejo D. Effect of tDCS Over the Right Inferior Parietal Lobule on Mind-Wandering Propensity. Front Hum Neurosci 2020; 14:230. [PMID: 32655387 PMCID: PMC7325883 DOI: 10.3389/fnhum.2020.00230] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 05/25/2020] [Indexed: 12/21/2022] Open
Abstract
Mind-wandering is associated with switching our attention to internally directed thoughts and is by definition an intrinsic, self-generated cognitive function. Interestingly, previous research showed that it may be possible to modulate its propensity externally, with transcranial direct current stimulation (tDCS) targeting different regions in the default mode and executive control networks (ECNs). However, these studies used highly heterogeneous montages (targeting the dorsolateral prefrontal cortex (DLPFC), the right inferior parietal lobule (IPL), or both concurrently), often showed contradicting results, and in many cases failed to replicate. Our study aimed to establish whether tDCS of the default mode network (DMN), via targeting the right IPL alone, could modulate mind-wandering propensity using a within-subjects double-blind, counterbalanced design. Participants completed sustained attention to response task (SART) interspersed with thought-probes to capture their subjective reports of mind-wandering before and after receiving anodal, cathodal, or sham tDCS over the right IPL (with the reference over the left cheek). We found evidence for the lack of an effect of stimulation on subjective reports of mind-wandering (JZS-BF01 = 5.19), as well as on performance on the SART task (errors (JZS-BF01 = 6.79) and reaction time (JZS-BF01 = 5.94). Overall, we failed to replicate previous reports of successful modulations of mind-wandering propensity with tDCS over the IPL, instead of providing evidence in support of the lack of an effect. This and other recent unsuccessful replications call into question whether it is indeed possible to externally modulate spontaneous or self-generated cognitive processes.
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Affiliation(s)
- Sean Coulborn
- School of Psychology, University of Birmingham, Birmingham, United Kingdom.,Centre for Human Brain Health, University of Birmingham, Birmingham, United Kingdom
| | - Howard Bowman
- School of Psychology, University of Birmingham, Birmingham, United Kingdom.,Centre for Human Brain Health, University of Birmingham, Birmingham, United Kingdom
| | - R Chris Miall
- School of Psychology, University of Birmingham, Birmingham, United Kingdom.,Centre for Human Brain Health, University of Birmingham, Birmingham, United Kingdom
| | - Davinia Fernández-Espejo
- School of Psychology, University of Birmingham, Birmingham, United Kingdom.,Centre for Human Brain Health, University of Birmingham, Birmingham, United Kingdom
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22
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Esmaeilpour Z, Shereen AD, Ghobadi‐Azbari P, Datta A, Woods AJ, Ironside M, O'Shea J, Kirk U, Bikson M, Ekhtiari H. Methodology for tDCS integration with fMRI. Hum Brain Mapp 2020; 41:1950-1967. [PMID: 31872943 PMCID: PMC7267907 DOI: 10.1002/hbm.24908] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 11/09/2019] [Accepted: 12/10/2019] [Indexed: 12/28/2022] Open
Abstract
Understanding and reducing variability of response to transcranial direct current stimulation (tDCS) requires measuring what factors predetermine sensitivity to tDCS and tracking individual response to tDCS. Human trials, animal models, and computational models suggest structural traits and functional states of neural systems are the major sources of this variance. There are 118 published tDCS studies (up to October 1, 2018) that used fMRI as a proxy measure of neural activation to answer mechanistic, predictive, and localization questions about how brain activity is modulated by tDCS. FMRI can potentially contribute as: a measure of cognitive state-level variance in baseline brain activation before tDCS; inform the design of stimulation montages that aim to target functional networks during specific tasks; and act as an outcome measure of functional response to tDCS. In this systematic review, we explore methodological parameter space of tDCS integration with fMRI spanning: (a) fMRI timing relative to tDCS (pre, post, concurrent); (b) study design (parallel, crossover); (c) control condition (sham, active control); (d) number of tDCS sessions; (e) number of follow up scans; (f) stimulation dose and combination with task; (g) functional imaging sequence (BOLD, ASL, resting); and (h) additional behavioral (cognitive, clinical) or quantitative (neurophysiological, biomarker) measurements. Existing tDCS-fMRI literature shows little replication across these permutations; few studies used comparable study designs. Here, we use a representative sample study with both task and resting state fMRI before and after tDCS in a crossover design to discuss methodological confounds. We further outline how computational models of current flow should be combined with imaging data to understand sources of variability. Through the representative sample study, we demonstrate how modeling and imaging methodology can be integrated for individualized analysis. Finally, we discuss the importance of conducting tDCS-fMRI with stimulation equipment certified as safe to use inside the MR scanner, and of correcting for image artifacts caused by tDCS. tDCS-fMRI can address important questions on the functional mechanisms of tDCS action (e.g., target engagement) and has the potential to support enhancement of behavioral interventions, provided studies are designed rationally.
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Affiliation(s)
- Zeinab Esmaeilpour
- Neural Engineering Laboratory, Department of Biomedical EngineeringThe City College of the City University of New York, City College Center for Discovery and InnovationNew YorkNew York
| | - A. Duke Shereen
- Advanced Science Research Center, The Graduate CenterCity University of New YorkNew YorkNew York
| | | | | | - Adam J. Woods
- Center for Cognitive Aging and Memory, McKnight Brain Institute, Department of Clinical and Health PsychologyUniversity of FloridaGainesvilleFlorida
| | - Maria Ironside
- Center for Depression, Anxiety and Stress Research, McLean HospitalBelmontMassachusetts
- Department of PsychiatryHarvard Medical SchoolBostonMassachusetts
| | - Jacinta O'Shea
- Nuffield Department of Clinical Neuroscience, Medical Science DivisionUniversity of OxfordOxfordEnglandUK
| | - Ulrich Kirk
- Department of PsychologyUniversity of Southern DenmarkOdenseDenmark
| | - Marom Bikson
- Neural Engineering Laboratory, Department of Biomedical EngineeringThe City College of the City University of New York, City College Center for Discovery and InnovationNew YorkNew York
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Gibson BC, Mullins TS, Heinrich MD, Witkiewitz K, Yu AB, Hansberger JT, Clark VP. Transcranial direct current stimulation facilitates category learning. Brain Stimul 2020; 13:393-400. [DOI: 10.1016/j.brs.2019.11.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 11/06/2019] [Accepted: 11/20/2019] [Indexed: 10/25/2022] Open
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24
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Guerra A, López-Alonso V, Cheeran B, Suppa A. Variability in non-invasive brain stimulation studies: Reasons and results. Neurosci Lett 2020; 719:133330. [DOI: 10.1016/j.neulet.2017.12.058] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 12/18/2017] [Accepted: 12/27/2017] [Indexed: 01/22/2023]
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25
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Evans C, Bachmann C, Lee JS, Gregoriou E, Ward N, Bestmann S. Dose-controlled tDCS reduces electric field intensity variability at a cortical target site. Brain Stimul 2020; 13:125-136. [DOI: 10.1016/j.brs.2019.10.004] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Revised: 08/26/2019] [Accepted: 10/03/2019] [Indexed: 01/30/2023] Open
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Effects of single-session cathodal transcranial direct current stimulation on tic symptoms in Tourette's syndrome. Exp Brain Res 2019; 237:2853-2863. [PMID: 31463531 PMCID: PMC6794240 DOI: 10.1007/s00221-019-05637-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 08/19/2019] [Indexed: 11/27/2022]
Abstract
Tourette syndrome is a neurodevelopmental disorder characterised by motor and phonic tics. For some, tics can be managed using medication and/or forms of behavioural therapy; however, adverse side effects and access to specialist resources can be barriers to treatment. In this sham-controlled brain stimulation study, we investigated the effects of transcranial direct current stimulation (tDCS) on the occurrence of tics and motor cortical excitability in individuals aged 16–33 years with Tourette syndrome. Changes in tics were measured using video recordings scored using the RUSH method (Goetz et al. in Mov Disord 14:502–506, 1999) and changes in cortical excitability were measured using single-pulse transcranial magnetic stimulation (spTMS) over the primary motor cortex (M1). Video recordings and spTMS measures were taken before and after 20 min of sham or active tDCS: during which cathodal current was delivered to an electrode placed above the supplementary motor area (SMA). Tic impairment scores, calculated from the video data, were significantly lower post-cathodal stimulation in comparison with post-sham stimulation; however, the interaction between time (pre/post) and stimulation (cathodal/sham) was not significant. There was no indication of a statistically significant change in M1 cortical excitability following SMA stimulation. This study presents tentative evidence that tDCS may be helpful in reducing tics for some individuals, and provides a foundation for larger scale explorations of the use of tDCS as a treatment for reducing tics.
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He Q, Lin BR, Zhao J, Shi YZ, Yan FF, Huang CB. No effects of anodal transcranial direct current stimulation on contrast sensitivity function. Restor Neurol Neurosci 2019; 37:109-118. [DOI: 10.3233/rnn-180881] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Qing He
- Key Laboratory of Behavioral Sciences, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
| | - Bo-Rong Lin
- Key Laboratory of Behavioral Sciences, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
| | - Jin Zhao
- Key Laboratory of Behavioral Sciences, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
| | - Ying-Zhen Shi
- Key Laboratory of Behavioral Sciences, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
| | - Fang-Fang Yan
- Key Laboratory of Behavioral Sciences, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
| | - Chang-Bing Huang
- Key Laboratory of Behavioral Sciences, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
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Miyaguchi S, Otsuru N, Kojima S, Yokota H, Saito K, Inukai Y, Onishi H. The effect of gamma tACS over the M1 region and cerebellar hemisphere does not depend on current intensity. J Clin Neurosci 2019; 65:54-58. [PMID: 30954355 DOI: 10.1016/j.jocn.2019.03.045] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 03/25/2019] [Indexed: 01/29/2023]
Abstract
Transcranial alternating current stimulation (tACS) has been shown to modulate neural connectivity in the cortical area under experimental electrodes. Although gamma tACS over the M1 region and the cerebellar hemisphere has been shown to improve motor performance, the optimal stimulation method has not been clarified. In this study, we aimed to clarify whether the effect of gamma tACS over M1 and the cerebellar hemisphere depends on current intensity. Twenty healthy adults performed a visuomotor control task using their right index finger for 30 s during tACS (70 Hz) over the left M1 and the right cerebellar hemisphere. Each subject participated in 10 trials, separated by intervals of 3 min. Three stimulation conditions were applied: (1) pseudo-stimulation (sham condition), (2) tACS with a current intensity of 1.0 mA and (3) tACS with a current intensity of 2.0 mA. Our results indicated that regardless of the current intensity, participants with the lower motor performance had better motor performance under both tACS conditions. Such a correlation was not observed under the sham condition. Collectively, our findings demonstrated that the effect of gamma tACS over M1 and the cerebellar hemisphere does not depend on current intensity, and that motor performance slightly improved in both tACS conditions for participants with lower motor performance.
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Affiliation(s)
- Shota Miyaguchi
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Japan.
| | - Naofumi Otsuru
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Japan
| | - Sho Kojima
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Japan
| | - Hirotake Yokota
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Japan
| | - Kei Saito
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Japan
| | - Yasuto Inukai
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Japan
| | - Hideaki Onishi
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Japan
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Rabipour S, Vidjen PS, Remaud A, Davidson PSR, Tremblay F. Examining the Interactions Between Expectations and tDCS Effects on Motor and Cognitive Performance. Front Neurosci 2019; 12:999. [PMID: 30666182 PMCID: PMC6330301 DOI: 10.3389/fnins.2018.00999] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 12/11/2018] [Indexed: 11/13/2022] Open
Abstract
Background: Despite a growing literature and commercial market, the effectiveness of transcranial direct current stimulation (tDCS) remains questionable. Notably, studies rarely examine factors such as expectations of outcomes, which may influence tDCS response through placebo-like effects. Here we sought to determine whether expectations could influence the behavioral outcomes of a tDCS intervention. Methods: Through an initial study and self-replication, we recruited 121 naïve young adults 18-34 years of age (M = 21.14, SD = 3.58; 88 women). We evaluated expectations of tDCS and of motor and cognitive performance at three times: (i) at baseline; (ii) after being primed to have High or Low expectations of outcomes; and (iii) after a single session of sham-controlled anodal tDCS over the left or right motor cortex. Before and after stimulation, participants performed the Grooved Pegboard Test and a choice reaction time task as measures of motor dexterity, response time, and response inhibition. Results: Repeated measures ANOVA revealed that participants had varying, largely uncertain, expectations regarding tDCS effectiveness at baseline. Expectation ratings significantly increased or decreased in response to High or Low priming, respectively, and decreased following the intervention. Response times and accuracy on motor and cognitive measures were largely unaffected by expectation or stimulation conditions. Overall, our analysis revealed no effect attributable to baseline expectations, belief of group assignment, or experimental condition on behavioral outcomes. Subjective experience did not differ based on expectation or stimulation condition. Conclusions: Our results suggest no clear effects of tDCS or of expectations on our performance measures, highlighting the need for further investigations of such stimulation methods.
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Affiliation(s)
- Sheida Rabipour
- School of Psychology, University of Ottawa, Ottawa, ON, Canada
| | | | - Anthony Remaud
- Bruyère Research Institute, Bruyère Continuing Care, Ottawa, ON, Canada
| | - Patrick S. R. Davidson
- School of Psychology, University of Ottawa, Ottawa, ON, Canada
- Bruyère Research Institute, Bruyère Continuing Care, Ottawa, ON, Canada
| | - François Tremblay
- Bruyère Research Institute, Bruyère Continuing Care, Ottawa, ON, Canada
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Fonteneau C, Mondino M, Arns M, Baeken C, Bikson M, Brunoni AR, Burke MJ, Neuvonen T, Padberg F, Pascual-Leone A, Poulet E, Ruffini G, Santarnecchi E, Sauvaget A, Schellhorn K, Suaud-Chagny MF, Palm U, Brunelin J. Sham tDCS: A hidden source of variability? Reflections for further blinded, controlled trials. Brain Stimul 2019; 12:668-673. [PMID: 30639235 DOI: 10.1016/j.brs.2018.12.977] [Citation(s) in RCA: 113] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 12/20/2018] [Accepted: 12/29/2018] [Indexed: 11/26/2022] Open
Abstract
Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique increasingly used to modulate neural activity in the living brain. In order to establish the neurophysiological, cognitive or clinical effects of tDCS, most studies compare the effects of active tDCS to those observed with a sham tDCS intervention. In most cases, sham tDCS consists in delivering an active stimulation for a few seconds to mimic the sensations observed with active tDCS and keep participants blind to the intervention. However, to date, sham-controlled tDCS studies yield inconsistent results, which might arise in part from sham inconsistencies. Indeed, a multiplicity of sham stimulation protocols is being used in the tDCS research field and might have different biological effects beyond the intended transient sensations. Here, we seek to enlighten the scientific community to this possible confounding factor in order to increase reproducibility of neurophysiological, cognitive and clinical tDCS studies.
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Affiliation(s)
- Clara Fonteneau
- INSERM U1028, CNRS UMR5292, Lyon Neuroscience Research Center, Psychiatric Disorders: from Resistance to Response Team, F-69000, France; University Lyon 1, Villeurbanne, F-69000, France; Centre Hospitalier Le Vinatier, Lyon, F-69000, France
| | - Marine Mondino
- INSERM U1028, CNRS UMR5292, Lyon Neuroscience Research Center, Psychiatric Disorders: from Resistance to Response Team, F-69000, France; University Lyon 1, Villeurbanne, F-69000, France; Centre Hospitalier Le Vinatier, Lyon, F-69000, France
| | - Martijn Arns
- neuroCare Group GmbH, Munich, Germany; Research Institute Brainclinics, Nijmegen, the Netherlands
| | - 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
| | - Marom Bikson
- Department of Biomedical Engineering, The City College of New York, New York City, NY, USA
| | - Andre R Brunoni
- Department of Psychiatry and Psychotherapy, University Hospital, LMU, Munich, Germany; Service of Interdisciplinary Neuromodulation (SIN), Laboratory of Neuroscience (LIM27) and National Institute of Biomarkers in Neuropsychiatry (INBioN), Department and Institute of Psychiatry, University of São Paulo Medical School, São Paulo, Brazil
| | - Matthew J Burke
- Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
| | | | - Frank Padberg
- Department of Psychiatry and Psychotherapy, University Hospital, LMU, Munich, Germany
| | - Alvaro Pascual-Leone
- Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
| | - Emmanuel Poulet
- INSERM U1028, CNRS UMR5292, Lyon Neuroscience Research Center, Psychiatric Disorders: from Resistance to Response Team, F-69000, France; University Lyon 1, Villeurbanne, F-69000, France; Centre Hospitalier Le Vinatier, Lyon, F-69000, France
| | - Giulio Ruffini
- Neuroelectrics Corporation, 210 Broadway, 02139, Cambridge, MA, USA
| | - Emiliano Santarnecchi
- Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
| | - Anne Sauvaget
- CHU de Nantes, Psychiatric Neuromodulation Unit, Addictology and Liaison-Psychiatry Department, Nantes, France; Laboratory "Movement, Interactions, Performance" (E.A. 4334), Faculty of Sport Sciences, University of Nantes, Nantes, France
| | | | - Marie-Françoise Suaud-Chagny
- INSERM U1028, CNRS UMR5292, Lyon Neuroscience Research Center, Psychiatric Disorders: from Resistance to Response Team, F-69000, France; University Lyon 1, Villeurbanne, F-69000, France; Centre Hospitalier Le Vinatier, Lyon, F-69000, France
| | - Ulrich Palm
- Department of Psychiatry and Psychotherapy, University Hospital, LMU, Munich, Germany
| | - Jérome Brunelin
- INSERM U1028, CNRS UMR5292, Lyon Neuroscience Research Center, Psychiatric Disorders: from Resistance to Response Team, F-69000, France; University Lyon 1, Villeurbanne, F-69000, France; Centre Hospitalier Le Vinatier, Lyon, F-69000, France.
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31
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Gibson BC, Sanguinetti JL, Badran BW, Yu AB, Klein EP, Abbott CC, Hansberger JT, Clark VP. Increased Excitability Induced in the Primary Motor Cortex by Transcranial Ultrasound Stimulation. Front Neurol 2018; 9:1007. [PMID: 30546342 PMCID: PMC6280333 DOI: 10.3389/fneur.2018.01007] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 11/07/2018] [Indexed: 12/29/2022] Open
Abstract
Background: Transcranial Ultrasound Stimulation (tUS) is an emerging technique that uses ultrasonic waves to noninvasively modulate brain activity. As with other forms of non-invasive brain stimulation (NIBS), tUS may be useful for altering cortical excitability and neuroplasticity for a variety of research and clinical applications. The effects of tUS on cortical excitability are still unclear, and further complications arise from the wide parameter space offered by various types of devices, transducer arrangements, and stimulation protocols. Diagnostic ultrasound imaging devices are safe, commonly available systems that may be useful for tUS. However, the feasibility of modifying brain activity with diagnostic tUS is currently unknown. Objective: We aimed to examine the effects of a commercial diagnostic tUS device using an imaging protocol on cortical excitability. We hypothesized that imaging tUS applied to motor cortex could induce changes in cortical excitability as measured using a transcranial magnetic stimulation (TMS) motor evoked potential (MEP) paradigm. Methods: Forty-three subjects were assigned to receive either verum (n = 21) or sham (n = 22) diagnostic tUS in a single-blind design. Baseline motor cortex excitability was measured using MEPs elicited by TMS. Diagnostic tUS was subsequently administered to the same cortical area for 2 min, immediately followed by repeated post-stimulation MEPs recorded up to 16 min post-stimulation. Results: Verum tUS increased excitability in the motor cortex (from baseline) by 33.7% immediately following tUS (p = 0.009), and 32.4% (p = 0.047) 6 min later, with excitability no longer significantly different from baseline by 11 min post-stimulation. By contrast, subjects receiving sham tUS showed no significant changes in MEP amplitude. Conclusion: These findings demonstrate that tUS delivered via a commercially available diagnostic imaging ultrasound system transiently increases excitability in the motor cortex as measured by MEPs. Diagnostic tUS devices are currently used for internal imaging in many health care settings, and the present results suggest that these same devices may also offer a promising tool for noninvasively modulating activity in the central nervous system. Further studies exploring the use of diagnostic imaging devices for neuromodulation are warranted.
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Affiliation(s)
- Benjamin C. Gibson
- Psychology Clinical Neuroscience Center, Department of Psychology, University of New Mexico, Albuquerque, NM, United States
| | - Joseph L. Sanguinetti
- Psychology Clinical Neuroscience Center, Department of Psychology, University of New Mexico, Albuquerque, NM, United States
- U.S. Army Research Laboratory, Aberdeen Proving Ground, MD, United States
| | - Bashar W. Badran
- Psychology Clinical Neuroscience Center, Department of Psychology, University of New Mexico, Albuquerque, NM, United States
- U.S. Army Research Laboratory, Aberdeen Proving Ground, MD, United States
- Department of Biomedical Engineering, The City College of New York, New York, NY, United States
- Brain Stimulation Laboratory, Department of Psychiatry, Medical University of South Carolina, Charleston, SC, United States
| | - Alfred B. Yu
- U.S. Army Research Laboratory, Aberdeen Proving Ground, MD, United States
| | - Evan P. Klein
- Psychology Clinical Neuroscience Center, Department of Psychology, University of New Mexico, Albuquerque, NM, United States
| | - Christopher C. Abbott
- Department of Psychiatry, University of New Mexico School of Medicine, Albuquerque, NM, United States
| | | | - Vincent P. Clark
- Psychology Clinical Neuroscience Center, Department of Psychology, University of New Mexico, Albuquerque, NM, United States
- Department of Neurosciences, University of New Mexico School of Medicine, Albuquerque, NM, United States
- The Mind Research Network & LBERI, Albuquerque, NM, United States
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Dyke K, Kim S, Jackson GM, Jackson SR. Reliability of single and paired pulse transcranial magnetic stimulation parameters across eight testing sessions. Brain Stimul 2018; 11:1393-1394. [DOI: 10.1016/j.brs.2018.08.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 08/16/2018] [Indexed: 10/28/2022] Open
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33
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Testing assumptions on prefrontal transcranial direct current stimulation: Comparison of electrode montages using multimodal fMRI. Brain Stimul 2018; 11:998-1007. [DOI: 10.1016/j.brs.2018.05.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 03/25/2018] [Accepted: 05/01/2018] [Indexed: 11/19/2022] Open
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Bikson M, Brunoni AR, Charvet LE, Clark VP, Cohen LG, Deng ZD, Dmochowski J, Edwards DJ, Frohlich F, Kappenman ES, Lim KO, Loo C, Mantovani A, McMullen DP, Parra LC, Pearson M, Richardson JD, Rumsey JM, Sehatpour P, Sommers D, Unal G, Wassermann EM, Woods AJ, Lisanby SH. Rigor and reproducibility in research with transcranial electrical stimulation: An NIMH-sponsored workshop. Brain Stimul 2018; 11:465-480. [PMID: 29398575 PMCID: PMC5997279 DOI: 10.1016/j.brs.2017.12.008] [Citation(s) in RCA: 119] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 12/01/2017] [Accepted: 12/21/2017] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Neuropsychiatric disorders are a leading source of disability and require novel treatments that target mechanisms of disease. As such disorders are thought to result from aberrant neuronal circuit activity, neuromodulation approaches are of increasing interest given their potential for manipulating circuits directly. Low intensity transcranial electrical stimulation (tES) with direct currents (transcranial direct current stimulation, tDCS) or alternating currents (transcranial alternating current stimulation, tACS) represent novel, safe, well-tolerated, and relatively inexpensive putative treatment modalities. OBJECTIVE This report seeks to promote the science, technology and effective clinical applications of these modalities, identify research challenges, and suggest approaches for addressing these needs in order to achieve rigorous, reproducible findings that can advance clinical treatment. METHODS The National Institute of Mental Health (NIMH) convened a workshop in September 2016 that brought together experts in basic and human neuroscience, electrical stimulation biophysics and devices, and clinical trial methods to examine the physiological mechanisms underlying tDCS/tACS, technologies and technical strategies for optimizing stimulation protocols, and the state of the science with respect to therapeutic applications and trial designs. RESULTS Advances in understanding mechanisms, methodological and technological improvements (e.g., electronics, computational models to facilitate proper dosing), and improved clinical trial designs are poised to advance rigorous, reproducible therapeutic applications of these techniques. A number of challenges were identified and meeting participants made recommendations made to address them. CONCLUSIONS These recommendations align with requirements in NIMH funding opportunity announcements to, among other needs, define dosimetry, demonstrate dose/response relationships, implement rigorous blinded trial designs, employ computational modeling, and demonstrate target engagement when testing stimulation-based interventions for the treatment of mental disorders.
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Affiliation(s)
- Marom Bikson
- Department of Biomedical Engineering, The City College of the City University of New York, United States
| | - Andre R Brunoni
- Laboratory of Neurosciences (LIM-27), Department and Institute of Psychiatry, University of Sao Paulo, Sao Paulo, Brazil
| | - Leigh E Charvet
- Department of Neurology, New York University School of Medicine, New York, NY, United States
| | - Vincent P Clark
- Department of Psychology, University of New Mexico, Albuquerque, NM, United States
| | - Leonardo G Cohen
- Human Cortical Physiology and Neurorehabilitation Section, National Institute of Neurological Disorders and Stroke, Bethesda, MD, United States
| | - Zhi-De Deng
- Experimental Therapeutics and Pathophysiology Branch, National Institute of Mental Health, Bethesda, MD, United States
| | - Jacek Dmochowski
- Department of Biomedical Engineering, The City College of the City University of New York, United States
| | - Dylan J Edwards
- Non-invasive Brain Stimulation and Human Motor Control Laboratory, Burke Rehabilitation and Research, Burke-Cornell Medical Research Facility, White Plains, New York and School of Medicine and Health Sciences, Edith Cowan University, Perth, Australia
| | - Flavio Frohlich
- Department of Psychiatry, Cell Biology and Physiology, Biomedical Engineering, and Neurology, Carolina Center for Neurostimulation, University of North Carolina School of Medicine, Chapel Hill, NC, United States
| | - Emily S Kappenman
- Department of Psychology, San Diego State University, San Diego, CA, United States
| | - Kelvin O Lim
- Department of Psychiatry, University of Minnesota, Minneapolis Veterans Administration Health Care System, and Defense Veterans Brain Injury Center, Minneapolis, MN, United States
| | - Colleen Loo
- School of Psychiatry and Black Dog Institute, University of New South Wales, Sydney, Australia
| | - Antonio Mantovani
- Department of Physiology, Pharmacology and Neuroscience, City College of the City University of New York, New York, NY, United States
| | - David P McMullen
- Division of Translational Research, National Institute of Mental Health, Bethesda, MD, United States
| | - Lucas C Parra
- Department of Biomedical Engineering, The City College of the City University of New York, United States
| | - Michele Pearson
- Division of Translational Research, National Institute of Mental Health, Bethesda, MD, United States
| | - Jessica D Richardson
- Department of Speech and Hearing Sciences, University of New Mexico, Albuquerque, NM, United States
| | - Judith M Rumsey
- Division of Translational Research, National Institute of Mental Health, Bethesda, MD, United States.
| | - Pejman Sehatpour
- Department of Psychiatry, Columbia University, New York, NY, United States
| | - David Sommers
- Scientific Review Branch, National Institute of Mental Health, Bethesda, MD, United States
| | - Gozde Unal
- Department of Biomedical Engineering, The City College of the City University of New York, United States
| | - Eric M Wassermann
- Behavioral Neurology Unit, National Institute of Neurological Disorders and Stroke, Bethesda, MD, United States
| | - Adam J Woods
- Department of Clinical and Health Psychology, Center for Cognitive Aging and Memory, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
| | - Sarah H Lisanby
- Division of Translational Research, National Institute of Mental Health, Bethesda, MD, United States
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Peled-Avron L, Glasner L, Gvirts HZ, Shamay-Tsoory SG. The role of the inferior frontal gyrus in vicarious social touch: A transcranial direct current stimulation (tDCS) study. Dev Cogn Neurosci 2018; 35:115-121. [PMID: 29773509 PMCID: PMC6968961 DOI: 10.1016/j.dcn.2018.04.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 03/29/2018] [Accepted: 04/26/2018] [Indexed: 12/23/2022] Open
Abstract
The neural mechanisms facilitating the experience of vicarious social touch are largely unknown. The right inferior frontal gyrus (rIFG) has been suggested as part of a simulation observation-execution neural network that plays a key role in the perception of tactile stimuli. Considering that vicarious social touch involves vicarious sharing of emotions, we hypothesized that emotional empathy, i.e., the ability to feel what another individual is feeling, modulates the neural responses to vicarious touch. To examine the role of the rIFG in vicarious touch and its modulation by levels of emotional empathy, we used anodal transcranial direct current stimulation (tDCS) on forty participants who observed photos depicting social touch, nonsocial touch or no touch during tDCS or sham stimulation. The results show that while participants with high levels of emotional empathy exhibited no change in ratings of vicarious social touch, participants with low levels of emotional empathy rate human touch as more emotional following anodal stimulation of the rIFG than following sham stimulation. These findings indicate that emotional responses to vicarious social touch are associated with rIFG activity and are modulated by levels of emotional empathy. This result has major therapeutic potential for individuals with low empathic abilities, such as those with ASD.
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Affiliation(s)
| | - Laura Glasner
- Department of Psychology, University of Haifa, Haifa, Israel.
| | - Hila Z Gvirts
- Department of Behavioral Sciences and Psychology, Ariel University, Ariel, Israel.
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36
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Jalali R, Chowdhury A, Wilson M, Miall RC, Galea JM. Neural changes associated with cerebellar tDCS studied using MR spectroscopy. Exp Brain Res 2018; 236:997-1006. [PMID: 29404634 PMCID: PMC5887008 DOI: 10.1007/s00221-018-5170-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 01/05/2018] [Indexed: 12/26/2022]
Abstract
Anodal cerebellar transcranial direct current stimulation (tDCS) is known to enhance motor learning, and therefore, has been suggested to hold promise as a therapeutic intervention. However, the neural mechanisms underpinning the effects of cerebellar tDCS are currently unknown. We investigated the neural changes associated with cerebellar tDCS using magnetic resonance spectroscopy (MRS). 34 healthy participants were divided into two groups which received either concurrent anodal or sham cerebellar tDCS during a visuomotor adaptation task. The anodal group underwent an additional session involving MRS in which the main inhibitory and excitatory neurotransmitters: GABA and glutamate (Glu) were measured pre-, during, and post anodal cerebellar tDCS, but without the behavioural task. We found no significant group-level changes in GABA or glutamate during- or post-tDCS compared to pre-tDCS levels, however, there was large degree of variability across participants. Although cerebellar tDCS did not affect visuomotor adaptation, surprisingly cerebellar tDCS increased motor memory retention with this being strongly correlated with a decrease in cerebellar glutamate levels during tDCS across participants. This work provides novel insights regarding the neural mechanisms which may underlie cerebellar tDCS, but also reveals limitations in the ability to produce robust effects across participants and between studies.
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Affiliation(s)
- Roya Jalali
- Physical Sciences of Imaging in the Biomedical Sciences (PSIBS), University of Birmingham, Birmingham, B15 2TT, UK. .,School of Psychology, University of Birmingham, Birmingham, B15 2TT, UK.
| | - Alimul Chowdhury
- School of Psychology, University of Birmingham, Birmingham, B15 2TT, UK.,Medical Physics, University Hospitals Birmingham NHS Foundation Trust, Birmingham, B15 2TH, UK
| | - Martin Wilson
- School of Psychology, University of Birmingham, Birmingham, B15 2TT, UK
| | - R Chris Miall
- School of Psychology, University of Birmingham, Birmingham, B15 2TT, UK
| | - Joseph M Galea
- School of Psychology, University of Birmingham, Birmingham, B15 2TT, UK
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37
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Sex Mediates the Effects of High-Definition Transcranial Direct Current Stimulation on “Mind-Reading”. Neuroscience 2017; 366:84-94. [DOI: 10.1016/j.neuroscience.2017.10.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 09/23/2017] [Accepted: 10/04/2017] [Indexed: 01/30/2023]
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38
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Using tDCS priming to improve brain function: Can metaplasticity provide the key to boosting outcomes? Neurosci Biobehav Rev 2017; 83:155-159. [DOI: 10.1016/j.neubiorev.2017.09.029] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 09/08/2017] [Accepted: 09/26/2017] [Indexed: 11/23/2022]
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39
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Learmonth G, Felisatti F, Siriwardena N, Checketts M, Benwell CSY, Märker G, Thut G, Harvey M. No Interaction between tDCS Current Strength and Baseline Performance: A Conceptual Replication. Front Neurosci 2017; 11:664. [PMID: 29249932 PMCID: PMC5717015 DOI: 10.3389/fnins.2017.00664] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 11/15/2017] [Indexed: 01/05/2023] Open
Abstract
Several recent studies have reported non-linear effects of transcranial direct current stimulation (tDCS), which has been attributed to an interaction between the stimulation parameters (e.g., current strength, duration) and the neural state of the cortex being stimulated (e.g., indexed by baseline performance ability, age) (see Fertonani and Miniussi, 2016). We have recently described one such non-linear interaction between current strength and baseline performance on a visuospatial attention (landmark) task (Benwell et al., 2015). In this previous study, we induced a small overall rightward shift of spatial attention across 38 participants using bi-hemispheric tDCS applied for 20 min (concurrent left posterior parietal (P5) anode and right posterior parietal (P6) cathode) relative to a sham protocol. Importantly, this shift in bias was driven by a state-dependent interaction between current intensity and the discrimination sensitivity of the participant at baseline (pre-stimulation) for the landmark task. Individuals with high discrimination sensitivity (HDS) shifted rightward in response to low- (1 mA) but not high-intensity (2 mA) tDCS, whereas individuals with low discrimination sensitivity (LDS) shifted rightward with high- but not low-intensity stimulation. However, in Benwell et al. (2015) current strength was applied as a between-groups factor, where half of the participants received 1 mA and half received 2 mA tDCS, thus we were unable to compare high and low-intensity tDCS directly within each individual. Here we aimed to replicate these findings using a within-group design. Thirty young adults received 15 min of 1 and 2 mA tDCS, and a sham protocol, each on different days, to test the concept of an interaction between baseline performance and current strength. We found no overall rightward shift of spatial attention with either current strength, and no interaction between performance and current strength. These results provide further evidence of low replicability of non-invasive brain stimulation protocols, and the need for further attempts to replicate the key experimental findings within this field.
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Affiliation(s)
- Gemma Learmonth
- Centre for Cognitive Neuroimaging, Institute of Neuroscience and Psychology, University of Glasgow, Glasgow, United Kingdom.,School of Psychology, University of Glasgow, Glasgow, United Kingdom
| | | | | | - Matthew Checketts
- School of Psychology, University of Glasgow, Glasgow, United Kingdom
| | - Christopher S Y Benwell
- Centre for Cognitive Neuroimaging, Institute of Neuroscience and Psychology, University of Glasgow, Glasgow, United Kingdom.,School of Psychology, University of Glasgow, Glasgow, United Kingdom
| | - Gesine Märker
- Centre for Cognitive Neuroimaging, Institute of Neuroscience and Psychology, University of Glasgow, Glasgow, United Kingdom.,School of Psychology, University of Glasgow, Glasgow, United Kingdom
| | - Gregor Thut
- Centre for Cognitive Neuroimaging, Institute of Neuroscience and Psychology, University of Glasgow, Glasgow, United Kingdom
| | - Monika Harvey
- School of Psychology, University of Glasgow, Glasgow, United Kingdom
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40
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Thair H, Holloway AL, Newport R, Smith AD. Transcranial Direct Current Stimulation (tDCS): A Beginner's Guide for Design and Implementation. Front Neurosci 2017; 11:641. [PMID: 29213226 PMCID: PMC5702643 DOI: 10.3389/fnins.2017.00641] [Citation(s) in RCA: 243] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 11/06/2017] [Indexed: 12/22/2022] Open
Abstract
Transcranial direct current stimulation (tDCS) is a popular brain stimulation method that is used to modulate cortical excitability, producing facilitatory or inhibitory effects upon a variety of behaviors. There is, however, a current lack of consensus between studies, with many results suggesting that polarity-specific effects are difficult to obtain. This article explores some of these differences and highlights the experimental parameters that may underlie their occurrence. We provide a general, practical snapshot of tDCS methodology, including what it is used for, how to use it, and considerations for designing an effective and safe experiment. Our aim is to equip researchers who are new to tDCS with the essential knowledge so that they can make informed and well-rounded decisions when designing and running successful experiments. By summarizing the varied approaches, stimulation parameters, and outcomes, this article should help inform future tDCS research in a variety of fields.
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Affiliation(s)
- Hayley Thair
- School of Psychology, University of Nottingham, Nottingham, United Kingdom
| | - Amy L Holloway
- School of Psychology, University of Nottingham, Nottingham, United Kingdom
| | - Roger Newport
- School of Psychology, University of Nottingham, Nottingham, United Kingdom
| | - Alastair D Smith
- School of Psychology, University of Nottingham, Nottingham, United Kingdom.,School of Psychology, University of Plymouth, Plymouth, United Kingdom
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41
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Polarity-independent effects of tDCS on paired associative stimulation-induced plasticity. Brain Stimul 2017; 10:1061-1069. [DOI: 10.1016/j.brs.2017.07.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 07/24/2017] [Accepted: 07/25/2017] [Indexed: 12/19/2022] Open
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Shirota Y, Terney D, Antal A, Paulus W. Influence of Concurrent Finger Movements on Transcranial Direct Current Stimulation (tDCS)-Induced Aftereffects. Front Behav Neurosci 2017; 11:169. [PMID: 28955211 PMCID: PMC5600944 DOI: 10.3389/fnbeh.2017.00169] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 08/29/2017] [Indexed: 11/13/2022] Open
Abstract
Transcranial direct current stimulation (tDCS) has been reported to have bidirectional influence on the amplitude of motor-evoked potentials (MEPs) in resting participants in a polarity-specific manner: anodal tDCS increased and cathodal tDCS decreased them. More recently, the effects of tDCS have been shown to depend on a number of additional factors. We investigated whether a small variety of movements involving target and non-target muscles could differentially modify the efficacy of tDCS. MEPs were elicited from the right first dorsal interosseous muscle, defined as the target muscle, by single pulse transcranial magnetic stimulation (TMS) over the primary motor cortex (M1). During M1 tDCS, which lasted for 10 min applying anodal, cathodal, or sham condition, the participants were instructed to squeeze a ball with their right hand (Task 1), to move their right index finger only in the medial (Task 2), in the lateral direction (Task 3), or in medial and lateral direction alternatively (Task 4). Anodal tDCS reduced MEP amplitudes measured in Task 1 and Task 2, but to a lesser extent in the latter. In Task 3, anodal tDCS led to greater MEP amplitudes than cathodal stimulation. Alternating movements resulted in no effect of tDCS on MEP amplitude (Task 4). The results are congruent with the current notion that the aftereffects of tDCS are highly variable relying on a number of factors including the type of movements executed during stimulation.
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Affiliation(s)
- Yuichiro Shirota
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Georg-August UniversityGöttingen, Germany
| | - Daniella Terney
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Georg-August UniversityGöttingen, Germany
| | - Andrea Antal
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Georg-August UniversityGöttingen, Germany
| | - Walter Paulus
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Georg-August UniversityGöttingen, Germany
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43
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Dissanayaka T, Zoghi M, Farrell M, Egan GF, Jaberzadeh S. Does transcranial electrical stimulation enhance corticospinal excitability of the motor cortex in healthy individuals? A systematic review and meta-analysis. Eur J Neurosci 2017; 46:1968-1990. [DOI: 10.1111/ejn.13640] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 07/03/2017] [Accepted: 07/04/2017] [Indexed: 12/12/2022]
Affiliation(s)
- Thusharika Dissanayaka
- Department of Physiotherapy; School of Primary Health Care; Faculty of Medicine; Nursing and Health Sciences; Monash University; Melbourne Victoria Australia
| | - Maryam Zoghi
- Department of Rehabilitation, Nutrition and Sport; School of Allied Health; La Trobe University; Bundoora Victoria Australia
| | - Michael Farrell
- Monash Biomedical Imaging; Monash University; Melbourne Victoria Australia
- Biomedicine Discovery Institute and Department of Medical Imaging and Radiation Sciences; Monash University; Melbourne Victoria Australia
| | - Gary F. Egan
- Monash Biomedical Imaging; Monash University; Melbourne Victoria Australia
| | - Shapour Jaberzadeh
- Department of Physiotherapy; School of Primary Health Care; Faculty of Medicine; Nursing and Health Sciences; Monash University; Melbourne Victoria Australia
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44
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Martin AK, Meinzer M, Lindenberg R, Sieg MM, Nachtigall L, Flöel A. Effects of Transcranial Direct Current Stimulation on Neural Networks in Young and Older Adults. J Cogn Neurosci 2017; 29:1817-1828. [PMID: 28707568 DOI: 10.1162/jocn_a_01166] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Transcranial direct current stimulation (tDCS) may be a viable tool to improve motor and cognitive function in advanced age. However, although a number of studies have demonstrated improved cognitive performance in older adults, other studies have failed to show restorative effects. The neural effects of beneficial stimulation response in both age groups is lacking. In the current study, tDCS was administered during simultaneous fMRI in 42 healthy young and older participants. Semantic word generation and motor speech baseline tasks were used to investigate behavioral and neural effects of uni- and bihemispheric motor cortex tDCS in a three-way, crossover, sham tDCS controlled design. Independent components analysis assessed differences in task-related activity between the two age groups and tDCS effects at the network level. We also explored whether laterality of language network organization was effected by tDCS. Behaviorally, both active tDCS conditions significantly improved semantic word retrieval performance in young and older adults and were comparable between groups and stimulation conditions. Network-level tDCS effects were identified in the ventral and dorsal anterior cingulate networks in the combined sample during semantic fluency and motor speech tasks. In addition, a shift toward enhanced left laterality was identified in the older adults for both active stimulation conditions. Thus, tDCS results in common network-level modulations and behavioral improvements for both age groups, with an additional effect of increasing left laterality in older adults.
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Affiliation(s)
| | | | | | - Mira M Sieg
- Charité University Medicine, Berlin, Germany
| | | | - Agnes Flöel
- Charité University Medicine, Berlin, Germany.,University of Greifswald
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45
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Wörsching J, Padberg F, Helbich K, Hasan A, Koch L, Goerigk S, Stoecklein S, Ertl-Wagner B, Keeser D. Test-retest reliability of prefrontal transcranial Direct Current Stimulation (tDCS) effects on functional MRI connectivity in healthy subjects. Neuroimage 2017; 155:187-201. [PMID: 28450138 DOI: 10.1016/j.neuroimage.2017.04.052] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 04/22/2017] [Indexed: 01/01/2023] Open
Abstract
Transcranial Direct Current Stimulation (tDCS) of the prefrontal cortex (PFC) can be used for probing functional brain connectivity and meets general interest as novel therapeutic intervention in psychiatric and neurological disorders. Along with a more extensive use, it is important to understand the interplay between neural systems and stimulation protocols requiring basic methodological work. Here, we examined the test-retest (TRT) characteristics of tDCS-induced modulations in resting-state functional-connectivity MRI (RS fcMRI). Twenty healthy subjects received 20minutes of either active or sham tDCS of the dorsolateral PFC (2mA, anode over F3 and cathode over F4, international 10-20 system), preceded and ensued by a RS fcMRI (10minutes each). All subject underwent three tDCS sessions with one-week intervals in between. Effects of tDCS on RS fcMRI were determined at an individual as well as at a group level using both ROI-based and independent-component analyses (ICA). To evaluate the TRT reliability of individual active-tDCS and sham effects on RS fcMRI, voxel-wise intra-class correlation coefficients (ICC) of post-tDCS maps between testing sessions were calculated. For both approaches, results revealed low reliability of RS fcMRI after active tDCS (ICC(2,1) = -0.09 - 0.16). Reliability of RS fcMRI (baselines only) was low to moderate for ROI-derived (ICC(2,1) = 0.13 - 0.50) and low for ICA-derived connectivity (ICC(2,1) = 0.19 - 0.34). Thus, for ROI-based analyses, the distribution of voxel-wise ICC was shifted to lower TRT reliability after active, but not after sham tDCS, for which the distribution was similar to baseline. The intra-individual variation observed here resembles variability of tDCS effects in motor regions and may be one reason why in this study robust tDCS effects at a group level were missing. The data can be used for appropriately designing large scale studies investigating methodological issues such as sources of variability and localisation of tDCS effects.
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Affiliation(s)
- Jana Wörsching
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Germany.
| | - Frank Padberg
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Germany
| | - Konstantin Helbich
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Germany
| | - Alkomiet Hasan
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Germany
| | - Lena Koch
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Germany
| | - Stephan Goerigk
- Department of Psychological Methodology and Assessment, Ludwig-Maximilians-University, Munich, Germany
| | - Sophia Stoecklein
- Institute for Clinical Radiology, Ludwig-Maximilians-University, Munich, Germany
| | - Birgit Ertl-Wagner
- Institute for Clinical Radiology, Ludwig-Maximilians-University, Munich, Germany
| | - Daniel Keeser
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Germany; Institute for Clinical Radiology, Ludwig-Maximilians-University, Munich, Germany
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46
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Response variability of different anodal transcranial direct current stimulation intensities across multiple sessions. Brain Stimul 2017; 10:757-763. [PMID: 28420581 DOI: 10.1016/j.brs.2017.04.003] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 02/01/2017] [Accepted: 04/07/2017] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND It is well known that transcranial direct current stimulation (tDCS) is capable of modulating corticomotor excitability. However, a source of growing concern has been the observed inter- and intra-individual variability of tDCS-responses. Recent studies have assessed whether individuals respond in a predictable manner across repeated sessions of anodal tDCS (atDCS). The findings of these investigations have been inconsistent, and their methods have some limitations (i.e. lack of sham condition or testing only one tDCS intensity). OBJECTIVE To study inter- and intra-individual variability of atDCS effects at two different intensities on primary motor cortex (M1) excitability. METHODS Twelve subjects participated in a crossover study testing 7-min atDCS over M1 in three separate conditions (2 mA, 1 mA, sham) each repeated three times separated by 48 h. Motor evoked potentials were recorded before and after stimulation (up to 30min). Time of testing was maintained consistent within participants. To estimate the reliability of tDCS effects across sessions, we calculated the Intra-class Correlation Coefficient (ICC). RESULTS AtDCS at 2 mA, but not 1 mA, significantly increased cortical excitability at the group level in all sessions. The overall ICC revealed fair to high reliability of tDCS effects for multiple sessions. Given that the distribution of responses showed important variability in the sham condition, we established a Sham Variability-Based Threshold to classify responses and to track individual changes across sessions. Using this threshold an intra-individual consistent response pattern was then observed only for the 2 mA condition. CONCLUSION 2 mA anodal tDCS results in consistent intra- and inter-individual increases of M1 excitability.
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47
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Reteig LC, Talsma LJ, van Schouwenburg MR, Slagter HA. Transcranial Electrical Stimulation as a Tool to Enhance Attention. JOURNAL OF COGNITIVE ENHANCEMENT 2017. [DOI: 10.1007/s41465-017-0010-y] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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48
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Spampinato D, Celnik P. Temporal dynamics of cerebellar and motor cortex physiological processes during motor skill learning. Sci Rep 2017; 7:40715. [PMID: 28091578 PMCID: PMC5238434 DOI: 10.1038/srep40715] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 12/08/2016] [Indexed: 11/30/2022] Open
Abstract
Learning motor tasks involves distinct physiological processes in the cerebellum (CB) and primary motor cortex (M1). Previous studies have shown that motor learning results in at least two important neurophysiological changes: modulation of cerebellar output mediated in-part by long-term depression of parallel fiber-Purkinje cell synapse and induction of long-term plasticity (LTP) in M1, leading to transient occlusion of additional LTP-like plasticity. However, little is known about the temporal dynamics of these two physiological mechanisms during motor skill learning. Here we use non-invasive brain stimulation to explore CB and M1 mechanisms during early and late motor skill learning in humans. We predicted that early skill acquisition would be proportional to cerebellar excitability (CBI) changes, whereas later stages of learning will result in M1 LTP-like plasticity modifications. We found that early, and not late into skill training, CBI changed. Whereas, occlusion of LTP-like plasticity over M1 occurred only during late, but not early training. These findings indicate a distinct temporal dissociation in the physiological role of the CB and M1 when learning a novel skill. Understanding the role and temporal dynamics of different brain regions during motor learning is critical to device optimal interventions to augment learning.
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Affiliation(s)
- D Spampinato
- Department of Biomedical Engineering, Johns Hopkins School of Medicine, 720 Rutland Avenue Baltimore, MD 21205, USA.,Department of Physical Medicine and Rehabilitation, Johns Hopkins School of Medicine, 600 North Wolfe Street Baltimore, MD 21287, USA
| | - P Celnik
- Department of Physical Medicine and Rehabilitation, Johns Hopkins School of Medicine, 600 North Wolfe Street Baltimore, MD 21287, USA.,Department of Neuroscience, Johns Hopkins School of Medicine, 725 North Wolfe Street Baltimore, MD 21205, USA.,Department of Neurology, Johns Hopkins School of Medicine, 600 North Wolfe Street Baltimore, MD 21287, USA
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