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Shen B, Xiao S, Yu C, Zhang C, Zhan J, Liu Y, Fu W. Cerebral hemodynamics underlying ankle force sense modulated by high-definition transcranial direct current stimulation. Cereb Cortex 2024; 34:bhae226. [PMID: 38850217 DOI: 10.1093/cercor/bhae226] [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: 04/08/2024] [Revised: 05/07/2024] [Accepted: 05/14/2024] [Indexed: 06/10/2024] Open
Abstract
This study aimed to investigate the effects of high-definition transcranial direct current stimulation on ankle force sense and underlying cerebral hemodynamics. Sixteen healthy adults (8 males and 8 females) were recruited in the study. Each participant received either real or sham high-definition transcranial direct current stimulation interventions in a randomly assigned order on 2 visits. An isokinetic dynamometer was used to assess the force sense of the dominant ankle; while the functional near-infrared spectroscopy was employed to monitor the hemodynamics of the sensorimotor cortex. Two-way analyses of variance with repeated measures and Pearson correlation analyses were performed. The results showed that the absolute error and root mean square error of ankle force sense dropped more after real stimulation than after sham stimulation (dropped by 23.4% vs. 14.9% for absolute error, and 20.0% vs. 10.2% for root mean square error). The supplementary motor area activation significantly increased after real high-definition transcranial direct current stimulation. The decrease in interhemispheric functional connectivity within the Brodmann's areas 6 was significantly correlated with ankle force sense improvement after real high-definition transcranial direct current stimulation. In conclusion, high-definition transcranial direct current stimulation can be used as a potential intervention for improving ankle force sense. Changes in cerebral hemodynamics could be one of the explanations for the energetic effect of high-definition transcranial direct current stimulation.
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Affiliation(s)
- Bin Shen
- School of Exercise and Health, Shanghai University of Sport, 200 Hengren Road, Yangpu District, Shanghai 200438, China
| | - Songlin Xiao
- School of Exercise and Health, Shanghai University of Sport, 200 Hengren Road, Yangpu District, Shanghai 200438, China
| | - Changxiao Yu
- School of Exercise and Health, Shanghai University of Sport, 200 Hengren Road, Yangpu District, Shanghai 200438, China
| | - Chuyi Zhang
- School of Exercise and Health, Shanghai University of Sport, 200 Hengren Road, Yangpu District, Shanghai 200438, China
| | - Jianglong Zhan
- School of Exercise and Health, Shanghai University of Sport, 200 Hengren Road, Yangpu District, Shanghai 200438, China
| | - Ying Liu
- School of Psychology, Shanghai University of Sport, 399 Changhai Road, Yangpu District, Shanghai 200438, China
| | - Weijie Fu
- School of Exercise and Health, Shanghai University of Sport, 200 Hengren Road, Yangpu District, Shanghai 200438, China
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, 200 Hengren Road, Yangpu District, Shanghai 200438, China
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Dai J, Xiao Y, Chen G, Gu Z, Xu K. Anodal transcranial direct current stimulation enhances response inhibition and attention allocation in fencers. PeerJ 2024; 12:e17288. [PMID: 38699193 PMCID: PMC11064870 DOI: 10.7717/peerj.17288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 04/02/2024] [Indexed: 05/05/2024] Open
Abstract
Background The aim of this study is to investigate the acute effects of anodal transcranial direct current stimulation (tDCS) on reaction time, response inhibition and attention in fencers. Methods Sixteen professional female fencers were recruited, and subjected to anodal tDCS and sham stimulation in the primary motor area (M1) one week apart in a randomized, crossover, single-blind design. A two-factor analysis of variance with repeated measures was used to analyze the effects of stimulation conditions (anodal stimulation, sham stimulation) and time (pre-stimulation, post-stimulation) on reaction time, response inhibition, and attention in fencers. Results The study found a significant improvement in response inhibition and attention allocation from pre-stimulation to post-stimulation following anodal tDCS but not after sham stimulation. There was no statistically significant improvement in reaction time and selective attention. Conclusions A single session of anodal tDCS could improve response inhibition, attention allocation in female fencers. This shows that tDCS has potential to improve aspects of an athlete's cognitive performance, although we do not know if such improvements would transfer to improved performance in competition. However, more studies involving all genders, large samples, and different sports groups are needed in the future to further validate the effect of tDCS in improving the cognitive performance of athletes.
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Affiliation(s)
- Jiansong Dai
- Department of Sport and Health Sciences, Nanjing Sport Institute, Nanjing, China
| | - Yang Xiao
- Department of Graduate, Nanjing Sport Institute, Nanjing, China
| | - Gangrui Chen
- Department of Sport Research, Nanjing Sport Institute, Nanjing, China
| | - Zhongke Gu
- Department of Sport and Health Sciences, Nanjing Sport Institute, Nanjing, China
| | - Kai Xu
- Department of Sport and Health Sciences, Nanjing Sport Institute, Nanjing, China
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Muller CO, Metais A, Boublay N, Breuil C, Deligault S, Di Rienzo F, Guillot A, Collet C, Krolak-Salmon P, Saimpont A. Anodal transcranial direct current stimulation does not enhance the effects of motor imagery training of a sequential finger-tapping task in young adults. J Sports Sci 2024:1-12. [PMID: 38574326 DOI: 10.1080/02640414.2024.2328418] [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: 06/05/2023] [Accepted: 03/01/2024] [Indexed: 04/06/2024]
Abstract
When applied over the primary motor cortex (M1), anodal transcranial direct current stimulation (a-tDCS) could enhance the effects of a single motor imagery training (MIt) session on the learning of a sequential finger-tapping task (SFTT). This study aimed to investigate the effect of a-tDCS on the learning of an SFTT during multiple MIt sessions. Two groups of 16 healthy young adults participated in three consecutive MIt sessions over 3 days, followed by a retention test 1 week later. They received active or sham a-tDCS during a MIt session in which they mentally rehearsed an eight-item complex finger sequence with their left hand. Before and after each session, and during the retention test, they physically repeated the sequence as quickly and accurately as possible. Both groups (i) improved their performance during the first two sessions, showing online learning; (ii) stabilised the level they reached during all training sessions, reflecting offline consolidation; and (iii) maintained their performance level one week later, showing retention. However, no significant difference was found between the groups, regardless of the MSL stage. These results emphasise the importance of performing several MIt sessions to maximise performance gains, but they do not support the additional effects of a-tDCS.
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Affiliation(s)
- Camille O Muller
- Universite Claude Bernard Lyon 1, LIBM, Inter-university Laboratory of Human Movement Sciences, UR 7424, F-69622 Villeurbanne, France
- EuroMov Digital Health in Motion, Univ Montpellier, IMT Mines Alès, Montpellier, France
| | - Angèle Metais
- Universite Claude Bernard Lyon 1, LIBM, Inter-university Laboratory of Human Movement Sciences, UR 7424, F-69622 Villeurbanne, France
| | - Nawale Boublay
- Centre de Recherche Clinique Vieillissement Cerveau - Fragilité, Hospices Civils de Lyon, Lyon, France
| | - Caroline Breuil
- Universite Claude Bernard Lyon 1, LIBM, Inter-university Laboratory of Human Movement Sciences, UR 7424, F-69622 Villeurbanne, France
| | - Sébastien Deligault
- Centre d'Etude et de Recherche Multimodal et Pluridisciplinaire en Imagerie du Vivant (CERMEP), Département de MagnétoEncéphalographie, Bron, France
| | - Franck Di Rienzo
- Universite Claude Bernard Lyon 1, LIBM, Inter-university Laboratory of Human Movement Sciences, UR 7424, F-69622 Villeurbanne, France
| | - Aymeric Guillot
- Universite Claude Bernard Lyon 1, LIBM, Inter-university Laboratory of Human Movement Sciences, UR 7424, F-69622 Villeurbanne, France
| | - Christian Collet
- Universite Claude Bernard Lyon 1, LIBM, Inter-university Laboratory of Human Movement Sciences, UR 7424, F-69622 Villeurbanne, France
| | - Pierre Krolak-Salmon
- Centre de Recherche Clinique Vieillissement Cerveau - Fragilité, Hospices Civils de Lyon, Lyon, France
| | - Arnaud Saimpont
- Universite Claude Bernard Lyon 1, LIBM, Inter-university Laboratory of Human Movement Sciences, UR 7424, F-69622 Villeurbanne, France
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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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Straudi S, Antonioni A, Baroni A, Bonsangue V, Lavezzi S, Koch G, Tisato V, Ziliotto N, Basaglia N, Secchiero P, Manfredini F, Lamberti N. Anti-Inflammatory and Cortical Responses after Transcranial Direct Current Stimulation in Disorders of Consciousness: An Exploratory Study. J Clin Med 2023; 13:108. [PMID: 38202115 PMCID: PMC10779892 DOI: 10.3390/jcm13010108] [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: 10/31/2023] [Revised: 12/06/2023] [Accepted: 12/22/2023] [Indexed: 01/12/2024] Open
Abstract
Disorders of consciousness (DoC) due to severe traumatic brain injury (TBI) are associated with severe disability and an alteration of cortical activation, angiogenesis, and inflammation, which are crucial elements for behavioural recovery. This exploratory study aimed to evaluate anti-inflammatory and cortical responses after transcranial direct current stimulation (tDCS) in traumatic prolonged disorders of consciousness. Ten minimally conscious state (MCS) patients underwent ten sessions of anodal tDCS (five sessions/week, two weeks, 40 min/session) on the primary motor cortex bilaterally. Clinical evaluations were performed using the Coma Recovery Scale-Revised (CRS-R) pre- and post-treatment. In contrast, after single and multiple tDCS sessions, the haemodynamic cortical response was obtained with functional near-infrared spectroscopy (fNIRS). Moreover, angiogenesis (angiopoietin-2, BMP9, endoglin, HbEFG, HGF, IL8, Leptin, PLGF, VEGF-A, and VEGF-C) and inflammation (GM-CSF, IFNg, IP10, MCP1, and TNFα) circulating biomarkers were collected. A significant haemodynamic response was observed after a single tDCS session, with an increased activation from 4.4 (3.1-6.1) to 7.6 (2.9-15.7) a.u. (p = 0.035). After ten tDCS sessions, a significant reduction of angiopoietin-2, VEGF-C, and IP-10 was detected. Moreover, a correlation between behavioural (CRS-R), TNFα (r = 0.89; p = 0.007), and IP10 (r = 0.81; p = 0.014) variation was found. In conclusion, a single tDCS session can increase the cortical activation in MCS patients. Moreover, multiple tDCS sessions showed an anti-inflammatory effect related to behavioural improvement.
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Affiliation(s)
- Sofia Straudi
- Department of Neuroscience and Rehabilitation, Ferrara University, 44121 Ferrara, Italy; (S.S.); (A.A.); (A.B.); (G.K.); (N.B.)
- Department of Neuroscience, Ferrara University Hospital, 44124 Ferrara, Italy; (V.B.); (S.L.)
| | - Annibale Antonioni
- Department of Neuroscience and Rehabilitation, Ferrara University, 44121 Ferrara, Italy; (S.S.); (A.A.); (A.B.); (G.K.); (N.B.)
- Doctoral Program in Translational Neurosciences and Neurotechnologies, Ferrara University, 44121 Ferrara, Italy
| | - Andrea Baroni
- Department of Neuroscience and Rehabilitation, Ferrara University, 44121 Ferrara, Italy; (S.S.); (A.A.); (A.B.); (G.K.); (N.B.)
- Department of Neuroscience, Ferrara University Hospital, 44124 Ferrara, Italy; (V.B.); (S.L.)
| | - Valentina Bonsangue
- Department of Neuroscience, Ferrara University Hospital, 44124 Ferrara, Italy; (V.B.); (S.L.)
| | - Susanna Lavezzi
- Department of Neuroscience, Ferrara University Hospital, 44124 Ferrara, Italy; (V.B.); (S.L.)
| | - Giacomo Koch
- Department of Neuroscience and Rehabilitation, Ferrara University, 44121 Ferrara, Italy; (S.S.); (A.A.); (A.B.); (G.K.); (N.B.)
| | - Veronica Tisato
- Department of Translational Medicine, Ferrara University, 44121 Ferrara, Italy
| | - Nicole Ziliotto
- Department of Pharmacy, University of Pisa, 56126 Pisa, Italy;
| | - Nino Basaglia
- Department of Neuroscience and Rehabilitation, Ferrara University, 44121 Ferrara, Italy; (S.S.); (A.A.); (A.B.); (G.K.); (N.B.)
- Department of Neuroscience, Ferrara University Hospital, 44124 Ferrara, Italy; (V.B.); (S.L.)
| | - Paola Secchiero
- Department of Translational Medicine, Ferrara University, 44121 Ferrara, Italy
| | - Fabio Manfredini
- Department of Neuroscience and Rehabilitation, Ferrara University, 44121 Ferrara, Italy; (S.S.); (A.A.); (A.B.); (G.K.); (N.B.)
- Department of Neuroscience, Ferrara University Hospital, 44124 Ferrara, Italy; (V.B.); (S.L.)
| | - Nicola Lamberti
- Department of Neuroscience and Rehabilitation, Ferrara University, 44121 Ferrara, Italy; (S.S.); (A.A.); (A.B.); (G.K.); (N.B.)
- Department of Neuroscience, Ferrara University Hospital, 44124 Ferrara, Italy; (V.B.); (S.L.)
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6
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Simpson MW, Mak M. Modulating Cortical Hemodynamic Activity in Parkinson's Disease Using Focal Transcranial Direct Current Stimulation: A Pilot Functional Near-infrared Spectroscopy Study. Brain Topogr 2023; 36:926-935. [PMID: 37676389 DOI: 10.1007/s10548-023-01002-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 08/14/2023] [Indexed: 09/08/2023]
Abstract
Reduced thalamocortical facilitation of the motor cortex in PD leads to characteristic motor deficits such as bradykinesia. Recent research has highlighted improved motor function following tDCS, but a lack of neurophysiological evidence limits the progress of tDCS as an adjunctive therapy. Here, we tested the hypothesis that tDCS may modulate M1 hemodynamic activity in PD and healthy using functional near-infrared spectroscopy (fNIRS). In this randomized crossover experiment, fourteen PD and twelve healthy control participants attended three laboratory sessions and performed a regulated (3 Hz) right index finger tapping task before and after receiving tDCS. On each visit, participants received either anodal, cathodal, or sham tDCS applied over M1. Hemodynamic activity of M1 was quantified using fNIRS. Significant task related activity was observed in M1 and the inferior parietal lobe in PD and healthy (p < 0.05). PD additionally recruited the dorsal premotor cortex. During tDCS, while at rest, anodal and cathodal tDCS significantly increased the oxygenated hemoglobin concentration of M1 compared to sham (t62 = 4.09 and t62 = 4.25, respectively). Task related hemodynamic activity was unchanged following any tDCS intervention (p > 0.05). Task related hemodynamic activity of M1 is not modulated by tDCS in PD or healthy. During tDCS, both anodal and cathodal stimulation cause a significant increase of M1 oxygenation, the clinical significance of which remains to be clarified.
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Affiliation(s)
- Michael W Simpson
- Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China
| | - Margaret Mak
- Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China.
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7
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Muller CO, Perrey S, Bakhti K, Muthalib M, Dray G, Xu B, Mottet D, Laffont I. Aging effects on electrical and hemodynamic responses in the sensorimotor network during unilateral proximal upper limb functional tasks. Behav Brain Res 2023; 443:114322. [PMID: 36731658 DOI: 10.1016/j.bbr.2023.114322] [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: 10/10/2022] [Revised: 01/04/2023] [Accepted: 01/29/2023] [Indexed: 02/01/2023]
Abstract
Healthy aging leads to poorer performance in upper limb (UL) daily living movements. Understanding the neural correlates linked with UL functional movements may help to better understand how healthy aging affects motor control. Two non-invasive neuroimaging methods allow for monitoring the movement-related brain activity: functional near-infrared spectroscopy (fNIRS) and electroencephalography (EEG), respectively based on the hemodynamic response and electrical activity of brain regions. Coupled, they provide a better spatiotemporal mapping. The aim of this study was to evaluate the effect of healthy aging on the bilateral sensorimotor (SM1) activation patterns of functional proximal UL movements. Twenty-one young and 21 old healthy participants realized two unilateral proximal UL movements during: i) a paced reaching target task and ii) a circular steering task to capture the speed-accuracy trade-off. Combined fNIRS-EEG system was synchronised with movement capture system to record SM1 activation while moving. The circular steering task performance was significantly lower for the older group. The rate of increase in hemodynamic response was longer in the older group with no difference on the amplitude of fNIRS signal for the two tasks. The EEG results showed aging related reduction of the alpha-beta rhythms synchronisation but no desynchronisation modification. In conclusion, this study uncovers the age-related changes in brain electrical and hemodynamic response patterns in the bilateral sensorimotor network during two functional proximal UL movements using two complementary neuroimaging methods. This opens up the possibility to utilise combined fNIRS-EEG for monitoring the movement-related neuroplasticity in clinical practice.
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Affiliation(s)
- C O Muller
- EuroMov Digital Health in Motion, Univ Montpellier, IMT Mines Ales, Montpellier, France; Physical Rehabilitation and Medicine, CHU Montpellier, Montpellier, France.
| | - S Perrey
- EuroMov Digital Health in Motion, Univ Montpellier, IMT Mines Ales, Montpellier, France
| | - K Bakhti
- EuroMov Digital Health in Motion, Univ Montpellier, IMT Mines Ales, Montpellier, France; Physical Rehabilitation and Medicine, CHU Montpellier, Montpellier, France; Clinical Research and Epidemiology unit, CHU Montpellier, Univ Montpellier, Montpellier, France
| | - M Muthalib
- EuroMov Digital Health in Motion, Univ Montpellier, IMT Mines Ales, Montpellier, France; Physical Rehabilitation and Medicine, CHU Montpellier, Montpellier, France; Silverline Research, Brisbane, Australia
| | - G Dray
- EuroMov Digital Health in Motion, Univ Montpellier, IMT Mines Ales, Montpellier, France
| | - B Xu
- EuroMov Digital Health in Motion, Univ Montpellier, IMT Mines Ales, Montpellier, France
| | - D Mottet
- EuroMov Digital Health in Motion, Univ Montpellier, IMT Mines Ales, Montpellier, France
| | - I Laffont
- EuroMov Digital Health in Motion, Univ Montpellier, IMT Mines Ales, Montpellier, France; Physical Rehabilitation and Medicine, CHU Montpellier, Montpellier, France
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8
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Gellner AK, Frase S, Reis J, Fritsch B. Direct current stimulation increases blood flow and permeability of cortical microvasculature in vivo. Eur J Neurol 2023; 30:362-371. [PMID: 36305221 DOI: 10.1111/ene.15616] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 10/08/2022] [Accepted: 10/12/2022] [Indexed: 01/07/2023]
Abstract
BACKGROUND AND PURPOSE Transcranial direct current stimulation (DCS) structurally and functionally modulates neuronal networks and microglia dynamics. Neurovascular coupling adapts regional cerebral blood flow to neuronal activity and metabolic demands. METHODS In this study, we examined effects of anodal DCS on vessel morphology, blood flow parameters, permeability of cortical microvasculature, and perivascular microglia motility by time-lapse two-photon microscopy in anaesthetized mice. RESULTS Low-intensity DCS significantly increased vessel diameter and blood flow parameters. These effects were transient and dependent on the spontaneous vasomotion characteristics of the individual vessel. Vessel leakage increased significantly after DCS at 1.1 and was more pronounced at 2.2 A/m2 , indicating a dose-dependent increase in vascular permeability. Perivascular microglia exhibited increased soma motility post-DCS at both intensities, potentially triggered by the extravasation of intravascular substrates. CONCLUSIONS Our findings demonstrate that DCS affected only vessels with spontaneous vasomotion. This rapid vascular response may occur as an adaptation of regional blood supply to neuronal excitability altered by DCS or as a direct effect on the vessel wall. In contrast to these immediate effects during stimulation, increases in cortical vessel permeability and perivascular microglia motility appeared after the stimulation had ended.
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Affiliation(s)
- Anne-Kathrin Gellner
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany
- Department of Neurology and Neuroscience, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Sibylle Frase
- Department of Neurology and Neuroscience, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Janine Reis
- Department of Neurology and Neuroscience, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Brita Fritsch
- Department of Neurology and Neuroscience, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
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9
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Amaral L, Donato R, Valério D, Caparelli-Dáquer E, Almeida J, Bergström F. Disentangling hand and tool processing: Distal effects of neuromodulation. Cortex 2022; 157:142-154. [PMID: 36283136 DOI: 10.1016/j.cortex.2022.08.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 05/29/2022] [Accepted: 08/24/2022] [Indexed: 12/15/2022]
Abstract
Neural processing within a local brain region that responds to more than one object category (e.g., hands and tools) nonetheless have different functional connectivity patterns with other distal brain areas, which suggests that local processing can affect and/or be affected by processing in distal areas, in a category-specific way. Here we wanted to test whether administering either a hand- or tool-related training task in tandem with transcranial direct current stimulation (tDCS) to a region that responds both to hands and tools (posterior middle temporal gyrus; pMTG), modulated local and distal neural processing more for the trained than the untrained category in a subsequent fMRI task. After each combined tDCS/training session, participants viewed images of tools, hands, and animals, in an fMRI scanner. Using multivoxel pattern analysis, we found that tDCS stimulation to pMTG indeed improved the classification accuracy between tools vs. animals, but only when combined with a tool and not a hand training task. Surprisingly, tDCS stimulation to pMTG also improved classification accuracy between hands vs. animals when combined with a tool but not a hand training task. Our findings suggest that overlapping but functionally-specific networks may be engaged separately by using a category-specific training task together with tDCS - a strategy that can be applied more broadly to other cognitive domains using tDCS. By hypothesis, these effects on local processing are a direct result of within-domain connectivity constraints from domain-specific networks that are at play in the processing and organization of object representations.
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Affiliation(s)
- Lénia Amaral
- Proaction Laboratory, Faculty of Psychology and Educational Sciences, University of Coimbra. Portugal; CINEICC, Faculty of Psychology and Educational Sciences, University of Coimbra. Portugal
| | - Rita Donato
- Proaction Laboratory, Faculty of Psychology and Educational Sciences, University of Coimbra. Portugal; Department of General Psychology, University of Padova, Italy; Human Inspired Technology Centre, University of Padova, Italy
| | - Daniela Valério
- Proaction Laboratory, Faculty of Psychology and Educational Sciences, University of Coimbra. Portugal; CINEICC, Faculty of Psychology and Educational Sciences, University of Coimbra. Portugal
| | - Egas Caparelli-Dáquer
- Laboratory of Electrical Stimulation of the Nervous System (LabEEL), Rio de Janeiro State University, Brazil
| | - Jorge Almeida
- Proaction Laboratory, Faculty of Psychology and Educational Sciences, University of Coimbra. Portugal; CINEICC, Faculty of Psychology and Educational Sciences, University of Coimbra. Portugal.
| | - Fredrik Bergström
- Proaction Laboratory, Faculty of Psychology and Educational Sciences, University of Coimbra. Portugal; CINEICC, Faculty of Psychology and Educational Sciences, University of Coimbra. Portugal; Department of Psychology, University of Gothenburg, Sweden.
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10
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Hong KS, Khan MNA, Ghafoor U. Non-invasive transcranial electrical brain stimulation guided by functional near-infrared spectroscopy for targeted neuromodulation: A review. J Neural Eng 2022; 19. [PMID: 35905708 DOI: 10.1088/1741-2552/ac857d] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 07/29/2022] [Indexed: 11/12/2022]
Abstract
One of the primary goals in cognitive neuroscience is to understand the neural mechanisms on which cognition is based. Researchers are trying to find how cognitive mechanisms are related to oscillations generated due to brain activity. The research focused on this topic has been considerably aided by developing non-invasive brain stimulation techniques. The dynamics of brain networks and the resultant behavior can be affected by non-invasive brain stimulation techniques, which make their use a focus of interest in many experiments and clinical fields. One essential non-invasive brain stimulation technique is transcranial electrical stimulation (tES), subdivided into transcranial direct and alternating current stimulation. tES has recently become more well-known because of the effective results achieved in treating chronic conditions. In addition, there has been exceptional progress in the interpretation and feasibility of tES techniques. Summarizing the beneficial effects of tES, this article provides an updated depiction of what has been accomplished to date, brief history, and the open questions that need to be addressed in the future. An essential issue in the field of tES is stimulation duration. This review briefly covers the stimulation durations that have been utilized in the field while monitoring the brain using functional-near infrared spectroscopy-based brain imaging.
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Affiliation(s)
- Keum-Shik Hong
- Department of Cogno-mechatronics Engineering, Pusan National University, 2 Busandaehak-ro, Geumgeong-gu, Busan, Busan, 609735, Korea (the Republic of)
| | - M N Afzal Khan
- Pusan National University, Department of Mechanical Engineering, Busan, 46241, Korea (the Republic of)
| | - Usman Ghafoor
- School of Mechanical Engineering, Pusan National University College of Engineering, room 204, Busan, 46241, Korea (the Republic of)
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Stefano LHS, Favoretto DB, Nascimento DC, Santos LRA, Louzada F, Bikson M, Leite JP, Pontes-Neto OM, Edwards DJ, Edwards TGS. Middle cerebral artery blood flow stability in response to high-definition transcranial electrical stimulation: a randomized sham-controlled clinical trial. Clin Neurol Neurosurg 2022; 220:107345. [DOI: 10.1016/j.clineuro.2022.107345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 06/11/2022] [Accepted: 06/16/2022] [Indexed: 11/28/2022]
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12
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Modulation of Interhemispheric Synchronization and Cortical Activity in Healthy Subjects by High-Definition Theta-Burst Electrical Stimulation. Neural Plast 2022; 2022:3593262. [PMID: 35529454 PMCID: PMC9076342 DOI: 10.1155/2022/3593262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 04/18/2022] [Indexed: 11/24/2022] Open
Abstract
Background Various forms of theta-burst stimulation (TBS) such as intermittent TBS (iTBS) and continuous TBS (cTBS) have been introduced as novel facilitation/suppression schemes during repetitive transcranial magnetic stimulation (rTMS), demonstrating a better efficacy than conventional paradigms. Herein, we extended the rTMS-TBS schemes to electrical stimulation of high-definition montage (HD-TBS) and investigated its neural effects on the human brain. Methods In a within-subject design, fifteen right-handed healthy adults randomly participated in 10 min and 2 mA HD-TBS sessions: unilateral (Uni)-iTBS, bilateral (Bi)-cTBS/iTBS, and sham stimulation over primary motor cortex regions. A 20-channel near-infrared spectroscopy (NIRS) system was covered on the bilateral prefrontal cortex (PFC), sensory motor cortex (SMC), and parietal lobe (PL) for observing cerebral hemodynamic responses in the resting-state and during fast finger-tapping tasks at pre-, during, and poststimulation. Interhemispheric correlation coefficient (IHCC) and wavelet phase coherence (WPCO) from resting-state NIRS and concentration of oxyhemoglobin during fast finger-tapping tasks were explored to reflect the symmetry between the two hemispheres and cortical activity, respectively. Results The IHCC and WPCO of NIRS data in the SMC region under Bi-cTBS/iTBS showed relatively small values at low-frequency bands III (0.06–0.15 Hz) and IV (0.02–0.06), indicating a significant desynchronization in both time and frequency domains. In addition, the SMC activation induced by fast finger-tapping exercise was significantly greater during Uni-iTBS as well as during and post Bi-cTBS/iTBS sessions. Conclusions It appears that a 10 min and 2 mA Bi-cTBS/iTBS applied over two hemispheres within the primary motor cortex region could effectively modulate the interhemispheric synchronization and cortical activation in the SMC of healthy subjects. Our study demonstrated that bilateral HD-TBS approaches is an effective noninvasive brain stimulation scheme which could be a novel therapeutic for inducing effects of neuromodulation on various neurological disorders caused by ischemic stroke or traumatic brain injuries.
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Chenot Q, Hamery C, Lepron E, Besson P, De Boissezon X, Perrey S, Scannella S. Performance after training in a complex cognitive task is enhanced by high-definition transcranial random noise stimulation. Sci Rep 2022; 12:4618. [PMID: 35301388 PMCID: PMC8931133 DOI: 10.1038/s41598-022-08545-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 02/28/2022] [Indexed: 11/10/2022] Open
Abstract
Interest for neuromodulation, and transcranial random noise stimulation (tRNS) in particular, is growing. It concerns patients rehabilitation, but also healthy people who want or need to improve their cognitive and learning abilities. However, there is no consensus yet regarding the efficacy of tRNS on learning and performing a complex task. In particular, the most effective electrode montage is yet to be determined. Here, we examined the effect of two different tRNS montages on learning rate, short- and long-term performance in a video game (Space Fortress) that engages multiple cognitive abilities. Sixty-one participants were randomly assigned to one of three groups (sham vs. simple-definition tRNS vs. high-definition tRNS) in a double-blind protocol. Their performance on the Space Fortress task was monitored during a 15-day experiment with baseline (day 1), stimulation (day 2 to 4), short- (day 5) and long-term (day 15) evaluations. Our results show that the high-definition tRNS group improved more on the long term than simple-definition tRNS group, tended to learn faster and had better performance retention compared to both simple-definition tRNS and sham groups. This study is the first to report that high-definition tRNS is more effective than conventional simple-definition tRNS to enhance performance in a complex task.
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Affiliation(s)
| | | | | | - Pierre Besson
- EuroMov Digital Health in Motion, Univ Montpellier, IMT Mines Ales, Montpellier, France
| | - Xavier De Boissezon
- Toulouse Neuroimaging Center (ToNIC), Université de Toulouse, INSERM, Toulouse, France.,Department of Physical Medicine and Rehabilitation, University Hospital of Toulouse, Toulouse, France
| | - Stéphane Perrey
- EuroMov Digital Health in Motion, Univ Montpellier, IMT Mines Ales, Montpellier, France
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14
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Hu K, Chen Y, Guo F, Wang X. Effects of Transcranial Direct Current Stimulation on Upper Limb Muscle Strength and Endurance in Healthy Individuals: A Systematic Review and Meta-Analysis. Front Physiol 2022; 13:834397. [PMID: 35356085 PMCID: PMC8959826 DOI: 10.3389/fphys.2022.834397] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Accepted: 02/03/2022] [Indexed: 01/28/2023] Open
Abstract
Objective Whether transcranial direct current stimulation (tDCS) can improve upper limb muscle strength and endurance in healthy subjects is still controversial. This article reviews the relevant literature on the use of tDCS to improve upper limb muscle strength and endurance in healthy individuals. Methods We systematically searched the Cochrane Library, PubMed, EMBASE, and the Web of Science until September 4, 2021. Randomized parallel or crossover experimental studies on the effects of tDCS on upper limb muscle strength and endurance in healthy individuals were included. Review Manager 5.3 software was used to evaluate methodological quality and analyze the combined effect of the included literature. Results Twelve studies (189 participants) were included in the qualitative synthesis, and nine studies (146 participants) were included in the meta-analysis. Compared with the control group, the tDCS intervention had no significant effect on improving upper limb muscle strength [I2 = 0%, 95% CI (−0.79, 0.23), p = 0.98, MD = 0.01]. In this analysis, tDCS had a significant heterogeneity (I2 = 87%) in improving upper limb muscle endurance compared with the control group. After the subgroup analysis and the sensitivity analysis, the source of heterogeneity was excluded. The final results showed that tDCS had a significant effect on improving upper limb muscle endurance [I2 = 0%, 95% CI (1.91, 4.83), p < 0.00001, MD = 3.37]. Conclusions tDCS has no significant effect on improvement of upper limb muscle strength, but has a significant effect on improving upper limb endurance performance (especially on the non-dominant side).
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Ghafoor U, Yang D, Hong KS. Neuromodulatory effects of HD-tACS/tDCS on the prefrontal cortex: A resting-state fNIRS-EEG study. IEEE J Biomed Health Inform 2021; 26:2192-2203. [PMID: 34757916 DOI: 10.1109/jbhi.2021.3127080] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Transcranial direct and alternating current stimulation (tDCS and tACS, respectively) can modulate human brain dynamics and cognition. However, these modalities have not been compared using multiple imaging techniques concurrently. In this study, 15 participants participated in an experiment involving two sessions with a gap of 10 d. In the first and second sessions, tACS and tDCS were administered to the participants. The anode for tDCS was positioned at point FpZ, and four cathodes were positioned over the left and right prefrontal cortices (PFCs) to target the frontal regions simultaneously. tDCS was administered with 1 mA current. tACS was supplied with a current of 1 mA (zero-to-peak value) at 10 Hz frequency. Stimulation was applied concomitantly with functional near-infrared spectroscopy and electroencephalography acquisitions in the resting-state. The statistical test showed significant alteration (p < 0.001) in the mean hemodynamic responses during and after tDCS and tACS periods. Between-group comparison revealed a significantly less (p < 0.001) change in the mean hemodynamic response caused by tACS compared with tDCS. As hypothesized, we successfully increased the hemodynamics in both left and right PFCs using tDCS and tACS. Moreover, a significant increase in alpha-band power (p < 0.01) and low beta band power (p < 0.05) due to tACS was observed after the stimulation period. Although tDCS is not frequency-specific, it increased but not significantly (p > 0.05) the powers of most bands including delta, theta, alpha, low beta, high beta, and gamma. These findings suggest that both hemispheres can be targeted and that both tACS and tDCS are equally effective in high-definition configurations, which may be of clinical relevance.
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16
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Muller CO, Muthalib M, Mottet D, Perrey S, Dray G, Delorme M, Duflos C, Froger J, Xu B, Faity G, Pla S, Jean P, Laffont I, Bakhti KKA. Recovering arm function in chronic stroke patients using combined anodal HD-tDCS and virtual reality therapy (ReArm): a study protocol for a randomized controlled trial. Trials 2021; 22:747. [PMID: 34702317 PMCID: PMC8549202 DOI: 10.1186/s13063-021-05689-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 10/05/2021] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND After a stroke, 80% of the chronic patients have difficulties to use their paretic upper limb (UL) in activities of daily life (ADL) even after rehabilitation. Virtual reality therapy (VRT) and anodal transcranial direct current stimulation (tDCS) are two innovative methods that have shown independently to positively impact functional recovery of the paretic UL when combined with conventional therapy. The objective of the project will be to evaluate the impact of adding anodal high-definition (HD)-tDCS during an intensive 3-week UL VRT and conventional therapy program on paretic UL function in chronic stroke. METHODS The ReArm project is a quadruple-blinded, randomized, sham-controlled, bi-centre, two-arm parallel, and interventional study design. Fifty-eight chronic (> 3 months) stroke patients will be recruited from the Montpellier and Nimes University Hospitals. Patients will follow a standard 3-week in-patient rehabilitation program, which includes 13 days of VRT (Armeo Spring, 1 × 30 min session/day) and conventional therapy (3 × 30 min sessions/day). Twenty-nine patients will receive real stimulation (4x1 anodal HD-tDCS montage, 2 mA, 20 min) to the ipsilesional primary motor cortex during the VRT session and the other 29 patients will receive active sham stimulation (2 mA, 30 s). All outcome measures will be assessed at baseline, at the end of rehabilitation and again 3 months later. The primary outcome measure will be the wolf motor function test. Secondary outcomes will include measures of UL function (Box and Block Test), impairment (Fugl Meyer Upper Extremity), compensation (Proximal Arm Non-Use), ADL (Actimetry, Barthel Index). Other/exploratory outcomes will include pain, fatigue, effort and performance, kinematics, and motor cortical region activation during functional motor tasks. DISCUSSION This will be the first trial to determine the impact of adding HD-tDCS during UL VRT and conventional therapy in chronic stroke patients. We hypothesize that improvements in UL function will be greater and longer-lasting with real stimulation than in those receiving sham. TRIAL REGISTRATION The ReArm project was approved by The French Research Ethics Committee, (Comité de Protection des Personnes-CPP SUD-EST II, N°ID-RCB: 2019-A00506-51, http://www.cppsudest2.fr/ ). The ReArm project was registered on ClinicalTrials.gov ( NCT04291573 , 2nd March 2020.
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Affiliation(s)
- Camille O Muller
- Physical and Rehabilitation Medicine, Centre Hospitalier Universitaire (CHU) - Montpellier, Lapeyronie, 371 Avenue du Doyen Gaston Giraud, 34295, Montpellier, Cédex 15, France
- EuroMov Digital Health in Motion, Université Montpellier, IMT Mines Alès, Montpellier, France
| | - Makii Muthalib
- Physical and Rehabilitation Medicine, Centre Hospitalier Universitaire (CHU) - Montpellier, Lapeyronie, 371 Avenue du Doyen Gaston Giraud, 34295, Montpellier, Cédex 15, France
- EuroMov Digital Health in Motion, Université Montpellier, IMT Mines Alès, Montpellier, France
- Silverline Research, Brisbane, Australia
| | - Denis Mottet
- EuroMov Digital Health in Motion, Université Montpellier, IMT Mines Alès, Montpellier, France
| | - Stéphane Perrey
- EuroMov Digital Health in Motion, Université Montpellier, IMT Mines Alès, Montpellier, France
| | - Gérard Dray
- EuroMov Digital Health in Motion, Université Montpellier, IMT Mines Alès, Montpellier, France
| | - Marion Delorme
- EuroMov Digital Health in Motion, Université Montpellier, IMT Mines Alès, Montpellier, France
- Physical and Rehabilitation Medicine, CHU Nîmes, Le Grau du Roi, France
| | - Claire Duflos
- Clinical Research and Epidemiology unit, CHU Montpellier, Université Montpellier, Montpellier, France
| | - Jérôme Froger
- EuroMov Digital Health in Motion, Université Montpellier, IMT Mines Alès, Montpellier, France
- Physical and Rehabilitation Medicine, CHU Nîmes, Le Grau du Roi, France
| | - Binbin Xu
- EuroMov Digital Health in Motion, Université Montpellier, IMT Mines Alès, Montpellier, France
| | - Germain Faity
- EuroMov Digital Health in Motion, Université Montpellier, IMT Mines Alès, Montpellier, France
| | - Simon Pla
- EuroMov Digital Health in Motion, Université Montpellier, IMT Mines Alès, Montpellier, France
| | - Pierre Jean
- EuroMov Digital Health in Motion, Université Montpellier, IMT Mines Alès, Montpellier, France
| | - Isabelle Laffont
- Physical and Rehabilitation Medicine, Centre Hospitalier Universitaire (CHU) - Montpellier, Lapeyronie, 371 Avenue du Doyen Gaston Giraud, 34295, Montpellier, Cédex 15, France
- EuroMov Digital Health in Motion, Université Montpellier, IMT Mines Alès, Montpellier, France
| | - Karima K A Bakhti
- Physical and Rehabilitation Medicine, Centre Hospitalier Universitaire (CHU) - Montpellier, Lapeyronie, 371 Avenue du Doyen Gaston Giraud, 34295, Montpellier, Cédex 15, France.
- EuroMov Digital Health in Motion, Université Montpellier, IMT Mines Alès, Montpellier, France.
- Health Directorate, CHU Montpellier, Montpellier, France.
- Clinical Investigation Centre, CHU Montpellier, Montpellier, France - Inserm, CIC 1411, Montpellier, France.
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Grey-box modeling and hypothesis testing of functional near-infrared spectroscopy-based cerebrovascular reactivity to anodal high-definition tDCS in healthy humans. PLoS Comput Biol 2021; 17:e1009386. [PMID: 34613970 PMCID: PMC8494321 DOI: 10.1371/journal.pcbi.1009386] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 08/28/2021] [Indexed: 12/12/2022] Open
Abstract
Transcranial direct current stimulation (tDCS) has been shown to evoke hemodynamics response; however, the mechanisms have not been investigated systematically using systems biology approaches. Our study presents a grey-box linear model that was developed from a physiologically detailed multi-compartmental neurovascular unit model consisting of the vascular smooth muscle, perivascular space, synaptic space, and astrocyte glial cell. Then, model linearization was performed on the physiologically detailed nonlinear model to find appropriate complexity (Akaike information criterion) to fit functional near-infrared spectroscopy (fNIRS) based measure of blood volume changes, called cerebrovascular reactivity (CVR), to high-definition (HD) tDCS. The grey-box linear model was applied on the fNIRS-based CVR during the first 150 seconds of anodal HD-tDCS in eleven healthy humans. The grey-box linear models for each of the four nested pathways starting from tDCS scalp current density that perturbed synaptic potassium released from active neurons for Pathway 1, astrocytic transmembrane current for Pathway 2, perivascular potassium concentration for Pathway 3, and voltage-gated ion channel current on the smooth muscle cell for Pathway 4 were fitted to the total hemoglobin concentration (tHb) changes from optodes in the vicinity of 4x1 HD-tDCS electrodes as well as on the contralateral sensorimotor cortex. We found that the tDCS perturbation Pathway 3 presented the least mean square error (MSE, median <2.5%) and the lowest Akaike information criterion (AIC, median -1.726) from the individual grey-box linear model fitting at the targeted-region. Then, minimal realization transfer function with reduced-order approximations of the grey-box model pathways was fitted to the ensemble average tHb time series. Again, Pathway 3 with nine poles and two zeros (all free parameters), provided the best Goodness of Fit of 0.0078 for Chi-Square difference test of nested pathways. Therefore, our study provided a systems biology approach to investigate the initial transient hemodynamic response to tDCS based on fNIRS tHb data. Future studies need to investigate the steady-state responses, including steady-state oscillations found to be driven by calcium dynamics, where transcranial alternating current stimulation may provide frequency-dependent physiological entrainment for system identification. We postulate that such a mechanistic understanding from system identification of the hemodynamics response to transcranial electrical stimulation can facilitate adequate delivery of the current density to the neurovascular tissue under simultaneous portable imaging in various cerebrovascular diseases.
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Yaqub MA, Hong KS, Zafar A, Kim CS. Control of Transcranial Direct Current Stimulation Duration by Assessing Functional Connectivity of Near-Infrared Spectroscopy Signals. Int J Neural Syst 2021; 32:2150050. [PMID: 34609264 DOI: 10.1142/s0129065721500507] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Transcranial direct current stimulation (tDCS) has been shown to create neuroplasticity in healthy and diseased populations. The control of stimulation duration by providing real-time brain state feedback using neuroimaging is a topic of great interest. This study presents the feasibility of a closed-loop modulation for the targeted functional network in the prefrontal cortex. We hypothesize that we cannot improve the brain state further after reaching a specific state during a stimulation therapy session. A high-definition tDCS of 1[Formula: see text]mA arranged in a ring configuration was applied at the targeted right prefrontal cortex of 15 healthy male subjects for 10[Formula: see text]min. Functional near-infrared spectroscopy was used to monitor hemoglobin chromophores during the stimulation period continuously. The correlation matrices obtained from filtered oxyhemoglobin were binarized to form subnetworks of short- and long-range connections. The connectivity in all subnetworks was analyzed individually using a new quantification measure of connectivity percentage based on the correlation matrix. The short-range network in the stimulated hemisphere showed increased connectivity in the initial stimulation phase. However, the increase in connection density reduced significantly after 6[Formula: see text]min of stimulation. The short-range network of the left hemisphere and the long-range network gradually increased throughout the stimulation period. The connectivity percentage measure showed a similar response with network theory parameters. The connectivity percentage and network theory metrics represent the brain state during the stimulation therapy. The results from the network theory metrics, including degree centrality, efficiency, and connection density, support our hypothesis and provide a guideline for feedback on the brain state. The proposed neuro-feedback scheme is feasible to control the stimulation duration to avoid overdosage.
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Affiliation(s)
- M Atif Yaqub
- ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels (Barcelona), Spain
| | - Keum-Shik Hong
- School of Mechanical Engineering, Pusan National University, 2 Busandaehak-ro, Geumjeong-gu, Busan 46241, Korea
| | - Amad Zafar
- Department of Electrical Engineering, University of Lahore, Sihala Zone V, Islamabad, Pakistan
| | - Chang-Seok Kim
- Department of Cogno-Mechatronics Engineering, Pusan National University, 2 Busandaehak-ro, Geumjeong-gu, Busan 46241, Korea
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García-Barajas G, Serrano-Muñoz D, Gómez-Soriano Pt J, Avendaño-Coy J, Fernández-Carnero J, García AM, Segura-Fragosa A, Taylor J. Efficacy of anodal suboccipital direct current stimulation for endogenous pain modulation and tonic thermal pain control in healthy participants: a randomised controlled clinical trial. PAIN MEDICINE 2021; 22:2908-2917. [PMID: 33822227 DOI: 10.1093/pm/pnab125] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE The aim of this study was to assess whether anodal DCS applied to the suboccipital (SO) target area could potentiate antinociception assessed primarily with conditioned pain modulation of tonic thermal test stimuli. DESIGN Randomised double-blinded control trial. SETTING Rehabilitation hospital. SUBJECTS Healthy participants. METHODS Forty healthy participants were randomized to receive either SO-DCS or M1-DCS. The 20-minute 1.5mA anodal or sham DCS intervention were applied to each participant in randomised order during two test sessions. The primary outcome measure included heterotopic cold-pressor conditioned pain modulation (CPM) of tonic heat pain. Secondary measures included pressure pain threshold and tonic thermal pain intensity. RESULTS Heterotopic CPM of tonic heat pain intensity was unaffected by either SO-DCS or active M1, including the secondary measures of pressure pain threshold and tonic thermal pain intensity. Although low-power non-significant interactions were identified for DCS intervention (active versus sham) and time (before and after), a significant within-group inhibition of tonic cold pain was identified following SO-DCS (p = 0.011, mean [SD]: -0.76±0.88 points) and M1-DCS (p < 0.002: -0.84±0.82 points), without a significant change following sham DCS. CONCLUSIONS Although heterotopic CPM was not facilitated with either SO-DCS or M1-DCS, a general significant inhibition of tonic cold pain intensity was demonstrated following both interventions. The general effects of active DCS compared to sham on tonic cold pain-irrespective of the M1 or SO target-need to be confirmed using standard quantitative sensory testing.
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Affiliation(s)
- Guillermo García-Barajas
- Sensorimotor Function Group, Hospital Nacional de Parapléjicos, SESCAM, Toledo, Spain.,Escuela Internacional de Doctorado, Department of Physical Therapy, Occupational Therapy, Rehabilitation and Physical Medicine, Rey Juan Carlos University, Alcorcón, Spain
| | - Diego Serrano-Muñoz
- Toledo Physiotherapy Research Group (GIFTO), Faculty of Physiotherapy and Nursing, Universidad Castilla La Mancha, Toledo, Spain
| | - Julio Gómez-Soriano Pt
- Toledo Physiotherapy Research Group (GIFTO), Faculty of Physiotherapy and Nursing, Universidad Castilla La Mancha, Toledo, Spain
| | - Juan Avendaño-Coy
- Toledo Physiotherapy Research Group (GIFTO), Faculty of Physiotherapy and Nursing, Universidad Castilla La Mancha, Toledo, Spain
| | - Josue Fernández-Carnero
- Department of Physical Therapy, Occupational Therapy, Rehabilitation and Physical Medicine, Universidad Rey Juan Carlos, Madrid, Spain.,La Paz Hospital Institute for Health Research, IdiPAZ, Madrid, Spain.,Grupo Multidisciplinar de Investigación y Tratamiento del Dolor, Grupo de Excelencia Investigadora, Universidad Rey Juan Carlos-Banco de Santander, Madrid, Spain
| | - Alvaro Megía García
- Biomechanical and Technical Aids Unit, Hospital Nacional de Parapléjicos, SESCAM, Toledo, Spain
| | | | - Julian Taylor
- Sensorimotor Function Group, Hospital Nacional de Parapléjicos, SESCAM, Toledo, Spain.,Harris Manchester College, University of Oxford, Oxford, United Kingdom
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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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Schommartz I, Dix A, Passow S, Li SC. Functional Effects of Bilateral Dorsolateral Prefrontal Cortex Modulation During Sequential Decision-Making: A Functional Near-Infrared Spectroscopy Study With Offline Transcranial Direct Current Stimulation. Front Hum Neurosci 2021; 14:605190. [PMID: 33613203 PMCID: PMC7886709 DOI: 10.3389/fnhum.2020.605190] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 12/21/2020] [Indexed: 11/13/2022] Open
Abstract
The ability to learn sequential contingencies of actions for predicting future outcomes is indispensable for flexible behavior in many daily decision-making contexts. It remains open whether such ability may be enhanced by transcranial direct current stimulation (tDCS). The present study combined tDCS with functional near-infrared spectroscopy (fNIRS) to investigate potential tDCS-induced effects on sequential decision-making and the neural mechanisms underlying such modulations. Offline tDCS and sham stimulation were applied over the left and right dorsolateral prefrontal cortex (dlPFC) in young male adults (N = 29, mean age = 23.4 years, SD = 3.2) in a double-blind between-subject design using a three-state Markov decision task. The results showed (i) an enhanced dlPFC hemodynamic response during the acquisition of sequential state transitions that is consistent with the findings from a previous functional magnetic resonance imaging (fMRI) study; (ii) a tDCS-induced increase of the hemodynamic response in the dlPFC, but without accompanying performance-enhancing effects at the behavioral level; and (iii) a greater tDCS-induced upregulation of hemodynamic responses in the delayed reward condition that seems to be associated with faster decision speed. Taken together, these findings provide empirical evidence for fNIRS as a suitable method for investigating hemodynamic correlates of sequential decision-making as well as functional brain correlates underlying tDCS-induced modulation. Future research with larger sample sizes for carrying out subgroup analysis is necessary in order to decipher interindividual differences in tDCS-induced effects on sequential decision-making process at the behavioral and brain levels.
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Affiliation(s)
- Iryna Schommartz
- Chair of Lifespan Developmental Neuroscience, Faculty of Psychology, Technische Universität Dresden, Dresden, Germany
- Department of Developmental Psychology, Institute of Psychology, Goethe University Frankfurt, Frankfurt, Germany
| | - Annika Dix
- Chair of Lifespan Developmental Neuroscience, Faculty of Psychology, Technische Universität Dresden, Dresden, Germany
- Centre for Tactile Internet With Human-in-the-Loop, Technische Universität Dresden, Dresden, Germany
| | - Susanne Passow
- Chair of Lifespan Developmental Neuroscience, Faculty of Psychology, Technische Universität Dresden, Dresden, Germany
| | - Shu-Chen Li
- Chair of Lifespan Developmental Neuroscience, Faculty of Psychology, Technische Universität Dresden, Dresden, Germany
- Centre for Tactile Internet With Human-in-the-Loop, Technische Universität Dresden, Dresden, Germany
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22
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Boonzaier J, Straathof M, Ardesch DJ, van der Toorn A, van Vliet G, van Heijningen CL, Otte WM, Dijkhuizen RM. Activation response and functional connectivity change in rat cortex after bilateral transcranial direct current stimulation-An exploratory study. J Neurosci Res 2021; 99:1377-1389. [PMID: 33511664 PMCID: PMC8048424 DOI: 10.1002/jnr.24793] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 12/14/2020] [Accepted: 01/11/2021] [Indexed: 12/13/2022]
Abstract
Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique implicated as a promising adjunct therapy to improve motor function through the neuromodulation of brain networks. Particularly bilateral tDCS, which affects both hemispheres, may yield stronger effects on motor learning than unilateral stimulation. Therefore, the aim of this exploratory study was to develop an experimental model for simultaneous magnetic resonance imaging (MRI) and bilateral tDCS in rats, to measure instant and resultant effects of tDCS on network activity and connectivity. Naïve, male Sprague‐Dawley rats were divided into a tDCS (n = 7) and sham stimulation group (n = 6). Functional MRI data were collected during concurrent bilateral tDCS over the sensorimotor cortex, while resting‐state functional MRI and perfusion MRI were acquired directly before and after stimulation. Bilateral tDCS induced a hemodynamic activation response, reflected by a bilateral increase in blood oxygenation level‐dependent signal in different cortical areas, including the sensorimotor regions. Resting‐state functional connectivity within the cortical sensorimotor network decreased after a first stimulation session but increased after a second session, suggesting an interaction between multiple tDCS sessions. Perfusion MRI revealed no significant changes in cerebral blood flow after tDCS. Our exploratory study demonstrates successful application of an MRI‐compatible bilateral tDCS setup in an animal model. Our results indicate that bilateral tDCS can locally modulate neuronal activity and connectivity, which may underlie its therapeutic potential.
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Affiliation(s)
- Julia Boonzaier
- Biomedical Magnetic Resonance Imaging and Spectroscopy Group, Center for Image Sciences, University Medical Center Utrecht and Utrecht University, Utrecht, The Netherlands
| | - Milou Straathof
- Biomedical Magnetic Resonance Imaging and Spectroscopy Group, Center for Image Sciences, University Medical Center Utrecht and Utrecht University, Utrecht, The Netherlands
| | - Dirk Jan Ardesch
- Connectome Lab, Department of Complex Trait Genetics, Center for Neurogenomics and Cognitive Research, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Annette van der Toorn
- Biomedical Magnetic Resonance Imaging and Spectroscopy Group, Center for Image Sciences, University Medical Center Utrecht and Utrecht University, Utrecht, The Netherlands
| | - Gerard van Vliet
- Biomedical Magnetic Resonance Imaging and Spectroscopy Group, Center for Image Sciences, University Medical Center Utrecht and Utrecht University, Utrecht, The Netherlands
| | - Caroline L van Heijningen
- Biomedical Magnetic Resonance Imaging and Spectroscopy Group, Center for Image Sciences, University Medical Center Utrecht and Utrecht University, Utrecht, The Netherlands
| | - Willem M Otte
- Biomedical Magnetic Resonance Imaging and Spectroscopy Group, Center for Image Sciences, University Medical Center Utrecht and Utrecht University, Utrecht, The Netherlands.,Department of Pediatric Neurology, UMC Utrecht Brain Center, University Medical Center Utrecht and Utrecht University, Utrecht, The Netherlands
| | - Rick M Dijkhuizen
- Biomedical Magnetic Resonance Imaging and Spectroscopy Group, Center for Image Sciences, University Medical Center Utrecht and Utrecht University, Utrecht, The Netherlands
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23
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Besson P, Muthalib M, De Vassoigne C, Rothwell J, Perrey S. Effects of Multiple Sessions of Cathodal Priming and Anodal HD-tDCS on Visuo Motor Task Plateau Learning and Retention. Brain Sci 2020; 10:E875. [PMID: 33228236 PMCID: PMC7699517 DOI: 10.3390/brainsci10110875] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 10/24/2020] [Accepted: 11/18/2020] [Indexed: 01/18/2023] Open
Abstract
A single session of priming cathodal transcranial direct current stimulation (tDCS) prior to anodal tDCS (c-a-tDCS) allows cumulative effects on motor learning and retention. However, the impact of multiple sessions of c-a-tDCS priming on learning and retention remains unclear. Here, we tested whether multiple sessions of c-a-tDCS (over 3 consecutive days) applied over the left sensorimotor cortex can further enhance motor learning and retention of an already learned visuo-motor task as compared to anodal tDCS (a-tDCS) or sham. In a between group and randomized double-blind sham-controlled study design, 25 participants separated in 3 independent groups underwent 2 days of baseline training without tDCS followed by 3-days of training with both online and offline tDCS, and two retention tests (1 and 14 days later). Each training block consisted of five trials of a 60 s circular-tracing task intersected by 60 s rest, and performance was assessed in terms of speed-accuracy trade-off represented notably by an index of performance (IP). The main findings of this exploratory study were that multiple sessions of c-a-tDCS significantly further enhanced IP above baseline training levels over the 3 training days that were maintained over the 2 retention days, but these learning and retention performance changes were not significantly different from the sham group. Subtle differences in the changes in speed-accuracy trade-off (components of IP) between c-a-tDCS (maintenance of accuracy over increasing speed) and a-tDCS (increasing speed over maintenance of accuracy) provide preliminary insights to a mechanistic modulation of motor performance with priming and polarity of tDCS.
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Affiliation(s)
- Pierre Besson
- EuroMov Digital Health in Motion, Univ Montpellier, IMT Mines Ales, 34090 Montpellier, France; (P.B.); (M.M.); (C.D.V.)
| | - Makii Muthalib
- EuroMov Digital Health in Motion, Univ Montpellier, IMT Mines Ales, 34090 Montpellier, France; (P.B.); (M.M.); (C.D.V.)
- SilverLine Research, 4127 Brisbane, Australia
| | - Christophe De Vassoigne
- EuroMov Digital Health in Motion, Univ Montpellier, IMT Mines Ales, 34090 Montpellier, France; (P.B.); (M.M.); (C.D.V.)
| | - Jonh Rothwell
- Institute of Neurology, University College London, London WC1N 3BG, UK;
| | - Stephane Perrey
- EuroMov Digital Health in Motion, Univ Montpellier, IMT Mines Ales, 34090 Montpellier, France; (P.B.); (M.M.); (C.D.V.)
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24
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Turner DA, Degan S, Galeffi F, Schmidt S, Peterchev AV. Rapid, Dose-Dependent Enhancement of Cerebral Blood Flow by transcranial AC Stimulation in Mouse. Brain Stimul 2020; 14:80-87. [PMID: 33217607 DOI: 10.1016/j.brs.2020.11.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 10/18/2020] [Accepted: 11/12/2020] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Transcranial electrical stimulation at an appropriate dose may demonstrate intracranial effects, including neuronal stimulation and cerebral blood flow responses. OBJECTIVE We performed in vivo experiments on mouse cortex using transcranial alternating current [AC] stimulation to assess whether cerebral blood flow can be reliably altered by extracranial stimulation. METHODS We performed transcranial AC electrical stimulation transversely across the closed skull in anesthetized mice, measuring transcranial cerebral blood flow with a laser Doppler probe and intracranial electrical responses as endpoint biomarkers. We calculated a stimulation dose-response function between intracranial electric field and cerebral blood flow. RESULTS Stimulation at electric field amplitudes of 5-20 mV/mm at 10-20 Hz rapidly increased cerebral blood flow (within 100 ms), which then quickly decreased with no residual effects. The time to peak and blood flow shape varied with stimulation intensity and duration, showing a linear correlation between stimulation dose and peak blood flow increase. Neither afterdischarges nor spreading depression occurred from this level of stimulation. CONCLUSIONS Extracranial stimulation amplitudes sufficient to evoke reliable blood flow changes require electric field strengths higher than what is tolerable in unanesthetized humans (<1 mV/mm), but less than electroconvulsive therapy levels (>40 mV/mm). However, anesthesia effects, spontaneous blood flow fluctuations, and sampling error may accentuate the apparent field strength needed for enhanced blood flow. The translation to a human dose-response function to augment cerebral blood flow (i.e., in stroke recovery) will require significant modification, potentially to pericranial, focused, multi-electrode application or intracranial stimulation.
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Affiliation(s)
- Dennis A Turner
- Neurosurgery, Duke University, USA; Neurobiology, Duke University, USA; Biomedical Engineering, Duke University, USA; Surgery and Research Branches, Durham VAMC, Durham, NC, 27710, USA.
| | - Simone Degan
- Neurosurgery, Duke University, USA; Surgery and Research Branches, Durham VAMC, Durham, NC, 27710, USA
| | - Francesca Galeffi
- Neurosurgery, Duke University, USA; Surgery and Research Branches, Durham VAMC, Durham, NC, 27710, USA
| | - Stephen Schmidt
- Neurosurgery, Duke University, USA; Biomedical Engineering, Duke University, USA
| | - Angel V Peterchev
- Neurosurgery, Duke University, USA; Psychiatry & Behavioral Sciences, Duke University, USA; Biomedical Engineering, Duke University, USA; Electrical & Computer Engineering, Duke University, USA
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25
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Machado L. Understanding cognition and how it changes with aging, brain disease, and lifestyle choices. J R Soc N Z 2020. [DOI: 10.1080/03036758.2020.1796102] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Liana Machado
- Department of Psychology and Brain Health Research Centre, University of Otago, Dunedin, New Zealand
- Brain Research New Zealand, Auckland, New Zealand
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26
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Patel R, Dawidziuk A, Darzi A, Singh H, Leff DR. Systematic review of combined functional near-infrared spectroscopy and transcranial direct-current stimulation studies. NEUROPHOTONICS 2020; 7:020901. [PMID: 32607389 PMCID: PMC7315225 DOI: 10.1117/1.nph.7.2.020901] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 06/15/2020] [Indexed: 05/05/2023]
Abstract
Significance: Combining transcranial direct-current stimulation (tDCS) with functional near-infrared spectroscopy (fNIRS) is a recent approach to exploring brain activation evoked by neurostimulation. Aim: To critically evaluate studies combining tDCS and fNIRS and provide a consolidated overview of cortical hemodynamic responses to neurostimulation. Approach: Key terms were searched in three databases (MEDLINE, EMBASE, and PsycINFO) with cross-referencing and works from Google Scholar also evaluated. All studies reporting on fNIRS-derived hemoglobin changes evoked by tDCS were included. Results: Literature searches revealed 474 articles, of which 28 were included for final review (22 in healthy individuals: 9 involving rest and 13 with tasks; 6 in the clinical setting). At rest, an overall increase in cortical activation was observed in fNIRS responses at the site of stimulation, with evidence suggesting nonstimulated brain regions are also similarly affected. Conversely, during tasks, reduced cortical activation was observed during online stimulation. Offline and poststimulation effects were less consistent, as is the impact on clinical populations and their symptom correlation. Conclusion: This review explores the methodological frameworks for fNIRS-tDCS evaluations and summarizes hemodynamic responses associated with tDCS in all populations. Our findings provide further evidence of the impact of tDCS on neuronal activation within functionally connected networks.
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Affiliation(s)
- Ronak Patel
- St. Mary’s Hospital Campus, Imperial College London, Department of Surgery and Cancer, London, United Kingdom
- Address all correspondence to Ronak Patel, E-mail:
| | - Aleksander Dawidziuk
- St. Mary’s Hospital Campus, Imperial College London, Department of Surgery and Cancer, London, United Kingdom
| | - Ara Darzi
- St. Mary’s Hospital Campus, Imperial College London, Department of Surgery and Cancer, London, United Kingdom
| | - Harsimrat Singh
- St. Mary’s Hospital Campus, Imperial College London, Department of Surgery and Cancer, London, United Kingdom
| | - Daniel Richard Leff
- St. Mary’s Hospital Campus, Imperial College London, Department of Surgery and Cancer, London, United Kingdom
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27
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Jones KT, Johnson EL, Berryhill ME. Frontoparietal theta-gamma interactions track working memory enhancement with training and tDCS. Neuroimage 2020; 211:116615. [PMID: 32044440 PMCID: PMC7733399 DOI: 10.1016/j.neuroimage.2020.116615] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Revised: 01/14/2020] [Accepted: 02/05/2020] [Indexed: 01/17/2023] Open
Abstract
Despite considerable interest in enhancing, preserving, and rehabilitating working memory (WM), efforts to elicit sustained behavioral improvements have been met with limited success. Here, we paired WM training with transcranial direct current stimulation (tDCS) to the frontoparietal network over four days. Active tDCS enhanced WM performance by modulating interactions between frontoparietal theta oscillations and gamma activity, as measured by pre- and post-training high-density electroencephalography (EEG). Increased phase-amplitude coupling (PAC) between the prefrontal stimulation site and temporo-parietal gamma activity explained behavioral improvements, and was most effective when gamma occurred near the prefrontal theta peak. These results demonstrate for the first time that tDCS-linked WM training elicits lasting changes in behavior by optimizing the oscillatory substrates of prefrontal control.
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Affiliation(s)
- Kevin T Jones
- University of Nevada-Reno, Department of Psychology, Cognitive and Brain Sciences, Reno, NV, 89557, USA; University of California-San Francisco, Department of Neurology, Neuroscape, San Francisco, CA, 94158, USA
| | - Elizabeth L Johnson
- University of California-Berkeley, Helen Wills Neuroscience Institute, Berkeley, CA, 94720, USA; Wayne State University, Institute of Gerontology, Life-Span Cognitive Neuroscience Program, Detroit, MI, 48202, USA
| | - Marian E Berryhill
- University of Nevada-Reno, Department of Psychology, Cognitive and Brain Sciences, Reno, NV, 89557, USA.
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28
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Jamil A, Batsikadze G, Kuo HI, Meesen RLJ, Dechent P, Paulus W, Nitsche MA. Current intensity- and polarity-specific online and aftereffects of transcranial direct current stimulation: An fMRI study. Hum Brain Mapp 2019; 41:1644-1666. [PMID: 31860160 PMCID: PMC7267945 DOI: 10.1002/hbm.24901] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 11/11/2019] [Accepted: 12/04/2019] [Indexed: 01/03/2023] Open
Abstract
Transcranial direct current stimulation (tDCS) induces polarity‐ and dose‐dependent neuroplastic aftereffects on cortical excitability and cortical activity, as demonstrated by transcranial magnetic stimulation (TMS) and functional imaging (fMRI) studies. However, lacking systematic comparative studies between stimulation‐induced changes in cortical excitability obtained from TMS, and cortical neurovascular activity obtained from fMRI, prevent the extrapolation of respective physiological and mechanistic bases. We investigated polarity‐ and intensity‐dependent effects of tDCS on cerebral blood flow (CBF) using resting‐state arterial spin labeling (ASL‐MRI), and compared the respective changes to TMS‐induced cortical excitability (amplitudes of motor evoked potentials, MEP) in separate sessions within the same subjects (n = 29). Fifteen minutes of sham, 0.5, 1.0, 1.5, and 2.0‐mA anodal or cathodal tDCS was applied over the left primary motor cortex (M1) in a randomized repeated‐measure design. Time‐course changes were measured before, during and intermittently up to 120‐min after stimulation. ROI analyses indicated linear intensity‐ and polarity‐dependent tDCS after‐effects: all anodal‐M1 intensities increased CBF under the M1 electrode, with 2.0‐mA increasing CBF the greatest (15.3%) compared to sham, while all cathodal‐M1 intensities decreased left M1 CBF from baseline, with 2.0‐mA decreasing the greatest (−9.3%) from sham after 120‐min. The spatial distribution of perfusion changes correlated with the predicted electric field, as simulated with finite element modeling. Moreover, tDCS‐induced excitability changes correlated more strongly with perfusion changes in the left sensorimotor region compared to the targeted hand‐knob region. Our findings reveal lasting tDCS‐induced alterations in cerebral perfusion, which are dose‐dependent with tDCS parameters, but only partially account for excitability changes.
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Affiliation(s)
- Asif Jamil
- Department Psychology and Neurosciences, Leibniz Research Centre for Working Environment and Human Factors, Dortmund, Germany.,REVAL Research Institute, University of Hasselt, Hasselt, Belgium
| | - Giorgi Batsikadze
- Department of Neurology, Essen University Hospital, University of Duisburg-Essen, Essen, Germany
| | - Hsiao-I Kuo
- Department Psychology and Neurosciences, Leibniz Research Centre for Working Environment and Human Factors, Dortmund, Germany
| | - Raf L J Meesen
- REVAL Research Institute, University of Hasselt, Hasselt, Belgium
| | - Peter Dechent
- Department of Cognitive Neurology, University Medical Center, University of Göttingen, Göttingen, Germany
| | - Walter Paulus
- Department of Clinical Neurophysiology, University Medical Center, University of Göttingen, Göttingen, Germany
| | - Michael A Nitsche
- Department Psychology and Neurosciences, Leibniz Research Centre for Working Environment and Human Factors, Dortmund, Germany.,Department of Neurology, University Medical Hospital Bergmannsheil, Bochum, Germany
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29
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Delorme M, Vergotte G, Perrey S, Froger J, Laffont I. Time course of sensorimotor cortex reorganization during upper extremity task accompanying motor recovery early after stroke: An fNIRS study. Restor Neurol Neurosci 2019; 37:207-218. [PMID: 31227675 DOI: 10.3233/rnn-180877] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
BACKGROUND The acute phase of stroke is accompanied by functional changes and interplay of both hemispheres. However, our understanding of how the time course of upper limb functional motor recovery is related to the progression of brain reorganization in the sensorimotor areas remains limited. This study aimed to assess the time course of hemodynamic patterns of cortical sensorimotor areas using functional near infrared spectroscopy (fNIRS) and motor recovery within three months after a stroke. METHOD Eight right-handed first ischemic/hemorrhagic stroke patients (60±8 years, 3 women) with mild to severe hemiparesis were examined with repetitive fNIRS measurements and motor recovery tests (Fugl-Meyer score) during two months. Hemodynamic changes over the ipsilesional and contralesional sensorimotor areas were collected from a multi-channel fNIRS system during intermittent isometric muscle contractions at self-selected submaximal force levels for each arm. Lateralization index was computed to evaluate the changes in the interhemispheric balance between the cortical sensorimotor areas. RESULTS Lateralization index values during non-paretic arm movements showed no significant changes over time in patients and were comparable to those observed in eight healthy controls. Paretic-arm movements were associated early with a bilateral cortical activity before shifting to ipsilesional patterns (p < 0.01). Progressive lateralization observed over the two months (p < 0.05) evolved concomitantly with an increase in the Fugl-Meyer score (p < 0.001). CONCLUSIONS Cortical reorganization monitoring using fNIRS during the first weeks after stroke may be applied for assessing progressive brain plasticity in addition to clinical measures of performance.
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Affiliation(s)
- Marion Delorme
- EuroMov, Univ. Montpellier, Montpellier, France.,Nîmes University Hospital, Department of Physical Medicine and Rehabilitation, Nîmes, France
| | | | | | - Jérôme Froger
- EuroMov, Univ. Montpellier, Montpellier, France.,Nîmes University Hospital, Department of Physical Medicine and Rehabilitation, Nîmes, France
| | - Isabelle Laffont
- EuroMov, Univ. Montpellier, Montpellier, France.,Montpellier University Hospital, Department of Physical Medicine and Rehabilitation, Montpellier, France
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30
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Fiori V, Nitsche MA, Cucuzza G, Caltagirone C, Marangolo P. High-Definition Transcranial Direct Current Stimulation Improves Verb Recovery in Aphasic Patients Depending on Current Intensity. Neuroscience 2019; 406:159-166. [PMID: 30876982 DOI: 10.1016/j.neuroscience.2019.03.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 02/24/2019] [Accepted: 03/06/2019] [Indexed: 12/28/2022]
Abstract
High-definition transcranial direct current stimulation (HD-tDCS) is a variant of tDCS, which produces more focal stimulation, delimiting brain current flow to a defined region compared to conventional tDCS. To date, only one study has been conducted to investigate HD-tDCS effects on language recovery in aphasia. Here, we aimed to assess the effects of cathodal HD-tDCS on verb naming by comparing two current intensities: 1 vs 2 mA. In a double-blinded cross over study, two groups of 10 aphasic individuals were submitted to active cathodal HD-tDCS and sham stimulation over the right homolog of Broca's area, while performing a verb naming task. Indeed, we reasoned that, by applying inhibitory current over the right Broca's area, we would decrease the inhibitory impact from the right hemisphere to the left perilesional cortex, thus boosting language recovery. The groups differed in the intensity of the active stimulation (1 mA or 2 mA). In both groups, each condition was carried out in five consecutive daily sessions with one week of interval between the two experimental conditions. A significant improvement in verb naming was found only after cathodal HD-tDCS at 2 mA, which endured one week after the end of treatment. The improvement was not observed on the group receiving cathodal HD-tDCS at 1 mA. Our findings showed that HD-tDCS applied to the right intact hemisphere are efficacious for language recovery. These results indicate that HD-tDCS represents a promising new technique for language rehabilitation. However, systematic determination of stimulation intensity appears to be crucial for obtaining relevant effects.
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Affiliation(s)
| | - Michael A Nitsche
- Department Psychology and Neurosciences, Leibniz Research Center for Working Environment and Human Factors, Dortmund, Germany; Department of Neurology, BG University Hospital Bergmannsheil, Bochum, Germany
| | | | - Carlo Caltagirone
- IRCCS, Fondazione Santa Lucia, Rome, Italy; Università degli Studi di Tor Vergata, Rome, Italy
| | - Paola Marangolo
- IRCCS, Fondazione Santa Lucia, Rome, Italy; Università Federico II, Naples, Italy.
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31
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Cancel LM, Arias K, Bikson M, Tarbell JM. Direct current stimulation of endothelial monolayers induces a transient and reversible increase in transport due to the electroosmotic effect. Sci Rep 2018; 8:9265. [PMID: 29915178 PMCID: PMC6006334 DOI: 10.1038/s41598-018-27524-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 05/29/2018] [Indexed: 12/25/2022] Open
Abstract
We investigated the effects of direct current stimulation (DCS) on fluid and solute transport across endothelial cell (EC) monolayers in vitro. Our motivation was transcranial direct current stimulation (tDCS) that has been investigated for treatment of neuropsychiatric disorders, to enhance neurorehabilitation, and to change cognition in healthy subjects. The mechanisms underlying this diversity of applications remain under investigation. To address the possible role of blood-brain barrier (BBB) changes during tDCS, we applied direct current to cultured EC monolayers in a specially designed chamber that generated spatially uniform direct current. DCS induced fluid and solute movement across EC layers that persisted only for the duration of the stimulation suggesting an electroosmosis mechanism. The direction of induced transport reversed with DCS polarity - a hallmark of the electroosmotic effect. The magnitude of DCS-induced flow was linearly correlated to the magnitude of the applied current. A mathematical model based on a two-pore description of the endothelial transport barrier and a Helmholtz model of the electrical double layer describes the experimental data accurately and predicts enhanced significance of this mechanism in less permeable monolayers. This study demonstrates that DCS transiently alters the transport function of the BBB suggesting a new adjunct mechanism of tDCS.
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Affiliation(s)
- Limary M Cancel
- Department of Biomedical Engineering, The City College of New York, New York, USA
| | - Katherin Arias
- Department of Biomedical Engineering, The City College of New York, New York, USA
| | - Marom Bikson
- Department of Biomedical Engineering, The City College of New York, New York, USA
| | - John M Tarbell
- Department of Biomedical Engineering, The City College of New York, New York, USA.
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32
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Berger A, Pixa NH, Steinberg F, Doppelmayr M. Brain Oscillatory and Hemodynamic Activity in a Bimanual Coordination Task Following Transcranial Alternating Current Stimulation (tACS): A Combined EEG-fNIRS Study. Front Behav Neurosci 2018; 12:67. [PMID: 29720935 PMCID: PMC5915568 DOI: 10.3389/fnbeh.2018.00067] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 03/23/2018] [Indexed: 11/13/2022] Open
Abstract
Motor control is associated with synchronized oscillatory activity at alpha (8–12 Hz) and beta (12–30 Hz) frequencies in a cerebello-thalamo-cortical network. Previous studies demonstrated that transcranial alternating current stimulation (tACS) is capable of entraining ongoing oscillatory activity while also modulating motor control. However, the modulatory effects of tACS on both motor control and its underlying electro- and neurophysiological mechanisms remain ambiguous. Thus, the purpose of this study was to contribute to gathering neurophysiological knowledge regarding tACS effects by investigating the after-effects of 10 Hz tACS and 20 Hz tACS at parietal brain areas on bimanual coordination and its concurrent oscillatory and hemodynamic activity. Twenty-four right-handed healthy volunteers (12 females) aged between 18 and 30 (M = 22.35 ± 3.62) participated in the study and performed a coordination task requiring bimanual movements. Concurrent to bimanual motor training, participants received either 10 Hz tACS, 20 Hz tACS or a sham stimulation over the parietal cortex (at P3/P4 electrode positions) for 20 min via small gel electrodes (3,14 cm2 Ag/AgCl, amperage = 1 mA). Before and three time-points after tACS (immediately, 30 min and 1 day), bimanual coordination performance was assessed. Oscillatory activities were measured by electroencephalography (EEG) and hemodynamic changes were examined using functional near-infrared spectroscopy (fNIRS). Improvements of bimanual coordination performance were not differently between groups, thus, no tACS-specific effect on bimanual coordination performance emerged. However, physiological measures during the task revealed significant increases in parietal alpha activity immediately following 10 Hz tACS and 20 Hz tACS which were accompanied by significant decreases of Hboxy concentration in the right hemispheric motor cortex compared to the sham group. Based on the physiological responses, we conclude that tACS applied at parietal brain areas provoked electrophysiological and hemodynamic changes at brain regions of the motor network which are relevant for bimanual motor behavior. The existence of neurophysiological alterations immediately following tACS, especially in the absence of behavioral effects, are elementary for a profound understanding of the mechanisms underlying tACS. The lack of behavioral modifications strengthens the need for further research on tACS effects on neurophysiology and behavior using combined electrophysiological and neuroimaging methods.
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Affiliation(s)
- Alisa Berger
- Department of Sports Psychology, Institute of Sport Science, Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Nils H Pixa
- Department of Sports Psychology, Institute of Sport Science, Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Fabian Steinberg
- Department of Sports Psychology, Institute of Sport Science, Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Michael Doppelmayr
- Department of Sports Psychology, Institute of Sport Science, Johannes Gutenberg-University Mainz, Mainz, Germany.,Centre for Cognitive Neuroscience, Paris Lodron University of Salzburg, Salzburg, Austria
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33
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Baxter BS, Edelman BJ, Sohrabpour A, He B. Anodal Transcranial Direct Current Stimulation Increases Bilateral Directed Brain Connectivity during Motor-Imagery Based Brain-Computer Interface Control. Front Neurosci 2017; 11:691. [PMID: 29270110 PMCID: PMC5725434 DOI: 10.3389/fnins.2017.00691] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Accepted: 11/23/2017] [Indexed: 01/29/2023] Open
Abstract
Transcranial direct current stimulation (tDCS) has been shown to affect motor and cognitive task performance and learning when applied to brain areas involved in the task. Targeted stimulation has also been found to alter connectivity within the stimulated hemisphere during rest. However, the connectivity effect of the interaction of endogenous task specific activity and targeted stimulation is unclear. This study examined the aftereffects of concurrent anodal high-definition tDCS over the left sensorimotor cortex with motor network connectivity during a one-dimensional EEG based sensorimotor rhythm brain-computer interface (SMR-BCI) task. Directed connectivity following anodal tDCS illustrates altered connections bilaterally between frontal and parietal regions, and these alterations occur in a task specific manner; connections between similar cortical regions are altered differentially during left and right imagination trials. During right-hand imagination following anodal tDCS, there was an increase in outflow from the left premotor cortex (PMC) to multiple regions bilaterally in the motor network and increased inflow to the stimulated sensorimotor cortex from the ipsilateral PMC and contralateral sensorimotor cortex. During left-hand imagination following anodal tDCS, there was increased outflow from the stimulated sensorimotor cortex to regions across the motor network. Significant correlations between connectivity and the behavioral measures of total correct trials and time-to-hit (TTH) correct trials were also found, specifically that the input to the left PMC correlated with decreased right hand imagination performance and that flow from the ipsilateral posterior parietal cortex (PPC) to midline sensorimotor cortex correlated with improved performance for both right and left hand imagination. These results indicate that tDCS interacts with task-specific endogenous activity to alter directed connectivity during SMR-BCI. In order to predict and maximize the targeted effect of tDCS, the interaction of stimulation with the dynamics of endogenous activity needs to be examined comprehensively and understood.
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Affiliation(s)
- Bryan S. Baxter
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, United States
| | - Bradley J. Edelman
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, United States
| | - Abbas Sohrabpour
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, United States
| | - Bin He
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, United States
- Institute for Engineering in Medicine, University of Minnesota, Minneapolis, MN, United States
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34
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Perceval G, Martin AK, Copland DA, Laine M, Meinzer M. High-definition tDCS of the temporo-parietal cortex enhances access to newly learned words. Sci Rep 2017; 7:17023. [PMID: 29208991 PMCID: PMC5717109 DOI: 10.1038/s41598-017-17279-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 11/23/2017] [Indexed: 11/16/2022] Open
Abstract
Learning associations between words and their referents is crucial for language learning in the developing and adult brain and for language re-learning after neurological injury. Non-invasive transcranial direct current stimulation (tDCS) to the posterior temporo-parietal cortex has been suggested to enhance this process. However, previous studies employed standard tDCS set-ups that induce diffuse current flow in the brain, preventing the attribution of stimulation effects to the target region. This study employed high-definition tDCS (HD-tDCS) that allowed the current flow to be constrained to the temporo-parietal cortex, to clarify its role in novel word learning. In a sham-controlled, double-blind, between-subjects design, 50 healthy adults learned associations between legal non-words and unfamiliar object pictures. Participants were stratified by baseline learning ability on a short version of the learning paradigm and pairwise randomized to active (20 mins; N = 25) or sham (40 seconds; N = 25) HD-tDCS. Accuracy was comparable during the baseline and experimental phases in both HD-tDCS conditions. However, active HD-tDCS resulted in faster retrieval of correct word-picture pairs. Our findings corroborate the critical role of the temporo-parietal cortex in novel word learning, which has implications for current theories of language acquisition.
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Affiliation(s)
- Garon Perceval
- The University of Queensland, Centre for Clinical Research, Brisbane, Australia
| | - Andrew K Martin
- The University of Queensland, Centre for Clinical Research, Brisbane, Australia
| | - David A Copland
- The University of Queensland, Centre for Clinical Research, Brisbane, Australia.,The University of Queensland, School of Rehabilitation Sciences, Brisbane, Australia
| | - Matti Laine
- Åbo Akademi University, Department of Psychology, Turku, Finland
| | - Marcus Meinzer
- The University of Queensland, Centre for Clinical Research, Brisbane, Australia.
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35
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Jackson MP, Bikson M, Liebetanz D, Nitsche M. How to consider animal data in tDCS safety standards. Brain Stimul 2017; 10:1141-1142. [PMID: 28851553 DOI: 10.1016/j.brs.2017.08.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 08/13/2017] [Indexed: 12/28/2022] Open
Affiliation(s)
- Mark P Jackson
- 711th Human Performance Wing, Air Force Research Laboratory, Wright Patterson AFB, OH 45433, United States; Department of Biomedical Engineering, The City College of The City University of New York, CDI Building, 85 St. Nicholas Terrace, New York, NY 10031, United States
| | - Marom Bikson
- Department of Biomedical Engineering, The City College of The City University of New York, CDI Building, 85 St. Nicholas Terrace, New York, NY 10031, United States.
| | - David Liebetanz
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Georg August University, Göttingen, Germany
| | - Michael Nitsche
- Department of Psychology and Neurosciences, Leibniz Research Centre for Working Environment and Human Factors, Dortmund, Germany
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