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Jiang Y, Ramasawmy P, Antal A. Uncorking the limitation-improving dual tasking using transcranial electrical stimulation and task training in the elderly: a systematic review. Front Aging Neurosci 2024; 16:1267307. [PMID: 38650865 PMCID: PMC11033383 DOI: 10.3389/fnagi.2024.1267307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 03/22/2024] [Indexed: 04/25/2024] Open
Abstract
Introduction With aging, dual task (DT) ability declines and is more cognitively demanding than single tasks. Rapidly declining DT performance is regarded as a predictor of neurodegenerative disease. Task training and non-invasive transcranial electrical stimulation (tES) are methods applied to optimize the DT ability of the elderly. Methods A systematic search was carried out in the PUBMED, TDCS (transcranial direct current stimulation) databases, as well as Web of Science, and a qualitative analysis was conducted in 56 included studies. Aiming to summarize the results of studies that implemented tES, task training, or the combination for improving DT ability and related performance changes in healthy elderly and geriatric patients. For different approaches, the training procedures, parameters, as well as outcomes were discussed. Results Task training, particularly cognitive-motor DT training, has more notable effects on improving DT performance in the elderly when compared to the neuromodulation method. Discussion Anodal transcranial direct current stimulation (tDCS) over the left dorsolateral prefrontal cortex (L-DLPFC), or its combination with task training could be promising tools. However, additional evidence is required from aged healthy people and patients, as well as further exploration of electrode montage.
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Affiliation(s)
- Yong Jiang
- Department of Neurology, University Medical Center, Georg August University of Göttingen, Göttingen, Germany
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Rivera-Urbina GN, Molero-Chamizo A, Nitsche MA. Discernible effects of tDCS over the primary motor and posterior parietal cortex on different stages of motor learning. Brain Struct Funct 2022; 227:1115-1131. [PMID: 35037127 DOI: 10.1007/s00429-021-02451-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 12/29/2021] [Indexed: 11/28/2022]
Abstract
Implicit motor learning and memory involve complex cortical and subcortical networks. The induction of plasticity in these network components via non-invasive brain stimulation, including transcranial direct current stimulation (tDCS), has shown to improve motor learning. However, studies showing these effects are mostly restricted to stimulation of the primary motor cortex (M1) during the early stage of learning. Because of this, we aimed to explore the efficacy of anodal tDCS applied over the posterior parietal cortex (PPC), which is involved in memory processes, on serial reaction time task (SRTT) performance. Specifically, to evaluate the involvement of both motor learning network components, we compared the effects of tDCS applied over regions corresponding to M1 and PPC during the early and late stages of learning. The results revealed a selective improvement of reaction time (RT) during anodal stimulation over the PPC in the late stage of learning. These findings support the assumption that the PPC is relevant during specific phases of learning, at least for SRTT performance. The results also indicate that not only the target area (i.e., PPC), but also timing is crucial for achieving the effects of stimulation on motor learning.
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Affiliation(s)
- Guadalupe Nathzidy Rivera-Urbina
- Autonomous University of Baja California, Blvd Juan A Zertuche y Blvd de los Lagos s/n Fracc, Valle Dorado, C.P. 22890, Ensenada, Baja California, México.
| | | | - Michael A Nitsche
- Leibniz Research Centre for Working Environment and Human Factors, Dortmund, Germany.,Department of Neurology, University Medical Hospital Bergmannsheil, Bochum, Germany
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Dissanayaka T, Zoghi M, Farrell M, Egan G, Jaberzadeh S. The effects of monophasic anodal transcranial pulsed current stimulation on corticospinal excitability and motor performance in healthy young adults: A randomized double-blind sham-controlled study. Brain Connect 2021; 12:260-274. [PMID: 34963309 DOI: 10.1089/brain.2020.0949] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
INTRODUCTION Transcranial pulsed current stimulation (tPCS) could be used to deliver electrical pulses at different frequencies to entrain the cortical neurons of the brain. Frequency dependence of these pulses in the induction of changes in corticospinal excitability (CSE) has not been reported. OBJECTIVE We aimed to assess the effect of anodal tPCS (a-tPCS) at theta (4 Hz), and gamma (75 Hz) frequencies on CSE as assessed by the peak-to-peak amplitude of transcranial magnetic stimulation (TMS) induced motor evoked potentials (MEPs) and motor performance. METHOD In a randomized double-blinded sham-controlled cross over design study, seventeen healthy participants attended three experimental sessions and received either a-tPCS at 4 Hz, 75 Hz, or sham a-tPCS with 1.5 mA for 15 min. The amplitude of TMS induced resting MEPs and time for completion of the grooved pegboard test were recorded at baseline, immediately after, and 30-min after a-tPCS. RESULTS Both a-tPCS at 75 Hz and 4 Hz showed significantly increased CSE compared to sham. The a-tPCS at 75 Hz induced significantly higher CSE changes compared to 4 Hz. There was a significant increase in intracortical facilitation and a significant reduction in short-interval intra-cortical inhibition with both 4 and 75 Hz stimulation. However, the inhibition and facilitation did not correlate with CSE. Motor performance was unaffected by the interventions. CONCLUSION The high CSE changes in M1 in a-tPCS at 75 Hz provides an initial understanding of the frequency-specific effect of a-tPCS. More research is needed to establish this concept and to assess its behavioural relevance.
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Affiliation(s)
- Thusharika Dissanayaka
- Monash University, 2541, 6/63, Frankston-flinders road, Frankston, Frankston, Victoria, Australia, 3199;
| | - Maryam Zoghi
- La Trobe University, 2080, Melbourne, Victoria, Australia;
| | - Michael Farrell
- Monash University, 2541, Medical Imaging and Radiation Sciences, Wellington Road, Clayton, Victoria, Australia, 3800.,Monash University;
| | - Gary Egan
- Monash University, Monash Biomedical Imaging; School of Psychological Sciences, Melbourne, Victoria, Australia.,ARC Centre of Excellence for Integrative Brain Function, Melbourne, Australia;
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Using high-definition transcranial direct current stimulation to investigate the role of the dorsolateral prefrontal cortex in explicit sequence learning. PLoS One 2021; 16:e0246849. [PMID: 33735211 PMCID: PMC7971701 DOI: 10.1371/journal.pone.0246849] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 01/26/2021] [Indexed: 11/19/2022] Open
Abstract
Though we have a general understanding of the brain areas involved in motor sequence learning, there is more to discover about the neural mechanisms underlying skill acquisition. Skill acquisition may be subserved, in part, by interactions between the cerebellum and prefrontal cortex through a cerebello-thalamo-prefrontal network. In prior work, we investigated this network by targeting the cerebellum; here, we explored the consequence of stimulating the dorsolateral prefrontal cortex using high-definition transcranial direct current stimulation (HD-tDCS) before administering an explicit motor sequence learning paradigm. Using a mixed within- and between- subjects design, we employed anodal (n = 24) and cathodal (n = 25) HD-tDCS (relative to sham) to temporarily alter brain function and examine effects on skill acquisition. The results indicate that both anodal and cathodal prefrontal stimulation impedes motor sequence learning, relative to sham. These findings suggest an overall negative influence of active prefrontal stimulation on the acquisition of a sequential pattern of finger movements. Collectively, this provides novel insight on the role of the dorsolateral prefrontal cortex in initial skill acquisition, when cognitive processes such as working memory are used. Exploring methods that may improve motor learning is important in developing therapeutic strategies for motor-related diseases and rehabilitation.
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Pellegrini M, Zoghi M, Jaberzadeh S. Can genetic polymorphisms predict response variability to anodal transcranial direct current stimulation of the primary motor cortex? Eur J Neurosci 2020; 53:1569-1591. [PMID: 33048398 DOI: 10.1111/ejn.15002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Revised: 09/17/2020] [Accepted: 10/02/2020] [Indexed: 11/28/2022]
Abstract
Genetic mediation of cortical plasticity and the role genetic variants play in previously observed response variability to transcranial direct current stimulation (tDCS) have become important issues in the tDCS literature in recent years. This study investigated whether inter-individual variability to tDCS was in-part genetically mediated. In 61 healthy males, anodal-tDCS (a-tDCS) and sham-tDCS were administered to the primary motor cortex at 1 mA for 10-min via 6 × 4 cm active and 7 × 5 cm return electrodes. Twenty-five single-pulse transcranial magnetic stimulation (TMS) motor evoked potentials (MEP) were recorded to represent corticospinal excitability (CSE). Twenty-five paired-pulse MEPs were recorded with 3 ms inter-stimulus interval (ISI) to assess intracortical inhibition (ICI) via short-interval intracranial inhibition (SICI) and 10 ms ISI for intracortical facilitation (ICF). Saliva samples were tested for specific genetic polymorphisms in genes encoding for excitatory and inhibitory neuroreceptors. Individuals were sub-grouped based on a pre-determined threshold and via statistical cluster analysis. Two distinct subgroups were identified, increases in CSE following a-tDCS (i.e. Responders) and no increase or even reductions in CSE (i.e. Non-responders). No changes in ICI or ICF were reported. No relationships were reported between genetic polymorphisms in excitatory receptor genes and a-tDCS responders. An association was reported between a-tDCS responders and GABRA3 gene polymorphisms encoding for GABA-A receptors suggesting potential relationships between GABA-A receptor variations and capacity to undergo tDCS-induced cortical plasticity. In the largest tDCS study of its kind, this study presents an important step forward in determining the contribution genetic factors play in previously observed inter-individual variability to tDCS.
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Affiliation(s)
- Michael Pellegrini
- Non-Invasive Brain Stimulation and Neuroplasticity Laboratory, Department of Physiotherapy, School of Primary and Allied Health Care, Faculty of Medicine, Nursing and Health Science, Monash University, Melbourne, Australia
| | - Maryam Zoghi
- Department of Rehabilitation, Nutrition and Sport, School of Allied Health, Discipline of Physiotherapy, La Trobe University, Melbourne, Australia
| | - Shapour Jaberzadeh
- Non-Invasive Brain Stimulation and Neuroplasticity Laboratory, Department of Physiotherapy, School of Primary and Allied Health Care, Faculty of Medicine, Nursing and Health Science, Monash University, Melbourne, Australia
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Pellegrini M, Zoghi M, Jaberzadeh S. A Checklist to Reduce Response Variability in Studies Using Transcranial Magnetic Stimulation for Assessment of Corticospinal Excitability: A Systematic Review of the Literature. Brain Connect 2020; 10:53-71. [PMID: 32093486 DOI: 10.1089/brain.2019.0715] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Response variability between individuals (interindividual variability) and within individuals (intraindividual variability) is an important issue in the transcranial magnetic stimulation (TMS) literature. This has raised questions of the validity of TMS to assess changes in corticospinal excitability (CSE) in a predictable and reliable manner. Several participant-specific factors contribute to this observed response variability with a current lack of consensus on the degree each factor contributes. This highlights a need for consistency and structure in reporting study designs and methodologies. Currently, there is no summarized review of the participant-specific factors that can be controlled and may contribute to response variability. This systematic review aimed to develop a checklist of methodological measures taken by previously published research to increase the homogeneity of participant selection criteria, preparation of participants before experimental testing, participant scheduling, and the instructions given to participants throughout experimental testing to minimize their effect on response variability. Seven databases were searched in full. Studies were included if CSE was measured via TMS and included methodological measures to increase the homogeneity of the participants. Eighty-four studies were included. Twenty-three included measures to increase participant selection homogeneity, 21 included measures to increase participant preparation homogeneity, while 61 included measures to increase participant scheduling and instructions during experimental testing homogeneity. These methodological measures were summarized into a user-friendly checklist with considerations, suggestions, and rationale/justification for their inclusion. This may provide the framework for further insights into ways to reduce response variability in TMS research.
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Affiliation(s)
- Michael Pellegrini
- Non-Invasive Brain Stimulation and Neuroplasticity Laboratory, Department of Physiotherapy, School of Primary and Allied Health Care, Faculty of Medicine, Nursing and Health Science, Monash University, Melbourne, Victoria, Australia
| | - Maryam Zoghi
- Department of Rehabilitation, Nutrition and Sport, Discipline of Physiotherapy, School of Allied Health, La Trobe University, Melbourne, Victoria, Australia
| | - Shapour Jaberzadeh
- Non-Invasive Brain Stimulation and Neuroplasticity Laboratory, Department of Physiotherapy, School of Primary and Allied Health Care, Faculty of Medicine, Nursing and Health Science, Monash University, Melbourne, Victoria, Australia
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Pollok B, Keitel A, Foerster M, Moshiri G, Otto K, Krause V. The posterior parietal cortex mediates early offline-rather than online-motor sequence learning. Neuropsychologia 2020; 146:107555. [PMID: 32653440 DOI: 10.1016/j.neuropsychologia.2020.107555] [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: 01/28/2020] [Revised: 06/23/2020] [Accepted: 07/04/2020] [Indexed: 12/13/2022]
Abstract
Learning of new motor skills occurs particularly during training on a task (i.e. online) but has been observed between training-blocks lasting up to days after the end of the training (i.e. offline). Offline-learning occurs as further improvement in task performance indicated by increased accuracy and/or faster responses as well as less interference with respect to a distracting condition. Successful motor learning requires the functional interplay between cortical as well as subcortical brain areas. While the involvement of the primary motor cortex in online-as well as early offline-learning is well established, the functional significance of the posterior parietal cortex (PPC) is less clear. Since the PPC may act as sensory-motor interface, a causal involvement in motor learning is conceivable. In order to characterize the functional significance of the left PPC for motor sequence learning, transcranial direct current stimulation (tDCS) was applied either immediately prior to, during or immediately after training on a serial reaction time task (SRTT) in a total of 54 healthy volunteers. While the analysis did not provide evidence for a significant modulation of reaction times during SRTT training (i.e. online-learning), cathodal tDCS decelerated reaction times of the learned sequences as compared to anodal and sham stimulation 30 min after the end of training. The findings suggest that cathodal tDCS over the left parietal cortex interferes with the reproduction of learned sequences.
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Affiliation(s)
- Bettina Pollok
- Heinrich-Heine University Duesseldorf, Medical Faculty, Institute of Clinical Neuroscience and Medical Psychology, Germany.
| | - Ariane Keitel
- Heinrich-Heine University Duesseldorf, Medical Faculty, Institute of Clinical Neuroscience and Medical Psychology, Germany
| | - Maike Foerster
- Heinrich-Heine University Duesseldorf, Medical Faculty, Institute of Clinical Neuroscience and Medical Psychology, Germany
| | - Geraldine Moshiri
- Heinrich-Heine University Duesseldorf, Medical Faculty, Institute of Clinical Neuroscience and Medical Psychology, Germany
| | - Katharina Otto
- Heinrich-Heine University Duesseldorf, Medical Faculty, Institute of Clinical Neuroscience and Medical Psychology, Germany
| | - Vanessa Krause
- Heinrich-Heine University Duesseldorf, Medical Faculty, Institute of Clinical Neuroscience and Medical Psychology, Germany; Mauritius Hospital Meerbusch, Department of Neuropsychology, Germany
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Alsultan F, Alaboudi M, Almousa A, Alajaji R, Bashir S. Effects of transcranial direct current stimulation over frontal, parietal and cerebellar cortex for cognitive function during fasting in healthy adults. IBRO Rep 2020; 8:129-135. [PMID: 32435717 PMCID: PMC7231976 DOI: 10.1016/j.ibror.2020.03.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Accepted: 03/19/2020] [Indexed: 11/30/2022] Open
Abstract
Background Transcranial direct current stimulation (tDCS) is a neuromodulation tool used to modify the cognitive function in subjects. There is a paucity of data on tDCS' effect on cognitive function during Ramadan fasting. This paper aims to assess the effect of tDCS of three brain areas, including the right dorsolateral prefrontal cortex (DLPFC), posterior parietal cortex (PPC), and cerebellum on cognitive function, and obtain safety data in healthy adults during Ramadan fasting. Methods and material A total of 42 healthy, right-handed participants were randomly assigned to one of the 6 stimulation groups: active (anodal)-tDCS of right DLPFC, PPC, and cerebellum; or sham for DLPFC, PPC, and cerebellum after 8 h of fasting for Ramadan. Safety data and cognitive function, such as attention-switching tasks (AST), were obtained by employing the Cambridge Neuropsychological Test Automated Battery (CANTAB) before and after each tDCS session. The cognitive function outcome variables were the response time and the percentage of correct answers in AST. For sham stimulation, the placement of the electrodes was the same as for the active stimulation. Results An improvement in performance time in attention tasks was observed; however, it did not reach a significant level after anodal stimulation of the DLPFC, PPC, and cerebellum. Overall, there were no statistically significant differences between the active and sham tDCS groups in cognitive function. There were no significant side effects of tDCS during fasting for any group. Conclusions Our data suggest that there are variable effects of tDCS on attention tasks during Ramadan fasting. TDCS appears to be safe, well-tolerated and adhered to the international standard of safety in the local population during Ramadan fasting. Further large sample size studies should be conducted to validate the current study findings and reach better conclusions.
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Affiliation(s)
- Fahad Alsultan
- Department of Medicine, King Saud Medical City, Riyadh, Saudi Arabia.,Prince Sultan Military Medical City, Riyadh, Saudi Arabia
| | - Malak Alaboudi
- Department of Medicine, King Saud Medical City, Riyadh, Saudi Arabia
| | - Abdullah Almousa
- Department of Medicine, King Saud Medical City, Riyadh, Saudi Arabia
| | - Reema Alajaji
- Department of radiology, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Shahid Bashir
- Neuroscience Center, King Fahad Specialist Hospital, Dammam, Saudi Arabia
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Primary motor cortex function and motor skill acquisition: insights from threshold-hunting TMS. Exp Brain Res 2020; 238:1745-1757. [DOI: 10.1007/s00221-020-05791-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 03/18/2020] [Indexed: 12/11/2022]
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Acquisition of chopstick-operation skills with the non-dominant hand and concomitant changes in brain activity. Sci Rep 2019; 9:20397. [PMID: 31892724 PMCID: PMC6938489 DOI: 10.1038/s41598-019-56956-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 12/18/2019] [Indexed: 01/07/2023] Open
Abstract
Despite their common use as eating utensils in East Asia, chopsticks require complex fine motor-skills for adequate operation and are thus most frequently used with the dominant hand; however, the effect of training time on the proficiency of using chopsticks with the non-dominant hand, as well as the brain activity underlying changes in skill, remain unclear. This study characterised the effect of time spent training in chopstick operation with the non-dominant hand on chopstick-use proficiency and the related brain activity to obtain data that may help individuals who are obliged to change handedness due to neurological disease to learn to use their non-dominant hand in performing daily activities. Thirty-two healthy right-handed students were randomly allocated to training (n = 16) or control (n = 16) groups; the former received 6 weeks of training in chopstick use with their non-dominant (left) hand, and the latter received none. After training, significant improvements in the execution speed and smoothness of upper extremity joints were observed in the training group. Moreover, left dorsolateral prefrontal cortex activity significantly decreased, and bilateral premotor cortex activity significantly increased across training. These results indicated that 6 weeks of chopstick training with the non-dominant hand effectively improved chopstick operation.
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Patel R, Ashcroft J, Patel A, Ashrafian H, Woods AJ, Singh H, Darzi A, Leff DR. The Impact of Transcranial Direct Current Stimulation on Upper-Limb Motor Performance in Healthy Adults: A Systematic Review and Meta-Analysis. Front Neurosci 2019; 13:1213. [PMID: 31803003 PMCID: PMC6873898 DOI: 10.3389/fnins.2019.01213] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 10/28/2019] [Indexed: 11/25/2022] Open
Abstract
Background: Transcranial direct current stimulation (tDCS) has previously been reported to improve facets of upper limb motor performance such as accuracy and strength. However, the magnitude of motor performance improvement has not been reviewed by contemporaneous systematic review or meta-analysis of sham vs. active tDCS. Objective: To systematically review and meta-analyse the existing evidence regarding the benefits of tDCS on upper limb motor performance in healthy adults. Methods: A systematic search was conducted to obtain relevant articles from three databases (MEDLINE, EMBASE, and PsycINFO) yielding 3,200 abstracts. Following independent assessment by two reviewers, a total of 86 articles were included for review, of which 37 were deemed suitable for meta-analysis. Results: Meta-analyses were performed for four outcome measures, namely: reaction time (RT), execution time (ET), time to task failure (TTF), and force. Further qualitative review was performed for accuracy and error. Statistically significant improvements in RT (effect size −0.01; 95% CI −0.02 to 0.001, p = 0.03) and ET (effect size −0.03; 95% CI −0.05 to −0.01, p = 0.017) were demonstrated compared to sham. In exercise tasks, increased force (effect size 0.10; 95% CI 0.08 to 0.13, p < 0.001) and a trend towards improved TTF was also observed. Conclusions: This meta-analysis provides evidence attesting to the impact of tDCS on upper limb motor performance in healthy adults. Improved performance is demonstrable in reaction time, task completion time, elbow flexion tasks and accuracy. Considerable heterogeneity exists amongst the literature, further confirming the need for a standardised approach to reporting tDCS studies.
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Affiliation(s)
- Ronak Patel
- Department of Surgery & Cancer, Imperial College London, London, United Kingdom
| | - James Ashcroft
- Department of Surgery & Cancer, Imperial College London, London, United Kingdom
| | - Ashish Patel
- Department of Surgery & Cancer, Imperial College London, London, United Kingdom
| | - Hutan Ashrafian
- Department of Surgery & Cancer, Imperial College London, London, United Kingdom
| | - Adam J Woods
- Department of Clinical and Health Psychology, Center for Cognitive Aging and Memory, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
| | - Harsimrat Singh
- Department of Surgery & Cancer, Imperial College London, London, United Kingdom
| | - Ara Darzi
- Department of Surgery & Cancer, Imperial College London, London, United Kingdom
| | - Daniel Richard Leff
- Department of Surgery & Cancer, Imperial College London, London, United Kingdom
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