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Fresnoza S, Ischebeck A. Probing Our Built-in Calculator: A Systematic Narrative Review of Noninvasive Brain Stimulation Studies on Arithmetic Operation-Related Brain Areas. eNeuro 2024; 11:ENEURO.0318-23.2024. [PMID: 38580452 PMCID: PMC10999731 DOI: 10.1523/eneuro.0318-23.2024] [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: 08/25/2023] [Revised: 02/06/2024] [Accepted: 02/26/2024] [Indexed: 04/07/2024] Open
Abstract
This systematic review presented a comprehensive survey of studies that applied transcranial magnetic stimulation and transcranial electrical stimulation to parietal and nonparietal areas to examine the neural basis of symbolic arithmetic processing. All findings were compiled with regard to the three assumptions of the triple-code model (TCM) of number processing. Thirty-seven eligible manuscripts were identified for review (33 with healthy participants and 4 with patients). Their results are broadly consistent with the first assumption of the TCM that intraparietal sulcus both hold a magnitude code and engage in operations requiring numerical manipulations such as subtraction. However, largely heterogeneous results conflicted with the second assumption of the TCM that the left angular gyrus subserves arithmetic fact retrieval, such as the retrieval of rote-learned multiplication results. Support is also limited for the third assumption of the TCM, namely, that the posterior superior parietal lobule engages in spatial operations on the mental number line. Furthermore, results from the stimulation of brain areas outside of those postulated by the TCM show that the bilateral supramarginal gyrus is involved in online calculation and retrieval, the left temporal cortex in retrieval, and the bilateral dorsolateral prefrontal cortex and cerebellum in online calculation of cognitively demanding arithmetic problems. The overall results indicate that multiple cortical areas subserve arithmetic skills.
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Affiliation(s)
- Shane Fresnoza
- Department of Psychology, University of Graz, 8010 Graz, Austria
- BioTechMed, 8010 Graz, Austria
| | - Anja Ischebeck
- Department of Psychology, University of Graz, 8010 Graz, Austria
- BioTechMed, 8010 Graz, Austria
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2
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Farshad M, Artemenko C, Cipora K, Svaldi J, Schroeder PA. Regional specificity of cathodal transcranial direct current stimulation effects on spatial-numerical associations: Comparison of four stimulation sites. J Neurosci Res 2024; 102:e25304. [PMID: 38361404 DOI: 10.1002/jnr.25304] [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: 10/20/2023] [Revised: 12/21/2023] [Accepted: 01/24/2024] [Indexed: 02/17/2024]
Abstract
Neuromodulation with transcranial direct current stimulation (tDCS) is an increasingly popular research tool to experimentally manipulate cortical areas and probe their causal involvements in behavior, but its replicability and regional specificity are not clear. This registered report investigated cathodal tDCS effects on spatial-numerical associations (i.e., the SNARC effect), the numerical distance effect (NDE), and inhibitory control (i.e., stop-signal reaction time; SSRT). Healthy adults (N = 160) were randomly assigned to one of five groups to receive sham tDCS or 1 mA cathodal tDCS to one of four stimulation sites (left/right prefrontal cortex [PFC], left/right posterior parietal cortex) with extracephalic return. We replicated that cathodal tDCS over the left PFC reduced the SNARC effect compared to sham tDCS and to tDCS over the left parietal cortex. However, neither NDE nor SSRT were modulated in the main analyses. Post hoc contrasts and exploratory analyses showed that cathodal tDCS over the right PFC had a time-dependent effect by delayed practice-related improvements in SSRT. Math anxiety moderated changes in the NDE in the groups receiving tDCS to the right parietal cortex. With few exceptions, the replicability and regional specificity of tDCS effects on behavior were weak and partially moderated by individual differences. Future research needs to characterize the parameter settings for effective neuromodulation.
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Affiliation(s)
- Maryam Farshad
- Department of Psychology, University of Tuebingen, Tuebingen, Germany
| | - Christina Artemenko
- Department of Psychology, University of Tuebingen, Tuebingen, Germany
- LEAD Research Network, University of Tuebingen, Tuebingen, Germany
| | - Krzysztof Cipora
- Department of Psychology, University of Tuebingen, Tuebingen, Germany
- LEAD Research Network, University of Tuebingen, Tuebingen, Germany
- Centre for Mathematical Cognition, Loughborough University, Loughborough, UK
| | - Jennifer Svaldi
- Department of Psychology, University of Tuebingen, Tuebingen, Germany
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3
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Hussain M, Davis NJ, Benn Y. A single tDCS session can enhance numerical competence. Neuropsychologia 2024; 193:108760. [PMID: 38103681 DOI: 10.1016/j.neuropsychologia.2023.108760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 12/05/2023] [Accepted: 12/11/2023] [Indexed: 12/19/2023]
Abstract
While numerical skills are increasingly important in modern life, few interventions have been developed to support those with numeracy skills difficulties. Previous studies have demonstrated that applying transcranial Direct Current Stimulation (tDCS) can improve numerical skills. However, tDCS interventions designed to induce lasting changes typically involve reapplying brain-stimulation over several days. Repeated tDCS application can increase the risks associated with the procedure, as well as restricts the transferability of the method to a wider population, particularly those who may experience mobility issues, such as stroke survivors with acalculia. The current study investigated whether a single session of tDCS (anodal to right parietal lobe and cathodal to left parietal lobe), followed by four self-practice sessions without tDCS, could result in enhancement of numerical skills. Nineteen healthy adults (n = 10 tDCS, n = 9 sham control) implicitly learnt the magnitude association of nine arbitrary symbols, previously used by Cohen Kadosh et al. (2010). Numerical proficiency was assessed using number-to-space task, while automaticity was assessed with numerical Stroop. Results revealed that single-session tDCS had a significant effect on participants' accuracy on the number-to-space tasks, but not on the numerical Stroop task's congruity effect, implying automaticity may require longer practice. We conclude that a single session of tDCS should be considered as an avenue for interventions.
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Affiliation(s)
- Maryam Hussain
- School of Health Sciences, University of Manchester, Manchester, M13 9PL, United Kingdom; Department of Psychology, Manchester Metropolitan University, Manchester, M15 6GX, United Kingdom
| | - Nick J Davis
- Department of Psychology, Manchester Metropolitan University, Manchester, M15 6GX, United Kingdom
| | - Yael Benn
- Department of Psychology, Manchester Metropolitan University, Manchester, M15 6GX, United Kingdom.
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4
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Bahreini N, Artemenko C, Plewnia C, Nuerk HC. tDCS effects in basic symbolic number magnitude processing are not significantly lateralized. Sci Rep 2023; 13:21515. [PMID: 38057342 PMCID: PMC10700326 DOI: 10.1038/s41598-023-48189-z] [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: 08/04/2023] [Accepted: 11/23/2023] [Indexed: 12/08/2023] Open
Abstract
Functional lateralization was previously established for various cognitive domains-but not for number processing. Although numbers are considered to be bilaterally represented in the intraparietal sulcus (IPS), there are some indications of different functional roles of the left vs. right IPS in processing number pairs with small vs. large distance, respectively. This raises the question whether number size plays a distinct role in the lateralization within the IPS. In our preregistered study, we applied anodal transcranial direct current stimulation (tDCS) over the left vs. right IPS to investigate the effect of stimulation as compared to sham on small vs. large distance, in both single-digit and two-digit number comparison. We expected that anodal tDCS over the left IPS facilitates number comparison with small distance, while anodal tDCS over the right IPS facilitates number comparison with large distance. Results indicated no effect of stimulation; however, exploratory analyses revealed that tDCS over the right IPS slowed down single-digit number processing after controlling for the training effect. In conclusion, number magnitude processing might be bilaterally represented in the IPS, however, our exploratory analyses emphasise the need for further investigation on functional lateralization of number processing.
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Affiliation(s)
- Narjes Bahreini
- Department of Psychology, University of Tuebingen, Tuebingen, Germany.
| | | | - Christian Plewnia
- Department of Psychiatry and Psychotherapy, Neurophysiology and Interventional Neuropsychiatry, University Hospital of Tuebingen, Tuebingen, Germany
- German Centre for Mental Health (DZPG), Jena, Germany
| | - Hans-Christoph Nuerk
- Department of Psychology, University of Tuebingen, Tuebingen, Germany
- German Centre for Mental Health (DZPG), Jena, Germany
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5
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Khan A, Mosbacher JA, Vogel SE, Binder M, Wehovz M, Moshammer A, Halverscheid S, Pustelnik K, Nitsche MA, Tong RKY, Grabner RH. Modulation of resting-state networks following repetitive transcranial alternating current stimulation of the dorsolateral prefrontal cortex. Brain Struct Funct 2023; 228:1643-1655. [PMID: 37436503 PMCID: PMC10471656 DOI: 10.1007/s00429-023-02667-2] [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: 03/17/2023] [Accepted: 06/12/2023] [Indexed: 07/13/2023]
Abstract
Transcranial alternating current stimulation (tACS) offers a unique method to temporarily manipulate the activity of the stimulated brain region in a frequency-dependent manner. However, it is not clear if repetitive modulation of ongoing oscillatory activity with tACS over multiple days can induce changes in grey matter resting-state functional connectivity and white matter structural integrity. The current study addresses this question by applying multiple-session theta band stimulation on the left dorsolateral prefrontal cortex (L-DLPFC) during arithmetic training. Fifty healthy participants (25 males and 25 females) were randomly assigned to the experimental and sham groups, half of the participants received individually adjusted theta band tACS, and half received sham stimulation. Resting-state functional magnetic resonance (rs-fMRI) and diffusion-weighted imaging (DWI) data were collected before and after 3 days of tACS-supported procedural learning training. Resting-state network analysis showed a significant increase in connectivity for the frontoparietal network (FPN) with the precuneus cortex. Seed-based analysis with a seed defined at the primary stimulation site showed an increase in connectivity with the precuneus cortex, posterior cingulate cortex (PCC), and lateral occipital cortex. There were no effects on the structural integrity of white matter tracts as measured by fractional anisotropy, and on behavioral measures. In conclusion, the study suggests that multi-session task-associated tACS can produce significant changes in resting-state functional connectivity; however, changes in functional connectivity do not necessarily translate to changes in white matter structure or behavioral performance.
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Affiliation(s)
- Ahsan Khan
- Educational Neuroscience, Institute of Psychology, University of Graz, Graz, Austria
- Biomedical Engineering Department, The Chinese University of Hong Kong, Hong Kong, China
| | - Jochen A Mosbacher
- Educational Neuroscience, Institute of Psychology, University of Graz, Graz, Austria
| | - Stephan E Vogel
- Educational Neuroscience, Institute of Psychology, University of Graz, Graz, Austria
| | - Mira Binder
- Educational Neuroscience, Institute of Psychology, University of Graz, Graz, Austria
| | - Michael Wehovz
- Educational Neuroscience, Institute of Psychology, University of Graz, Graz, Austria
| | - Arnulf Moshammer
- Educational Neuroscience, Institute of Psychology, University of Graz, Graz, Austria
| | | | - Kolja Pustelnik
- Mathematics Institute, University of Göttingen, Göttingen, Germany
| | - Michael A Nitsche
- Department of Psychology and Neurosciences, Leibniz Research Centre for Working Environment and Human Factors, Dortmund, Germany
- Protestant Hospital of Bethel Foundation, Bielefeld University, University Hospital OWL, University Clinic of Psychiatry and Psychotherapy and University Clinic of Child and Adolescent Psychiatry and Psychotherapy, Bielefeld, Germany
| | - Raymond Kai-Yu Tong
- Biomedical Engineering Department, The Chinese University of Hong Kong, Hong Kong, China.
| | - Roland H Grabner
- Educational Neuroscience, Institute of Psychology, University of Graz, Graz, Austria.
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Lazzaro G, Fucà E, Caciolo C, Battisti A, Costanzo F, Varuzza C, Vicari S, Menghini D. Understanding the Effects of Transcranial Electrical Stimulation in Numerical Cognition: A Systematic Review for Clinical Translation. J Clin Med 2022; 11:jcm11082082. [PMID: 35456176 PMCID: PMC9032363 DOI: 10.3390/jcm11082082] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Revised: 03/31/2022] [Accepted: 04/02/2022] [Indexed: 02/04/2023] Open
Abstract
Atypical development of numerical cognition (dyscalculia) may increase the onset of neuropsychiatric symptoms, especially when untreated, and it may have long-term detrimental social consequences. However, evidence-based treatments are still lacking. Despite plenty of studies investigating the effects of transcranial electrical stimulation (tES) on numerical cognition, a systematized synthesis of results is still lacking. In the present systematic review (PROSPERO ID: CRD42021271139), we found that the majority of reports (20 out of 26) showed the effectiveness of tES in improving both number (80%) and arithmetic (76%) processing. In particular, anodal tDCS (regardless of lateralization) over parietal regions, bilateral tDCS (regardless of polarity/lateralization) over frontal regions, and tRNS (regardless of brain regions) strongly enhance number processing. While bilateral tDCS and tRNS over parietal and frontal regions and left anodal tDCS over frontal regions consistently improve arithmetic skills. In addition, tACS seems to be more effective than tDCS at ameliorating arithmetic learning. Despite the variability of methods and paucity of clinical studies, tES seems to be a promising brain-based treatment to enhance numerical cognition. Recommendations for clinical translation, future directions, and limitations are outlined.
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Affiliation(s)
- Giulia Lazzaro
- Child and Adolescent Neuropsychiatry Unit, Department of Neuroscience, Bambino Gesù Children’s Hospital, IRCCS, 00146 Rome, Italy; (G.L.); (E.F.); (C.C.); (A.B.); (F.C.); (C.V.); (S.V.)
| | - Elisa Fucà
- Child and Adolescent Neuropsychiatry Unit, Department of Neuroscience, Bambino Gesù Children’s Hospital, IRCCS, 00146 Rome, Italy; (G.L.); (E.F.); (C.C.); (A.B.); (F.C.); (C.V.); (S.V.)
| | - Cristina Caciolo
- Child and Adolescent Neuropsychiatry Unit, Department of Neuroscience, Bambino Gesù Children’s Hospital, IRCCS, 00146 Rome, Italy; (G.L.); (E.F.); (C.C.); (A.B.); (F.C.); (C.V.); (S.V.)
| | - Andrea Battisti
- Child and Adolescent Neuropsychiatry Unit, Department of Neuroscience, Bambino Gesù Children’s Hospital, IRCCS, 00146 Rome, Italy; (G.L.); (E.F.); (C.C.); (A.B.); (F.C.); (C.V.); (S.V.)
- Department of Human Science, LUMSA University, 00193 Rome, Italy
| | - Floriana Costanzo
- Child and Adolescent Neuropsychiatry Unit, Department of Neuroscience, Bambino Gesù Children’s Hospital, IRCCS, 00146 Rome, Italy; (G.L.); (E.F.); (C.C.); (A.B.); (F.C.); (C.V.); (S.V.)
| | - Cristiana Varuzza
- Child and Adolescent Neuropsychiatry Unit, Department of Neuroscience, Bambino Gesù Children’s Hospital, IRCCS, 00146 Rome, Italy; (G.L.); (E.F.); (C.C.); (A.B.); (F.C.); (C.V.); (S.V.)
| | - Stefano Vicari
- Child and Adolescent Neuropsychiatry Unit, Department of Neuroscience, Bambino Gesù Children’s Hospital, IRCCS, 00146 Rome, Italy; (G.L.); (E.F.); (C.C.); (A.B.); (F.C.); (C.V.); (S.V.)
- Department of Life Science and Public Health, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
- Centro di Riabilitazione Casa San Giuseppe, Opera Don Guanella, 00165 Rome, Italy
| | - Deny Menghini
- Child and Adolescent Neuropsychiatry Unit, Department of Neuroscience, Bambino Gesù Children’s Hospital, IRCCS, 00146 Rome, Italy; (G.L.); (E.F.); (C.C.); (A.B.); (F.C.); (C.V.); (S.V.)
- Correspondence: ; Tel.: +39-066-859-7091
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Ashkenazi S, Tikochinski R, Ganor-Stern D. Neural Correlates of Numerical Estimation: The Role of Strategy Use. Brain Sci 2022; 12:brainsci12030357. [PMID: 35326313 PMCID: PMC8945989 DOI: 10.3390/brainsci12030357] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Revised: 02/14/2022] [Accepted: 03/02/2022] [Indexed: 02/06/2023] Open
Abstract
Introduction: Computation estimation is the ability to provide an approximate answer to a complex arithmetic problem without calculating it exactly. Despite its importance in daily life, the neuronal network underlying computation estimation is largely unknown. Methods: We looked at the neuronal correlates of two computational estimation strategies: approximated calculation and sense of magnitude (SOM)–intuitive representation of magnitude, without calculation. During an fMRI scan, thirty-one college students judged whether the result of a two-digit multiplication problem was larger or smaller than a given reference number. In two different blocks, they were asked to use a specific strategy (AC or SOM). Results: The two strategies activated brain regions related to calculation, numerical cognition, decision-making, and working memory. AC more than SOM elicited activations in multiple, domain-specific brain regions in the parietal lobule, including the left SMG (BA 40), the bilateral superior parietal lobule (BA 7), and the right inferior parietal lobule (BA 7). The activation level of the IFG was positively correlated to individual accuracy, indicating that the IFG has an essential role in both strategies. Conclusions: These finding suggest that the analogic code of magnitude is more involved in the AC than the SOM strategy.
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Affiliation(s)
- Sarit Ashkenazi
- Learning Disabilities, The Seymour Fox School of Education, The Hebrew University of Jerusalem, Jerusalem 9190501, Israel
- Correspondence: ; Tel.: +972-2-5882-058
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Khan A, Yuan K, Bao SC, Ti CHE, Tariq A, Anjum N, Tong RKY. Can Transcranial Electrical Stimulation Facilitate Post-stroke Cognitive Rehabilitation? A Systematic Review and Meta-Analysis. FRONTIERS IN REHABILITATION SCIENCES 2022; 3:795737. [PMID: 36188889 PMCID: PMC9397778 DOI: 10.3389/fresc.2022.795737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 01/11/2022] [Indexed: 01/12/2023]
Abstract
Background Non-invasive brain stimulation methods have been widely utilized in research settings to manipulate and understand the functioning of the human brain. In the last two decades, transcranial electrical stimulation (tES) has opened new doors for treating impairments caused by various neurological disorders. However, tES studies have shown inconsistent results in post-stroke cognitive rehabilitation, and there is no consensus on the effectiveness of tES devices in improving cognitive skills after the onset of stroke. Objectives We aim to systematically investigate the efficacy of tES in improving post-stroke global cognition, attention, working memory, executive functions, visual neglect, and verbal fluency. Furthermore, we aim to provide a pathway to an effective use of stimulation paradigms in future studies. Methods Preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines were followed. Randomized controlled trials (RCTs) were systematically searched in four different databases, including Medline, Embase, Pubmed, and PsychInfo. Studies utilizing any tES methods published in English were considered for inclusion. Standardized mean difference (SMD) for each cognitive domain was used as the primary outcome measure. Results The meta-analysis includes 19 studies assessing at least one of the six cognitive domains. Five RCTs studying global cognition, three assessing visual neglect, five evaluating working memory, three assessing attention, and nine studies focusing on aphasia were included for meta-analysis. As informed by the quantitative analysis of the included studies, the results favor the efficacy of tES in acute improvement in aphasic deficits (SMD = 0.34, CI = 0.02-0.67, p = 0.04) and attention deficits (SMD = 0.59, CI = -0.05-1.22, p = 0.07), however, no improvement was observed in any other cognitive domains. Conclusion The results favor the efficacy of tES in an improvement in aphasia and attentive deficits in stroke patients in acute, subacute, and chronic stages. However, the outcome of tES cannot be generalized across cognitive domains. The difference in the stimulation montages and parameters, diverse cognitive batteries, and variable number of training sessions may have contributed to the inconsistency in the outcome. We suggest that in future studies, experimental designs should be further refined, and standardized stimulation protocols should be utilized to better understand the therapeutic effect of stimulation.
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Affiliation(s)
- Ahsan Khan
- Biomedical Engineering Department, The Chinese University of Hong Kong, Hong Kong, China
| | - Kai Yuan
- Biomedical Engineering Department, The Chinese University of Hong Kong, Hong Kong, China
| | - Shi-Chun Bao
- National Innovation Center for Advanced Medical Devices, Shenzhen, China
| | - Chun Hang Eden Ti
- Biomedical Engineering Department, The Chinese University of Hong Kong, Hong Kong, China
| | - Abdullah Tariq
- Department of Electrical Engineering, Pakistan Institute of Engineering and Applied Sciences, Islamabad, Pakistan
| | - Nimra Anjum
- Department of Electrical Engineering, Pakistan Institute of Engineering and Applied Sciences, Islamabad, Pakistan
| | - Raymond Kai-Yu Tong
- Biomedical Engineering Department, The Chinese University of Hong Kong, Hong Kong, China,Hong Kong Brain and Mind Institute, The Chinese University of Hong Kong, Hong Kong, China,*Correspondence: Raymond Kai-Yu Tong
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9
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Mosbacher JA, Halverscheid S, Pustelnik K, Danner M, Prassl C, Brunner C, Vogel SE, Nitsche MA, Grabner RH. Theta Band Transcranial Alternating Current Stimulation Enhances Arithmetic Learning: A Systematic Comparison of Different Direct and Alternating Current Stimulations. Neuroscience 2021; 477:89-105. [PMID: 34648868 DOI: 10.1016/j.neuroscience.2021.10.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 10/01/2021] [Accepted: 10/04/2021] [Indexed: 11/17/2022]
Abstract
Over the last decades, interest in transcranial electrical stimulation (tES) has grown, as it might allow for causal investigations of the associations between cortical activity and cognition as well as to directly influence cognitive performance. The main objectives of the present work were to assess whether tES can enhance the acquisition and application of arithmetic abilities, and whether it enables a better assessment of underlying neurophysiological processes. To this end, the present, double-blind, sham-controlled study assessed the effects of six active stimulations (three tES protocols: anodal transcranial direct current stimulation (tDCS), alpha band transcranial alternating current stimulation (tACS), and theta band tACS; targeting the left dorsolateral prefrontal cortex or the left posterior parietal cortex) on the acquisition of an arithmetic procedure, arithmetic facts, and event-related synchronization/desynchronization (ERS/ERD) patterns. 137 healthy adults were randomly assigned to one of seven groups, each receiving one of the tES-protocols during learning. Results showed that frontal theta band tACS reduced the repetitions needed to learn novel facts and both, frontal and parietal theta band tACS accelerated the decrease in calculation times in fact learning problems. The beneficial effect of frontal theta band tACS may reflect enhanced executive functions, allowing for better control and inhibition processes and hence, a faster acquisition and integration of novel fact knowledge. However, there were no significant effects of the stimulations on procedural learning or ERS/ERD patterns. Overall, theta band tACS appears promising as a support for arithmetic fact training, but effects on procedural calculations and neurophysiological processes remain ambiguous.
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Affiliation(s)
- Jochen A Mosbacher
- Section of Educational Neuroscience, Institute of Psychology, University of Graz, Graz, Austria.
| | | | - Kolja Pustelnik
- Mathematics Institute, University of Göttingen, Göttingen, Germany
| | - Martina Danner
- Section of Educational Neuroscience, Institute of Psychology, University of Graz, Graz, Austria
| | - Christina Prassl
- Section of Educational Neuroscience, Institute of Psychology, University of Graz, Graz, Austria
| | - Clemens Brunner
- Section of Educational Neuroscience, Institute of Psychology, University of Graz, Graz, Austria
| | - Stephan E Vogel
- Section of Educational Neuroscience, Institute of Psychology, University of Graz, Graz, Austria
| | - Michael A Nitsche
- Department of Psychology and Neurosciences, Leibniz Research Centre for Working Environment and Human Factors, Dortmund, Germany; Department of Neurology, University Medical Hospital Bergmannsheil, Ruhr-University Bochum, Bochum, Germany
| | - Roland H Grabner
- Section of Educational Neuroscience, Institute of Psychology, University of Graz, Graz, Austria; BioTechMed Graz, Graz, Austria
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10
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van Bueren NER, Reed TL, Nguyen V, Sheffield JG, van der Ven SHG, Osborne MA, Kroesbergen EH, Cohen Kadosh R. Personalized brain stimulation for effective neurointervention across participants. PLoS Comput Biol 2021; 17:e1008886. [PMID: 34499639 PMCID: PMC8454957 DOI: 10.1371/journal.pcbi.1008886] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 09/21/2021] [Accepted: 08/10/2021] [Indexed: 11/24/2022] Open
Abstract
Accumulating evidence from human-based research has highlighted that the prevalent one-size-fits-all approach for neural and behavioral interventions is inefficient. This approach can benefit one individual, but be ineffective or even detrimental for another. Studying the efficacy of the large range of different parameters for different individuals is costly, time-consuming and requires a large sample size that makes such research impractical and hinders effective interventions. Here an active machine learning technique is presented across participants-personalized Bayesian optimization (pBO)-that searches available parameter combinations to optimize an intervention as a function of an individual's ability. This novel technique was utilized to identify transcranial alternating current stimulation (tACS) frequency and current strength combinations most likely to improve arithmetic performance, based on a subject's baseline arithmetic abilities. The pBO was performed across all subjects tested, building a model of subject performance, capable of recommending parameters for future subjects based on their baseline arithmetic ability. pBO successfully searches, learns, and recommends parameters for an effective neurointervention as supported by behavioral, simulation, and neural data. The application of pBO in human-based research opens up new avenues for personalized and more effective interventions, as well as discoveries of protocols for treatment and translation to other clinical and non-clinical domains.
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Affiliation(s)
- Nienke E. R. van Bueren
- Wellcome Centre for Integrative Neuroimaging, Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom
- Behavioural Science Institute, Radboud University Nijmegen, Nijmegen, the Netherlands
| | - Thomas L. Reed
- Wellcome Centre for Integrative Neuroimaging, Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom
| | - Vu Nguyen
- Department of Materials, University of Oxford, Oxford, United Kingdom
- Amazon, Adelaide, Australia
| | - James G. Sheffield
- Wellcome Centre for Integrative Neuroimaging, Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom
| | | | - Michael A. Osborne
- Department of Engineering Science, University of Oxford, Oxford, United Kingdom
| | - Evelyn H. Kroesbergen
- Behavioural Science Institute, Radboud University Nijmegen, Nijmegen, the Netherlands
| | - Roi Cohen Kadosh
- Wellcome Centre for Integrative Neuroimaging, Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom
- School of Psychology, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
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11
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Fresnoza S, Christova M, Purgstaller S, Jehna M, Zaar K, Hoffermann M, Mahdy Ali K, Körner C, Gallasch E, von Campe G, Ischebeck A. Dissociating Arithmetic Operations in the Parietal Cortex Using 1 Hz Repetitive Transcranial Magnetic Stimulation: The Importance of Strategy Use. Front Hum Neurosci 2020; 14:271. [PMID: 32765240 PMCID: PMC7378795 DOI: 10.3389/fnhum.2020.00271] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 06/16/2020] [Indexed: 11/13/2022] Open
Abstract
The triple-code model (TCM) of number processing suggests the involvement of distinct parietal cortex areas in arithmetic operations: the bilateral horizontal segment of the intraparietal sulcus (hIPS) for arithmetic operations that require the manipulation of numerical quantities (e.g., subtraction) and the left angular gyrus (AG) for arithmetic operations that require the retrieval of answers from long-term memory (e.g., multiplication). Although neuropsychological, neuroimaging, and brain stimulation studies suggest the dissociation of these operations into distinct parietal cortex areas, the role of strategy (online calculation vs. retrieval) is not yet fully established. In the present study, we further explored the causal involvement of the left AG for multiplication and left hIPS for subtraction using a neuronavigated repetitive transcranial magnetic stimulation (rTMS) paradigm. Stimulation sites were determined based on an fMRI experiment using the same tasks. To account for the effect of strategy, participants were asked whether they used retrieval or calculation for each individual problem. We predicted that the stimulation of the left AG would selectively disrupt the retrieval of the solution to multiplication problems. On the other hand, stimulation of the left hIPS should selectively disrupt subtraction. Our results revealed that left AG stimulation was detrimental to the retrieval and online calculation of solutions for multiplication problems, as well as, the retrieval (but not online calculation) of the solutions to subtraction problems. In contrast, left hIPS stimulation had no detrimental effect on both operations regardless of strategy.
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Affiliation(s)
- Shane Fresnoza
- Institute of Psychology, University of Graz, Graz, Austria.,BioTechMed, Graz, Austria
| | - Monica Christova
- Otto Loewi Research Center, Physiology Section, Medical University of Graz, Graz, Austria.,Department of Physiotherapy, University of Applied Sciences FH-Joanneum Graz, Graz, Austria
| | | | - Margit Jehna
- Department of Radiology, Medical University of Graz, Graz, Austria
| | - Karla Zaar
- Department of Neurosurgery, Medical University of Graz, Graz, Austria
| | - Markus Hoffermann
- Department of Neurosurgery, Medical University of Graz, Graz, Austria
| | - Kariem Mahdy Ali
- Department of Neurosurgery, Medical University of Graz, Graz, Austria
| | - Christof Körner
- Institute of Psychology, University of Graz, Graz, Austria.,BioTechMed, Graz, Austria
| | - Eugen Gallasch
- BioTechMed, Graz, Austria.,Otto Loewi Research Center, Physiology Section, Medical University of Graz, Graz, Austria
| | - Gord von Campe
- Department of Neurosurgery, Medical University of Graz, Graz, Austria
| | - Anja Ischebeck
- Institute of Psychology, University of Graz, Graz, Austria.,BioTechMed, Graz, Austria
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12
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Mosbacher JA, Brunner C, Nitsche MA, Grabner RH. Effects of Anodal tDCS on Arithmetic Performance and Electrophysiological Activity. Front Hum Neurosci 2020; 14:17. [PMID: 32116605 PMCID: PMC7026470 DOI: 10.3389/fnhum.2020.00017] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 01/17/2020] [Indexed: 11/13/2022] Open
Abstract
Arithmetic abilities are among the most important school-taught skills and form the basis for higher mathematical competencies. At the same time, their acquisition and application can be challenging. Hence, there is broad interest in methods to improve arithmetic abilities. One promising method is transcranial direct current stimulation (tDCS). In the present study, we compared two anodal tDCS protocols in their efficacy to improve arithmetic performance and working memory. In addition, we investigated stimulation-related electrophysiological changes. Three groups of participants solved arithmetic problems (additions and subtractions) and an n-back task before, during, and after receiving either frontal or parietal anodal tDCS (25 min; 1 mA) or sham stimulation. EEG was simultaneously recorded to assess stimulation effects on event-related (de-) synchronisation (ERS/ERD) in theta and alpha bands. Persons receiving frontal stimulation showed an acceleration of calculation speed in large subtractions from before to during and after stimulation. However, a comparable, but delayed (apparent only after stimulation) increase was also found in the sham stimulation group, while it was absent in the group receiving parietal stimulation. In additions and small subtractions as well as the working memory task, analyses showed no effects of stimulation. Results of ERS/ERD during large subtractions indicate changes in ERS/ERD patterns over time. In the left hemisphere there was a change from theta band ERD to ERS in all three groups, whereas a similar change in the right hemisphere was restricted to the sham group. Taken together, tDCS did not lead to a general improvement of arithmetic performance. However, results indicate that frontal stimulation accelerated training gains, while parietal stimulation halted them. The absence of general performance improvements, but acceleration of training effects might be a further indicator of the advantages of using tDCS as training or learning support over tDCS as a sole performance enhancer.
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Affiliation(s)
- Jochen A. Mosbacher
- Educational Neuroscience, Institute of Psychology, University of Graz, Graz, Austria
| | - Clemens Brunner
- Educational Neuroscience, Institute of Psychology, University of Graz, Graz, Austria
| | - Michael A. Nitsche
- Department of Psychology and Neurosciences, Leibniz Research Centre for Working Environment and Human Factors, Dortmund, Germany
- Department of Neurology, University Medical Hospital Bergmannsheil, Ruhr-University Bochum, Bochum, Germany
| | - Roland H. Grabner
- Educational Neuroscience, Institute of Psychology, University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
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13
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Artemenko C, Sitnikova MA, Soltanlou M, Dresler T, Nuerk HC. Functional lateralization of arithmetic processing in the intraparietal sulcus is associated with handedness. Sci Rep 2020; 10:1775. [PMID: 32020021 PMCID: PMC7000739 DOI: 10.1038/s41598-020-58477-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 01/15/2020] [Indexed: 01/06/2023] Open
Abstract
Functional lateralization is established for various cognitive functions, but was hardly ever investigated for arithmetic processing. Most neurocognitive models assume a central role of the bilateral intraparietal sulcus (IPS) in arithmetic processing and there is some evidence for more pronounced left-hemispheric activation for symbolic arithmetic. However, evidence was mainly obtained by studies in right-handers. Therefore, we conducted a functional near-infrared spectroscopy (fNIRS) study, in which IPS activation of left-handed adults was compared to right-handed adults in a symbolic approximate calculation task. The results showed that left-handers had a stronger functional right-lateralization in the IPS than right-handers. This finding has important consequences, as the bilateral IPS activation pattern for arithmetic processing seems to be shaped by functional lateralization and thus differs between left- and right-handers. We propose three possible accounts for the observed functional lateralization of arithmetic processing.
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Affiliation(s)
- Christina Artemenko
- Department of Psychology, University of Tuebingen, Tuebingen, Germany.
- LEAD Graduate School & Research Network, University of Tuebingen, Tuebingen, Germany.
| | - Maria A Sitnikova
- Department of Psychology, Pedagogical Institute, Belgorod National Research University, Belgorod, Russia
- Research and Project Centre for Cognitive Neuroscience and Neurotechnologies, Belgorod National Research University, Belgorod, Russia
| | - Mojtaba Soltanlou
- Department of Psychology, University of Tuebingen, Tuebingen, Germany
- LEAD Graduate School & Research Network, University of Tuebingen, Tuebingen, Germany
| | - Thomas Dresler
- LEAD Graduate School & Research Network, University of Tuebingen, Tuebingen, Germany
- Department of Psychiatry and Psychotherapy, University of Tuebingen, Tuebingen, Germany
| | - Hans-Christoph Nuerk
- Department of Psychology, University of Tuebingen, Tuebingen, Germany
- LEAD Graduate School & Research Network, University of Tuebingen, Tuebingen, Germany
- Research and Project Centre for Cognitive Neuroscience and Neurotechnologies, Belgorod National Research University, Belgorod, Russia
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14
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Hartmann M, Singer S, Savic B, Müri RM, Mast FW. Anodal High-definition Transcranial Direct Current Stimulation over the Posterior Parietal Cortex Modulates Approximate Mental Arithmetic. J Cogn Neurosci 2019; 32:862-876. [PMID: 31851594 DOI: 10.1162/jocn_a_01514] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The representation and processing of numerosity is a crucial cognitive capacity. Converging evidence points to the posterior parietal cortex (PPC) as primary "number" region. However, the exact role of the left and right PPC for different types of numerical and arithmetic tasks remains controversial. In this study, we used high-definition transcranial direct current stimulation (HD-tDCS) to further investigate the causal involvement of the PPC during approximative, nonsymbolic mental arithmetic. Eighteen healthy participants received three sessions of anodal HD-tDCS at 1-week intervals in counterbalanced order: left PPC, right PPC, and sham stimulation. Results showed an improved performance during online parietal HD-tDCS (vs. sham) for subtraction problems. Specifically, the general tendency to underestimate the results of subtraction problems (i.e., the "operational momentum effect") was reduced during online parietal HD-tDCS. There was no difference between left and right stimulation. This study thus provides new evidence for a causal involvement of the left and right PPC for approximate nonsymbolic arithmetic and advances the promising use of noninvasive brain stimulation in increasing cognitive functions.
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15
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Schroeder PA, Artemenko C, Cipora K, Svaldi J. Regional specificity of cathodal transcranial direct current stimulation (tDCS) effects on spatial-numerical associations: Comparison of four stimulation sites. J Neurosci Res 2019; 98:655-667. [PMID: 31785042 DOI: 10.1002/jnr.24559] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 10/16/2019] [Accepted: 10/30/2019] [Indexed: 11/09/2022]
Abstract
Based on a theory of impulsive and reflective human behavior, we test the effects of transcranial direct current stimulation (tDCS) targeting either prefrontal or parietal cortex in either hemisphere. In a confirmatory registered report, cathodal tDCS is administered to conceptually reproduce tDCS modulations of implicit spatial-numerical associations, numerical distance effects, and response inhibition. Those cognitive operations are hypothesized to draw on left prefrontal, parietal, and right prefrontal activations, respectively, thereby susceptible to inhibitory, cathodal tDCS across those regions. Vice versa, the mutual regional and behavioral specificity of tDCS effects on these behavioral indices is examined and expected to produce double dissociations. In a mixed within-subjects (baseline, during tDCS, post-tDCS) and between-subjects (target electrode: left/right prefrontal cortex/posterior parietal cortex, or sham tDCS) design, we collect (a) confirmatory data on the robustness of cathodal tDCS effects on three behavioral effects and (b) differential data on the specificity of regional targets in male and female human participants. Results will provide crucial tests of theories of cortical organization implied by implicit associations and explicit regulation, which can direct future brain stimulation studies.
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Affiliation(s)
| | - Christina Artemenko
- Department of Psychology, University of Tübingen, Tübingen, Germany.,LEAD Research Network, University of Tübingen, Tübingen, Germany
| | - Krzysztof Cipora
- Department of Psychology, University of Tübingen, Tübingen, Germany.,LEAD Research Network, University of Tübingen, Tübingen, Germany
| | - Jennifer Svaldi
- Department of Psychology, University of Tübingen, Tübingen, Germany
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16
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17
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Bieck SM, Artemenko C, Moeller K, Klein E. Low to No Effect: Application of tRNS During Two-Digit Addition. Front Neurosci 2018; 12:176. [PMID: 29674948 PMCID: PMC5895770 DOI: 10.3389/fnins.2018.00176] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Accepted: 03/05/2018] [Indexed: 01/02/2023] Open
Abstract
Transcranial electric stimulation such as transcranial random noise stimulation (tRNS) and transcranial direct current stimulation (tDCS) have been used to investigate structure-function relationships in numerical cognition. Recently, tRNS was suggested to be more effective than tDCS. However, so far there is no evidence on the differential impact of tDCS and tRNS on numerical cognition using the same experimental paradigm. In the present study, we used a two-digit addition paradigm for which significant-albeit small-effects of tDCS were observed previously to evaluate the impact of parietal and frontal tRNS on specific numerical effects. While previous studies reported a modulation of numerical effects of this task through tDCS applied to parietal areas, we did not observe any effect of parietal tRNS on performance in two-digit addition. These findings suggest that tRNS seemed to influence concurrent mental arithmetic less than tDCS at least when applied over the IPS. These generally small to absent effects of tES on actual arithmetic performance in the current addition paradigm are in line with the results of a recent meta-analysis indicating that influences of tES may be more pronounced in training paradigms.
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Affiliation(s)
- Silke M Bieck
- LEAD Graduate School & Research Network, University of Tuebingen, Tuebingen, Germany.,Leibniz-Institut für Wissensmedien, Tuebingen, Germany
| | - Christina Artemenko
- LEAD Graduate School & Research Network, University of Tuebingen, Tuebingen, Germany.,Department of Psychology, University of Tuebingen, Tuebingen, Germany
| | - Korbinian Moeller
- LEAD Graduate School & Research Network, University of Tuebingen, Tuebingen, Germany.,Leibniz-Institut für Wissensmedien, Tuebingen, Germany.,Department of Psychology, University of Tuebingen, Tuebingen, Germany
| | - Elise Klein
- Leibniz-Institut für Wissensmedien, Tuebingen, Germany
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18
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19
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Siemann J, Petermann F. Evaluation of the Triple Code Model of numerical processing-Reviewing past neuroimaging and clinical findings. RESEARCH IN DEVELOPMENTAL DISABILITIES 2018; 72:106-117. [PMID: 29128782 DOI: 10.1016/j.ridd.2017.11.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2016] [Revised: 06/27/2017] [Accepted: 11/03/2017] [Indexed: 06/07/2023]
Abstract
UNLABELLED This review reconciles past findings on numerical processing with key assumptions of the most predominant model of arithmetic in the literature, the Triple Code Model (TCM). This is implemented by reporting diverse findings in the literature ranging from behavioral studies on basic arithmetic operations over neuroimaging studies on numerical processing to developmental studies concerned with arithmetic acquisition, with a special focus on developmental dyscalculia (DD). We evaluate whether these studies corroborate the model and discuss possible reasons for contradictory findings. A separate section is dedicated to the transfer of TCM to arithmetic development and to alternative accounts focusing on developmental questions of numerical processing. We conclude with recommendations for future directions of arithmetic research, raising questions that require answers in models of healthy as well as abnormal mathematical development. WHAT THIS PAPER ADDS This review assesses the leading model in the field of arithmetic processing (Triple Code Model) by presenting knowledge from interdisciplinary research. It assesses the observed contradictory findings and integrates the resulting opposing viewpoints. The focus is on the development of arithmetic expertise as well as abnormal mathematical development. The original aspect of this article is that it points to a gap in research on these topics and provides possible solutions for future models.
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Affiliation(s)
- Julia Siemann
- Centre for Clinical Psychology and Rehabilitation (CCPR), University of Bremen, Bremen, Germany.
| | - Franz Petermann
- Centre for Clinical Psychology and Rehabilitation (CCPR), University of Bremen, Bremen, Germany.
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20
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Nelson JM, McKinley RA, McIntire LK, Goodyear C, Walters C. Augmenting Visual Search Performance With Transcranial Direct Current Stimulation (tDCS). MILITARY PSYCHOLOGY 2017. [DOI: 10.1037/mil0000085] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
| | - R. Andy McKinley
- 711th HPW, Applied Neuroscience Branch, U.S. Air Force Research Laboratory, Wright-Patterson AFB, Ohio
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21
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Naaman R, Goldfarb L. The Influence of Gain and Loss on Arithmetic Performance. Front Psychol 2017; 8:2150. [PMID: 29312037 PMCID: PMC5733073 DOI: 10.3389/fpsyg.2017.02150] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 11/27/2017] [Indexed: 11/13/2022] Open
Abstract
Gain and loss modulation of different aspects of executive functions (EF) has been studied under changing conditions. However, the nature of this effect varies in different EF tasks, as both gain and loss were found to improve performance in specific EF tasks while hindering performance in others. The current study examines the influence of gain and loss stimuli on arithmetic performance. Since arithmetic processes have been found to rely heavily on EF, the current study addresses the question of "whether" and "in what direction" those stimuli might affect arithmetic performance. In three experiments, participants preformed an arithmetic equation judgment task, while gain and loss conditions were added in each trial in the form of a line drawn face representing either monetary gain, loss, or neither. In Experiment 1, the arithmetic task included carry and non-carry equations representing different arithmetic complexity levels. In Experiment 2, two and three addend equations were used, and in Experiment 3, the proportions of correct and incorrect equations differed. Results of all experiments demonstrated faster RT in the arithmetic task after gain stimuli when compared to the loss stimuli. Our results further extend our understanding regarding the nature of the relationship between gain and loss situations and arithmetic performance and further emphasize the conditions under which arithmetic performance can be improved or hindered.
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Affiliation(s)
| | - Liat Goldfarb
- Edmond J. Safra Brain Research Center for the Study of Learning Disabilities, Department of Learning Disabilities, University of Haifa, Haifa, Israel
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22
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Bikson M, Paneri B, Mourdoukoutas A, Esmaeilpour Z, Badran BW, Azzam R, Adair D, Datta A, Fang XH, Wingeier B, Chao D, Alonso-Alonso M, Lee K, Knotkova H, Woods AJ, Hagedorn D, Jeffery D, Giordano J, Tyler WJ. Limited output transcranial electrical stimulation (LOTES-2017): Engineering principles, regulatory statutes, and industry standards for wellness, over-the-counter, or prescription devices with low risk. Brain Stimul 2017; 11:134-157. [PMID: 29122535 DOI: 10.1016/j.brs.2017.10.012] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 09/16/2017] [Accepted: 10/15/2017] [Indexed: 01/17/2023] Open
Abstract
We present device standards for low-power non-invasive electrical brain stimulation devices classified as limited output transcranial electrical stimulation (tES). Emerging applications of limited output tES to modulate brain function span techniques to stimulate brain or nerve structures, including transcranial direct current stimulation (tDCS), transcranial alternating current stimulation (tACS), and transcranial pulsed current stimulation (tPCS), have engendered discussion on how access to technology should be regulated. In regards to legal regulations and manufacturing standards for comparable technologies, a comprehensive framework already exists, including quality systems (QS), risk management, and (inter)national electrotechnical standards (IEC). In Part 1, relevant statutes are described for medical and wellness application. While agencies overseeing medical devices have broad jurisdiction, enforcement typically focuses on those devices with medical claims or posing significant risk. Consumer protections regarding responsible marketing and manufacture apply regardless. In Part 2 of this paper, we classify the electrical output performance of devices cleared by the United States Food and Drug Administration (FDA) including over-the-counter (OTC) and prescription electrostimulation devices, devices available for therapeutic or cosmetic purposes, and devices indicated for stimulation of the body or head. Examples include iontophoresis devices, powered muscle stimulators (PMS), cranial electrotherapy stimulation (CES), and transcutaneous electrical nerve stimulation (TENS) devices. Spanning over 13 FDA product codes, more than 1200 electrical stimulators have been cleared for marketing since 1977. The output characteristics of conventional tDCS, tACS, and tPCS techniques are well below those of most FDA cleared devices, including devices that are available OTC and those intended for stimulation on the head. This engineering analysis demonstrates that with regard to output performance and standing regulation, the availability of tDCS, tACS, or tPCS to the public would not introduce risk, provided such devices are responsibly manufactured and legally marketed. In Part 3, we develop voluntary manufacturer guidance for limited output tES that is aligned with current regulatory standards. Based on established medical engineering and scientific principles, we outline a robust and transparent technical framework for ensuring limited output tES devices are designed to minimize risks, while also supporting access and innovation. Alongside applicable medical and government activities, this voluntary industry standard (LOTES-2017) further serves an important role in supporting informed decisions by the public.
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Affiliation(s)
- Marom Bikson
- The City College of New York, Department of Biomedical Engineering, New York, NY 10031, USA.
| | - Bhaskar Paneri
- The City College of New York, Department of Biomedical Engineering, New York, NY 10031, USA
| | - Andoni Mourdoukoutas
- The City College of New York, Department of Biomedical Engineering, New York, NY 10031, USA
| | - Zeinab Esmaeilpour
- The City College of New York, Department of Biomedical Engineering, New York, NY 10031, USA
| | - Bashar W Badran
- U.S. Army Research Laboratory, Aberdeen Proving Ground, MD, USA; Department of Psychology, University of New Mexico, Albuquerque, NM, USA
| | | | - Devin Adair
- The City College of New York, Department of Biomedical Engineering, New York, NY 10031, USA
| | | | - Xiao Hui Fang
- The City College of New York, Department of Biomedical Engineering, New York, NY 10031, USA
| | | | - Daniel Chao
- Halo Neuroscience Inc., San Francisco, CA 94103, USA
| | - Miguel Alonso-Alonso
- Harvard Medical School, Berenson-Allen Center for Noninvasive Brain Stimulation, Division of Cognitive Neurology, Boston, MA, USA
| | - Kiwon Lee
- Ybrain Inc., Sampyeong-dong, Seongnam-si, South Korea
| | - Helena Knotkova
- MJHS Institute for Innovation in Palliative Care, New York, NY, USA; Department of Family and Social Medicine, Albert Einstein College of Medicine, The Bronx, NY, USA
| | - Adam J Woods
- Center for Cognitive Aging and Memory, McKnight Brain Institute, Department of Clinical and Health Psychology, University of Florida, USA
| | | | | | - James Giordano
- Department of Neurology and Neuroethics Studies Program, Pellegrino Center for Clinical Bioethics, Georgetown University Medical Center, Washington, DC, USA
| | - William J Tyler
- Arizona State University, School of Biological and Health Systems Engineering, Tempe, AZ 85287, USA
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23
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Lavazza A. Can Neuromodulation also Enhance Social Inequality? Some Possible Indirect Interventions of the State. Front Hum Neurosci 2017; 11:113. [PMID: 28326031 PMCID: PMC5339233 DOI: 10.3389/fnhum.2017.00113] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 02/22/2017] [Indexed: 12/21/2022] Open
Abstract
There is evidence that noninvasive brain stimulation (NIBS), and especially transcranial direct current stimulation (tDCS), can improve some cognitive functions, at least temporarily. However, as the improvement only applies to some “lucky” people, it may raise ethical, social and legal issues related to fairness in selective contexts (exams, competitions, job interviews). In this regard, an important element tends to be overlooked: the variability in individual response to tDCS in particular. If intensive study or practice and massive doses of chemical enhancers can have slightly different effects over different people, tDCS can sometimes be completely ineffective. The variability in individual response, if tDCS were widely used, could add to the already present natural inequalities between people, or even create new ones, leaving some in a disadvantaged condition. The discussion of the various ethical, social and legal consequences of different individual responses to tDCS might also address a potential indirect intervention by the State. In fact, if NIBS were to be widespread in competitive contexts, those who do not benefit from tDCS would be disadvantaged compared to those able to enhance their skills thanks to neuromodulation technologies. The most disadvantaged people for their lower response to tDCS could then acquire the right to receive and use free and safe cognitive enhancing drugs or other forms of bettering cognitive skills and functions, so as to reduce the gap between them and those who respond well to tDCS, in the light of the principle of equal opportunity.
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Affiliation(s)
- Andrea Lavazza
- Department of Neuroethics, Centro Universitario Internazionale Arezzo, Italy
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25
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Schroeder PA, Dresler T, Bahnmueller J, Artemenko C, Cohen Kadosh R, Nuerk HC. Cognitive Enhancement of Numerical and Arithmetic Capabilities: a Mini-Review of Available Transcranial Electric Stimulation Studies. JOURNAL OF COGNITIVE ENHANCEMENT 2017. [DOI: 10.1007/s41465-016-0006-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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26
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Rosen DS, Erickson B, Kim YE, Mirman D, Hamilton RH, Kounios J. Anodal tDCS to Right Dorsolateral Prefrontal Cortex Facilitates Performance for Novice Jazz Improvisers but Hinders Experts. Front Hum Neurosci 2016; 10:579. [PMID: 27899889 PMCID: PMC5110534 DOI: 10.3389/fnhum.2016.00579] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 11/01/2016] [Indexed: 11/29/2022] Open
Abstract
Research on creative cognition reveals a fundamental disagreement about the nature of creative thought, specifically, whether it is primarily based on automatic, associative (Type-1) or executive, controlled (Type-2) processes. We hypothesized that Type-1 and Type-2 processes make differential contributions to creative production that depend on domain expertise. We tested this hypothesis with jazz pianists whose expertise was indexed by the number of public performances given. Previous fMRI studies of musical improvisation have reported that domain expertise is characterized by deactivation of the right-dorsolateral prefrontal cortex (r-DLPFC), a brain area associated with Type-2 executive processing. We used anodal, cathodal, and sham transcranial direct current stimulation (tDCS) applied over r-DLPFC with the reference electrode on the contralateral mastoid (1.5 mA for 15 min, except for sham) to modulate the quality of the pianists' performances while they improvised over chords with drum and bass accompaniment. Jazz experts rated each improvisation for creativity, esthetic appeal, and technical proficiency. There was no main effect of anodal or cathodal stimulation on ratings compared to sham; however, a significant interaction between anodal tDCS and expertise emerged such that stimulation benefitted musicians with less experience but hindered those with more experience. We interpret these results as evidence for a dual-process model of creativity in which novices and experts differentially engage Type-1 and Type-2 processes during creative production.
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Affiliation(s)
- David S Rosen
- Creativity Research Laboratory, Department of Psychology, Drexel University Philadelphia, PA, USA
| | - Brian Erickson
- Creativity Research Laboratory, Department of Psychology, Drexel University Philadelphia, PA, USA
| | - Youngmoo E Kim
- Music and Entertainment Technology Laboratory, Department of Electrical and Computer Engineering, Drexel University Philadelphia, PA, USA
| | - Daniel Mirman
- Language and Cognitive Dynamics Laboratory, Department of Psychology, University of Alabama at Birmingham Birmingham, AL, USA
| | - Roy H Hamilton
- Laboratory for Cognition and Neural Stimulation, Perelman School of Medicine, University of Pennsylvania Philadelphia, PA, USA
| | - John Kounios
- Creativity Research Laboratory, Department of Psychology, Drexel University Philadelphia, PA, USA
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27
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Brezis N, Bronfman ZZ, Jacoby N, Lavidor M, Usher M. Transcranial Direct Current Stimulation over the Parietal Cortex Improves Approximate Numerical Averaging. J Cogn Neurosci 2016; 28:1700-1713. [DOI: 10.1162/jocn_a_00991] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Abstract
The parietal cortex has been implicated in a variety of numerosity and numerical cognition tasks and was proposed to encompass dedicated neural populations that are tuned for analogue magnitudes as well as for symbolic numerals. Nonetheless, it remains unknown whether the parietal cortex plays a role in approximate numerical averaging (rapid, yet coarse computation of numbers' mean)—a process that is fundamental to preference formation and decision-making. To causally investigate the role of the parietal cortex in numerical averaging, we have conducted a transcranial direct current stimulation (tDCS) study, in which participants were presented with rapid sequences of numbers and asked to convey their intuitive estimation of each sequence's average. During the task, the participants underwent anodal (excitatory) tDCS (or sham), applied either on a parietal or a frontal region. We found that, although participants exhibit above-chance accuracy in estimating the average of numerical sequences, they did so with higher precision under parietal stimulation. In a second experiment, we have replicated this finding and confirmed that the effect is number-specific rather than domain-general or attentional. We present a neurocomputational model postulating population-coding underlying rapid numerical averaging to account for our findings. According to this model, stimulation of the parietal cortex elevates neural activity in number-tuned dedicated detectors, leading to increase in the system's signal-to-noise level and thus resulting in more precise estimations.
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Schroeder PA, Pfister R, Kunde W, Nuerk HC, Plewnia C. Counteracting Implicit Conflicts by Electrical Inhibition of the Prefrontal Cortex. J Cogn Neurosci 2016; 28:1737-1748. [DOI: 10.1162/jocn_a_01001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Abstract
Cognitive conflicts and distractions by task-irrelevant information often counteract effective and goal-directed behaviors. In some cases, conflicting information can even emerge implicitly, without an overt distractor, by the automatic activation of mental representations. For instance, during number processing, magnitude information automatically elicits spatial associations resembling a mental number line. This spatial–numerical association of response codes (SNARC) effect can modulate cognitive-behavioral performance but is also highly flexible and context-dependent, which points toward a critical involvement of working memory functions. Transcranial direct current stimulation to the PFC, in turn, has been effective in modulating working memory-related cognitive performance. In a series of experiments, we here demonstrate that decreasing activity of the left PFC by cathodal transcranial direct current stimulation consistently and specifically eliminates implicit cognitive conflicts based on the SNARC effect, but explicit conflicts based on visuospatial distraction remain unaffected. This dissociation is polarity-specific and appears unrelated to functional magnitude processing as classified by regular numerical distance effects. These data demonstrate a causal involvement of the left PFC in implicit cognitive conflicts based on the automatic activation of spatial–numerical processing. Corroborating the critical interaction of brain stimulation and neurocognitive functions, our findings suggest that distraction from goal-directed behavior by automatic activation of implicit, task-irrelevant information can be blocked by the inhibition of prefrontal activity.
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Affiliation(s)
| | | | | | - Hans-Christoph Nuerk
- 1University of Tübingen
- 3Knowledge Media Research Center IWM_KMRC, Tübingen, Germany
| | - Christian Plewnia
- 1University of Tübingen
- 4Werner Reichardt Centre for Integrative Neuroscience (CIN), Tübingen, Germany
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Hauser TU, Rütsche B, Wurmitzer K, Brem S, Ruff CC, Grabner RH. Neurocognitive Effects of Transcranial Direct Current Stimulation in Arithmetic Learning and Performance: A Simultaneous tDCS-fMRI Study. Brain Stimul 2016; 9:850-858. [PMID: 27522169 DOI: 10.1016/j.brs.2016.07.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 06/15/2016] [Accepted: 07/18/2016] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND A small but increasing number of studies suggest that non-invasive brain stimulation by means of transcranial direct current stimulation (tDCS) can modulate arithmetic processes that are essential for higher-order mathematical skills and that are impaired in dyscalculic individuals. However, little is known about the neural mechanisms underlying such stimulation effects, and whether they are specific to cognitive processes involved in different arithmetic tasks. METHODS We addressed these questions by applying tDCS during simultaneous functional magnetic resonance imaging (fMRI) while participants were solving two types of complex subtraction problems: repeated problems, relying on arithmetic fact learning and problem-solving by fact retrieval, and novel problems, requiring calculation procedures. Twenty participants receiving left parietal anodal plus right frontal cathodal stimulation were compared with 20 participants in a sham condition. RESULTS We found a strong cognitive and neural dissociation between repeated and novel problems. Repeated problems were solved more accurately and elicited increased activity in the bilateral angular gyri and medial plus lateral prefrontal cortices. Solving novel problems, in contrast, was accompanied by stronger activation in the bilateral intraparietal sulci and the dorsomedial prefrontal cortex. Most importantly, tDCS decreased the activation of the right inferior frontal cortex while solving novel (compared to repeated) problems, suggesting that the cathodal stimulation rendered this region unable to respond to the task-specific cognitive demand. CONCLUSIONS The present study revealed that tDCS during arithmetic problem-solving can modulate the neural activity in proximity to the electrodes specifically when the current demands lead to an engagement of this area.
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Affiliation(s)
- Tobias U Hauser
- Wellcome Trust Centre for Neuroimaging, University College London, 12 Queen Square, London WC1N 3BG, UK; Max Planck UCL Centre for Computational Psychiatry and Ageing Research, 10-12 Russel Square, London WC1B 5EH, UK.
| | - Bruno Rütsche
- Institute for Behavioral Sciences, ETH Zurich, Clausiusstrasse 59, 8092 Zürich, Switzerland
| | - Karoline Wurmitzer
- Institute for Behavioral Sciences, ETH Zurich, Clausiusstrasse 59, 8092 Zürich, Switzerland
| | - Silvia Brem
- Department of Child and Adolescent Psychiatry and Psychotherapy, Psychiatric Hospital, University of Zurich, 8032 Zürich, Switzerland; Neuroscience Center Zurich, University of Zurich and ETH Zurich, Switzerland
| | - Christian C Ruff
- Neuroscience Center Zurich, University of Zurich and ETH Zurich, Switzerland; Laboratory for Social and Neural Systems Research (SNS-Lab), Department of Economics, University of Zurich, Bluemlisalpstrasse 10, 8006 Zürich, Switzerland
| | - Roland H Grabner
- Institute of Psychology, University of Graz, Universitaetsplatz 2, 8010 Graz, Austria
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Choe J, Coffman BA, Bergstedt DT, Ziegler MD, Phillips ME. Transcranial Direct Current Stimulation Modulates Neuronal Activity and Learning in Pilot Training. Front Hum Neurosci 2016; 10:34. [PMID: 26903841 PMCID: PMC4746294 DOI: 10.3389/fnhum.2016.00034] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 01/19/2016] [Indexed: 01/22/2023] Open
Abstract
Skill acquisition requires distributed learning both within (online) and across (offline) days to consolidate experiences into newly learned abilities. In particular, piloting an aircraft requires skills developed from extensive training and practice. Here, we tested the hypothesis that transcranial direct current stimulation (tDCS) can modulate neuronal function to improve skill learning and performance during flight simulator training of aircraft landing procedures. Thirty-two right-handed participants consented to participate in four consecutive daily sessions of flight simulation training and received sham or anodal high-definition-tDCS to the right dorsolateral prefrontal cortex (DLPFC) or left motor cortex (M1) in a randomized, double-blind experiment. Continuous electroencephalography (EEG) and functional near infrared spectroscopy (fNIRS) were collected during flight simulation, n-back working memory, and resting-state assessments. tDCS of the right DLPFC increased midline-frontal theta-band activity in flight and n-back working memory training, confirming tDCS-related modulation of brain processes involved in executive function. This modulation corresponded to a significantly different online and offline learning rates for working memory accuracy and decreased inter-subject behavioral variability in flight and n-back tasks in the DLPFC stimulation group. Additionally, tDCS of left M1 increased parietal alpha power during flight tasks and tDCS to the right DLPFC increased midline frontal theta-band power during n-back and flight tasks. These results demonstrate a modulation of group variance in skill acquisition through an increasing in learned skill consistency in cognitive and real-world tasks with tDCS. Further, tDCS performance improvements corresponded to changes in electrophysiological and blood-oxygenation activity of the DLPFC and motor cortices, providing a stronger link between modulated neuronal function and behavior.
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Affiliation(s)
| | - Brian A Coffman
- HRL Laboratories LLCMalibu, CA, USA; Department of Psychiatry, The University of PittsburghPittsburgh, PA, USA; Psychology Clinical Neuroscience Center, The University of New MexicoAlbuquerque, NM, USA
| | - Dylan T Bergstedt
- HRL Laboratories LLCMalibu, CA, USA; Department of Sports Medicine, Pepperdine UniversityMalibu, CA, USA
| | - Matthias D Ziegler
- HRL Laboratories LLCMalibu, CA, USA; Advanced Technologies Laboratories, Lockheed MartinArlington, VA, USA
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Houser R, Thoma S, Fonseca D, O’Conner E, Stanton M. Enhancing statistical calculation with transcranial direct current stimulation (tDCS) to the left intra-parietal sulcus (IPS). Trends Neurosci Educ 2015. [DOI: 10.1016/j.tine.2015.07.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Li LM, Leech R, Scott G, Malhotra P, Seemungal B, Sharp DJ. The effect of oppositional parietal transcranial direct current stimulation on lateralized brain functions. Eur J Neurosci 2015; 42:2904-14. [PMID: 26414683 PMCID: PMC4737321 DOI: 10.1111/ejn.13086] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 09/15/2015] [Accepted: 09/23/2015] [Indexed: 11/30/2022]
Abstract
Cognitive functions such as numerical processing and spatial attention show varying degrees of lateralization. Transcranial direct current stimulation (tDCS) can be used to investigate how modulating cortical excitability affects performance of these tasks. This study investigated the effect of bi-parietal tDCS on numerical processing, spatial and sustained attention. It was hypothesized that tDCS would have distinct effects on these tasks because of varying lateralization (numerical processing left, spatial attention right) and that these effects are partly mediated by modulation of sustained attention. A single-blinded, crossover, sham-controlled study was performed. Eighteen healthy right-handed participants performed cognitive tasks during three sessions of oppositional parietal tDCS stimulation: sham; right anodal with left cathodal (RA/LC); and right cathodal with left anodal (RC/LA). Participants performed a number comparison task, a modified Posner task, a choice reaction task (CRT) and the rapid visual processing task (RVP). RA/LC tDCS impaired number comparison performance compared with sham, with slower responses to numerically close numbers pairs. RA/LC and RC/LA tDCS had distinct effects on CRT performance, specifically affecting vigilance level during the final block of the task. No effect of stimulation on the Posner task or RVP was found. It was demonstrated that oppositional parietal tDCS affected both numerical performance and vigilance level in a polarity-dependent manner. The effect of tDCS on numerical processing may partly be due to attentional effects. The behavioural effects of tDCS were specifically observed under high task demands, demonstrating the consequences of an interaction between stimulation type and cognitive load.
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Affiliation(s)
- Lucia M Li
- Computational, Cognitive and Clinical Neuroimaging Laboratory (C3NL), Division of Brain Sciences, Department of Medicine, Imperial College London, C3NL 3rd Floor Burlington Danes Building, Du Cane Road, Fulham, London, W12 0NN, UK
| | - Rob Leech
- Computational, Cognitive and Clinical Neuroimaging Laboratory (C3NL), Division of Brain Sciences, Department of Medicine, Imperial College London, C3NL 3rd Floor Burlington Danes Building, Du Cane Road, Fulham, London, W12 0NN, UK
| | - Gregory Scott
- Computational, Cognitive and Clinical Neuroimaging Laboratory (C3NL), Division of Brain Sciences, Department of Medicine, Imperial College London, C3NL 3rd Floor Burlington Danes Building, Du Cane Road, Fulham, London, W12 0NN, UK
| | - Paresh Malhotra
- Centre for Restorative Neuroscience, Imperial College London, London, UK
| | - Barry Seemungal
- Neuro-Otology Unit, Division of Brain Sciences, Imperial College London, London, UK
| | - David J Sharp
- Computational, Cognitive and Clinical Neuroimaging Laboratory (C3NL), Division of Brain Sciences, Department of Medicine, Imperial College London, C3NL 3rd Floor Burlington Danes Building, Du Cane Road, Fulham, London, W12 0NN, UK
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Hoy KE, Bailey N, Michael M, Fitzgibbon B, Rogasch NC, Saeki T, Fitzgerald PB. Enhancement of Working Memory and Task-Related Oscillatory Activity Following Intermittent Theta Burst Stimulation in Healthy Controls. Cereb Cortex 2015; 26:4563-4573. [DOI: 10.1093/cercor/bhv193] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
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Abstract
This study explores the relationship between the split effect and the use of exact versus approximate strategies in complex-subtraction calculations. One-hundred and two-digit subtraction problems were presented, with half of them being small-split problems with answers ±2 or ±5 from 50 and the other half being large-split problems with answers ±10 or ±15 from 50. Participants were asked to indicate whether the answer was less than 50. The measures were speed and accuracy of task performance, and high temporal resolution event-related potentials. Behavioral data showed that participants had a longer time requirement and a lower accuracy in solving small-split problems than in solving large-split problems. Event-related potential data show that, comparatively, the small-split problems led to more-negative, more-lateralized waves as early as 250 ms at frontal, frontocentral, and central sites. Our results, which are in agreement with previous studies, suggest that the participants used exact strategies to solve small-split problems and approximate strategies to solve large-split problems when performing complex subtractions. These results further our understanding of the brain mechanisms underlying the relationship between small/large-split effects and exact/approximate strategies in this task domain.
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Grabner RH, Rütsche B, Ruff CC, Hauser TU. Transcranial direct current stimulation of the posterior parietal cortex modulates arithmetic learning. Eur J Neurosci 2015; 42:1667-74. [DOI: 10.1111/ejn.12947] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 05/06/2015] [Accepted: 05/11/2015] [Indexed: 01/07/2023]
Affiliation(s)
- Roland H. Grabner
- Department of Psychology; University of Graz; Maiffredygasse 12b A-8010 Graz Austria
- Department of Psychology; University of Göttingen; Göttingen Germany
| | - Bruno Rütsche
- Institute for Behavioral Sciences; ETH Zurich; Zurich Switzerland
| | - Christian C. Ruff
- Laboratory for Social and Neural Systems Research (SNS-Lab); Department of Economics; University of Zurich; Zurich Switzerland
| | - Tobias U. Hauser
- Wellcome Trust Centre for Neuroimaging; Institute of Neurology; University College London; London UK
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Decker SL, Roberts AM. SPECIFIC COGNITIVE PREDICTORS OF EARLY MATH PROBLEM SOLVING. PSYCHOLOGY IN THE SCHOOLS 2015. [DOI: 10.1002/pits.21837] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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When problem size matters: differential effects of brain stimulation on arithmetic problem solving and neural oscillations. PLoS One 2015; 10:e0120665. [PMID: 25789486 PMCID: PMC4366159 DOI: 10.1371/journal.pone.0120665] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 02/05/2015] [Indexed: 01/28/2023] Open
Abstract
The problem size effect is a well-established finding in arithmetic problem solving and is characterized by worse performance in problems with larger compared to smaller operand size. Solving small and large arithmetic problems has also been shown to involve different cognitive processes and distinct electroencephalography (EEG) oscillations over the left posterior parietal cortex (LPPC). In this study, we aimed to provide further evidence for these dissociations by using transcranial direct current stimulation (tDCS). Participants underwent anodal (30min, 1.5 mA, LPPC) and sham tDCS. After the stimulation, we recorded their neural activity using EEG while the participants solved small and large arithmetic problems. We found that the tDCS effects on performance and oscillatory activity critically depended on the problem size. While anodal tDCS improved response latencies in large arithmetic problems, it decreased solution rates in small arithmetic problems. Likewise, the lower-alpha desynchronization in large problems increased, whereas the theta synchronization in small problems decreased. These findings reveal that the LPPC is differentially involved in solving small and large arithmetic problems and demonstrate that the effects of brain stimulation strikingly differ depending on the involved neuro-cognitive processes.
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Artemenko C, Moeller K, Huber S, Klein E. Differential influences of unilateral tDCS over the intraparietal cortex on numerical cognition. Front Hum Neurosci 2015; 9:110. [PMID: 25798099 PMCID: PMC4350389 DOI: 10.3389/fnhum.2015.00110] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 02/13/2015] [Indexed: 11/13/2022] Open
Abstract
Recent neuro-imaging research identified the bilateral intraparietal sulcus (IPS) to be a key area associated with number processing. However, causal structure-function relationships are hard to evaluate from neuro-imaging techniques such as fMRI. Nevertheless, brain stimulation methods like transcranial direct current stimulation (tDCS) allow for investigating the functional relevance of the IPS for number processing. Following up on a study using bilateral bi-cephalic tDCS over the IPS, the current study aimed at evaluating the differential lateralized functional contributions of the left and right IPS to number processing using unilateral bi-cephalic tDCS over either the left or right IPS. Results indicated a right lateralization for the processing of the place-value structure of the Arabic number system. Importantly, the processing of number magnitude information was not affected by unilateral IPS corroborating the assumption that number magnitude is processed in the bilateral IPS. Taken together, these data suggest that even though number magnitude is represented bilaterally, the left and right IPS seem to contribute differentially to numerical cognition with respect to the processing of specific other aspects of numerical information.
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Affiliation(s)
- Christina Artemenko
- LEAD Graduate School, Eberhardt Karls University of Tuebingen Tuebingen, Germany
| | - Korbinian Moeller
- LEAD Graduate School, Eberhardt Karls University of Tuebingen Tuebingen, Germany ; Knowledge Media Research Center Tuebingen, Germany
| | - Stefan Huber
- Knowledge Media Research Center Tuebingen, Germany
| | - Elise Klein
- Knowledge Media Research Center Tuebingen, Germany
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Quantitative Review Finds No Evidence of Cognitive Effects in Healthy Populations From Single-session Transcranial Direct Current Stimulation (tDCS). Brain Stimul 2015; 8:535-50. [PMID: 25701175 DOI: 10.1016/j.brs.2015.01.400] [Citation(s) in RCA: 401] [Impact Index Per Article: 44.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Revised: 01/09/2015] [Accepted: 01/12/2015] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Over the last 15-years, transcranial direct current stimulation (tDCS), a relatively novel form of neuromodulation, has seen a surge of popularity in both clinical and academic settings. Despite numerous claims suggesting that a single session of tDCS can modulate cognition in healthy adult populations (especially working memory and language production), the paradigms utilized and results reported in the literature are extremely variable. To address this, we conduct the largest quantitative review of the cognitive data to date. METHODS Single-session tDCS data in healthy adults (18-50) from every cognitive outcome measure reported by at least two different research groups in the literature was collected. Outcome measures were divided into 4 broad categories: executive function, language, memory, and miscellaneous. To account for the paradigmatic variability in the literature, we undertook a three-tier analysis system; each with less-stringent inclusion criteria than the prior. Standard mean difference values with 95% CIs were generated for included studies and pooled for each analysis. RESULTS Of the 59 analyses conducted, tDCS was found to not have a significant effect on any - regardless of inclusion laxity. This includes no effect on any working memory outcome or language production task. CONCLUSION Our quantitative review does not support the idea that tDCS generates a reliable effect on cognition in healthy adults. Reasons for and limitations of this finding are discussed. This work raises important questions regarding the efficacy of tDCS, state-dependency effects, and future directions for this tool in cognitive research.
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Cohen Kadosh R. Modulating and enhancing cognition using brain stimulation: Science and fiction. JOURNAL OF COGNITIVE PSYCHOLOGY 2015. [DOI: 10.1080/20445911.2014.996569] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Pergolizzi D, Chua EF. Transcranial direct current stimulation (tDCS) of the parietal cortex leads to increased false recognition. Neuropsychologia 2015; 66:88-98. [DOI: 10.1016/j.neuropsychologia.2014.11.012] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Revised: 11/11/2014] [Accepted: 11/13/2014] [Indexed: 01/28/2023]
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Scheldrup M, Greenwood PM, McKendrick R, Strohl J, Bikson M, Alam M, McKinley RA, Parasuraman R. Transcranial direct current stimulation facilitates cognitive multi-task performance differentially depending on anode location and subtask. Front Hum Neurosci 2014; 8:665. [PMID: 25249958 PMCID: PMC4157612 DOI: 10.3389/fnhum.2014.00665] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Accepted: 08/11/2014] [Indexed: 11/13/2022] Open
Abstract
There is a need to facilitate acquisition of real world cognitive multi-tasks that require long periods of training (e.g., air traffic control, intelligence analysis, medicine). Non-invasive brain stimulation—specifically transcranial Direct Current Stimulation (tDCS)—has promise as a method to speed multi-task training. We hypothesized that during acquisition of the complex multi-task Space Fortress, subtasks that require focused attention on ship control would benefit from tDCS aimed at the dorsal attention network while subtasks that require redirection of attention would benefit from tDCS aimed at the right hemisphere ventral attention network. We compared effects of 30 min prefrontal and parietal stimulation to right and left hemispheres on subtask performance during the first 45 min of training. The strongest effects both overall and for ship flying (control and velocity subtasks) were seen with a right parietal (C4, reference to left shoulder) montage, shown by modeling to induce an electric field that includes nodes in both dorsal and ventral attention networks. This is consistent with the re-orienting hypothesis that the ventral attention network is activated along with the dorsal attention network if a new, task-relevant event occurs while visuospatial attention is focused (Corbetta et al., 2008). No effects were seen with anodes over sites that stimulated only dorsal (C3) or only ventral (F10) attention networks. The speed subtask (update memory for symbols) benefited from an F9 anode over left prefrontal cortex. These results argue for development of tDCS as a training aid in real world settings where multi-tasking is critical.
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Affiliation(s)
- Melissa Scheldrup
- Arch Lab, Department of Psychology, George Mason University Fairfax, VA, USA
| | - Pamela M Greenwood
- Arch Lab, Department of Psychology, George Mason University Fairfax, VA, USA
| | - Ryan McKendrick
- Arch Lab, Department of Psychology, George Mason University Fairfax, VA, USA
| | - Jon Strohl
- Arch Lab, Department of Psychology, George Mason University Fairfax, VA, USA
| | - Marom Bikson
- Neural Engineering Group, Department of Biomedical Engineering, The City College of New York of CUNY New York, NY, USA
| | - Mahtab Alam
- Neural Engineering Group, Department of Biomedical Engineering, The City College of New York of CUNY New York, NY, USA
| | - R Andy McKinley
- 711th HPW, Warfighter Interfaces Division, Applied Neuroscience Branch, WPAFB Wright-Patterson AFB, OH, USA
| | - Raja Parasuraman
- Arch Lab, Department of Psychology, George Mason University Fairfax, VA, USA
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Transcranial electrical brain stimulation modulates neuronal tuning curves in perception of numerosity and duration. Neuroimage 2014; 102 Pt 2:451-7. [PMID: 25130301 PMCID: PMC4229383 DOI: 10.1016/j.neuroimage.2014.08.016] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2014] [Revised: 07/14/2014] [Accepted: 08/08/2014] [Indexed: 11/20/2022] Open
Abstract
Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation method with many putative applications and reported to effectively modulate behaviour. However, its effects have yet to be considered at a computational level. To address this we modelled the tuning curves underlying the behavioural effects of stimulation in a perceptual task. Participants judged which of the two serially presented images contained more items (numerosity judgement task) or was presented longer (duration judgement task). During presentation of the second image their posterior parietal cortices (PPCs) were stimulated bilaterally with opposite polarities for 1.6 s. We also examined the impact of three stimulation conditions on behaviour: anodal right-PPC and cathodal left-PPC (rA-lC), reverse order (lA-rC) and no-stimulation condition. Behavioural results showed that participants were more accurate in numerosity and duration judgement tasks when they were stimulated with lA-rC and rA-lC stimulation conditions respectively. Simultaneously, a decrease in performance on numerosity and duration judgement tasks was observed when the stimulation condition favoured the other task. Thus, our results revealed a double-dissociation of laterality and task. Importantly, we were able to model the effects of stimulation on behaviour. Our computational modelling showed that participants' superior performance was attributable to a narrower tuning curve — smaller standard deviation of detection noise. We believe that this approach may prove useful in understanding the impact of brain stimulation on other cognitive domains. Behavioural effects of transcranial electrical stimulation were modelled. Computational modelling was based on tuning curves found in human and primates. Superior performance was attributable to a narrower tuning curve and vice versa. Results revealed a double-dissociation of laterality of stimulation and task. While stimulation improved performance in one task, it impaired performance in another.
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Han CH, Song H, Kang YG, Kim BM, Im CH. Hemodynamic responses in rat brain during transcranial direct current stimulation: a functional near-infrared spectroscopy study. BIOMEDICAL OPTICS EXPRESS 2014; 5:1812-21. [PMID: 24940542 PMCID: PMC4052913 DOI: 10.1364/boe.5.001812] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Revised: 04/18/2014] [Accepted: 04/21/2014] [Indexed: 05/22/2023]
Abstract
In the present study, we monitored hemodynamic responses in rat brains during transcranial direct current stimulation (tDCS) using functional near-infrared spectroscopy (fNIRS). Seven rats received transcranial anodal stimulation with 200 μA direct current (DC) on their right barrel cortex for 10 min. The concentration changes of oxygenated hemoglobin (oxy-Hb) were continuously monitored during stimulation (10 min) and after stimulation (20 min). The trend of hemodynamic response changes was modeled using linear regression, and the relationship between incremental and decremental rates of oxy-Hb was investigated by correlation analysis. Our results showed that the oxy-Hb concentration was almost linearly increased and decreased during and after stimulation, respectively. In addition, a significant negative correlation (p < 0.05) was found between the rate of increase of oxy-Hb during stimulation and the rate of decrease of oxy-Hb after stimulation, indicating that the recovery time after tDCS may not depend on the total amount of hemodynamic changes in the stimulated brain area. Our results also demonstrated considerable individual variability in the rate of change of hemodynamic responses even with the same direct current dose to identical brain regions. This suggests that individual differences in tDCS after-effects may originate from intrinsic differences in the speed of DC stimulation "uptake" rather than differences in the total capacity of DC uptake, and thus the stimulation parameters may need to be customized for each individual in order to maximize tDCS after-effects.
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Affiliation(s)
- Chang-Hee Han
- Department of Biomedical Engineering, Hanyang University, Wangsimni-ro, Seongdong-gu, Seoul, 133-791, South Korea
- contributed equally
| | - Hyuna Song
- Department of Biomedical Engineering, Korea University, Jeongneung 3-dong, Seongbuk-ku, Seoul, 136-703, South Korea
- contributed equally
| | - Yong-Guk Kang
- Department of Biomedical Engineering, Korea University, Jeongneung 3-dong, Seongbuk-ku, Seoul, 136-703, South Korea
| | - Beop-Min Kim
- Department of Biomedical Engineering, Korea University, Jeongneung 3-dong, Seongbuk-ku, Seoul, 136-703, South Korea
| | - Chang-Hwan Im
- Department of Biomedical Engineering, Hanyang University, Wangsimni-ro, Seongdong-gu, Seoul, 133-791, South Korea
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Iuculano T, Cohen Kadosh R. Preliminary evidence for performance enhancement following parietal lobe stimulation in Developmental Dyscalculia. Front Hum Neurosci 2014; 8:38. [PMID: 24570659 PMCID: PMC3916771 DOI: 10.3389/fnhum.2014.00038] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 01/17/2014] [Indexed: 01/29/2023] Open
Abstract
Nearly 7% of the population exhibit difficulties in dealing with numbers and performing arithmetic, a condition named Developmental Dyscalculia (DD), which significantly affects the educational and professional outcomes of these individuals, as it often persists into adulthood. Research has mainly focused on behavioral rehabilitation, while little is known about performance changes and neuroplasticity induced by the concurrent application of brain-behavioral approaches. It has been shown that numerical proficiency can be enhanced by applying a small-yet constant-current through the brain, a non-invasive technique named transcranial electrical stimulation (tES). Here we combined a numerical learning paradigm with transcranial direct current stimulation (tDCS) in two adults with DD to assess the potential benefits of this methodology to remediate their numerical difficulties. Subjects learned to associate artificial symbols to numerical quantities within the context of a trial and error paradigm, while tDCS was applied to the posterior parietal cortex (PPC). The first subject (DD1) received anodal stimulation to the right PPC and cathodal stimulation to the left PPC, which has been associated with numerical performance's improvements in healthy subjects. The second subject (DD2) received anodal stimulation to the left PPC and cathodal stimulation to the right PPC, which has been shown to impair numerical performance in healthy subjects. We examined two indices of numerical proficiency: (i) automaticity of number processing; and (ii) mapping of numbers onto space. Our results are opposite to previous findings with non-dyscalculic subjects. Only anodal stimulation to the left PPC improved both indices of numerical proficiency. These initial results represent an important step to inform the rehabilitation of developmental learning disabilities, and have relevant applications for basic and applied research in cognitive neuroscience, rehabilitation, and education.
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Affiliation(s)
- Teresa Iuculano
- Department of Experimental Psychology, University of Oxford Oxford, UK ; Stanford Cognitive and Systems Neuroscience Laboratory, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine Palo Alto, CA, USA ; Institute of Cognitive Neuroscience, University College London London, UK
| | - Roi Cohen Kadosh
- Department of Experimental Psychology, University of Oxford Oxford, UK
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Basic mechanisms of numerical processing: cross-modal number comparisons and symbolic versus nonsymbolic numerosity in the intraparietal sulcus. J Neurosci 2014; 34:1567-9. [PMID: 24478340 DOI: 10.1523/jneurosci.4771-13.2014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Agarwal SM, Shivakumar V, Bose A, Subramaniam A, Nawani H, Chhabra H, Kalmady SV, Narayanaswamy JC, Venkatasubramanian G. Transcranial direct current stimulation in schizophrenia. CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE 2013; 11:118-25. [PMID: 24465247 PMCID: PMC3897759 DOI: 10.9758/cpn.2013.11.3.118] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 12/03/2013] [Accepted: 12/04/2013] [Indexed: 01/01/2023]
Abstract
Transcranial direct current stimulation (tDCS) is an upcoming treatment modality for patients with schizophrenia. A series of recent observations have demonstrated improvement in clinical status of schizophrenia patients with tDCS. This review summarizes the research work that has examined the effects of tDCS in schizophrenia patients with respect to symptom amelioration, cognitive enhancement and neuroplasticity evaluation. tDCS is emerging as a safe, rapid and effective treatment for various aspects of schizophrenia symptoms ranging from auditory hallucinations-for which the effect is most marked, to negative symptoms and cognitive symptoms as well. An interesting line of investigation involves using tDCS for altering and examining neuroplasticity in patients and healthy subjects and is likely to lead to new insights into the neurological aberrations and pathophysiology of schizophrenia. The mechanistic aspects of the technique are discussed in brief. Future work should focus on establishing the clinical efficacy of this novel technique and on evaluating this modality as an adjunct to cognitive enhancement protocols. Understanding the mechanism of action of tDCS as well as the determinants and neurobiological correlates of clinical response to tDCS remains an important goal, which will help us expand the clinical applications of tDCS for the treatment of patients with schizophrenia.
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Affiliation(s)
- Sri Mahavir Agarwal
- The Schizophrenia Clinic, Department of Psychiatry and Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India
| | - Venkataram Shivakumar
- The Schizophrenia Clinic, Department of Psychiatry and Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India
| | - Anushree Bose
- The Schizophrenia Clinic, Department of Psychiatry and Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India
| | - Aditi Subramaniam
- The Schizophrenia Clinic, Department of Psychiatry and Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India
| | - Hema Nawani
- The Schizophrenia Clinic, Department of Psychiatry and Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India
| | - Harleen Chhabra
- The Schizophrenia Clinic, Department of Psychiatry and Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India
| | - Sunil V Kalmady
- The Schizophrenia Clinic, Department of Psychiatry and Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India
| | - Janardhanan C Narayanaswamy
- The Schizophrenia Clinic, Department of Psychiatry and Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India
| | - Ganesan Venkatasubramanian
- The Schizophrenia Clinic, Department of Psychiatry and Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India
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Bikson M, Name A, Rahman A. Origins of specificity during tDCS: anatomical, activity-selective, and input-bias mechanisms. Front Hum Neurosci 2013; 7:688. [PMID: 24155708 PMCID: PMC3800813 DOI: 10.3389/fnhum.2013.00688] [Citation(s) in RCA: 235] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Accepted: 09/30/2013] [Indexed: 01/14/2023] Open
Abstract
Transcranial Direct Current Stimulation (tDCS) is investigated for a broad range of neuropsychiatric indications, various rehabilitation applications, and to modulate cognitive performance in diverse tasks. Specificity of tDCS refers broadly to the ability of tDCS to produce precise, as opposed to diffuse, changes in brain function. Practically, specificity of tDCS implies application-specific customization of protocols to maximize desired outcomes and minimize undesired effects. Especially given the simplicity of tDCS and the complexity of brain function, understanding the mechanisms leading to specificity is fundamental to the rational advancement of tDCS. We define the origins of specificity based on anatomical and functional factors. Anatomical specificity derives from guiding current to targeted brain structures. Functional specificity may derive from either activity-selectivity, where active neuronal networks are preferentially modulated by tDCS, or input-selectivity, where bias is applied to different synaptic inputs. Rational advancement of tDCS may require leveraging all forms of specificity.
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Affiliation(s)
- Marom Bikson
- Department of Biomedical Engineering, The City College of the City University of New York New York, NY, USA
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