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Goldenkoff ER, Deluisi JA, Destiny DP, Lee TG, Michon KJ, Brissenden JA, Taylor SF, Polk TA, Vesia M. The behavioral and neural effects of parietal theta burst stimulation on the grasp network are stronger during a grasping task than at rest. Front Neurosci 2023; 17:1198222. [PMID: 37954875 PMCID: PMC10637360 DOI: 10.3389/fnins.2023.1198222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 10/05/2023] [Indexed: 11/14/2023] Open
Abstract
Repetitive transcranial magnetic stimulation (TMS) is widely used in neuroscience and clinical settings to modulate human cortical activity. The effects of TMS on neural activity depend on the excitability of specific neural populations at the time of stimulation. Accordingly, the brain state at the time of stimulation may influence the persistent effects of repetitive TMS on distal brain activity and associated behaviors. We applied intermittent theta burst stimulation (iTBS) to a region in the posterior parietal cortex (PPC) associated with grasp control to evaluate the interaction between stimulation and brain state. Across two experiments, we demonstrate the immediate responses of motor cortex activity and motor performance to state-dependent parietal stimulation. We randomly assigned 72 healthy adult participants to one of three TMS intervention groups, followed by electrophysiological measures with TMS and behavioral measures. Participants in the first group received iTBS to PPC while performing a grasping task concurrently. Participants in the second group received iTBS to PPC while in a task-free, resting state. A third group of participants received iTBS to a parietal region outside the cortical grasping network while performing a grasping task concurrently. We compared changes in motor cortical excitability and motor performance in the three stimulation groups within an hour of each intervention. We found that parietal stimulation during a behavioral manipulation that activates the cortical grasping network increased downstream motor cortical excitability and improved motor performance relative to stimulation during rest. We conclude that constraining the brain state with a behavioral task during brain stimulation has the potential to optimize plasticity induction in cortical circuit mechanisms that mediate movement processes.
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Affiliation(s)
| | - Joseph A. Deluisi
- School of Kinesiology, University of Michigan, Ann Arbor, MI, United States
| | - Danielle P. Destiny
- Department of Psychology, University of Michigan, Ann Arbor, MI, United States
| | - Taraz G. Lee
- Department of Psychology, University of Michigan, Ann Arbor, MI, United States
| | - Katherine J. Michon
- Department of Psychology, University of Michigan, Ann Arbor, MI, United States
| | - James A. Brissenden
- Department of Psychology, University of Michigan, Ann Arbor, MI, United States
| | - Stephan F. Taylor
- Department of Psychiatry, University of Michigan, Ann Arbor, MI, United States
| | - Thad A. Polk
- Department of Psychology, University of Michigan, Ann Arbor, MI, United States
| | - Michael Vesia
- School of Kinesiology, University of Michigan, Ann Arbor, MI, United States
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2
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Schuler AL, Brkić D, Ferrazzi G, Arcara G, Marinazzo D, Pellegrino G. Auditory white noise exposure results in intrinsic cortical excitability changes. iScience 2023; 26:107387. [PMID: 37575186 PMCID: PMC10415920 DOI: 10.1016/j.isci.2023.107387] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/23/2023] [Accepted: 07/11/2023] [Indexed: 08/15/2023] Open
Abstract
Cortical excitability is commonly measured by applying magnetic stimulation in combination with measuring behavioral response. This measure has, however, some shortcomings including spatial limitation to the primary motor cortex and not accounting for intrinsic excitability fluctuations. Here, we use a measure for intrinsic excitability based on phase synchronization previously validated for epilepsy. We apply this measure in 30 healthy participants' magnetoencephalography (MEG) recordings during the exposure of auditory white noise, a stimulus that has been suggested to modify cortical excitability. Using cortical parcellation of the MEG source data, we could find a specific pattern of increased and decreased excitability while participants are exposed to white noise vs. silence. Specifically, excitability during white noise exposure decreases in the frontal lobe and increases in the temporal lobe. This study thus adds to the understanding of cortical excitability changes due to specific environmental stimuli as well as the spatial extent of these effects.
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Affiliation(s)
- Anna-Lisa Schuler
- IRCCS San Camillo Hospital, Venice, Italy
- Lise Meitner Research Group Cognition and Plasticity, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | | | | | | | - Daniele Marinazzo
- Department of Data Analysis, Faculty of Psychology and Educational Sciences, Ghent University, Ghent, Belgium
| | - Giovanni Pellegrino
- Epilepsy Program, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
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3
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Siebner HR, Funke K, Aberra AS, Antal A, Bestmann S, Chen R, Classen J, Davare M, Di Lazzaro V, Fox PT, Hallett M, Karabanov AN, Kesselheim J, Beck MM, Koch G, Liebetanz D, Meunier S, Miniussi C, Paulus W, Peterchev AV, Popa T, Ridding MC, Thielscher A, Ziemann U, Rothwell JC, Ugawa Y. Transcranial magnetic stimulation of the brain: What is stimulated? - A consensus and critical position paper. Clin Neurophysiol 2022; 140:59-97. [PMID: 35738037 PMCID: PMC9753778 DOI: 10.1016/j.clinph.2022.04.022] [Citation(s) in RCA: 129] [Impact Index Per Article: 64.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 03/14/2022] [Accepted: 04/15/2022] [Indexed: 12/11/2022]
Abstract
Transcranial (electro)magnetic stimulation (TMS) is currently the method of choice to non-invasively induce neural activity in the human brain. A single transcranial stimulus induces a time-varying electric field in the brain that may evoke action potentials in cortical neurons. The spatial relationship between the locally induced electric field and the stimulated neurons determines axonal depolarization. The induced electric field is influenced by the conductive properties of the tissue compartments and is strongest in the superficial parts of the targeted cortical gyri and underlying white matter. TMS likely targets axons of both excitatory and inhibitory neurons. The propensity of individual axons to fire an action potential in response to TMS depends on their geometry, myelination and spatial relation to the imposed electric field and the physiological state of the neuron. The latter is determined by its transsynaptic dendritic and somatic inputs, intrinsic membrane potential and firing rate. Modeling work suggests that the primary target of TMS is axonal terminals in the crown top and lip regions of cortical gyri. The induced electric field may additionally excite bends of myelinated axons in the juxtacortical white matter below the gyral crown. Neuronal excitation spreads ortho- and antidromically along the stimulated axons and causes secondary excitation of connected neuronal populations within local intracortical microcircuits in the target area. Axonal and transsynaptic spread of excitation also occurs along cortico-cortical and cortico-subcortical connections, impacting on neuronal activity in the targeted network. Both local and remote neural excitation depend critically on the functional state of the stimulated target area and network. TMS also causes substantial direct co-stimulation of the peripheral nervous system. Peripheral co-excitation propagates centrally in auditory and somatosensory networks, but also produces brain responses in other networks subserving multisensory integration, orienting or arousal. The complexity of the response to TMS warrants cautious interpretation of its physiological and behavioural consequences, and a deeper understanding of the mechanistic underpinnings of TMS will be critical for advancing it as a scientific and therapeutic tool.
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Affiliation(s)
- Hartwig R Siebner
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark; Department of Neurology, Copenhagen University Hospital Bispebjerg, Copenhagen, Denmark; Institute for Clinical Medicine, University of Copenhagen, Copenhagen, Denmark.
| | - Klaus Funke
- Department of Neurophysiology, Medical Faculty, Ruhr-University Bochum, Bochum, Germany
| | - Aman S Aberra
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
| | - Andrea Antal
- Department of Clinical Neurophysiology, University Medical Center, Georg-August-University, Göttingen, Germany
| | - Sven Bestmann
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom; Wellcome Centre for Human Neuroimaging, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Robert Chen
- Krembil Brain Institute, University Health Network and Division of Neurology, University of Toronto, Toronto, Ontario, Canada
| | - Joseph Classen
- Department of Neurology, University of Leipzig, Leipzig, Germany
| | - Marco Davare
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom; Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
| | - Vincenzo Di Lazzaro
- Unit of Neurology, Neurophysiology, Neurobiology, Department of Medicine, Università Campus Bio-Medico di Roma, via Álvaro del Portillo 21, 00128 Rome, Italy
| | - Peter T Fox
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Mark Hallett
- Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Anke N Karabanov
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark; Department of Nutrition and Exercise, University of Copenhagen, Copenhagen, Denmark
| | - Janine Kesselheim
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
| | - Mikkel M Beck
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
| | - Giacomo Koch
- Department of Neuroscience and Rehabilitation, University of Ferrara, Ferrara, Italy; Non-invasive Brain Stimulation Unit, Laboratorio di NeurologiaClinica e Comportamentale, Fondazione Santa Lucia IRCCS, Rome, Italy
| | - David Liebetanz
- Department of Clinical Neurophysiology, University Medical Center, Georg-August-University, Göttingen, Germany
| | - Sabine Meunier
- Sorbonne Université, Faculté de Médecine, INSERM U 1127, CNRS 4 UMR 7225, Institut du Cerveau, F-75013, Paris, France
| | - Carlo Miniussi
- Center for Mind/Brain Sciences (CIMeC), University of Trento, Italy; Cognitive Neuroscience Section, IRCCS Centro San Giovanni di DioFatebenefratelli, Brescia, Italy
| | - Walter Paulus
- Department of Clinical Neurophysiology, University Medical Center, Georg-August-University, Göttingen, Germany
| | - Angel V Peterchev
- Department of Biomedical Engineering, Duke University, Durham, NC, USA; Department of Psychiatry & Behavioral Sciences, School of Medicine, Duke University, Durham, NC, USA; Department of Electrical & Computer Engineering, Duke University, Durham, NC, USA; Department of Neurosurgery, School of Medicine, Duke University, Durham, NC, USA
| | - Traian Popa
- Center for Neuroprosthetics (CNP) and Brain Mind Institute (BMI), Swiss Federal Institute of Technology (EPFL), Geneva, Switzerland; Center for Neuroprosthetics (CNP) and Brain Mind Institute (BMI), Swiss Federal Institute of Technology (EPFL Valais), Clinique Romande de Réadaptation, Sion, Switzerland
| | - Michael C Ridding
- University of South Australia, IIMPACT in Health, Adelaide, Australia
| | - Axel Thielscher
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark; Department of Health Technology, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Ulf Ziemann
- Department of Neurology & Stroke, University Tübingen, Tübingen, Germany; Hertie Institute for Clinical Brain Research, University Tübingen, Tübingen, Germany
| | - John C Rothwell
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Yoshikazu Ugawa
- Department of Neurology, Fukushima Medical University, Fukushima, Japan; Fukushima Global Medical Science Centre, Advanced Clinical Research Centre, Fukushima Medical University, Fukushima, Japan
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4
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de Graaf TA, Sack AT. When and How to Interpret Null Results in NIBS: A Taxonomy Based on Prior Expectations and Experimental Design. Front Neurosci 2018; 12:915. [PMID: 30618550 PMCID: PMC6297282 DOI: 10.3389/fnins.2018.00915] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 11/21/2018] [Indexed: 02/03/2023] Open
Abstract
Experiments often challenge the null hypothesis that an intervention, for instance application of non-invasive brain stimulation (NIBS), has no effect on an outcome measure. In conventional statistics, a positive result rejects that hypothesis, but a null result is meaningless. Informally, however, researchers often do find null results meaningful to a greater or lesser extent. We present a model to guide interpretation of null results in NIBS research. Along a "gradient of surprise," from Replication nulls through Exploration nulls to Hypothesized nulls, null results can be less or more surprising in the context of prior expectations, research, and theory. This influences to what extent we should credit a null result in this greater context. Orthogonal to this, experimental design choices create a "gradient of interpretability," along which null results of an experiment, considered in isolation, become more informative. This is determined by target localization procedure, neural efficacy checks, and power and effect size evaluations. Along the latter gradient, we concretely propose three "levels of null evidence." With caveats, these proposed levels C, B, and A, classify how informative an empirical null result is along concrete criteria. Lastly, to further inform, and help formalize, the inferences drawn from null results, Bayesian statistics can be employed. We discuss how this increasingly common alternative to traditional frequentist inference does allow quantification of the support for the null hypothesis, relative to support for the alternative hypothesis. It is our hope that these considerations can contribute to the ongoing effort to disseminate null findings alongside positive results to promote transparency and reduce publication bias.
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Affiliation(s)
- Tom A. de Graaf
- Section Brain Stimulation and Cognition, Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands
- Maastricht Brain Imaging Centre, Maastricht, Netherlands
| | - Alexander T. Sack
- Section Brain Stimulation and Cognition, Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands
- Maastricht Brain Imaging Centre, Maastricht, Netherlands
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5
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Cattaneo L. Fancies and Fallacies of Spatial Sampling With Transcranial Magnetic Stimulation (TMS). Front Psychol 2018; 9:1171. [PMID: 30026721 PMCID: PMC6042252 DOI: 10.3389/fpsyg.2018.01171] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 06/18/2018] [Indexed: 11/29/2022] Open
Affiliation(s)
- Luigi Cattaneo
- Dipartimento di Neuroscienze, Biomedicina e Movimento, University of Verona, Verona, Italy
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6
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Shah-Basak PP, Chen P, Caulfield K, Medina J, Hamilton RH. The role of the right superior temporal gyrus in stimulus-centered spatial processing. Neuropsychologia 2018; 113:6-13. [PMID: 29578025 DOI: 10.1016/j.neuropsychologia.2018.03.027] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 03/15/2018] [Accepted: 03/21/2018] [Indexed: 10/17/2022]
Abstract
Although emerging neuropsychological evidence supports the involvement of temporal areas, and in particular the right superior temporal gyrus (STG), in allocentric neglect deficits, the role of STG in healthy spatial processing remains elusive. While several functional brain imaging studies have demonstrated involvement of the STG in tasks involving explicit stimulus-centered judgments, prior rTMS studies targeting the right STG did not find the expected neglect-like rightward bias in size judgments using the conventional landmark task. The objective of the current study was to investigate whether disruption of the right STG using inhibitory repetitive transcranial magnetic stimulation (rTMS) could impact stimulus-centered, allocentric spatial processing in healthy individuals. A lateralized version of the landmark task was developed to accentuate the dissociation between viewer-centered and stimulus-centered reference frames. We predicted that inhibiting activity in the right STG would decrease accuracy because of induced rightward bias centered on the line stimulus irrespective of its viewer-centered or egocentric locations. Eleven healthy, right-handed adults underwent the lateralized landmark task. After viewing each stimulus, participants had to judge whether the line was bisected, or whether the left (left-long trials) or the right segment (right-long trials) of the line was longer. Participants repeated the task before (pre-rTMS) and after (post-rTMS) receiving 20 min of 1 Hz rTMS over the right STG, the right supramarginal gyrus (SMG), and the vertex (a control site) during three separate visits. Linear mixed models for binomial data were generated with either accuracy or judgment errors as dependent variables, to compare 1) performance across trial types (bisection, non-bisection), and 2) pre- vs. post-rTMS performance between the vertex and the STG and the vertex and the SMG. Line eccentricity (z = 4.31, p < 0.0001) and line bisection (z = 5.49, p < 0.0001) were significant predictors of accuracy. In the models comparing the effects of rTMS, a significant two-way interaction with STG (z = -3.09, p = 0.002) revealed a decrease in accuracy of 9.5% and an increase in errors of the right-long type by 10.7% on bisection trials, in both left and right viewer-centered locations. No significant changes in leftward errors were found. These findings suggested an induced stimulus-centered rightward bias in our participants after STG stimulation. Notably, accuracy or errors were not influenced by SMG stimulation compared to vertex. In line with our predictions, the findings provide compelling evidence for right STG's involvement in healthy stimulus-centered spatial processing.
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Affiliation(s)
- Priyanka P Shah-Basak
- Laboratory for Cognition and Neural Stimulation, University of Pennsylvania, Philadelphia, PA, USA
| | - Peii Chen
- Kessler Foundation, West Orange, NJ, USA; Department of Physical Medicine and Rehabilitation, Rutgers University, Newark, NJ, USA
| | - Kevin Caulfield
- Laboratory for Cognition and Neural Stimulation, University of Pennsylvania, Philadelphia, PA, USA
| | - Jared Medina
- Department of Psychology, University of Delaware, Newark, DE, USA
| | - Roy H Hamilton
- Laboratory for Cognition and Neural Stimulation, University of Pennsylvania, Philadelphia, PA, USA; Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA.
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7
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Leitão J, Thielscher A, Lee H, Tuennerhoff J, Noppeney U. Transcranial magnetic stimulation of right inferior parietal cortex causally influences prefrontal activation for visual detection. Eur J Neurosci 2017; 46:2807-2816. [DOI: 10.1111/ejn.13743] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 10/02/2017] [Accepted: 10/02/2017] [Indexed: 11/29/2022]
Affiliation(s)
- Joana Leitão
- Max Planck Institute for Biological Cybernetics Tübingen Germany
- Computational Neuroscience and Cognitive Robotics Centre University of Birmingham B15 2TT Birmingham UK
- Laboratory for Behavioral Neurology and Imaging of Cognition Department of Neuroscience University of Geneva Geneva Switzerland
| | - Axel Thielscher
- Max Planck Institute for Biological Cybernetics Tübingen Germany
- Department of Electrical Engineering Technical University of Denmark Lyngby Denmark
- DRCMR Copenhagen University Hospital Hvidovre Hvidovre Denmark
| | - Hweeling Lee
- Max Planck Institute for Biological Cybernetics Tübingen Germany
- German Center for Neurodegenerative Diseases (DZNE) Bonn Germany
| | - Johannes Tuennerhoff
- Max Planck Institute for Biological Cybernetics Tübingen Germany
- University Clinic of Neurology Tübingen Germany
| | - Uta Noppeney
- Max Planck Institute for Biological Cybernetics Tübingen Germany
- Computational Neuroscience and Cognitive Robotics Centre University of Birmingham B15 2TT Birmingham UK
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8
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Leitão J, Thielscher A, Tuennerhoff J, Noppeney U. Comparing TMS perturbations to occipital and parietal cortices in concurrent TMS-fMRI studies-Methodological considerations. PLoS One 2017; 12:e0181438. [PMID: 28767670 PMCID: PMC5540584 DOI: 10.1371/journal.pone.0181438] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 06/30/2017] [Indexed: 02/07/2023] Open
Abstract
Neglect and hemianopia are two neuropsychological syndromes that are associated with reduced awareness for visual signals in patients’ contralesional hemifield. They offer the unique possibility to dissociate the contributions of retino-geniculate and retino-colliculo circuitries in visual perception. Yet, insights from patient fMRI studies are limited by heterogeneity in lesion location and extent, long-term functional reorganization and behavioural compensation after stroke. Transcranial magnetic stimulation (TMS) has therefore been proposed as a complementary method to investigate the effect of transient perturbations on functional brain organization. This concurrent TMS-fMRI study applied TMS perturbation to occipital and parietal cortices with the aim to ‘mimick’ neglect and hemianopia. Based on the challenges and interpretational limitations of our own study we aim to provide tutorial guidance on how future studies should compare TMS to primary sensory and association areas that are governed by distinct computational principles, neural dynamics and functional architecture.
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Affiliation(s)
- Joana Leitão
- Max Planck Institute for biological Cybernetics, Tübingen, Germany
- Computational Neuroscience and Cognitive Robotics Centre, University of Birmingham, Birmingham, United Kingdom
- Laboratory for Behavioral Neurology and Imaging of Cognition, Department of Neuroscience, University of Geneva, Geneva, Switzerland
- * E-mail:
| | - Axel Thielscher
- Max Planck Institute for biological Cybernetics, Tübingen, Germany
- Department of Electrical Engineering, Technical University of Denmark, Lyngby, Denmark
- DRCMR, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
| | - Johannes Tuennerhoff
- Max Planck Institute for biological Cybernetics, Tübingen, Germany
- University Clinic of Neurology, Tübingen, Germany
| | - Uta Noppeney
- Max Planck Institute for biological Cybernetics, Tübingen, Germany
- Computational Neuroscience and Cognitive Robotics Centre, University of Birmingham, Birmingham, United Kingdom
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9
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Zuanazzi A, Cattaneo L. The right hemisphere is independent from the left hemisphere in allocating visuospatial attention. Neuropsychologia 2017; 102:197-205. [PMID: 28602998 DOI: 10.1016/j.neuropsychologia.2017.06.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2016] [Revised: 06/07/2017] [Accepted: 06/08/2017] [Indexed: 01/17/2023]
Abstract
The capacity to allocate visuospatial attention is traditionally considered right-lateralized according to the effects of unilateral cerebral lesions. Contralateral hemi-spatial neglect occurs much more frequently after lesions of the right hemisphere, which has therefore been dubbed as 'dominant'. This pattern of symptoms is supported by functional models that postulate either independence or reciprocal influences between the two hemispheres. Here we specifically explored the dependency of the right hemisphere (RH) from the left hemisphere (LH) in spatial attention. We capitalized on the well-known effect of online transcranial magnetic stimulation (TMS) on the RH in healthy individuals, consisting in transient neglect-like manifestations in the left hemi-space. We assessed whether prior stimulation of the left posterior parietal cortex with a long-lasting neuromodulatory procedure (transcranial direct current stimulation - tDCS) affected the acute effects of TMS on the right posterior parietal cortex. We performed a within-subjects factorial study with two factors: LH tDCS (sham or real) and RH TMS (sham or real), resulting in a 2×2 design. The effects on spatial attention were examined separately for the two hemi-spaces by means of a modified line-bisection task. The results indicated that TMS over the RH produced a spatial attention deficit in the left hemi-space alone and the behavioural effects of TMS were not modulated by prior stimulation of the LH. Interestingly, additional analyses showed that tDCS over the LH alone produced a deficit in spatial attention to the right hemi-space. We interpret the current results as evidence for a largely independent contribution of each hemisphere to the allocation of visuospatial attention limited to the contralateral hemi-space.
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Affiliation(s)
| | - Luigi Cattaneo
- Department of Neurosciences, Biomedicine and Movement, University of Verona, Verona, Italy.
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10
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Veniero D, Strüber D, Thut G, Herrmann CS. Noninvasive Brain Stimulation Techniques Can Modulate Cognitive Processing. ORGANIZATIONAL RESEARCH METHODS 2016. [DOI: 10.1177/1094428116658960] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Recent methods that allow a noninvasive modulation of brain activity are able to modulate human cognitive behavior. Among these methods are transcranial electric stimulation and transcranial magnetic stimulation that both come in multiple variants. A property of both types of brain stimulation is that they modulate brain activity and in turn modulate cognitive behavior. Here, we describe the methods with their assumed neural mechanisms for readers from the economic and social sciences and little prior knowledge of these techniques. Our emphasis is on available protocols and experimental parameters to choose from when designing a study. We also review a selection of recent studies that have successfully applied them in the respective field. We provide short pointers to limitations that need to be considered and refer to the relevant papers where appropriate.
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Affiliation(s)
- Domenica Veniero
- Institute of Neuroscience and Psychology, University of Glasgow, Glasgow, United Kingdom
| | - Daniel Strüber
- Experimental Psychology Lab, Center for Excellence ‘Hearing4all’, European Medical School, Carl von Ossietzky Universität, Oldenburg, Germany
- Research Center Neurosensory Science, Carl von Ossietzky Universität, Oldenburg, Germany
| | - Gregor Thut
- Institute of Neuroscience and Psychology, University of Glasgow, Glasgow, United Kingdom
| | - Christoph S. Herrmann
- Experimental Psychology Lab, Center for Excellence ‘Hearing4all’, European Medical School, Carl von Ossietzky Universität, Oldenburg, Germany
- Research Center Neurosensory Science, Carl von Ossietzky Universität, Oldenburg, Germany
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11
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Abstract
UNLABELLED Adaptive behavior relies on combining bottom-up sensory inputs with top-down control signals to guide responses in line with current goals and task demands. Over the past decade, accumulating evidence has suggested that the dorsal and ventral frontoparietal attentional systems are recruited interactively in this process. This fMRI study used concurrent transcranial magnetic stimulation (TMS) as a causal perturbation approach to investigate the interactions between dorsal and ventral attentional systems and sensory processing areas. In a sustained spatial attention paradigm, human participants detected weak visual targets that were presented in the lower-left visual field on 50% of the trials. Further, we manipulated the presence/absence of task-irrelevant auditory signals. Critically, on each trial we applied 10 Hz bursts of four TMS (or Sham) pulses to the intraparietal sulcus (IPS). IPS-TMS relative to Sham-TMS increased activation in the parietal cortex regardless of sensory stimulation, confirming the neural effectiveness of TMS stimulation. Visual targets increased activations in the anterior insula, a component of the ventral attentional system responsible for salience detection. Conversely, they decreased activations in the ventral visual areas. Importantly, IPS-TMS abolished target-evoked activation increases in the right temporoparietal junction (TPJ) of the ventral attentional system, whereas it eliminated target-evoked activation decreases in the right fusiform. Our results demonstrate that IPS-TMS exerts profound directional causal influences not only on visual areas but also on the TPJ as a critical component of the ventral attentional system. They reveal a complex interplay between dorsal and ventral attentional systems during target detection under sustained spatial attention. SIGNIFICANCE STATEMENT Adaptive behavior relies on combining bottom-up sensory inputs with top-down attentional control. Although the dorsal and ventral frontoparietal systems are key players in attentional control, their distinct contributions remain unclear. In this TMS-fMRI study, participants attended to the left visual field to detect weak visual targets presented on half of the trials. We applied brief TMS bursts (or Sham-TMS) to the dorsal intraparietal sulcus (IPS) 100 ms after visual stimulus onset. IPS-TMS abolished the visual induced response suppression in the ventral occipitotemporal cortex and the response enhancement to visual targets in the temporoparietal junction. Our results demonstrate that IPS causally influences neural activity in the ventral attentional system 100 ms poststimulus. They have important implications for our understanding of the neural mechanisms underlying attentional control.
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12
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Reichenbach A, Bresciani JP, Bülthoff HH, Thielscher A. Reaching with the sixth sense: Vestibular contributions to voluntary motor control in the human right parietal cortex. Neuroimage 2015; 124:869-875. [PMID: 26424179 DOI: 10.1016/j.neuroimage.2015.09.043] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 09/15/2015] [Accepted: 09/20/2015] [Indexed: 11/25/2022] Open
Abstract
The vestibular system constitutes the silent sixth sense: It automatically triggers a variety of vital reflexes to maintain postural and visual stability. Beyond their role in reflexive behavior, vestibular afferents contribute to several perceptual and cognitive functions and also support voluntary control of movements by complementing the other senses to accomplish the movement goal. Investigations into the neural correlates of vestibular contribution to voluntary action in humans are challenging and have progressed far less than research on corresponding visual and proprioceptive involvement. Here, we demonstrate for the first time with event-related TMS that the posterior part of the right medial intraparietal sulcus processes vestibular signals during a goal-directed reaching task with the dominant right hand. This finding suggests a qualitative difference between the processing of vestibular vs. visual and proprioceptive signals for controlling voluntary movements, which are pre-dominantly processed in the left posterior parietal cortex. Furthermore, this study reveals a neural pathway for vestibular input that might be distinct from the processing for reflexive or cognitive functions, and opens a window into their investigation in humans.
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Affiliation(s)
- Alexandra Reichenbach
- Max Planck Institute for Biological Cybernetics, Spemannstr. 38, 72076 Tübingen, Germany.
| | - Jean-Pierre Bresciani
- Max Planck Institute for Biological Cybernetics, Spemannstr. 38, 72076 Tübingen, Germany; Laboratoire de Psychologie et NeuroCognition, University of Grenoble, BP47, 38040 Grenoble, Cedex 9, France; Department of Medicine, University of Fribourg, Boulevard de Pérolles 90, 1700 Fribourg, Switzerland
| | - Heinrich H Bülthoff
- Max Planck Institute for Biological Cybernetics, Spemannstr. 38, 72076 Tübingen, Germany; Dept. of Brain and Cognitive Engineering, Korea University, Anam-dong 5ga, Seonbuk-gu, Seoul 136-713, Republic of Korea.
| | - Axel Thielscher
- Max Planck Institute for Biological Cybernetics, Spemannstr. 38, 72076 Tübingen, Germany; Danish Research Center for Magnetic Resonance, Copenhagen University Hospital, Kettegård Alle 30, 2650 Hvidovre, Denmark; Biomedical Engineering Section, Technical University of Denmark, Anker Engelunds Vej 1, Building 101A, 2800 Kgs. Lyngby, Denmark
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13
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Giglia G, Pia L, Folegatti A, Puma A, Fierro B, Cosentino G, Berti A, Brighina F. Far Space Remapping by Tool Use: A rTMS Study Over the Right Posterior Parietal Cortex. Brain Stimul 2015; 8:795-800. [PMID: 25732371 DOI: 10.1016/j.brs.2015.01.412] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2014] [Revised: 12/14/2014] [Accepted: 01/23/2015] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND In previous studies, rTMS has been successfully employed to interfere with the right posterior parietal cortex (rPPC) inducing neglect-like behavior in healthy subjects. Several studies have shown that the use of tools can modulate the boundaries between near and far space: indeed when far space is reached by the stick, far space can be remapped as near. OBJECTIVE The aim of the present study was to investigate whether once that rTMS on the rPPC has selectively induced neglect-like bias in the near space (but not in the far space), neglect can appears also in the far space when the subjects used a tool to perform the task. METHODS Fifteen right-handed healthy subjects executed a line length judgment task in two different spatial positions (60 cm: near space and 120 cm: far space), with or without rPPC on-line rTMS. In the far space condition, subjects performed the perceptual task while holding or not a tool. RESULTS During rTMS, visuospatial performance significantly shifted toward right when the task was performed in the near space and in the far space when the tool was used. No significant effect was found when rTMS was delivered in the far space condition without tool use. CONCLUSIONS Our results demonstrate that the application of rTMS on rPPC, specifically affect the representation of near space because it caused neglect both when the subjects acted in the near space and when they acted in a far space that was remapped as near by the use of a tool.
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Affiliation(s)
- Giuseppe Giglia
- Department of Cognitive Neuroscience, Maastricht University, Maastricht, Netherlands; Hypatia School of Medicine of Caltanissetta - Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, Palermo, Italy
| | - Lorenzo Pia
- SAMBA (SpAtial, Motor & Bodily Awareness) Research Group, Psychology Department, University of Turin, Italy; Neuroscience Institute of Turin (NIT), University of Turin, Italy
| | - Alessia Folegatti
- SAMBA (SpAtial, Motor & Bodily Awareness) Research Group, Psychology Department, University of Turin, Italy; Neuroscience Institute of Turin (NIT), University of Turin, Italy
| | - Angela Puma
- Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, Palermo, Italy
| | - Brigida Fierro
- Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, Palermo, Italy.
| | - Giuseppe Cosentino
- Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, Palermo, Italy
| | - Anna Berti
- SAMBA (SpAtial, Motor & Bodily Awareness) Research Group, Psychology Department, University of Turin, Italy; Neuroscience Institute of Turin (NIT), University of Turin, Italy
| | - Filippo Brighina
- Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, Palermo, Italy
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14
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Salatino A, Poncini M, George MS, Ricci R. Hunting for right and left parietal hot spots using single-pulse TMS: modulation of visuospatial perception during line bisection judgment in the healthy brain. Front Psychol 2014; 5:1238. [PMID: 25400612 PMCID: PMC4215615 DOI: 10.3389/fpsyg.2014.01238] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Accepted: 10/11/2014] [Indexed: 11/25/2022] Open
Abstract
A series of studies have consistently reproduced left neglect-like bias on line length estimation tasks in healthy participants by applying transcranial magnetic stimulation (TMS) over the right posterior parietal cortex (PPC), while no significant changes have been reported when stimulating the left PPC. However, a notable inter-individual variability in the right parietal site where TMS modulates visuospatial perception can be observed, and no general agreement exists on how to identify the optimal parietal site of stimulation. In the present study, we propose a new site-finding TMS protocol to easily identify the optimum parietal location, or “hot spot,” where TMS may modulate visuospatial perception on a line length estimation task (the Landmark task). Single-pulse TMS at 115% of motor threshold was applied 150 ms after the visual stimulus onset over nine different sites of a 3 cm × 3 cm grid, centred over right or left PPC (P4 and P3 according to the 10–20 EEG system, respectively) in eight healthy participants. Stimulation of right PPC induced a significant left neglect-like bias, when the coil was applied over the most posterior and dorso-posterior sites. Unexpectedly, TMS over left PPC also produced left neglect-like bias. However, in this case significant effects were found when targeting the most anterior and dorso-anterior portions of the grid. These results are discussed in relation to recent findings on neural networks underlying spatial cognition. The hunting protocol we propose might offer an economical and easy-to-use tool to functionally identify the optimal parietal site where TMS can modulate visuospatial perception, in healthy subjects and possibly in post-stroke patients undergoing repetitive transcranial magnetic stimulation treatment.
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Affiliation(s)
- Adriana Salatino
- Dipartimento di Psicologia, Università di Torino Torino, Italy ; Brain Stimulation Lab and Center for Advanced Imaging Research, Medical University of South Carolina Charleston, SC, USA
| | - Marisa Poncini
- Dipartimento di Psicologia, Università di Torino Torino, Italy
| | - Mark S George
- Brain Stimulation Lab and Center for Advanced Imaging Research, Medical University of South Carolina Charleston, SC, USA
| | - Raffaella Ricci
- Dipartimento di Psicologia, Università di Torino Torino, Italy ; Brain Stimulation Lab and Center for Advanced Imaging Research, Medical University of South Carolina Charleston, SC, USA
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15
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TMS stimulation over the inferior parietal cortex disrupts prospective sense of agency. Brain Struct Funct 2014; 220:3627-39. [DOI: 10.1007/s00429-014-0878-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Accepted: 08/11/2014] [Indexed: 11/26/2022]
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16
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Kheradmand A, Lasker A, Zee DS. Transcranial magnetic stimulation (TMS) of the supramarginal gyrus: a window to perception of upright. Cereb Cortex 2013; 25:765-71. [PMID: 24084127 DOI: 10.1093/cercor/bht267] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Although the pull of gravity, primarily detected by the labyrinth, is the fundamental input for our sense of upright, vision and proprioception must also be integrated with vestibular information into a coherent perception of spatial orientation. Here, we used transcranial magnetic stimulation (TMS) to probe the role of the cortex at the temporal parietal junction (TPJ) of the right cerebral hemisphere in the perception of upright. We measured the perceived vertical orientation of a visual line; that is, the subjective visual vertical (SVV), after a short period of continuous theta burst stimulation (cTBS) with the head upright. cTBS over the posterior aspect of the supramarginal gyrus (SMGp) in 8 right-handed subjects consistently tilted the perception of upright when tested with the head tilted 20° to either shoulder (right: 3.6°, left: 2.7°). The tilt of SVV was always in the direction opposite to the head tilt. On the other hand, there was no significant tilt after sham stimulation or after cTBS of nearby areas. These findings suggest that a small area of cerebral cortex--SMGp--has a role in processing information from different sensory modalities into an accurate perception of upright.
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Affiliation(s)
- Amir Kheradmand
- Department of Neurology Department of Otolaryngology-Head and Neck Surgery
| | | | - David S Zee
- Department of Neurology Department of Otolaryngology-Head and Neck Surgery Department of Ophthalmology Department of Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
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17
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Reichenbach A, Thielscher A, Peer A, Bülthoff HH, Bresciani JP. A key region in the human parietal cortex for processing proprioceptive hand feedback during reaching movements. Neuroimage 2013; 84:615-25. [PMID: 24060316 DOI: 10.1016/j.neuroimage.2013.09.024] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Revised: 08/09/2013] [Accepted: 09/16/2013] [Indexed: 12/20/2022] Open
Abstract
Seemingly effortless, we adjust our movements to continuously changing environments. After initiation of a goal-directed movement, the motor command is under constant control of sensory feedback loops. The main sensory signals contributing to movement control are vision and proprioception. Recent neuroimaging studies have focused mainly on identifying the parts of the posterior parietal cortex (PPC) that contribute to visually guided movements. We used event-related TMS and force perturbations of the reaching hand to test whether the same sub-regions of the left PPC contribute to the processing of proprioceptive-only and of multi-sensory information about hand position when reaching for a visual target. TMS over two distinct stimulation sites elicited differential effects: TMS applied over the posterior part of the medial intraparietal sulcus (mIPS) compromised reaching accuracy when proprioception was the only sensory information available for correcting the reaching error. When visual feedback of the hand was available, TMS over the anterior intraparietal sulcus (aIPS) prolonged reaching time. Our results show for the first time the causal involvement of the posterior mIPS in processing proprioceptive feedback for online reaching control, and demonstrate that distinct cortical areas process proprioceptive-only and multi-sensory information for fast feedback corrections.
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Affiliation(s)
- Alexandra Reichenbach
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany; Institute of Cognitive Neuroscience, University College London, UK.
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18
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Leitão J, Thielscher A, Werner S, Pohmann R, Noppeney U. Effects of parietal TMS on visual and auditory processing at the primary cortical level -- a concurrent TMS-fMRI study. ACTA ACUST UNITED AC 2012; 23:873-84. [PMID: 22490546 DOI: 10.1093/cercor/bhs078] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Accumulating evidence suggests that multisensory interactions emerge already at the primary cortical level. Specifically, auditory inputs were shown to suppress activations in visual cortices when presented alone but amplify the blood oxygen level-dependent (BOLD) responses to concurrent visual inputs (and vice versa). This concurrent transcranial magnetic stimulation-functional magnetic resonance imaging (TMS-fMRI) study applied repetitive TMS trains at no, low, and high intensity over right intraparietal sulcus (IPS) and vertex to investigate top-down influences on visual and auditory cortices under 3 sensory contexts: visual, auditory, and no stimulation. IPS-TMS increased activations in auditory cortices irrespective of sensory context as a result of direct and nonspecific auditory TMS side effects. In contrast, IPS-TMS modulated activations in the visual cortex in a state-dependent fashion: it deactivated the visual cortex under no and auditory stimulation but amplified the BOLD response to visual stimulation. However, only the response amplification to visual stimulation was selective for IPS-TMS, while the deactivations observed for IPS- and Vertex-TMS resulted from crossmodal deactivations induced by auditory activity to TMS sounds. TMS to IPS may increase the responses in visual (or auditory) cortices to visual (or auditory) stimulation via a gain control mechanism or crossmodal interactions. Collectively, our results demonstrate that understanding TMS effects on (uni)sensory processing requires a multisensory perspective.
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Affiliation(s)
- Joana Leitão
- Cognitive Neuroimaging Group, Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany.
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19
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Hesse MD, Sparing R, Fink GR. Ameliorating spatial neglect with non-invasive brain stimulation: From pathophysiological concepts to novel treatment strategies. Neuropsychol Rehabil 2011; 21:676-702. [DOI: 10.1080/09602011.2011.573931] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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20
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de Graaf T, Sack A. Null results in TMS: From absence of evidence to evidence of absence. Neurosci Biobehav Rev 2011; 35:871-7. [DOI: 10.1016/j.neubiorev.2010.10.006] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2010] [Revised: 10/08/2010] [Accepted: 10/11/2010] [Indexed: 10/18/2022]
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21
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Specificity of human parietal saccade and reach regions during transcranial magnetic stimulation. J Neurosci 2010; 30:13053-65. [PMID: 20881123 DOI: 10.1523/jneurosci.1644-10.2010] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Single-unit recordings in macaque monkeys have identified effector-specific regions in posterior parietal cortex (PPC), but functional neuroimaging in the human has yielded controversial results. Here we used on-line repetitive transcranial magnetic stimulation (rTMS) to determine saccade and reach specificity in human PPC. A short train of three TMS pulses (separated by an interval of 100 ms) was delivered to superior parieto-occipital cortex (SPOC), a region over the midposterior intraparietal sulcus (mIPS), and a site close to caudal IPS situated over the angular gyrus (AG) during a brief memory interval while subjects planned either a saccade or reach with the left or right hand. Behavioral measures then were compared to controls without rTMS. Stimulation of mIPS and AG produced similar patterns: increased end-point variability for reaches and decreased saccade accuracy for contralateral targets. In contrast, stimulation of SPOC deviated reach end points toward visual fixation and had no effect on saccades. Contralateral-limb specificity was highest for AG and lowest for SPOC. Visual feedback of the hand negated rTMS-induced disruptions of the reach plan for mIPS and AG, but not SPOC. These results suggest that human SPOC is specialized for encoding retinally peripheral reach goals, whereas more anterior-lateral regions (mIPS and AG) along the IPS possess overlapping maps for saccade and reach planning and are more closely involved in motor details (i.e., planning the reach vector for a specific hand). This work provides the first causal evidence for functional specificity of these parietal regions in healthy humans.
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The use of transcranial magnetic stimulation in cognitive neuroscience: a new synthesis of methodological issues. Neurosci Biobehav Rev 2010; 35:516-36. [PMID: 20599555 DOI: 10.1016/j.neubiorev.2010.06.005] [Citation(s) in RCA: 221] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Revised: 06/15/2010] [Accepted: 06/17/2010] [Indexed: 10/19/2022]
Abstract
Transcranial magnetic stimulation (TMS) has become a mainstay of cognitive neuroscience, thus facing new challenges due to its widespread application on behaviorally silent areas. In this review we will summarize the main technical and methodological considerations that are necessary when using TMS in cognitive neuroscience, based on a corpus of studies and technical improvements that has become available in most recent years. Although TMS has been applied only relatively recently on a large scale to the study of higher functions, a range of protocols that elucidate how this technique can be used to investigate a variety of issues is already available, such as single pulse, paired pulse, dual-site, repetitive and theta burst TMS. Finally, we will touch on recent promising approaches that provide powerful new insights about causal interactions among brain regions (i.e., TMS with other neuroimaging techniques) and will enable researchers to enhance the functional resolution of TMS (i.e., state-dependent TMS). We will end by briefly summarizing and discussing the implications of the newest safety guidelines.
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