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Holopainen K, Sihvonen AJ, Kauramäki J, Särkämö T, Shulga A. The effects of music combined to paired associative stimulation on motor-evoked potentials and alertness in spinal cord injury patients and healthy subjects. Sci Rep 2024; 14:10194. [PMID: 38702398 PMCID: PMC11068768 DOI: 10.1038/s41598-024-60984-w] [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: 11/27/2023] [Accepted: 04/29/2024] [Indexed: 05/06/2024] Open
Abstract
Paired associative stimulation (PAS) consisting of high-intensity transcranial magnetic stimulation (TMS) and high-frequency peripheral nerve stimulation (known as high-PAS) induces plastic changes and improves motor performance in patients with incomplete spinal cord injury (SCI). Listening to music during PAS may potentially improve mood and arousal and facilitate PAS-induced neuroplasticity via auditory-motor coupling, but the effects have not been explored. This pilot study aimed to determine if the effect of high-PAS on motor-evoked potentials (MEPs) and subjective alertness can be augmented with music. Ten healthy subjects and nine SCI patients received three high-PAS sessions in randomized order (PAS only, PAS with music synchronized to TMS, PAS with self-selected music). MEPs were measured before (PRE), after (POST), 30 min (POST30), and 60 min (POST60) after stimulation. Alertness was evaluated with a questionnaire. In healthy subjects, MEPs increased at POST in all sessions and remained higher at POST60 in PAS with synchronized music compared with the other sessions. There was no difference in alertness. In SCI patients, MEPs increased at POST and POST30 in PAS only but not in other sessions, whereas alertness was higher in PAS with self-selected music. More research is needed to determine the potential clinical effects of using music during high-PAS.
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Affiliation(s)
- Kirsi Holopainen
- BioMag Laboratory, HUS Diagnostic Centre, Helsinki University Hospital, University of Helsinki and Aalto University School of Science, Helsinki, Finland
| | - Aleksi J Sihvonen
- Cognitive Brain Research Unit, Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki, Finland
- Centre of Excellence in Music, Mind, Body and Brain, University of Helsinki, Helsinki, Finland
- Clinical Neurosciences, Neurology, Faculty of Medicine, University of Helsinki, Helsinki, Finland
- Department of Neurology, Neurocenter, Helsinki University Hospital, Helsinki, Finland
| | - Jaakko Kauramäki
- Cognitive Brain Research Unit, Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki, Finland
- Centre of Excellence in Music, Mind, Body and Brain, University of Helsinki, Helsinki, Finland
| | - Teppo Särkämö
- Cognitive Brain Research Unit, Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki, Finland
- Centre of Excellence in Music, Mind, Body and Brain, University of Helsinki, Helsinki, Finland
| | - Anastasia Shulga
- BioMag Laboratory, HUS Diagnostic Centre, Helsinki University Hospital, University of Helsinki and Aalto University School of Science, Helsinki, Finland.
- Department of Physical and Rehabilitation Medicine, Helsinki University Hospital and University of Helsinki, Helsinki, Finland.
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2
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Eysel UT, Jancke D. Induction of excitatory brain state governs plastic functional changes in visual cortical topology. Brain Struct Funct 2024; 229:531-547. [PMID: 38041743 PMCID: PMC10978694 DOI: 10.1007/s00429-023-02730-y] [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: 08/09/2023] [Accepted: 11/03/2023] [Indexed: 12/03/2023]
Abstract
Adult visual plasticity underlying local remodeling of the cortical circuitry in vivo appears to be associated with a spatiotemporal pattern of strongly increased spontaneous and evoked activity of populations of cells. Here we review and discuss pioneering work by us and others about principles of plasticity in the adult visual cortex, starting with our study which showed that a confined lesion in the cat retina causes increased excitability in the affected region in the primary visual cortex accompanied by fine-tuned restructuring of neuronal function. The underlying remodeling processes was further visualized with voltage-sensitive dye (VSD) imaging that allowed a direct tracking of retinal lesion-induced reorganization across horizontal cortical circuitries. Nowadays, application of noninvasive stimulation methods pursues the idea further of increased cortical excitability along with decreased inhibition as key factors for the induction of adult cortical plasticity. We used high-frequency transcranial magnetic stimulation (TMS), for the first time in combination with VSD optical imaging, and provided evidence that TMS-amplified excitability across large pools of neurons forms the basis for noninvasively targeting reorganization of orientation maps in the visual cortex. Our review has been compiled on the basis of these four own studies, which we discuss in the context of historical developments in the field of visual cortical plasticity and the current state of the literature. Overall, we suggest markers of LTP-like cortical changes at mesoscopic population level as a main driving force for the induction of visual plasticity in the adult. Elevations in excitability that predispose towards cortical plasticity are most likely a common property of all cortical modalities. Thus, interventions that increase cortical excitability are a promising starting point to drive perceptual and potentially motor learning in therapeutic applications.
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Affiliation(s)
- Ulf T Eysel
- Department of Neurophysiology, Ruhr University Bochum, 44780, Bochum, Germany.
| | - Dirk Jancke
- Optical Imaging Group, Institut für Neuroinformatik, Ruhr University Bochum, 44780, Bochum, Germany.
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Chiappini E, Turrini S, Zanon M, Marangon M, Borgomaneri S, Avenanti A. Driving Hebbian plasticity over ventral premotor-motor projections transiently enhances motor resonance. Brain Stimul 2024; 17:211-220. [PMID: 38387557 DOI: 10.1016/j.brs.2024.02.011] [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: 09/07/2023] [Revised: 12/23/2023] [Accepted: 02/16/2024] [Indexed: 02/24/2024] Open
Abstract
BACKGROUND Making sense of others' actions relies on the activation of an action observation network (AON), which maps visual information about observed actions onto the observer's motor system. This motor resonance process manifests in the primary motor cortex (M1) as increased corticospinal excitability finely tuned to the muscles engaged in the observed action. Motor resonance in M1 is facilitated by projections from higher-order AON regions. However, whether manipulating the strength of AON-to-M1 connectivity affects motor resonance remains unclear. METHODS We used transcranial magnetic stimulation (TMS) in 48 healthy humans. Cortico-cortical paired associative stimulation (ccPAS) was administered over M1 and the ventral premotor cortex (PMv), a key AON node, to induce spike-timing-dependent plasticity (STDP) in the pathway connecting them. Single-pulse TMS assessed motor resonance during action observation. RESULTS Before ccPAS, action observation increased corticospinal excitability in the muscles corresponding to the observed movements, reflecting motor resonance in M1. Notably, ccPAS aimed at strengthening projections from PMv to M1 (PMv→M1) induced short-term enhancement of motor resonance. The enhancement specifically occurred with the ccPAS configuration consistent with forward PMv→M1 projections and dissipated 20 min post-stimulation; ccPAS administered in the reverse order (M1→PMv) and sham stimulation did not affect motor resonance. CONCLUSIONS These findings provide the first evidence that inducing STDP to strengthen PMv input to M1 neurons causally enhances muscle-specific motor resonance in M1. Our study sheds light on the plastic mechanisms that shape AON functionality and demonstrates that exogenous manipulation of AON connectivity can influence basic mirror mechanisms that underlie social perception.
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Affiliation(s)
- Emilio Chiappini
- Department of Clinical and Health Psychology, University of Vienna, 1010, Vienna, Austria; Centro Studi e Ricerche in Neuroscienze Cognitive, Dipartimento di Psicologia "Renzo Canestrari", Campus di Cesena, Alma Mater Studiorum Università di Bologna, 47521, Cesena, Italy; Department of Psychology and Neurosciences, Leibniz Research Centre for Working Environment and Human Factors (IfADo), 44139, Dortmund, Germany.
| | - Sonia Turrini
- Centro Studi e Ricerche in Neuroscienze Cognitive, Dipartimento di Psicologia "Renzo Canestrari", Campus di Cesena, Alma Mater Studiorum Università di Bologna, 47521, Cesena, Italy; Precision Neuroscience & Neuromodulation Program, Gordon Center for Medical Imaging, Massachusetts General Hospital & Harvard Medical School, Boston, MA, 02114, United States
| | - Marco Zanon
- Centro Studi e Ricerche in Neuroscienze Cognitive, Dipartimento di Psicologia "Renzo Canestrari", Campus di Cesena, Alma Mater Studiorum Università di Bologna, 47521, Cesena, Italy; Neuroscience Area, International School for Advanced Studies (SISSA), 34136, Trieste, Italy
| | - Mattia Marangon
- Centro Studi e Ricerche in Neuroscienze Cognitive, Dipartimento di Psicologia "Renzo Canestrari", Campus di Cesena, Alma Mater Studiorum Università di Bologna, 47521, Cesena, Italy; Dipartimento di Neuroscienze, Biomedicina e Scienze del Movimento, Sezione di Fisiologia e Psicologia, Università di Verona, 37124, Verona, Italy
| | - Sara Borgomaneri
- Centro Studi e Ricerche in Neuroscienze Cognitive, Dipartimento di Psicologia "Renzo Canestrari", Campus di Cesena, Alma Mater Studiorum Università di Bologna, 47521, Cesena, Italy
| | - Alessio Avenanti
- Centro Studi e Ricerche in Neuroscienze Cognitive, Dipartimento di Psicologia "Renzo Canestrari", Campus di Cesena, Alma Mater Studiorum Università di Bologna, 47521, Cesena, Italy; Centro de Investigación en Neuropsicología y Neurociencias Cognitivas (CINPSI Neurocog), Universidad Católica Del Maule, 346000, Talca, Chile.
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Urbin MA, Lafe CW, Bautista ME, Wittenberg GF, Simpson TW. Effects of noninvasive neuromodulation targeting the spinal cord on early learning of force control by the digits. CNS Neurosci Ther 2024; 30:e14561. [PMID: 38421127 PMCID: PMC10851178 DOI: 10.1111/cns.14561] [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: 09/04/2023] [Revised: 11/24/2023] [Accepted: 11/28/2023] [Indexed: 03/02/2024] Open
Abstract
AIMS Control of finger forces underlies our capacity for skilled hand movements acquired during development and reacquired after neurological injury. Learning force control by the digits, therefore, predicates our functional independence. Noninvasive neuromodulation targeting synapses that link corticospinal neurons onto the final common pathway via spike-timing-dependent mechanisms can alter distal limb motor output on a transient basis, yet these effects appear subject to individual differences. Here, we investigated how this form of noninvasive neuromodulation interacts with task repetition to influence early learning of force control during precision grip. METHODS The unique effects of neuromodulation, task repetition, and neuromodulation coinciding with task repetition were tested in three separate conditions using a within-subject, cross-over design (n = 23). RESULTS We found that synchronizing depolarization events within milliseconds of stabilizing precision grip accelerated learning but only after accounting for individual differences through inclusion of subjects who showed upregulated corticospinal excitability at 2 of 3 time points following conditioning stimulation (n = 19). CONCLUSIONS Our findings provide insights into how the state of the corticospinal system can be leveraged to drive early motor skill learning, further emphasizing individual differences in the response to noninvasive neuromodulation. We interpret these findings in the context of biological mechanisms underlying the observed effects and implications for emerging therapeutic applications.
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Affiliation(s)
- Michael A. Urbin
- Human Engineering Research Laboratories, VA RR&D Center of ExcellenceVA Pittsburgh Healthcare SystemPittsburghPennsylvaniaUSA
| | - Charley W. Lafe
- Human Engineering Research Laboratories, VA RR&D Center of ExcellenceVA Pittsburgh Healthcare SystemPittsburghPennsylvaniaUSA
| | - Manuel E. Bautista
- Human Engineering Research Laboratories, VA RR&D Center of ExcellenceVA Pittsburgh Healthcare SystemPittsburghPennsylvaniaUSA
| | - George F. Wittenberg
- Human Engineering Research Laboratories, VA RR&D Center of ExcellenceVA Pittsburgh Healthcare SystemPittsburghPennsylvaniaUSA
- Department of NeurologyUniversity of PittsburghPittsburghPennsylvaniaUSA
- Rehabilitation Neural Engineering Laboratories, Department of Physical Medicine & RehabilitationUniversity of PittsburghPittsburghPennsylvaniaUSA
| | - Tyler W. Simpson
- Rehabilitation Neural Engineering Laboratories, Department of Physical Medicine & RehabilitationUniversity of PittsburghPittsburghPennsylvaniaUSA
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Mattioli F, Maglianella V, D'Antonio S, Trimarco E, Caligiore D. Non-invasive brain stimulation for patients and healthy subjects: Current challenges and future perspectives. J Neurol Sci 2024; 456:122825. [PMID: 38103417 DOI: 10.1016/j.jns.2023.122825] [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: 07/06/2023] [Revised: 11/22/2023] [Accepted: 11/28/2023] [Indexed: 12/19/2023]
Abstract
Non-invasive brain stimulation (NIBS) techniques have a rich historical background, yet their utilization has witnessed significant growth only recently. These techniques encompass transcranial electrical stimulation and transcranial magnetic stimulation, which were initially employed in neuroscience to explore the intricate relationship between the brain and behaviour. However, they are increasingly finding application in research contexts as a means to address various neurological, psychiatric, and neurodegenerative disorders. This article aims to fulfill two primary objectives. Firstly, it seeks to showcase the current state of the art in the clinical application of NIBS, highlighting how it can improve and complement existing treatments. Secondly, it provides a comprehensive overview of the utilization of NIBS in augmenting the brain function of healthy individuals, thereby enhancing their performance. Furthermore, the article delves into the points of convergence and divergence between these two techniques. It also addresses the existing challenges and future prospects associated with NIBS from ethical and research standpoints.
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Affiliation(s)
- Francesco Mattioli
- AI2Life s.r.l., Innovative Start-Up, ISTC-CNR Spin-Off, Via Sebino 32, 00199 Rome, Italy; School of Computing, Electronics and Mathematics, University of Plymouth, Drake Circus, Plymouth PL4 8AA, United Kingdom
| | - Valerio Maglianella
- Computational and Translational Neuroscience Laboratory, Institute of Cognitive Sciences and Technologies, National Research Council (CTNLab-ISTC-CNR), Via San Martino della Battaglia 44, 00185 Rome, Italy
| | - Sara D'Antonio
- Computational and Translational Neuroscience Laboratory, Institute of Cognitive Sciences and Technologies, National Research Council (CTNLab-ISTC-CNR), Via San Martino della Battaglia 44, 00185 Rome, Italy
| | - Emiliano Trimarco
- Computational and Translational Neuroscience Laboratory, Institute of Cognitive Sciences and Technologies, National Research Council (CTNLab-ISTC-CNR), Via San Martino della Battaglia 44, 00185 Rome, Italy
| | - Daniele Caligiore
- AI2Life s.r.l., Innovative Start-Up, ISTC-CNR Spin-Off, Via Sebino 32, 00199 Rome, Italy; Computational and Translational Neuroscience Laboratory, Institute of Cognitive Sciences and Technologies, National Research Council (CTNLab-ISTC-CNR), Via San Martino della Battaglia 44, 00185 Rome, Italy.
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Moreno-Roco J, del Valle L, Jiménez D, Acosta I, Castillo JL, Dharmadasa T, Kiernan MC, Matamala JM. Diagnostic utility of transcranial magnetic stimulation for neurodegenerative disease: a critical review. Dement Neuropsychol 2024; 17:e20230048. [PMID: 38189033 PMCID: PMC10768644 DOI: 10.1590/1980-5764-dn-2023-0048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 09/13/2023] [Accepted: 09/24/2023] [Indexed: 01/09/2024] Open
Abstract
Neurodegenerative diseases pose significant challenges due to their impact on brain structure, function, and cognition. As life expectancy rises, the prevalence of these disorders is rapidly increasing, resulting in substantial personal, familial, and societal burdens. Efforts have been made to optimize the diagnostic and therapeutic processes, primarily focusing on clinical, cognitive, and imaging characterization. However, the emergence of non-invasive brain stimulation techniques, specifically transcranial magnetic stimulation (TMS), offers unique functional insights and diagnostic potential. TMS allows direct evaluation of brain function, providing valuable information inaccessible through other methods. This review aims to summarize the current and potential diagnostic utility of TMS in investigating neurodegenerative diseases, highlighting its relevance to the field of cognitive neuroscience. The findings presented herein contribute to the growing body of research focused on improving our understanding and management of these debilitating conditions, particularly in regions with limited resources and a pressing need for innovative approaches.
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Affiliation(s)
- Javier Moreno-Roco
- Universidad de Chile, Facultad de Medicina, Laboratorio de Neurología y Neurofisiología Traslacional, Santiago, Chile
- Universidad de Chile, Facultad de Medicina, Centro de Investigación Clínica Avanzado (CICA) Oriente, Santiago, Chile
- Universidad de Chile, Facultad de Medicina, Departamento de Ciencias Neurológicas Oriente, Santiago, Chile
| | - Lucía del Valle
- Universidad de Chile, Facultad de Medicina, Laboratorio de Neurología y Neurofisiología Traslacional, Santiago, Chile
- Universidad de Chile, Facultad de Medicina, Centro de Investigación Clínica Avanzado (CICA) Oriente, Santiago, Chile
- Universidad de Chile, Facultad de Medicina, Departamento de Ciencias Neurológicas Oriente, Santiago, Chile
| | - Daniel Jiménez
- Universidad de Chile, Facultad de Medicina, Laboratorio de Neurología y Neurofisiología Traslacional, Santiago, Chile
- Universidad de Chile, Facultad de Medicina, Centro de Investigación Clínica Avanzado (CICA) Oriente, Santiago, Chile
- Universidad de Chile, Facultad de Medicina, Departamento de Ciencias Neurológicas Oriente, Santiago, Chile
- Hospital del Salvador, Servicio de Neurología, Santiago, Chile
| | - Ignacio Acosta
- Universidad de Chile, Facultad de Medicina, Laboratorio de Neurología y Neurofisiología Traslacional, Santiago, Chile
- Universidad de Chile, Facultad de Medicina, Centro de Investigación Clínica Avanzado (CICA) Oriente, Santiago, Chile
- Universidad de Chile, Facultad de Medicina, Departamento de Ciencias Neurológicas Oriente, Santiago, Chile
- Hospital del Salvador, Servicio de Neurología, Santiago, Chile
| | - José Luis Castillo
- Universidad de Chile, Facultad de Medicina, Laboratorio de Neurología y Neurofisiología Traslacional, Santiago, Chile
- Universidad de Chile, Facultad de Medicina, Departamento de Ciencias Neurológicas Oriente, Santiago, Chile
| | - Thanuja Dharmadasa
- University of Melbourne, The Florey Institute of Neuroscience and Mental Health, Parkville, Victoria, Australia
- The Royal Melbourne Hospital, Department of Neurology, Parkville, Victoria, Australia
- University of Sydney, Brain and Mind Centre, Sydney, Australia
| | - Matthew C. Kiernan
- University of Sydney, Brain and Mind Centre, Sydney, Australia
- Royal Prince Alfred Hospital, Department of Neurology, Sydney, AustraliaArgento
| | - José Manuel Matamala
- Universidad de Chile, Facultad de Medicina, Laboratorio de Neurología y Neurofisiología Traslacional, Santiago, Chile
- Universidad de Chile, Facultad de Medicina, Centro de Investigación Clínica Avanzado (CICA) Oriente, Santiago, Chile
- Universidad de Chile, Facultad de Medicina, Departamento de Ciencias Neurológicas Oriente, Santiago, Chile
- Universidad de Chile, Facultad de Medicina, Departamento de Neurociencias, Santiago, Chile
- Universidad de Chile, Facultad de Medicina, Instituto de Neurociencia Biomédica (BNI), Santiago, Chile
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Guidali G, Bagattini C, De Matola M, Brignani D. Influence of frontal-to-parietal connectivity in pseudoneglect: A cortico-cortical paired associative stimulation study. Cortex 2023; 169:50-64. [PMID: 37862830 DOI: 10.1016/j.cortex.2023.08.012] [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: 06/09/2023] [Revised: 07/27/2023] [Accepted: 08/23/2023] [Indexed: 10/22/2023]
Abstract
Pseudoneglect is a set of visuospatial biases that entails a behavioral advantage for stimuli appearing in the left hemifield compared to the right one. Although right hemisphere dominance for visuospatial processing has been invoked to explain this phenomenon, its neurophysiological mechanisms are still debated, and the role of intra- and inter-hemispheric connectivity is yet to be defined. The present study explored the possibility of modulating pseudoneglect in healthy participants through a cortico-cortical paired associative stimulation protocol (ccPAS): a non-invasive brain stimulation protocol that manipulates the interplay between brain regions through the repeated, time-locked coupling of two transcranial magnetic stimulation (TMS) pulses. In the first experiment, healthy participants underwent a frontal-to-parietal (FP) and a parietal-to-frontal (PF) ccPAS. In the FP protocol, the first TMS pulse targeted the right frontal eye field (FEF), and the second pulse the right inferior parietal lobule (IPL), two critical areas for visuospatial and attentional processing. In the PF condition, the order of the pulses was reversed. In both protocols, the inter-stimulus interval (ISI) was 10 ms. Before and after stimulation, pseudoneglect was assessed with a landmark task and a manual line bisection task. A second experiment controlled for ccPAS timing dependency by testing FP-ccPAS with a longer ISI of 100 ms. Results showed that after administering the FP-ccPAS with the ISI of 10 ms, participants' leftward bias in the landmark task increased significantly, with no effects in the manual line bisection task. The other two protocols tested were ineffective. Our findings showed that ccPAS could be used to modulate pseudoneglect by exploiting frontal-to-parietal connectivity, possibly through increased top-down attentional control. FP-ccPAS could represent a promising tool to investigate connectivity properties within visuospatial and attentional networks in the healthy and as a potential rehabilitation protocol in patients suffering from severe visuospatial pathologies.
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Affiliation(s)
- Giacomo Guidali
- Neurophysiology Lab, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy.
| | - Chiara Bagattini
- Section of Neurosurgery, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Matteo De Matola
- Neurophysiology Lab, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy
| | - Debora Brignani
- Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy.
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Pillen S, Shulga A, Zrenner C, Ziemann U, Bergmann TO. Repetitive sensorimotor mu-alpha phase-targeted afferent stimulation produces no phase-dependent plasticity related changes in somatosensory evoked potentials or sensory thresholds. PLoS One 2023; 18:e0293546. [PMID: 37903116 PMCID: PMC10615264 DOI: 10.1371/journal.pone.0293546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 10/13/2023] [Indexed: 11/01/2023] Open
Abstract
Phase-dependent plasticity has been proposed as a neurobiological mechanism by which oscillatory phase-amplitude cross-frequency coupling mediates memory process in the brain. Mimicking this mechanism, real-time EEG oscillatory phase-triggered transcranial magnetic stimulation (TMS) has successfully induced LTP-like changes in corticospinal excitability in the human motor cortex. Here we asked whether EEG phase-triggered afferent stimulation alone, if repetitively applied to the peaks, troughs, or random phases of the sensorimotor mu-alpha rhythm, would be sufficient to modulate the strength of thalamocortical synapses as assessed by changes in somatosensory evoked potential (SEP) N20 and P25 amplitudes and sensory thresholds (ST). Specifically, we applied 100 Hz triplets of peripheral electrical stimulation (PES) to the thumb, middle, and little finger of the right hand in pseudorandomized trials, with the afferent input from each finger repetitively and consistently arriving either during the cortical mu-alpha trough or peak or at random phases. No significant changes in SEP amplitudes or ST were observed across the phase-dependent PES intervention. We discuss potential limitations of the study and argue that suboptimal stimulation parameter choices rather than a general lack of phase-dependent plasticity in thalamocortical synapses are responsible for this null finding. Future studies should further explore the possibility of phase-dependent sensory stimulation.
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Affiliation(s)
- Steven Pillen
- Department of Neurology & Stroke, Eberhard Karls University of Tübingen, Tübingen, Germany
- Hertie Institute for Clinical Brain Research, Eberhard Karls University of Tübingen, Tübingen, Germany
- Neuroimaging Center, Focus Program Translational Neuroscience, Johannes Gutenberg University Medical Center, Mainz, Germany
- Leibniz Institute for Resilience Research, Mainz, Germany
| | - Anastasia Shulga
- Ward for Demanding Rehabilitation, Helsinki University Hospital, Department of Physical and Rehabilitation Medicine, Helsinki, Finland
- BioMag Laboratory, Helsinki University Hospital Medical Imaging Center, Helsinki, Finland
| | - Christoph Zrenner
- Department of Neurology & Stroke, Eberhard Karls University of Tübingen, Tübingen, Germany
- Hertie Institute for Clinical Brain Research, Eberhard Karls University of Tübingen, Tübingen, Germany
- Temerty Centre for Therapeutic Brain Intervention, Centre for Addiction and Mental Health, and Department of Psychiatry, University of Toronto, Toronto, ON, Canada
- Institute for Biomedical Engineering, University of Toronto, Toronto, ON, Canada
| | - Ulf Ziemann
- Department of Neurology & Stroke, Eberhard Karls University of Tübingen, Tübingen, Germany
- Hertie Institute for Clinical Brain Research, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Til Ole Bergmann
- Department of Neurology & Stroke, Eberhard Karls University of Tübingen, Tübingen, Germany
- Hertie Institute for Clinical Brain Research, Eberhard Karls University of Tübingen, Tübingen, Germany
- Neuroimaging Center, Focus Program Translational Neuroscience, Johannes Gutenberg University Medical Center, Mainz, Germany
- Leibniz Institute for Resilience Research, Mainz, Germany
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9
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Hernandez-Pavon JC, San Agustín A, Wang MC, Veniero D, Pons JL. Can we manipulate brain connectivity? A systematic review of cortico-cortical paired associative stimulation effects. Clin Neurophysiol 2023; 154:169-193. [PMID: 37634335 DOI: 10.1016/j.clinph.2023.06.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 05/09/2023] [Accepted: 06/16/2023] [Indexed: 08/29/2023]
Abstract
OBJECTIVE Cortico-cortical paired associative stimulation (ccPAS) is a form of dual-site transcranial magnetic stimulation (TMS) entailing a series of single-TMS pulses paired at specific interstimulus intervals (ISI) delivered to distant cortical areas. The goal of this article is to systematically review its efficacy in inducing plasticity in humans focusing on stimulation parameters and hypotheses of underlying neurophysiology. METHODS A systematic review of the literature from 2009-2023 was undertaken to identify all articles utilizing ccPAS to study brain plasticity and connectivity. Six electronic databases were searched and included. RESULTS 32 studies were identified. The studies targeted connections within the same hemisphere or between hemispheres. 28 ccPAS studies were in healthy participants, 1 study in schizophrenia, and 1 in Alzheimer's disease (AD) patients. 2 additional studies used cortico-cortical repetitive paired associative stimulation (cc-rPAS) in generalized anxiety disorder (GAD) patients. Outcome measures include electromyography (EMG), behavioral measures, electroencephalography (EEG), and functional magnetic resonance imaging (fMRI). ccPAS seems to be able to modulate brain connectivity depending on the ISI. CONCLUSIONS ccPAS can be used to modulate corticospinal excitability, brain activity, and behavior. Although the stimulation parameters used across studies reviewed in this paper are varied, ccPAS is a promising approach for basic research and potential clinical applications. SIGNIFICANCE Recent advances in neuroscience have caused a shift of interest from the study of single areas to a more complex approach focusing on networks of areas that orchestrate brain activity. Consequently, the TMS community is also witnessing a change, with a growing interest in targeting multiple brain areas rather than a single locus, as evidenced by an increasing number of papers using ccPAS. In light of this new enthusiasm for brain connectivity, this review summarizes existing literature and stimulation parameters that have proven effective in changing electrophysiological, behavioral, or neuroimaging-derived measures.
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Affiliation(s)
- Julio C Hernandez-Pavon
- Legs + Walking Lab, Shirley Ryan AbilityLab (Formerly, The Rehabilitation Institute of Chicago), Chicago, IL, USA; Center for Brain Stimulation, Shirley Ryan AbilityLab, Chicago, IL, USA; Department of Physical Medicine and Rehabilitation, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; Department of Psychological Sciences, Kansas State University, Manhattan, KS, USA.
| | - Arantzazu San Agustín
- Legs + Walking Lab, Shirley Ryan AbilityLab (Formerly, The Rehabilitation Institute of Chicago), Chicago, IL, USA; Center for Brain Stimulation, Shirley Ryan AbilityLab, Chicago, IL, USA; Department of Physical Medicine and Rehabilitation, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; Neural Rehabilitation Group, Cajal Institute, CSIC, Madrid, Spain; PhD Program in Neuroscience, Autonoma de Madrid University-Cajal Institute, Madrid 28029, Spain
| | - Max C Wang
- Department of Physical Therapy and Human Movement Science, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | | | - Jose L Pons
- Legs + Walking Lab, Shirley Ryan AbilityLab (Formerly, The Rehabilitation Institute of Chicago), Chicago, IL, USA; Center for Brain Stimulation, Shirley Ryan AbilityLab, Chicago, IL, USA; Department of Physical Medicine and Rehabilitation, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Chicago, IL, USA
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Asci F, Di Stefano G, Di Santo A, Bianchini E, Leone C, La Cesa S, Zampogna A, Cruccu G, Suppa A. Pain-motor integration in chronic pain: A neurophysiological study. Clin Neurophysiol 2023; 154:107-115. [PMID: 37595480 DOI: 10.1016/j.clinph.2023.07.010] [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: 04/04/2023] [Revised: 06/22/2023] [Accepted: 07/18/2023] [Indexed: 08/20/2023]
Abstract
OBJECTIVE Chronic pain may lead to functional changes in several brain regions, including the primary motor cortex (M1). Our neurophysiological study aimed to probe M1 plasticity, through a non-invasive transcranial magnetic stimulation protocol, in a cohort of patients with chronic pain. METHODS Twenty patients with chronic pain (age ± SD: 62.9 ± 9.9) and 20 age- and sex-matched healthy controls (age ± SD: 59.6 ± 15.8) were recruited. Standardized scales were used for the evaluation of pain severity. Neurophysiological measures included laser-evoked potentials (LEPs) and motor-evoked potentials (MEPs) collected at baseline and over 60 minutes following a standardized Laser-paired associative stimulation (Laser-PAS) protocol. RESULTS LEPs and MEPs were comparable in patients with chronic pain and controls. The pain threshold was lower in patients than in controls. Laser-PAS elicited decreased responses in patients with chronic pain. The response to Laser-PAS was similar in subgroups of patients with different chronic pain phenotypes. CONCLUSIONS M1 plasticity, as tested by Laser-PAS, is altered in patients with chronic pain, possibly reflecting abnormal pain-motor integration processes. SIGNIFICANCE Chronic pain is associated with a disorder of M1 plasticity raising from abnormal pain-motor integration.
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Affiliation(s)
- Francesco Asci
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, 00185 Rome, Italy; IRCCS Neuromed Institute, Via Atinense, 18, 86077 Pozzilli, IS, Italy.
| | - Giulia Di Stefano
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, 00185 Rome, Italy.
| | - Alessandro Di Santo
- Unit of Neurology, Neurophysiology, Neurobiology, Department of Medicine, Università Campus Bio-Medico di Roma, Via Álvaro del Portillo 21, 00128 Rome, Italy.
| | - Edoardo Bianchini
- Department of Neuroscience, Mental Health and Sense Organs (NESMOS), Sapienza University of Rome, Via di Grottarossa 1035-1039, 00189 Rome, Italy.
| | - Caterina Leone
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, 00185 Rome, Italy.
| | - Silvia La Cesa
- Unit of Neurology, S. Camillo-Forlanini Hospital, Rome, Italy.
| | - Alessandro Zampogna
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, 00185 Rome, Italy.
| | - Giorgio Cruccu
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, 00185 Rome, Italy.
| | - Antonio Suppa
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, 00185 Rome, Italy; IRCCS Neuromed Institute, Via Atinense, 18, 86077 Pozzilli, IS, Italy.
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11
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Asci F, Falletti M, Zampogna A, Patera M, Hallett M, Rothwell J, Suppa A. Rigidity in Parkinson's disease: evidence from biomechanical and neurophysiological measures. Brain 2023; 146:3705-3718. [PMID: 37018058 PMCID: PMC10681667 DOI: 10.1093/brain/awad114] [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: 10/14/2022] [Revised: 03/14/2023] [Accepted: 03/23/2023] [Indexed: 04/06/2023] Open
Abstract
Although rigidity is a cardinal motor sign in patients with Parkinson's disease (PD), the instrumental measurement of this clinical phenomenon is largely lacking, and its pathophysiological underpinning remains still unclear. Further advances in the field would require innovative methodological approaches able to measure parkinsonian rigidity objectively, discriminate the different biomechanical sources of muscle tone (neural or visco-elastic components), and finally clarify the contribution to 'objective rigidity' exerted by neurophysiological responses, which have previously been associated with this clinical sign (i.e. the long-latency stretch-induced reflex). Twenty patients with PD (67.3 ± 6.9 years) and 25 age- and sex-matched controls (66.9 ± 7.4 years) were recruited. Rigidity was measured clinically and through a robotic device. Participants underwent robot-assisted wrist extensions at seven different angular velocities randomly applied, when ON therapy. For each value of angular velocity, several biomechanical (i.e. elastic, viscous and neural components) and neurophysiological measures (i.e. short and long-latency reflex and shortening reaction) were synchronously assessed and correlated with the clinical score of rigidity (i.e. Unified Parkinson's Disease Rating Scale-part III, subitems for the upper limb). The biomechanical investigation allowed us to measure 'objective rigidity' in PD and estimate the neuronal source of this phenomenon. In patients, 'objective rigidity' progressively increased along with the rise of angular velocities during robot-assisted wrist extensions. The neurophysiological examination disclosed increased long-latency reflexes, but not short-latency reflexes nor shortening reaction, in PD compared with control subjects. Long-latency reflexes progressively increased according to angular velocities only in patients with PD. Lastly, specific biomechanical and neurophysiological abnormalities correlated with the clinical score of rigidity. 'Objective rigidity' in PD correlates with velocity-dependent abnormal neuronal activity. The observations overall (i.e. the velocity-dependent feature of biomechanical and neurophysiological measures of objective rigidity) would point to a putative subcortical network responsible for 'objective rigidity' in PD, which requires further investigation.
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Affiliation(s)
- Francesco Asci
- Department of Human Neurosciences, Sapienza University of Rome, 00185 Rome, Italy
- IRCCS Neuromed Institute, 86077 Pozzilli (IS), Italy
| | - Marco Falletti
- Department of Human Neurosciences, Sapienza University of Rome, 00185 Rome, Italy
| | - Alessandro Zampogna
- Department of Human Neurosciences, Sapienza University of Rome, 00185 Rome, Italy
| | - Martina Patera
- Department of Human Neurosciences, Sapienza University of Rome, 00185 Rome, Italy
| | - Mark Hallett
- Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20814, USA
| | - John Rothwell
- UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Antonio Suppa
- Department of Human Neurosciences, Sapienza University of Rome, 00185 Rome, Italy
- IRCCS Neuromed Institute, 86077 Pozzilli (IS), Italy
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12
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Haakana P, Holopainen K, Nätkynmäki A, Kirveskari E, Tarvainen MP, Shulga A. The effect of paired associative stimulation with a high-intensity cortical component and a high-frequency peripheral component on heart rate and heart rate variability in healthy subjects. FRONTIERS IN REHABILITATION SCIENCES 2023; 4:1200958. [PMID: 37565182 PMCID: PMC10410150 DOI: 10.3389/fresc.2023.1200958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 07/11/2023] [Indexed: 08/12/2023]
Abstract
Objective A novel protocol for paired associative stimulation (PAS), called high PAS, consists of high-intensity transcranial magnetic stimulation (TMS) and high-frequency peripheral nerve stimulation (PNS). High PAS was developed for spinal cord injury rehabilitation and targets plastic changes in stimulated pathways in the corticospinal tract, which improves motor function. As therapy interventions can last many weeks, it is important to fully understand the effects of high PAS, including its effect on the cardiovascular system. Heart rate variability (HRV) has been used to measure changes in both sympathetic and parasympathetic systems. Methods We used short-term HRV measurements to evaluate the effects of one 20-min session of high PAS on 17 healthy individuals. HRV was recorded for 5 min before (PRE), during (STIM), immediately after (POST), 30 min after (POST30), and 60 min after (POST60) the stimulation. Five participants repeated the HRV setup with sham stimulation. Results A significant decrease in low-frequency (LF) power (n.u.) (p = 0.002), low-frequency to high-frequency (HF) ratio (p = 0.017), in Poincaré plot [the standard deviation of RR intervals perpendicular to (SD1) and along (SD2) the line of identity SD2/SD1 ratio p < 0.001], and an increase in HF power (n.u.) (p = 0.002) were observed between PRE and STIM conditions; these changes were fully reversible immediately after stimulation. PRE to POST by 3% (p = 0.015) and continued to decline until POST60 by 5% (p = 0.011). LF power (ms2) (p = 0.017) and SD2 (p = 0.015) decreased from PRE to STIM and increased from PRE to POST (p = 0.025 and p = 0.017, respectively). The results from sham PAS exhibited a trend similar to active high-PAS stimulation. Conclusions High PAS does not have sustained effects during 60-min follow-up on cardiovascular functions, as measured by HRV. None of the short-term results indicates activation of the sympathetic nervous system in healthy individuals. Observed changes in HRV indicate higher parasympathetic activity during stimulation, which is reversible, and is plausibly explained by the fact that the participants spend 20 min without moving, talking, or using phones while being stimulated.
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Affiliation(s)
- P. Haakana
- BioMag Laboratory, HUS Diagnostic Center, Helsinki University Hospital, University of Helsinki and Aalto University School of Science, Helsinki, Finland
- Motion Analysis Laboratory, New Children’s Hospital, Helsinki University Hospital and University of Helsinki, Helsinki, Finland
| | - K. Holopainen
- BioMag Laboratory, HUS Diagnostic Center, Helsinki University Hospital, University of Helsinki and Aalto University School of Science, Helsinki, Finland
| | - A. Nätkynmäki
- BioMag Laboratory, HUS Diagnostic Center, Helsinki University Hospital, University of Helsinki and Aalto University School of Science, Helsinki, Finland
| | - E. Kirveskari
- BioMag Laboratory, HUS Diagnostic Center, Helsinki University Hospital, University of Helsinki and Aalto University School of Science, Helsinki, Finland
- HUS Medical Imaging Center, Clinical Neurophysiology, Clinical Neurosciences, Helsinki University Hospital and University of Helsinki, Helsinki, Finland
| | - M. P. Tarvainen
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
- Department of Clinical Physiology and Nuclear Medicine, Kuopio University Hospital, Kuopio, Finland
| | - A. Shulga
- BioMag Laboratory, HUS Diagnostic Center, Helsinki University Hospital, University of Helsinki and Aalto University School of Science, Helsinki, Finland
- Department of Physical and Rehabilitation Medicine, Helsinki University Hospital and University of Helsinki, Helsinki, Finland
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Costanzo M, Leodori G, Cutrona C, Marchet F, De Bartolo MI, Mancuso M, Belvisi D, Conte A, Berardelli A, Fabbrini G. Motor Cortical Correlates of Paired Associative Stimulation Induced Plasticity: A TMS-EEG Study. Brain Sci 2023; 13:921. [PMID: 37371399 DOI: 10.3390/brainsci13060921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Revised: 05/31/2023] [Accepted: 06/05/2023] [Indexed: 06/29/2023] Open
Abstract
Paired associative stimulation (PAS) is a non-invasive brain stimulation technique that modulates synaptic plasticity in the human motor cortex (M1). Since previous studies have primarily used motor-evoked potentials (MEPs) as outcome measure, cortical correlates of PAS-induced plasticity remain unknown. Therefore, the aim of this observational study was to investigate cortical correlates of a standard PAS induced plasticity in the primary motor cortex by using a combined TMS-EEG approach in a cohort of eighteen healthy subjects. In addition to the expected long-lasting facilitatory modulation of MEPs amplitude, PAS intervention also induced a significant increase in transcranial magnetic stimulation-evoked potentials (TEPs) P30 and P60 amplitude. No significant correlation between the magnitude of PAS-induced changes in TEP components and MEP amplitude were observed. However, the linear regression analysis revealed that the combined changes in P30 and P60 component amplitudes significantly predicted the MEP facilitation after PAS. The findings of our study offer novel insight into the neurophysiological changes associated with PAS-induced plasticity at M1 cortical level and suggest a complex relationship between TEPs and MEPs changes following PAS.
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Affiliation(s)
| | - Giorgio Leodori
- IRCCS Neuromed, 86077 Pozzilli, Italy
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università 30, 00185 Rome, Italy
| | | | - Francesco Marchet
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università 30, 00185 Rome, Italy
| | | | - Marco Mancuso
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università 30, 00185 Rome, Italy
| | - Daniele Belvisi
- IRCCS Neuromed, 86077 Pozzilli, Italy
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università 30, 00185 Rome, Italy
| | - Antonella Conte
- IRCCS Neuromed, 86077 Pozzilli, Italy
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università 30, 00185 Rome, Italy
| | - Alfredo Berardelli
- IRCCS Neuromed, 86077 Pozzilli, Italy
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università 30, 00185 Rome, Italy
| | - Giovanni Fabbrini
- IRCCS Neuromed, 86077 Pozzilli, Italy
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università 30, 00185 Rome, Italy
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14
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Hernandez-Pavon JC, Schneider-Garces N, Begnoche JP, Miller LE, Raij T. Targeted Modulation of Human Brain Interregional Effective Connectivity With Spike-Timing Dependent Plasticity. Neuromodulation 2023; 26:745-754. [PMID: 36404214 PMCID: PMC10188658 DOI: 10.1016/j.neurom.2022.10.045] [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: 06/15/2022] [Revised: 09/23/2022] [Accepted: 10/04/2022] [Indexed: 11/19/2022]
Abstract
OBJECTIVE The ability to selectively up- or downregulate interregional brain connectivity would be useful for research and clinical purposes. Toward this aim, cortico-cortical paired associative stimulation (ccPAS) protocols have been developed in which two areas are repeatedly stimulated with a millisecond-level asynchrony. However, ccPAS results in humans using bifocal transcranial magnetic stimulation (TMS) have been variable, and the mechanisms remain unproven. In this study, our goal was to test whether ccPAS mechanism is spike-timing-dependent plasticity (STDP). MATERIALS AND METHODS Eleven healthy participants received ccPAS to the left primary motor cortex (M1) → right M1 with three different asynchronies (5 milliseconds shorter, equal to, or 5 milliseconds longer than the 9-millisecond transcallosal conduction delay) in separate sessions. To observe the neurophysiological effects, single-pulse TMS was delivered to the left M1 before and after ccPAS while cortico-cortical evoked responses were extracted from the contralateral M1 using source-resolved electroencephalography. RESULTS Consistent with STDP mechanisms, the effects on synaptic strengths flipped depending on the asynchrony. Further implicating STDP, control experiments suggested that the effects were unidirectional and selective to the targeted connection. CONCLUSION The results support the idea that ccPAS induces STDP and may selectively up- or downregulate effective connectivity between targeted regions in the human brain.
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Affiliation(s)
- Julio C Hernandez-Pavon
- Department of Physical Medicine and Rehabilitation, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; Center for Brain Stimulation, Shirley Ryan AbilityLab, Chicago, IL, USA; Legs + Walking Lab, Shirley Ryan AbilityLab, Chicago, IL, USA
| | | | | | - Lee E Miller
- Department of Physical Medicine and Rehabilitation, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL, USA; Limb Motor Control Lab, Shirley Ryan AbilityLab, Chicago, IL, USA
| | - Tommi Raij
- Department of Physical Medicine and Rehabilitation, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; Center for Brain Stimulation, Shirley Ryan AbilityLab, Chicago, IL, USA; Department of Neurobiology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL, USA.
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15
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Turrini S, Fiori F, Chiappini E, Lucero B, Santarnecchi E, Avenanti A. Cortico-cortical paired associative stimulation (ccPAS) over premotor-motor areas affects local circuitries in the human motor cortex via Hebbian plasticity. Neuroimage 2023; 271:120027. [PMID: 36925088 DOI: 10.1016/j.neuroimage.2023.120027] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 03/09/2023] [Accepted: 03/13/2023] [Indexed: 03/17/2023] Open
Abstract
Transcranial magnetic stimulation (TMS) studies have shown that cortico-cortical paired associative stimulation (ccPAS) can strengthen connectivity between the ventral premotor cortex (PMv) and the primary motor cortex (M1) by modulating convergent input over M1 via Hebbian spike-timing-dependent plasticity (STDP). However, whether ccPAS locally affects M1 activity remains unclear. We tested 60 right-handed young healthy humans in two studies, using a combination of dual coil TMS and ccPAS over the left PMv and M1 to probe and manipulate PMv-to-M1 connectivity, and single- and paired-pulse TMS to assess neural activity within M1. We provide convergent evidence that ccPAS, relying on repeated activations of excitatory PMv-to-M1 connections, acts locally over M1. During ccPAS, motor-evoked potentials (MEPs) induced by paired PMv-M1 stimulation gradually increased. Following ccPAS, the threshold for inducing MEPs of different amplitudes decreased, and the input-output curve (IO) slope increased, highlighting increased M1 corticospinal excitability. Moreover, ccPAS reduced the magnitude of short-interval intracortical inhibition (SICI), reflecting suppression of GABA-ergic interneuronal mechanisms within M1, without affecting intracortical facilitation (ICF). These changes were specific to ccPAS Hebbian strengthening of PMv-to-M1 connectivity, as no modulations were observed when reversing the order of the PMv-M1 stimulation during a control ccPAS protocol. These findings expand prior ccPAS research that focused on the malleability of cortico-cortical connectivity at the network-level, and highlight local changes in the area of convergent activation (i.e., M1) during plasticity induction. These findings provide new mechanistic insights into the physiological basis of ccPAS that are relevant for protocol optimization.
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Affiliation(s)
- Sonia Turrini
- Centro studi e Ricerche in Neuroscienze Cognitive, Dipartimento di Psicologia "Renzo Canestrari", Alma Mater Studiorum Università di Bologna, Cesena Campus, Cesena 47521, Italy; Precision Neuroscience & Neuromodulation Program, Gordon Center for Medical Imaging, Massachusetts General Hospital & Harvard Medical School, Boston, MA 02114, United States.
| | - Francesca Fiori
- Centro studi e Ricerche in Neuroscienze Cognitive, Dipartimento di Psicologia "Renzo Canestrari", Alma Mater Studiorum Università di Bologna, Cesena Campus, Cesena 47521, Italy; NeXT: Neurophysiology and Neuro-Engineering of Human-Technology Interaction Research Unit, Campus Bio-Medico University, Rome 00128, Italy
| | - Emilio Chiappini
- Centro studi e Ricerche in Neuroscienze Cognitive, Dipartimento di Psicologia "Renzo Canestrari", Alma Mater Studiorum Università di Bologna, Cesena Campus, Cesena 47521, Italy; Institut für Klinische und Gesundheitspsychologie, Universität Wien, Vienna 1010, Austria
| | - Boris Lucero
- Centro de Investigación en Neuropsicología y Neurociencias Cognitivas (CINPSI Neurocog), Universidad Católica Del Maule, Talca 346000, Chile
| | - Emiliano Santarnecchi
- Precision Neuroscience & Neuromodulation Program, Gordon Center for Medical Imaging, Massachusetts General Hospital & Harvard Medical School, Boston, MA 02114, United States
| | - Alessio Avenanti
- Centro studi e Ricerche in Neuroscienze Cognitive, Dipartimento di Psicologia "Renzo Canestrari", Alma Mater Studiorum Università di Bologna, Cesena Campus, Cesena 47521, Italy; Centro de Investigación en Neuropsicología y Neurociencias Cognitivas (CINPSI Neurocog), Universidad Católica Del Maule, Talca 346000, Chile.
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16
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Li KP, Wu JJ, Zhou ZL, Xu DS, Zheng MX, Hua XY, Xu JG. Noninvasive Brain Stimulation for Neurorehabilitation in Post-Stroke Patients. Brain Sci 2023; 13:brainsci13030451. [PMID: 36979261 PMCID: PMC10046557 DOI: 10.3390/brainsci13030451] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 02/26/2023] [Accepted: 02/27/2023] [Indexed: 03/09/2023] Open
Abstract
Characterized by high morbidity, mortality, and disability, stroke usually causes symptoms of cerebral hypoxia due to a sudden blockage or rupture of brain vessels, and it seriously threatens human life and health. Rehabilitation is the essential treatment for post-stroke patients suffering from functional impairments, through which hemiparesis, aphasia, dysphagia, unilateral neglect, depression, and cognitive dysfunction can be restored to various degrees. Noninvasive brain stimulation (NIBS) is a popular neuromodulatory technology of rehabilitation focusing on the local cerebral cortex, which can improve clinical functions by regulating the excitability of corresponding neurons. Increasing evidence has been obtained from the clinical application of NIBS, especially repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS). However, without a standardized protocol, existing studies on NIBS show a wide variation in terms of stimulation site, frequency, intensity, dosage, and other parameters. Its application for neurorehabilitation in post-stroke patients is still limited. With advances in neuronavigation technologies, functional near-infrared spectroscopy, and functional MRI, specific brain regions can be precisely located for stimulation. On the basis of our further understanding on neural circuits, neuromodulation in post-stroke rehabilitation has also evolved from single-target stimulation to co-stimulation of two or more targets, even circuits and the network. The present study aims to review the findings of current research, discuss future directions of NIBS application, and finally promote the use of NIBS in post-stroke rehabilitation.
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Affiliation(s)
- Kun-Peng Li
- School of Rehabilitation Science, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - Jia-Jia Wu
- Center of Rehabilitation Medicine, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 200437, China
| | - Zong-Lei Zhou
- Department of Epidemiology, School of Public Health, Fudan University, Shanghai 200032, China
| | - Dong-Sheng Xu
- School of Rehabilitation Science, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - Mou-Xiong Zheng
- Department of Traumatology and Orthopedics, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 200437, China
- Correspondence: (M.-X.Z.); (X.-Y.H.); (J.-G.X.)
| | - Xu-Yun Hua
- Department of Traumatology and Orthopedics, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 200437, China
- Correspondence: (M.-X.Z.); (X.-Y.H.); (J.-G.X.)
| | - Jian-Guang Xu
- School of Rehabilitation Science, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
- Engineering Research Center of Traditional Chinese Medicine Intelligent Rehabilitation, Ministry of Education, Shanghai 201203, China
- Correspondence: (M.-X.Z.); (X.-Y.H.); (J.-G.X.)
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17
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Therrien-Blanchet JM, Ferland MC, Badri M, Rousseau MA, Merabtine A, Boucher E, Hofmann LH, Lepage JF, Théoret H. The neurophysiological aftereffects of brain stimulation in human primary motor cortex: a Sham-controlled comparison of three protocols. Cereb Cortex 2023:7030623. [PMID: 36749004 DOI: 10.1093/cercor/bhad021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 01/14/2023] [Accepted: 01/15/2023] [Indexed: 02/08/2023] Open
Abstract
Paired associative stimulation (PAS), transcranial direct current stimulation (tDCS), and transcranial alternating current stimulation (tACS) are non-invasive brain stimulation methods that are used to modulate cortical excitability. Whether one technique is superior to the others in achieving this outcome and whether individuals that respond to one intervention are more likely to respond to another remains largely unknown. In the present study, the neurophysiological aftereffects of three excitatory neurostimulation protocols were measured with transcranial magnetic stimulation (TMS). Twenty minutes of PAS at an ISI of 25 ms, anodal tDCS, 20-Hz tACS, and Sham stimulation were administered to 31 healthy adults in a repeated measures design. Compared with Sham, none of the stimulation protocols significantly modulated corticospinal excitability (input/ouput curve and slope, TMS stimulator intensity required to elicit MEPs of 1-mV amplitude) or intracortical excitability (short- and long-interval intracortical inhibition, intracortical facilitation, cortical silent period). Sham-corrected responder analysis estimates showed that an average of 41 (PAS), 39 (tDCS), and 39% (tACS) of participants responded to the interventions with an increase in corticospinal excitability. The present data show that three stimulation protocols believed to increase cortical excitability are associated with highly heterogenous and variable aftereffects that may explain a lack of significant group effects.
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Affiliation(s)
| | | | - Meriem Badri
- Département de psychologie, Université de Montréal, Montréal, QC H3C 3J7, Canada
| | | | - Amira Merabtine
- Département de psychologie, Université de Montréal, Montréal, QC H3C 3J7, Canada
| | - Emelie Boucher
- Département de psychologie, Université de Montréal, Montréal, QC H3C 3J7, Canada
| | - Lydia Helena Hofmann
- Department of Psychology and Neuroscience, Maastricht University, Maastricht 6229, The Netherlands
| | - Jean-François Lepage
- Département de Pédiatrie, Faculté de Médecine et des Sciences de la Santé de l'Université de Sherbrooke, Centre de Recherche du CHU Sherbrooke, Sherbrooke, QC J1H 5N4, Canada
| | - Hugo Théoret
- Département de psychologie, Université de Montréal, Montréal, QC H3C 3J7, Canada
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Dorrian RM, Berryman CF, Lauto A, Leonard AV. Electrical stimulation for the treatment of spinal cord injuries: A review of the cellular and molecular mechanisms that drive functional improvements. Front Cell Neurosci 2023; 17:1095259. [PMID: 36816852 PMCID: PMC9936196 DOI: 10.3389/fncel.2023.1095259] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 01/16/2023] [Indexed: 02/05/2023] Open
Abstract
Spinal cord injury (SCI) is a devastating condition that causes severe loss of motor, sensory and autonomic functions. Additionally, many individuals experience chronic neuropathic pain that is often refractory to interventions. While treatment options to improve outcomes for individuals with SCI remain limited, significant research efforts in the field of electrical stimulation have made promising advancements. Epidural electrical stimulation, peripheral nerve stimulation, and functional electrical stimulation have shown promising improvements for individuals with SCI, ranging from complete weight-bearing locomotion to the recovery of sexual function. Despite this, there is a paucity of mechanistic understanding, limiting our ability to optimize stimulation devices and parameters, or utilize combinatorial treatments to maximize efficacy. This review provides a background into SCI pathophysiology and electrical stimulation methods, before exploring cellular and molecular mechanisms suggested in the literature. We highlight several key mechanisms that contribute to functional improvements from electrical stimulation, identify gaps in current knowledge and highlight potential research avenues for future studies.
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Affiliation(s)
- Ryan M. Dorrian
- Spinal Cord Injury Research Group, School of Biomedicine, The University of Adelaide, Adelaide, SA, Australia,*Correspondence: Ryan M. Dorrian,
| | | | - Antonio Lauto
- School of Science, Western Sydney University, Penrith, NSW, Australia
| | - Anna V. Leonard
- Spinal Cord Injury Research Group, School of Biomedicine, The University of Adelaide, Adelaide, SA, Australia
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19
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Tian D, Izumi SI. TMS and neocortical neurons: an integrative review on the micro-macro connection in neuroplasticity. JAPANESE JOURNAL OF COMPREHENSIVE REHABILITATION SCIENCE 2023; 14:1-9. [PMID: 37859791 PMCID: PMC10585015 DOI: 10.11336/jjcrs.14.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/05/2022] [Indexed: 10/21/2023]
Abstract
Tian D, Izumi S. TMS and neocortical neurons: an integrative review on the micro-macro connection in neuroplasticity. Jpn J Compr Rehabil Sci 2023; 14: 1-9. Neuroplasticity plays a pivotal role in neuroscience and neurorehabilitation as it bridges the organization and reorganization properties of the brain. Among the numerous neuroplastic protocols, transcranial magnetic stimulation (TMS) is a well-established non-invasive protocol to induce plastic changes in the brain. Here, we review the findings of four plasticity-inducing TMS protocols in the human motor cortex with relatively evident mechanisms: conventional repetitive TMS (rTMS), theta-burst stimulation (TBS), quadripulse stimulation (QPS) and paired associative stimulation (PAS). Based on the reviewed evidence and a preliminary TMS neurocytological model proposed in our previous report, we further integrate the neurophysiological evidence and plasticity rules of these protocols to present an updated micro-macro connection model between neocortical neurons and the neurophysiological evidence in TMS. This prototypical model will guide further efforts to understand the neural circuit of the motor cortex, the mechanisms of TMS, and the advance of neuroplasticity technologies and their outcomes.
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Affiliation(s)
- Dongting Tian
- Department of Physical Medicine and Rehabilitation, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Shin-Ichi Izumi
- Department of Physical Medicine and Rehabilitation, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
- Tohoku University Graduate School of Biomedical Engineering, Sendai, Miyagi, Japan
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20
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Jannati A, Oberman LM, Rotenberg A, Pascual-Leone A. Assessing the mechanisms of brain plasticity by transcranial magnetic stimulation. Neuropsychopharmacology 2023; 48:191-208. [PMID: 36198876 PMCID: PMC9700722 DOI: 10.1038/s41386-022-01453-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 09/01/2022] [Accepted: 09/02/2022] [Indexed: 11/10/2022]
Abstract
Transcranial magnetic stimulation (TMS) is a non-invasive technique for focal brain stimulation based on electromagnetic induction where a fluctuating magnetic field induces a small intracranial electric current in the brain. For more than 35 years, TMS has shown promise in the diagnosis and treatment of neurological and psychiatric disorders in adults. In this review, we provide a brief introduction to the TMS technique with a focus on repetitive TMS (rTMS) protocols, particularly theta-burst stimulation (TBS), and relevant rTMS-derived metrics of brain plasticity. We then discuss the TMS-EEG technique, the use of neuronavigation in TMS, the neural substrate of TBS measures of plasticity, the inter- and intraindividual variability of those measures, effects of age and genetic factors on TBS aftereffects, and then summarize alterations of TMS-TBS measures of plasticity in major neurological and psychiatric disorders including autism spectrum disorder, schizophrenia, depression, traumatic brain injury, Alzheimer's disease, and diabetes. Finally, we discuss the translational studies of TMS-TBS measures of plasticity and their therapeutic implications.
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Affiliation(s)
- Ali Jannati
- Neuromodulation Program, Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.
- F. M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.
- Berenson-Allen Center for Noninvasive Brain Stimulation, Division of Cognitive Neurology, Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
| | - Lindsay M Oberman
- Center for Neuroscience and Regenerative Medicine, Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Alexander Rotenberg
- Neuromodulation Program, Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
- F. M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
- Berenson-Allen Center for Noninvasive Brain Stimulation, Division of Cognitive Neurology, Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Alvaro Pascual-Leone
- Department of Neurology, Harvard Medical School, Boston, MA, USA.
- Hinda and Arthur Marcus Institute for Aging Research and Deanna and Sidney Wolk Center for Memory Health, Hebrew SeniorLife, Boston, MA, USA.
- Guttmann Brain Health Institute, Institut Guttmann, Barcelona, Spain.
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21
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Pal A, Park H, Ramamurthy A, Asan AS, Bethea T, Johnkutty M, Carmel JB. Spinal cord associative plasticity improves forelimb sensorimotor function after cervical injury. Brain 2022; 145:4531-4544. [PMID: 36063483 PMCID: PMC10200304 DOI: 10.1093/brain/awac235] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 06/10/2022] [Accepted: 06/17/2022] [Indexed: 01/06/2023] Open
Abstract
Associative plasticity occurs when two stimuli converge on a common neural target. Previous efforts to promote associative plasticity have targeted cortex, with variable and moderate effects. In addition, the targeted circuits are inferred, rather than tested directly. In contrast, we sought to target the strong convergence between motor and sensory systems in the spinal cord. We developed spinal cord associative plasticity, precisely timed pairing of motor cortex and dorsal spinal cord stimulations, to target this interaction. We tested the hypothesis that properly timed paired stimulation would strengthen the sensorimotor connections in the spinal cord and improve recovery after spinal cord injury. We tested physiological effects of paired stimulation, the pathways that mediate it, and its function in a preclinical trial. Subthreshold spinal cord stimulation strongly augmented motor cortex evoked muscle potentials at the time they were paired, but only when they arrived synchronously in the spinal cord. This paired stimulation effect depended on both cortical descending motor and spinal cord proprioceptive afferents; selective inactivation of either of these pathways fully abrogated the paired stimulation effect. Spinal cord associative plasticity, repetitive pairing of these pathways for 5 or 30 min in awake rats, increased spinal excitability for hours after pairing ended. To apply spinal cord associative plasticity as therapy, we optimized the parameters to promote strong and long-lasting effects. This effect was just as strong in rats with cervical spinal cord injury as in uninjured rats, demonstrating that spared connections after moderate spinal cord injury were sufficient to support plasticity. In a blinded trial, rats received a moderate C4 contusive spinal cord injury. Ten days after injury, they were randomized to 30 min of spinal cord associative plasticity each day for 10 days or sham stimulation. Rats with spinal cord associative plasticity had significantly improved function on the primary outcome measure, a test of dexterity during manipulation of food, at 50 days after spinal cord injury. In addition, rats with spinal cord associative plasticity had persistently stronger responses to cortical and spinal stimulation than sham stimulation rats, indicating a spinal locus of plasticity. After spinal cord associative plasticity, rats had near normalization of H-reflex modulation. The groups had no difference in the rat grimace scale, a measure of pain. We conclude that spinal cord associative plasticity strengthens sensorimotor connections within the spinal cord, resulting in partial recovery of reflex modulation and forelimb function after moderate spinal cord injury. Since both motor cortex and spinal cord stimulation are performed routinely in humans, this approach can be trialled in people with spinal cord injury or other disorders that damage sensorimotor connections and impair dexterity.
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Affiliation(s)
- Ajay Pal
- Department of Orthopedics, Columbia University, New York, NY 10032, USA
| | - HongGeun Park
- Department of Orthopedics, Columbia University, New York, NY 10032, USA
| | - Aditya Ramamurthy
- Department of Orthopedics, Columbia University, New York, NY 10032, USA
| | - Ahmet S Asan
- Department of Orthopedics, Columbia University, New York, NY 10032, USA
| | - Thelma Bethea
- Department of Orthopedics, Columbia University, New York, NY 10032, USA
| | - Meenu Johnkutty
- Department of Orthopedics, Columbia University, New York, NY 10032, USA
| | - Jason B Carmel
- Department of Orthopedics, Columbia University, New York, NY 10032, USA
- Department of Neurology, Columbia University, New York, NY 10032, USA
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22
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Effective corticospinal excitability neuromodulation elicited by short-duration concurrent and synchronized associative cortical and neuromuscular stimulations. Neurosci Lett 2022; 790:136910. [DOI: 10.1016/j.neulet.2022.136910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 10/05/2022] [Accepted: 10/06/2022] [Indexed: 11/20/2022]
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23
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Cai Z, Pellegrino G, Lina J, Benali H, Grova C. Hierarchical Bayesian modeling of the relationship between task-related hemodynamic responses and cortical excitability. Hum Brain Mapp 2022; 44:876-900. [PMID: 36250709 PMCID: PMC9875942 DOI: 10.1002/hbm.26107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 09/10/2022] [Accepted: 09/18/2022] [Indexed: 01/28/2023] Open
Abstract
Investigating the relationship between task-related hemodynamic responses and cortical excitability is challenging because it requires simultaneous measurement of hemodynamic responses while applying noninvasive brain stimulation. Moreover, cortical excitability and task-related hemodynamic responses are both associated with inter-/intra-subject variability. To reliably assess such a relationship, we applied hierarchical Bayesian modeling. This study involved 16 healthy subjects who underwent simultaneous Paired Associative Stimulation (PAS10, PAS25, Sham) while monitoring brain activity using functional Near-Infrared Spectroscopy (fNIRS), targeting the primary motor cortex (M1). Cortical excitability was measured by Motor Evoked Potentials (MEPs), and the motor task-related hemodynamic responses were measured using fNIRS 3D reconstructions. We constructed three models to investigate: (1) PAS effects on the M1 excitability, (2) PAS effects on fNIRS hemodynamic responses to a finger tapping task, and (3) the correlation between PAS effects on M1 excitability and PAS effects on task-related hemodynamic responses. Significant increase in cortical excitability was found following PAS25, whereas a small reduction of the cortical excitability was shown after PAS10 and a subtle increase occurred after sham. Both HbO and HbR absolute amplitudes increased after PAS25 and decreased after PAS10. The probability of the positive correlation between modulation of cortical excitability and hemodynamic activity was 0.77 for HbO and 0.79 for HbR. We demonstrated that PAS stimulation modulates task-related cortical hemodynamic responses in addition to M1 excitability. Moreover, the positive correlation between PAS modulations of excitability and hemodynamics brought insight into understanding the fundamental properties of cortical function and cortical excitability.
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Affiliation(s)
- Zhengchen Cai
- Multimodal Functional Imaging Lab, Department of PhysicsConcordia UniversityMontréalQuébecCanada,PERFORM CentreConcordia UniversityMontréalQuébecCanada
| | - Giovanni Pellegrino
- Epilepsy Program, Schulich School of Medicine and DentistryWestern UniversityLondonOntarioCanada,Multimodal Functional Imaging Lab, Biomedical Engineering DepartmentMcGill UniversityMontréalQuébecCanada
| | - Jean‐Marc Lina
- Département de Génie ElectriqueÉcole de Technologie SupérieureMontréalQuébecCanada,Centre De Recherches En MathématiquesMontréalQuébecCanada
| | - Habib Benali
- PERFORM CentreConcordia UniversityMontréalQuébecCanada,Centre De Recherches En MathématiquesMontréalQuébecCanada,Electrical and Computer Engineering Department, Concordia UniversityMontréalCanada
| | - Christophe Grova
- Multimodal Functional Imaging Lab, Department of PhysicsConcordia UniversityMontréalQuébecCanada,PERFORM CentreConcordia UniversityMontréalQuébecCanada,Multimodal Functional Imaging Lab, Biomedical Engineering DepartmentMcGill UniversityMontréalQuébecCanada,Centre De Recherches En MathématiquesMontréalQuébecCanada
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24
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Turrini S, Fiori F, Chiappini E, Santarnecchi E, Romei V, Avenanti A. Gradual enhancement of corticomotor excitability during cortico-cortical paired associative stimulation. Sci Rep 2022; 12:14670. [PMID: 36038605 PMCID: PMC9424198 DOI: 10.1038/s41598-022-18774-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Accepted: 08/18/2022] [Indexed: 12/03/2022] Open
Abstract
Cortico-cortical paired associative stimulation (ccPAS) is an effective transcranial magnetic stimulation (TMS) method for inducing associative plasticity between interconnected brain areas in humans. Prior ccPAS studies have focused on protocol’s aftereffects. Here, we investigated physiological changes induced “online” during ccPAS administration. We tested 109 participants receiving ccPAS over left ventral premotor cortex (PMv) and primary motor cortex (M1) using a standard procedure (90 paired-pulses with 8-ms interstimulus interval, repeated at 0.1 Hz frequency). On each paired-pulse, we recorded a motor-evoked potential (MEP) to continuously trace the emergence of corticomotor changes. Participant receiving forward-ccPAS (on each pair, a first TMS pulse was administered over PMv, second over M1, i.e., PMv-to-M1) showed a gradual and linear increase in MEP size that did not reach a plateau at the end of the protocol and was greater in participants with low motor threshold. Participants receiving reverse-ccPAS (i.e., M1-to-PMv) showed a trend toward inhibition. Our study highlights the facilitatory and inhibitory modulations that occur during ccPAS administration and suggest that online MEP monitoring could provide insights into the malleability of the motor system and protocol’s effectiveness. Our findings open interesting prospects about ccPAS potential optimization in experimental and clinical settings.
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Affiliation(s)
- Sonia Turrini
- Centro Studi e Ricerche in Neuroscienze Cognitive, Dipartimento di Psicologia, Alma Mater Studiorum - Università di Bologna, Campus di Cesena. Via Rasi Spinelli 176, 47521, Cesena, Italy.,Precision Neuroscience and Neuromodulation Program, Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Francesca Fiori
- Centro Studi e Ricerche in Neuroscienze Cognitive, Dipartimento di Psicologia, Alma Mater Studiorum - Università di Bologna, Campus di Cesena. Via Rasi Spinelli 176, 47521, Cesena, Italy.,NeXT: Unità di ricerca di Neurofisiologia e Neuroingegneria dell'Interazione Uomo-Tecnologia, Università Campus Bio-Medico, Rome, Italy
| | - Emilio Chiappini
- Centro Studi e Ricerche in Neuroscienze Cognitive, Dipartimento di Psicologia, Alma Mater Studiorum - Università di Bologna, Campus di Cesena. Via Rasi Spinelli 176, 47521, Cesena, Italy.,Institut für Klinische und Gesundheitspsychologie, Universität Wien, Wien, Austria
| | - Emiliano Santarnecchi
- Precision Neuroscience and Neuromodulation Program, Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Vincenzo Romei
- Centro Studi e Ricerche in Neuroscienze Cognitive, Dipartimento di Psicologia, Alma Mater Studiorum - Università di Bologna, Campus di Cesena. Via Rasi Spinelli 176, 47521, Cesena, Italy.,IRCCS Fondazione Santa Lucia, Rome, Italy
| | - Alessio Avenanti
- Centro Studi e Ricerche in Neuroscienze Cognitive, Dipartimento di Psicologia, Alma Mater Studiorum - Università di Bologna, Campus di Cesena. Via Rasi Spinelli 176, 47521, Cesena, Italy. .,Centro de Investigación en Neuropsicología y Neurociencias Cognitivas, Universidad Católica del Maule, Talca, Chile.
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25
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Di Luzio P, Tarasi L, Silvanto J, Avenanti A, Romei V. Human perceptual and metacognitive decision-making rely on distinct brain networks. PLoS Biol 2022; 20:e3001750. [PMID: 35944012 PMCID: PMC9362930 DOI: 10.1371/journal.pbio.3001750] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 07/11/2022] [Indexed: 11/18/2022] Open
Abstract
Perceptual decisions depend on the ability to exploit available sensory information in order to select the most adaptive option from a set of alternatives. Such decisions depend on the perceptual sensitivity of the organism, which is generally accompanied by a corresponding level of certainty about the choice made. Here, by use of corticocortical paired associative transcranial magnetic stimulation protocol (ccPAS) aimed at inducing plastic changes, we shaped perceptual sensitivity and metacognitive ability in a motion discrimination task depending on the targeted network, demonstrating their functional dissociation. Neurostimulation aimed at boosting V5/MT+-to-V1/V2 back-projections enhanced motion sensitivity without impacting metacognition, whereas boosting IPS/LIP-to-V1/V2 back-projections increased metacognitive efficiency without impacting motion sensitivity. This double-dissociation provides causal evidence of distinct networks for perceptual sensitivity and metacognitive ability in humans.
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Affiliation(s)
- Paolo Di Luzio
- Center for Studies and Research in Cognitive Neuroscience, University of Bologna, Cesena, Italy
| | - Luca Tarasi
- Center for Studies and Research in Cognitive Neuroscience, University of Bologna, Cesena, Italy
| | - Juha Silvanto
- School of Psychology, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Alessio Avenanti
- Center for Studies and Research in Cognitive Neuroscience, University of Bologna, Cesena, Italy
- Centro de Investigación en Neuropsicología y Neurociencias Cognitivas, Universidad Católica del Maule, Talca, Chile
| | - Vincenzo Romei
- Center for Studies and Research in Cognitive Neuroscience, University of Bologna, Cesena, Italy
- IRCCS Fondazione Santa Lucia, Rome, Italy
- * E-mail:
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26
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Chen R, Berardelli A, Bhattacharya A, Bologna M, Chen KHS, Fasano A, Helmich RC, Hutchison WD, Kamble N, Kühn AA, Macerollo A, Neumann WJ, Pal PK, Paparella G, Suppa A, Udupa K. Clinical neurophysiology of Parkinson's disease and parkinsonism. Clin Neurophysiol Pract 2022; 7:201-227. [PMID: 35899019 PMCID: PMC9309229 DOI: 10.1016/j.cnp.2022.06.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 06/11/2022] [Accepted: 06/22/2022] [Indexed: 01/01/2023] Open
Abstract
This review is part of the series on the clinical neurophysiology of movement disorders and focuses on Parkinson’s disease and parkinsonism. The pathophysiology of cardinal parkinsonian motor symptoms and myoclonus are reviewed. The recordings from microelectrode and deep brain stimulation electrodes are reported in detail.
This review is part of the series on the clinical neurophysiology of movement disorders. It focuses on Parkinson’s disease and parkinsonism. The topics covered include the pathophysiology of tremor, rigidity and bradykinesia, balance and gait disturbance and myoclonus in Parkinson’s disease. The use of electroencephalography, electromyography, long latency reflexes, cutaneous silent period, studies of cortical excitability with single and paired transcranial magnetic stimulation, studies of plasticity, intraoperative microelectrode recordings and recording of local field potentials from deep brain stimulation, and electrocorticography are also reviewed. In addition to advancing knowledge of pathophysiology, neurophysiological studies can be useful in refining the diagnosis, localization of surgical targets, and help to develop novel therapies for Parkinson’s disease.
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Affiliation(s)
- Robert Chen
- Krembil Research Institute, University Health Network, Toronto, Ontario, Canada.,Division of Neurology, Department of Medicine, University of Toronto, Ontario, Canada.,Edmond J. Safra Program in Parkinson's Disease, Toronto Western Hospital, University Health Network, Toronto, Ontario, Canada
| | - Alfredo Berardelli
- Department of Human Neurosciences, Sapienza University of Rome, Italy.,IRCCS Neuromed Pozzilli (IS), Italy
| | - Amitabh Bhattacharya
- Department of Neurology, National Institute of Mental Health & Neurosciences (NIMHANS), Bangalore, India
| | - Matteo Bologna
- Department of Human Neurosciences, Sapienza University of Rome, Italy.,IRCCS Neuromed Pozzilli (IS), Italy
| | - Kai-Hsiang Stanley Chen
- Department of Neurology, National Taiwan University Hospital Hsinchu Branch, Hsinchu, Taiwan
| | - Alfonso Fasano
- Krembil Research Institute, University Health Network, Toronto, Ontario, Canada.,Division of Neurology, Department of Medicine, University of Toronto, Ontario, Canada.,Edmond J. Safra Program in Parkinson's Disease, Toronto Western Hospital, University Health Network, Toronto, Ontario, Canada
| | - Rick C Helmich
- Radboud University Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Department of Neurology and Centre of Expertise for Parkinson & Movement Disorders, Nijmegen, the Netherlands
| | - William D Hutchison
- Krembil Research Institute, University Health Network, Toronto, Ontario, Canada.,Departments of Surgery and Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Nitish Kamble
- Department of Neurology, National Institute of Mental Health & Neurosciences (NIMHANS), Bangalore, India
| | - Andrea A Kühn
- Department of Neurology, Movement Disorder and Neuromodulation Unit, Charité - Universitätsmedizin Berlin, Germany
| | - Antonella Macerollo
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, United Kingdom.,The Walton Centre NHS Foundation Trust for Neurology and Neurosurgery, Liverpool, United Kingdom
| | - Wolf-Julian Neumann
- Department of Neurology, Movement Disorder and Neuromodulation Unit, Charité - Universitätsmedizin Berlin, Germany
| | - Pramod Kumar Pal
- Department of Neurology, National Institute of Mental Health & Neurosciences (NIMHANS), Bangalore, India
| | | | - Antonio Suppa
- Department of Human Neurosciences, Sapienza University of Rome, Italy.,IRCCS Neuromed Pozzilli (IS), Italy
| | - Kaviraja Udupa
- Department of Neurophysiology National Institute of Mental Health & Neurosciences (NIMHANS), Bangalore, India
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27
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Samejima S, Henderson R, Pradarelli J, Mondello SE, Moritz CT. Activity-dependent plasticity and spinal cord stimulation for motor recovery following spinal cord injury. Exp Neurol 2022; 357:114178. [PMID: 35878817 DOI: 10.1016/j.expneurol.2022.114178] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 06/22/2022] [Accepted: 07/16/2022] [Indexed: 02/07/2023]
Abstract
Spinal cord injuries lead to permanent physical impairment despite most often being anatomically incomplete disruptions of the spinal cord. Remaining connections between the brain and spinal cord create the potential for inducing neural plasticity to improve sensorimotor function, even many years after injury. This narrative review provides an overview of the current evidence for spontaneous motor recovery, activity-dependent plasticity, and interventions for restoring motor control to residual brain and spinal cord networks via spinal cord stimulation. In addition to open-loop spinal cord stimulation to promote long-term neuroplasticity, we also review a more targeted approach: closed-loop stimulation. Lastly, we review mechanisms of spinal cord neuromodulation to promote sensorimotor recovery, with the goal of advancing the field of rehabilitation for physical impairments following spinal cord injury.
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Affiliation(s)
- Soshi Samejima
- International Collaboration on Repair Discoveries, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada; Department of Medicine, Division of Physical Medicine and Rehabilitation, Department of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Richard Henderson
- Department of Electrical and Computer Engineering, University of Washington, Seattle, WA, USA; Department of Rehabilitation Medicine, University of Washington, Seattle, WA, USA
| | - Jared Pradarelli
- Department of Rehabilitation Medicine, University of Washington, Seattle, WA, USA
| | - Sarah E Mondello
- Department of Rehabilitation Medicine, University of Washington, Seattle, WA, USA
| | - Chet T Moritz
- Department of Electrical and Computer Engineering, University of Washington, Seattle, WA, USA; Department of Rehabilitation Medicine, University of Washington, Seattle, WA, USA; Center for Neurotechnology, Seattle, WA, USA; Department of Physiology and Biophysics, University of Washington, Seattle, WA, USA.
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28
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Optimal peripheral nerve stimulation intensity for paired associative stimulation with high-frequency peripheral component in healthy subjects. Sci Rep 2022; 12:12466. [PMID: 35864177 PMCID: PMC9304330 DOI: 10.1038/s41598-022-16811-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 07/15/2022] [Indexed: 11/09/2022] Open
Abstract
Paired associative stimulation (PAS) with high-frequency peripheral nerve stimulation (PNS), called “high-PAS”, induces motor-evoked potential (MEP) potentiation in healthy subjects and improves muscle activity and independence in incomplete spinal cord injury patients. Data on optimal PNS intensity in PAS are scarce. In a high-PAS protocol, PNS intensity is defined as “minimal intensity required to produce F-responses”. We sought to further refine this definition and to investigate how PNS intensity affects PAS outcome. Two experiments were performed on 10 healthy subjects where MEP amplitude change was measured 0, 30, and 60 min after PAS. In the first experiment, the intensity required to achieve 7/10 persistence of F-responses was used to define PNS intensity level. In the second experiment, we used the intensity required to achieve 1/10 persistence (“baseline”). In addition, we applied this intensity at + 25%, − 25%, and − 50% levels. In the first experiment, PAS did not produce significant MEP potentiation. In the second experiment, PAS produced statistically significant MEP potentiation, with PNS intensity of “baseline” and “baseline − 25%” levels but not at + 25% or − 50% levels. In conclusion, for PAS utilizing high-frequency PNS, the intensity required to achieve 1/10 F-response persistence or the intensity 25% lower produces significant MEP potentiation in healthy subjects.
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29
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Effect of long-term paired associative stimulation on the modulation of cortical sensorimotor oscillations after spinal cord injury. Spinal Cord Ser Cases 2022; 8:38. [PMID: 35379772 PMCID: PMC8980100 DOI: 10.1038/s41394-022-00506-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 03/21/2022] [Accepted: 03/21/2022] [Indexed: 11/24/2022] Open
Abstract
Study design A prospective interventional case series. Objectives To explore changes in the modulation of cortical sensorimotor oscillations after long-term paired associative stimulation (PAS) in participants with spinal cord injury (SCI). Setting BioMag Laboratory, HUS Diagnostic Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland. Methods Five patients with chronic incomplete SCI received unilateral spinal PAS to upper limb for 16–22 days. Changes in the modulation of sensorimotor oscillations in response to tactile stimulus and active and imaginary hand movements were assessed with magnetoencephalography recorded before and after the intervention. Results PAS restored the modulation of sensorimotor oscillations in response to active hand movement in four patients, whereas the modulation following tactile stimulation remained unaltered. The observed change was larger in the hemisphere that received PAS and preceded the clinical effect of the intervention. Conclusions Long-term spinal PAS treatment, which enhances the motor functions of SCI patients, also restores the modulation of cortical sensorimotor oscillations.
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30
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Asan AS, McIntosh JR, Carmel JB. Targeting Sensory and Motor Integration for Recovery of Movement After CNS Injury. Front Neurosci 2022; 15:791824. [PMID: 35126040 PMCID: PMC8813971 DOI: 10.3389/fnins.2021.791824] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Accepted: 12/27/2021] [Indexed: 12/18/2022] Open
Abstract
The central nervous system (CNS) integrates sensory and motor information to acquire skilled movements, known as sensory-motor integration (SMI). The reciprocal interaction of the sensory and motor systems is a prerequisite for learning and performing skilled movement. Injury to various nodes of the sensorimotor network causes impairment in movement execution and learning. Stimulation methods have been developed to directly recruit the sensorimotor system and modulate neural networks to restore movement after CNS injury. Part 1 reviews the main processes and anatomical interactions responsible for SMI in health. Part 2 details the effects of injury on sites critical for SMI, including the spinal cord, cerebellum, and cerebral cortex. Finally, Part 3 reviews the application of activity-dependent plasticity in ways that specifically target integration of sensory and motor systems. Understanding of each of these components is needed to advance strategies targeting SMI to improve rehabilitation in humans after injury.
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Affiliation(s)
| | | | - Jason B. Carmel
- Departments of Neurology and Orthopedics, Columbia University, New York, NY, United States
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Suppa A, Asci F, Guerra A. Transcranial magnetic stimulation as a tool to induce and explore plasticity in humans. HANDBOOK OF CLINICAL NEUROLOGY 2022; 184:73-89. [PMID: 35034759 DOI: 10.1016/b978-0-12-819410-2.00005-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Activity-dependent synaptic plasticity is the main theoretical framework to explain mechanisms of learning and memory. Synaptic plasticity can be explored experimentally in animals through various standardized protocols for eliciting long-term potentiation and long-term depression in hippocampal and cortical slices. In humans, several non-invasive protocols of repetitive transcranial magnetic stimulation and transcranial direct current stimulation have been designed and applied to probe synaptic plasticity in the primary motor cortex, as reflected by long-term changes in motor evoked potential amplitudes. These protocols mimic those normally used in animal studies for assessing long-term potentiation and long-term depression. In this chapter, we first discuss the physiologic basis of theta-burst stimulation, paired associative stimulation, and transcranial direct current stimulation. We describe the current biophysical and theoretical models underlying the molecular mechanisms of synaptic plasticity and metaplasticity, defined as activity-dependent changes in neural functions that modulate subsequent synaptic plasticity such as long-term potentiation (LTP) and long-term depression (LTD), in the human motor cortex including calcium-dependent plasticity, spike-timing-dependent plasticity, the role of N-methyl-d-aspartate-related transmission and gamma-aminobutyric-acid interneuronal activity. We also review the putative microcircuits responsible for synaptic plasticity in the human motor cortex. We critically readdress the issue of variability in studies investigating synaptic plasticity and propose available solutions. Finally, we speculate about the utility of future studies with more advanced experimental approaches.
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Affiliation(s)
- Antonio Suppa
- Department of Human Neurosciences, Sapienza University of Rome, Rome, Italy; IRCCS Neuromed Institute, Pozzilli (IS), Italy.
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Motolese F, Capone F, Di Lazzaro V. New tools for shaping plasticity to enhance recovery after stroke. HANDBOOK OF CLINICAL NEUROLOGY 2022; 184:299-315. [PMID: 35034743 DOI: 10.1016/b978-0-12-819410-2.00016-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Stroke is the second most common cause of death worldwide and its prevalence is projected to increase in the coming years in parallel with the increase of life expectancy. Despite the great improvements in the management of the acute phase of stroke, some residual disability persists in most patients thus requiring rehabilitation. One third of patients do not reach the maximal recovery potential and different approaches have been explored with the aim to boost up recovery. In this regard, noninvasive brain stimulation techniques have been widely used to induce neuroplasticity phenomena. Different protocols of repetitive transcranial magnetic stimulation (rTMS) and transcranial electrical stimulation (tES) can induce short- and long-term changes of synaptic excitability and are promising tools for enhancing recovery in stroke patients. New options for neuromodulation are currently under investigation. They include: vagal nerve stimulation (VNS) that can be delivered invasively, with implanted stimulators and noninvasively with transcutaneous VNS (tVNS); and extremely low-frequency (1-300Hz) magnetic fields. This chapter will provide an overview on the new techniques that are used for neuroprotection and for enhancing recovery after stroke.
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Affiliation(s)
- Francesco Motolese
- Neurology, Neurophysiology and Neurobiology Unit, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy
| | - Fioravante Capone
- Neurology, Neurophysiology and Neurobiology Unit, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy
| | - Vincenzo Di Lazzaro
- Neurology, Neurophysiology and Neurobiology Unit, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy.
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Yun R, Bogaard AR, Richardson AG, Zanos S, Perlmutter SI, Fetz EE. Cortical Stimulation Paired With Volitional Unimanual Movement Affects Interhemispheric Communication. Front Neurosci 2021; 15:782188. [PMID: 35002605 PMCID: PMC8739774 DOI: 10.3389/fnins.2021.782188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 12/07/2021] [Indexed: 11/30/2022] Open
Abstract
Cortical stimulation (CS) of the motor cortex can cause excitability changes in both hemispheres, showing potential to be a technique for clinical rehabilitation of motor function. However, previous studies that have investigated the effects of delivering CS during movement typically focus on a single hemisphere. On the other hand, studies exploring interhemispheric interactions typically deliver CS at rest. We sought to bridge these two approaches by documenting the consequences of delivering CS to a single motor cortex during different phases of contralateral and ipsilateral limb movement, and simultaneously assessing changes in interactions within and between the hemispheres via local field potential (LFP) recordings. Three macaques were trained in a unimanual reaction time (RT) task and implanted with epidural or intracortical electrodes over bilateral motor cortices. During a given session CS was delivered to one hemisphere with respect to movements of either the contralateral or ipsilateral limb. Stimulation delivered before contralateral limb movement onset shortened the contralateral limb RT. In contrast, stimulation delivered after the end of contralateral movement increased contralateral RT but decreased ipsilateral RT. Stimulation delivered before ipsilateral limb movement decreased ipsilateral RT. All other stimulus conditions as well as random stimulation and periodic stimulation did not have consistently significant effects on either limb. Simultaneous LFP recordings from one animal revealed correlations between changes in interhemispheric alpha band coherence and changes in RT, suggesting that alpha activity may be indicative of interhemispheric communication. These results show that changes caused by CS to the functional coupling within and between precentral cortices is contingent on the timing of CS relative to movement.
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Affiliation(s)
- Richy Yun
- Department of Bioengineering, University of Washington, Seattle, WA, United States
- Washington National Primate Research Center, University of Washington, Seattle, WA, United States
| | - Andrew R. Bogaard
- Washington National Primate Research Center, University of Washington, Seattle, WA, United States
- Department of Physiology and Biophysics, University of Washington, Seattle, WA, United States
| | - Andrew G. Richardson
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, United States
| | - Stavros Zanos
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, New York, NY, United States
| | - Steve I. Perlmutter
- Washington National Primate Research Center, University of Washington, Seattle, WA, United States
- Department of Physiology and Biophysics, University of Washington, Seattle, WA, United States
| | - Eberhard E. Fetz
- Department of Bioengineering, University of Washington, Seattle, WA, United States
- Washington National Primate Research Center, University of Washington, Seattle, WA, United States
- Department of Physiology and Biophysics, University of Washington, Seattle, WA, United States
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A New Paired Associative Stimulation Protocol with High-Frequency Peripheral Component and High-Intensity 20 Hz Repetitive Transcranial Magnetic Stimulation-A Pilot Study. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph182111224. [PMID: 34769744 PMCID: PMC8583447 DOI: 10.3390/ijerph182111224] [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: 09/02/2021] [Revised: 10/12/2021] [Accepted: 10/21/2021] [Indexed: 11/16/2022]
Abstract
Paired associative stimulation (PAS) is a stimulation technique combining transcranial magnetic stimulation (TMS) and peripheral nerve stimulation (PNS) that can induce plastic changes in the human motor system. A PAS protocol consisting of a high-intensity single TMS pulse given at 100% of stimulator output (SO) and high-frequency 100-Hz PNS train, or "the high-PAS" was designed to promote corticomotoneuronal synapses. Such PAS, applied as a long-term intervention, has demonstrated therapeutic efficacy in spinal cord injury (SCI) patients. Adding a second TMS pulse, however, rendered this protocol inhibitory. The current study sought for more effective PAS parameters. Here, we added a third TMS pulse, i.e., a 20-Hz rTMS (three pulses at 96% SO) combined with high-frequency PNS (six pulses at 100 Hz). We examined the ability of the proposed stimulation paradigm to induce the potentiation of motor-evoked potentials (MEPs) in five human subjects and described the safety and tolerability of the new protocol in these subjects. In this study, rTMS alone was used as a control. In addition, we compared the efficacy of the new protocol in five subjects with two PAS protocols consisting of PNS trains of six pulses at 100 Hz combined with (a) single 100% SO TMS pulses (high-PAS) and (b) a 20-Hz rTMS at a lower intensity (three pulses at 120% RMT). The MEPs were measured immediately after, and 30 and 60 min after the stimulation. Although at 0 and 30 min there was no significant difference in the induced MEP potentiation between the new PAS protocol and the rTMS control, the MEP potentiation remained significantly higher at 60 min after the new PAS than after rTMS alone. At 60 min, the new protocol was also more effective than the two other PAS protocols. The new protocol caused strong involuntary twitches in three subjects and, therefore, its further characterization is needed before introducing it for clinical research. Additionally, its mechanism plausibly differs from PAS with high-frequency PNS that has been used in SCI patients.
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Vasu SO, Kaphzan H. The role of sodium channels in direct current stimulation-axonal perspective. Cell Rep 2021; 37:109832. [PMID: 34644580 DOI: 10.1016/j.celrep.2021.109832] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Revised: 06/24/2021] [Accepted: 09/23/2021] [Indexed: 11/17/2022] Open
Abstract
Transcranial neurostimulation methods are utilized as therapies for various neuropsychiatric disorders. Primarily, they entail the delivery of weak subthreshold currents across the brain, which modulate neuronal excitability. However, it is still a puzzle how such weak electrical fields actuate their effects. Previous studies showed that axons are the most sensitive subcellular compartment for direct current stimulation, and maximal polarization is achieved at their terminals. Nonetheless, polarization of axon terminals according to models was predicted to be weak, and the mechanism for substantial axon terminals polarization was obscure. Here, we show that a weak subthreshold electrical field modifies the conductance of voltage-dependent sodium channels in axon terminals, subsequently amplifying their membrane polarization. Moreover, we show that this amplification has substantial effects on synaptic functioning. Finally, we employ analytical modeling to explain how sodium currents modifications enhance axon terminal polarization. These findings relate to the mechanistic aspects of any neurostimulation technique.
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Affiliation(s)
- Sreerag Othayoth Vasu
- Laboratory for Neurobiology of Psychiatric Disorders, Sagol Department of Neurobiology, University of Haifa, 199 Aba Khoushy Avenue, Mt. Carmel, 3498838 Haifa, Israel
| | - Hanoch Kaphzan
- Laboratory for Neurobiology of Psychiatric Disorders, Sagol Department of Neurobiology, University of Haifa, 199 Aba Khoushy Avenue, Mt. Carmel, 3498838 Haifa, Israel.
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Di Lazzaro V, Bella R, Benussi A, Bologna M, Borroni B, Capone F, Chen KHS, Chen R, Chistyakov AV, Classen J, Kiernan MC, Koch G, Lanza G, Lefaucheur JP, Matsumoto H, Nguyen JP, Orth M, Pascual-Leone A, Rektorova I, Simko P, Taylor JP, Tremblay S, Ugawa Y, Dubbioso R, Ranieri F. Diagnostic contribution and therapeutic perspectives of transcranial magnetic stimulation in dementia. Clin Neurophysiol 2021; 132:2568-2607. [PMID: 34482205 DOI: 10.1016/j.clinph.2021.05.035] [Citation(s) in RCA: 78] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 04/22/2021] [Accepted: 05/28/2021] [Indexed: 02/07/2023]
Abstract
Transcranial magnetic stimulation (TMS) is a powerful tool to probe in vivo brain circuits, as it allows to assess several cortical properties such asexcitability, plasticity and connectivity in humans. In the last 20 years, TMS has been applied to patients with dementia, enabling the identification of potential markers of thepathophysiology and predictors of cognitive decline; moreover, applied repetitively, TMS holds promise as a potential therapeutic intervention. The objective of this paper is to present a comprehensive review of studies that have employed TMS in dementia and to discuss potential clinical applications, from the diagnosis to the treatment. To provide a technical and theoretical framework, we first present an overview of the basic physiological mechanisms of the application of TMS to assess cortical excitability, excitation and inhibition balance, mechanisms of plasticity and cortico-cortical connectivity in the human brain. We then review the insights gained by TMS techniques into the pathophysiology and predictors of progression and response to treatment in dementias, including Alzheimer's disease (AD)-related dementias and secondary dementias. We show that while a single TMS measure offers low specificity, the use of a panel of measures and/or neurophysiological index can support the clinical diagnosis and predict progression. In the last part of the article, we discuss the therapeutic uses of TMS. So far, only repetitive TMS (rTMS) over the left dorsolateral prefrontal cortex and multisite rTMS associated with cognitive training have been shown to be, respectively, possibly (Level C of evidence) and probably (Level B of evidence) effective to improve cognition, apathy, memory, and language in AD patients, especially at a mild/early stage of the disease. The clinical use of this type of treatment warrants the combination of brain imaging techniques and/or electrophysiological tools to elucidate neurobiological effects of neurostimulation and to optimally tailor rTMS treatment protocols in individual patients or specific patient subgroups with dementia or mild cognitive impairment.
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Affiliation(s)
- Vincenzo Di Lazzaro
- Unit of Neurology, Neurophysiology, Neurobiology, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy.
| | - Rita Bella
- Department of Medical and Surgical Sciences and Advanced Technologies, Section of Neurosciences, University of Catania, Catania, Italy
| | - Alberto Benussi
- Centre for Neurodegenerative Disorders, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Matteo Bologna
- Department of Human Neurosciences, Sapienza University of Rome, Italy; IRCCS Neuromed, Pozzilli, IS, Italy
| | - Barbara Borroni
- Centre for Neurodegenerative Disorders, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Fioravante Capone
- Unit of Neurology, Neurophysiology, Neurobiology, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy
| | - Kai-Hsiang S Chen
- Department of Neurology, National Taiwan University Hospital Hsin-Chu Branch, Hsin-Chu, Taiwan
| | - Robert Chen
- Division of Neurology, Department of Medicine, University of Toronto, Toronto, Canada; Division of Brain, Imaging& Behaviour, Krembil Brain Institute, Toronto, Canada
| | | | - Joseph Classen
- Department of Neurology, University Hospital Leipzig, Leipzig University Medical Center, Germany
| | - Matthew C Kiernan
- Department of Neurology, Royal Prince Alfred Hospital, Brain and Mind Centre, University of Sydney, Sydney, New South Wales, Australia
| | - Giacomo Koch
- Non Invasive Brain Stimulation Unit/Department of Behavioral and Clinical Neurology, Santa Lucia Foundation IRCCS, Rome, Italy; Department of Neuroscience and Rehabilitation, University of Ferrara, Ferrara, Italy
| | - Giuseppe Lanza
- Department of Surgery and Medical-Surgical Specialties, University of Catania, Catania, Italy; Department of Neurology IC, Oasi Research Institute-IRCCS, Troina, Italy
| | - Jean-Pascal Lefaucheur
- ENT Team, EA4391, Faculty of Medicine, Paris Est Créteil University, Créteil, France; Clinical Neurophysiology Unit, Department of Physiology, Henri Mondor Hospital, Assistance Publique - Hôpitaux de Paris, Créteil, France
| | | | - Jean-Paul Nguyen
- Pain Center, clinique Bretéché, groupe ELSAN, Multidisciplinary Pain, Palliative and Supportive care Center, UIC 22/CAT2 and Laboratoire de Thérapeutique (EA3826), University Hospital, Nantes, France
| | - Michael Orth
- University Hospital of Old Age Psychiatry and Psychotherapy, University of Bern, Bern, Switzerland; Swiss Huntington's Disease Centre, Siloah, Bern, Switzerland
| | - Alvaro Pascual-Leone
- Hinda and Arthur Marcus Institute for Aging Research, Center for Memory Health, Hebrew SeniorLife, USA; Department of Neurology, Harvard Medical School, Boston, MA, USA; Guttmann Brain Health Institute, Universitat Autonoma Barcelona, Spain
| | - Irena Rektorova
- Applied Neuroscience Research Group, Central European Institute of Technology, Masaryk University (CEITEC MU), Brno, Czech Republic; Department of Neurology, St. Anne's University Hospital and Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Patrik Simko
- Applied Neuroscience Research Group, Central European Institute of Technology, Masaryk University (CEITEC MU), Brno, Czech Republic; Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - John-Paul Taylor
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Sara Tremblay
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, ON, Canada; Royal Ottawa Institute of Mental Health Research, Ottawa, ON, Canada
| | - Yoshikazu Ugawa
- Department of Human Neurophysiology, School of Medicine, Fukushima Medical University, Fukushima, Japan
| | - Raffaele Dubbioso
- Department of Neurosciences, Reproductive Sciences and Odontostomatology, University of Naples "Federico II", Naples, Italy
| | - Federico Ranieri
- Unit of Neurology, Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
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Kinoshita M, Suppa A. Gear up for therapeutic application of non-invasive brain stimulation in Parkinson's disease. Clin Neurophysiol 2021; 132:2892-2893. [PMID: 34538738 DOI: 10.1016/j.clinph.2021.08.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 08/29/2021] [Indexed: 10/20/2022]
Affiliation(s)
- Masako Kinoshita
- Department of Neurology, National Hospital Organization Utano National Hospital, Kyoto, Japan.
| | - Antonio Suppa
- Department of Human Neurosciences, Sapienza University of Rome, Italy; IRCCS Neuromed Institute, Pozzilli IS, Italy
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Increasing and decreasing interregional brain coupling increases and decreases oscillatory activity in the human brain. Proc Natl Acad Sci U S A 2021; 118:2100652118. [PMID: 34507986 PMCID: PMC8449322 DOI: 10.1073/pnas.2100652118] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/21/2021] [Indexed: 11/18/2022] Open
Abstract
The origins of oscillatory activity in the brain are currently debated, but common to many hypotheses is the notion that they reflect interactions between brain areas. Here, we examine this possibility by manipulating the strength of coupling between two human brain regions, ventral premotor cortex (PMv) and primary motor cortex (M1), and examine the impact on oscillatory activity in the motor system measurable in the electroencephalogram. We either increased or decreased the strength of coupling while holding the impact on each component area in the pathway constant. This was achieved by stimulating PMv and M1 with paired pulses of transcranial magnetic stimulation using two different patterns, only one of which increases the influence exerted by PMv over M1. While the stimulation protocols differed in their temporal patterning, they were comprised of identical numbers of pulses to M1 and PMv. We measured the impact on activity in alpha, beta, and theta bands during a motor task in which participants either made a preprepared action (Go) or withheld it (No-Go). Augmenting cortical connectivity between PMv and M1, by evoking synchronous pre- and postsynaptic activity in the PMv-M1 pathway, enhanced oscillatory beta and theta rhythms in Go and No-Go trials, respectively. Little change was observed in the alpha rhythm. By contrast, diminishing the influence of PMv over M1 decreased oscillatory beta and theta rhythms in Go and No-Go trials, respectively. This suggests that corticocortical communication frequencies in the PMv-M1 pathway can be manipulated following Hebbian spike-timing-dependent plasticity.
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Altered motor cortical plasticity in patients with hepatic encephalopathy: A paired associative stimulation study. Clin Neurophysiol 2021; 132:2332-2341. [PMID: 34454259 DOI: 10.1016/j.clinph.2021.07.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 06/29/2021] [Accepted: 07/03/2021] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Hepatic encephalopathy (HE) is a potentially reversible brain dysfunction caused by liver failure. Altered synaptic plasticity is supposed to play a major role in the pathophysiology of HE. Here, we used paired associative stimulation with an inter-stimulus interval of 25 ms (PAS25), a transcranial magnetic stimulation (TMS) protocol, to test synaptic plasticity of the motor cortex in patients with manifest HE. METHODS 23 HE-patients and 23 healthy controls were enrolled in the study. Motor evoked potential (MEP) amplitudes were assessed as measure for cortical excitability. Time courses of MEP amplitude changes after the PAS25 intervention were compared between both groups. RESULTS MEP-amplitudes increased after PAS25 in the control group, indicating PAS25-induced synaptic plasticity in healthy controls, as expected. In contrast, MEP-amplitudes within the HE group did not change and were lower than in the control group, indicating no induction of plasticity. CONCLUSIONS Our study revealed reduced synaptic plasticity of the primary motor cortex in HE. SIGNIFICANCE Reduced synaptic plasticity in HE provides a link between pathological changes on the molecular level and early clinical symptoms of the disease. This decrease may be caused by disturbances in the glutamatergic neurotransmission due to the known hyperammonemia in HE patients.
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Guidali G, Roncoroni C, Bolognini N. Paired associative stimulations: Novel tools for interacting with sensory and motor cortical plasticity. Behav Brain Res 2021; 414:113484. [PMID: 34302877 DOI: 10.1016/j.bbr.2021.113484] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Revised: 06/10/2021] [Accepted: 07/19/2021] [Indexed: 12/26/2022]
Abstract
In the early 2000s, a novel non-invasive brain stimulation protocol, the paired associative stimulation (PAS), was introduced, allowing to induce and investigate Hebbian associative plasticity within the humans' motor system, with patterns resembling spike-timing-dependent plasticity properties found in cellular models. Since this evidence, PAS efficacy has been proved in healthy, and to a lesser extent, in clinical populations. Recently, novel 'modified' protocols targeting sensorimotor and crossmodal networks appeared in the literature. In the present work, we have reviewed recent advances using these 'modified' PAS protocols targeting sensory and motor cortical networks. To better categorize them, we propose a novel classification according to the nature of the peripheral and cortical stimulations (i.e., within-system, cross-systems, and cortico-cortical PAS). For each protocol of the categories mentioned above, we describe and discuss their main features, how they have been used to study and promote brain plasticity, and their advantages and disadvantages. Overall, current evidence suggests that these novel non-invasive brain stimulation protocols represent very promising tools to study the plastic properties of humans' sensorimotor and crossmodal networks, both in the healthy and in the damaged central nervous system.
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Affiliation(s)
- Giacomo Guidali
- Neurophysiology Lab, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy; Department of Psychology & NeuroMI - Milan Center for Neuroscience, University of Milano-Bicocca, Milan, Italy.
| | - Camilla Roncoroni
- Department of Psychology & NeuroMI - Milan Center for Neuroscience, University of Milano-Bicocca, Milan, Italy
| | - Nadia Bolognini
- Department of Psychology & NeuroMI - Milan Center for Neuroscience, University of Milano-Bicocca, Milan, Italy; Laboratory of Neuropsychology, IRCCS Istituto Auxologico Italiano, Milan, Italy
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Jannati A, Ryan MA, Block G, Kayarian FB, Oberman LM, Rotenberg A, Pascual-Leone A. Modulation of motor cortical excitability by continuous theta-burst stimulation in adults with autism spectrum disorder. Clin Neurophysiol 2021; 132:1647-1662. [PMID: 34030059 PMCID: PMC8197744 DOI: 10.1016/j.clinph.2021.03.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 02/23/2021] [Accepted: 03/15/2021] [Indexed: 11/21/2022]
Abstract
OBJECTIVE To test whether change in motor evoked potential (ΔMEP) induced by continuous theta-burst stimulation (cTBS) of motor cortex (M1) distinguishes adults with autism spectrum disorder (ASD) from neurotypicals, and to explore the contribution of two common polymorphisms related to neuroplasticity. METHODS 44 adult neurotypical (NT) participants (age 21-65, 34 males) and 19 adults with ASD (age 21-58, 17 males) prospectively underwent M1 cTBS. Their data were combined with previously obtained results from 35 NT and 35 ASD adults. RESULTS ΔMEP at 15 minutes post-cTBS (T15) was a significant predictor of diagnosis (p = 0.04) in the present sample (n=63). T15 remained a significant predictor in a larger sample (n=91) and when partially imputed based on T10-T20 from a yet-greater sample (N=133). T15 also remained a significant predictor of diagnosis among brain-derived neurotrophic factor (BDNF) Met+ and apolipoprotein E (APOE) ε4- subjects (p's < 0.05), but not among Met- or ε4+ subjects (p's > 0.19). CONCLUSIONS ΔMEP at T15 post-cTBS is a significant biomarker for adults with ASD, and its utility is modulated by BDNF and APOE polymorphisms. SIGNIFICANCE M1 cTBS response is a physiologic biomarker for adults with ASD in large samples, and controlling for BDNF and APOE polymorphisms can improve its diagnostic utility.
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Affiliation(s)
- Ali Jannati
- Berenson-Allen Center for Noninvasive Brain Stimulation and Division of Cognitive Neurology, Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA, USA; Neuromodulation Program and Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Boston, MA, USA; Department of Neurology, Harvard Medical School, Boston, MA, USA; F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.
| | - Mary A Ryan
- Berenson-Allen Center for Noninvasive Brain Stimulation and Division of Cognitive Neurology, Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA, USA; Neuromodulation Program and Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
| | - Gabrielle Block
- Berenson-Allen Center for Noninvasive Brain Stimulation and Division of Cognitive Neurology, Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA, USA; Neuromodulation Program and Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
| | - Fae B Kayarian
- Berenson-Allen Center for Noninvasive Brain Stimulation and Division of Cognitive Neurology, Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Lindsay M Oberman
- Berenson-Allen Center for Noninvasive Brain Stimulation and Division of Cognitive Neurology, Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA, USA; Neuromodulation Program and Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Boston, MA, USA; Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Alexander Rotenberg
- Berenson-Allen Center for Noninvasive Brain Stimulation and Division of Cognitive Neurology, Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA, USA; Neuromodulation Program and Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Boston, MA, USA; Department of Neurology, Harvard Medical School, Boston, MA, USA; F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Alvaro Pascual-Leone
- Department of Neurology, Harvard Medical School, Boston, MA, USA; Hinda and Arthur Marcus Institute for Aging Research and Deanna and Sidney Wolk Center for Memory Health, Hebrew SeniorLife, Boston, MA, USA; Guttman Brain Health Institute, Institut Guttman de Neurorehabilitació, Universitat Autónoma de Barcelona, Badalona, Barcelona, Spain.
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Opie GM, Liao WY, Semmler JG. Interactions Between Cerebellum and the Intracortical Excitatory Circuits of Motor Cortex: a Mini-Review. CEREBELLUM (LONDON, ENGLAND) 2021; 21:159-166. [PMID: 33978934 DOI: 10.1007/s12311-021-01278-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Accepted: 05/03/2021] [Indexed: 12/28/2022]
Abstract
Interactions between cerebellum (CB) and primary motor cortex (M1) are critical for effective motor function. Although the associated neurophysiological processes are yet to be fully characterised, a growing body of work using non-invasive brain stimulation (NIBS) techniques has significantly progressed our current understanding. In particular, recent developments with both transcranial magnetic (TMS) and direct current (tDCS) stimulation suggest that CB modulates the activity of local excitatory interneuronal circuits within M1. These circuits are known to be important both physiologically and functionally, and understanding the nature of their connectivity with CB therefore has the potential to provide important insight for NIBS applications. Consequently, this mini-review provides an overview of the emerging literature that has investigated interactions between CB and the intracortical excitatory circuits of M1.
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Affiliation(s)
- George M Opie
- Discipline of Physiology, Adelaide Medical School, The University of Adelaide, Adelaide, South Australia, 5005, Australia
| | - Wei-Yeh Liao
- Discipline of Physiology, Adelaide Medical School, The University of Adelaide, Adelaide, South Australia, 5005, Australia
| | - John G Semmler
- Discipline of Physiology, Adelaide Medical School, The University of Adelaide, Adelaide, South Australia, 5005, Australia.
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Castro F, Osman L, Di Pino G, Vuckovic A, Nowicky A, Bishop D. Does sonification of action simulation training impact corticospinal excitability and audiomotor plasticity? Exp Brain Res 2021; 239:1489-1505. [PMID: 33683403 PMCID: PMC8144125 DOI: 10.1007/s00221-021-06069-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 02/19/2021] [Indexed: 01/03/2023]
Abstract
Sonification is a sensory augmentation strategy whereby a sound is associated with, and modulated by, movement. Evidence suggests that sonification could be a viable strategy to maximize learning and rehabilitation. Recent studies investigated sonification of action observation, reporting beneficial effects, especially in Parkinson's disease. However, research on simulation training-a training regime based on action observation and motor imagery, in which actions are internally simulated, without physical execution-suggest that action observation alone is suboptimal, compared to the combined use of action observation and motor imagery. In this study, we explored the effects of sonified action observation and motor imagery on corticospinal excitability, as well as to evaluate the extent of practice-dependent plasticity induced by this training. Nineteen participants were recruited to complete a practice session based on combined and congruent action observation and motor imagery (AOMI) and physical imitation of the same action. Prior to the beginning, participants were randomly assigned to one of two groups, one group (nine participants) completed the practice block with sonified AOMI, while the other group (ten participants) completed the practice without extrinsic auditory information and served as control group. To investigate practice-induced plasticity, participants completed two auditory paired associative stimulation (aPAS) protocols, one completed after the practice block, and another one completed alone, without additional interventions, at least 7 days before the practice. After the practice block, both groups significantly increased their corticospinal excitability, but sonification did not exert additional benefits, compared to non-sonified conditions. In addition, aPAS significantly increased corticospinal excitability when completed alone, but when it was primed by a practice block, no modulatory effects on corticospinal excitability were found. It is possible that sonification of combined action observation and motor imagery may not be a useful strategy to improve corticospinal, but further studies are needed to explore its relationship with performance improvements. We also confirm the neuromodulatory effect of aPAS, but its interaction with audiomotor practice remain unclear.
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Affiliation(s)
- Fabio Castro
- Research Unit of Neurophysiology and Neuroengineering of Human-Technology Interaction (NeXTlab), Università Campus Bio-Medico Di Roma, Rome, Italy.
- Centre for Cognitive Neuroscience, Department of Life Sciences, College of Health, Medicine and Life Sciences, Brunel University London, Uxbridge, UK.
| | - Ladan Osman
- Department of Life Sciences, College of Health, Medicine and Life Sciences, Brunel University London, Uxbridge, UK
| | - Giovanni Di Pino
- Research Unit of Neurophysiology and Neuroengineering of Human-Technology Interaction (NeXTlab), Università Campus Bio-Medico Di Roma, Rome, Italy
| | - Aleksandra Vuckovic
- School of Engineering, College of Engineering and Science, James Watt Building (South) University of Glasgow, Glasgow, G12 8QQ, UK
| | - Alexander Nowicky
- Centre for Cognitive Neuroscience, Department of Clinical Sciences, College of Health, Medicine and Life Sciences, Brunel University London, Uxbridge, UK
| | - Daniel Bishop
- Centre for Cognitive Neuroscience, Department of Life Sciences, College of Health, Medicine and Life Sciences, Brunel University London, Uxbridge, UK
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44
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Mrachacz-Kersting N, Ibáñez J, Farina D. Towards a mechanistic approach for the development of non-invasive brain-computer interfaces for motor rehabilitation. J Physiol 2021; 599:2361-2374. [PMID: 33728656 DOI: 10.1113/jp281314] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2021] [Accepted: 03/05/2021] [Indexed: 12/11/2022] Open
Abstract
Brain-computer interfaces (BCIs) designed for motor rehabilitation use brain signals associated with motor-processing states to guide neuroplastic changes in a state-dependent manner. These technologies are uniquely positioned to induce targeted and functionally relevant plastic changes in the human motor nervous system. However, while several studies have shown that BCI-based neuromodulation interventions may improve motor function in patients with lesions in the central nervous system, the neurophysiological structures and processes targeted with the BCI interventions have not been identified. In this review, we first summarize current knowledge of the changes in the central nervous system associated with learning new motor skills. Then, we propose a classification of current BCI paradigms for plasticity induction and motor rehabilitation based on the expected neural plastic changes promoted. This classification proposes four paradigms based on two criteria: the plasticity induction methods and the brain states targeted. The existing evidence regarding the brain circuits and processes targeted with these different BCIs is discussed in detail. The proposed classification aims to serve as a starting point for future studies trying to elucidate the underlying plastic changes following BCI interventions.
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Affiliation(s)
| | - Jaime Ibáñez
- Department of Bioengineering, Centre for Neurotechnologies, Imperial College London, London, UK
- Department of Clinical and Movement Neuroscience, Institute of Neurology, University College London, London, UK
| | - Dario Farina
- Department of Bioengineering, Centre for Neurotechnologies, Imperial College London, London, UK
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45
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Guidali G, Roncoroni C, Bolognini N. Modulating Frontal Networks' Timing-Dependent-Like Plasticity With Paired Associative Stimulation Protocols: Recent Advances and Future Perspectives. Front Hum Neurosci 2021; 15:658723. [PMID: 33967723 PMCID: PMC8100231 DOI: 10.3389/fnhum.2021.658723] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 03/30/2021] [Indexed: 12/12/2022] Open
Abstract
Starting from the early 2000s, paired associative stimulation (PAS) protocols have been used in humans to study brain connectivity in motor and sensory networks by exploiting the intrinsic properties of timing-dependent cortical plasticity. In the last 10 years, PAS have also been developed to investigate the plastic properties of complex cerebral systems, such as the frontal ones, with promising results. In the present work, we review the most recent advances of this technique, focusing on protocols targeting frontal cortices to investigate connectivity and its plastic properties, subtending high-order cognitive functions like memory, decision-making, attentional, or emotional processing. Overall, current evidence reveals that PAS can be effectively used to assess, enhance or depress physiological connectivity within frontal networks in a timing-dependent way, in turn modulating cognitive processing in healthy and pathological conditions.
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Affiliation(s)
- Giacomo Guidali
- Neurophysiology Lab, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy
| | - Camilla Roncoroni
- Department of Psychology, NeuroMI - Milan Center for Neuroscience, University of Milano-Bicocca, Milan, Italy
| | - Nadia Bolognini
- Department of Psychology, NeuroMI - Milan Center for Neuroscience, University of Milano-Bicocca, Milan, Italy.,Laboratory of Neuropsychology, IRCCS Istituto Auxologico Italiano, Milan, Italy
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Shulga A, Lioumis P, Kirveskari E, Savolainen S, Mäkelä JP. A novel paired associative stimulation protocol with a high-frequency peripheral component: A review on results in spinal cord injury rehabilitation. Eur J Neurosci 2021; 53:3242-3257. [PMID: 33738876 DOI: 10.1111/ejn.15191] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 02/26/2021] [Accepted: 03/12/2021] [Indexed: 12/11/2022]
Abstract
In recent decades, a multitude of therapeutic approaches has been developed for spinal cord injury (SCI), but few have progressed to regular clinical practice. Novel non-invasive, cost-effective, and feasible approaches to treat this challenging condition are needed. A novel variant of paired associative stimulation (PAS), high-PAS, consists of non-invasive high-intensity transcranial magnetic stimulation (TMS) and non-invasive high-frequency electrical peripheral nerve stimulation (PNS). We observed a therapeutic effect of high-PAS in 20 patients with incomplete SCI with wide range of injury severity, age, and time since injury. Tetraplegic and paraplegic, traumatic, and neurological SCI patients benefited from upper- or lower-limb high-PAS. We observed increases in manual motor scores (MMT) of upper and lower limbs, functional hand tests, walking tests, and measures of functional independence. We also optimized PAS settings in several studies in healthy subjects and began elucidating the mechanisms of therapeutic action. The scope of this review is to describe the clinical experience gained with this novel PAS approach. This review is focused on the summary of our results and observations and the methodological considerations for researchers and clinicians interested in adopting and further developing this new method.
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Affiliation(s)
- Anastasia Shulga
- BioMag Laboratory, HUS Diagnostic Center, Helsinki University Hospital, University of Helsinki and Aalto University School of Science, Helsinki, Finland.,Department of Physical and Rehabilitation Medicine, Helsinki University Hospital and University of Helsinki, Helsinki, Finland
| | - Pantelis Lioumis
- BioMag Laboratory, HUS Diagnostic Center, Helsinki University Hospital, University of Helsinki and Aalto University School of Science, Helsinki, Finland.,Department of Neuroscience and Biomedical Engineering, Aalto University School of Science, Espoo, Finland
| | - Erika Kirveskari
- BioMag Laboratory, HUS Diagnostic Center, Helsinki University Hospital, University of Helsinki and Aalto University School of Science, Helsinki, Finland.,HUS Medical Imaging Center, Clinical Neurophysiology; Clinical Neurosciences, Helsinki University Hospital and University of Helsinki, Helsinki, Finland
| | - Sarianna Savolainen
- BioMag Laboratory, HUS Diagnostic Center, Helsinki University Hospital, University of Helsinki and Aalto University School of Science, Helsinki, Finland.,Validia Rehabilitation Center, Helsinki, Finland
| | - Jyrki P Mäkelä
- BioMag Laboratory, HUS Diagnostic Center, Helsinki University Hospital, University of Helsinki and Aalto University School of Science, Helsinki, Finland
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Confounding effects of caffeine on neuroplasticity induced by transcranial alternating current stimulation and paired associative stimulation. Clin Neurophysiol 2021; 132:1367-1379. [PMID: 33762129 DOI: 10.1016/j.clinph.2021.01.024] [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: 10/22/2020] [Revised: 11/27/2020] [Accepted: 01/06/2021] [Indexed: 11/23/2022]
Abstract
OBJECTIVE We examined the effects of caffeine, time of day, and alertness fluctuation on plasticity effects after transcranial alternating current stimulation (tACS) or 25 ms paired associative stimulation (PAS25) in caffeine-naïve and caffeine-adapted subjects. METHODS In two randomised, double-blinded, cross-over or placebo-controlled (caffeine) studies, we measured sixty subjects in eight sessions (n = 30, Male: Female = 1:1 in each study). RESULTS We found caffeine increased motor cortex excitability in caffeine naïve subjects. The aftereffects in caffeine naïve subjects were enhanced and prolonged when combined with PAS 25. Caffeine also increased alertness and the motor evoked potentials (MEPs) were reduced under light deprivation in caffeine consumers both with and without caffeine. In caffeine consumers, the time of day had no effect on tACS-induced plasticity. CONCLUSIONS We conclude that caffeine should be avoided or controlled as confounding factor for brain stimulation protocols. It is also important to keep the brightness constant in all sessions and study groups should not be mixed with caffeine-naïve and caffeine consuming participants. SIGNIFICANCE Caffeine is one of the confounding factors in the plasticity induction studies and it induces different excitability effects in caffeine-naïve and caffeine-adapted subjects. This study was registered in the ClinicalTrials.gov with these registration IDs: 1) NCT03720665 https://clinicaltrials.gov/ct2/results?cond=NCT03720665&term=&cntry=&state=&city=&dist= 2) NCT04011670 https://clinicaltrials.gov/ct2/results?cond=&term=NCT04011670&cntry=&state=&city=&dist=.
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Guerra A, Rocchi L, Grego A, Berardi F, Luisi C, Ferreri F. Contribution of TMS and TMS-EEG to the Understanding of Mechanisms Underlying Physiological Brain Aging. Brain Sci 2021; 11:405. [PMID: 33810206 PMCID: PMC8004753 DOI: 10.3390/brainsci11030405] [Citation(s) in RCA: 10] [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: 02/10/2021] [Revised: 03/19/2021] [Accepted: 03/19/2021] [Indexed: 12/21/2022] Open
Abstract
In the human brain, aging is characterized by progressive neuronal loss, leading to disruption of synapses and to a degree of failure in neurotransmission. However, there is increasing evidence to support the notion that the aged brain has a remarkable ability to reorganize itself, with the aim of preserving its physiological activity. It is important to develop objective markers able to characterize the biological processes underlying brain aging in the intact human, and to distinguish them from brain degeneration associated with many neurological diseases. Transcranial magnetic stimulation (TMS), coupled with electromyography or electroencephalography (EEG), is particularly suited to this aim, due to the functional nature of the information provided, and thanks to the ease with which it can be integrated with behavioral manipulation. In this review, we aimed to provide up to date information about the role of TMS and TMS-EEG in the investigation of brain aging. In particular, we focused on data about cortical excitability, connectivity and plasticity, obtained by using readouts such as motor evoked potentials and transcranial evoked potentials. Overall, findings in the literature support an important potential contribution of TMS to the understanding of the mechanisms underlying normal brain aging. Further studies are needed to expand the current body of information and to assess the applicability of TMS findings in the clinical setting.
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Affiliation(s)
| | - Lorenzo Rocchi
- Department of Clinical and Movements Neurosciences, UCL Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK;
- Department of Medical Sciences and Public Health, University of Cagliari, 09124 Cagliari, Italy
| | - Alberto Grego
- Department of Neuroscience, University of Padua, 35122 Padua, Italy; (A.G.); (F.B.); (C.L.)
| | - Francesca Berardi
- Department of Neuroscience, University of Padua, 35122 Padua, Italy; (A.G.); (F.B.); (C.L.)
| | - Concetta Luisi
- Department of Neuroscience, University of Padua, 35122 Padua, Italy; (A.G.); (F.B.); (C.L.)
| | - Florinda Ferreri
- Department of Neuroscience, University of Padua, 35122 Padua, Italy; (A.G.); (F.B.); (C.L.)
- Department of Clinical Neurophysiology, Kuopio University Hospital, University of Eastern Finland, 70210 Kuopio, Finland
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Guerra A, Asci F, Zampogna A, D'Onofrio V, Berardelli A, Suppa A. The effect of gamma oscillations in boosting primary motor cortex plasticity is greater in young than older adults. Clin Neurophysiol 2021; 132:1358-1366. [PMID: 33781703 DOI: 10.1016/j.clinph.2021.01.032] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 12/29/2020] [Accepted: 01/14/2021] [Indexed: 01/01/2023]
Abstract
OBJECTIVE In healthy subjects, the long-term potentiation (LTP)-like plasticity of the primary motor cortex (M1) induced by intermittent theta-burst stimulation (iTBS) can be boosted by modulating gamma (γ) oscillations through transcranial alternating current stimulation (tACS). γ-tACS also reduces short-interval intracortical inhibition (SICI). We tested whether the effects of γ-tACS differ between young (YA) and older adults (OA). METHODS Twenty YA (27.2 ± 2.7 years) and twenty OA (65.3 ± 9.5 years) underwent iTBS-γ tACS and iTBS-sham tACS in randomized sessions. In a separate session, we delivered γ-tACS alone and recorded SICI during stimulation. RESULTS iTBS-sham tACS produced comparable motor evoked potential (MEP) facilitation between groups. While iTBS-γ tACS boosted MEP facilitation in both the YA and OA groups, the magnitude of its effect was significantly lower in OA. Similarly, γ-tACS-induced modulation of GABA-A-ergic neurotransmission, as tested by SICI, was reduced in OA. The effect of iTBS-γ tACS negatively correlated with the age of OA subjects. CONCLUSIONS Mechanisms underlying the effects of γ oscillations on LTP-like plasticity become less efficient in older adults. This could reflect age-related changes in neural elements of M1 resonant to γ oscillations, including GABA-A-ergic interneurons. SIGNIFICANCE The beneficial effect of γ-tACS on iTBS-induced plasticity is reduced in older adults.
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Affiliation(s)
- Andrea Guerra
- IRCCS Neuromed, Via Atinense 18, 86077 Pozzilli, IS, Italy
| | - Francesco Asci
- IRCCS Neuromed, Via Atinense 18, 86077 Pozzilli, IS, Italy
| | - Alessandro Zampogna
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università 30, 00185 Rome, Italy
| | - Valentina D'Onofrio
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università 30, 00185 Rome, Italy
| | - Alfredo Berardelli
- IRCCS Neuromed, Via Atinense 18, 86077 Pozzilli, IS, Italy; Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università 30, 00185 Rome, Italy.
| | - Antonio Suppa
- IRCCS Neuromed, Via Atinense 18, 86077 Pozzilli, IS, Italy; Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università 30, 00185 Rome, Italy
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50
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Pohjonen M, Savolainen S, Arokoski J, Shulga A. Omitting TMS component from paired associative stimulation with high-frequency PNS: A case series of tetraplegic patients. Clin Neurophysiol Pract 2021; 6:81-87. [PMID: 33748549 PMCID: PMC7970010 DOI: 10.1016/j.cnp.2021.01.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 11/16/2020] [Accepted: 01/24/2021] [Indexed: 01/19/2023] Open
Abstract
Objectives Earlier studies have shown how chronic spinal cord injury (SCI) patients have benefitted from paired associative stimulation (PAS), consisting of high-frequency peripheral nerve stimulation (PNS) and high-intensity transcranial magnetic stimulation (TMS). Since high-frequency PNS is poorly characterized, its therapeutic effect without TMS should be evaluated. We tested the effect of PNS combined with motor imagery in chronic SCI patients using the same parameters of PNS as in earlier PAS-based studies that also used TMS. Methods Five patients with chronic incomplete SCI and tetraplegia received a 6-week treatment of PNS combined with motor imagery to the weaker upper limb. Patients were evaluated with Manual Muscle Testing (MMT), hand function tests (Box and block, grip and pinch strength dynamometry), and spasticity. Results There was no significant change in hand function tests or spasticity. MMT values improved significantly immediately after the PNS period (0.59 ± 0.17, p = 0.043) and in the 1-month follow-up visit (0.87 ± 0.18, p = 0.043). However, improvement of MMT values was weaker than in chronic tetraplegic patients in a corresponding PAS study that used identical PNS stimulation but also included the TMS component omitted here (Tolmacheva et al., 2019a, Clin Neurophysiol Pract). Conclusions The lack of effect on functional hand tests with the protocol presented here suggests that the synergistic effect of PNS and TMS components is essential for the full therapeutic effect previously observed with PAS intervention. The moderate improvement of the MMT score suggests the possible usefulness of PNS and motor imagery for some of those tetraplegic SCI patients who have contraindications to TMS. Significance These results add to the understanding of the PAS therapeutic mechanism by highlighting the importance of dual stimulation for achieving the full therapeutic effect of long-term PAS with a high-frequency PNS component.
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Affiliation(s)
- Markus Pohjonen
- Department of Physical and Rehabilitation Medicine, Helsinki University Hospital, Helsinki, Finland.,HUS Medical Imaging Center, BioMag Laboratory, University of Helsinki and Helsinki University Hospital, Finland
| | - Sarianna Savolainen
- HUS Medical Imaging Center, BioMag Laboratory, University of Helsinki and Helsinki University Hospital, Finland
| | - Jari Arokoski
- Department of Physical and Rehabilitation Medicine, Helsinki University Hospital, Helsinki, Finland.,Clinicum, University of Helsinki, Helsinki, Finland
| | - Anastasia Shulga
- HUS Medical Imaging Center, BioMag Laboratory, University of Helsinki and Helsinki University Hospital, Finland.,Clinical Neurosciences, Neurology, Helsinki University Hospital, Helsinki, Finland
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