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Garcia MAC, Carvalho TSD, Matsuda RH, Baffa O, Imbiriba LA, Souza VH. Forearm Posture Affects the Corticospinal Excitability of Intrinsic and Extrinsic Hand Muscles in Dominant and Nondominant Sides. J Appl Biomech 2024; 40:316-322. [PMID: 38925535 DOI: 10.1123/jab.2022-0314] [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: 12/21/2022] [Revised: 10/06/2023] [Accepted: 04/17/2024] [Indexed: 06/28/2024]
Abstract
Different forearm postures can modulate corticospinal excitability. However, there is no consensus on whether handedness plays a role in such a mechanism. This study investigated the effects of 3 forearm postures (pronation, neutral, and supination) on the corticospinal excitability of muscles from the dominant and nondominant upper limbs. Surface electromyography was recorded from the abductor digiti minimi, flexor pollicis brevis, and flexor carpi radialis from both sides of 12 right-handed volunteers. Transcranial magnetic stimulation pulses were applied to each muscle's hotspot in both cerebral hemispheres. Motor-evoked potential peak-to-peak amplitude and latency and resting motor threshold were measured. The data were evaluated by analysis of variance. The level of significance was set at 5%. The resting motor threshold was similar for the 3 muscles and both sides. Motor-evoked potential peak-to-peak amplitude from flexor pollicis brevis was lower during supination, and the dominant upper limb latency was longer. The flexor carpi radialis presented lower motor-evoked potential peak-to-peak amplitudes for neutral and shorter latencies during supination. Abductor digiti minimi seemed not to be affected by posture or side. Different muscles from dominant and nondominant sides may undergo corticospinal modulation, even distally localized from a particular joint and under rest.
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Affiliation(s)
- Marco Antonio Cavalcanti Garcia
- Programa de Pós-Graduação em Ciências da Reabilitação e Desempenho Físico-Funcional, Faculdade de Fisioterapia, Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brazil
- Grupo de Estudos em Neuro Biomecânica, Faculdade de Fisioterapia, Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brazil
- Departamento de Biofísica e Fisiologia, Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brazil
| | - Thiago Santos de Carvalho
- Departamento de Biociências e Atividades Físicas, Escola de Educação Física e Desportos, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Renan Hiroshi Matsuda
- Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Oswaldo Baffa
- Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Luis Aureliano Imbiriba
- Departamento de Biociências e Atividades Físicas, Escola de Educação Física e Desportos, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Victor Hugo Souza
- Programa de Pós-Graduação em Ciências da Reabilitação e Desempenho Físico-Funcional, Faculdade de Fisioterapia, Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brazil
- Grupo de Estudos em Neuro Biomecânica, Faculdade de Fisioterapia, Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brazil
- Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
- Department of Neuroscience and Biomedical Engineering, Aalto University, School of Science, Espoo, Finland
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Breveglieri R, Brandolani R, Diomedi S, Lappe M, Galletti C, Fattori P. Modulation of reaching by spatial attention. Front Integr Neurosci 2024; 18:1393690. [PMID: 38817775 PMCID: PMC11138159 DOI: 10.3389/fnint.2024.1393690] [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: 02/29/2024] [Accepted: 04/30/2024] [Indexed: 06/01/2024] Open
Abstract
Attention is needed to perform goal-directed vision-guided movements. We investigated whether the direction of covert attention modulates movement outcomes and dynamics. Right-handed and left-handed volunteers attended to a spatial location while planning a reach toward the same hemifield, the opposite one, or planned a reach without constraining attention. We measured behavioral variables as outcomes of ipsilateral and contralateral reaching and the tangling of behavioral trajectories obtained through principal component analysis as a measure of the dynamics of motor control. We found that the direction of covert attention had significant effects on the dynamics of motor control, specifically during contralateral reaching. Data suggest that motor control was more feedback-driven when attention was directed leftward than when attention was directed rightward or when it was not constrained, irrespectively of handedness. These results may help to better understand the neural bases of asymmetrical neurological diseases like hemispatial neglect.
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Affiliation(s)
- Rossella Breveglieri
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Riccardo Brandolani
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
- Center for Neuroscience, University of Camerino, Camerino, Italy
| | - Stefano Diomedi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Markus Lappe
- Department of Psychology, Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Münster, Münster, Germany
| | - Claudio Galletti
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Patrizia Fattori
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
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Koponen LM, Martinez M, Wood E, Murphy DLK, Goetz SM, Appelbaum LG, Peterchev AV. Transcranial magnetic stimulation input-output curve slope differences suggest variation in recruitment across muscle representations in primary motor cortex. Front Hum Neurosci 2024; 18:1310320. [PMID: 38384332 PMCID: PMC10879434 DOI: 10.3389/fnhum.2024.1310320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 01/29/2024] [Indexed: 02/23/2024] Open
Abstract
Measurement of the input-output (IO) curves of motor evoked potentials (MEPs) elicited by transcranial magnetic stimulation (TMS) can be used to assess corticospinal excitability and motor recruitment. While IO curves have been used to study disease and pharmacology, few studies have compared the IO curves across the body. This study sought to characterize IO curve parameters across the dominant and non-dominant sides of upper and lower limbs in healthy participants. Laterality preferences were assessed in eight healthy participants and IO curves were measured bilaterally for the first dorsal interosseous (FDI), biceps brachii (BB), and tibialis anterior (TA) muscles. Results show that FDI has lower motor threshold than BB which is, in turn, lower than TA. In addition, both BB and TA have markedly shallower logarithmic IO curve slopes from small to large MEP responses than FDI. After normalizing these slopes by their midpoints to account for differences in motor thresholds, which could result from geometric factors such as the target depth, large differences in logarithmic slopes remain present between all three muscles. The differences in slopes between the muscles could not be explained by differences in normalized IO curve spreads, which relate to the extent of the cortical representation and were comparable across the muscles. The IO curve differences therefore suggest muscle-dependent variations in TMS-evoked recruitment across the primary motor cortex, which should be considered when utilizing TMS-evoked MEPs to study disease states and treatment effects.
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Affiliation(s)
- Lari M. Koponen
- Department of Psychiatry and Behavioral Sciences, Duke University, Durham, NC, United States
- Centre for Human Brain Health, School of Psychology, University of Birmingham, Birmingham, UK
| | - Miles Martinez
- Department of Psychiatry and Behavioral Sciences, Duke University, Durham, NC, United States
- Center for Cognitive Neuroscience, Duke University, Durham, NC, United States
- Department of Electrical and Computer Engineering, Duke University, Durham, NC, United States
| | - Eleanor Wood
- Department of Psychiatry and Behavioral Sciences, Duke University, Durham, NC, United States
| | - David L. K. Murphy
- Department of Psychiatry and Behavioral Sciences, Duke University, Durham, NC, United States
| | - Stefan M. Goetz
- Department of Psychiatry and Behavioral Sciences, Duke University, Durham, NC, United States
- Department of Electrical and Computer Engineering, Duke University, Durham, NC, United States
- Department of Neurosurgery, Duke University, Durham, NC, United States
| | - Lawrence G. Appelbaum
- Department of Psychiatry and Behavioral Sciences, Duke University, Durham, NC, United States
- Department of Psychiatry, University of California, San Diego, San Diego, CA, United States
| | - Angel V. Peterchev
- Department of Psychiatry and Behavioral Sciences, Duke University, Durham, NC, United States
- Department of Electrical and Computer Engineering, Duke University, Durham, NC, United States
- Department of Neurosurgery, Duke University, Durham, NC, United States
- Department of Biomedical Engineering, Duke University, Durham, NC, United States
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Shanks MJ, Cirillo J, Stinear CM, Byblow WD. Reliability of a TMS-derived threshold matrix of corticomotor function. Exp Brain Res 2023; 241:2829-2843. [PMID: 37898579 PMCID: PMC10635992 DOI: 10.1007/s00221-023-06725-3] [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: 08/04/2023] [Accepted: 10/18/2023] [Indexed: 10/30/2023]
Abstract
Transcranial magnetic stimulation (TMS) studies typically focus on suprathreshold motor evoked potentials (MEPs), overlooking small MEPs representing subthreshold corticomotor pathway activation. Assessing subthreshold excitability could provide insights into corticomotor pathway integrity and function, particularly in neurological conditions like stroke. The aim of the study was to examine the test-retest reliability of metrics derived from a novel compositional analysis of MEP data from older adults. The study also compared the composition between the dominant (D) and non-dominant (ND) sides and explored the association between subthreshold responses and resting motor threshold. In this proof-of-concept study, 23 healthy older adults participated in two identical experimental sessions. Stimulus-response (S-R) curves and threshold matrices were constructed using single-pulse TMS across intensities to obtain MEPs in four upper limb muscles. S-R curves had reliable slopes for every muscle (Intraclass Correlation Coefficient range = 0.58-0.88). Subliminal and suprathreshold elements of the threshold matrix showed good-excellent reliability (D subliminal ICC = 0.83; ND subliminal ICC = 0.79; D suprathreshold ICC = 0.92; ND suprathreshold ICC = 0.94). By contrast, subthreshold elements of the matrix showed poor reliability, presumably due to a floor effect (D subthreshold ICC = 0.39; ND subthreshold ICC = 0.05). No composition differences were found between D and ND sides (suprathreshold BF01 = 3.85; subthreshold BF01 = 1.68; subliminal BF01 = 3.49). The threshold matrix reliably assesses subliminal and suprathreshold MEPs in older adults. Further studies are warranted to evaluate the utility of compositional analyses for assessing recovery of corticomotor pathway function after neurological injury.
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Affiliation(s)
- Maxine J Shanks
- Department of Exercise Sciences, University of Auckland, Auckland, New Zealand
- Centre for Brain Research, University of Auckland, Auckland, New Zealand
| | - John Cirillo
- Department of Exercise Sciences, University of Auckland, Auckland, New Zealand
- Centre for Brain Research, University of Auckland, Auckland, New Zealand
| | - Cathy M Stinear
- Centre for Brain Research, University of Auckland, Auckland, New Zealand
- Department of Medicine, University of Auckland, Auckland, New Zealand
| | - Winston D Byblow
- Department of Exercise Sciences, University of Auckland, Auckland, New Zealand.
- Centre for Brain Research, University of Auckland, Auckland, New Zealand.
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Režić Mužinić N, Markotić A, Pavelin S, Polančec D, Buljubašić Šoda M, Bralić A, Šoda J, Mastelić A, Mikac U, Jerković A, Rogić Vidaković M. Expression of CD40 and CD192 in Classical Monocytes in Multiple Sclerosis Patients Assessed with Transcranial Magnetic Stimulation. Biomedicines 2023; 11:2870. [PMID: 37893243 PMCID: PMC10603866 DOI: 10.3390/biomedicines11102870] [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: 09/19/2023] [Revised: 10/16/2023] [Accepted: 10/18/2023] [Indexed: 10/29/2023] Open
Abstract
Expression of CD40 and CD192 markers in different monocyte subpopulations has been reported to be altered in people with MS (pwMS). Also, functional connectivity of the corticospinal motor system pathway alterations has been proved by transcranial magnetic stimulation (TMS). The study objective was to investigate the expression of CD40 and CD192 in classical (CD14++CD16-), intermediate CD14++CD16+ and non-classical (CD14+CD16++) blood monocyte subpopulations in pwMS, undergoing neurophysiological TMS assessment of the corticospinal tract integrity by recording motor-evoked potentials (MEPs). Radiological examination on lesion detection with MRI was performed for 23 patients with relapsing-remitting MS treated with teriflunomide. Then, immunological analysis was conducted on peripheral blood samples collected from the patients and 10 healthy controls (HC). The blood samples were incubated with anti-human CD14, CD16, CD40 and CD192 antibodies. Next, pwMS underwent neurological testing of functional disability (EDSS) and TMS assessment with recording MEPs from upper and lower extremity muscles. The results show that in comparison to HC subjects, both pwMS with normal and altered MEP findings (prolonged MEP latency or absent MEP response) had significantly decreased surface receptor expression measured (MFIs) of CD192 and increased CD40 MFI in classical monocytes, and significantly increased percentages of classical and total monocytes positive for CD40. Knowing CD40's pro-inflammatory action, and CD192 as a molecule that enables the passing of monocytes into the brain, decreased CD192 in classical monocytes could represent a beneficial anti-inflammatory parameter.
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Affiliation(s)
- Nikolina Režić Mužinić
- Department of Medical Chemistry and Biochemistry, School of Medicine, University of Split, 21000 Split, Croatia; (A.M.)
| | - Anita Markotić
- Department of Medical Chemistry and Biochemistry, School of Medicine, University of Split, 21000 Split, Croatia; (A.M.)
| | - Sanda Pavelin
- Department of Neurology, University Hospital of Split, 21000 Split, Croatia
| | | | | | - Antonia Bralić
- Department of Interventional and Diagnostic Radiology, University Hospital of Split, 21000 Split, Croatia
| | - Joško Šoda
- Signal Processing, Analysis, Advanced Diagnostics Research and Education Laboratory (SPAADREL), Department for Marine Electrical Engineering and Information Technologies, Faculty of Maritime Studies, University of Split, 21000 Split, Croatia
| | - Angela Mastelić
- Department of Medical Chemistry and Biochemistry, School of Medicine, University of Split, 21000 Split, Croatia; (A.M.)
| | - Una Mikac
- Department of Psychology, Faculty of Humanities and Social Sciences, University of Zagreb, 10000 Zagreb, Croatia
| | - Ana Jerković
- Laboratory for Human and Experimental Neurophysiology, Department of Neuroscience, School of Medicine, University of Split, 21000 Split, Croatia
| | - Maja Rogić Vidaković
- Laboratory for Human and Experimental Neurophysiology, Department of Neuroscience, School of Medicine, University of Split, 21000 Split, Croatia
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Rogić Vidaković M, Ćurković Katić A, Pavelin S, Bralić A, Mikac U, Šoda J, Jerković A, Mastelić A, Dolić K, Markotić A, Đogaš Z, Režić Mužinić N. Transcranial Magnetic Stimulation Measures, Pyramidal Score on Expanded Disability Status Scale and Magnetic Resonance Imaging of Corticospinal Tract in Multiple Sclerosis. Bioengineering (Basel) 2023; 10:1118. [PMID: 37892848 PMCID: PMC10604490 DOI: 10.3390/bioengineering10101118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 09/20/2023] [Accepted: 09/22/2023] [Indexed: 10/29/2023] Open
Abstract
Probing the cortic ospinal tract integrity by transcranial magnetic stimulation (TMS) could help to understand the neurophysiological correlations of multiple sclerosis (MS) symptoms. Therefore, the study objective was, first, to investigate TMS measures (resting motor threshold-RMT, motor evoked potential (MEP) latency, and amplitude) of corticospinal tract integrity in people with relapsing-remitting MS (pwMS). Then, the study examined the conformity of TMS measures with clinical disease-related (Expanded Disability Status Scale-EDSS) and magnetic resonance imaging (MRI) results (lesion count) in pwMS. The e-field navigated TMS, MRI, and EDSS data were collected in 23 pwMS and compared to non-clinical samples. The results show that pwMS differed from non-clinical samples in MEP latency for upper and lower extremity muscles. Also, pwMS with altered MEP latency (prolonged or absent MEP response) had higher EDSS, general and pyramidal, functional scores than pwMS with normal MEP latency finding. Furthermore, the RMT intensity for lower extremity muscles was predictive of EDSS functional pyramidal scores. TMS/MEP latency findings classified pwMS as the same as EDSS functional pyramidal scores in 70-83% of cases and were similar to the MRI results, corresponding to EDSS functional pyramidal scores in 57-65% of cases. PwMS with altered MEP latency differed from pwMS with normal MEP latency in the total number of lesions in the brain corticospinal and cervical corticospinal tract. The study provides preliminary results on the correspondence of MRI and TMS corticospinal tract evaluation results with EDSS functional pyramidal score results in MS.
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Affiliation(s)
- Maja Rogić Vidaković
- Laboratory for Human and Experimental Neurophysiology, Department of Neuroscience, School of Medicine, University of Split, 21000 Split, Croatia; (A.J.); (Z.Đ.)
| | - Ana Ćurković Katić
- Department of Neurology, University Hospital of Split, 21000 Split, Croatia;
| | - Sanda Pavelin
- Department of Neurology, University Hospital of Split, 21000 Split, Croatia;
| | - Antonia Bralić
- Department of Interventional and Diagnostic Radiology, University Hospital of Split, 21000 Split, Croatia; (A.B.); (K.D.)
| | - Una Mikac
- Department of Psychology, Faculty of Humanities and Social Sciences University of Zagreb, 10000 Zagreb, Croatia;
| | - Joško Šoda
- Signal Processing, Analysis, Advanced Diagnostics Research and Education Laboratory (SPAADREL), Faculty of Maritime Studies, Department for Marine Electrical Engineering and Information Technologies, University of Split, 21000 Split, Croatia;
| | - Ana Jerković
- Laboratory for Human and Experimental Neurophysiology, Department of Neuroscience, School of Medicine, University of Split, 21000 Split, Croatia; (A.J.); (Z.Đ.)
| | - Angela Mastelić
- Department of Medical Chemistry and Biochemistry, School of Medicine, University of Split, 21000 Split, Croatia; (A.M.); (A.M.); (N.R.M.)
| | - Krešimir Dolić
- Department of Interventional and Diagnostic Radiology, University Hospital of Split, 21000 Split, Croatia; (A.B.); (K.D.)
- Department of Radiology, School of Medicine, University of Split, 21000 Split, Croatia
| | - Anita Markotić
- Department of Medical Chemistry and Biochemistry, School of Medicine, University of Split, 21000 Split, Croatia; (A.M.); (A.M.); (N.R.M.)
| | - Zoran Đogaš
- Laboratory for Human and Experimental Neurophysiology, Department of Neuroscience, School of Medicine, University of Split, 21000 Split, Croatia; (A.J.); (Z.Đ.)
| | - Nikolina Režić Mužinić
- Department of Medical Chemistry and Biochemistry, School of Medicine, University of Split, 21000 Split, Croatia; (A.M.); (A.M.); (N.R.M.)
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Spampinato DA, Casula EP, Koch G. The Cerebellum and the Motor Cortex: Multiple Networks Controlling Multiple Aspects of Behavior. Neuroscientist 2023:10738584231189435. [PMID: 37649430 DOI: 10.1177/10738584231189435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
The cerebellum and its thalamic projections to the primary motor cortex (M1) are well known to play an essential role in executing daily actions. Anatomic investigations in animals and postmortem humans have established the reciprocal connections between these regions; however, how these pathways can shape cortical activity in behavioral contexts and help promote recovery in neuropathological conditions remains not well understood. The present review aims to provide a comprehensive description of these pathways in animals and humans and discuss how novel noninvasive brain stimulation (NIBS) methods can be used to gain a deeper understanding of the cerebellar-M1 connections. In the first section, we focus on recent animal literature that details how information sent from the cerebellum and thalamus is integrated into an broad network of cortical motor neurons. We then discuss how NIBS approaches in humans can be used to reliably assess the connectivity between the cerebellum and M1. Moreover, we provide the latest perspectives on using advanced NIBS approaches to investigate and modulate multiple cerebellar-cortical networks involved in movement behavior and plasticity. Finally, we discuss how these emerging methods have been used in translation research to produce long-lasting modifications of cerebellar-thalamic-M1 to restore cortical activity and motor function in neurologic patients.
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Cantone M, Fisicaro F, Ferri R, Bella R, Pennisi G, Lanza G, Pennisi M. Sex differences in mild vascular cognitive impairment: A multimodal transcranial magnetic stimulation study. PLoS One 2023; 18:e0282751. [PMID: 36867595 PMCID: PMC9983846 DOI: 10.1371/journal.pone.0282751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 02/21/2023] [Indexed: 03/04/2023] Open
Abstract
BACKGROUND Sex differences in vascular cognitive impairment (VCI) at risk for future dementia are still debatable. Transcranial magnetic stimulation (TMS) is used to evaluate cortical excitability and the underlying transmission pathways, although a direct comparison between males and females with mild VCI is lacking. METHODS Sixty patients (33 females) underwent clinical, psychopathological, functional, and TMS assessment. Measures of interest consisted of: resting motor threshold, latency of motor evoked potentials (MEPs), contralateral silent period, amplitude ratio, central motor conduction time (CMCT), including the F wave technique (CMCT-F), short-interval intracortical inhibition (SICI), intracortical facilitation, and short-latency afferent inhibition, at different interstimulus intervals (ISIs). RESULTS Males and females were comparable for age, education, vascular burden, and neuropsychiatric symptoms. Males scored worse at global cognitive tests, executive functioning, and independence scales. MEP latency was significantly longer in males, from both sides, as well CMCT and CMCT-F from the left hemisphere; a lower SICI at ISI of 3 ms from the right hemisphere was also found. After correction for demographic and anthropometric features, the effect of sex remained statistically significant for MEP latency, bilaterally, and for CMCT-F and SICI. The presence of diabetes, MEP latency bilaterally, and both CMCT and CMCT-F from the right hemisphere inversely correlated with executive functioning, whereas TMS did not correlate with vascular burden. CONCLUSIONS We confirm the worse cognitive profile and functional status of males with mild VCI compared to females and first highlight sex-specific changes in intracortical and cortico-spinal excitability to multimodal TMS in this population. This points to some TMS measures as potential markers of cognitive impairment, as well as targets for new drugs and neuromodulation therapies.
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Affiliation(s)
- Mariagiovanna Cantone
- Neurology Unit, University Hospital Policlinico “G. Rodolico-San Marco”, Catania, Italy
| | - Francesco Fisicaro
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Raffaele Ferri
- Clinical Neurophysiology Research Unit, Oasi Research Institute-IRCCS, Troina, Italy
| | - Rita Bella
- Department of Medical and Surgical Sciences and Advanced Technologies, University of Catania, Catania, Italy
| | - Giovanni Pennisi
- Clinical Neurophysiology Research Unit, Oasi Research Institute-IRCCS, Troina, Italy
| | - Giuseppe Lanza
- Clinical Neurophysiology Research Unit, Oasi Research Institute-IRCCS, Troina, Italy
- Department of Surgery and Medical-Surgical Specialties, University of Catania, Catania, Italy
- * E-mail:
| | - Manuela Pennisi
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
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Jitsakulchaidej P, Wivatvongvana P, Kitisak K. Normal parameters for diagnostic transcranial magnetic stimulation using a parabolic coil with biphasic pulse stimulation. BMC Neurol 2022; 22:510. [PMID: 36585660 PMCID: PMC9805266 DOI: 10.1186/s12883-022-02977-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 11/10/2022] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND TMS is being used to aid in the diagnosis of central nervous system (CNS) illnesses. It is useful in planning rehabilitation programs and setting appropriate goals for patients. We used a parabolic coil with biphasic pulse stimulation to find normal values for diagnostic TMS parameters. OBJECTIVES 1. To determine the normal motor threshold (MT), motor evoked potentials (MEP), central motor conduction time (CMCT), intracortical facilitation (ICF), short-interval intracortical inhibition (SICI), and silent period (SP) values. 2. To measure the MEP latencies of abductor pollicis brevis (APB) and extensor digitorum brevis (EDB) at various ages, heights, and arm and leg lengths. STUDY DESIGN Descriptive Study. SETTING Department of Rehabilitation Medicine, Chiang Mai University, Thailand. SUBJECTS Forty-eight healthy participants volunteered for the study. METHODS All participants received a single diagnostic TMS using a parabolic coil with biphasic pulse stimulation on the left primary motor cortex (M1). All parameters: MT, MEP, CMCT, ICF, SICI, and SP were recorded through surface EMGs at the right APB and EDB. Outcome parameters were reported by the mean and standard deviation (SD) or median and interquartile range (IQR), according to data distribution. MEP latencies of APB and EDB were also measured at various ages, heights, and arm and leg lengths. RESULTS APB-MEP latencies at 120% and 140% MT were 21.77 ± 1.47 and 21.17 ± 1.44 ms. APB-CMCT at 120% and 140% MT were 7.81 ± 1.32 and 7.19 ± 1.21 ms. APB-MEP amplitudes at 120% and 140% MT were 1.04 (0.80-1.68) and 2.24 (1.47-3.52) mV. EDB-MEP latencies at 120% and 140% MT were 37.14 ± 2.85 and 36.46 ± 2.53 ms. EDB-CMCT at 120% and 140% MT were 14.33 ± 2.50 and 13.63 ± 2.57 ms. EDB-MEP amplitudes at 120% and 140% MT were 0.60 (0.38-0.98) and 0.95 (0.69-1.55) mV. ICF amplitudes of APB and EDB were 2.26 (1.61-3.49) and 1.26 (0.88-1.98) mV. SICI amplitudes of APB and EDB were 0.21 (0.13-0.51) and 0.18 (0.09-0.29) mV. MEP latencies of APB at 120% and 140% MT were different between heights < 160 cm and ≥ 160 cm (p < 0.001 and p < 0.001) and different between arm lengths < 65 and ≥ 65 cm (p = 0.022 and p = 0.002). CONCLUSION We established diagnostic TMS measurements using a parabolic coil with a biphasic pulse configuration. EDB has a higher MT than APB. The 140/120 MEP ratio of APB and EDB is two-fold. The optimal MEP recording for APB is 120%, whereas EDB is 140% of MT. CMCT by the F-wave is more convenient and tolerable for patients. ICF provides a twofold increase in MEP amplitude. SICI provides a ¼-fold of MEP amplitude. SP from APB and EDB are 121.58 ± 21.50 and 181.01 ± 40.99 ms, respectively. Height and MEP latencies have a modest relationship, whereas height and arm length share a strong positive correlation.
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Affiliation(s)
- Pimthong Jitsakulchaidej
- grid.7132.70000 0000 9039 7662Department of Rehabilitation Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200 Thailand
| | - Pakorn Wivatvongvana
- grid.7132.70000 0000 9039 7662Department of Rehabilitation Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200 Thailand
| | - Kittipong Kitisak
- grid.7132.70000 0000 9039 7662Department of Rehabilitation Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200 Thailand
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van den Bos MAJ, Menon P, Vucic S. Cortical hyperexcitability and plasticity in Alzheimer's disease: developments in understanding and management. Expert Rev Neurother 2022; 22:981-993. [PMID: 36683586 DOI: 10.1080/14737175.2022.2170784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
INTRODUCTION Transcranial magnetic stimulation (TMS) is a non-invasive neurophysiological tool that provides important insights into Alzheimer's Disease (AD). A significant body of work utilizing TMS techniques has explored the pathophysiological relevance of cortical hyperexcitability and plasticity in AD and their modulation in novel therapies. AREAS COVERED This review examines the technique of TMS, the use of TMS to examine specific features of cortical excitability and the use of TMS techniques to modulate cortical function. A search was performed utilizing the PubMed database to identify key studies utilizing TMS to examine cortical hyperexcitability and plasticity in Alzheimer's dementia. We then translate this understanding to the study of Alzheimer's disease pathophysiology, examining the underlying neurophysiologic links contributing to these twin signatures, cortical hyperexcitability and abnormal plasticity, in the cortical dysfunction characterizing AD. Finally, we examine utilization of TMS excitability to guide targeted therapies and, through the use of repetitive TMS (rTMS), modulate cortical plasticity. EXPERT OPINION The examination of cortical hyperexcitability and plasticity with TMS has potential to optimize and expand the window of therapeutic interventions in AD, though remains at relatively early stage of development.
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Affiliation(s)
- Mehdi A J van den Bos
- Brain and Nerve Research Centre, Concord Repatriation General Hospital, Sydney, Australia
| | - Parvathi Menon
- Brain and Nerve Research Centre, Concord Repatriation General Hospital, Sydney, Australia
| | - Steve Vucic
- Brain and Nerve Research Centre, Concord Repatriation General Hospital, Sydney, Australia
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11
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Dubbioso R, Pellegrino G, Ranieri F, Di Pino G, Capone F, Dileone M, Iodice R, Ruggiero L, Tozza S, Uncini A, Manganelli F, Di Lazzaro V. BDNF polymorphism and inter hemispheric balance of motor cortex excitability: a preliminary study. J Neurophysiol 2021; 127:204-212. [PMID: 34936818 DOI: 10.1152/jn.00268.2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Preclinical studies have demonstrated that Brain-Derived Neurotrophic Factor (BDNF) plays a crucial role in the homeostatic regulation of cortical excitability and excitation/inhibition balance. Using transcranial magnetic stimulation (TMS) techniques we investigated whether BDNF polymorphism could influence cortical excitability of the left and right primary motor cortex in healthy humans. Twenty-nine participants were recruited and genotyped for the presence of the BDNF Val66Met polymorphism, namely homozygous for the valine allele (Val/Val), heterozygotes (Val/Met), and homozygous for the methionine allele (Met/Met). Blinded to the latter, we evaluated inhibitory and facilitatory circuits of the left (LH) and right motor cortex (RH) by measuring resting (RMT) and active motor threshold (AMT), short interval intracortical inhibition (SICI) and intracortical facilitation (ICF). For each neurophysiological metric we also considered the inter-hemispheric balance expressed by the Laterality Index (LI). Val/Val participants (n= 21) exhibited an overall higher excitability of the LH compared to the RH, as probed by lower motor thresholds, lower SICI and higher ICF. Val/Val participants displayed positive LI, especially for AMT and ICF (all p< 0.05), indicating higher LH excitability and more pronounced inter-hemispheric excitability imbalance as compared to Met carriers. Our preliminary results suggest that BDNF Val66Met polymorphism might influence interhemispheric balance of motor cortex excitability.
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Affiliation(s)
- Raffaele Dubbioso
- Department of Neurosciences, Reproductive Sciences and Odontostomatology, University of Naples "Federico II", Naples, Italy
| | - Giovanni Pellegrino
- Neurology and Neurosurgery Department, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Federico Ranieri
- Neurology Unit, Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Giovanni Di Pino
- Research Unit of Neurophysiology and Neuroengineering of Human-Technology Interaction (NeXTlab), Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy
| | - Fioravante Capone
- Unit of Neurology, Neurophysiology, Neurobiology, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy
| | - Michele Dileone
- Faculty of Health Sciences, University of Castilla La Mancha, Talavera de la Reina, Spain
| | - Rosa Iodice
- Department of Neurosciences, Reproductive Sciences and Odontostomatology, University of Naples "Federico II", Naples, Italy
| | - Lucia Ruggiero
- Department of Neurosciences, Reproductive Sciences and Odontostomatology, University of Naples "Federico II", Naples, Italy
| | - Stefano Tozza
- Department of Neurosciences, Reproductive Sciences and Odontostomatology, University of Naples "Federico II", Naples, Italy
| | - Antonino Uncini
- Department of Neuroscience, Imaging and Clinical Sciences, University "G. d'Annunzio", Chieti-Pescara, Italy
| | - Fiore Manganelli
- Department of Neurosciences, Reproductive Sciences and Odontostomatology, University of Naples "Federico II", Naples, Italy
| | - Vincenzo Di Lazzaro
- Unit of Neurology, Neurophysiology, Neurobiology, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy
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12
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Kornatz KW, Poston B, Stelmach GE. Age and Not the Preferred Limb Influences the Kinematic Structure of Pointing Movements. J Funct Morphol Kinesiol 2021; 6:jfmk6040100. [PMID: 34940509 PMCID: PMC8703669 DOI: 10.3390/jfmk6040100] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 12/02/2021] [Accepted: 12/04/2021] [Indexed: 12/02/2022] Open
Abstract
In goal-directed movements, effective open-loop control reduces the need for feedback-based corrective submovements. The purpose of this study was to determine the influence of hand preference and aging on submovements during single- and two-joint pointing movements. A total of 12 young and 12 older right-handed participants performed pointing movements that involved either elbow extension or a combination of elbow extension and horizontal shoulder flexion with their right and left arms to a target. Kinematics were used to separate the movements into their primary and secondary submovements. The older adults exhibited slower movements, used secondary submovements more often, and produced relatively shorter primary submovements. However, there were no interlimb differences for either age group or for the single- and two-joint movements. These findings indicate that open-loop control is similar between arms but compromised in older compared to younger adults.
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Affiliation(s)
- Kurt W. Kornatz
- Department of Exercise Physiology, Winston-Salem State University, Winston-Salem, NC 27110, USA;
| | - Brach Poston
- Department of Kinesiology and Nutrition Sciences, University of Nevada-Las Vegas, Las Vegas, NV 89154, USA
- Correspondence: ; Tel.: +1-702-895-5329
| | - George E. Stelmach
- Department of Kinesiology, Arizona State University, Tempe, AZ 85281, USA;
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Herbert P, Burke JR. Characterization of stimulus response curves obtained with transcranial magnetic stimulation from bilateral anterior digastric muscles in healthy subjects. Somatosens Mot Res 2021; 38:178-187. [PMID: 34126860 DOI: 10.1080/08990220.2021.1914019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
PURPOSE The purpose of the study was to describe measurements of stimulus-response curves in the anterior digastric muscle (ADM) bilaterally following transcranial magnetic stimulation (TMS) to the right and left hemispheres. The first dorsal interosseous muscle (FDI) was the control muscle. MATERIALS AND METHODS The subjects were 20 healthy young adults. Test sessions determined motor thresholds (MT) and stimulus-response curves (1.0, 1.2, 1.4, 1.6 × MT) from either the FDI or ADM following TMS to left and right hemispheres using the double cone coil. Bilateral recordings of MEPs in the left and right ADM allowed us to generate stimulus response curves following ipsilateral and contralateral TMS. RESULTS Intraclass correlation coefficients (ICC) for MEP amplitudes from ipsilateral and contralateral ADMs were >0.60 at motor threshold (MT) and >0.90 at stimulus intensities above MT. There was a linear increase in MEP amplitudes across stimulus intensities for the FDI following contralateral TMS, while MEP amplitudes from the ADM following contralateral and ipsilateral TMS increased linearly across stimulus intensities [F(3, 57) [Muscle × Recording Site × Stim Intensity] = 33.57; p < 0.05]; (ηp2 = 0.64). The slopes of the stimulus-response curve of the contralateral FDI was greater than the slopes of the stimulus response curves of the ipsilateral and contralateral ADM (p < 0.05). CONCLUSIONS The current study provided insights on the methodology for recording stimulus response curves in the ADM with TMS. These findings may translate into a valid, reliable, and relevant clinical outcome to study the pathophysiology of the corticobulbar motor system.
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Gaffney CJ, Drinkwater A, Joshi SD, O'Hanlon B, Robinson A, Sands KA, Slade K, Braithwaite JJ, Nuttall HE. Short-Term Immobilization Promotes a Rapid Loss of Motor Evoked Potentials and Strength That Is Not Rescued by rTMS Treatment. Front Hum Neurosci 2021; 15:640642. [PMID: 33981206 PMCID: PMC8107283 DOI: 10.3389/fnhum.2021.640642] [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: 12/11/2020] [Accepted: 03/01/2021] [Indexed: 11/23/2022] Open
Abstract
Short-term limb immobilization results in skeletal muscle decline, but the underlying mechanisms are incompletely understood. This study aimed to determine the neurophysiologic basis of immobilization-induced skeletal muscle decline, and whether repetitive Transcranial Magnetic Stimulation (rTMS) could prevent any decline. Twenty-four healthy young males (20 ± 0.5 years) underwent unilateral limb immobilization for 72 h. Subjects were randomized between daily rTMS (n = 12) using six 20 Hz pulse trains of 1.5 s duration with a 60 s inter-train-interval delivered at 90% resting Motor Threshold (rMT), or Sham rTMS (n = 12) throughout immobilization. Maximal grip strength, EMG activity, arm volume, and composition were determined at 0 and 72 h. Motor Evoked Potentials (MEPs) were determined daily throughout immobilization to index motor excitability. Immobilization induced a significant reduction in motor excitability across time (−30% at 72 h; p < 0.05). The rTMS intervention increased motor excitability at 0 h (+13%, p < 0.05). Despite daily rTMS treatment, there was still a significant reduction in motor excitability (−33% at 72 h, p < 0.05), loss in EMG activity (−23.5% at 72 h; p < 0.05), and a loss of maximal grip strength (−22%, p < 0.001) after immobilization. Interestingly, the increase in biceps (Sham vs. rTMS) (+0.8 vs. +0.1 mm, p < 0.01) and posterior forearm (+0.3 vs. +0.0 mm, p < 0.05) skinfold thickness with immobilization in Sham treatment was not observed following rTMS treatment. Reduced MEPs drive the loss of strength with immobilization. Repetitive Transcranial Magnetic Stimulation cannot prevent this loss of strength but further investigation and optimization of neuroplasticity protocols may have therapeutic benefit.
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Affiliation(s)
- Christopher J Gaffney
- Lancaster Medical School, Health Innovation One, Lancaster University, Lancaster, United Kingdom
| | - Amber Drinkwater
- Department of Psychology, Faculty of Science & Technology, Lancaster University, Lancaster, United Kingdom
| | - Shalmali D Joshi
- Department of Psychology, Faculty of Science & Technology, Lancaster University, Lancaster, United Kingdom
| | - Brandon O'Hanlon
- Department of Psychology, Faculty of Science & Technology, Lancaster University, Lancaster, United Kingdom
| | - Abbie Robinson
- Department of Psychology, Faculty of Science & Technology, Lancaster University, Lancaster, United Kingdom
| | - Kayle-Anne Sands
- Department of Psychology, Faculty of Science & Technology, Lancaster University, Lancaster, United Kingdom
| | - Kate Slade
- Department of Psychology, Faculty of Science & Technology, Lancaster University, Lancaster, United Kingdom
| | - Jason J Braithwaite
- Department of Psychology, Faculty of Science & Technology, Lancaster University, Lancaster, United Kingdom
| | - Helen E Nuttall
- Department of Psychology, Faculty of Science & Technology, Lancaster University, Lancaster, United Kingdom
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15
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Giuffre A, Zewdie E, Carlson HL, Wrightson JG, Kuo HC, Cole L, Kirton A. Robotic transcranial magnetic stimulation motor maps and hand function in adolescents. Physiol Rep 2021; 9:e14801. [PMID: 33817998 PMCID: PMC8020044 DOI: 10.14814/phy2.14801] [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: 02/17/2021] [Accepted: 02/24/2021] [Indexed: 12/31/2022] Open
Abstract
Introduction Transcranial magnetic stimulation (TMS) motor mapping can characterize the neurophysiology of the motor system. Limitations including human error and the challenges of pediatric populations may be overcome by emerging robotic systems. We aimed to show that neuronavigated robotic motor mapping in adolescents could efficiently produce discrete maps of individual upper extremity muscles, the characteristics of which would correlate with motor behavior. Methods Typically developing adolescents (TDA) underwent neuronavigated robotic TMS mapping of bilateral motor cortex. Representative maps of first dorsal interosseous (FDI), abductor pollicis brevis (APB), and abductor digiti minimi (ADM) muscles in each hand were created. Map features including area (primary), volume, and center of gravity were analyzed across different excitability regions (R100%, R75%, R50%, R25%). Correlations between map metrics and validated tests of hand motor function (Purdue Pegboard Test as primary) were explored. Results Twenty‐four right‐handed participants (range 12–18 years, median 15.5 years, 52% female) completed bilateral mapping and motor assessments with no serious adverse events or dropouts. Gender and age were associated with hand function and motor map characteristics. Full motor maps (R100%) for FDI did not correlate with motor function in either hand. Smaller excitability subset regions demonstrated reduced variance and dose‐dependent correlations between primary map variables and motor function in the dominant hemisphere. Conclusions Hand function in TDA correlates with smaller subset excitability regions of robotic TMS motor map outcomes. Refined motor maps may have less variance and greater potential to quantify interventional neuroplasticity. Robotic TMS mapping is safe and feasible in adolescents.
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Affiliation(s)
- Adrianna Giuffre
- Calgary Pediatric Stroke Program, Alberta Children's Hospital, Calgary, Alberta, Canada.,Department of Pediatrics, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Ephrem Zewdie
- Calgary Pediatric Stroke Program, Alberta Children's Hospital, Calgary, Alberta, Canada.,Department of Pediatrics, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Helen L Carlson
- Calgary Pediatric Stroke Program, Alberta Children's Hospital, Calgary, Alberta, Canada.,Department of Pediatrics, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - James G Wrightson
- Calgary Pediatric Stroke Program, Alberta Children's Hospital, Calgary, Alberta, Canada.,Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Hsing-Ching Kuo
- Department of Physical Medicine & Rehabilitation, University of California, Davis, CA, USA
| | - Lauran Cole
- Calgary Pediatric Stroke Program, Alberta Children's Hospital, Calgary, Alberta, Canada
| | - Adam Kirton
- Calgary Pediatric Stroke Program, Alberta Children's Hospital, Calgary, Alberta, Canada.,Department of Pediatrics, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
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16
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Garcia MAC, Nogueira-Campos AA, Moraes VH, Souza VH. Can Corticospinal Excitability Shed Light Into the Effects of Handedness on Motor Performance? FRONTIERS IN NEUROERGONOMICS 2021; 2:651501. [PMID: 38235226 PMCID: PMC10790861 DOI: 10.3389/fnrgo.2021.651501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Accepted: 03/01/2021] [Indexed: 01/19/2024]
Affiliation(s)
- Marco Antonio Cavalcanti Garcia
- Programa de Pós-Graduação em Ciências da Reabilitação e Desempenho Físico-Funcional, Faculdade de Fisioterapia, Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil
- Laboratório de Neurofisiologia Cognitiva (LabNeuro), Departamento de Fisiologia, Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil
- Grupo de Estudos em Neuro Biomecânica, Faculdade de Fisioterapia, Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil
- Núcleo de Pesquisas em Neurociências e Reabilitação Motora, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Anaelli Aparecida Nogueira-Campos
- Laboratório de Neurofisiologia Cognitiva (LabNeuro), Departamento de Fisiologia, Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil
- Grupo de Estudos em Neuro Biomecânica, Faculdade de Fisioterapia, Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil
| | - Victor Hugo Moraes
- Núcleo de Pesquisas em Neurociências e Reabilitação Motora, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Victor Hugo Souza
- Grupo de Estudos em Neuro Biomecânica, Faculdade de Fisioterapia, Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil
- Department of Neuroscience and Biomedical Engineering, Aalto University School of Science, Espoo, Finland
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17
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Botta F, Lupiáñez J, Santangelo V, Martín-Arévalo E. Transcranial Magnetic Stimulation of the Right Superior Parietal Lobule Modulates the Retro-Cue Benefit in Visual Short-Term Memory. Brain Sci 2021; 11:brainsci11020252. [PMID: 33670446 PMCID: PMC7922694 DOI: 10.3390/brainsci11020252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 02/10/2021] [Accepted: 02/10/2021] [Indexed: 11/16/2022] Open
Abstract
Several studies have shown enhanced performance in change detection tasks when spatial cues indicating the probe's location are presented after the memory array has disappeared (i.e., retro-cues) compared with spatial cues that are presented simultaneously with the test array (i.e., post-cues). This retro-cue benefit led some authors to propose the existence of two different stores of visual short-term memory: a weak but high-capacity store (fragile memory (FM)) linked to the effect of retro-cues and a robust but low-capacity store (working memory (WM)) linked to the effect of post-cues. The former is thought to be an attention-free system, whereas the latter would strictly depend on selective attention. Nonetheless, this dissociation is under debate, and several authors do not consider retro-cues as a proxy to measure the existence of an independent memory system (e.g., FM). We approached this controversial issue by altering the attention-related functions in the right superior parietal lobule (SPL) by transcranial magnetic stimulation (TMS), whose effects were mediated by the integrity of the right superior longitudinal fasciculus (SLF). Specifically, we asked whether TMS on the SPL affected the performance of retro cues vs. post-cues to a similar extent. The results showed that TMS on the SPL, mediated by right SLF-III integrity, produced a modulation of the retro-cue benefit, namely a memory capacity decrease in the post-cues but not in the retro-cues. These findings have strong implications for the debate on the existence of independent stages of visual short-term memory and for the growing literature showing a key role of the SLF for explaining the variability of TMS effects across participants.
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Affiliation(s)
- Fabiano Botta
- Department of Experimental Psychology and Mind, Brain, and Behavior Research Center (CIMCYC), University of Granada, 18011 Granada, Spain; (J.L.); (E.M.-A.)
- Correspondence:
| | - Juan Lupiáñez
- Department of Experimental Psychology and Mind, Brain, and Behavior Research Center (CIMCYC), University of Granada, 18011 Granada, Spain; (J.L.); (E.M.-A.)
| | - Valerio Santangelo
- Department of Philosophy, Social Sciences & Education, University of Perugia, 06123 Perugia, Italy;
- Neuroimaging Laboratory, IRCCS Santa Lucia Foundation, 00179 Rome, Italy
| | - Elisa Martín-Arévalo
- Department of Experimental Psychology and Mind, Brain, and Behavior Research Center (CIMCYC), University of Granada, 18011 Granada, Spain; (J.L.); (E.M.-A.)
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18
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Matsumoto T, Watanabe T, Kuwabara T, Yunoki K, Chen X, Kubo N, Kirimoto H. Excitability of the Ipsilateral Primary Motor Cortex During Unilateral Goal-Directed Movement. Front Hum Neurosci 2021; 15:617146. [PMID: 33679346 PMCID: PMC7925409 DOI: 10.3389/fnhum.2021.617146] [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: 10/14/2020] [Accepted: 01/28/2021] [Indexed: 11/13/2022] Open
Abstract
Introduction Previous transcranial magnetic stimulation (TMS) studies have revealed that the activity of the primary motor cortex ipsilateral to an active hand (ipsi-M1) plays an important role in motor control. The aim of this study was to investigate whether the ipsi-M1 excitability would be influenced by goal-directed movement and laterality during unilateral finger movements. Method Ten healthy right-handed subjects performed four finger tapping tasks with the index finger: (1) simple tapping (Tap) task, (2) Real-word task, (3) Pseudoword task, and (4) Visually guided tapping (VT) task. In the Tap task, the subject performed self-paced simple tapping on a touch screen. In the real-word task, the subject tapped letters displayed on the screen one by one to create a Real-word (e.g., apple). Because the action had a specific purpose (i.e., creating a word), this task was considered to be goal-directed as compared to the Tap task. In the Pseudoword task, the subject tapped the letters to create a pseudoword (e.g., gdiok) in the same manner as in the Real-word task; however, the word was less meaningful. In the VT task, the subject was required to touch a series of illuminated buttons. This task was considered to be less goal-directed than the Pseudoword task. The tasks were performed with the right and left hand, and a rest condition was added as control. Single- and paired-pulse TMS were applied to the ipsi-M1 to measure corticospinal excitability and short- and long-interval intracortical inhibition (SICI and LICI) in the resting first dorsal interosseous (FDI) muscle. Results We found the smaller SICI in the ipsi-M1 during the VT task compared with the resting condition. Further, both SICI and LICI were smaller in the right than in the left M1, regardless of the task conditions. Discussion We found that SICI in the ipsi-M1 is smaller during visual illumination-guided finger movement than during the resting condition. Our finding provides basic data for designing a rehabilitation program that modulates the M1 ipsilateral to the moving limb, for example, for post-stroke patients with severe hemiparesis.
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Affiliation(s)
- Takuya Matsumoto
- Department of Sensorimotor Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan.,Research Fellow of Japan Society for the Promotion of Science, Tokyo, Japan
| | - Tatsunori Watanabe
- Department of Sensorimotor Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Takayuki Kuwabara
- Department of Sensorimotor Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Keisuke Yunoki
- Department of Sensorimotor Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Xiaoxiao Chen
- Department of Sensorimotor Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Nami Kubo
- Department of Sensorimotor Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Hikari Kirimoto
- Department of Sensorimotor Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
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19
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Clinical and Electrophysiological Hints to TMS in De Novo Patients with Parkinson's Disease and Progressive Supranuclear Palsy. J Pers Med 2020. [PMID: 33322688 DOI: 10.3390/jpm10040274.] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Transcranial magnetic stimulation (TMS) can non-invasively probe cortical excitability in movement disorders, although clinical significance is still controversial, especially at early stages. We compare single-pulse TMS in two prototypic synucleinopathy and tauopathy-i.e., Parkinson's disease (PD) and Progressive Supranuclear Palsy (PSP), respectively-to find neurophysiological differences and identify early measures associated with cognitive impairment. METHODS 28 PD and 23 PSP de novo patients were age-matched with 28 healthy controls, all right-handed and drug-free. Amplitude and latency of motor evoked potentials (MEP), central motor conduction time, resting motor threshold (rMT), and cortical silent period (CSP) were recorded through a figure-of-eight coil from the First Dorsal Interosseous muscle (FDI), bilaterally. RESULTS Mini Mental Examination and Frontal Assessment Battery (FAB) scored worse in PSP; PD had worse FAB than controls. Higher MEP amplitude from right FDI in PD and PSP than controls was found, without difference between them. CSP was bilaterally longer in patients than controls, but similar between patient groups. A positive correlation between FAB and rMT was observed in PSP, bilaterally. CONCLUSIONS Despite the small sample size, PD and PSP might share, at early stage, a similar global electrocortical asset. rMT might detect and possibly predict cognitive deterioration in PSP.
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20
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Fisicaro F, Lanza G, Cantone M, Ferri R, Pennisi G, Nicoletti A, Zappia M, Bella R, Pennisi M. Clinical and Electrophysiological Hints to TMS in De Novo Patients with Parkinson's Disease and Progressive Supranuclear Palsy. J Pers Med 2020; 10:jpm10040274. [PMID: 33322688 PMCID: PMC7768400 DOI: 10.3390/jpm10040274] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 12/06/2020] [Accepted: 12/10/2020] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Transcranial magnetic stimulation (TMS) can non-invasively probe cortical excitability in movement disorders, although clinical significance is still controversial, especially at early stages. We compare single-pulse TMS in two prototypic synucleinopathy and tauopathy-i.e., Parkinson's disease (PD) and Progressive Supranuclear Palsy (PSP), respectively-to find neurophysiological differences and identify early measures associated with cognitive impairment. METHODS 28 PD and 23 PSP de novo patients were age-matched with 28 healthy controls, all right-handed and drug-free. Amplitude and latency of motor evoked potentials (MEP), central motor conduction time, resting motor threshold (rMT), and cortical silent period (CSP) were recorded through a figure-of-eight coil from the First Dorsal Interosseous muscle (FDI), bilaterally. RESULTS Mini Mental Examination and Frontal Assessment Battery (FAB) scored worse in PSP; PD had worse FAB than controls. Higher MEP amplitude from right FDI in PD and PSP than controls was found, without difference between them. CSP was bilaterally longer in patients than controls, but similar between patient groups. A positive correlation between FAB and rMT was observed in PSP, bilaterally. CONCLUSIONS Despite the small sample size, PD and PSP might share, at early stage, a similar global electrocortical asset. rMT might detect and possibly predict cognitive deterioration in PSP.
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Affiliation(s)
- Francesco Fisicaro
- Department of Biomedical and Biotechnological Sciences, University of Catania, Via Santa Sofia, 97-95123 Catania, Italy; (F.F.); (M.P.)
| | - Giuseppe Lanza
- Department of Surgery and Medical-Surgical Specialties, University of Catania, Via Santa Sofia, 78-95123 Catania, Italy;
- Department of Neurology IC, Oasi Research Institute-IRCCS, Via Conte Ruggero, 73-94018 Troina, Italy;
- Correspondence: ; Tel.: +39-095-3782448
| | - Mariagiovanna Cantone
- Department of Neurology, Sant’Elia Hospital, ASP Caltanissetta, Via Luigi Russo, 6-93100 Caltanissetta, Italy;
| | - Raffaele Ferri
- Department of Neurology IC, Oasi Research Institute-IRCCS, Via Conte Ruggero, 73-94018 Troina, Italy;
| | - Giovanni Pennisi
- Department of Surgery and Medical-Surgical Specialties, University of Catania, Via Santa Sofia, 78-95123 Catania, Italy;
| | - Alessandra Nicoletti
- Department of Medical and Surgical Sciences and Advanced Technologies, University of Catania, Via Santa Sofia, 87-95123 Catania, Italy; (A.N.); (M.Z.); (R.B.)
| | - Mario Zappia
- Department of Medical and Surgical Sciences and Advanced Technologies, University of Catania, Via Santa Sofia, 87-95123 Catania, Italy; (A.N.); (M.Z.); (R.B.)
| | - Rita Bella
- Department of Medical and Surgical Sciences and Advanced Technologies, University of Catania, Via Santa Sofia, 87-95123 Catania, Italy; (A.N.); (M.Z.); (R.B.)
| | - Manuela Pennisi
- Department of Biomedical and Biotechnological Sciences, University of Catania, Via Santa Sofia, 97-95123 Catania, Italy; (F.F.); (M.P.)
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21
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Davis NJ. Variance in cortical depth across the brain surface: Implications for transcranial stimulation of the brain. Eur J Neurosci 2020; 53:996-1007. [PMID: 32877015 DOI: 10.1111/ejn.14957] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Accepted: 08/20/2020] [Indexed: 01/12/2023]
Abstract
The distance between the surface of the scalp and the surface of the grey matter of the brain is a key factor in determining the effective dose of non-invasive brain stimulation for an individual person. The highly folded nature of the cortical surface means that the depth of a particular brain area is likely to vary between individuals. The question addressed here is: what is the variability of this measure of cortical depth? Ninety-four anatomical MRI images were taken from the OASIS database. For each image, the minimum distance from each point in the grey matter to the scalp surface was determined. Transforming these estimates into standard space meant that the coefficient of variation could be determined across the sample. The results indicated that depth variability is high across the cortical surface, even when taking sulcal depth into account. This was true even for the primary visual and motor areas, which are often used in setting TMS dosage. The correlation of the depth of these areas and the depth of other brain areas was low. The results suggest that dose setting of TMS based on visual or evoked potentials may offer poor reliability, and that individual brain images should be used when targeting non-primary brain areas.
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Affiliation(s)
- Nick J Davis
- Department of Psychology, Manchester Metropolitan University, Manchester, UK
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22
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Lyle KB, Grillo MC. Why are consistently-handed individuals more authoritarian? The role of need for cognitive closure. Laterality 2020; 25:490-510. [PMID: 32498598 DOI: 10.1080/1357650x.2020.1765791] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Recent studies indicate that individuals with consistent hand preference are more authoritarian than individuals whose preference is relatively inconsistent. We explored the role of epistemic needs in the handedness-authoritarianism relationship. Based on findings that consistent individuals are less cognitively flexible than inconsistent individuals, we hypothesized that consistent-handers would report greater need for definite knowledge. To measure this, we administered the revised Need for Cognitive Closure scale to a sample of undergraduates (N = 235), along with measures of handedness consistency and authoritarian submission. Consistent individuals scored significantly higher on authoritarian submission and need for closure. Need for closure fully mediated the relationship between consistency and submission. Consistent individuals also expressed greater prejudice against authoritarian out-groups such as immigrants and liberals. This effect was partially mediated by authoritarian submission. We theorize that consistent-handers' cognitive inflexibility leads them to covet definite knowledge. These individuals turn to authoritarianism because it promises to stifle dissent and protect existing (conventional) knowledge.
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Affiliation(s)
- Keith B Lyle
- Department of Psychological and Brain Sciences, University of Louisville, Louisville, KY, USA
| | - Michael C Grillo
- Department of Political Science, Schreiner University, Kerrville, TX, USA
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23
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Lee SH, Jin SH, An J. The difference in cortical activation pattern for complex motor skills: A functional near- infrared spectroscopy study. Sci Rep 2019; 9:14066. [PMID: 31575954 PMCID: PMC6773684 DOI: 10.1038/s41598-019-50644-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 09/16/2019] [Indexed: 11/23/2022] Open
Abstract
The human brain is lateralized to dominant or non-dominant hemispheres, and controlled through large-scale neural networks between correlated cortical regions. Recently, many neuroimaging studies have been conducted to examine the origin of brain lateralization, but this is still unclear. In this study, we examined the differences in brain activation in subjects according to dominant and non-dominant hands while using chopsticks. Fifteen healthy right-handed subjects were recruited to perform tasks which included transferring almonds using stainless steel chopsticks. Functional near-infrared spectroscopy (fNIRS) was used to acquire the hemodynamic response over the primary sensory-motor cortex (SM1), premotor area (PMC), supplementary motor area (SMA), and frontal cortex. We measured the concentrations of oxy-hemoglobin and deoxy-hemoglobin induced during the use of chopsticks with dominant and non-dominant hands. While using the dominant hand, brain activation was observed on the contralateral side. While using the non-dominant hand, brain activation was observed on the ipsilateral side as well as the contralateral side. These results demonstrate dominance and functional asymmetry of the cerebral hemisphere.
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Affiliation(s)
- Seung Hyun Lee
- Convergence Research Center for Wellness, DGIST, Daegu, Republic of Korea
| | - Sang Hyeon Jin
- Convergence Research Center for Wellness, DGIST, Daegu, Republic of Korea
| | - Jinung An
- Convergence Research Center for Wellness, DGIST, Daegu, Republic of Korea.
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24
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Chowdhury NS, Livesey EJ, Harris JA. Contralateral and Ipsilateral Relationships between Intracortical Inhibition and Stopping Efficiency. Neuroscience 2019; 415:10-17. [DOI: 10.1016/j.neuroscience.2019.07.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 06/26/2019] [Accepted: 07/03/2019] [Indexed: 11/29/2022]
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25
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Handedness Matters for Motor Control But Not for Prediction. eNeuro 2019; 6:ENEURO.0136-19.2019. [PMID: 31138661 PMCID: PMC6557034 DOI: 10.1523/eneuro.0136-19.2019] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2019] [Revised: 05/11/2019] [Accepted: 05/15/2019] [Indexed: 12/15/2022] Open
Abstract
Skilled motor behavior relies on the ability to control the body and to predict the sensory consequences of this control. Although there is ample evidence that manual dexterity depends on handedness, it remains unclear whether control and prediction are similarly impacted. To address this issue, right-handed human participants performed two tasks with either the right or the left hand. In the first task, participants had to move a cursor with their hand so as to track a target that followed a quasi-random trajectory. This hand-tracking task allowed testing the ability to control the hand along an imposed trajectory. In the second task, participants had to track with their eyes a target that was self-moved through voluntary hand motion. This eye-tracking task allowed testing the ability to predict the visual consequences of hand movements. As expected, results showed that hand tracking was more accurate with the right hand than with the left hand. In contrast, eye tracking was similar in terms of spatial and temporal gaze attributes whether the target was moved by the right or the left hand. Although these results extend previous evidence for different levels of control by the two hands, they show that the ability to predict the visual consequences of self-generated actions does not depend on handedness. We propose that the greater dexterity exhibited by the dominant hand in many motor tasks stems from advantages in control, not in prediction. Finally, these findings support the notion that prediction and control are distinct processes.
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26
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Martín-Arévalo E, Lupiáñez J, Narganes-Pineda C, Marino G, Colás I, Chica AB. The causal role of the left parietal lobe in facilitation and inhibition of return. Cortex 2019; 117:311-322. [PMID: 31185374 DOI: 10.1016/j.cortex.2019.04.025] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 04/12/2019] [Accepted: 04/30/2019] [Indexed: 11/26/2022]
Abstract
Following non-informative peripheral cues, responses are facilitated at the cued compared to the uncued location at short cue-target intervals. This effect reverses at longer intervals, giving rise to Inhibition of Return (IOR). The integration-segregation hypothesis (Lupiáñez, 2010) suggests that peripheral cues always produce an onset-detection cost regardless the behavioral cueing effect that is measured - either facilitation or IOR. In the present study, we used transcranial magnetic stimulation (TMS) to investigate the causal contribution of this detection cost to performance. We used a cueing paradigm with a target discrimination task that was preceded by a non-informative peripheral cue. The presence-absence of a central intervening event was manipulated. Online TMS to the left superior parietal lobe (compared to an active vertex stimulation) lead to an overall more positive effect (faster responses for cued as compared to uncued trials), by putatively impairing the detection cost contribution to performance. The data revealed a strong association between overall RT and the TMS effect, and also between overall RT and the integrity of the first branch of the left superior longitudinal fascicule. These results have critical implications not only for the open debate about the mechanism/s underlying spatial orienting effects, but also for the growing literature demonstrating that white matter connectivity is crucial for explaining inter-individual behavioral variability.
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Affiliation(s)
- E Martín-Arévalo
- Department of Experimental Psychology, and Mind, Brain, and Behavior Research Center (CIMCYC), University of Granada, Spain.
| | - J Lupiáñez
- Department of Experimental Psychology, and Mind, Brain, and Behavior Research Center (CIMCYC), University of Granada, Spain
| | - C Narganes-Pineda
- Department of Experimental Psychology, and Mind, Brain, and Behavior Research Center (CIMCYC), University of Granada, Spain
| | - G Marino
- Department of Experimental Psychology, and Mind, Brain, and Behavior Research Center (CIMCYC), University of Granada, Spain
| | - I Colás
- Department of Experimental Psychology, and Mind, Brain, and Behavior Research Center (CIMCYC), University of Granada, Spain
| | - Ana B Chica
- Department of Experimental Psychology, and Mind, Brain, and Behavior Research Center (CIMCYC), University of Granada, Spain
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27
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Nicolini C, Harasym D, Turco CV, Nelson AJ. Human motor cortical organization is influenced by handedness. Cortex 2019; 115:172-183. [PMID: 30826624 DOI: 10.1016/j.cortex.2019.01.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 10/29/2018] [Accepted: 01/10/2019] [Indexed: 11/28/2022]
Abstract
Although there is some evidence that handedness is associated with structural and functional differences in the motor cortex, findings remain inconclusive. Here, we evaluated whether handedness influences the location, size and overlap of the cortical representations of upper limb muscles across hemispheres in right- versus left-handed individuals. Using transcranial magnetic stimulation, the cortical representations of abductor pollicis brevis, flexor carpi radialis and biceps brachii muscles were mapped bilaterally with a 6 by 5 grid space. Results indicate that right-handers had more lateral and posterior representations in the non-dominant hemisphere as well as greater overall cortical territory compared to left-handers. Right- and left-handers did not differ in the extent of overlap between muscle representations. Our findings suggest that human motor cortical organization of upper limb muscles is indeed influenced by handedness, specifically with regard to the location of non-dominant cortical muscle representations and the size of cortical territory dedicated to upper limb muscle representations.
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Affiliation(s)
- Chiara Nicolini
- Department of Kinesiology, McMaster University, Hamilton, ON, Canada.
| | - Diana Harasym
- School of Biomedical Engineering, McMaster University, Hamilton, ON, Canada.
| | - Claudia V Turco
- Department of Kinesiology, McMaster University, Hamilton, ON, Canada.
| | - Aimee J Nelson
- Department of Kinesiology, McMaster University, Hamilton, ON, Canada; School of Biomedical Engineering, McMaster University, Hamilton, ON, Canada.
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28
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Lim H, Ku J. Multiple-command single-frequency SSVEP-based BCI system using flickering action video. J Neurosci Methods 2019; 314:21-27. [PMID: 30659844 DOI: 10.1016/j.jneumeth.2019.01.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 01/15/2019] [Accepted: 01/15/2019] [Indexed: 10/27/2022]
Abstract
BACKGROUND The number of commands in a brain-computer interface (BCI) system is important. This study proposes a new BCI technique to increase the number of commands in a single BCI system without loss of accuracy. NEW METHOD We expected that a flickering action video with left and right elbow movements could simultaneously activate the different pattern of event-related desynchronization (ERD) according to the video contents (e.g., left or right) and steady-state visually evoked potential (SSVEP). The classification accuracy to discriminate left, right, and rest states was compared under the three following feature combinations: SSVEP power (19-21 Hz), Mu power (8-13 Hz), and simultaneous SSVEP and Mu power. RESULTS The SSVEP feature could discriminate the stimulus condition, regardless of left or right, from the rest condition, while the Mu feature discriminated left or right, but was relatively poor in discriminating stimulus from rest. However, combining the SSVEP and Mu features, which were evoked by the stimulus with a single frequency, showed superior performance for discriminating all the stimuli among rest, left, or right. COMPARISON WITH THE EXISTING METHOD The video contents could activate the ERD differently, and the flickering component increased its accuracy, such that it revealed a better performance to discriminate when considering together. CONCLUSIONS This paradigm showed possibility of increasing performance in terms of accuracy and number of commands with a single frequency by applying flickering action video paradigm and applicability to rehabilitation systems used by patients to facilitate their mirror neuron systems while training.
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Affiliation(s)
- Hyunmi Lim
- Department of Biomedical Engineering, College of Medicine, Keimyung University, South Korea
| | - Jeonghun Ku
- Department of Biomedical Engineering, College of Medicine, Keimyung University, South Korea.
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29
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Temporal Profile and Limb-specificity of Phasic Pain-Evoked Changes in Motor Excitability. Neuroscience 2018; 386:240-255. [DOI: 10.1016/j.neuroscience.2018.06.039] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 06/20/2018] [Accepted: 06/24/2018] [Indexed: 12/17/2022]
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30
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Poole BJ, Mather M, Livesey EJ, Harris IM, Harris JA. Motor-evoked potentials reveal functional differences between dominant and non-dominant motor cortices during response preparation. Cortex 2018. [PMID: 29533856 DOI: 10.1016/j.cortex.2018.02.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Transcranial magnetic stimulation (TMS) of the motor cortex produces motor-evoked potentials (MEPs) in contralateral muscles. The amplitude of these MEPs can be used to measure the excitability of the corticospinal tract during motor planning. In two experiments, we investigated learning-related changes in corticospinal excitability as subjects prepared to respond in a choice reaction-time task. Subjects responded with their left or right hand to a left or right arrow, and on some trials the arrow was immediately preceded by a warning cue that signaled which response would be required. TMS was applied to the motor cortex during the warning cues, and MEPs were measured in the dominant or non-dominant hand. We observed changes in corticospinal excitability during the warning cue, but these depended on which hand the subject was preparing to respond with, and how experienced they were with the task. When subjects prepared to respond with the non-dominant hand, excitability increased in the non-dominant hemisphere and decreased in the dominant hemisphere. These changes became stronger with task experience, and were accompanied by behavioral improvements in the task. When subjects were preparing a dominant-hand response, the non-dominant hemisphere was suppressed, but this effect disappeared as subjects gained experience with the task. There were no changes in the dominant hemisphere before dominant-hand responses. We conclude that preparing to respond with the non-dominant hand involves temporarily reversing an asymmetry in excitability that normally favors the dominant hemisphere, and that this pattern is enhanced by learning during the task.
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Affiliation(s)
| | - Marius Mather
- School of Psychology, University of Sydney, Australia
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31
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Souza VH, Baffa O, Garcia MAC. Lateralized asymmetries in distribution of muscular evoked responses: An evidence of specialized motor control over an intrinsic hand muscle. Brain Res 2018; 1684:60-66. [PMID: 29408387 DOI: 10.1016/j.brainres.2018.01.031] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 01/05/2018] [Accepted: 01/23/2018] [Indexed: 12/14/2022]
Abstract
Lateralized neural control over hand muscles has been associated with anatomical and physiological asymmetries in the central nervous system. Some studies suggested that the dominant cerebral hemisphere exhibit larger cortical representation areas with lower excitability, while others reported higher cortical excitability in dominant side compared to the contralateral, or even could not find any differences. Thus, neurophysiological lateral asymmetries are still controversial. This study aimed to evaluate differences in dominant and non-dominant sides in motor evoked potentials (MEPs) distribution and investigate whether conventional montages and high-density surface electromyography (HD-sEMG) provide reliable measurements of corticospinal excitability. MEPs elicited by transcranial magnetic stimulation (TMS) were recorded from dominant and non-dominant sides of healthy right-handed participants with an electrode grid over the abductor pollicis brevis muscle. MEPs amplitude distribution, amplitude, latency and resting motor threshold (MT) were evaluated. MEPs distribution significantly shifted towards the lateral direction on the dominant side. MT, amplitude, and latency did not reveal any asymmetries in functional cortical excitability. MEPs amplitude and latency were different for conventional montages and HD-sEMG. Our results suggest that laterality asymmetries manifest in both levels of cortical representation and muscle recruitment, possibly leading to a more pronounced abduction movement on dominant hemisphere compared to the non-dominant side in right-handers. Furthermore, the use of HD-sEMG provided additional insights over conventional electrode montages. A better understanding of laterality asymmetries in fine motor control may help to establish specialized treatments in sensory motor disorders patients.
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Affiliation(s)
- Victor Hugo Souza
- Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo. Av. Bandeirantes, 3900, CEP: 14040-901, Monte Alegre, Ribeirão Preto, SP, Brazil.
| | - Oswaldo Baffa
- Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo. Av. Bandeirantes, 3900, CEP: 14040-901, Monte Alegre, Ribeirão Preto, SP, Brazil.
| | - Marco A C Garcia
- Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo. Av. Bandeirantes, 3900, CEP: 14040-901, Monte Alegre, Ribeirão Preto, SP, Brazil; Departamento de Biociências e Atividades Físicas, Escola de Educação Física e Desportos, Universidade Federal do Rio de Janeiro. Av. Carlos Chagas Filho, 540, CEP: 21941-599, Cidade Universitária, Rio de Janeiro, RJ, Brazil; Laboratório de Neurobiologia II, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro. Av. Carlos Chagas Filho, 373, CEP: 21941-902, Cidade Universitária, Rio de Janeiro, RJ, Brazil.
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32
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Martín-Arévalo E, Schintu S, Farnè A, Pisella L, Reilly KT. Adaptation to Leftward Shifting Prisms Alters Motor Interhemispheric Inhibition. Cereb Cortex 2018; 28:528-537. [PMID: 27993820 PMCID: PMC6248503 DOI: 10.1093/cercor/bhw386] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 11/15/2016] [Accepted: 11/17/2016] [Indexed: 11/14/2022] Open
Abstract
Adaptation to rightward shifting prisms (rightward prism adaptation, RPA) ameliorates neglect symptoms in patients while adaptation to leftward shifting prisms (leftward prism adaptation, LPA) induces neglect-like behaviors in healthy subjects. It has been hypothesized that prism adaptation (PA) modulates interhemispheric balance between the parietal cortices by inhibiting the posterior parietal cortex (PPC) contralateral to the prismatic deviation, but PA's effects on interhemispheric inhibition (IHI) have not been directly investigated. Since there are hyper-excitable connections between the PPC and primary motor cortex (M1) in the left hemisphere of neglect patients, we reasoned that LPA might mimic right hemisphere lesions by reducing parietal IHI, hyper-exciting the left PPC and PPC-M1 connections, and in turn altering IHI at the motor level. Namely, we hypothesized that LPA would increase IHI from the left to the right M1. We examined changes in left-to-right and right-to-left IHI between the 2 M1s using the ipsilateral silent period (iSP) (Meyer et al. 1995) before and after either LPA or RPA. The iSP was significantly longer after LPA but only from left-to-right and it did not change at all after RPA. This is the first physiological demonstration that LPA alters IHI in the healthy brain.
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Affiliation(s)
- Elisa Martín-Arévalo
- ImpAct team, Lyon Neuroscience Research Center, INSERM
U1028, CRNS-UMR5292, 16 Ave. Doyen Lépine, 69676 Bron
Cedex, France
- Lyon 1 University, F-69373 Lyon, France
| | - Selene Schintu
- ImpAct team, Lyon Neuroscience Research Center, INSERM
U1028, CRNS-UMR5292, 16 Ave. Doyen Lépine, 69676 Bron
Cedex, France
- Lyon 1 University, F-69373 Lyon, France
- Behavioral Neurology Unit, National Institute of
Neurological Disorders and Stroke, National Institutes of Health,
10 Center Bethesda, MD, USA
| | - Alessandro Farnè
- ImpAct team, Lyon Neuroscience Research Center, INSERM
U1028, CRNS-UMR5292, 16 Ave. Doyen Lépine, 69676 Bron
Cedex, France
- Lyon 1 University, F-69373 Lyon, France
- Hospices Civils de Lyon, Neuro-immersion & Mouvement
et Handicap, F-69676 Lyon, France
| | - Laure Pisella
- ImpAct team, Lyon Neuroscience Research Center, INSERM
U1028, CRNS-UMR5292, 16 Ave. Doyen Lépine, 69676 Bron
Cedex, France
- Lyon 1 University, F-69373 Lyon, France
| | - Karen T Reilly
- ImpAct team, Lyon Neuroscience Research Center, INSERM
U1028, CRNS-UMR5292, 16 Ave. Doyen Lépine, 69676 Bron
Cedex, France
- Lyon 1 University, F-69373 Lyon, France
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33
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Hiraoka K, Igawa K, Kashiwagi M, Nakahara C, Oshima Y, Takakura Y. The laterality of stop and go processes of the motor response in left-handed and right-handed individuals. Laterality 2017; 23:51-66. [PMID: 28378624 DOI: 10.1080/1357650x.2017.1311906] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The objective of the present study was to investigate whether the stop and go processes of the motor response are asymmetrical and whether the asymmetries are dependent on handedness and the response selection process that is engaged. Both right-handed and left-handed participants abducted either the left or right index finger in response to an imperative cue in the choice reaction time (choice RT) or the simple RT task. A stop cue was presented after the imperative cue with a probability of .25. When the stop cue was presented, the participants withheld the prepared response. On the choice RT task, left-handed participants had significantly shorter RT and stop signal reaction time (SSRT) with the left versus the right hand, whereas right-handers showed no difference between hands on either measure. In the simple RT task, the RT and SSRT were not significantly different between the groups or the response sides. These results indicate that both the stop and go processes of the prepared left-hand response are completed earlier than those of the right-hand response in left-handed individuals when the stimulus-response process involves a response selection process.
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Affiliation(s)
- Koichi Hiraoka
- a College of Health and Human Sciences , Osaka Prefecture University , Habikino , Japan
| | - Kyudo Igawa
- a College of Health and Human Sciences , Osaka Prefecture University , Habikino , Japan
| | - Mina Kashiwagi
- a College of Health and Human Sciences , Osaka Prefecture University , Habikino , Japan
| | - Chisato Nakahara
- a College of Health and Human Sciences , Osaka Prefecture University , Habikino , Japan
| | - Yuki Oshima
- a College of Health and Human Sciences , Osaka Prefecture University , Habikino , Japan
| | - Yu Takakura
- a College of Health and Human Sciences , Osaka Prefecture University , Habikino , Japan
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Sollmann N, Bulubas L, Tanigawa N, Zimmer C, Meyer B, Krieg SM. The variability of motor evoked potential latencies in neurosurgical motor mapping by preoperative navigated transcranial magnetic stimulation. BMC Neurosci 2017; 18:5. [PMID: 28049425 PMCID: PMC5209850 DOI: 10.1186/s12868-016-0321-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2016] [Accepted: 12/09/2016] [Indexed: 12/19/2022] Open
Abstract
Background Recording of motor evoked potentials (MEPs) is used during navigated transcranial magnetic stimulation (nTMS) motor mapping to locate motor function in the human brain. However, factors potentially underlying MEP latency variability in neurosurgical motor mapping are vastly unknown. In the context of this study, one hundred brain tumor patients underwent preoperative nTMS-based motor mapping of the tumor hemisphere between 2010 and 2013. Fourteen predefined predictor variables were recorded, and MEP latencies of abductor pollicis brevis muscle (APB), abductor digiti minimi muscle (ADM), and flexor carpi radialis muscle (FCR) were analyzed using linear mixed-effect multiple regression analysis with the forward step-wise model comparison approach. Results Common factors (relevant to APB, ADM, and FCR) for MEP latency variability were gender, most likely due to body height, and antiepileptic drug (AED) intake. Muscle-specific factors (relevant to APB, ADM, or FCR) for MEP latency variability were resting motor threshold (rMT), tumor side, and tumor location. Conclusions Based on a large cohort of neurosurgical patients, this study provides data on a wide range of clinical factors that may underlie MEP latency variability. The factors that significantly contributed to MEP latency variability should be standardly recorded and taken into consideration during neurosurgical motor mapping.
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Affiliation(s)
- Nico Sollmann
- Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany.,TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Lucia Bulubas
- Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany.,TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Noriko Tanigawa
- Faculty of Linguistics, Philology, and Phonetics, University of Oxford, Walton Street, Oxford, OX1 2HG, UK
| | - Claus Zimmer
- TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.,Section of Neuroradiology, Department of Radiology, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany
| | - Bernhard Meyer
- Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany
| | - Sandro M Krieg
- Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany. .,TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.
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Shibuya K, Park SB, Howells J, Huynh W, Noto YI, Shahrizaila N, Matamala JM, Vucic S, Kiernan MC. Laterality of motor cortical function measured by transcranial magnetic stimulation threshold tracking. Muscle Nerve 2016; 55:424-427. [PMID: 27511622 DOI: 10.1002/mus.25372] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/08/2016] [Indexed: 12/12/2022]
Abstract
INTRODUCTION Threshold tracking paired-pulse transcranial magnetic stimulation (TTTMS) examines cortical function and is useful for diagnosis of motor neuron disorders. Differences in cortical function have been identified between dominant and non-dominant limbs using constant stimulus methods, but they remain unclear, potentially due to methodological differences. In this study we aimed to clarify differences in cortical function between dominant and non-dominant limbs using TTTMS. METHODS Single-pulse TMS, TTTMS, and nerve conduction studies were performed in 25 healthy, right-handed participants by recording from the abductor pollicis brevis muscle. RESULTS There were no side-to-side differences observed in resting motor threshold, motor evoked potential (MEP) amplitude, MEP latency, central motor conduction time, cortical silent period, short-interval intracortical inhibition and facilitation, compound muscle action potential (CMAP) amplitude, CMAP latency, F-wave latency, or neurophysiological index. CONCLUSIONS These findings suggest that, when using TTTMS, there are no differences in cortical function between dominant and non-dominant hemispheres. Muscle Nerve 55: 424-427, 2017.
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Affiliation(s)
- Kazumoto Shibuya
- Brain and Mind Centre, Sydney Medical School, University of Sydney, 94 Mallett Street, Camperdown, Sydney, New South Wales, 2050, Australia
| | - Susanna B Park
- Brain and Mind Centre, Sydney Medical School, University of Sydney, 94 Mallett Street, Camperdown, Sydney, New South Wales, 2050, Australia
| | - James Howells
- Brain and Mind Centre, Sydney Medical School, University of Sydney, 94 Mallett Street, Camperdown, Sydney, New South Wales, 2050, Australia
| | - William Huynh
- Brain and Mind Centre, Sydney Medical School, University of Sydney, 94 Mallett Street, Camperdown, Sydney, New South Wales, 2050, Australia.,Prince of Wales Clinical School, University of New South Wales, Sydney, Australia
| | - Yu-Ichi Noto
- Brain and Mind Centre, Sydney Medical School, University of Sydney, 94 Mallett Street, Camperdown, Sydney, New South Wales, 2050, Australia
| | - Nortina Shahrizaila
- Brain and Mind Centre, Sydney Medical School, University of Sydney, 94 Mallett Street, Camperdown, Sydney, New South Wales, 2050, Australia
| | - José M Matamala
- Brain and Mind Centre, Sydney Medical School, University of Sydney, 94 Mallett Street, Camperdown, Sydney, New South Wales, 2050, Australia
| | - Steve Vucic
- Westmead Clinical School, University of Sydney, Sydney, New South Wales, Australia
| | - Matthew C Kiernan
- Brain and Mind Centre, Sydney Medical School, University of Sydney, 94 Mallett Street, Camperdown, Sydney, New South Wales, 2050, Australia
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ter Braack EM, Koopman AWE, van Putten MJ. Early TMS evoked potentials in epilepsy: A pilot study. Clin Neurophysiol 2016; 127:3025-3032. [DOI: 10.1016/j.clinph.2016.06.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Revised: 05/31/2016] [Accepted: 06/03/2016] [Indexed: 11/16/2022]
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Li X, He W, Li C, Wang YC, Slavens BA, Zhou P. Motor unit number index examination in dominant and non-dominant hand muscles. Laterality 2015; 20:699-710. [PMID: 26227495 DOI: 10.1080/1357650x.2015.1041971] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
This study investigated the effect of handedness on motor unit number index (MUNIX). Maximal hand strength, compound muscle action potential (CMAP) and voluntary surface electromyography (EMG) signals were measured bilaterally for the first dorsal interosseous (FDI) and thenar muscles in 24 right-handed and 2 left-handed healthy subjects. Mean (±standard error) grip and pinch forces in the dominant hand were 43.99 ± 2.36 kg and 9.36 ± 0.52 kg respectively, significantly larger than those in the non-dominant hand (grip: 41.37 ± 2.29 kg, p < .001; pinch: 8.79 ± 0.46 kg, p < .01). Examination of myoelectric parameters did not show a significant difference among the CMAP area, the MUNIX or motor unit size index (MUSIX) between the two sides in the FDI and thenar muscles. In addition, there was a lack of correlation between the strength and myoelectric parameters in regression analysis. However, strong correlations were observed between dominant and non-dominant hand muscles in both strength and myoelectric measures. Our results indicate that the population of motor units or spinal motor neurons as estimated from MUNIX may not be associated with handedness. Such findings help understand and interpret the MUNIX during its application for clinical or laboratory investigations.
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Affiliation(s)
- Xiaoyan Li
- a Department of Physical Medicine and Rehabilitation , University of Texas Health Science Center at Houston, and TIRR Memorial Hermann Research Center , Houston , TX , USA
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Rossini PM, Burke D, Chen R, Cohen LG, Daskalakis Z, Di Iorio R, Di Lazzaro V, Ferreri F, Fitzgerald PB, George MS, Hallett M, Lefaucheur JP, Langguth B, Matsumoto H, Miniussi C, Nitsche MA, Pascual-Leone A, Paulus W, Rossi S, Rothwell JC, Siebner HR, Ugawa Y, Walsh V, Ziemann U. Non-invasive electrical and magnetic stimulation of the brain, spinal cord, roots and peripheral nerves: Basic principles and procedures for routine clinical and research application. An updated report from an I.F.C.N. Committee. Clin Neurophysiol 2015; 126:1071-1107. [PMID: 25797650 PMCID: PMC6350257 DOI: 10.1016/j.clinph.2015.02.001] [Citation(s) in RCA: 1772] [Impact Index Per Article: 196.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Revised: 01/22/2015] [Accepted: 02/01/2015] [Indexed: 12/14/2022]
Abstract
These guidelines provide an up-date of previous IFCN report on “Non-invasive electrical and magnetic stimulation of the brain, spinal cord and roots: basic principles and procedures for routine clinical application” (Rossini et al., 1994). A new Committee, composed of international experts, some of whom were in the panel of the 1994 “Report”, was selected to produce a current state-of-the-art review of non-invasive stimulation both for clinical application and research in neuroscience. Since 1994, the international scientific community has seen a rapid increase in non-invasive brain stimulation in studying cognition, brain–behavior relationship and pathophysiology of various neurologic and psychiatric disorders. New paradigms of stimulation and new techniques have been developed. Furthermore, a large number of studies and clinical trials have demonstrated potential therapeutic applications of non-invasive brain stimulation, especially for TMS. Recent guidelines can be found in the literature covering specific aspects of non-invasive brain stimulation, such as safety (Rossi et al., 2009), methodology (Groppa et al., 2012) and therapeutic applications (Lefaucheur et al., 2014). This up-dated review covers theoretical, physiological and practical aspects of non-invasive stimulation of brain, spinal cord, nerve roots and peripheral nerves in the light of more updated knowledge, and include some recent extensions and developments.
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Affiliation(s)
- P M Rossini
- Institute of Neurology, Department of Geriatrics, Neuroscience and Orthopedics, Catholic University, Policlinic A. Gemelli, Rome, Italy
| | - D Burke
- Department of Neurology, Royal Prince Alfred Hospital, University of Sydney, Sydney, Australia
| | - R Chen
- Division of Neurology, Toronto Western Research Institute, University of Toronto, Toronto, Ontario, Canada
| | - L G Cohen
- Human Cortical Physiology and Neurorehabilitation Section, NINDS, NIH, Bethesda, MD, USA
| | - Z Daskalakis
- Temerty Centre for Therapeutic Brain Intervention, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada
| | - R Di Iorio
- Institute of Neurology, Department of Geriatrics, Neuroscience and Orthopedics, Catholic University, Policlinic A. Gemelli, Rome, Italy.
| | - V Di Lazzaro
- Department of Neurology, University Campus Bio-medico, Rome, Italy
| | - F Ferreri
- Department of Neurology, University Campus Bio-medico, Rome, Italy; Department of Clinical Neurophysiology, University of Eastern Finland, Kuopio, Finland
| | - P B Fitzgerald
- Monash Alfred Psychiatry Research Centre, Monash University Central Clinical School and The Alfred, Melbourne, Australia
| | - M S George
- Medical University of South Carolina, Ralph H. Johnson VA Medical Center, Charleston, SC, USA
| | - M Hallett
- Human Motor Control Section, Medical Neurology Branch, NINDS, NIH, Bethesda, MD, USA
| | - J P Lefaucheur
- Department of Physiology, Henri Mondor Hospital, Assistance Publique - Hôpitaux de Paris, Créteil, France; EA 4391, Nerve Excitability and Therapeutic Team, Faculty of Medicine, Paris Est Créteil University, Créteil, France
| | - B Langguth
- Department of Psychiatry and Psychotherapy, University of Regensburg, Regensburg, Germany
| | - H Matsumoto
- Department of Neurology, Japanese Red Cross Medical Center, Tokyo, Japan
| | - C Miniussi
- Department of Clinical and Experimental Sciences University of Brescia, Brescia, Italy; IRCCS Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy
| | - M A Nitsche
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Georg-August-University, Göttingen, Germany
| | - A Pascual-Leone
- Berenson-Allen Center for Non-invasive Brain Stimulation, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - W Paulus
- Department of Clinical Neurophysiology, Georg-August University, Göttingen, Germany
| | - S Rossi
- Brain Investigation & Neuromodulation Lab, Unit of Neurology and Clinical Neurophysiology, Department of Neuroscience, University of Siena, Siena, Italy
| | - J C Rothwell
- Institute of Neurology, University College London, London, United Kingdom
| | - H R Siebner
- Department of Neurology, Copenhagen University Hospital Bispebjerg, Copenhagen, Denmark; Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
| | - Y Ugawa
- Department of Neurology, School of Medicine, Fukushima Medical University, Fukushima, Japan
| | - V Walsh
- Institute of Cognitive Neuroscience, University College London, London, United Kingdom
| | - U Ziemann
- Department of Neurology & Stroke, and Hertie Institute for Clinical Brain Research, Eberhard Karls University, Tübingen, Germany
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Kasuga S, Matsushika Y, Kasashima-Shindo Y, Kamatani D, Fujiwara T, Liu M, Ushiba J. Transcranial direct current stimulation enhances mu rhythm desynchronization during motor imagery that depends on handedness. Laterality 2015; 20:453-68. [PMID: 25599261 DOI: 10.1080/1357650x.2014.998679] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Transcranial direct current stimulation (tDCS) can modulate the amplitude of event-related desynchronization (ERD) that appears on the electroencephalogram (EEG) during motor imagery. To study the effect of handedness on the modulating effect of tDCS, we compared the difference in tDCS-boosted ERD during dominant and non-dominant hand motor imagery. EEGs were recorded over the left sensorimotor cortex of seven healthy right-handed volunteers, and we measured ERD induced either by dominant or non-dominant hand motor imagery. Ten minutes of anodal tDCS was then used to increase the cortical excitability of the contralateral primary motor cortex (M1), and ERD was measured again. With anodal tDCS, we observed only a small increase in ERD during non-dominant hand motor imagery, whereas the same stimulation induced a prominent increase in ERD during dominant hand motor imagery. This trend was most obvious in the participants who used their dominant hand more frequently. Although our study is preliminary because of a small sample size, these results suggest that the increase in ERD by applying anodal tDCS was stronger on the dominant side than on the non-dominant side. The background excitability of M1 may determine the strength of the effect of anodal tDCS on ERD by hand motor imagery.
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Affiliation(s)
- Shoko Kasuga
- a Department of Biosciences and Informatics, Faculty of Science and Technology , Keio University , Yokohama , Japan
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Philpott DT, Pearcey GE, Forman D, Power KE, Button DC. Chronic resistance training enhances the spinal excitability of the biceps brachii in the non-dominant arm at moderate contraction intensities. Neurosci Lett 2015; 585:12-6. [DOI: 10.1016/j.neulet.2014.11.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Revised: 11/04/2014] [Accepted: 11/08/2014] [Indexed: 11/30/2022]
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Ibey RJ, Bolton DAE, Buick AR, Staines WR, Carson RG. Interhemispheric inhibition of corticospinal projections to forearm muscles. Clin Neurophysiol 2014; 126:1934-40. [PMID: 25561164 DOI: 10.1016/j.clinph.2014.12.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 11/26/2014] [Accepted: 12/06/2014] [Indexed: 01/03/2023]
Abstract
OBJECTIVE Interhemispheric inhibition (IHI) is typically examined via responses elicited in intrinsic hand muscles. As the cortical representations of proximal and distal muscles in the upper limb are distinguished in terms of their inter-hemispheric projections, we sought to determine whether the IHI parameters established for the hand apply more generally. METHODS We investigated IHI at 5 different conditioning stimulus (CS) intensities and a range of short-latency inter-stimulus intervals (ISIs) in healthy participants. Conditioning and test stimuli were delivered over the M1 representation of the right and left flexor carpi radialis respectively. RESULTS IHI increased as a function of CS intensity, and was present for ISIs between 7 and 15ms. Inhibition was most pronounced for the 10ms ISI at all CS intensities. CONCLUSIONS The range of parameters for which IHI is elicited in projections to the forearm is similar to that reported for the hand. The specific utility lies in delineation of stimulus parameters that permit both potentiation and attenuation of IHI to be assessed. SIGNIFICANCE In light of evidence that there is a greater density of callosal projections between cortical areas that represent proximal muscles than between those corresponding to distal limb muscles, and in view of the assumption that variations in functional connectivity to which such differences give rise may have important implications for motor behavior, it is critical to determine whether processes mediating the expression of IHI depend on the effector that is studied. This issue is of further broad significance given the practical utility of movements generated by muscles proximal to the wrist in the context of upper limb rehabilitation.
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Affiliation(s)
- R J Ibey
- Department of Kinesiology, University of Waterloo, Waterloo, Canada
| | - D A E Bolton
- School of Psychology, Queen's University Belfast, Northern Ireland, UK.
| | - A R Buick
- School of Psychology, Queen's University Belfast, Northern Ireland, UK
| | - W R Staines
- Department of Kinesiology, University of Waterloo, Waterloo, Canada
| | - R G Carson
- School of Psychology, Queen's University Belfast, Northern Ireland, UK; Trinity College Institute of Neuroscience and School of Psychology, Trinity College Dublin, Ireland
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42
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Kuppuswamy A, Clark EV, Turner IF, Rothwell JC, Ward NS. Post-stroke fatigue: a deficit in corticomotor excitability? ACTA ACUST UNITED AC 2014; 138:136-48. [PMID: 25367024 DOI: 10.1093/brain/awu306] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
The pathophysiology of post-stroke fatigue is poorly understood although it is thought to be a consequence of central nervous system pathophysiology. In this study we investigate the relationship between corticomotor excitability and self-reported non-exercise related fatigue in chronic stroke population. Seventy first-time non-depressed stroke survivors (60.36 ± 12.4 years, 20 females, 56.81 ± 63 months post-stroke) with minimal motor and cognitive impairment were included in the cross-sectional observational study. Fatigue was measured using two validated questionnaires: Fatigue Severity Scale 7 and Neurological Fatigue Index - Stroke. Perception of effort was measured using a 0-10 numerical rating scale in an isometric biceps hold-task and was used as a secondary measure of fatigue. Neurophysiological measures of corticomotor excitability were performed using transcranial magnetic stimulation. Corticospinal excitability was quantified using resting and active motor thresholds and stimulus-response curves of the first dorsal interosseous muscle. Intracortical M1 excitability was measured using paired pulse paradigms: short and long interval intracortical inhibition in the same hand muscle as above. Excitability of cortical and subcortical inputs that drive M1 output was measured in the biceps muscle using a modified twitch interpolation technique to provide an index of central activation failure. Stepwise regression was performed to determine the explanatory variables that significantly accounted for variance in the fatigue and perception scores. Resting motor threshold (R = 0.384; 95% confidence interval = 0.071; P = 0.036) accounted for 14.7% (R(2)) of the variation in Fatigue Severity Scale 7. Central activation failure (R = 0.416; 95% confidence interval = -1.618; P = 0.003) accounted for 17.3% (R(2)) of the variation in perceived effort score. Thus chronic stroke survivors with high fatigue exhibit high motor thresholds and those who perceive high effort have low excitability of inputs that drive motor cortex output. We suggest that low excitability of both corticospinal output and its facilitatory synaptic inputs from cortical and sub-cortical sites contribute to high levels of fatigue after stroke.
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Affiliation(s)
| | - Ella V Clark
- Sobell Department of Motor Neuroscience, Institute of Neurology, UCL, London, UK
| | - Isobel F Turner
- Sobell Department of Motor Neuroscience, Institute of Neurology, UCL, London, UK
| | - John C Rothwell
- Sobell Department of Motor Neuroscience, Institute of Neurology, UCL, London, UK
| | - Nick S Ward
- Sobell Department of Motor Neuroscience, Institute of Neurology, UCL, London, UK
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Nisiyama M, Ribeiro-do-Valle LE. Relative performance of the two hands in simple and choice reaction time tasks. ACTA ACUST UNITED AC 2013; 47:80-9. [PMID: 24345871 PMCID: PMC3932976 DOI: 10.1590/1414-431x20132932] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Accepted: 08/28/2013] [Indexed: 12/04/2022]
Abstract
There is evidence that the left hemisphere is more competent for motor control than
the right hemisphere. This study investigated whether this hemispheric asymmetry is
expressed in the latency/duration of sequential responses performed by the left
and/or right hands. Thirty-two right-handed young adults (16 males, 16 females; 18-25
years old) were tested in a simple or choice reaction time task. They responded to a
left and/or right visual target by moving their left and/or right middle fingers
between two keys on each side of the midline. Right hand reaction time did not differ
from left hand reaction time. Submovement times were longer for the right hand than
the left hand when the response was bilateral. Pause times were shorter for the right
hand than the left hand, both when the responses were unilateral or bilateral.
Reaction time results indicate that the putatively more efficient response
preparation by the left hemisphere motor mechanisms is not expressed behaviorally.
Submovement time and pause time results indicate that the putatively more efficient
response execution by the left hemisphere motor mechanisms is expressed behaviorally.
In the case of the submovements, the less efficient motor control of the left hand
would be compensated by a more intense attention to this hand.
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Affiliation(s)
- M Nisiyama
- Universidade de São Paulo, Instituto de Ciências Biomédicas, Departamento de Fisiologia e Biofísica, São PauloSP, Brasil, Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil
| | - L E Ribeiro-do-Valle
- Universidade de São Paulo, Instituto de Ciências Biomédicas, Departamento de Fisiologia e Biofísica, São PauloSP, Brasil, Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil
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Differentiation of motor cortical representation of hand muscles by navigated mapping of optimal TMS current directions in healthy subjects. J Clin Neurophysiol 2013; 30:390-5. [PMID: 23912579 DOI: 10.1097/wnp.0b013e31829dda6b] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
The precision of navigated transcranial magnetic stimulation (TMS) to map the human primary motor cortex may be effected by the direction of TMS-induced current in the brain as determined by the orientation of the stimulation coil. In this study, the authors investigated the effect of current directionality on motor output mapping using navigated brain stimulation. The goal of this study was to determine the optimal coil orientation (and, thus, induced brain current) to activate hand musculature representations relative to each subject's unique neuroanatomical landmarks. The authors studied motor output maps for the first dorsal interosseous, abductor pollicis brevis, and abductor digiti minimi muscles in 10 normal volunteers. Monopolar current pulses were delivered through a figure-of-eight-shaped TMS coil, and motor evoked potentials were recorded using electromyography. At each targeted brain region, the authors systematically rotated the TMS coil to determine the direction of induced current in the brain for induction of the largest motor evoked potentials. These optimal current directions were expressed as an angle relative to each subject's central sulcus. Consistency of the optimal current direction was assessed by repeating the entire mapping procedure on two different occasions across subjects. The authors demonstrate that systematic optimization of current direction as guided by MRI-based neuronavigation improves the resolution of cortical output motor mapping with TMS.
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45
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Laterality of quiet standing in old and young. Exp Brain Res 2013; 231:383-96. [DOI: 10.1007/s00221-013-3696-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Accepted: 08/31/2013] [Indexed: 10/26/2022]
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Tombini M, Pellegrino G, Pasqualetti P, Assenza G, Benvenga A, Fabrizio E, Rossini PM. Mobile Phone Emissions Modulate Brain Excitability in Patients with Focal Epilepsy. Brain Stimul 2013; 6:448-54. [DOI: 10.1016/j.brs.2012.07.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2012] [Revised: 06/16/2012] [Accepted: 07/14/2012] [Indexed: 11/28/2022] Open
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Ngomo S, Mercier C, Roy JS. Cortical mapping of the infraspinatus muscle in healthy individuals. BMC Neurosci 2013; 14:52. [PMID: 23617624 PMCID: PMC3652754 DOI: 10.1186/1471-2202-14-52] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Accepted: 04/20/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND While cortical representations of intrinsic hand muscles have been extensively studied in healthy individuals, little is known about the representation of proximal upper limb muscles. Improving our understanding of normal shoulder function is important, given that shoulder musculoskeletal disorders affect approximately 20% of the population and are suspected to involve changes in central motor representations. The purpose of the study is to describe the motor representation (motor evoked potentials (MEP) amplitude at the hotspot, map area, normalized map volume and center of gravity) of the infraspinatus muscle in healthy individuals, and to explore the potential influence of hand dominance on this representation (i.e. symmetry of the excitability and of the location of motor map between sides), as well as the effect of age and gender on motor excitability. RESULTS Fifteen healthy participants took part in this study. No significant asymmetry between sides was observed for motor excitability (p = 0.14), map area (p = 0.73) and normalized map volume (p = 0.34). Moreover, no side x intensity interaction was found (p = 0.54), indicating similar stimulus response properties. No difference between sides was found in the location of infraspinatus motor representation, either in the mediolateral or anteroposterior axis (p > 0.10). Neither age nor gender influenced aMT (p > 0.58) or MEP size (p > 0.61). CONCLUSIONS As the cortical representation of infraspinatus muscles was found to be symmetric between sides, both in terms of excitability and location, comparisons between the intact and affected side could be performed in clinical studies, regardless of whether the dominant or non-dominant side is affected. The next step will be to characterize corticospinal excitability and map parameters in populations with shoulder disorders.
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Affiliation(s)
- Suzy Ngomo
- Department of Rehabilitation, Faculty of Medicine, Laval University, Quebec City, QC, G1R 1P5, Canada
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48
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Bernard JA, Seidler RD. Hand dominance and age have interactive effects on motor cortical representations. PLoS One 2012; 7:e45443. [PMID: 23049800 PMCID: PMC3458089 DOI: 10.1371/journal.pone.0045443] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Accepted: 08/22/2012] [Indexed: 01/24/2023] Open
Abstract
Older adults exhibit more bilateral motor cortical activity during unimanual task performance than young adults. Interestingly, a similar pattern is seen in young adults with reduced hand dominance. However, older adults report stronger hand dominance than young adults, making it unclear how handedness is manifested in the aging motor cortex. Here, we investigated age differences in the relationships between handedness, motor cortical organization, and interhemispheric communication speed. We hypothesized that relationships between these variables would differ for young and older adults, consistent with our recent proposal of an age-related shift in interhemispheric interactions. We mapped motor cortical representations of the right and left first dorsal interosseous muscles using transcranial magnetic stimulation (TMS) in young and older adults recruited to represent a broad range of the handedness spectrum. We also measured interhemispheric communication speed and bimanual coordination. We observed that more strongly handed older adults exhibited more ipsilateral motor activity in response to TMS; this effect was not present in young adults. Furthermore, we found opposing relationships between interhemispheric communication speed and bimanual performance in the two age groups. Thus, handedness manifests itself differently in the motor cortices of young and older adults and has interactive effects with age.
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Affiliation(s)
- Jessica A Bernard
- Department of Psychology, University of Michigan, Ann Arbor, Michigan, USA.
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49
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An age-related change in the ipsilateral silent period of a small hand muscle. Clin Neurophysiol 2012; 124:346-53. [PMID: 22883478 DOI: 10.1016/j.clinph.2012.07.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Revised: 06/27/2012] [Accepted: 07/11/2012] [Indexed: 11/21/2022]
Abstract
OBJECTIVE To establish the presence or absence of an age effect on the ipsilateral silent period (iSP) for the abductor pollicis brevis (APB) muscle in healthy subjects. METHODS Twenty young adults (10 men, 10 women; age range: 20-40) and 20 older adults (10 men, 10 women; age range: 50-70) were matched by age (+30 years), gender and height (±5 cm). All were right-handed. We investigated the iSP for the APB by applying transcranial magnetic stimulation (TMS) and recording surface electromyograms. The contralateral motor-evoked potential (MEP) onset latency, the iSP onset and end latency (iSPOL and iSPEL) were measured and the iSP duration (iSPD) and transcallosal conduction time (TCT) were calculated. We evaluated the correlation between age and iSP, the latter's intra- and intersession reproducibility and potential influencing factors. RESULTS Mean iSPOL, iSPEL and TCT values were significantly greater in older adults (both men and women) than in young adults. Intra- and intersession reproducibility was good. The mean left-side iSPEL and iSPD were longer than the right-side mean values in young adults but not in older adults. In both age groups, women displayed shorter latencies than men. CONCLUSIONS There is a strong effect of age on iSP parameters. SIGNIFICANCE Our iSP results may evidence a decrease in transcallosal excitability with age, rather than slowing of the transcallosal interneuron conduction velocity.
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Johnson KA, Baig M, Ramsey D, Lisanby SH, Avery D, McDonald WM, Li X, Bernhardt ER, Haynor DR, Holtzheimer PE, Sackeim HA, George MS, Nahas Z. Prefrontal rTMS for treating depression: location and intensity results from the OPT-TMS multi-site clinical trial. Brain Stimul 2012; 6:108-17. [PMID: 22465743 DOI: 10.1016/j.brs.2012.02.003] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2011] [Revised: 02/15/2012] [Accepted: 02/17/2012] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Motor cortex localization and motor threshold determination often guide Transcranial Magnetic Stimulation (TMS) placement and intensity settings for non-motor brain stimulation. However, anatomic variability results in variability of placement and effective intensity. OBJECTIVE Post-study analysis of the OPT-TMS Study reviewed both the final positioning and the effective intensity of stimulation (accounting for relative prefrontal scalp-cortex distances). METHODS We acquired MRI scans of 185 patients in a multi-site trial of left prefrontal TMS for depression. Scans had marked motor sites (localized with TMS) and marked prefrontal sites (5 cm anterior of motor cortex by the "5 cm rule"). Based on a visual determination made before the first treatment, TMS therapy occurred either at the 5 cm location or was adjusted 1 cm forward. Stimulation intensity was 120% of resting motor threshold. RESULTS The "5 cm rule" would have placed stimulation in premotor cortex for 9% of patients, which was reduced to 4% with adjustments. We did not find a statistically significant effect of positioning on remission, but no patients with premotor stimulation achieved remission (0/7). Effective stimulation ranged from 93 to 156% of motor threshold, and no seizures were induced across this range. Patients experienced remission with effective stimulation intensity ranging from 93 to 146% of motor threshold, and we did not find a significant effect of effective intensity on remission. CONCLUSIONS Our data indicates that individualized positioning methods are useful to reduce variability in placement. Stimulation at 120% of motor threshold, unadjusted for scalp-cortex distances, appears safe for a broad range of patients.
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