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Assessment of Effective Connectivity and Plasticity With Dual-Coil Transcranial Magnetic Stimulation. Brain Stimul 2016; 9:347-355. [DOI: 10.1016/j.brs.2016.02.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 12/14/2015] [Accepted: 02/16/2016] [Indexed: 12/30/2022] Open
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202
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Ruiz-Veguilla M, Martín-Rodríguez JF, Palomar FJ, Porcacchia P, Álvarez de Toledo P, Perona-Garcelán S, Rodríguez-Testal JF, Huertas-Fernández I, Mir P. Trait- and state-dependent cortical inhibitory deficits in bipolar disorder. Bipolar Disord 2016; 18:261-71. [PMID: 27004755 DOI: 10.1111/bdi.12382] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 02/08/2016] [Indexed: 01/22/2023]
Abstract
OBJECTIVES Euthymic patients with bipolar disorder (BD) have deficits in cortical inhibition. However, whether cortical inhibitory deficits are trait- or state-dependent impairments is not yet known and their relationship with psychiatric symptoms is not yet understood. In the present study, we examined trait- and state-dependent cortical inhibitory deficits and evaluated the potential clinical significance of these deficits. METHODS Nineteen patients with bipolar I disorder were evaluated using the paired-pulse transcranial stimulation protocol, which assessed cortical inhibition during an acute manic episode. Cortical inhibition measures were compared with those obtained in 28 demographically matched healthy controls. A follow-up assessment was performed in 15 of these patients three months later, when there was remission from their mood and psychotic symptoms. The association between cortical inhibitory measures and severity of psychiatric symptoms was also studied. RESULTS During mania, patients showed decreased short-interval intracortical and transcallosal inhibition, as well as a normal cortical silent period and long-interval cortical inhibition. These findings were the same during euthymia. Symptoms associated with motor hyperactivity were correlated negatively with the degree of cortical inhibition. These correlations were not significant when a Bonferroni correction was applied. CONCLUSIONS The present longitudinal study showed cortical inhibitory deficits in patients with BD, and supports the hypothesis that cortical inhibitory deficits in BD are trait dependent. Further research is necessary to confirm the clinical significance of these deficits.
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Affiliation(s)
- Miguel Ruiz-Veguilla
- Grupo Neurodesarrollo y Psicosis, Instituto de Biomedicina de Sevilla (IBIS), Hospital Universitario Virgen del Rocio/CSIC/Universidad de Sevilla/UGC Salud Mental HVR, Seville, Spain
| | - Juan Francisco Martín-Rodríguez
- Unidad de Trastornos del Movimiento, Servicio de Neurología y Neurofisiología Clínica, Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Seville, Spain
| | - Francisco J Palomar
- Unidad de Trastornos del Movimiento, Servicio de Neurología y Neurofisiología Clínica, Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Seville, Spain
| | - Paolo Porcacchia
- Unidad de Trastornos del Movimiento, Servicio de Neurología y Neurofisiología Clínica, Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Seville, Spain
| | - Paloma Álvarez de Toledo
- Unidad de Trastornos del Movimiento, Servicio de Neurología y Neurofisiología Clínica, Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Seville, Spain
| | - Salvador Perona-Garcelán
- Grupo Neurodesarrollo y Psicosis, Instituto de Biomedicina de Sevilla (IBIS), Hospital Universitario Virgen del Rocio/CSIC/Universidad de Sevilla/UGC Salud Mental HVR, Seville, Spain
| | - Juan Francisco Rodríguez-Testal
- Grupo Neurodesarrollo y Psicosis, Instituto de Biomedicina de Sevilla (IBIS), Hospital Universitario Virgen del Rocio/CSIC/Universidad de Sevilla/UGC Salud Mental HVR, Seville, Spain.,Departamento de Personalidad, Evaluación y Tratamientos Psicológicos, Facultad de Psicología, Universidad de Sevilla, Seville, Spain
| | - Ismael Huertas-Fernández
- Unidad de Trastornos del Movimiento, Servicio de Neurología y Neurofisiología Clínica, Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Seville, Spain
| | - Pablo Mir
- Unidad de Trastornos del Movimiento, Servicio de Neurología y Neurofisiología Clínica, Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Seville, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Seville, Spain
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203
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Shirota Y, Sommer M, Paulus W. Strength-Duration Relationship in Paired-pulse Transcranial Magnetic Stimulation (TMS) and Its Implications for Repetitive TMS. Brain Stimul 2016; 9:755-761. [PMID: 27234142 DOI: 10.1016/j.brs.2016.04.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 04/25/2016] [Accepted: 04/27/2016] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Paired-pulse protocols have played a pivotal role in neuroscience research using transcranial magnetic stimulation (TMS). Stimulus parameters have been optimized over the years. More recently, pulse width (PW) has been introduced to this field as a new parameter, which may further fine-tune paired-pulse protocols. The relationship between the PW and effectiveness of a stimulus is known as the "strength-duration relationship". OBJECTIVE To test the "strength-duration relationship", so as to improve paired-pulse TMS protocols, and to apply the results to develop new repetitive TMS (rTMS) methods. METHODS Four protocols were investigated separately: short-interval intracortical inhibition (SICI), intracortical facilitation (ICF), short-interval intracortical facilitation (SICF) and long-interval intracortical inhibition (LICI). First, various stimulus parameters were tested to identify those yielding the largest facilitation or inhibition of the motor evoked potential (MEP) in each participant. Using these parameters, paired-pulse stimulations were repeated every five seconds for 30 minutes (repetitive paired-pulse stimulation, rPPS). The after-effects of rPPS were measured using MEP amplitude as an index of motor-cortical excitability. RESULTS Altogether, the effect of changing PW was similar to that of changing the stimulus intensity in the conventional settings. The best parameters were different for each participant. When these parameters were used, rPPS based on either SICF or ICF induced an increase in MEP amplitude. CONCLUSIONS PW was introduced as a new parameter in paired-pulse TMS. Modulation of PW influenced the results of paired-pulse protocols. rPPS using facilitatory protocols can be a good candidate to induce enhancement of motor-cortical excitability.
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Affiliation(s)
- Yuichiro Shirota
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Robert-Koch Straße 40, Göttingen 37075, Germany.
| | - Martin Sommer
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Robert-Koch Straße 40, Göttingen 37075, Germany
| | - Walter Paulus
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Robert-Koch Straße 40, Göttingen 37075, Germany
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204
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Säisänen L, Julkunen P, Kemppainen S, Danner N, Immonen A, Mervaala E, Määttä S, Muraja-Murro A, Könönen M. Locating and Outlining the Cortical Motor Representation Areas of Facial Muscles With Navigated Transcranial Magnetic Stimulation. Neurosurgery 2016; 77:394-405; discussion 405. [PMID: 26035404 DOI: 10.1227/neu.0000000000000798] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Navigated transcranial magnetic stimulation (nTMS) has become established as an accurate noninvasive technique for mapping the functional motor cortex for the representation areas of upper and lower limb muscles but not yet for facial musculature. OBJECTIVE To characterize the applicability and clinical impact of using nTMS to map cortical motor areas of facial muscles in healthy volunteers and neurosurgical tumor patients. METHODS Eight healthy volunteers and 12 patients with tumor were studied. The motor threshold (MT) was determined for the abductor pollicis brevis and mentalis muscles. The lateral part of the motor cortex was mapped with suprathreshold stimulation intensity, and motor evoked potentials were recorded from several facial muscles. The patient protocol was modified according to the clinical indication. RESULTS In all healthy subjects, motor evoked potentials were elicited in the mentalis (mean latency, 13.4 milliseconds) and orbicularis oris (mean latency, 12.6 milliseconds) muscles. At 110% of MT of the mentalis, the motor evoked potentials of facial muscles were elicited mainly in the precentral gyrus but also from one gyrus anterior and posterior to it. The cortical areas applicable for mapping were limited by an artifact attributable to direct peripheral nerve stimulation. The mapping protocol was successful in 10 of 12 tumor patients at locating the representation area of the lower facial muscles. The MT of the facial muscles was significantly higher than that of the abductor pollicis brevis. CONCLUSION nTMS is an applicable and clinically beneficial noninvasive method to preoperatively map the cortical representation areas of the facial muscles in the lower part of the face. Instead of using the MT of the abductor pollicis brevis, the stimulus intensity during mapping should be proportioned to the MT of a facial muscle.
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Affiliation(s)
- Laura Säisänen
- *Institute of Clinical Medicine, Faculty of Health Sciences and §Department of Applied Physics, University of Eastern Finland, Kuopio, Finland; ‡Departments of Clinical Neurophysiology, #Neurosurgery, and **Clinical Radiology, Kuopio University Hospital, Kuopio, Finland; ¶Department of Clinical Neurophysiology, NordLab Kajaani and ‖Kainuu Social and Health Care Joint Authority, Kainuu Central Hospital, Kajaani, Finland
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205
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Wischnewski M, Kowalski GM, Rink F, Belagaje SR, Haut MW, Hobbs G, Buetefisch CM. Demand on skillfulness modulates interhemispheric inhibition of motor cortices. J Neurophysiol 2016; 115:2803-13. [PMID: 26961108 DOI: 10.1152/jn.01076.2015] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Accepted: 03/08/2016] [Indexed: 11/22/2022] Open
Abstract
The role of primary motor cortex (M1) in the control of hand movements is still unclear. Functional magnetic resonance imaging (fMRI) studies of unimanual performance reported a relationship between level of precision of a motor task and additional ipsilateral M1 (iM1) activation. In the present study, we determined whether the demand on accuracy of a movement influences the magnitude of the inhibitory effect between primary motor cortices (IHI). We used transcranial magnetic stimulation (TMS) to measure active IHI (aIHI) of the iM1 on the contralateral M1 (cM1) in the premovement period of a left-hand motor task. Ten healthy participants manipulated a joystick to point to targets of two different sizes. For aIHI, the conditioning stimulus (CS) was applied to iM1, and the test stimulus (TS) to cM1, with an interstimulus interval of 10 ms. The amount of the inhibitory effect of the CS on the motor-evoked potential (MEP) of the subsequent TS was expressed as percentage of the mean MEP amplitude evoked by the single TS. Across different time points of aIHI measurements in the premovement period, there was a significant effect for target size on aIHI. Preparing to point to small targets was associated with weaker aIHI compared with pointing to large targets. The present findings suggest that, during the premovement period, aIHI from iM1 on cM1 is modulated by the demand on accuracy of the motor task. This is consistent with task fMRI findings showing bilateral M1 activation during high-precision movements but only unilateral M1 activity during low-precision movements.
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Affiliation(s)
| | | | | | - Samir R Belagaje
- Department of Neurology and Department of Rehabilitation Medicine, Emory University, Atlanta, Georgia
| | | | - Gerald Hobbs
- Department of Biostatistics, West Virginia University, Morgantown, West Virginia
| | - Cathrin M Buetefisch
- Department of Neurology and Department of Rehabilitation Medicine, Emory University, Atlanta, Georgia;
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206
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Hermsen A, Haag A, Duddek C, Balkenhol K, Bugiel H, Bauer S, Mylius V, Menzler K, Rosenow F. Test–retest reliability of single and paired pulse transcranial magnetic stimulation parameters in healthy subjects. J Neurol Sci 2016; 362:209-16. [DOI: 10.1016/j.jns.2016.01.039] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Revised: 12/28/2015] [Accepted: 01/20/2016] [Indexed: 10/22/2022]
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207
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Melnikova EA. [Analysis of the cerebral mechanisms underlying rehabilitation of the patients after stroke]. VOPROSY KURORTOLOGII, FIZIOTERAPII, I LECHEBNOĬ FIZICHESKOĬ KULTURY 2016; 92:4-10. [PMID: 26841522 DOI: 10.17116/kurort201564-10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The authors present the results of the comprehensive analysis of the principal cerebral mechanisms involved in the processes of rehabilitation of the patients after stroke based on the review of the literature concerning this issue. The data obtained in the course of original investigations including 203 patients who had undergone stroke confirm and refine the currently available information pertinent to the problem in question. First and foremost, they demonstrate the influence of the demographic, neurophysiological, and clinical factors as well as neuroimaging and ultrasound studies on the parameters of the evoked potentials in the brain of the stroke-affected patients. In addition, they provide a deeper insight into the role of short-term memory in the realization of the motor response. The probable macro- and microstructural, functional, neurochemical, and pathophysiological mechanisms contributing to the rehabilitation of the patients who had undergone stroke are considered with reference to their relationships. Special emphasis is laid on the methods for regulation of these mechanisms.
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Affiliation(s)
- E A Melnikova
- State autonomous healthcare facility 'Moscow Research and Practical Centre for Medical Rehabilitation, Restorative and Sports Medicine', Moscow Health Department, Moscow, Russian Federation, 105120
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208
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Tremblay C, Monetta L, Langlois M, Schneider C. Intermittent Theta-Burst Stimulation of the Right Dorsolateral Prefrontal Cortex to Promote Metaphor Comprehension in Parkinson Disease: A Case Study. Arch Phys Med Rehabil 2016; 97:74-83. [DOI: 10.1016/j.apmr.2015.09.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 09/06/2015] [Accepted: 09/10/2015] [Indexed: 10/23/2022]
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209
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Massé-Alarie H, Beaulieu LD, Preuss R, Schneider C. Corticomotor control of lumbar multifidus muscles is impaired in chronic low back pain: concurrent evidence from ultrasound imaging and double-pulse transcranial magnetic stimulation. Exp Brain Res 2015; 234:1033-45. [PMID: 26708518 DOI: 10.1007/s00221-015-4528-x] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Accepted: 12/10/2015] [Indexed: 12/14/2022]
Abstract
Chronic low back pain (CLBP) is often associated with impaired control of deep trunk muscles and reorganization of the primary motor areas (M1). Precisely, functional changes of the lumbar multifidus muscles (MF) involved in spine stability may be of special interest in rehabilitation. Therefore, we tested MF corticomotor control using double transcranial magnetic stimulation (TMS) paradigms for the first time in this muscle and examined its link with MF volitional activation. Eleven individuals with lateralized CLBP and 13 pain-free participants were recruited. Ultrasound imaging enabled measurement of MF volitional isometric contraction in prone lying. TMS of MF M1 area was used to test hemispheric excitability and mechanisms in relation to motor programming, i.e., active motor threshold (AMT), amplitude of motor-evoked potentials and short-interval intracortical inhibition (SICI) and facilitation (SICF). In CLBP, SICI level was lower in the left hemisphere and MF volitional contraction was not related to AMT (M1 excitability), conversely to what was observed in the pain-free group. No other between-group difference was detected. These original findings support a plasticity of cortical maps controlling paravertebral muscles and likely including a different motor strategy for the control of MF. Changes of M1 function may thus underlie impaired motor control of lumbopelvic spine and pain persistence in CLBP.
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Affiliation(s)
- Hugo Massé-Alarie
- Laboratory of Clinical Neuroscience and Neurostimulation, Neuroscience Division of the Centre de Recherche du CHU de Québec, RC-9800, 2705 Blvd. Laurier, Quebec City, QC, G1V 4G2, Canada.,Constance Lethbridge Rehabilitation Center Research Site of the CRIR, Montreal, QC, Canada
| | - Louis-David Beaulieu
- Laboratory of Clinical Neuroscience and Neurostimulation, Neuroscience Division of the Centre de Recherche du CHU de Québec, RC-9800, 2705 Blvd. Laurier, Quebec City, QC, G1V 4G2, Canada
| | - Richard Preuss
- Constance Lethbridge Rehabilitation Center Research Site of the CRIR, Montreal, QC, Canada.,School of Physical and Occupational Therapy, McGill University, Montreal, QC, Canada
| | - Cyril Schneider
- Laboratory of Clinical Neuroscience and Neurostimulation, Neuroscience Division of the Centre de Recherche du CHU de Québec, RC-9800, 2705 Blvd. Laurier, Quebec City, QC, G1V 4G2, Canada. .,Department of Rehabilitation, Faculty of Medicine, Université Laval, Québec City, QC, Canada.
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210
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Taubert M, Villringer A, Lehmann N. Endurance Exercise as an "Endogenous" Neuro-enhancement Strategy to Facilitate Motor Learning. Front Hum Neurosci 2015; 9:692. [PMID: 26834602 PMCID: PMC4714627 DOI: 10.3389/fnhum.2015.00692] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2015] [Accepted: 12/07/2015] [Indexed: 11/13/2022] Open
Abstract
Endurance exercise improves cardiovascular and musculoskeletal function and may also increase the information processing capacities of the brain. Animal and human research from the past decade demonstrated widespread exercise effects on brain structure and function at the systems-, cellular-, and molecular level of brain organization. These neurobiological mechanisms may explain the well-established positive influence of exercise on performance in various behavioral domains but also its contribution to improved skill learning and neuroplasticity. With respect to the latter, only few empirical and theoretical studies are available to date. The aim of this review is (i) to summarize the existing neurobiological and behavioral evidence arguing for endurance exercise-induced improvements in motor learning and (ii) to develop hypotheses about the mechanistic link between exercise and improved learning. We identify major knowledge gaps that need to be addressed by future research projects to advance our understanding of how exercise should be organized to optimize motor learning.
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Affiliation(s)
- Marco Taubert
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig Germany
| | - Arno Villringer
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, LeipzigGermany; Clinic for Cognitive Neurology, University Hospital Leipzig, LeipzigGermany
| | - Nico Lehmann
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig Germany
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211
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Repetition suppression in transcranial magnetic stimulation-induced motor-evoked potentials is modulated by cortical inhibition. Neuroscience 2015; 310:504-11. [DOI: 10.1016/j.neuroscience.2015.09.056] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Revised: 08/27/2015] [Accepted: 09/21/2015] [Indexed: 01/03/2023]
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212
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Hanlon CA, DeVries W, Dowdle LT, West JA, Siekman B, Li X, George MS. A comprehensive study of sensorimotor cortex excitability in chronic cocaine users: Integrating TMS and functional MRI data. Drug Alcohol Depend 2015; 157:28-35. [PMID: 26541870 PMCID: PMC4899825 DOI: 10.1016/j.drugalcdep.2015.07.1196] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Revised: 06/23/2015] [Accepted: 07/09/2015] [Indexed: 10/23/2022]
Abstract
BACKGROUND Disruptions in motor control are often overlooked features of chronic cocaine users. During a simple sensorimotor integration task, for example, cocaine users activate a larger area of cortex than controls but have lower functional connectivity between the cortex and dorsal striatum, which is further correlated with poor performance. The purpose of this study was to determine whether abnormal cortical excitability in cocaine users was related to disrupted inhibitory or excitatory mechanisms, as measured by transcranial magnetic stimulation (TMS). METHODS A battery of TMS measures were acquired from 87 individuals (50 cocaine dependent, 37 controls). Functional MRI data were acquired from a subset of 28 individuals who performed a block-design finger tapping task. RESULTS TMS measures revealed that cocaine users had significantly higher resting motor thresholds and higher intracortical cortical facilitation (ICF) than controls. There was no between-group difference in either measure of cortical inhibition. Task-evoked BOLD signal in the motor cortex was significantly correlated with ICF in the cocaine users. There was no significant difference in brain-skull distance between groups. CONCLUSION These data demonstrated that cocaine users have disrupted cortical facilitation (as measured with TMS), which is related to elevated BOLD signal. Cortical inhibition, however, is largely intact. Given the relationship between ICF and glutamatergic agents, this may be a potentially fruitful and treatable target in addiction. Finally, among controls the distance from the scalp to the cortex was correlated with the motor threshold which may be a useful parameter to integrate into therapeutic TMS protocols in the future.
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Affiliation(s)
- Colleen A. Hanlon
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States,Corresponding author at: Departments of Psychiatry and Neurosciences, Medical University of South Carolina, Charleston, SC, United States. (C.A. Hanlon)
| | - William DeVries
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States
| | - Logan T. Dowdle
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States,Ralph H.Johnson VA Medical Center, Charleston, SC, United States
| | - Julia A. West
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States,Ralph H.Johnson VA Medical Center, Charleston, SC, United States
| | - Bradley Siekman
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States,Ralph H.Johnson VA Medical Center, Charleston, SC, United States
| | - Xingbao Li
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States
| | - Mark S. George
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States,Ralph H.Johnson VA Medical Center, Charleston, SC, United States
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213
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Papegaaij S, Taube W, van Keeken HG, Otten E, Baudry S, Hortobágyi T. Postural challenge affects motor cortical activity in young and old adults. Exp Gerontol 2015; 73:78-85. [PMID: 26615878 DOI: 10.1016/j.exger.2015.11.015] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Revised: 10/27/2015] [Accepted: 11/23/2015] [Indexed: 11/18/2022]
Abstract
When humans voluntarily activate a muscle, intracortical inhibition decreases. Such a decrease also occurs in the presence of a postural challenge and more so with increasing age. Here, we examined age-related changes in motor cortical activity during postural and non-postural contractions with varying levels of postural challenge. Fourteen young (age 22) and twelve old adults (age 70) performed three conditions: (1) voluntary contraction of the soleus muscle in sitting and (2) leaning forward while standing with and (3) without being supported. Subthreshold transcranial magnetic stimulation was applied to the soleus motor area suppressing ongoing EMG, as an index of motor cortical activity. The area of EMG suppression was ~60% smaller (p<0.05) in unsupported vs. supported leaning and sitting, with no difference between these latter two conditions (p>0.05). Even though in absolute terms young compared with old adults leaned farther (p=0.018), there was no age effect or an age by condition interaction in EMG suppression. Leaning closer to the maximum without support correlated with less EMG suppression (rho=-0.44, p=0.034). We conclude that the critical factor in modulating motor cortical activity was postural challenge and not contraction aim or posture. Age did not affect the motor control strategy as quantified by the modulation of motor cortical activity, but the modulation appeared at a lower task difficulty with increasing age.
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Affiliation(s)
- Selma Papegaaij
- University of Groningen, University Medical Center Groningen, Center for Human Movement Sciences, Antonius Deusinglaan 1, 9713AV, Groningen, The Netherlands.
| | - Wolfgang Taube
- University of Fribourg, Department of Medicine, Ch. du Musée 8, CH-1700, Fribourg, Switzerland
| | - Helco G van Keeken
- University of Groningen, University Medical Center Groningen, Center for Human Movement Sciences, Antonius Deusinglaan 1, 9713AV, Groningen, The Netherlands
| | - Egbert Otten
- University of Groningen, University Medical Center Groningen, Center for Human Movement Sciences, Antonius Deusinglaan 1, 9713AV, Groningen, The Netherlands
| | - Stéphane Baudry
- Université Libre de Bruxelles, Faculty for Motor Sciences, Laboratory of Applied Biology, CP 640, Route de Lennik 808, 1070 Brussels, Belgium
| | - Tibor Hortobágyi
- University of Groningen, University Medical Center Groningen, Center for Human Movement Sciences, Antonius Deusinglaan 1, 9713AV, Groningen, The Netherlands; Department of Sport, Exercise and Rehabilitation, Northumbria University, Newcastle-upon-Tyne NE1 8ST, United Kingdom
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214
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Frontoparietal white matter integrity predicts haptic performance in chronic stroke. NEUROIMAGE-CLINICAL 2015; 10:129-39. [PMID: 26759788 PMCID: PMC4683424 DOI: 10.1016/j.nicl.2015.11.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 11/06/2015] [Accepted: 11/11/2015] [Indexed: 11/21/2022]
Abstract
Frontoparietal white matter supports information transfer between brain areas involved in complex haptic tasks such as somatosensory discrimination. The purpose of this study was to gain an understanding of the relationship between microstructural integrity of frontoparietal network white matter and haptic performance in persons with chronic stroke and to compare frontoparietal network integrity in participants with stroke and age matched control participants. Nineteen individuals with stroke and 16 controls participated. Haptic performance was quantified using the Hand Active Sensation Test (HASTe), an 18-item match-to-sample test of weight and texture discrimination. Three tesla MRI was used to obtain diffusion-weighted and high-resolution anatomical images of the whole brain. Probabilistic tractography was used to define 10 frontoparietal tracts total; Four intrahemispheric tracts measured bilaterally 1) thalamus to primary somatosensory cortex (T–S1), 2) thalamus to primary motor cortex (T–M1), 3) primary to secondary somatosensory cortex (S1 to SII) and 4) primary somatosensory cortex to middle frontal gyrus (S1 to MFG) and, 2 interhemispheric tracts; S1–S1 and precuneus interhemispheric. A control tract outside the network, the cuneus interhemispheric tract, was also examined. The diffusion metrics fractional anisotropy (FA), mean diffusivity (MD), axial (AD) and radial diffusivity (RD) were quantified for each tract. Diminished FA and elevated MD values are associated with poorer white matter integrity in chronic stroke. Nine of 10 tracts quantified in the frontoparietal network had diminished structural integrity poststroke compared to the controls. The precuneus interhemispheric tract was not significantly different between groups. Principle component analysis across all frontoparietal white matter tract MD values indicated a single factor explained 47% and 57% of the variance in tract mean diffusivity in stroke and control groups respectively. Age strongly correlated with the shared variance across tracts in the control, but not in the poststroke participants. A moderate to good relationship was found between ipsilesional T–M1 MD and affected hand HASTe score (r = − 0.62, p = 0.006) and less affected hand HASTe score (r = − 0.53, p = 0.022). Regression analysis revealed approximately 90% of the variance in affected hand HASTe score was predicted by the white matter integrity in the frontoparietal network (as indexed by MD) in poststroke participants while 87% of the variance in HASTe score was predicted in control participants. This study demonstrates the importance of frontoparietal white matter in mediating haptic performance and specifically identifies that T–M1 and precuneus interhemispheric tracts may be appropriate targets for piloting rehabilitation interventions, such as noninvasive brain stimulation, when the goal is to improve poststroke haptic performance. Poststroke participants had a wide range of haptic performance, the majority were impaired. A good relationship was found between ipsilesional Thal–M1 integrity and poststroke haptics. Around 90% of haptic performance was predicted by frontoparietal white matter integrity. Precuneus interhemispheric tract integrity was a strong predictor of haptic performance. Diminished integrity across the frontoparietal network suggests a general stroke-related factor.
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215
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Rice DA, Graven-Nielsen T, Lewis GN, McNair PJ, Dalbeth N. The effects of experimental knee pain on lower limb corticospinal and motor cortex excitability. Arthritis Res Ther 2015; 17:204. [PMID: 26264180 PMCID: PMC4534119 DOI: 10.1186/s13075-015-0724-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Accepted: 07/23/2015] [Indexed: 01/25/2023] Open
Abstract
Introduction Notable weakness of the quadriceps muscles is typically observed as a consequence of knee joint arthritis, knee surgery and knee injury. This is partly due to ongoing neural inhibition that prevents the central nervous system from fully activating the quadriceps, a process known as arthrogenic muscle inhibition (AMI). To investigate the mechanisms underlying AMI, this study explored the effects of experimental knee pain on lower limb corticospinal and motor cortex excitability. Methods Twenty-four healthy volunteers participated in this study. In experiment 1, experimental knee pain was induced by the injection of hypertonic saline into the infrapatellar fat pad (n = 18). In experiment 2, isotonic saline was injected into the fat pad as a non-painful control (n = 8). Pain intensity was measured on a 10-cm electronic visual analogue scale. Transcranial magnetic stimulation and electromyography were used to measure lower limb motor-evoked potential amplitude and short-interval intracortical inhibition before and after the injection. Results The peak VAS score following hypertonic saline (5.0 ± 0.5 cm) was higher than after isotonic saline (p <0.001). Compared with baseline, there was a significant increase in vastus lateralis (p = 0.02) and vastus medialis motor-evoked potential amplitude (p = 0.02) during experimental knee pain that was not apparent during the control condition. Biceps femoris and tibialis anterior motor-evoked potential amplitude did not change following injection (all p >0.05). There was no change in short-interval intracortical inhibition measured from vastus lateralis following injection (both p >0.05). Conclusions Quadriceps corticospinal excitability increases during experimental knee pain, providing no evidence for a supraspinal contribution to quadriceps AMI.
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Affiliation(s)
- David Andrew Rice
- Health and Rehabilitation Research Institute, Auckland University of Technology, 55 Wellesley Street East, Auckland, 1010, New Zealand. .,Waitemata Pain Services, Department of Anaesthesiology and Perioperative Medicine, Waitemata District Health Board, Shakespeare Road, Auckland, 0620, New Zealand.
| | - Thomas Graven-Nielsen
- Center for Sensory-Motor Interaction (SMI), Department of Health Science and Technology, Faculty of Medicine, Aalborg University, Fredrik Bajers Vej 5, 9100, Aalborg, Denmark.
| | - Gwyn Nancy Lewis
- Health and Rehabilitation Research Institute, Auckland University of Technology, 55 Wellesley Street East, Auckland, 1010, New Zealand.
| | - Peter John McNair
- Health and Rehabilitation Research Institute, Auckland University of Technology, 55 Wellesley Street East, Auckland, 1010, New Zealand.
| | - Nicola Dalbeth
- Department of Medicine, University of Auckland, 2 Park Road, Auckland, 1023, New Zealand.
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216
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Introduction to Nonconvulsive Brain Stimulation: Focus on Transcranial Magnetic Stimulation. Brain Stimul 2015. [DOI: 10.1002/9781118568323.ch9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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217
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Welniarz Q, Dusart I, Gallea C, Roze E. One hand clapping: lateralization of motor control. Front Neuroanat 2015; 9:75. [PMID: 26082690 PMCID: PMC4451425 DOI: 10.3389/fnana.2015.00075] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 05/17/2015] [Indexed: 12/20/2022] Open
Abstract
Lateralization of motor control refers to the ability to produce pure unilateral or asymmetric movements. It is required for a variety of coordinated activities, including skilled bimanual tasks and locomotion. Here we discuss the neuroanatomical substrates and pathophysiological underpinnings of lateralized motor outputs. Significant breakthroughs have been made in the past few years by studying the two known conditions characterized by the inability to properly produce unilateral or asymmetric movements, namely human patients with congenital “mirror movements” and model rodents with a “hopping gait”. Whereas mirror movements are associated with altered interhemispheric connectivity and abnormal corticospinal projections, abnormal spinal cord interneurons trajectory is responsible for the “hopping gait”. Proper commissural axon guidance is a critical requirement for these mechanisms. Interestingly, the analysis of these two conditions reveals that the production of asymmetric movements involves similar anatomical and functional requirements but in two different structures: (i) lateralized activation of the brain or spinal cord through contralateral silencing by cross-midline inhibition; and (ii) unilateral transmission of this activation, resulting in lateralized motor output.
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Affiliation(s)
- Quentin Welniarz
- Neuroscience Paris Seine, CNRS UMR8246, Inserm U1130, Sorbonne Universités, UPMC UM119 Paris, France ; Inserm U1127, CNRS UMR 7225, Sorbonne Universités, UPMC UMR S1127, Institut du Cerveau et de la Moelle épinière, ICM Paris, France
| | - Isabelle Dusart
- Neuroscience Paris Seine, CNRS UMR8246, Inserm U1130, Sorbonne Universités, UPMC UM119 Paris, France
| | - Cécile Gallea
- Inserm U1127, CNRS UMR 7225, Sorbonne Universités, UPMC UMR S1127, Institut du Cerveau et de la Moelle épinière, ICM Paris, France
| | - Emmanuel Roze
- Inserm U1127, CNRS UMR 7225, Sorbonne Universités, UPMC UMR S1127, Institut du Cerveau et de la Moelle épinière, ICM Paris, France ; Département des Maladies du Système Nerveux, AP-HP, Hôpital Pitié Salpêtrière Paris, France
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218
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Lefebvre G, Tremblay S, Théoret H. Probing the effects of mild traumatic brain injury with transcranial magnetic stimulation of the primary motor cortex. Brain Inj 2015; 29:1032-43. [DOI: 10.3109/02699052.2015.1028447] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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219
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Rio E, Kidgell D, Purdam C, Gaida J, Moseley GL, Pearce AJ, Cook J. Isometric exercise induces analgesia and reduces inhibition in patellar tendinopathy. Br J Sports Med 2015; 49:1277-83. [PMID: 25979840 DOI: 10.1136/bjsports-2014-094386] [Citation(s) in RCA: 163] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/20/2015] [Indexed: 12/28/2022]
Abstract
BACKGROUND Few interventions reduce patellar tendinopathy (PT) pain in the short term. Eccentric exercises are painful and have limited effectiveness during the competitive season. Isometric and isotonic muscle contractions may have an immediate effect on PT pain. METHODS This single-blinded, randomised cross-over study compared immediate and 45 min effects following a bout of isometric and isotonic muscle contractions. Outcome measures were PT pain during the single-leg decline squat (SLDS, 0-10), quadriceps strength on maximal voluntary isometric contraction (MVIC), and measures of corticospinal excitability and inhibition. Data were analysed using a split-plot in time-repeated measures analysis of variance (ANOVA). RESULTS 6 volleyball players with PT participated. Condition effects were detected with greater pain relief immediately from isometric contractions: isometric contractions reduced SLDS (mean±SD) from 7.0±2.04 to 0.17±0.41, and isotonic contractions reduced SLDS (mean±SD) from 6.33±2.80 to 3.75±3.28 (p<0.001). Isometric contractions released cortical inhibition (ratio mean±SD) from 27.53%±8.30 to 54.95%±5.47, but isotonic contractions had no significant effect on inhibition (pre 30.26±3.89, post 31.92±4.67; p=0.004). Condition by time analysis showed pain reduction was sustained at 45 min postisometric but not isotonic condition (p<0.001). The mean reduction in pain scores postisometric was 6.8/10 compared with 2.6/10 postisotonic. MVIC increased significantly following the isometric condition by 18.7±7.8%, and was significantly higher than baseline (p<0.001) and isotonic condition (p<0.001), and at 45 min (p<0.001). CONCLUSIONS A single resistance training bout of isometric contractions reduced tendon pain immediately for at least 45 min postintervention and increased MVIC. The reduction in pain was paralleled by a reduction in cortical inhibition, providing insight into potential mechanisms. Isometric contractions can be completed without pain for people with PT. The clinical implications are that isometric muscle contractions may be used to reduce pain in people with PT without a reduction in muscle strength.
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Affiliation(s)
- Ebonie Rio
- Department of Physiotherapy, School of Primary Health Care, Monash University, Melbourne, Victoria, Australia
| | - Dawson Kidgell
- Department of Rehabilitation, Nutrition and Sport, School of Allied Health, La Trobe University, Melbourne, Victoria, Australia
| | - Craig Purdam
- Department of Physical Therapies, Australian Institute of Sport, Bruce, Australian Capital Territory, Australia
| | - Jamie Gaida
- Department of Physiotherapy, School of Primary Health Care, Monash University, Melbourne, Victoria, Australia University of Canberra, Canberra, Australian Capital Territory, Australia
| | - G Lorimer Moseley
- Sansom Institute for Health Research, University of South Australia & Pain Adelaide, Adelaide, South Australia, Australia
| | - Alan J Pearce
- Cognitive Neuroscience Unit, Deakin University, Burwood, Victoria, Australia
| | - Jill Cook
- Department of Physiotherapy, School of Primary Health Care, Monash University, Melbourne, Victoria, Australia
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Karabanov A, Ziemann U, Hamada M, George MS, Quartarone A, Classen J, Massimini M, Rothwell J, Siebner HR. Consensus Paper: Probing Homeostatic Plasticity of Human Cortex With Non-invasive Transcranial Brain Stimulation. Brain Stimul 2015; 8:442-54. [DOI: 10.1016/j.brs.2015.01.404] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 01/03/2015] [Accepted: 01/13/2015] [Indexed: 01/03/2023] Open
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Increase in Short-Interval Intracortical Facilitation of the Motor Cortex after Low-Frequency Repetitive Magnetic Stimulation of the Unaffected Hemisphere in the Subacute Phase after Stroke. Neural Plast 2015; 2015:407320. [PMID: 26060584 PMCID: PMC4427769 DOI: 10.1155/2015/407320] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Revised: 04/06/2015] [Accepted: 04/07/2015] [Indexed: 11/17/2022] Open
Abstract
Low-frequency repetitive transcranial magnetic stimulation of the unaffected hemisphere (UH-LF-rTMS) in patients with stroke can decrease interhemispheric inhibition from the unaffected to the affected hemisphere and improve hand dexterity and strength of the paretic hand. The objective of this proof-of-principle study was to explore, for the first time, effects of UH-LF-rTMS as add-on therapy to motor rehabilitation on short-term intracortical inhibition (SICI) and intracortical facilitation (ICF) of the motor cortex of the unaffected hemisphere (M1UH) in patients with ischemic stroke. Eighteen patients were randomized to receive, immediately before rehabilitation treatment, either active or sham UH-LF-rTMS, during two weeks. Resting motor threshold (rMT), SICI, and ICF were measured in M1UH before the first session and after the last session of treatment. There was a significant increase in ICF in the active group compared to the sham group after treatment, and there was no significant differences in changes in rMT or SICI. ICF is a measure of intracortical synaptic excitability, with a relative contribution of spinal mechanisms. ICF is typically upregulated by glutamatergic agonists and downregulated by gabaergic antagonists. The observed increase in ICF in the active group, in this hypothesis-generating study, may be related to M1UH reorganization induced by UH-LF-rTMS.
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222
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Corticobasal degeneration: clinical characteristics and multidisciplinary therapeutic approach in 26 patients. Neurol Sci 2015; 36:1651-7. [PMID: 25917399 DOI: 10.1007/s10072-015-2226-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 04/17/2015] [Indexed: 01/28/2023]
Abstract
Corticobasal syndrome (CBS) is a sporadic tauopathy that manifests by a various combination of motor and cognitive deficits, which makes its diagnosis challenging. Treatment of CBS is symptomatic and based on evidence from other similar disorders due to the lack of studies on CBS. The aim of the study was to investigate low-frequency repetitive transcranial magnetic stimulation (rTMS) as a therapeutic tool in CBS. Twenty-six patients with clinically evident CBS according to Cambridge criteria were followed for 12-18 months while receiving low-frequency rTMS combined with pharmacological, rehabilitation treatment and botulinum toxin injection. The majority of patients are manifested with akinetic-rigid syndrome and cognitive dysfunction. There was improvement of the UPDRS and quality of life after 3 months of therapeutic interventions (P < 0.001 and <0.05, respectively). No significant deterioration in cognitive functions was detected over the study period. There was a significant reduction of caregiver burden after 3 months of interventions (P < 0.01); this improvement was maintained up to 18 months. Cognitive dysfunction is a frequent manifestation of CBS. CBS patients can benefit from multidisciplinary therapeutic approach employing low-frequency rTMS.
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223
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Clark BC, Taylor JL, Hong SL, Law TD, Russ DW. Weaker Seniors Exhibit Motor Cortex Hypoexcitability and Impairments in Voluntary Activation. J Gerontol A Biol Sci Med Sci 2015; 70:1112-9. [PMID: 25834195 DOI: 10.1093/gerona/glv030] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Accepted: 03/02/2015] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Weakness predisposes seniors to a fourfold increase in functional limitations. The potential for age-related degradation in nervous system function to contribute to weakness and physical disability has garnered much interest of late. In this study, we tested the hypothesis that weaker seniors have impairments in voluntary (neural) activation and increased indices of GABAergic inhibition of the motor cortex, assessed using transcranial magnetic stimulation. METHODS Young adults (N = 46; 21.2±0.5 years) and seniors (N = 42; 70.7±0.9 years) had their wrist flexion strength quantified along with voluntary activation capacity (by comparing voluntary and electrically evoked forces). Single-pulse transcranial magnetic stimulation was used to measure motor-evoked potential amplitude and silent period duration during isometric contractions at 15% and 30% of maximum strength. Paired-pulse transcranial magnetic stimulation was used to measure intracortical facilitation and short-interval and long-interval intracortical inhibition. The primary analysis compared seniors to young adults. The secondary analysis compared stronger seniors (top two tertiles) to weaker seniors (bottom tertile) based on strength relative to body weight. RESULTS The most novel findings were that weaker seniors exhibited: (i) a 20% deficit in voluntary activation; (ii) ~20% smaller motor-evoked potentials during the 30% contraction task; and (iii) nearly twofold higher levels of long-interval intracortical inhibition under resting conditions. CONCLUSIONS These findings indicate that weaker seniors exhibit significant impairments in voluntary activation, and that this impairment may be mechanistically associated with increased GABAergic inhibition of the motor cortex.
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Affiliation(s)
| | - Janet L Taylor
- Neuroscience Research Australia and the University of New South Wales, Randwick, Australia
| | | | - Timothy D Law
- Ohio Musculoskeletal and Neurological Institute (OMNI) at Ohio University, Athens. Department of Family Medicine at Ohio University, Athens
| | - David W Russ
- Ohio Musculoskeletal and Neurological Institute (OMNI) at Ohio University, Athens. School of Rehabilitation and Communication Sciences at Ohio University, Athens
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Helm F, Marinovic W, Krüger B, Munzert J, Riek S. Corticospinal excitability during imagined and observed dynamic force production tasks: Effortfulness matters. Neuroscience 2015; 290:398-405. [DOI: 10.1016/j.neuroscience.2015.01.050] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 01/20/2015] [Accepted: 01/22/2015] [Indexed: 11/24/2022]
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225
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Seeing fearful body language rapidly freezes the observer's motor cortex. Cortex 2015; 65:232-45. [DOI: 10.1016/j.cortex.2015.01.014] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2014] [Revised: 11/21/2014] [Accepted: 01/20/2015] [Indexed: 12/12/2022]
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226
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Leonard CT, Danna-dos-Santos A, Peters C, Moore M. Corticomotor excitability changes during mirrored or asynergistic wrist movements. Behav Brain Res 2015; 281:199-207. [DOI: 10.1016/j.bbr.2014.12.026] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 12/10/2014] [Accepted: 12/11/2014] [Indexed: 10/24/2022]
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227
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Matsuura R, Ogata T. Effects of fatiguing unilateral plantar flexions on corticospinal and transcallosal inhibition in the primary motor hand area. J Physiol Anthropol 2015; 34:4. [PMID: 25857538 PMCID: PMC4340114 DOI: 10.1186/s40101-015-0042-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 01/16/2015] [Indexed: 12/02/2022] Open
Abstract
Background Corticospinal excitability of the primary motor cortex (M1) representing the hand muscle is depressed by bilateral lower limb muscle fatigue. The effects of fatiguing unilateral lower limb contraction on corticospinal excitability and transcallosal inhibition in the M1 hand areas remain unclear. The purpose of this study was to determine the effects of fatiguing unilateral plantar flexions on corticospinal excitability in the M1 hand areas and transcallosal inhibition originated from the M1 hand area contralateral to the fatigued ankle. Methods Ten healthy volunteers (26.2 ± 3.8 years) participated in the study. Using transcranial magnetic stimulation, we examined motor evoked potentials (MEPs) and interhemispheric inhibition (IHI) recorded from resting first dorsal interosseous (FDI) muscles before, immediately after, and 10 min after fatiguing unilateral lower limb muscle contraction, which was consisted of 40 unilateral maximal isometric plantar flexions intermittently with a 2-s contraction followed by 1 s of rest. Results We demonstrated no significant changes in MEPs in the FDI muscle ipsilateral to the fatigued ankle and decrease in IHI from the M1 hand area contralateral to the fatigued ankle to the ipsilateral M1 hand area after the fatiguing contraction. MEPs in the FDI muscle contralateral to the fatigued ankle were increased after the fatiguing contraction. Conclusions These results suggest that fatiguing unilateral lower limb muscle contraction differently influences corticospinal excitability of the contralateral M1 hand area and IHI from the contralateral M1 hand area to the ipsilateral M1 hand area. Although fatiguing unilateral lower limb muscle contraction increases corticospinal excitability of the ipsilateral M1 hand area, the increased corticospinal excitability is not associated with the decreased IHI.
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228
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Beaulieu LD, Massé-Alarie H, Brouwer B, Schneider C. Noninvasive neurostimulation in chronic stroke: a double-blind randomized sham-controlled testing of clinical and corticomotor effects. Top Stroke Rehabil 2015; 22:8-17. [PMID: 25776116 DOI: 10.1179/1074935714z.0000000032] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND Repetitive peripheral magnetic stimulation (RPMS) is a painless and noninvasive method to produce afferents via the depolarization of the peripheral nervous system. A few studies tested RPMS after-effects on cerebral plasticity and motor recovery in stroke individuals, but evidences remain limited. OBJECTIVES This study aimed to explore whether RPMS could mediate improvements in corticomotor and clinical outcomes associated with ankle impairments in chronic stroke. METHODS Eighteen subjects with chronic stroke were randomly allocated to RPMS or sham group and compared to 14 healthy subjects. Stimulation was applied over the paretic tibialis anterior (TA). Ankle impairments on the paretic side and ipsilesional TA cortical motor representation were tested clinically and by transcranial magnetic stimulation (TMS), respectively. RESULTS In the RPMS group, ankle dorsiflexion mobility and maximal isometric strength increased and resistance to plantar flexor stretch decreased. The magnitude of change seemed to be related to cortical and corticospinal integrity. Sham stimulation yielded no effect. Changes in TMS outcome and their relationships with clinical improvements were limited. CONCLUSIONS RPMS improved ankle impairments in chronic stroke likely by a dynamic influence of sensory inputs on synaptic plasticity. The neurophysiological mechanisms potentially underlying the clinical effects are unclear. More studies are warranted to test the spinal and hemispheric changes responsible for the clinical improvements with emphasis on circuits spared by the lesion.
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Schabrun SM, Christensen SW, Mrachacz-Kersting N, Graven-Nielsen T. Motor Cortex Reorganization and Impaired Function in the Transition to Sustained Muscle Pain. Cereb Cortex 2015; 26:1878-90. [PMID: 25609242 DOI: 10.1093/cercor/bhu319] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Primary motor cortical (M1) adaptation has not been investigated in the transition to sustained muscle pain. Daily injection of nerve growth factor (NGF) induces hyperalgesia reminiscent of musculoskeletal pain and provides a novel model to study M1 in response to progressively developing muscle soreness. Twelve healthy individuals were injected with NGF into right extensor carpi radialis brevis (ECRB) on Days 0 and 2 and with hypertonic saline on Day 4. Quantitative sensory and motor testing and assessment of M1 organization and function using transcranial magnetic stimulation were performed prior to injection on Days 0, 2, and 4 and again on Day 14. Pain and disability increased at Day 2 and increased further at Day 4. Reorganization of M1 was evident at Day 4 and was characterized by increased map excitability. These changes were accompanied by reduced intracortical inhibition and increased intracortical facilitation. Interhemispheric inhibition was reduced from the "affected" to the "unaffected" hemisphere on Day 4, and this was associated with increased pressure sensitivity in left ECRB. These data provide the first evidence of M1 adaptation in the transition to sustained muscle pain and have relevance for the development of therapies that seek to target M1 in musculoskeletal pain.
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Affiliation(s)
- S M Schabrun
- School of Science and Health, University of Western Sydney, Penrith, NSW 2751, Australia
| | - S W Christensen
- Laboratory for Musculoskeletal Pain and Motor Control, Center for Sensory-Motor Interaction (SMI), Department of Health Science and Technology, Faculty of Medicine, Aalborg University, Aalborg, Denmark
| | - N Mrachacz-Kersting
- Laboratory for Musculoskeletal Pain and Motor Control, Center for Sensory-Motor Interaction (SMI), Department of Health Science and Technology, Faculty of Medicine, Aalborg University, Aalborg, Denmark
| | - T Graven-Nielsen
- Laboratory for Musculoskeletal Pain and Motor Control, Center for Sensory-Motor Interaction (SMI), Department of Health Science and Technology, Faculty of Medicine, Aalborg University, Aalborg, Denmark
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230
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The uses and interpretations of the motor-evoked potential for understanding behaviour. Exp Brain Res 2015; 233:679-89. [DOI: 10.1007/s00221-014-4183-7] [Citation(s) in RCA: 202] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 12/09/2014] [Indexed: 12/21/2022]
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231
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Ziemann U, Reis J, Schwenkreis P, Rosanova M, Strafella A, Badawy R, Müller-Dahlhaus F. TMS and drugs revisited 2014. Clin Neurophysiol 2014; 126:1847-68. [PMID: 25534482 DOI: 10.1016/j.clinph.2014.08.028] [Citation(s) in RCA: 450] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2014] [Revised: 08/03/2014] [Accepted: 08/24/2014] [Indexed: 12/18/2022]
Abstract
The combination of pharmacology and transcranial magnetic stimulation to study the effects of drugs on TMS-evoked EMG responses (pharmaco-TMS-EMG) has considerably improved our understanding of the effects of TMS on the human brain. Ten years have elapsed since an influential review on this topic has been published in this journal (Ziemann, 2004). Since then, several major developments have taken place: TMS has been combined with EEG to measure TMS evoked responses directly from brain activity rather than by motor evoked potentials in a muscle, and pharmacological characterization of the TMS-evoked EEG potentials, although still in its infancy, has started (pharmaco-TMS-EEG). Furthermore, the knowledge from pharmaco-TMS-EMG that has been primarily obtained in healthy subjects is now applied to clinical settings, for instance, to monitor or even predict clinical drug responses in neurological or psychiatric patients. Finally, pharmaco-TMS-EMG has been applied to understand the effects of CNS active drugs on non-invasive brain stimulation induced long-term potentiation-like and long-term depression-like plasticity. This is a new field that may help to develop rationales of pharmacological treatment for enhancement of recovery and re-learning after CNS lesions. This up-dated review will highlight important knowledge and recent advances in the contribution of pharmaco-TMS-EMG and pharmaco-TMS-EEG to our understanding of normal and dysfunctional excitability, connectivity and plasticity of the human brain.
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Affiliation(s)
- Ulf Ziemann
- Department of Neurology & Stroke, and Hertie Institute for Clinical Brain Research, Eberhard-Karls-University Tübingen, Tübingen, Germany.
| | - Janine Reis
- Department of Neurology, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Peter Schwenkreis
- Department of Neurology, BG-University Hospital Bergmannsheil Bochum, Bochum, Germany
| | - Mario Rosanova
- Department of Biomedical and Clinical Sciences "Luigi Sacco", University of Milan, Milan, Italy; Fondazione Europea di Ricerca Biomedica, FERB Onlus, Milan, Italy
| | - Antonio Strafella
- Morton and Gloria Shulman Movement Disorder Unit & E.J. Safra Parkinson Disease Program, Toronto Western Hospital, UHN, University of Toronto, Ontario, Canada; Research Imaging Centre, Centre for Addiction and Mental Health, University of Toronto, Ontario, Canada
| | - Radwa Badawy
- Department of Neurology, Saint Vincent's Hospital, Fitzroy, The University of Melbourne, Parkville, Victoria, Australia; Department of Medicine, The University of Melbourne, Parkville, Victoria, Australia
| | - Florian Müller-Dahlhaus
- Department of Neurology & Stroke, and Hertie Institute for Clinical Brain Research, Eberhard-Karls-University Tübingen, Tübingen, Germany
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232
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Farias da Guarda SN, Conforto AB. Effects of somatosensory stimulation on corticomotor excitability in patients with unilateral cerebellar infarcts and healthy subjects - preliminary results. CEREBELLUM & ATAXIAS 2014; 1:16. [PMID: 26331040 PMCID: PMC4552362 DOI: 10.1186/s40673-014-0016-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Accepted: 09/05/2014] [Indexed: 02/04/2023]
Abstract
Background In healthy humans, somatosensory stimulation in the form of 2 h-repetitive peripheral afferent nerve stimulation (SS) increases excitability of the contralateral motor cortex. In this preliminary study, we explored effects of SS on excitability to transcranial magnetic stimulation (TMS) in patients with unilateral cerebellar infarcts and age-matched controls. Methods Ten patients with infarcts in one cerebellar hemisphere and six age-matched controls participated in the study. Each subject participated in one session of active, and one session of sham SS delivered to the median nerve ipsilateral to the cerebellar infarct in patients, and to the homologous nerve in controls. Before and after each session, the following TMS measures were performed: resting motor threshold (rMT), motor evoked potentials (MEPs), short-interval intracortical inhibition (SICI) and short-interval intracortical facilitation (SICF). Amplitudes of motor evoked potentials were normalized to amplitudes of supramaximal M responses (MEP/M ratios). Results In the control group, there was a significant increase in rMT, and a significant increase in MEP/M ratios after active, but not after sham SS. There were no significant differences in rMT or MEP/M ratios in the group of patients after active or sham SS. There were no significant differences in SICI or SICF after active or sham SS in either group. Conclusion Consistent with results reported in rodents, these preliminary findings suggest for the first time in humans, that normal cerebellar activity is required so that SS can modulate excitability of the sensorimotor cortex.
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Affiliation(s)
- Suzete Nascimento Farias da Guarda
- Hospital das Clínicas/São Paulo University, São Paulo, Brazil ; Hospital São Rafael, Salvador, Brazil ; Rua Waldemar Falcão n 1547 ap 1201 Horto Florestal 40.295-010, Salvador, Bahia Brazil
| | - Adriana Bastos Conforto
- Hospital das Clínicas/São Paulo University, São Paulo, Brazil ; Instituto Israelita de Ensino e Pesquisa Albert Einstein, São Paulo, Brazil
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233
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Stagg CJ, Bachtiar V, Johansen-Berg H. What are we measuring with GABA Magnetic Resonance Spectroscopy? Commun Integr Biol 2014. [DOI: 10.4161/cib.16213] [Citation(s) in RCA: 120] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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234
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Hoegl T, Bender S, Buchmann J, Kratz O, Moll GH, Heinrich H. [Transcranial magnetic stimulation (TMS), inhibition processes and attention deficit/hyperactivity disorder (ADHD) - an overview]. ZEITSCHRIFT FUR KINDER-UND JUGENDPSYCHIATRIE UND PSYCHOTHERAPIE 2014; 42:415-28; quiz 428-9. [PMID: 25335520 DOI: 10.1024/1422-4917/a000320] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Motor system excitability can be tested by transcranial magnetic stimulation CFMS). In this article, an overview of recent methodological developments and research findings related to attention deficit/hyperactivity disorder (ADHD) is provided. Different TMS parameters that reflect the function of interneurons in the motor cortex may represent neurophysiological markers of inhibition in ADHD, particularly the so-called intracortical inhibition. In children with a high level of hyperactivity and impulsivity, intracortical inhibition was comparably low at rest as shortly before the execution of a movement. TMS-evoked potentials can also be measured in the EEG so that investigating processes of excitability is not restricted to motor areas in future studies. The effects of methylphenidate on motor system excitability may be interpreted in the sense of a 'fine-tuning' with these mainly dopaminergic effects also depending on genetic parameters (DAT1 transporter). A differentiated view on the organization of motor control can be achieved by a combined analysis of TMS parameters and event-related potentials. Applying this bimodal approach, strong evidence for a deviant implementation of motor control in children with ADHD and probably compensatory mechanisms (with involvement of the prefrontal cortex) was obtained. These findings, which contribute to a better understanding of hyperactivity/impulsivity, inhibitory processes and motor control in ADHD as well as the mechanisms of medication, underline the relevance of TMS as a neurophysiological method in ADHD research.
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Affiliation(s)
- Thomas Hoegl
- Kinder- u. Jugendabteilung für Psychische Gesundheit, Universitätsklinikum Erlangen
| | - Stephan Bender
- Klinik für Psychiatrie, Psychosomatik und Psychotherapie des Kindes- und Jugendalters, J. W. Goethe Universitätsklinikum, Frankfurt am Main
| | - Johannes Buchmann
- Klinik für Psychiatrie, Neurologie, Psychosomatik und Psychotherapie im Kindes- und Jugendalter, Zentrum Nervenheilkunde, Universität Rostock
| | - Oliver Kratz
- Kinder- u. Jugendabteilung für Psychische Gesundheit, Universitätsklinikum Erlangen
| | - Gunther H Moll
- Kinder- u. Jugendabteilung für Psychische Gesundheit, Universitätsklinikum Erlangen
| | - Hartmut Heinrich
- Kinder- u. Jugendabteilung für Psychische Gesundheit, Universitätsklinikum Erlangen Heckscher-Klinikum, München
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235
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Clark BC, Mahato NK, Nakazawa M, Law TD, Thomas JS. The power of the mind: the cortex as a critical determinant of muscle strength/weakness. J Neurophysiol 2014; 112:3219-26. [PMID: 25274345 DOI: 10.1152/jn.00386.2014] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
We tested the hypothesis that the nervous system, and the cortex in particular, is a critical determinant of muscle strength/weakness and that a high level of corticospinal inhibition is an important neurophysiological factor regulating force generation. A group of healthy individuals underwent 4 wk of wrist-hand immobilization to induce weakness. Another group also underwent 4 wk of immobilization, but they also performed mental imagery of strong muscle contractions 5 days/wk. Mental imagery has been shown to activate several cortical areas that are involved with actual motor behaviors, including premotor and M1 regions. A control group, who underwent no interventions, also participated in this study. Before, immediately after, and 1 wk following immobilization, we measured wrist flexor strength, voluntary activation (VA), and the cortical silent period (SP; a measure that reflect corticospinal inhibition quantified via transcranial magnetic stimulation). Immobilization decreased strength 45.1 ± 5.0%, impaired VA 23.2 ± 5.8%, and prolonged the SP 13.5 ± 2.6%. Mental imagery training, however, attenuated the loss of strength and VA by ∼50% (23.8 ± 5.6% and 12.9 ± 3.2% reductions, respectively) and eliminated prolongation of the SP (4.8 ± 2.8% reduction). Significant associations were observed between the changes in muscle strength and VA (r = 0.56) and SP (r = -0.39). These findings suggest neurological mechanisms, most likely at the cortical level, contribute significantly to disuse-induced weakness, and that regular activation of the cortical regions via imagery attenuates weakness and VA by maintaining normal levels of inhibition.
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Affiliation(s)
- Brian C Clark
- Ohio Musculoskeletal and Neurological Institute (OMNI), Ohio University, Athens, Ohio; Department of Biomedical Sciences, Ohio University, Athens, Ohio; Department of Geriatric Medicine, Ohio University, Athens, Ohio;
| | - Niladri K Mahato
- Ohio Musculoskeletal and Neurological Institute (OMNI), Ohio University, Athens, Ohio
| | - Masato Nakazawa
- Ohio Musculoskeletal and Neurological Institute (OMNI), Ohio University, Athens, Ohio; Office of Research, Ohio University, Athens, Ohio
| | - Timothy D Law
- Ohio Musculoskeletal and Neurological Institute (OMNI), Ohio University, Athens, Ohio; Department of Family Medicine, Ohio University, Athens, Ohio; and
| | - James S Thomas
- Ohio Musculoskeletal and Neurological Institute (OMNI), Ohio University, Athens, Ohio; Department of Biomedical Sciences, Ohio University, Athens, Ohio; School of Rehabilitation and Communication Sciences, Ohio University, Athens, Ohio
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236
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Liao DA, Kronemer SI, Yau JM, Desmond JE, Marvel CL. Motor system contributions to verbal and non-verbal working memory. Front Hum Neurosci 2014; 8:753. [PMID: 25309402 PMCID: PMC4173669 DOI: 10.3389/fnhum.2014.00753] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 09/07/2014] [Indexed: 11/28/2022] Open
Abstract
Working memory (WM) involves the ability to maintain and manipulate information held in mind. Neuroimaging studies have shown that secondary motor areas activate during WM for verbal content (e.g., words or letters), in the absence of primary motor area activation. This activation pattern may reflect an inner speech mechanism supporting online phonological rehearsal. Here, we examined the causal relationship between motor system activity and WM processing by using transcranial magnetic stimulation (TMS) to manipulate motor system activity during WM rehearsal. We tested WM performance for verbalizable (words and pseudowords) and non-verbalizable (Chinese characters) visual information. We predicted that disruption of motor circuits would specifically affect WM processing of verbalizable information. We found that TMS targeting motor cortex slowed response times (RTs) on verbal WM trials with high (pseudoword) vs. low (real word) phonological load. However, non-verbal WM trials were also significantly slowed with motor TMS. WM performance was unaffected by sham stimulation or TMS over visual cortex (VC). Self-reported use of motor strategy predicted the degree of motor stimulation disruption on WM performance. These results provide evidence of the motor system’s contributions to verbal and non-verbal WM processing. We speculate that the motor system supports WM by creating motor traces consistent with the type of information being rehearsed during maintenance.
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Affiliation(s)
- Diana A Liao
- Department of Neurology, Johns Hopkins University School of Medicine Baltimore, MD, USA ; Neuroscience Institute, Princeton University Princeton, NJ, USA
| | - Sharif I Kronemer
- Department of Neurology, Johns Hopkins University School of Medicine Baltimore, MD, USA
| | - Jeffrey M Yau
- Department of Neurology, Johns Hopkins University School of Medicine Baltimore, MD, USA ; Department of Neuroscience, Baylor College of Medicine Houston, TX, USA
| | - John E Desmond
- Department of Neurology, Johns Hopkins University School of Medicine Baltimore, MD, USA
| | - Cherie L Marvel
- Department of Neurology, Johns Hopkins University School of Medicine Baltimore, MD, USA ; Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine Baltimore, MD, USA
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237
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Arias P, Robles-García V, Corral-Bergantiños Y, Espinosa N, Mordillo-Mateos L, Grieve K, Oliviero A, Cudeiro J. Balancing the excitability of M1 circuitry during movement observation without overt replication. Front Behav Neurosci 2014; 8:316. [PMID: 25278854 PMCID: PMC4166319 DOI: 10.3389/fnbeh.2014.00316] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 08/27/2014] [Indexed: 11/29/2022] Open
Abstract
Although observation of a movement increases the excitability of the motor system of the observer, it does not induce a motor replica. What is the mechanism for replica suppression? We performed a series of experiments, involving a total of 66 healthy humans, to explore the excitability of different M1 circuits and the spinal cord during observation of simple movements. Several strategies were used. In the first and second experimental blocks, we used several delay times from movement onset to evaluate the time-course modulation of the cortico-spinal excitability (CSE), and its potential dependency on the duration of the movement observed; in order to do this single pulse transcranial magnetic stimulation (TMS) over M1 was used. In subsequent experiments, at selected delay times from movement-onset, we probed the excitability of the cortico-spinal circuits using three different approaches: (i) electric cervicomedullary stimulation (CMS), to test spinal excitability, (ii) paired-pulse TMS over M1, to evaluate the cortical inhibitory-excitatory balance (short intracortical inhibition (SICI) and intracortical facilitation (ICF)], and (iii) continuous theta-burst stimulation (cTBS), to modulate the excitability of M1 cortical circuits. We observed a stereotyped response in the modulation of CSE. At 500 ms after movement-onset the ICF was increased; although the most clear-cut effect was a decrease of CSE. The compensatory mechanism was not explained by changes in SICI, but by M1-intracortical circuits targeted by cTBS. Meanwhile, the spinal cord maintained the elevated level of excitability induced when expecting to observe movements, potentially useful to facilitate any required response to the movement observed.
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Affiliation(s)
- Pablo Arias
- Laboratory of Neuroscience and Motor Control (NEUROcom), Department of Medicine-INEF-Galicia and Institute of Biomedical Research of Coruña (INIBIC), University of A Coruña Spain
| | - Verónica Robles-García
- Laboratory of Neuroscience and Motor Control (NEUROcom), Department of Medicine-INEF-Galicia and Institute of Biomedical Research of Coruña (INIBIC), University of A Coruña Spain
| | - Yoanna Corral-Bergantiños
- Laboratory of Neuroscience and Motor Control (NEUROcom), Department of Medicine-INEF-Galicia and Institute of Biomedical Research of Coruña (INIBIC), University of A Coruña Spain
| | - Nelson Espinosa
- Laboratory of Neuroscience and Motor Control (NEUROcom), Department of Medicine-INEF-Galicia and Institute of Biomedical Research of Coruña (INIBIC), University of A Coruña Spain
| | - Laura Mordillo-Mateos
- FENNSI Group, Hospital Nacional de Parapléjicos, Servicio de Salud de Castilla-La Mancha Toledo, Spain
| | - Kenneth Grieve
- Faculty of Life Sciences, University of Manchester Manchester, UK
| | - Antonio Oliviero
- FENNSI Group, Hospital Nacional de Parapléjicos, Servicio de Salud de Castilla-La Mancha Toledo, Spain
| | - Javier Cudeiro
- Laboratory of Neuroscience and Motor Control (NEUROcom), Department of Medicine-INEF-Galicia and Institute of Biomedical Research of Coruña (INIBIC), University of A Coruña Spain
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238
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Brodie SM, Villamayor A, Borich MR, Boyd LA. Exploring the specific time course of interhemispheric inhibition between the human primary sensory cortices. J Neurophysiol 2014; 112:1470-6. [DOI: 10.1152/jn.00074.2014] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The neurophysiological mechanism of interhemispheric inhibition (IHI) between the human primary sensory cortices (S1s) is poorly understood. Here we used a paired median nerve somatosensory evoked potential protocol to observe S1-S1 IHI from the dominant to the nondominant hemisphere with electroencephalography. In 10 healthy, right-handed individuals, we compared mean peak-to-peak amplitudes of five somatosensory evoked potential components (P14/N20, N20/P25, P25/N30, N30/P40, and P40/N60) recorded over the right S1 after synchronous versus asynchronous stimulation of the right and left median nerves. Asynchronous conditioning + test stimuli (CS+TS) were delivered at interstimulus intervals of 15, 20, 25, 30, and 35 ms. We found that, in relation to synchronous stimulation, when a CS to the left S1 preceded a TS to the right S1 at the short intervals (15 and 20 ms) the amplitude of the cortical N20/P25 complex was significantly depressed, whereas at the longer intervals (25, 30, and 35 ms) significant inhibition was observed for the thalamocortical P14/N20 as well as the cortical N20/P25 components. We conclude that the magnitude of S1 IHI appears to depend on the temporal asynchrony of bilateral inputs and the specific timing is likely reflective of a direct transcallosal mechanism. Employing a method that enables direct S1 IHI to be reliably quantified may provide a novel tool to assess potential IHI imbalances in individuals with neurological damage, such as stroke.
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Affiliation(s)
- Sonia M. Brodie
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada; and
| | - Anica Villamayor
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada; and
| | - Michael R. Borich
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada; and
| | - Lara A. Boyd
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada; and
- Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada
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239
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Solopova I, Selionov V, Kazennikov O, Ivanenko Y. Effects of transcranial magnetic stimulation during voluntary and non-voluntary stepping movements in humans. Neurosci Lett 2014; 579:64-9. [DOI: 10.1016/j.neulet.2014.07.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Revised: 07/06/2014] [Accepted: 07/08/2014] [Indexed: 01/01/2023]
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240
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Deer TR, Krames E, Mekhail N, Pope J, Leong M, Stanton-Hicks M, Golovac S, Kapural L, Alo K, Anderson J, Foreman RD, Caraway D, Narouze S, Linderoth B, Buvanendran A, Feler C, Poree L, Lynch P, McJunkin T, Swing T, Staats P, Liem L, Williams K. The Appropriate Use of Neurostimulation: New and Evolving Neurostimulation Therapies and Applicable Treatment for Chronic Pain and Selected Disease States. Neuromodulation 2014; 17:599-615; discussion 615. [DOI: 10.1111/ner.12204] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Revised: 01/14/2014] [Accepted: 02/07/2014] [Indexed: 12/20/2022]
Affiliation(s)
| | | | - Nagy Mekhail
- University of Kentucky-Lexington; Lexington KY USA
| | - Jason Pope
- Center for Pain Relief; Charleston WV USA
| | | | | | | | - Leo Kapural
- Carolinas Pain Institute at Brookstown; Wake Forest Baptist Health; Winston-Salem NC USA
| | - Ken Alo
- The Methodist Hospital Research Institute; Houston TX USA
- Monterey Technical Institute; Monterey Mexico
| | | | - Robert D. Foreman
- University of Oklahoma Health Sciences Center, College of Medicine; Oklahoma City OK USA
| | - David Caraway
- Center for Pain Relief, Tri-State, LLC; Huntington WV USA
| | - Samer Narouze
- Anesthesiology and Pain Medicine, Neurological Surgery; Summa Western Reserve Hospital; Cuyahoga Falls OH USA
| | - Bengt Linderoth
- Functional Neurosurgery and Applied Neuroscience Research Unit, Karolinska Institute; Karolinska University Hospital; Stockholm Sweden
| | | | - Claudio Feler
- University of Tennessee; Memphis TN USA
- Valley View Hospital; Glenwood Springs CO USA
| | - Lawrence Poree
- University of California at San Francisco; San Francisco CA USA
- Pain Clinic of Monterey Bay; Aptos CA
| | - Paul Lynch
- Arizona Pain Specialists; Scottsdale AZ USA
| | | | - Ted Swing
- Arizona Pain Specialists; Scottsdale AZ USA
| | - Peter Staats
- Premier Pain Management Centers; Shrewsbury NJ USA
- Johns Hopkins University; Baltimore MD USA
| | - Liong Liem
- St. Antonius Hospital; Nieuwegein The Netherlands
| | - Kayode Williams
- Johns Hopkins School of Medicine and Carey Business School; Baltimore MD USA
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241
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Abstract
Current data suggest that transcranial magnetic stimulation (TMS) has the potential to be an effective and complimentary treatment modality for patients with chronic neuropathic pain syndromes. The success of TMS for pain relief depends on the parameters of the stimulation delivered, the location of neural target, and duration of treatment. TMS can be used to excite or inhibit underlying neural tissue that depends on long-term potentiation and long-term depression, respectively. Long-term randomized controlled studies are warranted to establish the efficacy of repetitive TMS in patients with various chronic pain syndromes.
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Affiliation(s)
- Nicole A Young
- Department of Neuroscience, Center of Neuromodulation, Wexner Medical Center, The Ohio State University, 480 Medical Center Drive, Columbus, OH 43210, USA
| | - Mayur Sharma
- Department of Neurosurgery, Center of Neuromodulation, Wexner Medical Center, The Ohio State University, 480 Medical Center Drive, Columbus, OH 43210, USA
| | - Milind Deogaonkar
- Department of Neurosurgery, Center of Neuromodulation, Wexner Medical Center, The Ohio State University, 480 Medical Center Drive, Columbus, OH 43210, USA.
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242
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Bachtiar V, Stagg CJ. The role of inhibition in human motor cortical plasticity. Neuroscience 2014; 278:93-104. [PMID: 25090923 DOI: 10.1016/j.neuroscience.2014.07.059] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 06/10/2014] [Accepted: 07/24/2014] [Indexed: 11/26/2022]
Abstract
Over recent years evidence from animal studies strongly suggests that a decrease in local inhibitory signaling is necessary for synaptic plasticity to occur. However, the role of GABAergic modulation in human motor plasticity is less well understood. Here, we summarize the techniques available to quantify GABA in humans, before reviewing the existing evidence for the role of inhibitory signaling in human motor plasticity. We discuss a number of important outstanding questions that remain before the role of GABAergic modulation in long-term plasticity in humans, such as that underpinning recovery after stroke, can be established.
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Affiliation(s)
- V Bachtiar
- Oxford Centre for Functional MRI of the Brain (FMRIB), Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - C J Stagg
- Oxford Centre for Functional MRI of the Brain (FMRIB), Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
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243
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Excitability of the motor cortex in de novo patients with celiac disease. PLoS One 2014. [PMID: 25062250 DOI: 10.1371/journal.pone.0102790.] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
INTRODUCTION Celiac disease (CD) may initially present as a neurological disorder or may be complicated by neurological changes. To date, neurophysiological studies aiming to an objective evaluation of the potential central nervous system involvement in CD are lacking. OBJECTIVE To assess the profile of cortical excitability to Transcranial Magnetic Stimulation (TMS) in a group of de novo CD patients. MATERIALS AND METHODS Twenty CD patients underwent a screening for cognitive and neuropsychiatric symptoms by means of the Mini Mental State Examination and the Structured Clinical Interview for DSM-IV Axis I Disorders, respectively. Instrumental exams, including electroencephalography and brain computed tomography, were also performed. Cortico-spinal excitability was assessed by means of single and paired-pulse TMS using the first dorsal interosseus muscle of the dominant hand. TMS measures consisted of resting motor threshold, motor evoked potentials, cortical silent period (CSP), intracortical inhibition (ICI) and facilitation (ICF). None of the CD was on gluten-free diet. A group of 20 age-matched healthy controls was used for comparisons. RESULTS CD showed a significantly shorter CSP (78.0 vs 125.0 ms, p<0.025), a reduced ICI (0.3 vs 0.2, p<0.045) and an enhanced ICF (1.1 vs 0.7, p<0.042) compared to controls. A dysthymic disorder was identified in five patients. The effect size between dysthymic and non-dysthymic CD patients indicated a low probability of interference with the CSP (Cohen's d -0.414), ICI (-0.278) and ICF (-0.292) measurements. CONCLUSION A pattern of cortical excitability characterized by "disinhibition" and "hyperfacilitation" was found in CD patients. Immune system dysregulation might play a central role in triggering changes of the motor cortex excitability.
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244
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Studer P, Kratz O, Gevensleben H, Rothenberger A, Moll GH, Hautzinger M, Heinrich H. Slow cortical potential and theta/beta neurofeedback training in adults: effects on attentional processes and motor system excitability. Front Hum Neurosci 2014; 8:555. [PMID: 25104932 PMCID: PMC4109432 DOI: 10.3389/fnhum.2014.00555] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2014] [Accepted: 07/08/2014] [Indexed: 11/13/2022] Open
Abstract
Neurofeedback (NF) is being successfully applied, among others, in children with attention deficit/hyperactivity disorder (ADHD) and as a peak performance training in healthy subjects. However, the neuronal mechanisms mediating a successful NF training have not yet been sufficiently uncovered for both theta/beta (T/B), and slow cortical potential (SCP) training, two protocols established in NF in ADHD. In the present, randomized, controlled investigation in adults without a clinical diagnosis (n = 59), the specificity of the effects of these two NF protocols on attentional processes and motor system excitability were to be examined, focusing on the underlying neuronal mechanisms. Neurofeedback training consisted of 10 double sessions, and self-regulation skills were analyzed. Pre- and post-training assessments encompassed performance and event-related potential measures during an attention task, and motor system excitability assessed by transcranial magnetic stimulation. Some NF protocol-specific effects have been obtained. However, due to the limited sample size medium effects did not reach the level of significance. Self-regulation abilities during negativity trials of the SCP training were associated with increased contingent negative variation amplitudes, indicating improved resource allocation during cognitive preparation. Theta/beta training was associated with increased response speed and decreased target-P3 amplitudes after successful theta/beta regulation suggested reduced attentional resources necessary for stimulus evaluation. Motor system excitability effects after theta/beta training paralleled the effects of methylphenidate. Overall, our results are limited by the non-sufficiently acquired self-regulation skills, but some specific effects between good and poor learners could be described. Future studies with larger sample sizes and sufficient acquisition of self-regulation skills are needed to further evaluate the protocol-specific effects on attention and motor system excitability reported.
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Affiliation(s)
- Petra Studer
- Department of Child and Adolescent Mental Health, University Hospital of Erlangen Erlangen, Germany
| | - Oliver Kratz
- Department of Child and Adolescent Mental Health, University Hospital of Erlangen Erlangen, Germany
| | - Holger Gevensleben
- Child and Adolescent Psychiatry, University Medical Center Göttingen Göttingen, Germany
| | - Aribert Rothenberger
- Child and Adolescent Psychiatry, University Medical Center Göttingen Göttingen, Germany
| | - Gunther H Moll
- Department of Child and Adolescent Mental Health, University Hospital of Erlangen Erlangen, Germany
| | - Martin Hautzinger
- Department of Clinical Psychology, Institute of Psychology, Eberhard Karls University Tübingen Tübingen, Germany
| | - Hartmut Heinrich
- Department of Child and Adolescent Mental Health, University Hospital of Erlangen Erlangen, Germany ; Heckscher-Klinikum, München Germany
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245
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Coxon JP, Peat NM, Byblow WD. Primary motor cortex disinhibition during motor skill learning. J Neurophysiol 2014; 112:156-64. [DOI: 10.1152/jn.00893.2013] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Motor learning requires practice over a period of time and depends on brain plasticity, yet even for relatively simple movements, there are multiple practice strategies that can be used for skill acquisition. We investigated the role of intracortical inhibition in the primary motor cortex (M1) during motor skill learning. Event-related transcranial magnetic stimulation (TMS) was used to assess corticomotor excitability and inhibition thought to involve synaptic and extrasynaptic γ-aminobutyric acid (GABA). Short intracortical inhibition (SICI) was assessed using 1- and 2.5-ms interstimulus intervals (ISIs). Participants learned a novel, sequential pinch-grip task on a computer in either a repetitive or interleaved practice structure. Both practice structures showed equivalent levels of motor performance at the end of acquisition and at retention 1 wk later. There was a novel task-related modulation of 1-ms SICI. Repetitive practice elicited a greater reduction of 1- and 2.5-ms SICI, i.e., disinhibition, between rest and task acquisition, compared with interleaved practice. These novel findings support the use of a repetitive practice structure for motor learning because the associated effects within M1 have relevance for motor rehabilitation.
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Affiliation(s)
- James P. Coxon
- Movement Neuroscience Laboratory, Department of Sport & Exercise Science, The University of Auckland, Auckland, New Zealand; and
- Centre for Brain Research, The University of Auckland, Auckland, New Zealand
| | - Nicola M. Peat
- Movement Neuroscience Laboratory, Department of Sport & Exercise Science, The University of Auckland, Auckland, New Zealand; and
| | - Winston D. Byblow
- Movement Neuroscience Laboratory, Department of Sport & Exercise Science, The University of Auckland, Auckland, New Zealand; and
- Centre for Brain Research, The University of Auckland, Auckland, New Zealand
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246
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Prichard G, Weiller C, Fritsch B, Reis J. Effects of Different Electrical Brain Stimulation Protocols on Subcomponents of Motor Skill Learning. Brain Stimul 2014; 7:532-40. [DOI: 10.1016/j.brs.2014.04.005] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Revised: 04/09/2014] [Accepted: 04/11/2014] [Indexed: 10/25/2022] Open
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247
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Therapeutic applications of repetitive transcranial magnetic stimulation (rTMS) in movement disorders: A review. Parkinsonism Relat Disord 2014; 20:695-707. [DOI: 10.1016/j.parkreldis.2014.03.018] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Revised: 03/10/2014] [Accepted: 03/18/2014] [Indexed: 11/19/2022]
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248
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Liew SL, Santarnecchi E, Buch ER, Cohen LG. Non-invasive brain stimulation in neurorehabilitation: local and distant effects for motor recovery. Front Hum Neurosci 2014; 8:378. [PMID: 25018714 PMCID: PMC4072967 DOI: 10.3389/fnhum.2014.00378] [Citation(s) in RCA: 133] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Accepted: 05/14/2014] [Indexed: 01/01/2023] Open
Abstract
Non-invasive brain stimulation (NIBS) may enhance motor recovery after neurological injury through the causal induction of plasticity processes. Neurological injury, such as stroke, often results in serious long-term physical disabilities, and despite intensive therapy, a large majority of brain injury survivors fail to regain full motor function. Emerging research suggests that NIBS techniques, such as transcranial magnetic (TMS) and direct current (tDCS) stimulation, in association with customarily used neurorehabilitative treatments, may enhance motor recovery. This paper provides a general review on TMS and tDCS paradigms, the mechanisms by which they operate and the stimulation techniques used in neurorehabilitation, specifically stroke. TMS and tDCS influence regional neural activity underlying the stimulation location and also distant interconnected network activity throughout the brain. We discuss recent studies that document NIBS effects on global brain activity measured with various neuroimaging techniques, which help to characterize better strategies for more accurate NIBS stimulation. These rapidly growing areas of inquiry may hold potential for improving the effectiveness of NIBS-based interventions for clinical rehabilitation.
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Affiliation(s)
- Sook-Lei Liew
- Human Cortical Physiology and Neurorehabilitation Section, National Institute of Neurological Disorders and Stroke, NIH Bethesda, MD, USA
| | | | - Ethan R Buch
- Human Cortical Physiology and Neurorehabilitation Section, National Institute of Neurological Disorders and Stroke, NIH Bethesda, MD, USA ; Center for Neuroscience and Regenerative Medicine, Uniformed Services University of Health Sciences Bethesda, MD, USA
| | - Leonardo G Cohen
- Human Cortical Physiology and Neurorehabilitation Section, National Institute of Neurological Disorders and Stroke, NIH Bethesda, MD, USA ; Center for Neuroscience and Regenerative Medicine, Uniformed Services University of Health Sciences Bethesda, MD, USA
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249
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Oral fingolimod reduces glutamate-mediated intracortical excitability in relapsing-remitting multiple sclerosis. Clin Neurophysiol 2014; 126:165-9. [PMID: 25022794 DOI: 10.1016/j.clinph.2014.05.031] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Revised: 04/23/2014] [Accepted: 05/05/2014] [Indexed: 12/30/2022]
Abstract
OBJECTIVE Fingolimod is an effective disease modifying therapy for multiple sclerosis (MS). Beyond its main action on peripheral lymphocytes, several noteworthy side effects have been demonstrated in vitro, among which modulation of neural excitability. Our aim was to explore cortical excitability in vivo in patients treated with fingolimod 0.5mg/day. METHODS Paired-pulse TMS was applied on the left primary motor cortex in 13 patients affected by relapsing-remitting MS, the day before the first dose of fingolimod (T0) and 60days later (T1). Resting motor threshold, baseline motor evoked potentials, short interval intracortical inhibition (at 1, 3, 5ms) and intracortical facilitation (at 7, 9, 11 and 13ms) were estimated at T0 and T1. RESULTS Intracortical facilitation was reduced at T1, without any changes in short interval intracortical inhibition. CONCLUSIONS Fingolimod selectively reduced intracortical facilitation, which is mainly mediated by glutamate. SIGNIFICANCE This is the first in vivo confirmation of the effects of fingolimod on glutamatergic drive in treated humans. Our results suggest a novel neuromodulatory activity of fingolimod with potential effect on glutamate-mediated excitotoxicity in vivo, as already seen in animal models.
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Carmel JB, Martin JH. Motor cortex electrical stimulation augments sprouting of the corticospinal tract and promotes recovery of motor function. Front Integr Neurosci 2014; 8:51. [PMID: 24994971 PMCID: PMC4061747 DOI: 10.3389/fnint.2014.00051] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 05/28/2014] [Indexed: 12/11/2022] Open
Abstract
The corticospinal system—with its direct spinal pathway, the corticospinal tract (CST) – is the primary system for controlling voluntary movement. Our approach to CST repair after injury in mature animals was informed by our finding that activity drives establishment of connections with spinal cord circuits during postnatal development. After incomplete injury in maturity, spared CST circuits sprout, and partially restore lost function. Our approach harnesses activity to augment this injury-dependent CST sprouting and to promote function. Lesion of the medullary pyramid unilaterally eliminates all CST axons from one hemisphere and allows examination of CST sprouting from the unaffected hemisphere. We discovered that 10 days of electrical stimulation of either the spared CST or motor cortex induces CST axon sprouting that partially reconstructs the lost CST. Stimulation also leads to sprouting of the cortical projection to the magnocellular red nucleus, where the rubrospinal tract originates. Coordinated outgrowth of the CST and cortical projections to the red nucleus could support partial re-establishment of motor systems connections to the denervated spinal motor circuits. Stimulation restores skilled motor function in our animal model. Lesioned animals have a persistent forelimb deficit contralateral to pyramidotomy in the horizontal ladder task. Rats that received motor cortex stimulation either after acute or chronic injury showed a significant functional improvement that brought error rate to pre-lesion control levels. Reversible inactivation of the stimulated motor cortex reinstated the impairment demonstrating the importance of the stimulated system to recovery. Motor cortex electrical stimulation is an effective approach to promote spouting of spared CST axons. By optimizing activity-dependent sprouting in animals, we could have an approach that can be translated to the human for evaluation with minimal delay.
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Affiliation(s)
- Jason B Carmel
- Department of Neurology, Weill Cornell Medical College New York, NY, USA ; Department of Pediatrics, Weill Cornell Medical College New York, NY, USA ; Brain and Mind Research Institute, Weill Cornell Medical College New York, NY, USA ; Burke Medical Research Institute White Plains, NY, USA
| | - John H Martin
- Department of Physiology, Pharmacology and Neuroscience, City College of the City University of New York New York, NY, USA
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