Familiarity with a Tool Influences Peripersonal Space and Primary Motor Cortex Excitability of Muscles Involved in Haptic Contact

Abstract Long-term experience with a tool stably enlarges peripersonal space (PPS). Also, gained experience with a tool modulates internal models of action. The aim of this work was to understand whether the familiarity with a tool influences both PPS and motor representation. Toward this goal, we tested in 13 expert fencers through a multisensory integration paradigm the embodiment in their PPS of a personal (pE) or a common (cE) épée. Then, we evaluated the primary motor cortex excitability of proximal (ECR) and distal (APB) muscles during a motor imagery (MI) task of an athletic gesture when athletes handled these tools. Results showed that pE enlarges subjects’ PPS, while cE does not. Moreover, during MI, handling tools increased cortical excitability of ECR muscle. Notably, APB’s cortical excitability during MI only increased with pE as a function of its embodiment in PPS. These findings indicate that the familiarity with a tool specifically enlarges PPS and modulates the cortical motor representation of those muscles involved in the haptic contact with it.

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Long-term effect of safinamide on primary motor cortex excitability and plasticity in Parkinson's disease: A TMS study

Journal of the Neurological Sciences ◽

10.1016/j.jns.2021.119453 ◽

2021 ◽

Vol 429 ◽

pp. 119453

Author(s):

Valentina D'Onofrio ◽

Andrea Guerra ◽

Francesco Asci ◽

Giovanni Fabbrini ◽

Alfredo Berardelli ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Motor Cortex ◽

Primary Motor Cortex ◽

Term Effect ◽

Long Term Effect ◽

Motor Cortex Excitability

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Expanding the parameter space of anodal transcranial direct current stimulation of the primary motor cortex

Scientific Reports ◽

10.1038/s41598-019-54621-0 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 10

Author(s):

Desmond Agboada ◽

Mohsen Mosayebi Samani ◽

Asif Jamil ◽

Min-Fang Kuo ◽

Michael A. Nitsche

Keyword(s):

Motor Cortex ◽

Parameter Space ◽

Primary Motor Cortex ◽

Cortical Excitability ◽

Motor Evoked Potentials ◽

Anodal Tdcs ◽

Stimulation Parameters ◽

Motor Cortex Excitability ◽

The Impact ◽

Motor Cortex Plasticity

AbstractSize and duration of the neuroplastic effects of tDCS depend on stimulation parameters, including stimulation duration and intensity of current. The impact of stimulation parameters on physiological effects is partially non-linear. To improve the utility of this intervention, it is critical to gather information about the impact of stimulation duration and intensity on neuroplasticity, while expanding the parameter space to improve efficacy. Anodal tDCS of 1–3 mA current intensity was applied for 15–30 minutes to study motor cortex plasticity. Sixteen healthy right-handed non-smoking volunteers participated in 10 sessions (intensity-duration pairs) of stimulation in a randomized cross-over design. Transcranial magnetic stimulation (TMS)-induced motor-evoked potentials (MEP) were recorded as outcome measures of tDCS effects until next evening after tDCS. All active stimulation conditions enhanced motor cortex excitability within the first 2 hours after stimulation. We observed no significant differences between the three stimulation intensities and durations on cortical excitability. A trend for larger cortical excitability enhancements was however observed for higher current intensities (1 vs 3 mA). These results add information about intensified tDCS protocols and suggest that the impact of anodal tDCS on neuroplasticity is relatively robust with respect to gradual alterations of stimulation intensity, and duration.

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Plasticity of the Cortical Motor System

Journal of Human Kinetics ◽

10.2478/v10078-008-0014-x ◽

2008 ◽

Vol 20 (1) ◽

pp. 5-22 ◽

Cited By ~ 3

Author(s):

Bogdan Sadowski

Keyword(s):

Motor Cortex ◽

Motor System ◽

Primary Motor Cortex ◽

Pyramidal Neurons ◽

Pyramidal Cells ◽

Long Term Potentiation ◽

Skill Learning ◽

Dynamic Features ◽

Cortical Motor

Plasticity of the Cortical Motor SystemThe involvement of brain plastic mechanisms in the control of motor functions under normal and pathological conditions is described. These mechanisms are based on a similar principle as the neuronal models of neuronal plasticity - long-term potentiation (LTP), and long-term depression (LTD). In the motor cortex, LTP-like phenomena play a role in strengthening synaptic connections between pyramidal neurons. LTD is important for the elimination of unnecessary inputs to the cortex. The dynamic features of the primary motor cortex activity depend on particular neuronal interconnectivity within this area. The pyramidal cells send horizontal collaterals to adjacent subregions of the primary motor cortex, and so can either excite or inhibit remote pyramidal cells. These connections can expand or shrink depending on actual physiological demands, and play a role in skill learning.

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Reliability of robotic transcranial magnetic stimulation motor mapping

Journal of Neurophysiology ◽

10.1152/jn.00527.2020 ◽

2021 ◽

Vol 125 (1) ◽

pp. 74-85

Author(s):

Adrianna Giuffre ◽

Cynthia K. Kahl ◽

Ephrem Zewdie ◽

James G. Wrightson ◽

Anna Bourgeois ◽

...

Keyword(s):

Transcranial Magnetic Stimulation ◽

Motor Cortex ◽

Magnetic Stimulation ◽

Primary Motor Cortex ◽

Motor Mapping ◽

Cortical Motor ◽

Short And Long Term ◽

Motor Maps ◽

Absolute Reliability

Robotic transcranial magnetic stimulation (TMS) is a noninvasive and safe tool that produces cortical motor maps—individualized representations of the primary motor cortex (M1) topography—that may reflect developmental and interventional plasticity. This study is the first to evaluate short- and long-term relative and absolute reliability of TMS mapping outcomes at various M1 excitability levels using novel robotic neuronavigated TMS.

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Comparison of low frequency repetitive transcranial magnetic stimulation parameters on motor cortex excitability in normal subjects

International Journal of Epilepsy ◽

10.1016/j.ijep.2016.02.003 ◽

2016 ◽

Vol 03 (01) ◽

pp. 002-006

Author(s):

Lara Schrader ◽

Sima Sadeghinejad ◽

Jalleh Sadeghinejad ◽

Movses Kazanchyan ◽

Lisa Koski ◽

...

Keyword(s):

Transcranial Magnetic Stimulation ◽

Motor Cortex ◽

Magnetic Stimulation ◽

Primary Motor Cortex ◽

Cortical Excitability ◽

Repetitive Transcranial Magnetic Stimulation ◽

Low Frequency ◽

Motor Threshold ◽

Motor Cortex Excitability ◽

Resting Motor Threshold

Abstract Background/objectives Optimal low frequency repetitive transcranial magnetic stimulation (LF-rTMS) parameters for treating epilepsy and other brain disorders are unknown. To address this question, a systematic study of the effects of LF-rTMS frequency and intensity on cortical excitability was performed. Methods Using a four-period crossover design, subjects were scheduled for four LF-rTMS sessions that were at least four weeks apart. LF-rTMS was delivered as 900 pulses directed at primary motor cortex using four protocols: 0.5 Hz at 90% resting motor threshold (RMT), 0.5 Hz at 110% RMT, 1 Hz at 90% RMT, and 1 Hz at 110% RMT. Motor evoked potential (MEP) amplitude, resting motor threshold (RMT), and cortical silent period (CSP) were measured before, immediately after, and 60 min after LF-rTMS. Each of the four protocols was analyzed separately to compare baseline measurements to those after LF-rTMS. Results None of the four LF-rTMS protocols produced a trend or significant change in MEP amplitude, RMT, or CSP. Conclusion The lack of significant effect from the four LF-rTMS protocols indicates that none produced evidence for alteration of cortical excitability. The direct comparison of four LF-rTMS protocols is distinct to this investigation, as most similar studies were exploratory and studied only one or two protocols. The negative result relates only to the methods used in this investigation and does not indicate that LF-rTMS does not alter cortical excitability with other parameters. These results may be useful when designing additional investigations into the effect of LF-rTMS on epilepsy, other disorders, and cortical excitability.

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BDNF polymorphism and inter hemispheric balance of motor cortex excitability: a preliminary study

Journal of Neurophysiology ◽

10.1152/jn.00268.2021 ◽

2021 ◽

Author(s):

Raffaele Dubbioso ◽

Giovanni Pellegrino ◽

Federico Ranieri ◽

Giovanni Di Pino ◽

Fioravante Capone ◽

...

Keyword(s):

Motor Cortex ◽

Primary Motor Cortex ◽

Cortical Excitability ◽

Short Interval ◽

Intracortical Inhibition ◽

Val66met Polymorphism ◽

Healthy Humans ◽

Motor Cortex Excitability ◽

Active Motor ◽

Bdnf Val66met Polymorphism

Preclinical studies have demonstrated that Brain-Derived Neurotrophic Factor (BDNF) plays a crucial role in the homeostatic regulation of cortical excitability and excitation/inhibition balance. Using transcranial magnetic stimulation (TMS) techniques we investigated whether BDNF polymorphism could influence cortical excitability of the left and right primary motor cortex in healthy humans. Twenty-nine participants were recruited and genotyped for the presence of the BDNF Val66Met polymorphism, namely homozygous for the valine allele (Val/Val), heterozygotes (Val/Met), and homozygous for the methionine allele (Met/Met). Blinded to the latter, we evaluated inhibitory and facilitatory circuits of the left (LH) and right motor cortex (RH) by measuring resting (RMT) and active motor threshold (AMT), short interval intracortical inhibition (SICI) and intracortical facilitation (ICF). For each neurophysiological metric we also considered the inter-hemispheric balance expressed by the Laterality Index (LI). Val/Val participants (n= 21) exhibited an overall higher excitability of the LH compared to the RH, as probed by lower motor thresholds, lower SICI and higher ICF. Val/Val participants displayed positive LI, especially for AMT and ICF (all p< 0.05), indicating higher LH excitability and more pronounced inter-hemispheric excitability imbalance as compared to Met carriers. Our preliminary results suggest that BDNF Val66Met polymorphism might influence interhemispheric balance of motor cortex excitability.

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Effects of transcranial static magnetic stimulation over the primary motor cortex on local and network spontaneous electroencephalogram oscillations

Scientific Reports ◽

10.1038/s41598-021-87746-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sumiya Shibata ◽

Tatsunori Watanabe ◽

Yoshihiro Yukawa ◽

Masatoshi Minakuchi ◽

Ryota Shimomura ◽

...

Keyword(s):

Motor Cortex ◽

Power Spectrum ◽

Magnetic Stimulation ◽

Primary Motor Cortex ◽

Cortical Excitability ◽

Controlled Study ◽

Functional Coupling ◽

Phase Lag ◽

Theta Band ◽

Double Blind

AbstractTranscranial static magnetic stimulation (tSMS) is a novel non-invasive brain stimulation technique that reduces cortical excitability at the stimulation site. We investigated the effects of tSMS over the left primary motor cortex (M1) for 20 min on the local electroencephalogram (EEG) power spectrum and interregional EEG coupling. Twelve right-handed healthy subjects participated in this crossover, double-blind, sham-controlled study. Resting-state EEG data were recorded for 3 min before the intervention and 17 min after the beginning of the intervention. The power spectrum at the left central electrode (C3) and the weighted phase lag index (wPLI) between C3 and the other electrodes was calculated for theta (4–8 Hz), alpha (8–12 Hz), and beta (12–30 Hz) frequencies. The tSMS significantly increased theta power at C3 and the functional coupling in the theta band between C3 and the parietal midline electrodes. The tSMS over the left M1 for 20 min exhibited modulatory effects on local cortical activity and interregional functional coupling in the theta band. The neural oscillations in the theta band may have an important role in the neurophysiological effects induced by tSMS over the frontal cortex.

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Cerebellar rTMS and PAS effectively induce cerebellar plasticity

Scientific Reports ◽

10.1038/s41598-021-82496-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Martje G. Pauly ◽

Annika Steinmeier ◽

Christina Bolte ◽

Feline Hamami ◽

Elinor Tzvi ◽

...

Keyword(s):

Motor Cortex ◽

Healthy Subjects ◽

Primary Motor Cortex ◽

Cortical Excitability ◽

Motor Evoked Potentials ◽

Repetitive Transcranial Magnetic Stimulation ◽

Premotor Cortex ◽

Motor Pathways ◽

Non Invasive ◽

Cerebellar Plasticity

AbstractNon-invasive brain stimulation techniques including repetitive transcranial magnetic stimulation (rTMS), continuous theta-burst stimulation (cTBS), paired associative stimulation (PAS), and transcranial direct current stimulation (tDCS) have been applied over the cerebellum to induce plasticity and gain insights into the interaction of the cerebellum with neo-cortical structures including the motor cortex. We compared the effects of 1 Hz rTMS, cTBS, PAS and tDCS given over the cerebellum on motor cortical excitability and interactions between the cerebellum and dorsal premotor cortex / primary motor cortex in two within subject designs in healthy controls. In experiment 1, rTMS, cTBS, PAS, and tDCS were applied over the cerebellum in 20 healthy subjects. In experiment 2, rTMS and PAS were compared to sham conditions in another group of 20 healthy subjects. In experiment 1, PAS reduced cortical excitability determined by motor evoked potentials (MEP) amplitudes, whereas rTMS increased motor thresholds and facilitated dorsal premotor-motor and cerebellum-motor cortex interactions. TDCS and cTBS had no significant effects. In experiment 2, MEP amplitudes increased after rTMS and motor thresholds following PAS. Analysis of all participants who received rTMS and PAS showed that MEP amplitudes were reduced after PAS and increased following rTMS. rTMS also caused facilitation of dorsal premotor-motor cortex and cerebellum-motor cortex interactions. In summary, cerebellar 1 Hz rTMS and PAS can effectively induce plasticity in cerebello-(premotor)-motor pathways provided larger samples are studied.

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Effect of opposing needling on motor cortex excitability in healthy participants and in patients with post-stroke hemiplegia: study protocol for a single-blind, randomised controlled trial

Trials ◽

10.1186/s13063-021-05443-x ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Mindong Xu ◽

Yinyu Zi ◽

Jianlu Wu ◽

Nenggui Xu ◽

Liming Lu ◽

...

Keyword(s):

Motor Cortex ◽

Primary Motor Cortex ◽

Motor Evoked Potentials ◽

Controlled Trial ◽

Secondary Outcome ◽

Post Stroke ◽

Motor Cortex Excitability ◽

Opposing Needling ◽

Single Blind ◽

Healthy Participants

Abstract Background Opposing needling has an obvious curative effect in the treatment of post-stroke hemiplegia; however, the mechanism of the opposing needling in the treatment of post-stroke hemiplegia is still not clear. The purpose of this study is to investigate the effect of opposing needling on the excitability of primary motor cortex (M1) of healthy participants and patients with post-stroke hemiplegia, which may provide insight into the mechanisms of opposing needling in treating post-stroke hemiplegia. Methods This will be a single-blind, randomised, sham-controlled trial in which 80 healthy participants and 40 patients with post-stroke hemiplegia will be recruited. Healthy participants will be randomised 1:1:1:1 to the 2-Hz, 50-Hz, 100-Hz, and sham electroacupuncture groups. Patients with post-stroke hemiplegia will be randomised 1:1 to the opposing needling or conventional treatment groups. The M1 will be located in all groups by using neuroimaging-based navigation. The stimulator coil of transcranial magnetic stimulation (TMS) will be moved over the left and right M1 in order to identify the TMS hotspot, followed by a recording of resting motor thresholds (RMTs) and motor-evoked potentials (MEPs) of the thenar muscles induced by TMS before and after the intervention. The primary outcome measure will be the percent change in the RMTs of the thenar muscles at baseline and after the intervention. The secondary outcome measures will be the amplitude (μV) and latency (ms) of the MEPs of the thenar muscles at baseline and after the intervention. Discussion The aim of this trial is to explore the effect of opposing needling on the excitability of M1 of healthy participants and patients with post-stroke hemiplegia. Trial registration Chinese Clinical Trial Registry ChiCTR1900028138. Registered on 13 December 2019.

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Online and offline effects of transcranial alternating current stimulation of the primary motor cortex

Scientific Reports ◽

10.1038/s41598-021-83449-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ivan Pozdniakov ◽

Alicia Nunez Vorobiova ◽

Giulia Galli ◽

Simone Rossi ◽

Matteo Feurra

Keyword(s):

Motor Cortex ◽

Primary Motor Cortex ◽

Cortical Excitability ◽

Motor Evoked Potentials ◽

Random Noise ◽

Single Pulse ◽

Alternating Current ◽

Online Application ◽

Transcranial Random Noise Stimulation ◽

Transcranial Alternating Current Stimulation

AbstractTranscranial alternating current stimulation (tACS) is a non-invasive brain stimulation technique that allows interaction with endogenous cortical oscillatory rhythms by means of external sinusoidal potentials. The physiological mechanisms underlying tACS effects are still under debate. Whereas online (e.g., ongoing) tACS over the motor cortex induces robust state-, phase- and frequency-dependent effects on cortical excitability, the offline effects (i.e. after-effects) of tACS are less clear. Here, we explored online and offline effects of tACS in two single-blind, sham-controlled experiments. In both experiments we used neuronavigated transcranial magnetic stimulation (TMS) of the primary motor cortex (M1) as a probe to index changes of cortical excitability and delivered M1 tACS at 10 Hz (alpha), 20 Hz (beta) and sham (30 s of low-frequency transcranial random noise stimulation; tRNS). Corticospinal excitability was measured by single pulse TMS-induced motor evoked potentials (MEPs). tACS was delivered online in Experiment 1 and offline in Experiment 2. In Experiment 1, the increase of MEPs size was maximal with the 20 Hz stimulation, however in Experiment 2 neither the 10 Hz nor the 20 Hz stimulation induced tACS offline effects. These findings support the idea that tACS affects cortical excitability only during online application, at least when delivered on the scalp overlying M1, thereby contributing to the development of effective protocols that can be applied to clinical populations.

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