Search results for "Silent period"
showing 10 items of 22 documents
Novel Insights of Effects of Pregabalin on Neural Mechanisms of Intracortical Disinhibition in Physiopathology of Fibromyalgia: An Explanatory, Rando…
2018
Submitted by DSpace Unilasalle (dspace@unilasalle.edu.br) on 2021-09-14T16:51:25Z No. of bitstreams: 1 adeitos.etal.pdf: 2278622 bytes, checksum: dd96bf75fdbab601238c2831da009c73 (MD5) Made available in DSpace on 2021-09-14T16:51:25Z (GMT). No. of bitstreams: 1 adeitos.etal.pdf: 2278622 bytes, checksum: dd96bf75fdbab601238c2831da009c73 (MD5) Previous issue date: 2018 Background: The fibromyalgia (FM) physiopathology involves an intracortical excitability/inhibition imbalance as measured by transcranial magnetic stimulation measures (TMS). TMS measures provide an index that can help to understand how the basal neuronal plasticity state (i.e., levels of the serum neurotrophins brain-derived n…
Interhemispheric inhibition is dynamically regulated during action observation
2016
International audience; It is now well established that the motor system plays a pivotal role in action observation and that the neurophysiological processes underlying perception and action overlaps. However, while various experiments have shown a specific facilitation of the contralateral motor cortex during action observation, no information is available concerning the dynamics of interhemispheric interactions. The aim of the present study was, therefore, to assess interhemispheric inhibition during the observation of others' actions. We designed a transcranial magnetic stimulation (TMS) experiment in which we measured both corticospinal excitability and interhemispheric inhibition, this…
Increased facilitation of the primary motor cortex following 1 Hz repetitive transcranial magnetic stimulation of the contralateral cerebellum in nor…
2005
Connections between the cerebellum and the contralateral motor cortex are dense and important, but their physiological significance is difficult to measure in humans. We have studied a group of 10 healthy subjects to test whether a modulation of the excitability of the left cerebellum can affect the excitability of the contralateral motor cortex. We used repetitive transcranial magnetic stimulation (rTMS) at 1 Hz frequency to transiently depress the excitability of the left cerebellar cortex and paired-pulse TMS testing of intracortical inhibition (ICI) and intracortical facilitation (ICF) to probe the excitability of cortico-cortical connections in the right motor cortex. The cortical sile…
Modulation of intracortical inhibition induced by low- and high-frequency repetitive transcranial magnetic stimulation.
2001
We studied the changes of duration of subsequent silent periods (SPs) during repetitive magnetic stimulation (rTMS) trains of ten stimuli delivered at low (1 Hz) and high (7 Hz) frequencies. The effects at different intensities of stimulation (motor threshold, MT, 115% and 130% above the MT) were also evaluated. rTMS was performed in eight healthy subjects with a figure-of-eight coil placed over the hand motor area. The SP was recorded from abductor pollicis brevis (APB) muscle during a voluntary contraction of 30% of maximum effort. rTMS at 1-Hz frequency progressively decreased the duration of SP, whereas an alternating pattern of smaller and larger values was observed during trains at 7-…
Does the Recruitment of Excitation and Inhibition in the Motor Cortex Differ?
2007
The level of excitability within the motor cortex can be described as a balance between excitation and inhibition, but it is unknown how well both processes correlate. To address this question, the authors measured motor cortical excitability and inhibition in healthy human subjects, comparing the recruitment of motor evoked potentials (MEPs) and the duration of the cortical silent period (CSP) after transcranial magnetic stimulation (TMS). Single-pulse "focal" TMS was applied at intensities varying between 90% and 200% of motor thresholds to the right motor cortex of 15 healthy volunteers. The peak-to peak size of MEP responses and the duration of the CSP were measured in small hand muscle…
Specific modulation of spinal and cortical excitabilities during lengthening and shortening submaximal and maximal contractions in plantar flexor mus…
2014
This study investigated the influence of the torque produced by plantar flexor muscles on cortical and spinal excitability during lengthening and shortening voluntary contractions. To that purpose, modulations of motor-evoked potential (MEP) and Hoffmann (H) reflex were compared in the soleus (SOL) and medial gastrocnemius (MG) during anisometric submaximal and maximal voluntary contraction (MVC) of the plantar flexor muscles. For the submaximal shortening and lengthening contractions, the target torque was set at 50% of their respective MVC force. The results indicate that the amplitudes of both MEP and H-reflex responses, normalized to the maximal M wave, were significantly ( P < 0.05…
Determining the Corticospinal Responses to Single Bouts of Skill and Strength Training
2019
Mason, J, Frazer, AK, Jaberzadeh, S, Ahtiainen, JP, Avela, J, Rantalainen, T, Leung, M, and Kidgell, DJ. Determining the corticospinal responses to single bouts of skill and strength training. J Strength Cond Res 33(9): 2299-2307, 2019-Neuroplastic changes in the primary motor cortex accompany performance improvements following motor practice. Recent evidence suggests that the corticospinal responses to strength and skill training are similar, following both a single session and repeated bouts of training, promoting discussion that strength training is a form of motor learning. However, these findings are limited by the lack of a light-load strength training group. Therefore, the aim of the…
Increased cross-education of muscle strength and reduced corticospinal inhibition following eccentric strength training.
2015
Aim: Strength training of one limb results in a substantial increase in the strength of the untrained limb, however, it remains unknown what the corticospinal responses are following either eccentric or concentric strength training and how this relates to the cross-education of strength. The aim of this study was to determine if eccentric or concentric unilateral strength training differentially modulates corticospinal excitability, inhibition and the cross-transfer of strength. Methods: Changes in contralateral (left limb) concentric strength, eccentric strength, motor-evoked potentials, short-interval intracortical inhibition and silent period durations were analyzed in groups of young ad…
Transcranial magnetic stimulation reveals cortical hyperexcitability in episodic cluster headache
2014
Abstract Evidence shows involvement of the cerebral cortex in the pathophysiology of cluster headache (CH). Here we investigated cortical excitability in episodic CH patients by using transcranial magnetic stimulation. In 25 patients with episodic CH and 13 healthy subjects we evaluated the motor cortical response to single-pulse (ie, motor threshold, input-output curves, cortical silent period) and paired-pulse (ie, intracortical facilitation, short intracortical inhibition) transcranial magnetic stimulation in both hemispheres. Thirteen patients were evaluated outside bout and the remaining 12 patients inside bout. Our results showed increased slope of the input-output curves after stimul…
Tracking the corticospinal responses to strength training
2020
Purpose\ud The motor cortex (M1) appears to be a primary site of adaptation following both a single session, and repeated strength-training sessions across multiple weeks. Given that a single session of strength-training is sufficient to induce modification at the level of the M1 and corticospinal tract, this study sought to determine how these acute changes in M1 and corticospinal tract might accumulate across the course of a 2-week heavy-load strength-training program.\ud \ud Methods\ud Transcranial magnetic stimulation (TMS) was used to infer corticospinal excitability (CSE), intracortical facilitation (ICF), short and long-interval intracortical inhibition (SICI and LICI) and silent per…