29,099 results match your criteria: "Motor Evoked Potentials"

Objectives: Motor evoked potential (MEP) monitoring is a reliable method for real-time assessment of corticospinal tract integrity. However, the potential benefits of MEP monitoring during degenerative spine surgery remain controversial. This study aims to determine the role of MEP monitoring during surgery for cervical spondylotic myelopathy (CSM) in prediction of prognosis.

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  • * A study using low-intensity transcranial magnetic stimulation showed that individuals with SCI had prolonged suppression of voluntary electromyographic activity (svEMG) in their triceps, indicating increased intracortical inhibition during elbow extension.
  • * The findings suggest stronger inhibitory inputs to the corticospinal pathways for elbow extensors in those with SCI, highlighting the challenges in regaining function after such injuries.
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  • * Researchers measured central motor conduction time (CMCT) in different groups, including MS patients with and without the McArdle sign, other myelopathy patients, and healthy controls.
  • * Results showed that MS patients with a prominent McArdle sign displayed significantly prolonged CMCT during neck flexion, suggesting that the sign may be linked to nerve conduction slowing due to demyelination.
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  • Traumatic spinal cord injury (SCI) leads to serious physical, psychological, and work-related challenges for both patients and their caregivers, necessitating effective treatment options.
  • Heterophyllin B (HB), a cyclopeptide that can cross the blood-brain barrier, was evaluated in a mouse model to determine its potential in promoting recovery and understanding its mechanisms after SCI.
  • The study found that HB enhances functional recovery by stimulating autophagy through the transcription factor EB (TFEB), while also reducing harmful processes like pyroptosis and oxidative stress, suggesting its future clinical relevance.
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  • - The study focused on how parieto-motor paired stimulation affects brain plasticity in patients with writer's cramp (WC) and cervical dystonia (CD) compared to healthy volunteers.
  • - Using paired transcranial magnetic stimulation, researchers found that the stimulation increased motor cortex excitability in WC patients but not in CD patients or healthy individuals.
  • - The results indicate that while the stimulation enhances brain function in WC, it doesn't seem to relate to changes in the connectivity between the posterior parietal cortex and the motor cortex.
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Long-term motor learning in focal hand dystonia.

Clin Neurophysiol

December 2024

Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA. Electronic address:

Objective: Because focal hand dystonia usually occurs in the over-learned stage, it would be valuable to know long-term motor learning characteristics and underlying pathophysiological features that might predispose to dystonia.

Methods: We conducted a case-control exploratory study of 15 visits over 12 weeks in the non-affected hand of a 4-finger sequence of 8 key presses in eight patients with FHD compared with eight age- and sex-matched, healthy volunteers (HVs). We studied the behavioral data and the physiological changes of the brain, including motor cortical excitability and cortical oscillations.

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  • This study focused on using vestibular evoked myogenic potentials (VEMPs) to evaluate otolith function in patients with unilateral vestibular schwannoma before surgery, measuring specific metrics like amplitudes, latencies, and threshold levels.
  • Out of 27 participants, cVEMP was obtained from 89% and oVEMP from 74%, showing significant differences in cVEMP amplitudes and thresholds in patients with inferior vestibular nerve origin.
  • The findings indicated increased p13 latency in the affected ear, but overall, the small sample size limited the ability for robust statistical conclusions, making the results exploratory in nature.
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Visualizing Intraoperative Transcranial Motor-Evoked Potentials During Glioma Surgery for Predicting Postoperative Paralysis Prognosis.

World Neurosurg

November 2024

Department of Neurosurgery, Tokyo Women's Medical University, Shinjuku City, Japan; Faculty of Advanced Techno-Surgery, Institute of Advanced Biomedical Engineering and Science, Graduate School of Medicine, Tokyo Women's Medical University, Shinjuku City, Japan; Center for Advanced Medical Engineering Research and Development, Kobe University, Kobe City, Japan.

Objective: The primary goals of glioma surgery are maximal tumor resection and preservation of brain function. Intraoperative motor-evoked potential (MEP) monitoring is commonly used to predict and minimize postoperative paralysis. However, studies on intraoperative MEP trends and postoperative paralysis are scarce.

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This study aimed to investigate whether the cerebellum contributes to contraction-induced facilitation (CIF) of contralateral corticospinal excitability. To this end, repetitive cerebellar transcranial magnetic stimulation (TMS) was used to test whether it modulates CIF. Overall, 20 healthy young individuals participated in the study.

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Notwithstanding advances in computational models of neuromodulation, there are mismatches between simulated and experimental activation thresholds. Transcranial Magnetic Stimulation (TMS) of the primary motor cortex generates motor evoked potentials (MEPs). At the threshold of MEP generation, whole-head models predict macroscopic (at millimeter scale) electric fields (50-70 V/m) which are considerably below conventionally simulated cortical neuron thresholds (200-300 V/m).

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F-waves responses derived from low-intensity electrical stimulation: A method to explore split-hand pathogenesis.

Neurophysiol Clin

November 2024

Institute of Physiology, Instituto de Medicina Molecular João Lobo Antunes, Centro de Estudos Egas Moniz, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal; Department of Neurosciences and Mental Health, Hospital de Santa Maria, Centro Hospitalar Universitário de Lisboa Norte, Lisbon, Portugal. Electronic address:

Objectives: The "split-hand syndrome" is a common clinical sign in amyotrophic lateral sclerosis (ALS), being characterized by more severe atrophy of the hand muscles on the radial side of the hand compared to the ulnar side. We aimed to investigate possible physiological differences between relevant hand muscles using low-intensity F-wave stimulation to assess spinal motoneuron excitability.

Methods: We recruited 36 healthy volunteers.

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Ischaemic spinal cord injury remains a significant challenge in thoracoabdominal aortic repairs. Modern techniques have reduced spinal cord injury rates yet managing patients during and after thoracoabdominal aortic repairs remains complex. This article outlines our comprehensive approach to the prevention of spinal cord injuries in open thoracoabdominal aortic repair operations, focusing on the placement of cerebrospinal fluid drain and intraoperative strategies to enhance spinal cord protection.

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Effects of cervical transcutaneous spinal direct current stimulation on spinal excitability.

Clin Neurophysiol

December 2024

Brain Connectivity Laboratory, Dept. Neuroscience & Neurorehabilitation, IRCCS San Raffaele, Rome, Italy. Electronic address:

Article Synopsis
  • The study investigates the effects of transcutaneous spinal direct current stimulation (tsDCS) on spinal cord excitability through a randomized, sham-controlled experiment involving 18 young participants.
  • It found that a specific electrode configuration (anode on the 7th cervical spinous process and cathode on the glottis) significantly enhanced motor responses in hand muscles when stimulated, particularly noticeable during tsDCS and plateauing after six minutes.
  • These results indicate that tsDCS may enhance motoneuron excitability, suggesting potential therapeutic applications for individuals with impaired hand motor function due to corticospinal fiber issues.
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Dexmedetomidine Versus Fentanyl in Intraoperative Neuromuscular Monitoring Using A Propofol-based Total Intravenous Anaesthesia Regimen in Spine Surgeries.

Turk J Anaesthesiol Reanim

October 2024

Mahatma Gandhi Medical College & Hospital, Mahatma Gandhi University of Medical Sciences & Technology, Jaipur, Clinic of Community Medicine, Division of Biostatistics, Jaipur, India.

Article Synopsis
  • A study compared dexmedetomidine and fentanyl's effects on motor evoked potentials during spine surgery under propofol-based anesthesia.
  • Both drugs showed similar results on TcMEP latency and amplitude, but dexmedetomidine led to a longer extubation time and shorter recovery stay.
  • Dexmedetomidine also reduced total propofol consumption and improved surgical field quality compared to fentanyl.
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Background: Proprioceptive deficits have been shown to underlie motor problems in individuals with a probable developmental coordination disorder (pDCD). Behavioral studies have employed response times to passive limb movement to evaluate proprioceptive function in individuals with pDCD. However, the underlying neural mechanisms involved in the cortical processing of proprioceptive input and its corresponding motor response are unclear.

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  • Clinical studies on repetitive transcranial magnetic stimulation (rTMS) show inconsistent results, possibly due to differences in study methods, prompting a review of preclinical rTMS protocols in mice for epilepsy research.
  • A comprehensive search identified 23 relevant studies that used various epilepsy induction methods and defined motor thresholds, exploring the effects of different rTMS frequencies on seizure activity.
  • Findings indicate that low-frequency rTMS (≤5 Hz) generally suppresses seizures and improves behavioral outcomes, while high-frequency rTMS (≥5 Hz) had mixed effects, highlighting the importance of stimulation frequency in optimizing clinical applications for epilepsy treatment.
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Anodal tDCS improves neuromuscular adaptations to short-term resistance training of the knee extensors in healthy individuals.

J Neurophysiol

December 2024

Department of Sport, Exercise and Rehabilitation, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, United Kingdom.

Experimental studies show improvement in physical performance following acute application of transcranial direct current stimulation (tDCS). This study examined the neuromuscular and neural responses to a single training session () and following a 3 wk resistance training program () performed with the knee extensors, preceded by tDCS over the primary motor cortex. Twenty-four participants (age, 30 ± 7 yr; stature, 172 ± 8 cm; mass, 72 ± 15 kg) were randomly allocated to perform either resistance training with anodal tDCS (a-tDCS) or a placebo tDCS (Sham).

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Background: To gain a comprehensive understanding of the altered sensory processing in patients with migraine, in this study, we developed an electroencephalography (EEG) protocol for examining brainstem and cortical responses to sensory stimulation. Furthermore, machine learning techniques were employed to identify neural signatures from evoked brainstem-cortex activation and their interactions, facilitating the identification of the presence and subtype of migraine.

Methods: This study analysed 1,000-epoch-averaged somatosensory evoked responses from 342 participants, comprising 113 healthy controls (HCs), 106 patients with chronic migraine (CM), and 123 patients with episodic migraine (EM).

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Rehabilitation devices, such as traditional rigid exoskeletons or exosuits, have been widely used to rehabilitate upper limb function post-stroke. In this paper, we have developed an exosuit with four degrees of freedom to enable users to involve more joints in the rehabilitation process. Additionally, a hybrid electroencephalogram-based (EEG-based) control approach has been developed to promote active user engagement and provide more control commands.

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Background: Low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) protocols targeting primary motor cortex (M1) are used in rehabilitation of neurological diseases for their therapeutic potential, safety, and tolerability. Although lower intensity LF-rTMS can modulate M1 neurophysiology, results are variable, and a systematic assessment of its dose effect is lacking.

Objectives: To determine the dose-response of LF-rTMS on stimulated and non-stimulated M1.

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Methodological Choices Matter: A Systematic Comparison of TMS-EEG Studies Targeting the Primary Motor Cortex.

Hum Brain Mapp

October 2024

Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital-Amager and Hvidovre, Hvidovre, Denmark.

Transcranial magnetic stimulation (TMS) triggers time-locked cortical activity that can be recorded with electroencephalography (EEG). Transcranial evoked potentials (TEPs) are widely used to probe brain responses to TMS. Here, we systematically reviewed 137 published experiments that studied TEPs elicited from TMS to the human primary motor cortex (M1) in healthy individuals to investigate the impact of methodological choices.

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Spatiotemporal Mapping of Auditory Onsets during Speech Production.

J Neurosci

November 2024

Department of Speech, Language, and Hearing Sciences, Moody College of Communication, The University of Texas at Austin, Austin, Texas 78712

The human auditory cortex is organized according to the timing and spectral characteristics of speech sounds during speech perception. During listening, the posterior superior temporal gyrus is organized according to onset responses, which segment acoustic boundaries in speech, and sustained responses, which further process phonological content. When we speak, the auditory system is actively processing the sound of our own voice to detect and correct speech errors in real time.

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