F-wave and motor-evoked potentials during motor imagery and observation in apraxia of Parkinson disease

2015 ◽  
Vol 52 (6) ◽  
pp. 1072-1077 ◽  
Author(s):  
Ayşegül Gündüz ◽  
Meral E. Kiziltan
Keyword(s):  
Parkinson Disease ◽  
Evoked Potentials ◽  
Motor Imagery ◽  
Motor Evoked Potentials ◽  
F Wave

scholarly journals Motor Evoked Potentials after Supraspinal Stimulation in Pre- and Postoperative Evaluations of Patients with Cervical Radiculopathy

2019 ◽  
Vol 2019 ◽  
pp. 1-11
Author(s):  
Aleksandra Bryndal ◽  
Magdalena Wojtysiak ◽  
Jakub Moskal ◽  
Joanna Lipiec-Kowalska ◽  
Martyna Borowczyk ◽  
...  
Keyword(s):  
Clinical Trials ◽  
Muscle Strength ◽  
Evoked Potentials ◽  
Motor Evoked Potentials ◽  
Cervical Radiculopathy ◽  
Diagnostic Value ◽  
Pain Severity ◽  
Test And Evaluation ◽  
Neurophysiological Tests ◽  
F Wave

Objective. Pre- and postoperative comparative evaluation of neurophysiological tests and clinical trials. Analysis of the diagnostic value of motor evoked potentials (MEP) induced by a magnetic field after supraspinal stimulation. Evaluation of the sensitivity and specificity of electromyography (EMG) and MEP is achieved. Methods. EMG, ENG, M-wave, F-wave, and MEP tests were performed on 35 patients with confirmed cervical radiculopathy in pre- and postoperative evaluations. The clinical trial consisted of evaluation of muscle strength, a sensory perception test and evaluation of tendon reflexes and pain severity. Results. The sensitivity of the resting EMG and MEP tests is 24%-67% and 6%-27%, while their specificity is 43%-80% and 86%-100%, respectively. The postoperative evaluation revealed a statistically significant reduction in pain severity (p=0001), an increase in muscle strength in DP (p=0.0431), BB (p=0,0431), and TB (p=0.0272), and improvement of touch sensation in terms of dermatomal innervation in C5 (p=0.0001) and C6 (p=0.0044). Conclusions. Tests comparing MRI sensitivity to neurophysiological tests show that neuroimaging is more sensitive in diagnostics of patients with cervical radiculopathy; however, clinical neurophysiology tests are more specific in reference to clinical trials.

scholarly journals New evidence of corticospinal network modulation induced by motor imagery

2016 ◽  
Vol 115 (3) ◽  
pp. 1279-1288 ◽  
Author(s):  
Sidney Grosprêtre ◽  
Florent Lebon ◽  
Charalambos Papaxanthis ◽  
Alain Martin
Keyword(s):  
Evoked Potentials ◽  
Motor Imagery ◽  
Motor Evoked Potentials ◽  
Static Condition ◽  
Mental Simulation ◽  
Voluntary Contraction ◽  
H Reflex ◽  
Triceps Surae ◽  
Subcortical Structures ◽  
Reflex Amplitude

Motor imagery (MI) is the mental simulation of movement, without the corresponding muscle contraction. Whereas the activation of cortical motor areas during MI is established, the involvement of spinal structures is still under debate. We used original and complementary techniques to probe the influence of MI on spinal structures. Amplitude of motor-evoked potentials (MEPs), cervico-medullary-evoked potentials (CMEPs), and Hoffmann (H)-reflexes of the flexor carpi radialis (FCR) muscle and of the triceps surae muscles was measured in young, healthy subjects at rest and during MI. Participants were asked to imagine maximal voluntary contraction of the wrist and ankle, while the targeted limb was fixed (static condition). We confirmed previous studies with an increase of FCR MEPs during MI compared with rest. Interestingly, CMEPs, but not H-reflexes, also increased during MI, revealing a possible activation of subcortical structures. Then, to investigate the effect of MI on the spinal network, we used two techniques: 1) passive lengthening of the targeted muscle via an isokinetic dynamometer and 2) conditioning of H-reflexes with stimulation of the antagonistic nerve. Both techniques activate spinal inhibitory presynaptic circuitry, reducing the H-reflex amplitude at rest. In contrast, no reduction of H-reflex amplitude was observed during MI. These findings suggest that MI has modulatory effects on the spinal neuronal network. Specifically, the activation of low-threshold spinal structures during specific conditions (lengthening and H-reflex conditioning) highlights the possible generation of subliminal cortical output during MI.

An Increase in Cortical Excitability with No Change in Spinal Excitability during Motor Imagery

1996 ◽  
Vol 83 (1) ◽  
pp. 288-290 ◽  
Author(s):  
Susumu Yahagi ◽  
Kuniyoshi Shimura ◽  
Tatsuya Kasai
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
Evoked Potentials ◽  
Motor Imagery ◽  
Magnetic Stimulation ◽  
Cortical Excitability ◽  
Motor Evoked Potentials ◽  
Emg Activity ◽  
Electrical Stimuli ◽  
Spinal Excitability ◽  
Flexor Carpi Radialis Muscle

During motor imagery, to estimate changes in excitability of flexor carpi radialis muscle motoneurons of the spinal and cortical levels, electrical stimuli for recording H-reflex and transcranial magnetic stimulation (TMS) for recording motor evoked potentials (MEPs) were used. In the absence of movement or detectable EMG activity during motor magery, there was an increase in cortical excitability with no change in spinal excitability

Evidence for facilitation of motor evoked potentials (MEPs) induced by motor imagery

1997 ◽  
Vol 744 (1) ◽  
pp. 147-150 ◽  
Author(s):  
T Kasai ◽  
S Kawai ◽  
M Kawanishi ◽  
S Yahagi
Keyword(s):  
Evoked Potentials ◽  
Motor Imagery ◽  
Motor Evoked Potentials
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