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Charles Capaday - One of the best experts on this subject based on the ideXlab platform.
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Differential Control of Reciprocal Inhibition During Walking Versus Postural and Voluntary Motor Tasks in Humans
Journal of Neurophysiology, 1997Co-Authors: Brigitte A. Lavoie, Hervé Devanne, Charles CapadayAbstract:Lavoie, Brigitte A., Herve Devanne, and Charles Capaday. Differential control of Reciprocal Inhibition during walking versus postural and voluntary motor tasks in humans. J. Neurophysiol. 78: 429–4...
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differential control of Reciprocal Inhibition during walking versus postural and voluntary motor tasks in humans
Journal of Neurophysiology, 1997Co-Authors: Brigitte Lavoie, Hervé Devanne, Charles CapadayAbstract:Experiments were done to determine whether the strength of Reciprocal Inhibition from ankle flexors to extensors can be controlled independently of the level of ongoing motor activity in a task-dependent manner. In this paper we use the term Reciprocal Inhibition in the functional sense--Inhibition of the antagonist(s) during activity of the agonist(s)--without reference to specific neural pathways that may be involved. The strength of Reciprocal Inhibition of the soleus alpha-motoneurons was determined by measuring the amplitude of the H reflex during voluntary, postural, and locomotor tasks requiring activity of the ankle flexor tibialis anterior (TA). Differences in the strength of Reciprocal Inhibition between tasks were determined from plots of the soleus H reflex amplitude versus the mean value of the TA electromyogram (EMG). Additionally, in tasks involving movement, the correlation between the H reflex amplitude and the joint kinematics was calculated. In most subjects (15 of 22) the soleus H reflex decreased approximately linearly with increasing tonic voluntary contractions of the TA. The H reflex also decreased approximately linearly with the TA EMG activity when subjects where asked to lean backward. There were no statistical differences between the regression lines obtained in these tasks. In some subjects (7 of 22), however, the H reflex amplitude was independent of the level of TA EMG activity, except for a sudden drop at high levels of TA activity (approximately 60-80% of maximum voluntary contraction). The type of relation between the soleus H reflex and the TA EMG activity in these tasks was not correlated with the maximum H reflex to maximum M wave (Hmax/Mmax) ratio measured during quiet standing. In marked contrast, during the swing phase of walking--over the same range of TA EMG activity as during the tonic voluntary contraction task--the H reflex was reduced to zero in most subjects (24 of 31). In seven subjects the H reflex during the swing phase was reduced to some 5% of the value during quiet standing. The same result was found when subjects were asked to produce a stepping movement with one leg (OLS) in response to an auditory "go" signal. Additionally, in the OLS task it was possible to examine the behavior of the H reflex during the reaction time and thus to evaluate the relative contribution of central commands versus movement-related afferent activity to the Inhibition of the soleus H reflex. In 11 of 12 subjects the H reflex attained its minimum value before either the onset of EMG activity or movement of any of the leg joints. It is significant that the H reflex was most powerfully inhibited during the swing phase of walking and the closely related OLS task. The H reflex was also measured during isolated ankle dorsiflexion movements. The subjects were asked to track a target displayed on a computer screen with dorsiflexion movements of the ankle. The trajectory of the target was the same as that of the ankle during the swing phase of walking. The soleus H reflexes were intermediate in size between the values obtained in the tonic contraction task and the walking or OLS tasks. A negative, but weak, correlation (r2 < 0.68) between the soleus H reflex and the TA EMG was found in 3 of 10 subjects. Furthermore, there was no correlation between the H reflex amplitude and the ankle angular displacement or angular velocity. In this task, as in the OLS task, the H reflex began to decrease during the reaction time before the onset of TA EMG activity. We conclude that the strength of Reciprocal Inhibition of the soleus alpha-motoneuron pool can thus be controlled independently of the level of motor activity in the ankle flexors. The strength of the Inhibition of the antagonist(s) depends on the task, and for each task the strength of the Inhibition is not necessarily proportional to the level of motor activity in the agonist(s). (ABSTRACT TRUNCATED)
Jens Nielsen - One of the best experts on this subject based on the ideXlab platform.
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increased central facilitation of antagonist Reciprocal Inhibition at the onset of dorsiflexion following explosive strength training
Journal of Applied Physiology, 2008Co-Authors: Svend Sparre Geertsen, Jesper Lundbyejensen, Jens NielsenAbstract:At the onset of dorsiflexion disynaptic Reciprocal Inhibition (DRI) of soleus motoneurons is increased to prevent activation of the antagonistic plantar flexors. This is caused by descending facili...
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Reduced Reciprocal Inhibition is seen only in spastic limbs in patients with neurolathyrism.
Experimental brain research, 2007Co-Authors: C Crone, Nicolas T. Petersen, S. Gimenez-roldan, Bjarke K. S. Lungholt, K. Nyborg, Jens NielsenAbstract:If reduced Reciprocal Inhibition plays a causal role in the pathophysiology of spasticity as has been suggested in several studies, the Inhibition is expected to be impaired in spastic, but not in normal muscles. Patients with neurolathyrism offer a possibility of testing this prediction since the spastic symptoms in these patients are restricted to the lower extremities only. Three patients with neurolathyrism were tested. Their data were compared with 15 age-matched healthy subjects. All patients showed signs of spasticity in the legs. Two patients had normal voluntary muscle force in the lower extremities and one had decreased force. No clinical abnormalities were found in the upper extremities. Reciprocal Inhibition between ankle dorsiflexor and plantarflexor muscles was absent in all patients, whereas the Inhibition between wrist extensor and flexor muscles was present and of normal size and latency. These findings are consistent with the hypothesis that reduced Reciprocal Inhibition plays a causal role in the pathophysiology of spasticity.
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Changes in Reciprocal Inhibition Across the Ankle Joint With Changes in External Load and Pedaling Rate During Bicycling
Journal of neurophysiology, 2003Co-Authors: Henrik S. Pyndt, Morten Laursen, Jens NielsenAbstract:The purpose of this study was to investigate the role of Reciprocal Inhibition in the regulation of antagonistic ankle muscles during bicycling. A total of 20 subjects participated in the study. Re...
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Patients with the major and minor form of hyperekplexia differ with regards to disynaptic Reciprocal Inhibition between ankle flexor and extensor muscles.
Experimental brain research, 2001Co-Authors: C Crone, Jens Nielsen, Nicolas T. Petersen, Marina A.j. Tijssen, J.g. Van DijkAbstract:The aim of the present study was to investigate the contribution of Reciprocal Inhibition to muscle tone by examining the transmission in the Reciprocal inhibitory pathway in patients with a known defect in the glycine receptor. The study was performed in eight patients with hereditary hyperekplexia, six with the major form and two with the minor form of the disease. A mutation in the alpha1-subunit of the glycine receptor had been demonstrated in the patients with the major form, whereas no mutation was seen in the patients with the minor form. Disynaptic Reciprocal Inhibition, which is presumed to be mediated by glycine, was not seen in the patients with the major form of the disease, while it could be evoked in the patients with the minor form of the disease. Presynaptic Inhibition, which is presumed to be mediated by GABA, was seen in both types of patients. It is concluded that the major form of hereditary hyperekplexia is associated with impaired transmission in glycinergic Reciprocal inhibitory pathways. The findings demonstrate the importance of Reciprocal Inhibition for the muscle tone in man, and it is suggested that the impaired Reciprocal Inhibition seen in patients with a defect in the glycine receptor may contribute to the increased muscle stiffness that is observed in these patients.
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Reciprocal Inhibition in hemiplegic patients--a longitudinal study.
Supplements to Clinical neurophysiology, 2000Co-Authors: C Crone, L L Johnsen, Jens NielsenAbstract:Publisher Summary This chapter discusses an experiment in which the amount of Reciprocal Inhibition between ankle flexors and extensors as well as signs of spasticity were evaluated repeatedly from the onset of disease and until manifest spasticity had developed. In the experiment, five patients had suffered a cerebral infarction and one patient had a cerebral hemorrhage. All patients had leg hemiparesis when they entered the study. Patients entered the study within five days to five weeks after the onset of disease—that is, as soon as their general condition allowed, while one patient was included in the study after he had reached a more chronic stage. The lack of Reciprocal Inhibition, which has been observed in spastic hemiplegic patients in this chapter, is in accordance with previous studies on spastic patients with multiple sclerosis. The facilitation generally had a higher threshold than the D1 Inhibition, which is mediated by Ia afferents. This suggests that it may be caused by disynaptic Ib facilitation. It has been suggested that decreased presynaptic Inhibition of Ia afferents may be involved in the pathophysiology of spasticity. However, in the present study the D1 Inhibition of the soleus H-reflex, which is assumed to be caused by presynaptic Inhibition of soleus Ia afferents, was found to be normal in both the affected and unaffected leg of the hemiplegic patients.
Hervé Devanne - One of the best experts on this subject based on the ideXlab platform.
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Differential Control of Reciprocal Inhibition During Walking Versus Postural and Voluntary Motor Tasks in Humans
Journal of Neurophysiology, 1997Co-Authors: Brigitte A. Lavoie, Hervé Devanne, Charles CapadayAbstract:Lavoie, Brigitte A., Herve Devanne, and Charles Capaday. Differential control of Reciprocal Inhibition during walking versus postural and voluntary motor tasks in humans. J. Neurophysiol. 78: 429–4...
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differential control of Reciprocal Inhibition during walking versus postural and voluntary motor tasks in humans
Journal of Neurophysiology, 1997Co-Authors: Brigitte Lavoie, Hervé Devanne, Charles CapadayAbstract:Experiments were done to determine whether the strength of Reciprocal Inhibition from ankle flexors to extensors can be controlled independently of the level of ongoing motor activity in a task-dependent manner. In this paper we use the term Reciprocal Inhibition in the functional sense--Inhibition of the antagonist(s) during activity of the agonist(s)--without reference to specific neural pathways that may be involved. The strength of Reciprocal Inhibition of the soleus alpha-motoneurons was determined by measuring the amplitude of the H reflex during voluntary, postural, and locomotor tasks requiring activity of the ankle flexor tibialis anterior (TA). Differences in the strength of Reciprocal Inhibition between tasks were determined from plots of the soleus H reflex amplitude versus the mean value of the TA electromyogram (EMG). Additionally, in tasks involving movement, the correlation between the H reflex amplitude and the joint kinematics was calculated. In most subjects (15 of 22) the soleus H reflex decreased approximately linearly with increasing tonic voluntary contractions of the TA. The H reflex also decreased approximately linearly with the TA EMG activity when subjects where asked to lean backward. There were no statistical differences between the regression lines obtained in these tasks. In some subjects (7 of 22), however, the H reflex amplitude was independent of the level of TA EMG activity, except for a sudden drop at high levels of TA activity (approximately 60-80% of maximum voluntary contraction). The type of relation between the soleus H reflex and the TA EMG activity in these tasks was not correlated with the maximum H reflex to maximum M wave (Hmax/Mmax) ratio measured during quiet standing. In marked contrast, during the swing phase of walking--over the same range of TA EMG activity as during the tonic voluntary contraction task--the H reflex was reduced to zero in most subjects (24 of 31). In seven subjects the H reflex during the swing phase was reduced to some 5% of the value during quiet standing. The same result was found when subjects were asked to produce a stepping movement with one leg (OLS) in response to an auditory "go" signal. Additionally, in the OLS task it was possible to examine the behavior of the H reflex during the reaction time and thus to evaluate the relative contribution of central commands versus movement-related afferent activity to the Inhibition of the soleus H reflex. In 11 of 12 subjects the H reflex attained its minimum value before either the onset of EMG activity or movement of any of the leg joints. It is significant that the H reflex was most powerfully inhibited during the swing phase of walking and the closely related OLS task. The H reflex was also measured during isolated ankle dorsiflexion movements. The subjects were asked to track a target displayed on a computer screen with dorsiflexion movements of the ankle. The trajectory of the target was the same as that of the ankle during the swing phase of walking. The soleus H reflexes were intermediate in size between the values obtained in the tonic contraction task and the walking or OLS tasks. A negative, but weak, correlation (r2 < 0.68) between the soleus H reflex and the TA EMG was found in 3 of 10 subjects. Furthermore, there was no correlation between the H reflex amplitude and the ankle angular displacement or angular velocity. In this task, as in the OLS task, the H reflex began to decrease during the reaction time before the onset of TA EMG activity. We conclude that the strength of Reciprocal Inhibition of the soleus alpha-motoneuron pool can thus be controlled independently of the level of motor activity in the ankle flexors. The strength of the Inhibition of the antagonist(s) depends on the task, and for each task the strength of the Inhibition is not necessarily proportional to the level of motor activity in the agonist(s). (ABSTRACT TRUNCATED)
Meigen Liu - One of the best experts on this subject based on the ideXlab platform.
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Effects of Leg Motor Imagery Combined With Electrical Stimulation on Plasticity of Corticospinal Excitability and Spinal Reciprocal Inhibition.
Frontiers in neuroscience, 2019Co-Authors: Yoko Takahashi, Tomofumi Yamaguchi, Michiyuki Kawakami, Shigeo Tanabe, Yusuke Idogawa, Kunitsugu Kondo, Meigen LiuAbstract:Motor imagery (MI) combined with electrical stimulation (ES) enhances upper-limb corticospinal excitability. However, its after-effects on both lower limb corticospinal excitability and spinal Reciprocal Inhibition remain unknown. We aimed to investigate the effects of MI combined with peripheral nerve ES (MI + ES) on the plasticity of lower limb corticospinal excitability and spinal Reciprocal Inhibition. Seventeen healthy individuals performed the following three tasks on different days, in a random order: (1) MI alone; (2) ES alone; and (3) MI + ES. The MI task consisted of repetitive right ankle dorsiflexion for 20 min. ES was percutaneously applied to the common peroneal nerve at a frequency of 100 Hz and intensity of 120% of the sensory threshold of the tibialis anterior (TA) muscle. We examined changes in motor-evoked potential (MEP) of the TA (task-related muscle) and soleus muscle (SOL; task-unrelated muscle). We also examined disynaptic Reciprocal Inhibition before, immediately after, and 10, 20, and 30 min after the task. MI + ES significantly increased TA MEPs immediately and 10 min after the task compared with baseline, but did not change the task-unrelated muscle (SOL) MEPs. MI + ES resulted in a significant increase in the magnitude of Reciprocal Inhibition immediately and 10 min after the task compared with baseline. MI and ES alone did not affect TA MEPs or Reciprocal Inhibition. MI combined with ES is effective in inducing plastic changes in lower limb corticospinal excitability and Reciprocal Ia Inhibition.
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voluntary contraction enhances spinal Reciprocal Inhibition induced by patterned electrical stimulation in patients with stroke
Restorative Neurology and Neuroscience, 2018Co-Authors: Yoko Takahashi, Toshiyuki Fujiwara, Tomofumi Yamaguchi, Michiyuki Kawakami, Katsuhiro Mizuno, Kaoru Honaga, Hikaru Matsunaga, Meigen LiuAbstract:Background Reciprocal Inhibition (RI) may be important for recovering locomotion after stroke. Patterned electrical stimulation (PES) can modulate RI in a manner that could be enhanced by voluntary muscle contraction (VC). Objective To investigate whether VC enhances the PES-induced spinal RI in patients with stroke. Methods Twelve patients with chronic stroke underwent three 20 min tasks, each on different days: (1) PES (10 pulses, 100 Hz every 2 s) applied to the common peroneal nerve; (2) VC consisting of isometric contraction of the affected-side tibialis anterior muscle; (3) PES combined with VC (PES + VC). RI from the tibialis anterior to the soleus muscle was assessed before, immediately after, and 10, 20, and 30 min after the task. Results Compared to the baseline, PES + VC significantly increased the changes in Reciprocal Inhibition at immediately after and 10 min after the task. PES alone significantly increased this change immediately after the task, while VC alone showed no significant increase. Conclusion VC enhanced the PES-induced plastic changes in RI in patients with stroke. This effect can potentially increase the success rate of newer neurorehabilitative approaches in achieving functional recovery after stroke.
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The effects of patterned electrical stimulation combined with voluntary contraction on spinal Reciprocal Inhibition in healthy individuals.
Neuroreport, 2017Co-Authors: Yoko Takahashi, Toshiyuki Fujiwara, Tomofumi Yamaguchi, Michiyuki Kawakami, Katsuhiro Mizuno, Meigen LiuAbstract:The aim of this study was to examine the effects of voluntary contraction (VC) on the modulation of Reciprocal Inhibition induced by patterned electrical stimulation (PES) in healthy individuals. Twelve healthy volunteers participated in this study. PES was applied to the common peroneal nerve with a train of 10 pulses at 100 Hz every 2 s for 20 min. VC comprised repetitive ankle dorsiflexion at a frequency of 0.5 Hz for 20 min. All participants performed the following three tasks: (i) VC alone, (ii) PES alone, and (iii) PES combined with VC (PES+VC). Reciprocal Inhibition was assessed using a soleus H-reflex conditioning-test paradigm at the time points of before, immediately after, 10 min after, 20 min after, and 30 min after the tasks. PES+VC increased the amount of Reciprocal Inhibition, with after-effects lasting up to 20 min. PES alone increased Reciprocal Inhibition and maintained the after-effects on Reciprocal Inhibition for 10 min, whereas VC alone increased only immediately after the task. VC could modulate the plastic changes in spinal Reciprocal Inhibition induced by PES in healthy individuals. PES combined with VC has a potential to modulate impaired Reciprocal Inhibition and it may facilitate functional recovery and improve locomotion after central nervous system lesions.
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After-effects of pedaling exercise on spinal excitability and spinal Reciprocal Inhibition in patients with chronic stroke
The International journal of neuroscience, 2016Co-Authors: Akira Tanuma, Toshiyuki Fujiwara, Tomofumi Yamaguchi, Hirotaka Arano, Shintaro Uehara, Kaoru Honaga, Masahiko Mukaino, Akio Kimura, Meigen LiuAbstract:Purpose of the study: To evaluate the after-effects of pedaling on spinal excitability and spinal Reciprocal Inhibition in patients with post-stroke spastic hemiparesis. Materials and methods: Twenty stroke patients with severe hemiparesis participated in this study and were instructed to perform 7 min of active pedaling and 7 min of passive pedaling with a recumbent ergometer at a comfortable speed. H reflexes and M waves of paretic soleus muscles were recorded at rest before, immediately after and 30 min after active and passive pedaling. The Hmax/Mmax ratio and H recruitment curve were measured. Reciprocal Inhibition was assessed using the soleus H reflex conditioning test paradigm. Results: The Hmax/Mmax ratio was significantly decreased after active and passive pedaling exercise. The decreased Hmax/Mmax ratio after active pedaling lasted at least for 30 min. The H recruitment curve and Reciprocal Inhibition did not change significantly after active or passive pedaling exercise. Conclusions: Pedaling ...
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The effect of active pedaling combined with electrical stimulation on spinal Reciprocal Inhibition.
Journal of electromyography and kinesiology : official journal of the International Society of Electrophysiological Kinesiology, 2012Co-Authors: Tomofumi Yamaguchi, Toshiyuki Fujiwara, Kei Saito, Shigeo Tanabe, Yoshihiro Muraoka, Yohei Otaka, Rieko Osu, Tetsuya Tsuji, Kimitaka Hase, Meigen LiuAbstract:Abstract Objective Pedaling is widely used for rehabilitation of locomotion because it induces muscle activity very similar to locomotion. Afferent stimulation is important for the modulation of spinal reflexes. Furthermore, supraspinal modulation plays an important role in spinal plasticity induced by electrical stimulation. We, therefore, expected that active pedaling combined with electrical stimulation could induce strong after-effects on spinal reflexes. Design Twelve healthy adults participated in this study. They were instructed to perform 7 min of pedaling. We applied electrical stimulation to the common peroneal nerve during the extension phase of the pedaling cycle. We assessed Reciprocal Inhibition using a soleus H-reflex conditioning-test paradigm. The magnitude of Reciprocal Inhibition was measured before, immediately after, 15 and 30 min after active pedaling alone, electrical stimulation alone and active pedaling combined with electrical stimulation (pedaling + ES). Results The amount of Reciprocal Inhibition was significantly increased after pedaling + ES. The after-effect of pedaling + ES on Reciprocal Inhibition was more prominent and longer lasting compared with pedaling or electrical stimulation alone. Conclusions Pedaling + ES could induce stronger after-effects on spinal Reciprocal inhibitory neurons compared with either intervention alone. Pedaling + ES might be used as a tool to improve locomotion and functional abnormalities in the patient with central nervous lesion.
Brigitte A. Lavoie - One of the best experts on this subject based on the ideXlab platform.
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Differential Control of Reciprocal Inhibition During Walking Versus Postural and Voluntary Motor Tasks in Humans
Journal of Neurophysiology, 1997Co-Authors: Brigitte A. Lavoie, Hervé Devanne, Charles CapadayAbstract:Lavoie, Brigitte A., Herve Devanne, and Charles Capaday. Differential control of Reciprocal Inhibition during walking versus postural and voluntary motor tasks in humans. J. Neurophysiol. 78: 429–4...
