Electroencephalography and Clinical Neurophysiology/Electromyography and Motor Control最新文献_第9页

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Electroencephalography and Clinical Neurophysiology/Electromyography and Motor Control Pub Date : 1997-12-01 DOI: 10.1016/S0924-980X(97)00067-2

引用次数: 0

Index 指数

Electroencephalography and Clinical Neurophysiology/Electromyography and Motor Control Pub Date : 1997-12-01 DOI: 10.1016/S0924-980X(97)00069-6

引用次数: 0

Diverse abnormalities of corticomotoneuronal projections in individual patients with amyotrophic lateral sclerosis 肌萎缩性侧索硬化症患者皮质神经元投射的多种异常

Electroencephalography and Clinical Neurophysiology/Electromyography and Motor Control Pub Date : 1997-12-01 DOI: 10.1016/S0924-980X(97)00051-9

Masashi Nakajima , Andrew Eisen , Heather Stewart

{"title":"Diverse abnormalities of corticomotoneuronal projections in individual patients with amyotrophic lateral sclerosis","authors":"Masashi Nakajima , Andrew Eisen , Heather Stewart","doi":"10.1016/S0924-980X(97)00051-9","DOIUrl":"10.1016/S0924-980X(97)00051-9","url":null,"abstract":"<div><p><span><span>Using peristimulus time histograms (PSTHs), abnormalities of composite </span>excitatory postsynaptic potentials<span> (EPSPs) induced by transcranial magnetic stimulation<span><span> were studied in multiple motor units from individuals with </span>amyotrophic lateral sclerosis (ALS) and normal subjects. We studied 97 motor units in the extensor </span></span></span>digitorum<span> communis muscle of 22 patients with sporadic ALS and 47 motor units of 10 healthy control subjects. Four or five motor units were studied in each patient and normal subject. For each unit, macro motor unit potentials (Macro-MUPs) were simultaneously recorded from a surface electrode after spike-triggered averaging. The composite EPSPs in ALS showed a generally bi-directional deviation from the normal curve, with small EPSPs at one end, and larger amplitude EPSPs with a prolonged rise time at the other end. The variability of EPSPs from adjacent motor units in the same individual was significantly larger in ALS than in controls. In normal subjects there is a significant negative correlation between the amplitude of composite EPSPs and the Macro-MUPs. In ALS, the trend is reversed (positive) suggesting that the abnormalities of composite EPSPs are supraspinal in origin. A combination of partial attrition of the corticomotoneuronal core and hyper-excitability of surviving corticomotoneurons projecting to a given spinal motoneuron pool best explains the diversity of the composite EPSP in individuals with ALS.</span></p></div>","PeriodicalId":100400,"journal":{"name":"Electroencephalography and Clinical Neurophysiology/Electromyography and Motor Control","volume":"105 6","pages":"Pages 451-457"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0924-980X(97)00051-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20375333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 25

Gait analysis during treadmill and overground locomotion in children and adults 儿童和成人在跑步机和地上运动时的步态分析

Electroencephalography and Clinical Neurophysiology/Electromyography and Motor Control Pub Date : 1997-12-01 DOI: 10.1016/S0924-980X(97)00055-6

H Stolze , J.P Kuhtz-Buschbeck , C Mondwurf , A Boczek-Funcke , K Jöhnk , G Deuschl , M Illert

{"title":"Gait analysis during treadmill and overground locomotion in children and adults","authors":"H Stolze , J.P Kuhtz-Buschbeck , C Mondwurf , A Boczek-Funcke , K Jöhnk , G Deuschl , M Illert","doi":"10.1016/S0924-980X(97)00055-6","DOIUrl":"10.1016/S0924-980X(97)00055-6","url":null,"abstract":"<div><p>Gait analysis<span> on the treadmill and in the overground condition is used both in scientific approaches for investigating the neuronal organisation and ontogenetic development of locomotion and in a variety of clinical applications. We investigated the differences between overground and treadmill locomotion (at identical gait velocity) in 12 adults and 14 children (6–7 years old). During treadmill locomotion the step frequency increased by 7% in adults and 10% in children compared to overground walking, whereas the stride length and the stance phase of the walking cycle decreased. The swing phase, however, increased significantly by 5% in adults and remained unchanged in children. Balance-related gait parameters such as the step width and foot rotation angles increased during treadmill locomotion. The reduction of the step length was found to be stable after 10 min of treadmill walking in most subjects. With regard to the shifted phases of the walking cycle and the changed balance related gait parameters in the treadmill condition, we assume a different modulation of the central pattern generator in treadmill walking, due to a changed afferent input. Regarding the pronounced differences between overground and treadmill walking in children, it is discussed whether the systems generating and integrating different modulations of locomotion into a stable movement pattern have reached full capacity in 6–7 year old children.</span></p></div>","PeriodicalId":100400,"journal":{"name":"Electroencephalography and Clinical Neurophysiology/Electromyography and Motor Control","volume":"105 6","pages":"Pages 490-497"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0924-980X(97)00055-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20377780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 273

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Electroencephalography and Clinical Neurophysiology/Electromyography and Motor Control Pub Date : 1997-12-01 DOI: 10.1016/S0924-980X(97)00068-4

引用次数: 0

Transcranial magnetic double stimulation: influence of the intensity of the conditioning stimulus 经颅磁双刺激:条件刺激强度的影响

Electroencephalography and Clinical Neurophysiology/Electromyography and Motor Control Pub Date : 1997-12-01 DOI: 10.1016/S0924-980X(97)00054-4

M Schäfer , J.C Biesecker , A Schulze-Bonhage , A Ferbert

{"title":"Transcranial magnetic double stimulation: influence of the intensity of the conditioning stimulus","authors":"M Schäfer , J.C Biesecker , A Schulze-Bonhage , A Ferbert","doi":"10.1016/S0924-980X(97)00054-4","DOIUrl":"10.1016/S0924-980X(97)00054-4","url":null,"abstract":"<div><p><span><span>The influence of stimulus parameters on compound muscle potentials evoked by transcranial magnetic double stimulation was systematically investigated. Two magnetic stimulators were discharged via a figure-of-eight-shaped magnetic coil (outer diameter of each circular coil, 7 cm) over the left hemisphere, 6 cm lateral to Cz, using a Bistim interface. Recordings were made from the right first dorsal interosseus muscle. In experiment I, in 12 healthy volunteers the intensity of the conditioning subthreshold stimulus was varied from 0 to 100% of the relaxed motor threshold at an interstimulus interval of 1 ms. In experiment II, interstimulus intervals of 1, 3 and 5 ms were used to investigate the effect of conditioning stimuli of 3 fixed intensities. Maximal reduction of the amplitude of </span>motor evoked potentials was found at a conditioning stimulus intensity of 65% of the relaxed motor threshold (and at an interstimulus interval of 1 ms). Because intensities of the conditioning stimulus higher than 65% reduced amplitudes of motor evoked potentials less effectively than at this intensity, refractoriness of pyramidal neurons can be ruled out as the main mechanism contributing to the observed inhibition. Activation of inhibitory interneurons by intensities lower than is necessary to activate pyramidal neurons is discussed as a possible mechanism for the inhibitory effects evoked by </span>transcranial magnetic stimulation.</p></div>","PeriodicalId":100400,"journal":{"name":"Electroencephalography and Clinical Neurophysiology/Electromyography and Motor Control","volume":"105 6","pages":"Pages 462-469"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0924-980X(97)00054-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20375335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 47

H-reflexes of different sizes exhibit differential sensitivity to low frequency depression 不同大小的h反射对低频抑制表现出不同的敏感性

Electroencephalography and Clinical Neurophysiology/Electromyography and Motor Control Pub Date : 1997-12-01 DOI: 10.1016/S0924-980X(97)00032-5

M K. Floeter, A F. Kohn

{"title":"H-reflexes of different sizes exhibit differential sensitivity to low frequency depression","authors":"M K. Floeter, A F. Kohn","doi":"10.1016/S0924-980X(97)00032-5","DOIUrl":"10.1016/S0924-980X(97)00032-5","url":null,"abstract":"<div><p>The amplitude of the H-reflex declines when activated repetitively. The magnitude of decline is greater when the amplitude of the H-reflex is small. To explore whether pre- or postsynaptic factors contribute to the differences observed in H-reflexes of different sizes, changes in the amplitude of H-reflexes of different sizes were measured during a train of stimulation in 10 normal subjects. Amplitudes of different sizes were obtained using differing stimulus intensities or during superimposed contraction, two manipulations which differently affect the number of active afferents and the excitation of the motoneuron pool. Small amplitude H-reflexes depressed to a lower plateau than larger H-reflexes and superimposed contraction did not alleviate the depression during each train. Nearly all the decline in larger amplitude H-reflexes occurred in a component that was in common with smaller amplitude H-reflexes. This suggests that the depressibility of the earliest activated units is greater than later activated units in H-reflexes and that the magnitude of decline is affected by prior activity as well as size.</p></div>","PeriodicalId":100400,"journal":{"name":"Electroencephalography and Clinical Neurophysiology/Electromyography and Motor Control","volume":"105 6","pages":"Pages 470-475"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0924-980X(97)00032-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20375336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 52

Post-stroke reorganization of brain motor output to the hand: a 2–4 month follow-up with focal magnetic transcranial stimulation 脑卒中后手部运动输出的重组:局部经颅磁刺激2-4个月随访

Electroencephalography and Clinical Neurophysiology/Electromyography and Motor Control Pub Date : 1997-12-01 DOI: 10.1016/S0924-980X(97)00052-0

P Cicinelli , R Traversa , P.M Rossini

{"title":"Post-stroke reorganization of brain motor output to the hand: a 2–4 month follow-up with focal magnetic transcranial stimulation","authors":"P Cicinelli , R Traversa , P.M Rossini","doi":"10.1016/S0924-980X(97)00052-0","DOIUrl":"10.1016/S0924-980X(97)00052-0","url":null,"abstract":"<div><p><span><span>Focal transcranial magnetic stimulation (TCS) was employed for the representation of the motor cortex in a population of 18 patients to investigate the functional properties of hand motor areas 2–4 months after a monohemispheric stroke. Eleven sites were stimulated to elicit motor evoked potentials (MEPs) in abductor digiti minimi muscle after TCS of affected (AH) and unaffected (UH) hemispheres; recording sessions were performed at the beginning (T1) and after 8–10 weeks (T2) of </span>neurorehabilitation<span>. Barthel index and Canadian neurological scale scores were evaluated. A group of 20 healthy control subjects was enrolled. In stroke patients the AH was less excitable than normal, combined with a decrease in motor cortical output area (</span></span><em>P</em><0.05) in T1. In T2, there was an enlargement of the hand motor area on the AH combined with an improvement of clinical scores (<em>P</em><0.001). In T1 and T2, the amplitude of MEPs in the AH was reduced (<em>P</em><0.001) with a prolongation of central conduction time (<em>P</em><0.001) and with a tendency towards improvement in T2; the amplitude of contracted MEPs was larger than normal in the UH in T1. Both in T1 and T2, anomalous `hot spot' (most excitable) scalp sites, never seen in normals, were often encountered (T2>T1) on the AH and UH. Interhemispheric differences for topography and latency of MEPs were remarkably affected. Our data are consistent with a rearrangement of the brain motor cortical output between 2 and 4 months following stroke. The amelioration of the neurophysiological parameters was correlated with clinical improvement in disability and neurological scores. This study confirms the existence in adults of brain `plasticity' still operating between 2 and 4 months from an acute vascular monohemispheric insult.</p></div>","PeriodicalId":100400,"journal":{"name":"Electroencephalography and Clinical Neurophysiology/Electromyography and Motor Control","volume":"105 6","pages":"Pages 438-450"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0924-980X(97)00052-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20375332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 272

Central motor conduction time by magnetic stimulation of the cortex and peripheral nerve conduction follow-up studies in Friedreich's ataxia 磁刺激皮层的中枢运动传导时间和周围神经传导对弗里德赖希共济失调的随访研究

Electroencephalography and Clinical Neurophysiology/Electromyography and Motor Control Pub Date : 1997-12-01 DOI: 10.1016/S0924-980X(97)00047-7

A Cruz-Martı́nez , F Palau

引用次数: 24

Leg muscle activation during gait in Parkinson's disease: influence of body unloading 帕金森病步态中的腿部肌肉激活:身体卸载的影响

Electroencephalography and Clinical Neurophysiology/Electromyography and Motor Control Pub Date : 1997-10-01 DOI: 10.1016/S0924-980X(97)00042-8

V. Dietz , K.L. Leenders , G. Colombo

{"title":"Leg muscle activation during gait in Parkinson's disease: influence of body unloading","authors":"V. Dietz , K.L. Leenders , G. Colombo","doi":"10.1016/S0924-980X(97)00042-8","DOIUrl":"10.1016/S0924-980X(97)00042-8","url":null,"abstract":"<div><p>The effect of body unloading (75, 50 and 25% of body weight) on upper and lower leg muscle activation during stepping on a treadmill was investigated in groups of patients with Parkinson's disease and age-matched healthy subjects. The aim of the study was to test the hypothesis that impaired extensor load receptor function exists in the patients. A strong load sensitivity was found for the gastrocnemius (GM) electromyographic (EMG) activity (i.e. EMG amplitude decreased with unloading during stepping in both groups of subjects). The change in the EMG amplitude of the rectus femoris was less dependent upon the load but was observed to be more pronounced in the patients. Upper and lower leg flexor muscles were relatively load-insensitive. The absolute GM EMG amplitude during the stance phase of stepping with normal body loading was significantly smaller in the patients than in the healthy subjects. It is suggested that the latter observation is due to a change in the threshold or bias of the extensor load reflex mechanism in the patients. The slope or gain of this reflex appears to be preserved.</p></div>","PeriodicalId":100400,"journal":{"name":"Electroencephalography and Clinical Neurophysiology/Electromyography and Motor Control","volume":"105 5","pages":"Pages 400-405"},"PeriodicalIF":0.0,"publicationDate":"1997-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0924-980X(97)00042-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20295268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 45