共查询到20条相似文献，搜索用时 31 毫秒
1.
José Manuel Matamala James Howells Thanuja Dharmadasa William Huynh Susanna B. Park David Burke Matthew C. Kiernan 《Clinical neurophysiology》2018,129(7):1472-1478
Objective
To evaluate the excitability of sensory axons in patients with amyotrophic lateral sclerosis (ALS).Methods
Comprehensive sensory nerve excitability studies were prospectively performed on 28 sporadic ALS patients, compared to age-matched controls. Sensory nerve action potentials were recorded from digit 2 following median nerve stimulation at the wrist. Disease severity was measured using motor unit number estimation (MUNE), the revised ALS Functional Rating Scale (ALSFRS-R) and the MRC scale.Results
There were no significant differences in standard and extended measures of nerve excitability between ALS patients and controls. These unchanged excitability measures included accommodation to long-lasting hyperpolarization and the threshold changes after two supramaximal stimuli during the recovery cycle. Excitability parameters did not correlate with MUNE, ALSFRS-R, APB MRC scale or disease duration.Conclusions
This cross-sectional study has identified normal axonal membrane properties in myelinated sensory axons of ALS patients. Previously described sensory abnormalities could be the result of axonal fallout, possibly due to a ganglionopathy, or to involvement of central sensory pathways rostral to gracile and cuneate nuclei.Significance
These results demonstrate the absence of generalized dysfunction of the membrane properties of sensory axons in ALS in the face of substantial deficits in motor function. 相似文献2.
Yuki Hatanaka Mana Higashihara Takashi Chiba Yosuke Miyaji Yasuomi Kawamura Masahiro Sonoo 《Clinical neurophysiology》2017,128(5):823-829
Objective
Decremental responses in the repetitive nerve stimulation (RNS) test in amyotrophic lateral sclerosis (ALS) patients have been reported, although their possible diagnostic role has received little investigation. We investigated their diagnostic role in differentiation between ALS and cervical spondylotic amyotrophy (CSA), an important ALS mimic especially in Japan.Methods
Patients were prospectively enrolled and the diagnosis was confirmed by follow-up. RNS was performed on the abductor pollicis brevis (APB), upper trapezius (trapezius) and deltoid muscles.Results
Enrolled subjects consisted of 53 ALS and 37 CSA patients. Abnormal decremental responses (>5%) were observed in 32%, 51% and 75% of ALS patients and 3%, 0% and 20% of CSA patients for the APB, trapezius and deltoid muscles, respectively. The sensitivity for 23 ALS patients with upper-limb onset was 78% for the trapezius and 100% for the deltoid muscles.Conclusions
An abnormal decremental response in the trapezius muscle was 100% specific to ALS in comparison with CSA: abnormal decrement in this muscle would strongly suggest ALS. No decrement in the deltoid muscle might exclude ALS in patients having symptoms with upper-limb onset.Significance
RNS is useful in differentiation between ALS and CSA. 相似文献3.
Antoine Gueguen Claude Jardel Marc Polivka S. Veronica Tan Françoise Gray Catherine Vignal Anne Lombès Olivier Gout Hugh Bostock 《Clinical neurophysiology》2017,128(7):1258-1263
Objective
To explore potential spreading to peripheral nerves of the mitochondrial dysfunction in chronic progressive external ophthalmoplegia (CPEO) by assessing axonal excitability.Methods
CPEO patients (n = 13) with large size deletion of mitochondrial DNA and matching healthy controls (n = 22) were included in a case-control study. Muscle strength was quantified using MRC sum-score and used to define two groups of patients: CPEO-weak and CPEO-normal (normal strength). Nerve excitability properties of median motor axons were assessed with the TROND protocol and changes interpreted with the aid of a model.Results
Alterations of nerve excitability strongly correlated with scores of muscle strength. CPEO-weak displayed abnormal nerve excitability compared to CPEO-normal and healthy controls, with increased superexcitability and responses to hyperpolarizing current. Modeling indicated that the CPEO-weak recordings were best explained by an increase in the ‘Barrett-Barrett’ conductance across the myelin sheath.Conclusion
CPEO patients with skeletal weakness presented sub-clinical nerve excitability changes, which were not consistent with axonal membrane depolarization, but suggested Schwann cell involvement.Significance
This study provides new insights into the spreading of large size deletion of mitochondrial DNA to Schwann cells in CPEO patients. 相似文献4.
Steven Hageman Maria O. Kovalchuk Boudewijn T.H.M. Sleutjes Leonard J. van Schelven Leonard H. van den Berg Hessel Franssen 《Clinical neurophysiology》2018,129(4):809-814
Objective
Sodium-potassium pump dysfunction in peripheral nerve is usually assessed by determining axonal hyperpolarization following maximal voluntary contraction (MVC) or maximal electrical nerve stimulation. As MVC may be unreliable and maximal electrical stimulation too painful, we assessed if hyperpolarization can also be induced by submaximal electrical nerve stimulation.Methods
In 8 healthy volunteers different submaximal electrical stimulus trains were given to the median nerve at the wrist, followed by 5 min assessment of thresholds for compound muscle action potentials of 20%, 40% or 60% of maximal.Results
Threshold increase after submaximal electrical nerve stimulation was most prominent after an 8?Hz train of at least 5 min duration evoking submaximal CMAPs of 60%. It induced minimal discomfort and was not painful. Threshold increase after MVC was not significantly higher than this stimulus train.Conclusions
Submaximal electrical stimulation evokes activity dependent hyperpolarization in healthy test subjects without causing significant discomfort.Significance
Sodium-potassium pump function may be assessed using submaximal electrical stimulation. 相似文献5.
Gian Maria Fabrizi Stefano Tamburin Tiziana Cavallaro Ilaria Cabrini Moreno Ferrarini Federica Taioli Francesca Magrinelli Giampietro Zanette 《Clinical neurophysiology》2018,129(1):21-32
Objective
Nerve ultrasound (US) data on myelin protein zero (MPZ)-related Charcot-Marie-Tooth disease (CMT) are lacking. To offer a comprehensive perspective on MPZ-related CMTs, we combined nerve US with clinics, electrodiagnosis and histopathology.Methods
We recruited 36 patients (12 MPZ mutations), and correlated nerve US to clinical, electrodiagnostic measures, and sural nerve biopsy.Results
According to motor nerve conduction velocity (MNCV) criteria, nine patients were categorized as “demyelinating” CMT1B, 17 as “axonal” CMT2I/J, and 10 as dominant “intermediate” CMTDID. Sural nerve biopsy showed hypertrophic de-remyelinating neuropathy with numerous complex onion bulbs in one patient, de-remyelinating neuropathy with scanty/absent onion bulbs in three, axonal neuropathy in two, mixed demyelinating-axonal neuropathy in five. Electrodiagnosis significantly differed in CMT1B vs. CMT2I/J and CMTDID subgroups. CMT1B had slightly enlarged nerve cross sectional area (CSA) especially at proximal upper-limb (UL) sites. CSA was negatively correlated to UL MNCV and not increased at entrapment sites. Major sural nerve pathological patterns were uncorrelated to UL nerve US and MNCV.Conclusions
Sural nerve biopsy confirmed the wide pathological spectrum of MPZ-CMT. UL nerve US identified two major patterns corresponding to the CMT1B and CMT2I/J-CMTDID subgroups.Significance
Nerve US phenotype of MPZ-CMT diverged from those in other demyelinating peripheral neuropathies and may have diagnostic value. 相似文献6.
Rikke Heide Hugh Bostock Lise Ventzel Peter Grafe Joseph Bergmans Anders Fuglsang-Frederiksen Nanna B. Finnerup Hatice Tankisi 《Clinical neurophysiology》2018,129(3):694-706
Objective
Neurotoxicity is the most frequent dose-limiting side effect of the anti-cancer agent oxaliplatin, but the mechanisms are not well understood. This study used nerve excitability testing to investigate the pathophysiology of the acute neurotoxicity.Methods
Questionnaires, quantitative sensory tests, nerve conduction studies and nerve excitability testing were undertaken in 12 patients with high-risk colorectal cancer treated with adjuvant oxaliplatin and in 16 sex- and age-matched healthy controls. Examinations were performed twice for patients: once within 3?days after oxaliplatin treatment (post-infusion examination) and once shortly before the following treatment (recovery examination).Results
The most frequent post-infusion symptoms were tingling paresthesias and cold allodynia. The most prominent nerve excitability change was decreased superexcitability of motor axons which correlated with the average intensity of abnormal sensations (Spearman Rho?=?0.80, p?<?.01). The motor nerve excitability changes were well modeled by a slowing of sodium channel inactivation, and were proportional to dose/m2 with a half-life of about 10d.Conclusions
Oxaliplatin induces reversible slowing of sodium channel inactivation in motor axons, and these changes are closely related to the reversible cold allodynia. However, further studies are required due to small sample size in this study.Significance
Nerve excitability data provide an index of sodium channel dysfunction: an objective biomarker of acute oxaliplatin neurotoxicity. 相似文献7.
Svjetlana Miocinovic Andrew Miller Nicole C. Swann Jill L. Ostrem Philip A. Starr 《Clinical neurophysiology》2018,129(2):368-376
Objective
To investigate cortical activity using scalp EEG in patients with isolated dystonia treated with chronic deep brain stimulation (DBS), on and off stimulation.Methods
We analyzed 64-channel scalp EEG in 12 isolated dystonia patients treated with chronic DBS (7 generalized, 5 cervical/segmental; 7 globus pallidus (GP), 5 subthalamic nucleus (STN)), and 20 healthy age-matched controls. Recordings during rest and movement task, and clinical motor scores, were collected with DBS-on and during a 90-min DBS washout.Results
Resting state alpha power in the dominant (or contralateral to more dystonic side) motor cortex channel during DBS was comparable to healthy controls, but it increased when DBS was stopped. Resting state and movement-related alpha coherence between bilateral motor cortex channels was increased off DBS.Conclusions
Chronic DBS reduces exaggerated alpha oscillations and interhemispheric alpha coherence in the motor cortex of patients with isolated dystonia.Significance
These findings complement related studies in Parkinson’s disease and support the view that network desynchronization is a prominent mechanism of DBS in movement disorders. 相似文献8.
Boudewijn T.H.M. Sleutjes Judith Drenthen Ernest Boskovic Leonard J. van Schelven Maria O. Kovalchuk Paul G.E. Lumens Leonard H. van den Berg Hessel Franssen 《Clinical neurophysiology》2018,129(8):1634-1641
Objective
To study excitability of single motor units (MUs) using high-density surface-EMG.Methods
Motor unit action potentials (MUAPs) were evoked by submaximal stimulation of the median nerve at the wrist and recorded with a 9?×?14 electrode grid on the skin overlying the thenar muscles. For excitability tests of single MUs, the most optimal specific single-channel surface-EMG signal was selected based on the spatiotemporal profile of single MUs.Results
Axonal excitability measures were successfully obtained from 14 single MUs derived from ten healthy subjects. Selecting the optimal single-channel surface-EMG signals minimized interference from other single MUs and improved signal-to-noise ratio. The muscle fiber conduction velocity (MFCV) could also be derived from the unique spatiotemporal profile of single MUs.Conclusion
High-density surface-EMG helps to isolate single MUAP responses, making it a suitable technique for assessing excitability in multiple single motor axons per nerve.Significance
Our method enables the reliable study of ion-channel dysfunction in single motor axons of nerves without any requirement for specific conditions, such as prominent MU loss or enlarged MUAPs due to collateral sprouting. 相似文献9.
Ingrid J.T. Herraets H. Stephan Goedee Johan A. Telleman Jan-Thies H. van Asseldonk Leo H. Visser W. Ludo van der Pol Leonard H. van den Berg 《Clinical neurophysiology》2018,129(1):232-237
Objective
Wartenberg’s migrant sensory neuritis (WMSN) is a rare, patchy, pure sensory neuropathy of unknown etiology. High-resolution ultrasonography (HRUS) is an emerging diagnostic technique for neuropathies, but it has not been applied in WMSN. In this study we aimed to determine HRUS abnormalities in WMSN.Methods
We performed a case-control study of 8 newly diagnosed patients with WMSN and 22 treatment-naive disease controls (16 patients with pure sensory axonal neuropathy and 6 with pure sensory chronic inflammatory demyelinating polyneuropathy (CIDP) or Lewis-Sumner syndrome (LSS)). All patients underwent routine diagnostic evaluations and a predefined HRUS protocol.Results
We found multifocal nerve enlargement in all 8 WMSN patients. The median nerve in the upper arm and the sural nerve were significantly larger in WMSN than in axonal controls (p?=?0.01 and p?=?0.04). In CIDP/LSS, sonographic enlargement was more extensive. Furthermore we found brachial plexus involvement in 3 of 8 (38%) WMSN patients.Conclusion
HRUS showed enlargement of multiple nerves in all WMSN patients even if clinical testing and NCS were normal.Significance
The feature of multifocal nerve enlargement may be of additional value in establishing the diagnosis of WMSN and may support the suggestion of an auto-immune etiology. 相似文献10.
Giampietro Zanette Gian Maria Fabrizi Federica Taioli Matteo Francesco Lauriola Andrea Badari Moreno Ferrarini Tiziana Cavallaro Stefano Tamburin 《Clinical neurophysiology》2018,129(11):2259-2267
Objective
Ulnar/median motor nerve conduction velocity (MNCV) is ≤38?m/s in demyelinating Charcot-Marie-Tooth disease (CMT). Previous nerve high resolution ultrasound (HRUS) studies explored demyelinating CMT assuming it as a homogeneous genetic/pathological entity or focused on CMT1A.Methods
To explore the spectrum of nerve HRUS findings in demyelinating CMTs, we recruited patients with CMT1A (N?=?44), CMT1B (N?=?9), CMTX (N?=?8) and CMT4C (N?=?4). They underwent nerve conduction study (NCS) and HRUS of the median, ulnar, peroneal nerve, and the brachial plexus.Results
Median, ulnar and peroneal MNCV significantly differed across CMT subtypes. Cross sectional area (CSA) was markedly and diffusely enlarged at all sites, except entrapment ones, in CMT1A, while it was slightly enlarged or within normal range in the other CMTs. No significant right-to-left difference was found. Age had limited effect on CSA. CSAs of some CMT1A patients largely overlapped with those of other demyelinating CMTs. A combination of three median CSA measures could separate CMT1A from other demyelinating CMTs.Conclusions
Nerve HRUS findings are heterogeneous in demyelinating CMTs.Significance
Nerve HRUS may separate CMT1A from other demyelinating CMTs. The large demyelinating CMTs HRUS spectrum may be related to its pathophysiological variability. 相似文献11.
Malcolm Proudfoot Freek van Ede Andrew Quinn Giles L. Colclough Joanne Wuu Kevin Talbot Michael Benatar Mark W. Woolrich Anna C. Nobre Martin R. Turner 《Clinical neurophysiology》2018,129(7):1479-1489
Objectives
The neural activity of the primary motor cortex is variably synchronised with contralateral peripheral electromyographic signals, which is thought to facilitate long-range communication through the motor system. Such corticomuscular coherence (CMC) is typically observed in the beta-band (15–30?Hz) range during steady force production. We aimed to measure pathological alteration to CMC resulting from ALS.Methods
CMC was appraised during a forearm grip task in 17 ALS patients contrasted against age-matched healthy controls. An exploratory comparison with a group of asymptomatic ALS gene carriers and neuropathy disease mimics was also undertaken. Neural signals were acquired by whole-head magnetoencephalography and localised via structural MRI to the motor cortices.Results
During light voluntary muscular contraction, beta-band CMC was significantly reduced in ALS patients compared to healthy controls. Propagation of motoric beta rhythms across the cortical hemispheres was also shown to be impaired in ALS patients. CMC was preserved in the asymptomatic gene carrier and did not distinguish ALS patients from neuropathy mimics.Conclusion
Functional connectivity metrics reveal an ALS-related decrease in both corticomuscular and interhemispheric communication during bilateral grip force production.Significance
MEG-derived beta oscillation coupling may be a potential biomarker of motor system dysfunction in ALS, against which to measure future therapeutic efficacy. 相似文献12.
Matteo Bologna Kelly Bertram Giulia Paparella Claudia Papi Daniele Belvisi Antonella Conte Antonio Suppa David R. Williams Alfredo Berardelli 《Clinical neurophysiology》2017,128(9):1547-1552
Objective
Abnormal primary motor cortex plasticity might be involved in the pathophysiology of progressive supranuclear palsy. In the present study we aimed to investigate possible abnormalities of depotentiation, a mechanism involved in plasticity regulation, in this condition.Methods
Primary motor cortex excitability, investigated with single and paired-pulse transcranial magnetic stimulation, as well as long-term potentiation-like plasticity and its reversibility, were studied using theta burst stimulation in 15 patients with progressive supranuclear palsy and 11 healthy controls. Participants underwent two sessions using (1) the intermittent theta-burst stimulation (potentiation protocol) and (2) intermittent theta-burst stimulation combined with a depotentiation protocol (a short continuous theta-burst stimulation).Results
Patients with PSP had higher corticospinal excitability and lower intracortical inhibition than healthy controls. Intermittent theta-burst stimulation elicited an abnormally increased long term potentiation-like effect in patients in comparison to healthy subjects. However, the depotentiation protocol was able to reverse the effects intermittent theta-burst stimulation on motor cortex excitability both in patients and in healthy controls.Conclusions
Altered primary motor cortex plasticity in patients with PSP does not reflect an abnormality of depotentiation.Significance
This study provides information for a deeper understanding of the possible pathophysiological mechanisms underlying the altered M1 plasticity in PSP. 相似文献13.
Daisuke Sawada Katsunori Fujii Sonoko Misawa Tadashi Shiohama Tomoyuki Fukuhara Mayuko Fujita Satoshi Kuwabara Naoki Shimojo 《Brain & development》2018,40(9):830-832
Background
Guillain-Barré syndrome is an acute immune-mediated peripheral polyneuropathy. Neuroimaging findings from patients with this syndrome have revealed gadolinium enhancement in the cauda equina and in the anterior and posterior nerve roots, but intra-spinal lesions have never been described.Aim
Herein, we report, for the first time, bilateral spinal anterior horn lesions in a patient with an acute motor axonal neuropathy form of Guillain-Barré syndrome.Case
The patient was a previously healthy 13-year-old Japanese girl, who exhibited acute-onset flaccid tetraplegia and loss of tendon reflexes.Results
Nerve conduction studies revealed motor axonal damage, leading to the diagnosis of acute motor axonal neuropathy. Notably, spinal magnetic resonance imaging revealed bilateral anterior horn lesions on T2-weighted imaging at the Th11–12 levels, as well as gadolinium enhancement of the cauda equina and anterior and posterior nerve roots. The anterior horn lesions were most prominent on day 18, and their signal intensity declined thereafter. Although intravenous treatment with immunoglobulins was immediately administered, the motor function was not completely regained.Conclusion
We propose that anterior spinal lesions might be responsible for the prolonged neurological disability of patients with Guillain-Barré syndrome, possibly produced by retrograde progression from the affected anterior nerve roots to the intramedullary roots, and the anterior horn motor neurons. 相似文献14.
Thomas Schüller Theo O.J. Gruendler René Huster Juan Carlos Baldermann Daniel Huys Markus Ullsperger Jens Kuhn 《Clinical neurophysiology》2018,129(9):1866-1872
Objective
Whether motor inhibition capabilities are impaired in Tourette’s syndrome (TS) remains inconclusive. The ability to suppress tics has been proposed to ensure normal motor control in uncomplicated, adult patients. The aim of the present study was to characterize cortical processes of motor inhibition and performance monitoring using event-related potentials (ERPs) elicited by a visual stop signal task.Methods
15 TS patients and 15 matched healthy controls performed a stop signal task while multi-channel EEG were recorded.Results
The behavioral results revealed no significant differences in inhibitory capabilities between groups. The latency of the P3 was discriminative of inhibition success, with shorter latencies for successful inhibition in both groups. P3 amplitude was not altered by inhibition success, but significantly attenuated for TS patients. Furthermore, the amplitude of the error-related negativity (ERN) was elevated while the error positivity (PE) was diminished for TS patients.Conclusion
In the stop signal task performance is not altered in adult TS patients but ERPs related to motor inhibition and performance monitoring are altered suggesting potential compensatory mechanisms.Significance
The results support the hypothesis of compensatory cortical mechanisms to ensure sufficient motor performance. 相似文献15.
Nidhi Garg Susanna B. Park James Howells Yu-ichi Noto Steve Vucic Con Yiannikas Susan E. Tomlinson William Huynh Neil G. Simon Emily K. Mathey Judith Spies John D. Pollard Arun V. Krishnan Matthew C. Kiernan 《Clinical neurophysiology》2018,129(10):2162-2169
Objective
To improve understanding of disease pathophysiology in anti-myelin-associated glycoprotein (anti-MAG) neuropathy to guide further treatment approaches.Methods
Anti-MAG neuropathy patients underwent clinical assessments, nerve conduction and excitability studies, and ultrasound assessment.Results
Patients demonstrated a distinctive axonal excitability profile characterised by a reduction in superexcitability [MAG: ?14.2?±?1.6% vs healthy controls (HC): ?21.8?±?1.2%; p?<?0.01] without alterations in most other excitability parameters. Mathematical modelling of nerve excitability recordings suggested that changes in axonal function could be explained by a 72.5% increase in juxtaparanodal fast potassium channel activation and an accompanying hyperpolarization of resting membrane potential (by 0.3?mV) resulting in a 94.2% reduction in discrepancy between anti-MAG data and the healthy control model. Superexcitability changes correlated strongly with clinical and neurophysiological parameters. Furthermore, structural assessments demonstrated a proximal pattern of nerve enlargement (C6 nerve root cross-sectional area: 15.9?±?8.1?mm2 vs HC: 9.1?±?2.3?mm2; p?<?0.05).Conclusions
The imaging and neurophysiological results support the pathogenicity of anti-MAG IgM. Widening between adjacent loops of paranodal myelin due to antibodies would expand the pathway from the node to the juxtaparanode, increasing activation of juxtaparanodal fast potassium channels, thereby impairing saltatory conduction.Significance
Potassium channel blockers may prove beneficial in restoring conduction closer to its normal state and improving nerve function in anti-MAG neuropathy. 相似文献16.
Yan Tang Bailin Liu Yuan Yang Chang-min Wang Li Meng Bei-sha Tang Ji-feng Guo 《Clinical neurophysiology》2018,129(12):2507-2516
Objective
Our study aims to extract significant disorder-associated patterns from whole brain functional connectivity to distinguish mild-moderate Parkinson’s disease (PD) patients from controls.Methods
Resting-state fMRI data were measured from thirty-six PD individuals and thirty-five healthy controls. Multivariate pattern analysis was applied to investigate whole-brain functional connectivity patterns in individuals with ‘mild-moderate’ PD. Additionally, the relationship between the asymmetry of functional connectivity and the side of the initial symptoms was also analyzed.Results
In a leave-one-out cross-validation, we got the generalization rate of 80.28% for distinguishing PD patients from controls. The most discriminative functional connectivity was found in cortical networks that included the default mode, sensorimotor and attention networks. Compared to patients with the left side initially affected, an increased abnormal functional connectivity was found in patients in whom the right side was initially affected.Conclusions
Our results indicated that discriminative functional connectivity is likely associated with disturbances of cortical networks involved in sensorimotor control and attention. The spatiotemporal patterns of motor asymmetry may be related to the lateralized dysfunction on the early stages of PD.Significance
This study identifies discriminative functional connectivity that is associated with disturbances of cortical networks. Our results demonstrated new evidence regarding the functional brain changes related to the unilateral motor symptoms of early PD. 相似文献17.
Shailesh Kantak Robert McGrath Nazaneen Zahedi Dustin Luchmee 《Clinical neurophysiology》2018,129(1):1-12
Objective
Given the presence of execution deficits after stroke, it is difficult to determine if patients with stroke have deficits in motor skill learning with the paretic arm. Here, we controlled for execution deficits while testing practice effects of the paretic arm on motor skill learning, long-term retention, and corticospinal excitability.Methods
Ten patients with unilateral stroke and ten age-matched controls practiced a kinematic arm skill for two days and returned for retention testing one-day and one-month post-practice. Motor skill learning was quantified as a change in speed–accuracy tradeoff from baseline to retention tests. Transcranial magnetic stimulation (TMS) was used to generate an input–output curve of the ipsilesional motor cortex (M1), and measure transcallosal inhibition from contralesional to ipsilesional M1.Results
While the control group had greater overall accuracy than the stroke group, both groups showed comparable immediate and long-term improvements with practice. Skill improvements were accompanied by greater excitability of the ipsilesional corticospinal system and reduced transcallosal inhibition from contralesional to ipsilesional M1.Conclusions
When execution deficits are accounted for, patients with stroke demonstrate relatively intact motor skill learning with the paretic arm. Paretic arm learning is accompanied by modulations in corticospinal and transcallosal mechanisms.Significance
Functional recovery after stroke relies on ability for skill learning and the underlying mechanisms. 相似文献18.
Maarten R.C. van den Heuvel Erwin E.H. van Wegen Peter J. Beek Gert Kwakkel Andreas Daffertshofer 《Clinical neurophysiology》2018,129(7):1357-1365
Objective
In patients with Parkinson’s disease (PD), augmented visual feedback (VF) can improve functional motor performance. Conversely, they appear to rely more on visual information than healthy subjects, which is unfavorable when this information is unreliable. Cortical beta activity is thought to be associated with the need for motor adaptation. We here compared event-related EEG parameters during a whole-body postural weight-shifting task between congruent and incongruent feedback conditions.Methods
Twenty-four patients with PD and fifteen healthy, age- and gender-matched controls performed rhythmic swaying movements. VF was presented in real-time (congruent), delayed (incongruent), or was entirely absent. We estimated source activity in four regions-of-interest and determined motor-related spectral power and power modulation in alpha and beta frequency bands.Results
For congruent VF no significant differences in cortical activity between the two groups were present. For incongruent VF, the PD group showed significantly higher beta modulation in primary motor cortex, and higher alpha modulation in primary visual cortex.Conclusions
Event-related beta modulation in the motor network and alpha modulation in visual areas discriminated between groups, suggesting altered visuomotor processing in PD patients.Significance
This study finds evidence for increased modulation of alpha/beta activity during perceptual-motor tasks in PD, possibly indicating an unwarranted higher confidence in VF. 相似文献19.
Stefanie Schreiber Frank Schreiber Grazyna Debska-Vielhaber Cornelia Garz Nathalie Hensiek Judith Machts Susanne Abdulla Reinhard Dengler Susanne Petri Peter J. Nestor Stefan Vielhaber 《Clinical neurophysiology》2018,129(7):1438-1443
Objective
We aimed to assess whether differential peripheral nerve involvement parallels dissociated forearm muscle weakness in amyotrophic lateral sclerosis (ALS).Methods
The analysis comprised 41 ALS patients and 18 age-, sex-, height- and weight-matched healthy controls. Strength of finger-extension and -flexion was measured using the Medical Research Council (MRC) scale. Radial, median and ulnar nerve sonographic cross-sectional area (CSA) and echogenicity, expressed by the hypoechoic fraction (HF), were determined.Results
In ALS, finger extensors were significantly weaker than finger flexors. Sonographic evaluation revealed peripheral nerve atrophy, affecting various nerve segments in ALS. HF was unaltered.Conclusions
This systematic study confirmed a long-observed physical examination finding in ALS – weakness in finger-extension out of proportion to finger-flexion. This phenomenon was not related to any particular sonographic pattern of upper limb peripheral nerve alteration.Significance
In ALS, dissociated forearm muscle weakness could aid in the disease’s diagnosis. Nerve ultrasound did not provide additional information on the differential involvement of finger-extension and finger-flexion strength. 相似文献20.
Christos Ganos Elisa R. Ferrè Angela Marotta Panagiotis Kassavetis John Rothwell Kailash P. Bhatia Patrick Haggard 《Clinical neurophysiology》2018,129(2):466-472