Electroencephalogram phase synchrony correlates with post-stroke upper limb motor impairment

2017 ◽  
Vol 381 ◽  
pp. 600-601
Author(s):  
T. Kawano ◽  
N. Hattori ◽  
Y. Uno ◽  
M. Hatakenaka ◽  
H. Yagura ◽  
...  
Keyword(s):  
Upper Limb ◽  
Motor Impairment ◽  
Phase Synchrony ◽  
Post Stroke

scholarly journals Effect of post-stroke spasticity on voluntary movement of the upper limb

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Hadar Lackritz ◽  
Yisrael Parmet ◽  
Silvi Frenkel-Toledo ◽  
Melanie C. Baniña ◽  
Nachum Soroker ◽  
...  
Keyword(s):  
Upper Limb ◽  
Target Location ◽  
Distance Measure ◽  
Movement Time ◽  
Motor Impairment ◽  
Reach To Grasp ◽  
Motion Patterns ◽  
Post Stroke ◽  
The Impact ◽  
Elbow Motion

Abstract Background Hemiparesis following stroke is often accompanied by spasticity. Spasticity is one factor among the multiple components of the upper motor neuron syndrome that contributes to movement impairment. However, the specific contribution of spasticity is difficult to isolate and quantify. We propose a new method of quantification and evaluation of the impact of spasticity on the quality of movement following stroke. Methods Spasticity was assessed using the Tonic Stretch Reflex Threshold (TSRT). TSRT was analyzed in relation to stochastic models of motion to quantify the deviation of the hemiparetic upper limb motion from the normal motion patterns during a reaching task. Specifically, we assessed the impact of spasticity in the elbow flexors on reaching motion patterns using two distinct measures of the ‘distance’ between pathological and normal movement, (a) the bidirectional Kullback–Liebler divergence (BKLD) and (b) Hellinger’s distance (HD). These measures differ in their sensitivity to different confounding variables. Motor impairment was assessed clinically by the Fugl-Meyer assessment scale for the upper extremity (FMA-UE). Forty-two first-event stroke patients in the subacute phase and 13 healthy controls of similar age participated in the study. Elbow motion was analyzed in the context of repeated reach-to-grasp movements towards four differently located targets. Log-BKLD and HD along with movement time, final elbow extension angle, mean elbow velocity, peak elbow velocity, and the number of velocity peaks of the elbow motion were computed. Results Upper limb kinematics in patients with lower FMA-UE scores (greater impairment) showed greater deviation from normality when the distance between impaired and normal elbow motion was analyzed either with the BKLD or HD measures. The severity of spasticity, reflected by the TSRT, was related to the distance between impaired and normal elbow motion analyzed with either distance measure. Mean elbow velocity differed between targets, however HD was not sensitive to target location. This may point at effects of spasticity on motion quality that go beyond effects on velocity. Conclusions The two methods for analyzing pathological movement post-stroke provide new options for studying the relationship between spasticity and movement quality under different spatiotemporal constraints.

scholarly journals Interhemispheric Pathways Are Important for Motor Outcome in Individuals with Chronic and Severe Upper Limb Impairment Post Stroke

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Kathryn S. Hayward ◽  
Jason L. Neva ◽  
Cameron S. Mang ◽  
Sue Peters ◽  
Katie P. Wadden ◽  
...  
Keyword(s):  
Corpus Callosum ◽  
Upper Limb ◽  
Motor Impairment ◽  
Post Stroke ◽  
Significant Difference ◽  
Motor Outcome ◽  
Wolf Motor Function Test ◽  
Severe Group ◽  
And Function ◽  
Motor Outcomes

Background. Severity of arm impairment alone does not explain motor outcomes in people with severe impairment post stroke.Objective. Define the contribution of brain biomarkers to upper limb motor outcomes in people with severe arm impairment post stroke.Methods. Paretic arm impairment (Fugl-Meyer upper limb, FM-UL) and function (Wolf Motor Function Test rate, WMFT-rate) were measured in 15 individuals with severe (FM-UL ≤ 30/66) and 14 with mild–moderate (FM-UL > 40/66) impairment. Transcranial magnetic stimulation and diffusion weight imaging indexed structure and function of the corticospinal tract and corpus callosum. Separate models of the relationship between possible biomarkers and motor outcomes at a single chronic (≥6 months) time point post stroke were performed.Results. Age (ΔR20.365,p=0.017) and ipsilesional-transcallosal inhibition (ΔR20.182,p=0.048) explained a 54.7% (p=0.009) variance in paretic WMFT-rate. Prefrontal corpus callous fractional anisotropy (PF-CC FA) alone explained 49.3% (p=0.007) variance in FM-UL outcome. The same models did not explain significant variance in mild–moderate stroke. In the severe group, k-means cluster analysis of PF-CC FA distinguished two subgroups, separated by a clinically meaningful and significant difference in motor impairment (p=0.049) and function (p=0.006) outcomes.Conclusion. Corpus callosum function and structure were identified as possible biomarkers of motor outcome in people with chronic and severe arm impairment.

scholarly journals Association between aphasia severity and brain network alterations after stroke assessed using the electroencephalographic phase synchrony index

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Teiji Kawano ◽  
Noriaki Hattori ◽  
Yutaka Uno ◽  
Megumi Hatakenaka ◽  
Hajime Yagura ◽  
...  
Keyword(s):  
Resting State ◽  
Motor Impairment ◽  
Brain Network ◽  
Phase Synchrony ◽  
Beta Band ◽  
Post Stroke ◽  
Expressive Function ◽  
Delta Band ◽  
Network Status ◽  
The Right

AbstractElectroencephalographic synchrony can help assess brain network status; however, its usefulness has not yet been fully proven. We developed a clinically feasible method that combines the phase synchrony index (PSI) with resting-state 19-channel electroencephalography (EEG) to evaluate post-stroke motor impairment. In this study, we investigated whether our method could be applied to aphasia, a common post-stroke cognitive impairment. This study included 31 patients with subacute aphasia and 24 healthy controls. We assessed the expressive function of patients and calculated the PSIs of three motor language-related regions: frontofrontal, left frontotemporal, and right frontotemporal. Then, we evaluated post-stroke network alterations by comparing PSIs of the patients and controls and by analyzing the correlations between PSIs and aphasia scores. The frontofrontal PSI (beta band) was lower in patients than in controls and positively correlated with aphasia scores, whereas the right frontotemporal PSI (delta band) was higher in patients than in controls and negatively correlated with aphasia scores. Evaluation of artifacts suggests that this association is attributed to true synchrony rather than spurious synchrony. These findings suggest that post-stroke aphasia is associated with alternations of two different networks and point to the usefulness of EEG PSI in understanding the pathophysiology of aphasia.

scholarly journals Movement kinematics and proprioception in post-stroke spasticity: assessment using the Kinarm robotic exoskeleton

2019 ◽  
Vol 16 (1) ◽  
Author(s):  
George Mochizuki ◽  
Andrew Centen ◽  
Myles Resnick ◽  
Catherine Lowrey ◽  
Sean P. Dukelow ◽  
...  
Keyword(s):  
Upper Limb ◽  
Motor Impairment ◽  
Movement Patterns ◽  
Visually Guided ◽  
Central Target ◽  
Robotic Exoskeleton ◽  
Visually Guided Reaching ◽  
Post Stroke ◽  
Temporal Features ◽  
Limb Spasticity

Abstract Background Motor impairment after stroke interferes with performance of everyday activities. Upper limb spasticity may further disrupt the movement patterns that enable optimal function; however, the specific features of these altered movement patterns, which differentiate individuals with and without spasticity, have not been fully identified. This study aimed to characterize the kinematic and proprioceptive deficits of individuals with upper limb spasticity after stroke using the Kinarm robotic exoskeleton. Methods Upper limb function was characterized using two tasks: Visually Guided Reaching, in which participants moved the limb from a central target to 1 of 4 or 1 of 8 outer targets when cued (measuring reaching function) and Arm Position Matching, in which participants moved the less-affected arm to mirror match the position of the affected arm (measuring proprioception), which was passively moved to 1 of 4 or 1 of 9 different positions. Comparisons were made between individuals with (n = 35) and without (n = 35) upper limb post-stroke spasticity. Results Statistically significant differences in affected limb performance between groups were observed in reaching-specific measures characterizing movement time and movement speed, as well as an overall metric for the Visually Guided Reaching task. While both groups demonstrated deficits in proprioception compared to normative values, no differences were observed between groups. Modified Ashworth Scale score was significantly correlated with these same measures. Conclusions The findings indicate that individuals with spasticity experience greater deficits in temporal features of movement while reaching, but not in proprioception in comparison to individuals with post-stroke motor impairment without spasticity. Temporal features of movement can be potential targets for rehabilitation in individuals with upper limb spasticity after stroke.

scholarly journals Comparing a novel neuroanimation experience to conventional therapy for high-dose, intensive upper-limb training in subacute stroke: The SMARTS2 randomized trial

2020 ◽  
Author(s):  
John W Krakauer ◽  
Tomoko Kitago ◽  
Jeff Goldsmith ◽  
Omar Ahmad ◽  
Promit Roy ◽  
...  
Keyword(s):  
Upper Limb ◽  
High Intensity ◽  
Animal Studies ◽  
Motor Impairment ◽  
High Dose ◽  
Time On Task ◽  
Historical Cohort ◽  
Post Stroke ◽  
Subacute Stroke ◽  
Secondary Outcomes

Background: Evidence from animal studies suggests that greater reductions in post-stroke motor impairment can be attained with significantly higher doses and intensities of therapy focused on movement quality. These studies also indicate a dose-timing interaction, with more pronounced effects if high-intensity therapy is delivered in the acute/subacute, rather than chronic, post-stroke period. Objective: To compare two approaches of delivering high-intensity, high-dose upper limb therapy in patients with subacute stroke: a novel exploratory neuro-animation therapy (NAT), and modified conventional occupational therapy (COT). Methods: Twenty-four patients were randomized to NAT or COT and underwent 30 sessions of 60 minutes time-on-task in addition to standard care. The primary outcome was the Fugl-Meyer Upper Extremity motor score (FM-UE). Secondary outcomes included: Action Research Arm Test (ARAT), grip strength, Stroke Impact Scale (SIS) hand domain, and upper-limb kinematics. Outcomes were assessed at baseline, and days 3, 90, and 180 post-training. Both groups were compared to a matched historical cohort (HC), which received only 30 minutes of upper limb therapy per day. Results: There were no significant between-group differences in FM-UE change or any of the secondary outcomes at any timepoint. Both high-dose groups showed greater recovery on the ARAT (7.3 ±2.9 pts, p=0.011), but not the FM-UE (1.4 ±2.6 pts, p =0.564) when compared to the HC. Conclusions: Two forms of high-dose intensive upper limb therapy produced greater activity but not impairment improvements compared with regular care. Neuroanimation may offer a new enjoyable, efficient and scalable way to deliver increased upper limb therapy.

scholarly journals The Strength of the Corticospinal Tract Not the Reticulospinal Tract Determines Upper-Limb Impairment Level and Capacity for Skill-Acquisition in the Sub-Acute Post-Stroke Period

2021 ◽  
pp. 154596832110282
Author(s):  
Ulrike Hammerbeck ◽  
Sarah F. Tyson ◽  
Prawin Samraj ◽  
Kristen Hollands ◽  
John W. Krakauer ◽  
...  
Keyword(s):  
Acute Stroke ◽  
Usual Care ◽  
Skill Acquisition ◽  
Upper Limb ◽  
Motor Impairment ◽  
Single Pulse ◽  
Main Determinant ◽  
Post Stroke ◽  
Reticulospinal Tract ◽  
The Impact

Background. Upper-limb impairment in patients with chronic stroke appears to be partly attributable to an upregulated reticulospinal tract (RST). Here, we assessed whether the impact of corticospinal (CST) and RST connectivity on motor impairment and skill-acquisition differs in sub-acute stroke, using transcranial magnetic stimulation (TMS)–based proxy measures. Methods. Thirty-eight stroke survivors were randomized to either reach training 3-6 weeks post-stroke (plus usual care) or usual care only. At 3, 6 and 12 weeks post-stroke, we measured ipsilesional and contralesional cortical connectivity (surrogates for CST and RST connectivity, respectively) to weak pre-activated triceps and deltoid muscles with single pulse TMS, accuracy of planar reaching movements, muscle strength (Motricity Index) and synergies (Fugl-Meyer upper-limb score). Results. Strength and presence of synergies were associated with ipsilesional (CST) connectivity to the paretic upper-limb at 3 and 12 weeks. Training led to planar reaching skill beyond that expected from spontaneous recovery and occurred for both weak and strong ipsilesional tract integrity. Reaching ability, presence of synergies, skill-acquisition and strength were not affected by either the presence or absence of contralesional (RST) connectivity. Conclusion. The degree of ipsilesional CST connectivity is the main determinant of proximal dexterity, upper-limb strength and synergy expression in sub-acute stroke. In contrast, there is no evidence for enhanced contralesional RST connectivity contributing to any of these components of impairment. In the sub-acute post-stroke period, the balance of activity between CST and RST may matter more for the paretic phenotype than RST upregulation per se.

scholarly journals TMS-Induced Central Motor Conduction Time at the Non-Infarcted Hemisphere is Associated with Spontaneous Motor Recovery of the Paretic Upper Limb after Severe Stroke

2021 ◽  
Vol 11 (5) ◽  
pp. 648
Author(s):  
Maurits Hoonhorst ◽  
Rinske Nijland ◽  
Cornelis Emmelot ◽  
Boudewijn Kollen ◽  
Gert Kwakkel
Keyword(s):  
Ischemic Stroke ◽  
Upper Limb ◽  
Normative Data ◽  
Motor Impairment ◽  
Motor Recovery ◽  
Conduction Time ◽  
Stroke Patients ◽  
Severe Stroke ◽  
Central Motor Conduction Time ◽  
Post Stroke

Background: Stroke affects the neuronal networks of the non-infarcted hemisphere. The central motor conduction time (CMCT) induced by transcranial magnetic stimulation (TMS) could be used to determine the conduction time of the corticospinal tract of the non-infarcted hemisphere after a stroke. Objectives: Our primary aim was to demonstrate the existence of prolonged CMCT in the non-infarcted hemisphere, measured within the first 48 h when compared to normative data, and secondly, if the severity of motor impairment of the affected upper limb was significantly associated with prolonged CMCTs in the non-infarcted hemisphere when measured within the first 2 weeks post stroke. Methods: CMCT in the non-infarcted hemisphere was measured in 50 patients within 48 h and at 11 days after a first-ever ischemic stroke. Patients lacking significant spontaneous motor recovery, so-called non-recoverers, were defined as those who started below 18 points on the FM-UE and showed less than 6 points (10%) improvement within 6 months. Results: CMCT in the non-infarcted hemisphere was prolonged in 30/50 (60%) patients within 48 h and still in 24/49 (49%) patients at 11 days. Sustained prolonged CMCT in the non-infarcted hemisphere was significantly more frequent in non-recoverers following FM-UE. Conclusions: The current study suggests that CMCT in the non-infarcted hemisphere is significantly prolonged in 60% of severely affected, ischemic stroke patients when measured within the first 48 h post stroke. The likelihood of CMCT is significantly higher in non-recoverers when compared to those that show spontaneous motor recovery early post stroke.

scholarly journals Time Course of Wrist Hyper-Resistance in Relation to Upper Limb Motor Recovery Early Post Stroke

2020 ◽  
Vol 34 (8) ◽  
pp. 690-701
Author(s):  
Aukje Andringa ◽  
Carel Meskers ◽  
Ingrid van de Port ◽  
Erwin van Wegen ◽  
Gert Kwakkel
Keyword(s):  
Upper Limb ◽  
Mixed Models ◽  
Time Course ◽  
Motor Impairment ◽  
Motor Recovery ◽  
Motor Deficits ◽  
Stroke Patients ◽  
Post Stroke ◽  
Resistance Components ◽  
Finger Extension

Background. Patients with an upper limb motor impairment are likely to develop wrist hyper-resistance during the first months post stroke. The time course of wrist hyper-resistance in terms of neural and biomechanical components, and their interaction with motor recovery, is poorly understood. Objective. To investigate the time course of neural and biomechanical components of wrist hyper-resistance in relation to upper limb motor recovery in the first 6 months post stroke. Methods. Neural (NC), biomechanical elastic (EC), and viscous (VC) components of wrist hyper-resistance (NeuroFlexor device), and upper limb motor recovery (Fugl-Meyer upper extremity scale [FM-UE]), were assessed in 17 patients within 3 weeks and at 5, 12, and 26 weeks post stroke. Patients were stratified according to the presence of voluntary finger extension (VFE) at baseline. Time course of wrist hyper-resistance components and assumed interaction effects were analyzed using linear mixed models. Results. On average, patients without VFE at baseline (n = 8) showed a significant increase in NC, EC, and VC, and an increase in FM-UE from 13 to 26 points within the first 6 months post stroke. A significant increase in NC within 5 weeks preceded a significant increase in EC between weeks 12 and 26. Patients with VFE at baseline (n = 9) showed, on average, no significant increase in components from baseline to 6 months whereas FM-UE scores improved from 38 to 60 points. Conclusion. Our findings suggest that the development of neural and biomechanical wrist hyper-resistance components in patients with severe baseline motor deficits is determined by lack of spontaneous neurobiological recovery early post stroke.

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