Motor Stroke Research Articles

Right hemisphere stroke is linked to reduced social connectedness in the UK Biobank cohort

Social connectedness is fundamental to health and life satisfaction. Empathic capacities that support social connections are commonly impaired following damage to the brain’s right hemisphere, but how these acquired socio-emotional deficits correspond to real-world social outcomes remains unclear. Using anatomical brain imaging and behavioral data from a large sample of stroke survivors included in the UK Biobank (n = 209), we link damage to regions of the right hemisphere involved in emotion recognition to lower social relationship satisfaction and higher loneliness. The effect was driven by lesions to the right anterior insula and not explained by stroke extent and motor function; it was further corroborated by an exploratory analysis of social decline in a few participants for whom data were available from before and after a stroke to the right anterior insula (n = 3; comparison n = 13). These correlational findings provide new insight into the role of the right hemisphere in maintaining social connections and bear important implications for treatment and rehabilitation post-stroke.

Characterizing practice-dependent motor learning after a stroke.

After stroke, patients must learn to use residual motor function correctly. Consistently, motor learning is crucial in stroke motor recovery. We assessed motor performance, practice-dependent on-line motor learning, and factors potentially affecting them in stroke patients. This is a cross-sectional observational study. Twenty-six patients with first brain stroke leading to upper limb motor deficit in the subacute or chronic timeframe were enrolled. They performed a Finger Tapping Task (FTT) with both the affected and unaffected limbs. We assessed how patients learn to perform motor tasks despite the motor deficit and the differences in performance between the unaffected and affected limbs. Furthermore, by randomizing the order, we evaluated the possible inter-limb transfer of motor learning (i.e. transfer of a motor skill learned in one limb to the opposite one). Moreover, sleep, attention, anxiety, and depression were assessed through specific tests and questionnaires. Improved FTT accuracy and completed sequences for the affected limb were observed, even if lower than for the unaffected one. Furthermore, when patients initially performed the FTT with the unaffected limb, they showed higher accuracy in subsequent task completion with the affected limb than subjects who started with the affected limb. Only anxiety and attentional abilities showed significant correlations with motor performance. This work provides relevant insights into motor learning in stroke. Practice-dependent on-line motor learning is preserved in stroke survivors, and an inter-limb transfer effect can be observed. Attentional abilities and anxiety can affect learning after stroke, even if the effect of other factors cannot be excluded.

Effects of repetitive transcranial magnetic stimulation at different targets on brain function in stroke patients: a randomized controlled trial.

Repetitive transcranial magnetic stimulation (rTMS) can improve post stroke motor function. However, there is little research on targets. The purpose of this study is to investigate the effects of rTMS therapy with different targets on post stroke motor function and neural plasticity. Fifty-four subjects were randomly divided into M1 (Primary motor area) group, SMA (supplementary motor area) group and Sham group, and were given 10 Hz on the affected M1 area, SMA area and sham stimulation rTMS. The primary outcomes included Fugl-Meyer Assessment Upper Extremity Scale (FMA-UE), Fugl-Meyer Assessment Lower Extremity Scale (FMA-LE) and Berg balance scale (BBS). Secondary outcomes: amplitude of low frequency fluctuation (ALFF), regional homogeneity (ReHo) and functional connectivity (FC) were analyzed by functional magnetic resonance imaging (fMRI) to evaluate brain functional activation and functional connectivity changes. The 2-way repeated-measures ANOVA revealed a significant group × time interaction (F = 23.494, p < 0.001; F = 10.801, p < 0.001; F = 17.812, p < 0.001) in the FMA-UE, FMA-LE and BBS scores. Post hoc analysis indicated that 4 weeks of SMA rTMS resulted in an increase in FMA-UE, FMA-LE and BBS scores compared with Sham group (p = 0.006; p = 0.033; p = 0.012), SMA group was significantly increased in BBS compared with M1 group (p = 0.034). Moreover, there were significant effects of time in all 3 groups in the FMA-UE, FMA-LE and BBS scores (p < 0.001). In addition, the increase of ALFF in the supramarginal gyrus on the affected side was correlated with better FMA-UE recovery, the increase of ALFF in the middle temporal gyrus and the middle frontal gyrus on the affected side was positively correlated with the improvement of BBS, and the ALFF in the cerebellum on the healthy side was negatively correlated with the improvement of BBS. There was a positive correlation between FC (SMA - ipsilateral cerebellum) changes and BBS changes in SMA group. In conclusion, SMA-rTMS intervention has a better recovery effect on motor dysfunction after stroke than Sham-rTMS. SMA-rTMS led to similar improvement on motor function but significantly greater improvement on balance compared to M1-rTMS, and this may pave a new way for stroke rehabilitation. Registration number: ChiCTR2200060955, https://www.chictr.org.cn/.

Gut microbiota and functional outcome after ischemic stroke: a Mendelian randomization study.

Previous studies have shown that gut microbiota dysbiosis could affect clinical prognosis through an unknown mechanism. However, the causal relationship between the gut microbiota and the functional outcome after ischemic stroke remains unclear. We aimed to investigate the causal association between the gut microbiota and the functional outcome after ischemic stroke using Mendelian randomization (MR). Genetic instrumental variables associated with 211 bacterial traits were obtained from the MiBioGen consortium (N = 18,340). Data from genome-wide association studies (GWAS) for functional outcome after ischemic stroke were obtained from two phenotypes (i.e., overall stroke outcome and motor recovery). The inverse variance weighted method was used to estimate the causal association. Enrichment analysis was conducted based on the results of the MR analyses. The genetically predicted family Peptostreptococcaceae (OR = 0.63, 95% CI = 0.41-0.98, p = 0.038) and the genera LachnospiraceaeNK4A136 group (OR = 0.65, 95% CI = 0.43-1.00, p = 0.048), LachnospiraceaeUCG004 (OR = 0.54, 95% CI = 0.33-0.90, p = 0.017), and Odoribacter (OR = 0.40, 95% CI = 0.21-0.77, p = 0.006) presented a suggestive association with favorable functional outcome, while the genera Eubacterium oxidoreducens group (OR = 1.77, 95% CI = 1.11-2.84, p = 0.018) and RuminococcaceaeUCG005 (OR = 1.85, 95% CI = 1.15-2.96, p = 0.010) were associated with unfavorable functional outcome. The genetically predicted family Oxalobacteraceae (OR = 2.12, 95% CI = 1.10-4.11, p = 0.025) and the genus RuminococcaceaeUCG014 (OR = 4.17, 95% CI = 1.29-13.52, p = 0.017) showed a suggestive association with motor recovery, while the order Enterobacteriales (OR = 0.14, 95% CI = 0.02-0.87, p = 0.035) and the family Enterobacteriaceae (OR = 0.14, 95% CI = 0.02-0.87, p = 0.035) were associated with motor weakness. Enrichment analysis revealed that regulation of the synapse structure or activity may be involved in the effect of the gut microbiota on the functional outcome after ischemic stroke. This study provides genetic support that the gut microbiota, especially those associated with short-chain fatty acids, could affect stroke prognosis by mediating synapse function. Our findings suggest that modifying the composition of the gut microbiota could improve the prognosis of ischemic stroke.

Brain state-dependent repetitive transcranial magnetic stimulation for motor stroke rehabilitation: a proof of concept randomized controlled trial.

In healthy subjects, repetitive transcranial magnetic stimulation (rTMS) targeting the primary motor cortex (M1) demonstrated plasticity effects contingent on electroencephalography (EEG)-derived excitability states, defined by the phase of the ongoing sensorimotor μ-oscillation. The therapeutic potential of brain state-dependent rTMS in the rehabilitation of upper limb motor impairment post-stroke remains unexplored. Proof-of-concept trial to assess the efficacy of rTMS, synchronized to the sensorimotor μ-oscillation, in improving motor impairment and reducing upper-limb spasticity in stroke patients. We conducted a parallel group, randomized double-blind controlled trial in 30 chronic stroke patients (clinical trial registration number: NCT05005780). The experimental intervention group received EEG-triggered rTMS of the ipsilesional M1 [1,200 pulses; 0.33 Hz; 100% of the resting motor threshold (RMT)], while the control group received low-frequency rTMS of the contralesional motor cortex (1,200 pulses; 1 Hz, 115% RMT), i.e., an established treatment protocol. Both groups received 12 rTMS sessions (20 min, 3× per week, 4 weeks) followed by 50 min of physiotherapy. The primary outcome measure was the change in upper-extremity Fugl-Meyer assessment (FMA-UE) scores between baseline, immediately post-treatment and 3 months' follow-up. Both groups showed significant improvement in the primary outcome measure (FMA-UE) and the secondary outcome measures. This included the reduction in spasticity, measured objectively using the hand-held dynamometer, and enhanced motor function as measured by the Wolf Motor Function Test (WMFT). There were no significant differences between the groups in any of the outcome measures. The application of brain state-dependent rTMS for rehabilitation in chronic stroke patients is feasible. This pilot study demonstrated that the brain oscillation-synchronized rTMS protocol produced beneficial effects on motor impairment, motor function and spasticity that were comparable to those observed with an established therapeutic rTMS protocol. ClinicalTrials.gov, identifier [NCT05005780].

Pedaling Asymmetry Reflected by Bilateral EMG Complexity in Chronic Stroke.

This study examines pedaling asymmetry using the electromyogram (EMG) complexity of six bilateral lower limb muscles for chronic stroke survivors. Fifteen unilateral chronic stroke and twelve healthy participants joined passive and volitional recumbent pedaling tasks using a self-modified stationary bike with a constant speed of 25 revolutions per minute. The fuzzy approximate entropy (fApEn) was adopted in EMG complexity estimation. EMG complexity values of stroke participants during pedaling were smaller than those of healthy participants (p = 0.002). For chronic stroke participants, the complexity of paretic limbs was smaller than that of non-paretic limbs during the passive pedaling task (p = 0.005). Additionally, there was a significant correlation between clinical scores and the paretic EMG complexity during passive pedaling (p = 0.022, p = 0.028), indicating that the paretic EMG complexity during passive movement might serve as an indicator of stroke motor function status. This study suggests that EMG complexity is an appropriate quantitative tool for measuring neuromuscular characteristics in lower limb dynamic movement tasks for chronic stroke survivors.

An Experiment Using Functional Near-Infrared Spectroscopy and Robot-Assisted Multi-Joint Pointing Movements of the Lower Limb.

Stroke affects approximately 17 million individuals worldwide each year and is a leading cause of long-term disability. Robotic therapy has shown promise in helping stroke patients regain lost motor functions. One potential avenue for increasing the understanding of how motor recovery occurs is to study brain activation during the movements that are targeted by therapy in healthy individuals. Functional Near-Infrared Spectroscopy (fNIRS) has emerged as a promising neuroimaging technique for examining neural underpinnings of motor function. This study aimed to investigate fNIRS neural correlates of complex lower limb movements in healthy subjects. Participants were asked to perform cycles of rest and movement for 6 min using a robotic device for motor rehabilitation. The task required coordinated knee and ankle joint movements to point to targets displayed on a computer screen. Two experimental conditions with different levels of movement assistance provided by the robot were explored. The results showed that the fNIRS protocol effectively detected brain regions associated with motor control during the task. Notably, all subjects exhibited greater activation in the contralateral premotor area during the no-assistance condition compared to the assisted condition. In conclusion, fNIRS appears to be a valuable approach for detecting changes in oxyhemoglobin concentration associated with multi-joint pointing movements of the lower limb. This research might contribute to the understanding of stroke motor recovery mechanisms and might pave the way for improved rehabilitation treatments for stroke patients. However, further research is needed to fully elucidate the potential of fNIRS in studying motor function and its applications in clinical settings.

QUANTIFICATION OF KINEMATIC AND MOTOR VARIABLES IN PARACANOEING THROUGH THE ACTION CAMERA: A STUDY EXPLORATORY

Paracanoeing is a speed boating sport, practiced by men and women, who seek to cover a distance of 200 meters in the shortest possible time. To generate the propulsion of the vessel and overcome the aerodynamic and hydrodynamic drags, the athletes perform the stroke motor gesture, which consists of bilateral cyclic and symmetrical movements with a two-blade paddle. Since, the motor performance in the modality can be influenced by motor aspects related to rowing and the athlete's ability to produce and maintain high speed indexes. Thus, the objective of the present study was to explore the different ways of quantifying variables through GPS and action camera technologies, as well as programs that systematize this information, being able to transform it into graphs through commonly used statistical programs. With this, it is possible to perform the interpretation and quantification of the variables through technological equipment, GPS and action camera, the data of a volunteer, a beginner athlete of paracanoeing, were analyzed, the speed, paddling index, paddling phases were analyzed ( water and air) and paddling frequency. In this way, the study opens the possibility to use the technique in paracanoeing training programs, with the objective of evaluating the athlete, since through the quantification of the variables it is possible to map the athlete's performance in each variable. Received: 2024/02/17 Reformulated: 2024/04/23 Accepted: 2024/04/23

Interrater reliability of the Fugl-Meyer Motor assessment in stroke patients: a quality management project within the ESTREL study.

The Fugl-Meyer Motor Assessment (FMMA) is recommended for evaluating stroke motor recovery in clinical practice and research. However, its widespread use requires refined reliability data, particularly across different health professions. We therefore investigated the interrater reliability of the FMMA scored by a physical therapist and a physician using video recordings of stroke patients. The FMMA videos of 50 individuals 3 months post stroke (28 females, mean age 71.64 years, median National Institutes of Health Stroke Scale score 3.00) participating in the ESTREL trial (Enhancement of Stroke Rehabilitation with Levodopa: a randomized placebo-controlled trial) were independently scored by two experienced assessors (i.e., a physical therapist and a physician) with specific training to ensure consistency. As primary endpoint, the interrater reliability was calculated for the total scores of the entire FMMA and the total scores of the FMMA for the upper and lower extremities using intraclass correlation coefficients (ICC). In addition, Spearman's rank order correlation coefficients (Spearman's rho) were calculated for the total score and subscale levels. Secondary endpoints included the FMMA item scores using percentage agreement, weighted Cohen's kappa coefficients, and Gwet's AC1/AC2 coefficients. ICCs were 0.98 (95% confidence intervals (CI) 0.96-0.99) for the total scores of the entire FMMA, 0.98 (95% CI 0.96-0.99) for the total scores of the FMMA for the upper extremity, and 0.85 (95% CI 0.70-0.92) for the total scores of the FMMA for the lower extremity. Spearman's rho ranged from 0.61 to 0.94 for total and subscale scores. The interrater reliability at the item level of the FMMA showed (i) percentage agreement values with a median of 77% (range 44-100%), (ii) weighted Cohen's kappa coefficients with a median of 0.69 (range 0.00-0.98) and (iii) Gwet's AC1/AC2 coefficients with a median of 0.84 (range 0.42-0.98). The FMMA appears to be a highly reliable measuring instrument at the overall score level for assessors from different health professions. The FMMA total scores seem to be suitable for the quantitative measurement of stroke recovery in both clinical practice and research, although there is potential for improvement at the item level.

Exploring the Prospects of Transcranial Electrical Stimulation (tES) as a Therapeutic Intervention for Post-Stroke Motor Recovery: A Narrative Review.

Stroke survivors often have motor impairments and related functional deficits. Transcranial Electrical Stimulation (tES) is a rapidly evolving field that offers a wide range of capabilities for modulating brain function, and it is safe and inexpensive. It has the potential for widespread use for post-stroke motor recovery. Transcranial Direct Current Stimulation (tDCS), Transcranial Alternating Current Stimulation (tACS), and Transcranial Random Noise Stimulation (tRNS) are three recognized tES techniques that have gained substantial attention in recent years but have different mechanisms of action. tDCS has been widely used in stroke motor rehabilitation, while applications of tACS and tRNS are very limited. The tDCS protocols could vary significantly, and outcomes are heterogeneous. the current review attempted to explore the mechanisms underlying commonly employed tES techniques and evaluate their prospective advantages and challenges for their applications in motor recovery after stroke. tDCS could depolarize and hyperpolarize the potentials of cortical motor neurons, while tACS and tRNS could target specific brain rhythms and entrain neural networks. Despite the extensive use of tDCS, the complexity of neural networks calls for more sophisticated modifications like tACS and tRNS.

A Clinical Randomized Controlled Study of Low-Frequency rTMS Therapy on Lower Limb Motor Dysfunction after Stroke

Objective: To investigate the efficacy and safety of low-frequency repetitive transcranial magnetic stimulation (rTMS) for the treatment of lower limb motor dysfunction after stroke. Methods: A total of 96 patients with stroke and lower limb motor dysfunction were enrolled in this study, and were randomly divided into the experimental group and the sham stimulation group using the method of calculator-generated random numbers. Both groups received conventional medication and rehabilitation therapy. The experimental group received 4 weeks of 1 Hz rTMS treatment in the primary cortical motor area (M1) of the healthy side, with the treatment coil tangent to the skull surface; the sham stimulation group underwent the same procedures as the experimental group, but the treatment coil was perpendicular to the skull surface instead. Lower-extremity subscale of the Fugl-Meyer Assessment (FMA-LE), Berg Balance Scale (BBS), gait analysis, and lower-extremity surface electromyography (LESEM) were performed in both groups before and after rTMS treatment. Results: All 96 patients completed the test with no shedding and no adverse reactions. After treatment, the FMA-LE score and BBS score of the 2 groups of patients were significantly improved as compared with the pre-treatment (P &lt; 0.05), and the TUG test time was reduced as compared with the pre-treatment (P &lt; 0.05). The true stimulation group had greater improvement in all assessment indexes than that of the sham stimulation group (P &lt; 0.05). After treatment, the electromyographic activity of the tibialis anterior and rectus femoris muscles in the true simulation group improved significantly. The step length, step speed, and step frequency were also significantly improved in both groups after treatment, and the symmetrical ratio of step length and support time was reduced (P &lt; 0.05). Comparison between the groups revealed that the true simulation group significantly improved after rTMS treatment as compared to the sham stimulation group (P &lt; 0.05). Conclusion: 1Hz rTMS treatment safely and effectively improved motor and balance function in patients with post-stroke lower limb motor dysfunction.

Abstract TMP120: Contralesional Corticospinal Tract Reinnervates Cervical Spinal Anatomical Regions With Highest Pre-Lesion Synapse Density After Unilateral M1 Stroke in Mice

Introduction: Stroke leaves many patients with significant motor impairment. Following ischemic lesions of the rodent primary motor cortex, sprouting of the contralesional corticospinal tract (cCST) into the injured hemicord is associated with improved motor recovery. In adult mice, most corticospinal neurons project to spinal interneurons, and few synapse directly on alpha motor neurons. We examined the distribution of newly formed corticospinal synapses in the mouse spinal cord, using genetically encoded tracers, 3D microscopy, and a spinal atlas with machine learning-based automated classification and registration. Hypothesis: We tested the hypothesis that cCST neurons innervate homotopic regions in the injured hemicord after unilateral motor cortex stroke in adult mice. Method: We induced a photothrombotic motor cortex stroke or performed sham surgery (n=4 per group) in 8-11 week old male C57/B6 mice and administered a contralesional motor cortex injection of an anterograde adeno-associated virus expressing both membrane-targeted tdTomato and synaptically-targeted eGFP. Cervical spinal cords were subjected to volumetric imaging via serial two-photon tomography (TissueCyte 1000) to characterize synaptic and axonal density of cCST collaterals in whole cervical spinal cords in both stroke and sham mice. Unbiased, global quantification of axonal and synaptic density across the entire cervical cord was accomplished by the development of a custom automated image analysis pipeline, incorporating a novel 3D spinal cord reference volume, published spinal cord annotations comprising 47 distinct anatomical regions (SpinalJ), and machine learning based pixel classification. Results: We observed cCST synapses in the 6-week post-stroke injured hemicord innervating lamina IV &amp; IX most densely at C7 &amp; C8 (See Figure). Conclusions: Contralesional CST reinnervation of the denervated hemicord is targeted to both lamina and cervical level specific.

Abstract TP166: White Matter Hyperintensity Burden Associated With Stroke Severity, Aphasia, and Motor Deficits During Intracerebral Hemorrhage Hospitalization

Introduction: Cerebral Small Vessel Disease (CSVD) is associated with cognitive disruptions after intracerebral hemorrhage (ICH), however evidence connecting CSVD to specific neurological deficits after ICH is limited. Methods: Electronic medical record data were retrieved for adult patients (&gt;18 years) with admission for primary non-traumatic ICH, available admission NIHSS scores, and CSVD assessment. CSVD burden was graded from 0-4, with 1 point assessed for: 1) deep Fazekas white matter hyperintensity (WMH) score of 2-3 or periventricular (PV) Fazekas score of 3; 2) cerebral microbleed presence; 3) lacune presence; 4) &gt; 20 basal ganglia perivascular spaces. Severe CSVD was assessed scores ≥ 3, and individual marker severity was assessed using the same criteria. The primary outcome was moderate-severe stroke (total NIHSS score ≥5). Secondary outcomes were severe motor deficit (motor score &gt;12), complete aphasia (language score = 3), and cortical deficit (any impairment in language, extinction, and gaze). Associations between CSVD and NIHSS were determined using multivariable logistic regression, adjusting for major clinical and demographic factors. Adjusted odds ratios (aOR) and 95% confidence interval (CI) are reported. Results: The cohort included 1024 patients (median age [interquartile range]: 71 [61-79], 53% male). Patients were 22% Hispanic and had a racial distribution of 61% White, 24% Black, 8% Asian, 7% other. The median NIHSS score was 4 [1-11]; 477 (47%) showed moderate-severe NIHSS scores and 262 (26%) showed severe CSVD. Severe PV WMH burden was independently associated with moderate-severe NIHSS score (vs non-severe; aOR, 95% CI: 1.55, [1.02-2.36]). Severe deep WMH burden (vs non-severe) was independently associated with aphasia (1.97, [1.02-3.81]), and motor deficit (3.95, [1.22-12.73]) (Figure 1). Conclusion: Severe WMH burdens increase odds of neurological deficit among patients with primary ICH.

CTBS over primary motor cortex increased contralateral corticomuscular coupling and interhemispheric functional connection

Objective. Transcranial magnetic stimulation is a non-invasive brain stimulation technique that changes the activity of the cerebral cortex. Contralesional continuous theta burst stimulation (cTBS) has been proposed and verified beneficial to stroke motor recovery. However, the underlying mechanism is still unclear. Approach. 20 healthy right-handed subjects were recruited in this study, receiving real-cTBS over their left primary motor cortex or sham-cTBS. We designed the finger tapping task (FTT) before and after stimulation and recorded the accuracy and reaction time (RT) of the task. The electroencephalogram and surface electromyogram signals were recorded during the left finger pinching task (FPT) before and after stimulation. We calculated cortico-muscular coherence (CMC) in the contralateral hemisphere and cortico-cortical coherence (CCC) in the bilateral hemisphere. The two-way repeated measures analysis of variance was used to analyze the effect of cTBS. Main results. In the FTT, there was a significant main effect of ‘time’ on RT (F(1, 38) = 24.739, p < 0.001). In the FPT, the results showed that there was a significant interaction effect on the CMC peak and area in the beta band (peak: F(1, 38) = 8.562, p = 0.006; area: F(1, 38) = 5.273, p = 0.027), on the CCC peak in the alpha band (F(1, 38) = 4.815, p = 0.034) and area in the beta band (F(1, 38) = 4.822, p= 0.034). The post hoc tests showed that the CMC peak (W = 20, p = 0.002), the CMC area (W = 13, p = 0.003) and the CCC peak (t = −2.696, p = 0.014) increased significantly after real-cTBS. However, there was no significant decrease or increase after sham-cTBS. Significance. Our study found that cTBS can improve CMC of contralateral hemisphere and CCC of bilateral hemisphere, indicating that cTBS can strengthen cortico-muscular and cortico-cortical coupling.

Effects of anodal tDCS on resting state eeg power and motor function in acute stroke: a randomized controlled trial

BackgroundAnodal transcranial direct current stimulation (tDCS) is a beneficial adjunctive tool in stroke rehabilitation. However, only a few studies have investigated its effects on acute stroke and recruited only individuals with mild motor deficits. This study investigated the effect of five consecutive sessions of anodal tDCS and conventional physical therapy on brain activity and motor outcomes in individuals with acute stroke, with low and high motor impairments.MethodsThirty participants were recruited and randomly allocated to either the anodal or sham tDCS group. Five consecutive sessions of tDCS (1.5 mA anodal or sham tDCS for 20 min) were administered, followed by conventional physical therapy. Electroencephalography (EEG), Fugl-Meyer Motor Assessment (FMA), and Wolf Motor Function Test (WMFT) were performed at pre-, post-intervention (day 5), and 1-month follow-up. Sub-analyses were performed on participants with low and high motor impairments. The relationship between EEG power and changes in motor functions was assessed.ResultsLinear regression showed a significant positive correlation between beta bands and the FMA score in the anodal group. Elevated high frequency bands (alpha and beta) were observed at post-intervention and follow-up in all areas of both hemispheres in the anodal group, while only in the posterior area of the non-lesioned hemisphere in the sham group; however, such elevation induced by tDCS was not greater than sham. Lower limb function assessed by FMA was improved in the anodal group compared with the sham group at post-intervention and follow-up only in those with low motor impairment. For the upper limb outcomes, no difference between groups was found.ConclusionsFive consecutive days of anodal tDCS and physical therapy in acute stroke did not result in a superior improvement of beta bands that commonly related to stroke recovery over sham, but improved lower extremity functions with a post-effect at 1-month follow-up in low motor impairment participants. The increase of beta bands in the lesioned brain in the anodal group was associated with improvement in lower limb function.Trial registration: NCT04578080, date of first registration 10/01/2020.

Data-driven biomarkers better associate with stroke motor outcomes than theory-based biomarkers.

Chronic motor impairments are a leading cause of disability after stroke. Previous studies have associated motor outcomes with the degree of damage to predefined structures in the motor system, such as the corticospinal tract. However, such theory-based approaches may not take full advantage of the information contained in clinical imaging data. The present study uses data-driven approaches to model chronic motor outcomes after stroke and compares the accuracy of these associations to previously-identified theory-based biomarkers. Using a cross-validation framework, regression models were trained using lesion masks and motor outcomes data from 789 stroke patients from the Enhancing NeuroImaging Genetics through Meta Analysis (ENIGMA) Stroke Recovery Working Group. Using the explained variance metric to measure the strength of the association between chronic motor outcomes and imaging biomarkers, we compared theory-based biomarkers, like lesion load to known motor tracts, to three data-driven biomarkers: lesion load of lesion-behaviour maps, lesion load of structural networks associated with lesion-behaviour maps, and measures of regional structural disconnection. In general, data-driven biomarkers had stronger associations with chronic motor outcomes accuracy than theory-based biomarkers. Data-driven models of regional structural disconnection performed the best of all models tested (R 2 = 0.210, P < 0.001), performing significantly better than the theory-based biomarkers of lesion load of the corticospinal tract (R 2 = 0.132, P < 0.001) and of multiple descending motor tracts (R 2 = 0.180, P < 0.001). They also performed slightly, but significantly, better than other data-driven biomarkers including lesion load of lesion-behaviour maps (R 2 = 0.200, P < 0.001) and lesion load of structural networks associated with lesion-behaviour maps (R 2 = 0.167, P < 0.001). Ensemble models - combining basic demographic variables like age, sex, and time since stroke - improved the strength of associations for theory-based and data-driven biomarkers. Combining both theory-based and data-driven biomarkers with demographic variables improved predictions, and the best ensemble model achieved R 2 = 0.241, P < 0.001. Overall, these results demonstrate that out-of-sample associations between chronic motor outcomes and data-driven imaging features, particularly when lesion data is represented in terms of structural disconnection, are stronger than associations between chronic motor outcomes and theory-based biomarkers. However, combining both theory-based and data-driven models provides the most robust associations.

Update on Non-invasive Brain Stimulation on Stroke Motor Impairment: A Narrative Review.

Stroke is a leading global cause of death and disability, with motor impairment being one of the common post-stroke complications. Rehabilitation is crucial for functional recovery. Recently, non-invasive brain stimulation (NIBS) has emerged as a promising intervention that allows neuromodulation by activating or inhibiting neural activity in specific brain regions. This narrative review aims to examine current research on the effects of various NIBS techniques, including repetitive transcranial magnetic stimulation, transcranial direct current stimulation, vagus nerve stimulation, and transcranial focused ultrasound on post-stroke motor function.

Neurobiomechanical mechanism of Tai Chi to improve upper limb coordination function in post-stroke patients: a study protocol for a randomized controlled trial

BackgroundUpper limb dysfunction seriously affects the ability of stroke patients to perform activities of daily living. As a popular exercise therapy, Tai Chi may become an alternative intervention. However, the neurophysiological mechanism by which Tai Chi improves upper limb dysfunction in stroke patients is still unclear, which limits its further promotion and application. Therefore, conducting a strict randomized clinical trial is necessary to observe how Tai Chi affects upper limb dysfunction in stroke patients and to explore its neurophysiological mechanism.Methods/designThis report describes a randomized, parallel-controlled trial with distributive concealment and evaluator blinding. A total of 84 eligible participants will be randomly assigned to the Tai Chi group or the control group in a 1:1 ratio. The participants in the Tai Chi group will receive 4 weeks of Tai Chi training: five 60-min sessions a week for a total of 20 sessions. The participants in the control group will not receive Tai Chi training. Both groups will receive medical treatment and routine rehabilitation training. The primary outcome measure is the mean change in the Fugl-Meyer Assessment Upper Extremity (FMA-UE) scale score between baseline and 4 weeks; the secondary outcomes are the mean changes in kinematic characteristics and the Wolf Motor Function Test (WMFT) and Stroke Impact Scale (SIS) scores. In addition, the corticomuscular coupling level and near-infrared brain functional imaging will be monitored to explore the mechanism by which Tai Chi improves upper limb function of stroke patients.DiscussionThis randomized controlled trial will examine the effectiveness of Tai Chi in stroke patients with upper limb dysfunction and explore the neurophysiological mechanism. Positive results will verify that Tai Chi can improve upper limb function of stroke patients.Trial registrationChinese Clinical Trial Registration Center, ChiCTR2200061376 (retrospectively registered). Registered June 22, 2022. http://www.chictr.org.cn/listbycreater.aspx. Manuscript Version: 3.0 Manuscript Date: October 10, 2023.

Dance after stroke improves motor recovery in the subacute phase: A randomized controlled trial

PurposeThe objective of this study was to investigate the effects of a dance program, combined with conventional treatments, on the motor recovery and quality of life of stroke survivors in comparison with conventional treatments alone. Materials and methodsA total of 16 subacute stroke survivors were randomized into two groups: a dance group (DG) and a conventional treatments group (CG). Stroke severity, cognitive abilities, and motor capacities were assessed at baseline. For six weeks, all participants underwent standard rehabilitation. However, in the DG, participants attended an additional weekly dance class. In both groups, the Mini-BESTest, Functional Independence Measure (FIM), ABC-Scale, Lower Extremity Motor Coordination Test (LEMOCOT), quadriceps strength, and Stroke-Specific Quality of Life Scale (SS-QOL) were measured at weeks 4 and 6. Nonparametric statistical tests were applied. ResultsCompared to the CG, the DG significantly improved recovery of balance, coordination, and FIM after four or six weeks. No differences were observed for quadriceps strength, SS-QOL, or cognition. Participants were completely satisfied with the dance class, and no adverse effects were observed. ConclusionsThis study was discontinued following the COVID-19 health crisis. However, the analysis revealed numerous beneficial effects of dance practice for subacute stroke survivors. The results contribute significantly to the advancement of artistic practices in stroke rehabilitation.

Alterations of dynamic and static brain functional activities and integration in stroke patients

ObjectiveThe study aimed to investigate the comprehensive characteristics of brain functional activity and integration in patients with subcortical stroke using dynamic and static analysis methods and to examine whether alterations in brain functional activity and integration were associated with clinical symptoms of patients.MethodsDynamic amplitude of low-frequency fluctuation (dALFF), static amplitude of low-frequency fluctuation (sALFF), dynamic degree centrality (dDC), and static degree centrality (sDC) were calculated for 19 patients with right subcortical stroke, 16 patients with left subcortical stroke, and 25 healthy controls (HC). Furthermore, correlation analysis was performed to investigate the relationships between changes in brain functional measurements of patients and clinical variables.ResultsGroup comparison results showed that significantly decreased dALFF in the left angular (ANG_L) and right inferior parietal gyrus (IPG_R), decreased sALFF in the left precuneus (PCUN_L), and decreased sDC in the left crus II of cerebellar hemisphere (CERCRU2_L) and IPG_R, while significantly increased sDC in the right lobule X of cerebellar hemisphere (CER10_R) were detected in patients with right subcortical stroke relative to HC. Patients with left subcortical stroke showed significantly decreased sALFF in the left precuneus (PCUN_L) but increased sDC in the right hippocampus (HIP_R) compared with HC. Additionally, the altered sDC values in the CER10_R of patients with right subcortical stroke and in the HIP_R of patients with left subcortical stroke were associated with the severity of stroke and lower extremities motor function. A correlation was also found between the altered sALFF values in the PCUN_L of patients with left subcortical stroke and lower extremities motor function.ConclusionThese findings suggest that time-varying brain activity analysis may supply complementary information for static brain activity analysis. Dynamic and static brain functional activity and integration analysis may contribute to a more comprehensive understanding of the underlying neuropathology of dysfunction in stroke patients.