The interaction between training and plasticity in the poststroke brain

A randomized controlled trial of timing and dosage of upper extremity rehabilitation in virtual environments in persons with subacute stroke

Many people with stroke experience incomplete recoveries, leaving them with upper extremity (UE) deficits affecting their long-term independence. Interventions including virtual reality (VR) and robotics have been developed to foster neuroplasticity post stroke. Few of the many studies examining these interventions consider the impact of both timing and dosage. The primary aim of this randomized controlled trial was to investigate (1) dosage and (2) timing of UE VR/robotic training in the subacute period post stroke. 100 participants were consented 5-30 days after stroke. They were randomized to an Early (first month) or Delayed (second month) VR/robotic group (EVR/DVR), a dose matched usual care group (DMUC) or a usual care group (UC). Participants were evaluated using impairment, motor function, and quality of life measures immediately before, after, and 1 month after training, and 4 and 6 months post stroke. At 4 months post stroke the DVR group showed a higher rate of change from baseline on the Action Research Arm Test compared to the EVR group. This difference was not sustained; none of the training groups demonstrated significantly better scores on any outcome measure 6 months post stroke. Growth mixture modeling revealed three groups with patterns of recovery associated with early finger movement. At 6 months post stroke, the EuroQol was moderately correlated with impairment and activity.

Reinforcement Learning is Impaired in the Sub-acute Post-stroke Period

BACKGROUND

In humans, most spontaneous recovery from motor impairment after stroke occurs in the first 3 months. Studies in animal models show higher responsiveness to training over a similar time-period. Both phenomena are often attributed to a milieu of heightened plasticity, which may share some mechanistic overlap with plasticity associated with normal motor learning.

OBJECTIVE

Given that neurorehabilitation approaches are frequently predicated on motor learning principles, here we asked if the sensitivity of trial-to-trial learning for 2 kinds of motor learning processes often involved during rehabilitation is also enhanced early post-stroke. In a cross-sectional design, we compared (1) reinforcement and (2) error-based learning in 2 groups: 1 tested within 3 months after stroke (early group, N = 35) another tested more than 6 months after stroke (late group, N = 30). These 2 forms of motor learning were assessed with variations of the same visuomotor rotation task. Critically, motor execution was matched between the 2 groups.

RESULTS

Reinforcement learning was impaired in the early but not the late group, whereas error-based learning was unimpaired in either group. These findings could not be attributed to differences in baseline execution, cognitive impairment, gender, age, or lesion volume and location.

DISCUSSION

The presence of a deficit in reinforcement motor learning in the first 3 months after stroke has important implications for rehabilitation.

CONCLUSION

It might be necessary to either increase reinforcement feedback given early after stroke, increase the dose of rehabilitation to compensate, or delay onset of rehabilitation approaches that may rely on reinforcement, for example, constraint-induced movement therapy, and instead emphasize other forms of motor training in the subacute time period.

Effects of very early exercise on inflammatory markers and clinical outcomes in patients with ischaemic stroke- a randomized controlled trial

BACKGROUND

Apart from the limited evidence of the effects of very early exercise (VEE) on clinical outcomes (COs) in stroke, better knowledge is required to understand the cellular action induced by VEE. This study investigated the effects of VEE on inflammatory markers (IMs) and COs. It further evaluated the association between acute changes in IMs and COs at follow-up in individuals with first-ever mild-to-moderate ischaemic stroke.

METHODS

A prospective, single-center, single-blind, randomized controlled trial (retrospectively registered: PACTR202406755848901; 10-06-2024) was conducted. Forty-eight patients randomized (1:1) into the VEE group (VEEG) and usual care group (UCG) completed the follow-up. Within 24 h of stroke onset, patients in VEEG underwent 45 min of VEE twice daily, amounting to 1.5 h/d, for seven days while patients in UCG received regular turning and positioning. The levels of IMs including interleukin-6 (IL-6), fibrinogen, leucocytes, neutrophils, lymphocytes, and monocytes were assessed at baseline, 4th, and 7th day for both groups. Thereafter, each patient received 90-min follow-up physiotherapy twice weekly for three months. Motor impairment, physical disability, functional independence, anxiety, depression, and cognition were evaluated at 1st and 3rd month of follow-up.

RESULTS

On the 4th and 7th day, patients in VEEG show trends of lower levels of IL-6, leucocytes, neutrophils, and monocytes and higher levels of lymphocytes. However, a non-linear effect of VEE on plasma fibrinogen was observed compared to UC. Furthermore, better improvement in motor impairment, physical disability, functional independence, anxiety, depression, and cognition were observed in VEEG. The positive modulation of IMs by VEE was associated with COs over time, including associations between changes in IL-6 at days 4 and 7 and 3-month functional independence (rs = -0.33; p = 0.019; rs = -0.33; p = 0.021), and at day 7 and 3-month motor impairment (rs = 0.30; p = 0.039).

CONCLUSIONS

Initiating moderate-intensity exercise within 24 h appears beneficial in positively modulating IMs, including IL-6, at the acute stage and improving the physical, motor, cognitive, and affective functions at 1-and 3-month follow-up. The association between exercise-induced acute changes in IMs and improved COs over time highlights the potential role of moderate-intensity VEE in enhancing stroke recovery through positive inflammatory modulation.

Inferior vena cava filter migration to the heart after stroke: a case report

This case report discusses the functional outcomes and multidisciplinary coordination of care for a patient with hemiplegia due to stroke complicated by a migrated inferior vena cava (IVC) filter embedded in the right side of the heart. The patient suffered an acute right-sided stroke with hemorrhagic transformation requiring hemicraniectomy with left hemiplegia. The patient developed a subsequent pulmonary embolism requiring IVC filter placement as anticoagulation was contraindicated due to risk of further intracranial hemorrhage. The IVC filter was later identified bridging the tricuspid valve, and surgical intervention was contraindicated requiring a coordinated plan to delay surgical removal of the filter in order to allow for optimization of the patient's functional and medical status. The patient underwent extensive telemetry monitoring in the intensive care unit to verify no significant cardiac arrhythmia developed with physical activity and was ultimately cleared for admission to acute inpatient rehabilitation. There was a well-coordinated effort between the cardiac, surgical, intensive care, and rehabilitation teams to transition to the inpatient rehabilitation facility to minimize risk and enhance recovery. The patient demonstrated functional improvement throughout rehabilitation and was discharged home with family with eventual surgical removal of the IVC filter. This case highlights the importance of collaboration across multiple disciplines to maximize patient rehabilitation and function, particularly in the context of atypical complications.

A novel TMS framework for assessing neurophysiological recovery at the subacute stage after stroke

OBJECTIVE

To use peri-threshold transcranial magnetic stimulation (TMS) intensities to elicit motor evoked potentials (MEPs) during the subacute stage after stroke and assess their association with upper limb motor recovery.

METHODS

Twenty-five MEP+ patients participated in three sessions at 1, 3, and 6 months post-stroke. Single-pulse TMS across a range of stimulation intensities was used to elicit MEPs in four muscles of the paretic and non-paretic upper limb. At each timepoint, threshold matrices were constructed based on MEP amplitude and persistence. A matrix element was suprathreshold if five out of ten stimulations elicited MEPs ≥ 50 μV. A subthreshold element produced MEPs below this criterion. Dexterity was assessed using the nine hole peg test.

RESULTS

There were fewer suprathreshold, and more subthreshold elements on the paretic compared to the non-paretic side. The number of suprathreshold elements on the paretic side increased between 1 and 6 months post-stroke. Neither sub- nor supra-threshold elements were associated with dexterity recovery.

CONCLUSION

The proportion of sub- and supra-threshold elements reflect neurophysiological recovery during the subacute stage after stroke. A threshold matrix framework can identify patients with stable versus dynamic neurophysiology post-stroke.

SIGNIFICANCE

A compositional analysis framework can quantify neurophysiological recovery after stroke.

Experience-driven competition in neural reorganization after stroke

Behavioural experiences interact with regenerative responses to shape patterns of neural reorganization after stroke. This review is focused on the competitive nature of these behavioural experience effects. Interactions between learning-related plasticity and regenerative reactions have been found to underlie the establishment of new compensatory behaviours and the efficacy of motor rehabilitative training in rodent stroke models. Learning in intact brains depends on competitive and cooperative mechanisms of synaptic plasticity. Synapses are added in response to learning and selectively maintained and strengthened via activity-dependent competition. Long-term memories for experiences that occur closely in time can be weakened or enhanced by competitive or cooperative interactions in the time-dependent process of stabilizing synaptic changes. Rodent stroke model findings suggest that compensatory reliance on the non-paretic hand after stroke can shape and stabilize synaptic reorganization patterns in both hemispheres, to compete with the capacity for experiences of the paretic side to do so. However, the competitive edge of the non-paretic side can be countered by overlapping experiences of the paretic hand, and might even be shifted in a cooperative direction with skilfully coordinated bimanual experience. Advances in the basic understanding of learning-related synaptic competition are helping to inform the basis of experience-dependent variations in stroke outcome.

Coordinated human-exoskeleton locomotion emerges from regulating virtual energy

Lower-limb exoskeletons have demonstrated great potential for gait rehabilitation in individuals with motor impairments; however, maintaining human-exoskeleton coordination remains a challenge. The coordination problem, referred to as any mismatch or asynchrony between the user's intended trajectories and exoskeleton desired trajectories, leads to sub-optimal gait performance, particularly for individuals with residual motor ability. Here, we investigate the virtual energy regulator (VER)'s ability to generate coordinated locomotion in lower limb exoskeleton. Contribution: (1) In this paper, we experimented VER on a group of nine healthy individuals at different speeds (0.6m/s - 0.85m/s) to study the resultant gait coordination and naturalness on a large group of users. (2) The resultant assisted gait is compared to the natural and passive (zero-torque exoskeleton) walking conditions in terms of muscle activities, kinematic, spatiotemporal and kinetic measures, and questionnaires. (3) Moreover, we presented the VER's convergence proof considering the user contribution to the gait and introduced a metric to measure the user's contribution to gait. (4) We also compared VER performance with the phase-based path controller in terms of muscle effort reduction and joint kinematics using three able-bodied individuals. Results: (1) The results from the VER demonstrate the emergence of natural, coordinated locomotion, resulting in an average muscle effort reduction ranging from 13.1% to 17.7% at different speeds compared to passive walking. (2) The results from VER revealed improvements in all indicators towards natural gait when compared to walking with a zero-torque exoskeleton, for instance, an enhancement in average knee extension ranging from 3.9 to 4.1 degrees. All indicators suggest that the VER preserves natural gait variability and user engagement in locomotion control. (3) Using VER also yields in 13.9%, 15.1%, and 7.0% average muscle effort reduction when compared to the phase-based path controller. (4) Finally, using our proposed metric, we demonstrated that the resultant locomotion limit cycle is a linear combination of human-intended limit cycle and the VER's limit cycle. These findings may have implications for understanding how the central nervous system controls our locomotion.

Early changes in spatiotemporal dynamics of remapped circuits and global networks predict functional recovery after stroke in mice

Significance

Stroke is the leading cause of chronic disability in the United States. How stroke size affects post-stroke repair and recovery is poorly understood.

Aim

We aim to investigate the effects of stroke size on early repair patterns and determine how early changes in neuronal circuits and networks predict functional outcomes after stroke.

Approach

We used wide-field optical imaging, photothrombosis, and the cylinder-rearing assay to examine changes in neuronal circuit and network activity in the context of functional recovery after stroke.

Results

Larger strokes ablating S 1 FP caused diffuse and widespread forepaw stimulus-evoked cortical activation, including contralesional regions evolving within 4 weeks post-stroke; smaller strokes resulted in more focused ipsilesional activation. Larger strokes decreased neuronal fidelity and bilateral coherence during stimulation of either the affected or unaffected forepaw within this 4-week period. Mice in the larger lesion group demonstrated hyperconnectivity within the contralesional hemisphere at the resting state. Greater degrees of remapping diffusivity, neuronal fidelity degradation, and hyperconnectivity predicted worse 8-week recovery after statistically controlling for the effect of infarct size.

Conclusions

These results suggest that diffuse patterns of remapping, and desynchronization and hyperconnectivity of cortical networks, evolving early after stroke may reflect maladaptive plasticity, predicting poor long-term functional recovery.

Cognitive-motor dual-task training on gait and balance in stroke patients: meta-analytic report and trial sequential analysis of randomized clinical trials

OBJECTIVE

Cognitive-motor dual-tasking training (CMDT) might improve limb function and motor performance in stroke patients. However, is there enough evidence to prove that it is more effective compared with conventional physical single-task training? This meta-analysis and Trial Sequential Analysis of randomized clinical trials (RCTs) aimed to evaluate the effectiveness of CMDT on balance and gait for treating hemiplegic stroke patients.

METHODS

The databases were searched in PubMed, Web of Science, Ovid Database and The Cochrane Library, SinoMed database, Chinese National Knowledge Infrastructure (CNKI), Wan Fang database, and VIP database up to December 8, 2023. The Cochrane-recommended risk of bias (RoB) 2.0 tool was employed to assess risk of bias in trials. The statistical analysis was employed using R version 4.3.2. In addition, subgroup analyses and meta-regression were performed to explore the possible sources of heterogeneity. The evidence for each outcome was evaluated according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria. The Copenhagen Trial Unit's Trial Sequential Analysis (version 0.9.5.10 Beta) was used for sequential analysis.

RESULTS

Seventeen randomized clinical trials (RCTs) (n = 751 patients) were included. The results demonstrated that cognitive-motor dual-task training (CMDT) might be beneficial on stroke patients on Berg Balance Scale (BBS) (MD = 4.26, 95% CI 1.82, 6.69, p < 0.0001) (low-quality evidence). However, CMDT might not affect Time Up and Go test (TUG) (MD = -1.28, 95% CI -3.63, 1.06, p = 0.284); and single-task walking speed (MD = 1.35, 95% CI -1.56, 4.27, p = 0.413) in stroke patients (low-quality evidence). The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) results indicated that all findings were very low to low certainty. Trial Sequential Analyses demonstrated larger sample sizes are required for confirming our findings.

CONCLUSION

Cognitive-motor dual-task training (CMDT) compared with conventional physical single-task training might be an effective intervention for improving static balance function in stroke patients (low-quality evidence), which should be interpreted cautiously due to heterogeneity and potential biases. Nevertheless, further research is required to support the abovementioned findings. Trial Registration This protocol was registered in PROSPERO (CRD42023490530).

The Role of Mirror Therapy in the Rehabilitation of the Upper Limb's Motor Deficits After Stroke: Narrative Review

Stroke is one of the leading causes of death and disability worldwide and poses a tremendous socioeconomic burden upon individuals, countries and healthcare systems. It causes debilitating symptoms and thus interferes with many aspects of the patient's life, including physical functioning, cognition, emotional status, activities of daily living, social reintegration and quality of life. Post-stroke patients frequently experience functional motor disabilities of the upper limb, which restrict autonomy and self-efficacy and cause limitations in engagement with activities and social participation, as well as difficulties in performing important occupations. It is therefore not surprising that motor impairment or loss of motor function of the upper limb is one of the most devastating sequelae of stroke. On these grounds, achieving optimal functioning of the upper limb after stroke remains a fundamental goal of stroke rehabilitation. Mirror therapy (MT) represents one of the several rehabilitation techniques used for restoring the upper limb's motor function after a stroke. However, conflicting results about the role of MT in the rehabilitation of the upper limb's motor deficits have been reported in the literature. Accordingly, the aim of this narrative review is to summarize existing evidence regarding the effects of MT on the upper limb's motor function in post-stroke patients and to further explore its role when applied in different phases of stroke.

The Excessive Tonic Inhibition of the Peri-infarct Cortex Depresses Low Gamma Rhythm Power During Poststroke Recovery

The cortex immediately surrounding a brain ischemic lesion, the peri-infarct cortex (PIC), harbors a large part of the potential to recover lost functions. However, our understanding of the neurophysiological conditions in which synaptic plasticity operates remains limited. Here we hypothesized that the chronic imbalance between excitation and inhibition of the PIC prevents the normalization of the gamma rhythm, a waveband of neural oscillations thought to orchestrate action potential trafficking. Probing the local field potential activity of the forelimb primary sensory cortex (S1FL) located in the PIC of male adult mice, we found a constant, deep reduction of low-gamma oscillation power (L-gamma; 30-50 Hz) precisely during the critical time window for recovery (1-3 weeks after stroke). The collapse of L-gamma power negatively correlated with behavioral progress in affected forelimb use. Mapping astrocyte reactivity and GABA-like immunoreactivity in the PIC revealed a parallel high signal, which gradually increased when approaching the lesion. Increasing tonic inhibition with local infusion of GABA or by blocking its recapture reduced L-gamma oscillation power in a magnitude similar to stroke. Conversely, the negative allosteric modulation of tonic GABA conductance using L655,708 or the gliopeptide ODN rescued the L-gamma power of the PIC. Altogether the present data point out that the chronic excess of ambient GABA in the PIC limits the generation of L-gamma oscillations in the repairing cortex and suggests that rehabilitative interventions aimed at normalizing low-gamma power within the critical period of stroke recovery could optimize the restitution of lost functions.

tDCS does not add effect to foot drop stimulator and gait training in improving clinical parameters and neuroplasticity biomarkers in chronic post-stroke: randomized controlled trial

BACKGROUND

Transcranial direct current stimulation (tDCS) and foot drop stimulators (FDS) are widely used for stroke rehabilitation. However, no study has investigated if tDCS could boost the effects of FDS and gait training in improving clinical parameters and neuroplasticity biomarkers of chronic post-stroke subjects.

OBJECTIVE

To investigate the effects of combining tDCS and FDS on motor impairment, functional mobility, and brain-derived neurotrophic factor (BDNF) serum levels. Also, to evaluate the effects of this protocol on the insulin-like growth factor-1 (IGF-1), insulin growth factor-binding proteins-3 (IGFBP-3), interleukin (IL) 6 and 10, and tumor necrosis factor-α (TNF-α) levels.

METHODS

Thirty-two chronic post-stroke individuals were randomized to tDCS plus FDS or sham tDCS plus FDS groups. Both groups underwent ten gait training sessions for two weeks using a FDS device and real or sham tDCS. Blood samples and clinical data were acquired before and after the intervention. Motor impairment was assessed by the Fugl-Meyer Assessment and functional mobility using the Timed up and Go test.

RESULTS

Both groups improved the motor impairment and functional mobility and increased the BDNF levels. Both groups also increased the IL-10 and decreased the cortisol, IL-6, and TNF-α levels. No difference was observed between groups.

CONCLUSION

tDCS did not add effect to FDS and gait training in improving clinical parameters and neuroplasticity biomarkers in chronic post-stroke individuals. Only FDS and gait training might be enough for people with chronic stroke to modify some clinical parameters and neuroplasticity biomarkers.

Longitudinal associations between stroke-related neurologic deficits and course of basic activities of daily living up to six months after stroke

PURPOSE

To investigate the course of basic activities of daily living (ADL) from admission up to six months after the stroke and the longitudinal associations between stroke-related neurological deficits at admission to the stroke unit and course of basic ADL.

MATERIALS AND METHODS

180 individuals with a first-ever stroke were assessed at admission to the stroke unit and at follow-ups of three and six months. Stroke-related neurological deficits were assessed at admission with the National Institutes of Stroke Scale (NIHSS). Independence in basic ADL was assessed at admission and three and six months after the stroke by the Modified Barthel Index (MBI). Generalized Estimating Equations (GEE) were performed.

RESULTS

Dependence in basic ADL reduced overtime, with most changes occurring over the first three months. Individuals, who had moderate/severe stroke-related neurological deficits (NIHSS ≥6) at admission, had higher chances of becoming more dependent in activities related to feeding (OR:1.27;95%CI = 1.03-1.55;p = 0.021), bathing (OR:1.30;95%CI = 1.11-1.50;p = 0.0005), dressing (OR:1.19;95%CI = 1.04-1.36;p = 0.010), transfers (OR:1.24;95%CI = 1.05-1.46;p = 0.0072), stair climbing (OR:1.46;95%CI = 1.27-1.66;p < 0.0001), and ambulation (OR:1.21;95%CI = 1.02-1.43;p < 0.0001).

CONCLUSIONS

Decreases in dependence in basic ADL occurred mainly over three months after the stroke and showed different patterns for specific ADL. Baseline moderate/severe stroke-related neurological deficits were associated with poor functional status in basic ADL over the follow-up period.

Longitudinal Changes in Factors Associated with Walking Independence at Hospital Discharge in Patients with Stroke: A Retrospective Study

Background/Objectives: Patients with stroke usually have long-term residual gait disability. However, temporal changes in factors associated with gait independence in these patients at the time of hospital discharge have not been clarified. This study aimed to determine changes over time in factors associated with gait independence in patients with stroke at the time of hospital discharge. This would predict that factors associated with the level of walking independence in patients with stroke at discharge from the hospital would show different results depending on the changes over time post-stroke onset. Methods: This retrospective observational study used data from the medical records of patients with stroke with unilateral supratentorial lesions who were admitted and rehabilitated at Tesseikai Neurosurgical Hospital between October 2020 and July 2024. The Functional Ambulation Category (FAC), Stroke Impairment Assessment Set-lower extremity motor items, Trunk Control Test, Mini-Balance Evaluation Systems Test (Mini-BESTest), and Functional Independence Measure cognitive items were assessed monthly for 3 months post-stroke onset. Participants were classified into independent and non-independent walking groups using the FAC. Logistic regression analysis was performed with walking independence at discharge and other assessment indicators as the dependent and independent variables, respectively, to identify factors influencing walking independence at discharge. Independent variables were entered by month from 1 to 3 months. Results: Logistic regression analysis revealed that Mini-BESTest scores at 2 and 3 months post-stroke onset were significantly associated with walking independence at discharge (p < 0.05). Conclusions: This study suggests the importance of assessing the Mini-BESTest scores over time, starting at 2 months post-stroke onset, when determining walking independence in patients with stroke. Providing balance training to patients with low Mini-BESTest scores between 1 and 3 months post-stroke onset may contribute to improved walking independence at discharge.

Motor cortex is responsible for motoric dynamics in striatum and the execution of both skilled and unskilled actions

Striatum and its predominant input, motor cortex, are responsible for the selection and performance of purposive movement, but how their interaction guides these processes is not understood. To establish its neural and behavioral contributions, we bilaterally lesioned motor cortex and recorded striatal activity and reaching performance daily, capturing the lesion's direct ramifications within hours of the intervention. We observed reaching impairment and an absence of striatal motoric activity following lesion of motor cortex, but not parietal cortex control lesions. Although some aspects of performance began to recover after 8-10 days, striatal projection and interneuronal dynamics did not-eventually entering a non-motor encoding state that aligned with persisting kinematic control deficits. Lesioned mice also exhibited a profound inability to switch motor plans while locomoting, reminiscent of clinical freezing of gait (FOG). Our results demonstrate the necessity of motor cortex in generating trained and untrained actions as well as striatal motoric dynamics.

Enriched music-supported therapy for individuals with chronic stroke: a randomized controlled trial

OBJECTIVE

Many stroke survivors still present with upper-limb paresis six months post-stroke, impacting their autonomy and quality of life (QoL). We designed an enriched Music-supported Therapy (eMST) program to reduce disability in this population. We evaluated the eMST's effectiveness in improving functional abilities and QoL in chronic stroke individuals compared to the conventional motor program Graded Repetitive Arm Supplementary Program (GRASP).

METHODS

We conducted a pragmatic two-arm parallel-group randomized controlled trial with a 3-month follow-up and masked assessment. The eMST involved playing instruments during individual self-administered and group music therapy sessions. The GRASP consisted of self-administered motor exercises using daily objects. Both interventions were completed at home with telemonitoring and involved four one-hour weekly sessions for 10 weeks. The primary outcome was upper-limb motor function measured with the Action Research Arm Test. Secondary outcomes included motor impairment, daily life motor performance, cognitive functions, emotional well-being, QoL, self-regulation, and self-efficacy. Intention-to-treat (ITT) and per-protocol (PP) analyses were conducted including participants who discontinued the intervention and those who completed it entirely, respectively.

RESULTS

Fifty-eight chronic stroke patients were randomized to the eMST-group (n = 26; age: 64.2 ± 12.5; 6 [23.1%] females; 2.8 ± 2.9 years post-stroke), and the control group (n = 32; age: 62.2 ± 12; 8 [25%] females; 1.8 ± 6.2 years post-stroke). The eMST-group had more participants achieving a clinically relevant improvement in motor impairment post-intervention than the control group for the ITT (55% vs 21.6%; OR = 4.5 (95% CI 1.4-14); p = .019) and PP analyses (60% vs 20%; OR = 6 (95% CI 1.5-24.7); p = .024), sustained at follow-up. The eMST-group reported greater improvements in emotion (difference = 11.1 (95% CI 0.8-21.5; p = 0.36) and participation (difference = 10.3 (95% CI 0.6-25.9); p = 0.41) subscales of QoL, and higher enjoyment during the sessions (difference = 1 (95% CI 0.3-1.5); p = 0.12). No changes were found in other outcomes.

CONCLUSION

eMST demonstrated superiority over conventional motor rehabilitation program in enhancing upper-limb functions and QoL in chronic stroke individuals.

TRIAL REGISTRATION

ClinicalTrials.gov (ID: NCT04507542).

A Scoping Review of Technology-Based Approaches for Upper Limb Motor Rehabilitation after Stroke: Are We Really Targeting Severe Impairment?

Technology-based approaches for upper limb (UL) motor rehabilitation after stroke are mostly designed for severely affected patients to increase their recovery chances. However, the available randomized controlled trials (RCTs) focused on the efficacy of technology-based interventions often include patients with a wide range of motor impairment. This scoping review aims at overviewing the actual severity of stroke patients enrolled in RCTs that claim to specifically address UL severe motor impairment. The literature search was conducted on the Scopus and PubMed databases and included articles from 2008 to May 2024, specifically RCTs investigating the impact of technology-based interventions on UL motor functional recovery after stroke. Forty-eight studies were selected. They showed that, upon patients' enrollment, the values of the UL Fugl-Meyer Assessment and Action Research Arm Test covered the whole range of both scales, thus revealing the non-selective inclusion of severely impaired patients. Heterogeneity in terms of numerosity, characteristics of enrolled patients, trial design, implementation, and reporting was present across the studies. No clear difference in the severity of the included patients according to the intervention type was found. Patient stratification upon enrollment is crucial to best direct resources to those patients who will benefit the most from a given technology-assisted approach (personalized rehabilitation).

Effect of short-term 10 Hz repeated transcranial magnetic stimulation on postural control ability in patients with mild hemiparesis in acute ischemic stroke: a single-blinded randomized controlled trial

Background

Previous studies have demonstrated that repetitive transcranial magnetic stimulation (rTMS) can improve postural control in subacute and chronic ischemic stroke, but further research is needed to investigate the effect of rTMS on acute ischemic stroke.

Objective

We compared the therapeutic effects of rTMS plus conventional rehabilitation and conventional rehabilitation on postural control in patients with mild hemiparesis in acute ischemic stroke.

Methods

Eighty-six patients with acute ischemic stroke were randomly assigned to either the experimental group or the control group within 1-7 days of onset. Patients in both groups received conventional rehabilitation for 2 weeks. Patients in the experimental group received rTMS treatments lasting for 2 weeks. Before and after the 2-week treatment, patients were assessed based on the Timed up and Go (TUG) test, Dual-Task Walking (DTW) test, Functional Ambulation Category (FAC), Tinetti Performance Oriented Mobility Assessment (POMA), gait kinematic parameters, Barthel Index (BI), Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), and National Institutes of Health Stroke Scale (NIHSS). Additionally, TUG and single-task gait velocity were assessed at 2 months after the start of treatment, and independent walking recovery was also followed up.

Results

After 2 weeks of treatment, compared to conventional rehabilitation, participants who underwent rTMS treatment plus conventional rehabilitation exhibited notable enhancements in TUG, FAC, POMA, and some gait parameters [single-task gait velocity, gait stride length, gait cadence, gait cycle]. Changes in cognitive function partially mediated the improvement in single-task gait velocity and gait stride length by rTMS plus conventional rehabilitation. Generalized Estimating Equation (GEE) analysis showed that the trend of improvement in single-task gait velocity over time was more pronounced in the experimental group than in the control group. The results of the Kaplan-Meier curve indicated a median gait recovery time of 90 days for patients in the experimental group and 100 days for the control group. Multifactorial Cox regression analyses showed that rTMS plus conventional rehabilitation promoted faster recovery of independent walking compared with conventional rehabilitation.

Conclusion

rTMS plus conventional rehabilitation outperformed conventional rehabilitation in improving postural control in patients with acute ischemic stroke. Improvements in cognitive function may serve as a mediating factor in the favorable treatment outcome of rTMS plus conventional rehabilitation for improving postural control.

Clinical trial registration

https://www.chictr.org.cn, identifier ChiCTR1900026225.

Neuroimaging biomarkers for predicting stroke outcomes: A systematic review

Background and Aims

Stroke is a prominent cause of long-term adult impairment globally and a significant global health issue. Only 14% of stroke survivors achieve full recovery, while 25% to 50% require varying degrees of support, and over half become dependent. The aftermath of a stroke brings profound changes to an individual's life, with early choices significantly impacting their quality of life. This review aims to establish the efficacy of neuroimaging data in predicting long-term outcomes and recovery rates following a stroke.

Methods

A scientific literature search was conducted using the Centre of Reviews and Dissemination (CRD) criteria and PRISMA guidelines for a combined meta-narrative and systematic quantitative review. The methodology involved a structured search in databases like PubMed and The Cochrane Library, following inclusion and exclusion criteria to identify relevant studies on neuroimaging biomarkers for stroke outcome prediction. Data collection utilized the Microsoft Edge Zotero plugin, with quality appraisal conducted via the CASP checklist. Studies published from 2010 to 2024, including observational, randomized control trials, case reports, and clinical trials. Non-English and incomplete studies were excluded, resulting in the identification of 11 pertinent articles. Data extraction emphasized study methodologies, stroke conditions, clinical parameters, and biomarkers, aiming to provide a thorough literature overview and evaluate the significance of neuroimaging biomarkers in predicting stroke recovery outcomes.

Results

The results of this systematic review indicate that integrating advanced neuroimaging methods with highly successful reperfusion therapies following a stroke facilitates the diagnosis of the condition and assists in improving neurological impairments resulting from stroke. These measures reduce the possibility of death and improve the treatment provided to stroke patients.

Conclusion

These findings highlight the crucial role of neuroimaging in advancing our understanding of post-stroke outcomes and improving patient care.

Transcranial Direct Current Stimulation to Ameliorate Post-Stroke Cognitive Impairment

Post-stroke cognitive impairment is a common and disabling condition with few effective therapeutic options. After stroke, neural reorganization and other neuroplastic processes occur in response to ischemic injury, which can result in clinical improvement through spontaneous recovery. Neuromodulation through transcranial direct current stimulation (tDCS) is a promising intervention to augment underlying neuroplasticity in order to improve cognitive function. This form of neuromodulation leverages mechanisms of neuroplasticity post-stroke to optimize neural reorganization and improve function. In this review, we summarize the current state of cognitive neurorehabilitation post-stroke, the practical features of tDCS, its uses in stroke-related cognitive impairment across cognitive domains, and special considerations for the use of tDCS in the post-stroke patient population.

Neuron type-specific optogenetic stimulation for differential stroke recovery in chronic capsular infarct

Cortical neuromodulation (CNM) is widely used to promote recovery after stroke. Despite the beneficial results of CNM, the roles played by different neuron types in the effects of current CNM techniques are unable to be differentiated. Our aim was to use selective optogenetic cortical stimulation to explore how different subpopulations of neuronal cells contribute to poststroke recovery. We transduced the sensory-parietal cortex (SPC) of rats with CamKII-ChR2 (pyramidal neurons), PV-ChR2 (parvalbumin-expressing inhibitory neurons), or hSyn-ChR2 (pan-neuronal population) before inducing photothrombotic capsular infarct lesions. We found that selective stimulation of inhibitory neurons resulted in significantly greater motor recovery than stimulation of excitatory neurons or the pan-neuronal population. Furthermore, 2-deoxy-2-[18F] fluoro-D-glucose microPET (FDG-microPET) imaging revealed a significant reduction in cortical diaschisis and activation of the corticostriatal neural circuit, which were correlated with behavioral recovery in the PV-ChR2 group. The spatial pattern of brain-derived neurotrophic factor (BDNF) expression was evident in the stimulated cortex and underlying cortico-subcortical circuit. Our results indicate that the plasticity of inhibitory neurons is crucial for functional recovery after capsular infarct. Modifying CNM parameters to potentiate the stimulation of inhibitory neurons could improve poststroke outcomes.

Myoelectric control and virtual reality to enhance motor rehabilitation after stroke

Effective upper-limb rehabilitation for severely impaired stroke survivors is still missing. Recent studies endorse novel motor rehabilitation approaches such as robotic exoskeletons and virtual reality systems to restore the function of the paretic limb of stroke survivors. However, the optimal way to promote the functional reorganization of the central nervous system after a stroke has yet to be uncovered. Electromyographic (EMG) signals have been employed for prosthetic control, but their application to rehabilitation has been limited. Here we propose a novel approach to promote the reorganization of pathological muscle activation patterns and enhance upper-limb motor recovery in stroke survivors by using an EMG-controlled interface to provide personalized assistance while performing movements in virtual reality (VR). We suggest that altering the visual feedback to improve motor performance in VR, thereby reducing the effect of deviations of the actual, dysfunctional muscle patterns from the functional ones, will actively engage patients in motor learning and facilitate the restoration of functional muscle patterns. An EMG-controlled VR interface may facilitate effective rehabilitation by targeting specific changes in the structure of muscle synergies and in their activations that emerged after a stroke-offering the possibility to provide rehabilitation therapies addressing specific individual impairments.

Analysis of Motor Learning Principles Applied in Tasks or Motor Skills Trained by Stroke Patients

Objective:

To analyze the principles applied to promote and evaluate motor learning in tasks or motor skills trained by stroke patients.

Methods:

Articles were included if they used motor learning principles in tasks or motor skills trained by stroke patients.

Results:

Twelve studies were included in this review. Quality was good for the included studies. Articles used motor learning principle based on practice (N = 12), repetitive training (N = 9), and feedback (N = 5).

Conclusions:

There are different motor learning principles to promote and evaluate motor learning in stroke patients. These findings could guide clinicians during training of tasks or motor skills.

Corticospinal-specific Shh overexpression in combination with rehabilitation promotes CST axonal sprouting and skilled motor functional recovery after ischemic stroke

Ischemic stroke often leads to permanent neurological impairments, largely due to limited neuroplasticity in adult central nervous system. Here, we first showed that the expression of Sonic Hedgehog (Shh) in corticospinal neurons (CSNs) peaked at the 2nd postnatal week, when corticospinal synaptogenesis occurs. Overexpression of Shh in adult CSNs did not affect motor functions and had borderline effects on promoting the recovery of skilled locomotion following ischemic stroke. In contrast, CSNs-specific Shh overexpression significantly enhanced the efficacy of rehabilitative training, resulting in robust axonal sprouting and synaptogenesis of corticospinal axons into the denervated spinal cord, along with significantly improved behavioral outcomes. Mechanistically, combinatory treatment led to additional mTOR activation in CSNs when compared to that evoked by rehabilitative training alone. Taken together, our study unveiled a role of Shh, a morphogen involved in early development, in enhancing neuroplasticity, which significantly improved the outcomes of rehabilitative training. These results thus provide novel insights into the design of combinatory treatment for stroke and traumatic central nervous system injuries.

Alternate Day Fasting Leads to Improved Post-Stroke Motor Recovery in Mice

BACKGROUND

Caloric restriction promotes neuroplasticity and recovery after neurological injury. In mice, we tested the hypothesis that caloric restriction can act post-stroke to enhance training-associated motor recovery.

METHODS

Mice were trained to perform a skilled prehension task. We then induced a photothrombotic stroke in the caudal forelimb area, after which we retrained animals on the prehension task following an 8-day delay. Mice underwent either ad libitum feeding or alternate day fasting beginning 1-day after stroke and persisting for either 7 days or the entire post-stroke training period until sacrifice.

RESULTS

Prior studies have shown that post-stroke recovery of prehension can occur if animals receive rehabilitative training during an early sensitive period but is incomplete if rehabilitative training is delayed. In contrast, we show complete recovery of prehension, despite a delay in rehabilitative training, when mice underwent alternate day fasting beginning 1-day post-stroke and persisting for either 7 days or the entire post-stroke training period until sacrifice. Recovery was independent of weight loss. Stroke volumes were similar across groups.

CONCLUSIONS

Post-stroke caloric restriction led to recovery of motor function independent of a protective effect on stroke volume. Prehension recovery improved even after ad libitum feeding was reinstituted suggesting that the observed motor recovery was not merely a motivational response. These data add to the growing evidence that post-stroke caloric restriction can enhance recovery.

Sleep and motor learning in stroke (SMiLES): a longitudinal study investigating sleep-dependent consolidation of motor sequence learning in the context of recovery after stroke

INTRODUCTION

There is growing evidence that sleep is disrupted after stroke, with worse sleep relating to poorer motor outcomes. It is also widely acknowledged that consolidation of motor learning, a critical component of poststroke recovery, is sleep-dependent. However, whether the relationship between disrupted sleep and poor outcomes after stroke is related to direct interference of sleep-dependent motor consolidation processes, is currently unknown. Therefore, the aim of the present study is to understand whether measures of motor consolidation mediate the relationship between sleep and clinical motor outcomes post stroke.

METHODS AND ANALYSIS

We will conduct a longitudinal observational study of up to 150 participants diagnosed with stroke affecting the upper limb. Participants will be recruited and assessed within 7 days of their stroke and followed up at approximately 1 and 6 months. The primary objective of the study is to determine whether sleep in the subacute phase of recovery explains the variability in upper limb motor outcomes after stroke (over and above predicted recovery potential from the Predict Recovery Potential algorithm) and whether this relationship is dependent on consolidation of motor learning. We will also test whether motor consolidation mediates the relationship between sleep and whole-body clinical motor outcomes, whether motor consolidation is associated with specific electrophysiological sleep signals and sleep alterations during subacute recovery.

ETHICS AND DISSEMINATION

This trial has received both Health Research Authority, Health and Care Research Wales and National Research Ethics Service approval (IRAS: 304135; REC: 22/LO/0353). The results of this trial will help to enhance our understanding of the role of sleep in recovery of motor function after stroke and will be disseminated via presentations at scientific conferences, peer-reviewed publication, public engagement events, stakeholder organisations and other forms of media where appropriate.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov: NCT05746260, registered on 27 February 2023.

Benefits of Robot-Assisted Upper-Limb Rehabilitation from the Subacute Stage after a Stroke of Varying Severity: A Multicenter Randomized Controlled Trial

BACKGROUND

The aim of this study was to compare the clinical effectiveness of robot-assisted therapy with that of conventional occupational therapy according to the onset and severity of stroke.

METHODS

In this multicenter randomized controlled trial, stroke patients were randomized (1:1) to receive robot-assisted therapy or conventional occupational therapy. The robot-assisted training group received 30 min of robot-assisted therapy twice and 30 min of conventional occupational therapy daily, while the conventional therapy group received 90 min of occupational therapy. Therapy was conducted 5 days/week for 4 weeks. The primary outcome was the Wolf Motor Function Test (WMFT) score after 4 and 8 weeks of therapy.

RESULTS

Overall, 113 and 115 patients received robot-assisted and conventional therapy, respectively. The WMFT score after robot-assisted therapy was not significantly better than that after conventional therapy, but there were significant improvements in the Motricity Index (trunk) and the Fugl-Meyer Assessment. After robot-assisted therapy, wrist strength significantly improved in the subacute or moderate-severity group of stroke patients.

CONCLUSIONS

Robot-assisted therapy improved the upper-limb functions and activities of daily living (ADL) performance as much as conventional occupational therapy. In particular, it showed signs of more therapeutic effectiveness in the subacute stage or moderate-severity group.

Brain computer interface training with motor imagery and functional electrical stimulation for patients with severe upper limb paresis after stroke: a randomized controlled pilot trial

BACKGROUND

Restorative Brain-Computer Interfaces (BCI) that combine motor imagery with visual feedback and functional electrical stimulation (FES) may offer much-needed treatment alternatives for patients with severely impaired upper limb (UL) function after a stroke.

OBJECTIVES

This study aimed to examine if BCI-based training, combining motor imagery with FES targeting finger/wrist extensors, is more effective in improving severely impaired UL motor function than conventional therapy in the subacute phase after stroke, and if patients with preserved cortical-spinal tract (CST) integrity benefit more from BCI training.

METHODS

Forty patients with severe UL paresis (< 13 on Action Research Arm Test (ARAT) were randomized to either a 12-session BCI training as part of their rehabilitation or conventional UL rehabilitation. BCI sessions were conducted 3-4 times weekly for 3-4 weeks. At baseline, Transcranial Magnetic Stimulation (TMS) was performed to examine CST integrity. The main endpoint was the ARAT at 3 months post-stroke. A binominal logistic regression was conducted to examine the effect of treatment group and CST integrity on achieving meaningful improvement. In the BCI group, electroencephalographic (EEG) data were analyzed to investigate changes in event-related desynchronization (ERD) during the course of therapy.

RESULTS

Data from 35 patients (15 in the BCI group and 20 in the control group) were analyzed at 3-month follow-up. Few patients (10/35) improved above the minimally clinically important difference of 6 points on ARAT, 5/15 in the BCI group, 5/20 in control. An independent-samples Mann-Whitney U test revealed no differences between the two groups, p = 0.382. In the logistic regression only CST integrity was a significant predictor for improving UL motor function, p = 0.007. The EEG analysis showed significant changes in ERD of the affected hemisphere and its lateralization only during unaffected UL motor imagery at the end of the therapy.

CONCLUSION

This is the first RCT examining BCI training in the subacute phase where only patients with severe UL paresis were included. Though more patients in the BCI group improved relative to the group size, the difference between the groups was not significant. In the present study, preserved CTS integrity was much more vital for UL improvement than which type of intervention the patients received. Larger studies including only patients with some preserved CST integrity should be attempted.

Error Enhancement for Upper Limb Rehabilitation in the Chronic Phase after Stroke: A 5-Day Pre-Post Intervention Study

A large proportion of chronic stroke survivors still struggle with upper limb (UL) problems in daily activities, typically reaching tasks. During three-dimensional reaching movements, the deXtreme robot offers error enhancement forces. Error enhancement aims to improve the quality of movement. We investigated clinical and patient-reported outcomes and assessed the quality of movement before and after a 5 h error enhancement training with the deXtreme robot. This pilot study had a pre-post intervention design, recruiting 22 patients (mean age: 57 years, mean days post-stroke: 1571, male/female: 12/10) in the chronic phase post-stroke with UL motor impairments. Patients received 1 h robot treatment for five days and were assessed at baseline and after training, collecting (1) clinical, (2) patient-reported, and (3) kinematic (KINARM, BKIN Technologies Ltd., Kingston, ON, Canada) outcome measures. Our analysis revealed significant improvements (median improvement (Q1-Q3)) in (1) UL Fugl-Meyer assessment (1.0 (0.8-3.0), p < 0.001) and action research arm test (2.0 (0.8-2.0), p < 0.001); (2) motor activity log, amount of use (0.1 (0.0-0.3), p < 0.001) and quality of use (0.1 (0.1-0.5), p < 0.001) subscale; (3) KINARM-evaluated position sense (-0.45 (-0.81-0.09), p = 0.030) after training. These findings provide insight into clinical self-reported and kinematic improvements in UL functioning after five hours of error enhancement UL training.

Cycling using functional electrical stimulation therapy to improve motor function and activity in post-stroke individuals in early subacute phase: a systematic review with meta-analysis

BACKGROUND

Stroke necessitates interventions to rehabilitate individuals with disabilities, and the application of functional electrical stimulation therapy (FEST) has demonstrated potential in this regard. This study aimed to analyze the efficacy and effectiveness of cycling using FEST to improve motor function and lower limb activity in post-stroke individuals.

METHODS

We performed a systematic review according to the recommendations of the PRISMA checklist, searching MEDLINE, Cochrane, EMBASE, LILACS, and PEDro databases by July 2022, without any date or language limitations. Studies were selected using the following terms: stroke, electrical stimulation therapy, cycling, and clinical trials. Randomized or quasi-randomized clinical trials that investigated the effectiveness of cycling using FEST combined with exercise programs and cycling using FEST alone for motor function and activity in subacute post-stroke individuals were included. The quality of included trials was assessed using the PEDro scores. Outcome data were extracted from eligible studies and combined in random-effects meta-analyses. The quality of evidence was determined according to the Grading of Recommendations Assessment, Development, and Evaluation system.

RESULTS

Five randomized clinical trials involving 187 participants were included. Moderate-quality evidence indicates that cycling using FEST combined with exercise programs promotes relevant benefits in trunk control (MD 9 points, 95% CI 0.36-17.64) and walking distance (MD 94.84 m, 95% CI 39.63-150.05, I = 0%), the other outcomes had similar benefits. Cycling using FEST alone compared to exercise programs promotes similar benefits in strength, balance, walking speed, walking distance, and activities of daily living.

CONCLUSION

This systematic review provides low- to moderate-quality evidence that cycling using FEST may be an effective strategy to consider in improving motor function and activity outcomes for post-stroke individuals in the early subacute phase.

REVIEW REGISTRATION

PROSPERO (CRD42022345282).

Astrocyte Regulation of Neuronal Function and Survival in Stroke Pathophysiology

The interactions between astrocytes and neurons in the context of stroke play crucial roles in the disease's progression and eventual outcomes. After a stroke, astrocytes undergo significant changes in their morphology, molecular profile, and function, together termed reactive astrogliosis. Many of these changes modulate how astrocytes relate to neurons, inducing mechanisms both beneficial and detrimental to stroke recovery. For example, excessive glutamate release and astrocytic malfunction contribute to excitotoxicity in stroke, eventually causing neuronal death. Astrocytes also provide essential metabolic support and neurotrophic signals to neurons after stroke, ensuring homeostatic stability and promoting neuronal survival. Furthermore, several astrocyte-secreted molecules regulate synaptic plasticity in response to stroke, allowing for the rewiring of neural circuits to compensate for damaged areas. In this chapter, we highlight the current understanding of the interactions between astrocytes and neurons in response to stroke, explaining the varied mechanisms contributing to injury progression and the potential implications for future therapeutic interventions.

Noninvasive cerebellar stimulation and behavioral interventions: A crucial synergy for post-stroke motor rehabilitation

BACKGROUND

Improvement of functional movements after supratentorial stroke occurs through spontaneous biological recovery and training-induced reorganization of remnant neural networks. The cerebellum, through its connectivity with the cortex, brainstem and spinal cord, is actively engaged in both recovery and reorganization processes within the cognitive and sensorimotor systems. Noninvasive cerebellar stimulation (NiCBS) offers a safe, clinically feasible and potentially effective way to modulate the excitability of spared neural networks and promote movement recovery after supratentorial stroke. NiCBS modulates cerebellar connectivity to the cerebral cortex and brainstem, as well as influences the sensorimotor and frontoparietal networks.

OBJECTIVE

Our objective was twofold: (a) to conduct a scoping review of studies that employed NiCBS to influence motor recovery and learning in individuals with stroke, and (b) to present a theory-driven framework to inform the use of NiCBS to target distinct stroke-related deficits.

METHODS

A scoping review of current research up to August 2023 was conducted to determine the effect size of NiCBS effect on movement recovery of upper extremity function, balance, walking and motor learning in humans with stroke.

RESULTS

Calculated effect sizes were moderate to high, offering promise for improving upper extremity, balance and walking outcomes after stroke. We present a conceptual framework that capitalizes on cognitive-motor specialization of the cerebellum to formulate a synergy between NiCBS and behavioral interventions to target specific movement deficits.

CONCLUSION

NiCBS enhances recovery of upper extremity impairments, balance and walking after stroke. Physiologically-informed synergies between NiCBS and behavioral interventions have the potential to enhance recovery. Finally, we propose future directions in neurophysiological, behavioral, and clinical research to move NiCBS through the translational pipeline and augment motor recovery after stroke.

Trunk postural reactions to the force perturbation intensity and frequency during sitting astride in children with cerebral palsy

The purpose of this study was to examine kinematic and neuromuscular responses of the head and body to pelvis perturbations with different intensities and frequencies during sitting astride in children with CP. Sixteen children with spastic CP (mean age 7.4 ± 2.4 years old) were recruited in this study. A custom designed cable-driven robotic horse was used to apply controlled force perturbations to the pelvis during sitting astride. Each participant was tested in four force intensity conditions (i.e., 10%, 15%, 20%, and 25% of body weight (BW), frequency = 1 Hz), and six force frequency conditions (i.e., 0.5 Hz, 1 Hz, 1.5 Hz, 2 Hz, 2.5 Hz, and 3 Hz, intensity = 20% of BW). Each testing session lasted for one minute with a one-minute rest break inserted between two sessions. Kinematic data of the head, trunk, and legs were recorded using wearable sensors, and EMG signals of neck, trunk, and leg muscles were recorded. Children with CP showed direction-specific trunk and neck muscle activity in response to the pelvis perturbations during sitting astride. Greater EMG activities of trunk and neck muscles were observed for the greater intensities of force perturbations (P < .05). Participants also showed enhanced activation of antagonistic muscles rather than direction-specific trunk and neck muscle activities for the conditions of higher frequency perturbations (P < .05). Children with CP may modulate trunk and neck muscle activities in response to greater changes in intensity of pelvis perturbation during sitting astride. Perturbations with too high frequency may be less effective in inducing direction-specific trunk and neck muscle activities.

The support dilemma of stroke inpatients and family caregivers under COVID-19 prevention and control: a qualitative study in China

China has implemented a strict isolation system in hospitals since the COVID-19 pandemic, that adversely affected the psychology of inpatients and their caregivers. Face-to-face, semi-structured interviews with 22 stroke inpatients from two municipal hospitals were conducted to explore the psychological, emotional and related support needs of stroke inpatients and their family caregivers under this environment. Results which showed that external support for stroke inpatients and their family caregivers was insufficient highlight the necessity for developing specific nursing interventions that meet the psychological and emotional needs of inpatients and the caregivers.

Reliability of a TMS-derived threshold matrix of corticomotor function

Transcranial magnetic stimulation (TMS) studies typically focus on suprathreshold motor evoked potentials (MEPs), overlooking small MEPs representing subthreshold corticomotor pathway activation. Assessing subthreshold excitability could provide insights into corticomotor pathway integrity and function, particularly in neurological conditions like stroke. The aim of the study was to examine the test-retest reliability of metrics derived from a novel compositional analysis of MEP data from older adults. The study also compared the composition between the dominant (D) and non-dominant (ND) sides and explored the association between subthreshold responses and resting motor threshold. In this proof-of-concept study, 23 healthy older adults participated in two identical experimental sessions. Stimulus-response (S-R) curves and threshold matrices were constructed using single-pulse TMS across intensities to obtain MEPs in four upper limb muscles. S-R curves had reliable slopes for every muscle (Intraclass Correlation Coefficient range = 0.58-0.88). Subliminal and suprathreshold elements of the threshold matrix showed good-excellent reliability (D subliminal ICC = 0.83; ND subliminal ICC = 0.79; D suprathreshold ICC = 0.92; ND suprathreshold ICC = 0.94). By contrast, subthreshold elements of the matrix showed poor reliability, presumably due to a floor effect (D subthreshold ICC = 0.39; ND subthreshold ICC = 0.05). No composition differences were found between D and ND sides (suprathreshold BF01 = 3.85; subthreshold BF01 = 1.68; subliminal BF01 = 3.49). The threshold matrix reliably assesses subliminal and suprathreshold MEPs in older adults. Further studies are warranted to evaluate the utility of compositional analyses for assessing recovery of corticomotor pathway function after neurological injury.

Against cortical reorganisation

Neurological insults, such as congenital blindness, deafness, amputation, and stroke, often result in surprising and impressive behavioural changes. Cortical reorganisation, which refers to preserved brain tissue taking on a new functional role, is often invoked to account for these behavioural changes. Here, we revisit many of the classical animal and patient cortical remapping studies that spawned this notion of reorganisation. We highlight empirical, methodological, and conceptual problems that call this notion into doubt. We argue that appeal to the idea of reorganisation is attributable in part to the way that cortical maps are empirically derived. Specifically, cortical maps are often defined based on oversimplified assumptions of 'winner-takes-all', which in turn leads to an erroneous interpretation of what it means when these maps appear to change. Conceptually, remapping is interpreted as a circuit receiving novel input and processing it in a way unrelated to its original function. This implies that neurons are either pluripotent enough to change what they are tuned to or that a circuit can change what it computes. Instead of reorganisation, we argue that remapping is more likely to occur due to potentiation of pre-existing architecture that already has the requisite representational and computational capacity pre-injury. This architecture can be facilitated via Hebbian and homeostatic plasticity mechanisms. Crucially, our revised framework proposes that opportunities for functional change are constrained throughout the lifespan by the underlying structural 'blueprint'. At no period, including early in development, does the cortex offer structural opportunities for functional pluripotency. We conclude that reorganisation as a distinct form of cortical plasticity, ubiquitously evoked with words such as 'take-over'' and 'rewiring', does not exist.

Cross-modal exposure restores multisensory enhancement after hemianopia

Hemianopia is a common consequence of unilateral damage to visual cortex that manifests as a profound blindness in contralesional space. A noninvasive cross-modal (visual-auditory) exposure paradigm has been developed in an animal model to ameliorate this disorder. Repeated stimulation of a visual-auditory stimulus restores overt responses to visual stimuli in the blinded hemifield. It is believed to accomplish this by enhancing the visual sensitivity of circuits remaining after a lesion of visual cortex; in particular, circuits involving the multisensory neurons of the superior colliculus. Neurons in this midbrain structure are known to integrate spatiotemporally congruent visual and auditory signals to amplify their responses, which, in turn, enhances behavioral performance. Here we evaluated the relationship between the rehabilitation of hemianopia and this process of multisensory integration. Induction of hemianopia also eliminated multisensory enhancement in the blinded hemifield. Both vision and multisensory enhancement rapidly recovered with the rehabilitative cross-modal exposures. However, although both reached pre-lesion levels at similar rates, they did so with different spatial patterns. The results suggest that the capability for multisensory integration and enhancement is not a pre-requisite for visual recovery in hemianopia, and that the underlying mechanisms for recovery may be more complex than currently appreciated.

Mapping physical activity patterns in hospitalised patients with moderate to severe acquired brain injury - MAP-ABI: Protocol for an observational study

Introduction

The physical activity level in patients hospitalised for rehabilitation across multiple diagnoses is low. Moderate to severe acquired brain injury further reduces activity levels as impaired physical and cognitive functioning affect mobility independence. Therefore, supervised out-of-bed mobilisation and physical activity training are essential rehabilitation strategies. Few studies have measured the physical activity patterns in the early phases of rehabilitation after moderate to severe brain injury.

Objectives

To map and quantify physical activity patterns in patients admitted to brain injury rehabilitation. Further, to investigate which factors are associated with activity and if the early physical activity level is associated with functional outcome at discharge.

Methods

This observational study includes patients admitted to rehabilitation after moderate to severe acquired brain injury. Mobility and physical activity patterns are measured continuously during rehabilitation at two separate seven-day periods using a wearable activity tracker. Activity will be categorised into four levels and presented descriptively. Linear and logistic regression models will analyse associations between descriptive variables and activity levels.

Discussion

This protocol describes an observational study investigating patients' mobility and physical activity patterns with moderate to severe acquired brain injury during in-hospital rehabilitation. The ability to increase the amount of mobilisation and physical activity in subgroups may have profound consequences on the rehabilitation outcome. Furthermore, data from this study may be used to inform a large variety of trials investigating physical rehabilitation interventions. (NCT05571462).

Feasibility and outcomes of supplemental gait training by robotic and conventional means in acute stroke rehabilitation

INTRODUCTION

Practicality of implementation and dosing of supplemental gait training in an acute stroke inpatient rehabilitation setting are not well studied but can have positive impact on outcomes.

OBJECTIVES

To determine the feasibility of early, intense supplemental gait training in inpatient stroke rehabilitation, compare functional outcomes and the specific mode of delivery.

DESIGN AND SETTING

Assessor blinded, randomized controlled trial in a tertiary Inpatient Rehabilitation Facility.

PARTICIPANTS

Thirty acute post-stroke patients with unilateral hemiparesis (≥ 18 years of age with a lower limb MAS ≤ 3).

INTERVENTION

Lokomat® or conventional gait training (CGT) in addition to standard mandated therapy time.

MAIN OUTCOME MEASURES

Number of therapy sessions; adverse events; functional independence measure (FIM motor); functional ambulation category (FAC); passive range of motion (PROM); modified Ashworth scale (MAS); 5 times sit-to-stand (5x-STS); 10-m walk test (10MWT); 2-min walk test (2MWT) were assessed before (pre) and after training (post).

RESULTS

The desired supplemental therapy was implemented during normal care delivery hours and the patients generally tolerated the sessions well. Both groups improved markedly on several measures; the CGT group obtained nearly 45% more supplemental sessions (12.8) than the Lokomat® group (8.9). Both groups showed greater FIM improvement scores (discharge - admission) than those from a reference group receiving no supplemental therapy. An overarching statistical comparison between methods was skewed towards a differential benefit (but not significant) in the Lokomat® group with medium effect sizes. By observation, the robotic group completed a greater number of steps, on average. These results provide some evidence for Lokomat® being a more efficient tool for gait retraining by providing a more optimal therapy "dose".

CONCLUSIONS

With careful planning, supplemental therapy was possible with minimal intrusion to schedules and was well tolerated. Participants showed meaningful functional improvement with relatively little supplemental therapy over a relatively short time in study.

Adaptive Neuroplasticity in Brain Injury Recovery: Strategies and Insights

This review addresses the relationship between neuroplasticity and recovery from brain damage. Neuroplasticity's ability to adapt becomes crucial since brain injuries frequently result in severe impairments. We begin by describing the fundamentals of neuroplasticity and how it relates to rehabilitation. Examining different forms of brain injuries and their neurological effects highlights the complex difficulties in rehabilitation. By revealing cellular processes, we shed light on synaptic adaptability following damage. Our study of synaptic plasticity digs into axonal sprouting, dendritic remodeling, and the balance of long-term potentiation. These processes depict neural resilience amid change. Then, after damage, we investigate immediate and slow neuroplastic alterations, separating reorganizations that are adaptive from those that are maladaptive. As we go on to rehabilitation, we evaluate techniques that use neuroplasticity's potential. These methods take advantage of the brain's plasticity for healing, from virtual reality and brain-computer interfaces to constraint-induced movement therapy. Ethics and individualized neurorehabilitation are explored. We scrutinize the promise of combination therapy and the difficulties in putting new knowledge into clinical practice. In conclusion, this analysis highlights neuroplasticity's critical role in brain injury recovery, providing sophisticated approaches to improve life after damage.

Modulation of neurotrophic factors in the treatment of dementia, stroke and TBI: Effects of Cerebrolysin

Neurotrophic factors (NTFs) are involved in the pathophysiology of neurological disorders such as dementia, stroke and traumatic brain injury (TBI), and constitute molecular targets of high interest for the therapy of these pathologies. In this review we provide an overview of current knowledge of the definition, discovery and mode of action of five NTFs, nerve growth factor, insulin-like growth factor 1, brain derived NTF, vascular endothelial growth factor and tumor necrosis factor alpha; as well as on their contribution to brain pathology and potential therapeutic use in dementia, stroke and TBI. Within the concept of NTFs in the treatment of these pathologies, we also review the neuropeptide preparation Cerebrolysin, which has been shown to resemble the activities of NTFs and to modulate the expression level of endogenous NTFs. Cerebrolysin has demonstrated beneficial treatment capabilities in vitro and in clinical studies, which are discussed within the context of the biochemistry of NTFs. The review focuses on the interactions of different NTFs, rather than addressing a single NTF, by outlining their signaling network and by reviewing their effect on clinical outcome in prevalent brain pathologies. The effects of the interactions of these NTFs and Cerebrolysin on neuroplasticity, neurogenesis, angiogenesis and inflammation, and their relevance for the treatment of dementia, stroke and TBI are summarized.

The Effects of Stroke and Stroke Gait Rehabilitation on Behavioral and Neurophysiological Outcomes:: Challenges and Opportunities for Future Research

Stroke continues to be a leading cause of adult disability, contributing to immense healthcare costs. Even after discharge from rehabilitation, post-stroke individuals continue to have persistent gait impairments, which in turn adversely affect functional mobility and quality of life. Multiple factors, including biomechanics, energy cost, psychosocial variables, as well as the physiological function of corticospinal neural pathways influence stroke gait function and training-induced gait improvements. As a step toward addressing this challenge, the objective of the current perspective paper is to outline knowledge gaps pertinent to the measurement and retraining of stroke gait dysfunction. The paper also has recommendations for future research directions to address important knowledge gaps, especially related to the measurement and rehabilitation-induced modulation of biomechanical and neural processes underlying stroke gait dysfunction. We posit that there is a need for leveraging emerging technologies to develop innovative, comprehensive, methods to measure gait patterns quantitatively, to provide clinicians with objective measure of gait quality that can supplement conventional clinical outcomes of walking function. Additionally, we posit that there is a need for more research on how the stroke lesion affects multiple parts of the nervous system, and to understand the neuroplasticity correlates of gait training and gait recovery. Multi-modal clinical research studies that can combine clinical, biomechanical, neural, and computational modeling data provide promise for gaining new information about stroke gait dysfunction as well as the multitude of factors affecting recovery and treatment response in people with post-stroke hemiparesis.

Improved upper extremity function following low-frequency hybrid assistive neuromuscular dynamic stimulation therapy in a patient with hemiplegia: A case report

BACKGROUND

Although hybrid assistive neuromuscular dynamic stimulation (HANDS) therapy may improve upper extremity functionality in patients with paralysis or paresis due to stroke, it is usually only provided in hospitals as a frequent intervention during the phase of early recovery in stroke. Home-based rehabilitation is limited by frequency and duration of visits.

PURPOSE

To investigate the effectiveness of low-frequency HANDS therapy using motor function assessment.

STUDY DESIGN

Case report.

METHODS

We performed HANDS therapy for 1 month on the patient, who was a woman in her 70s with left-sided hemiplegia. It was initiated on day 183 post the onset of stroke. Movement and motor function were evaluated using the Fugl-Meyer Assessment upper-extremity (FMA-UE) motor items and the Motor Activity Log consisting of Amount of Use (MAL-AOU), as well as Quality of Movement (MAL-QOM) scales. This evaluation was performed before starting HANDS therapy and after its conclusion.

RESULTS

Following HANDS therapy, there was improvement in the FMA-UE (21 points → 28 points), MAL-AOU (0.17 points → 0.33 points), and MAL-QOM (0.08 points → 0.33 points) scores when compared to the scores before therapy, and the patient was able to use both hands for activities of daily living (ADLs).

CONCLUSIONS

Low-frequency HANDS therapy combined with encouragement to include the affected hand in ADLs may improve upper extremity function in cases of paralysis.

Effects of EMG-based robot for upper extremity rehabilitation on post-stroke patients: a systematic review and meta-analysis

Objective: A growing body of research shows the promise and efficacy of EMG-based robot interventions in improving the motor function in stroke survivors. However, it is still controversial whether the effect of EMG-based robot is more effective than conventional therapies. This study focused on the effects of EMG-based robot on upper limb motor control, spasticity and activity limitation in stroke survivors compared with conventional rehabilitation techniques. Methods: We searched electronic databases for relevant randomized controlled trials. Outcomes included Fugl-Meyer assessment scale (FMA), Modified Ashworth Scale (MAS), and activity level. Result: Thirteen studies with 330 subjects were included. The results showed that the outcomes post intervention was significantly improved in the EMG-based robot group. Results from subgroup analyses further revealed that the efficacy of the treatment was better in patients in the subacute stage, those who received a total treatment time of less than 1000 min, and those who received EMG-based robotic therapy combined with electrical stimulation (ES). Conclusion: The effect of EMG-based robot is superior to conventional therapies in terms of improving upper extremity motor control, spasticity and activity limitation. Further research should explore optimal parameters of EMG-based robot therapy and its long-term effects on upper limb function in post-stroke patients. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/; Identifier: 387070.

Suppression of Microglial ERO1a Alleviates Inflammation and Enhances the Efficacy of Rehabilitative Training After Ischemic Stroke

Microglia mediated inflammation plays a crucial role in cellular events and functional recovery post ischemic stroke. In the current study, we profiled the proteome changes of microglia treated with oxygen and glucose deprivation (OGD). Bioinformatics analysis identified that differentially expressed proteins (DEPs) were enriched in pathways associated with oxidate phosphorylation and mitochondrial respiratory chain at both 6h and 24h post OGD. We next focused on one validated target named endoplasmic reticulum oxidoreductase 1 alpha (ERO1a) to study its role in stroke pathophysiology. We showed that over-expression of microglial ERO1a exacerbated inflammation, cell apoptosis and behavioral outcomes post middle cerebral artery occlusion (MCAO). In contrast, suppression of microglial ERO1a significantly reduced activation of both microglia and astrocyte, along with cell apoptosis. Furthermore, knocking down microglial ERO1a improved the efficacy of rehabilitative training and enhanced the mTOR activity in spared corticospinal neurons. Our study provided novel insights into the identification of therapeutic targets and the design of rehabilitative protocols to treat ischemic stroke and other traumatic CNS injuries.

Ketone bodies promote stroke recovery via GAT-1-dependent cortical network remodeling

Stroke is a leading cause of adult disability worldwide, and better drugs are needed to promote functional recovery after stroke. Growing evidence suggests the critical role of network excitability during the repair phase for stroke recovery. Here, we show that β-hydroxybutyrate (β-HB), an essential ketone body (KB) component, is positively correlated with improved outcomes in patients with stroke and promotes functional recovery in rodents with stroke during the repair phase. These beneficial effects of β-HB depend on HDAC2/HDAC3-GABA transporter 1 (GAT-1) signaling-mediated enhancement of excitability and phasic GABA inhibition in the peri-infarct cortex and structural and functional plasticity in the ipsilateral cortex, the contralateral cortex, and the corticospinal tract. Together with available clinical approaches to elevate KB levels, our results offer a clinically translatable means to promote stroke recovery. Furthermore, GAT-1 can serve as a pharmacological target for developing drugs to promote functional recovery after stroke.

Transcranial Direct-Current Stimulation in Subacute Aphasia: A Randomized Controlled Trial

BACKGROUND

Transcranial direct-current stimulation (tDCS) is a promising adjunct to therapy for chronic aphasia.

METHODS

This single-center, randomized, double-blind, sham-controlled efficacy trial tested the hypothesis that anodal tDCS augments language therapy in subacute aphasia. Secondarily, we compared the effect of tDCS on discourse measures and quality of life and compared the effects on naming to previous findings in chronic stroke. Right-handed English speakers with aphasia <3 months after left hemisphere ischemic stroke were included, unless they had prior neurological or psychiatric disease or injury or were taking certain medications (34 excluded; final sample, 58). Participants were randomized 1:1, controlling for age, aphasia type, and severity, to receive 20 minutes of tDCS (1 mA) or sham-tDCS in addition to fifteen 45-minute sessions of naming treatment (plus standard care). The primary outcome variable was change in naming accuracy of untrained pictures pretreatment to 1-week posttreatment.

RESULTS

Baseline characteristics were similar between the tDCS (N=30) and sham (N=28) groups: patients were 65 years old, 53% male, and 2 months from stroke onset on average. In intent-to-treat analysis, the adjusted mean change from baseline to 1-week posttreatment in picture naming was 22.3 (95% CI, 13.5-31.2) for tDCS and 18.5 (9.6-27.4) for sham and was not significantly different. Content and efficiency of picture description improved more with tDCS than sham. Groups did not differ in quality of life improvement. No patients were withdrawn due to adverse events.

CONCLUSIONS

tDCS did not improve recovery of picture naming but did improve recovery of discourse. Discourse skills are critical to participation. Future research should examine tDCS in a larger sample with richer functional outcomes.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT02674490.

Nonpharmacological Treatments for Hospitalized Patients with Stroke: A Nuanced Approach to Prescribing Early Activity

Stroke remains a leading cause of adult disability. To date, hyperacute revascularization procedures reach 5-10% of stroke patients even in high resource health systems. There is a limited time window for brain repair after stroke, and therefore, the activities such as prescribed exercise in the earliest period will likely have long-term significant consequences. Clinicians who provide care for hospitalized stroke patients make treatment decisions specific to activity often without guidelines to direct these prescriptions. This requires a balanced understanding of the available evidence for early post-stroke exercise and physiological principles after stroke that drive the safety of prescribed exercise. Here, we provide a summary of these relevant concepts, identify gaps, and recommend an approach to prescribing safe and meaningful activity for all patients with stroke. The population of thrombectomy-eligible stroke patients can be used as the exemplar for conceptualization.

Magnetothermal-based non-invasive focused magnetic stimulation for functional recovery in chronic stroke treatment

Magnetic heat-based brain stimulation of specific lesions could promote the restoration of impaired motor function caused by chronic stroke. We delivered localized stimulation by nanoparticle-mediated heat generation within the targeted brain area via focused magnetic stimulation. The middle cerebral artery occlusion model was prepared, and functional recovery in the chronic-phase stroke rat model was demonstrated by the therapeutic application of focused magnetic stimulation. We observed a transient increase in blood-brain barrier permeability at the target site of < 4 mm and metabolic brain activation at the target lesion. After focused magnetic stimulation, the rotarod score increased by 390 ± 28% (p < 0.05) compared to the control group. Standardized uptake value in the focused magnetic stimulation group increased by 2063 ± 748% (p < 0.01) compared to the control group. Moreover, an increase by 24 ± 5% (p < 0.05) was observed in the sham group as well. Our results show that non-invasive focused magnetic stimulation can safely modulate BBB permeability and enhance neural activation for chronic-phase stroke treatment in the targeted deep brain area.