Neural Patterns of Reorganization after Intensive Robot-Assisted Virtual Reality Therapy and Repetitive Task Practice in Patients with Chronic Stroke

Effectiveness of combined robotics and virtual reality on lower limb functional ability in stroke survivors: A systematic review of randomized controlled trials

Lower limb impairments are common consequences of stroke. Robotics and virtual reality (VR) play crucial roles in improving lower limb function post-stroke. This review aims to assess the effects of combined robot and VR interventions on lower limb functional ability poststroke and to provide recommendations for future studies in the rehabilitation field. PubMed, SCOPUS, CINAHL, MEDLINE, EMBASE, and Web of Science were searched from inception to March 1, 2024. Randomized controlled trials (RCTs) involving patients with a stroke, administering combined robot and VR compared with passive (i.e., rest) or active (any intervention), and including at least one outcome evaluating lower limb function (i.e., balance, gait, mobility, muscle tone, muscle strength, range of motion) or activities of daily living were selected. The Cochrane Collaboration tool was employed to evaluate the risk of bias in the included studies. Nine studies met the eligibility criteria. In total, 364 stroke survivors (Mean age 55.62 years) were involved in this review. According to the Cochrane Collaboration tool, five studies were classified as "high quality," "moderate quality" (n=3), and "low quality" (n=1). There are mixed findings on the effects of combined robot and VR on lower limb functional ability in stroke survivors. The evidence for the effects of combined robot and VR on lower limb functional ability post-stroke is promising. Further trials with long-term follow-up are strongly warranted to understand the immediate and long-term effect of combined robot and VR intervention on various lower limb impairments and to define the optimal treatment protocols.

Combined noninvasive brain stimulation virtual reality for upper limb rehabilitation poststroke: A systematic review of randomized controlled trials

Upper limb impairments are common consequences of stroke. Noninvasive brain stimulation (NIBS) and virtual reality (VR) play crucial roles in improving upper limb function poststroke. This review aims to evaluate the effects of combined NIBS and VR interventions on upper limb function post-stroke and to provide recommendations for future studies in the rehabilitation field. PubMed, MEDLINE, PEDro, SCOPUS, REHABDATA, EMBASE, and Web of Science were searched from inception to November 2023. Randomized controlled trials (RCTs) encompassed patients with a confirmed stroke diagnosis, administrated combined NIBS and VR compared with passive (i.e., rest) or active (conventional therapy), and included at least one outcome assessing upper limb function (i.e., strength, spasticity, function) were selected. The quality of the included studies was assessed using the Cochrane Collaboration tool. Seven studies met the eligibility criteria. In total, 303 stroke survivors (Mean age: 61.74 years) were included in this review. According to the Cochrane Collaboration tool, five studies were classified as "high quality," while two were categorized as "moderate quality". There are mixed findings for the effects of combined NIBS and VR on upper limb function in stroke survivors. The evidence for the effects of combined transcranial direct current stimulation and VR on upper limb function post-stroke is promising. However, the evidence regarding the effects of combined repetitive transcranial magnetic stimulation and VR on upper limb function is limited. Further randomized controlled trials with long-term follow-up are strongly warranted.

360° immersive virtual reality-based mirror therapy for upper extremity function and satisfaction among stroke patients: a randomized controlled trial

BACKGROUND

Stroke is a leading cause of long-term disability worldwide; therefore, an effective rehabilitation strategy is fundamental. Mirror therapy (MT) has been a popular approach for upper extremity rehabilitation, but it presents some limitations. Recent advancements in virtual reality (VR) technology have introduced immersive VR-based MT, potentially overcoming these limitations and enhancing rehabilitation outcomes.

AIM

This study aimed to evaluate the effectiveness of a novel 360° immersive virtual reality-based MT (360MT) in upper extremity rehabilitation for stroke patients, comparing it to traditional MT (TMT) and conventional physical therapy control group (CG).

DESIGN

A prospective, active control, assessor blinded, parallel groups, randomized controlled trial.

POPULATION

Forty-five participants with chronic stroke within six months of onset.

METHODS

The participants were randomly allocated to 360MT, TMT, or CG groups. Outcome measures included Fugl-Meyer Assessment for Upper Extremity (FMA-UE), Box and Block Test (BBT), and Manual Function Test (MFT). Additionally, patient experience and satisfaction in the groups of 360MT and TMT were assessed through questionnaires and interviews.

RESULTS

Results revealed that the 360MT group showed significantly greater improvements in FMA-UE, MFT and BBT compared to TMT (P<0.05) and CG (P<0.001) groups. Patient experience and satisfaction were more favorable in the 360MT group, with participants reporting higher engagement and motivation.

CONCLUSIONS

360MT appears to be a promising approach for upper extremity rehabilitation in stroke patients, providing better outcomes and higher patient satisfaction. However, further research is needed to confirm these findings and strengthen the evidence base for 360MT in stroke rehabilitation.

CLINICAL REHABILITATION IMPACT

360MT demonstrated notably enhanced upper extremity rehabilitation outcomes as well as better patient satisfaction among chronic stroke patients within six months of onset compared to traditional MT and conventional physical therapy. This novel approach not only fostered functional improvements but also elevated levels of engagement and motivation among participants, suggesting a promising future application in stroke rehabilitation framework.

Graph analysis of cortical reorganization after virtual reality-based rehabilitation following stroke: a pilot randomized study

Introduction

Stroke is the leading cause of functional disability worldwide. With the increase of the global population, motor rehabilitation of stroke survivors is of ever-increasing importance. In the last decade, virtual reality (VR) technologies for rehabilitation have been extensively studied, to be used instead of or together with conventional treatments such as physiotherapy or occupational therapy. The aim of this work was to evaluate the GestureCollection VR-based rehabilitation tool in terms of the brain changes and clinical outcomes of the patients.

Methods

Two groups of chronic patients underwent a rehabilitation treatment with (experimental) or without (control) complementation with GestureCollection. Functional magnetic resonance imaging exams and clinical assessments were performed before and after the treatment. A functional connectivity graph-based analysis was used to assess differences between the connections and in the network parameters strength and clustering coefficient.

Results

Patients in both groups showed improvement in clinical scales, but there were more increases in functional connectivity in the experimental group than in the control group.

Discussion

The experimental group presented changes in the connections between the frontoparietal and the somatomotor networks, associative cerebellum and basal ganglia, which are regions associated with reward-based motor learning. On the other hand, the control group also had results in the somatomotor network, in its ipsilateral connections with the thalamus and with the motor cerebellum, which are regions more related to a purely mechanical activity. Thus, the use of the GestureCollection system was successfully shown to promote neuroplasticity in several motor-related areas.

Neural Plasticity Changes Induced by Motor Robotic Rehabilitation in Stroke Patients: The Contribution of Functional Neuroimaging

Robotic rehabilitation is one of the most advanced treatments helping people with stroke to faster recovery from motor deficits. The clinical impact of this type of treatment has been widely defined and established using clinical scales. The neurofunctional indicators of motor recovery following conventional rehabilitation treatments have already been identified by previous meta-analytic investigations. However, a clear definition of the neural correlates associated with robotic neurorehabilitation treatment has never been performed. This systematic review assesses the neurofunctional correlates (fMRI, fNIRS) of cutting-edge robotic therapies in enhancing motor recovery of stroke populations in accordance with PRISMA standards. A total of 7, of the initial yield of 150 articles, have been included in this review. Lessons from these studies suggest that neural plasticity within the ipsilateral primary motor cortex, the contralateral sensorimotor cortex, and the premotor cortices are more sensitive to compensation strategies reflecting upper and lower limbs' motor recovery despite the high heterogeneity in robotic devices, clinical status, and neuroimaging procedures. Unfortunately, the paucity of RCT studies prevents us from understanding the neurobiological differences induced by robotic devices with respect to traditional rehabilitation approaches. Despite this technology dating to the early 1990s, there is a need to translate more functional neuroimaging markers in clinical settings since they provide a unique opportunity to examine, in-depth, the brain plasticity changes induced by robotic rehabilitation.

The identification of interacting brain networks during robot-assisted training with multimodal stimulation

Objective.Robot-assisted rehabilitation training is an effective way to assist rehabilitation therapy. So far, various robotic devices have been developed for automatic training of central nervous system following injury. Multimodal stimulation such as visual and auditory stimulus and even virtual reality technology were usually introduced in these robotic devices to improve the effect of rehabilitation training. This may need to be explained from a neurological perspective, but there are few relevant studies.Approach.In this study, ten participants performed right arm rehabilitation training tasks using an upper limb rehabilitation robotic device. The tasks were completed under four different feedback conditions including multiple combinations of visual and auditory components: auditory feedback; visual feedback; visual and auditory feedback (VAF); non-feedback. The functional near-infrared spectroscopy devices record blood oxygen signals in bilateral motor, visual and auditory areas. Using hemoglobin concentration as an indicator of cortical activation, the effective connectivity of these regions was then calculated through Granger causality.Main results.We found that overall stronger activation and effective connectivity between related brain regions were associated with VAF. When participants completed the training task without VAF, the trends in activation and connectivity were diminished.Significance.This study revealed cerebral cortex activation and interacting networks of brain regions in robot-assisted rehabilitation training with multimodal stimulation, which is expected to provide indicators for further evaluation of the effect of rehabilitation training, and promote further exploration of the interaction network in the brain during a variety of external stimuli, and to explore the best sensory combination.

Aphasia improvement without logotherapy during motor neurorehabilitation of post-stroke hemiparesis using virtual reality or modified constraint-induced movement therapy: A retrospective cohort

BACKGROUND

Some research suggests that post-stroke aphasia can recover "on its own", however, there is evidence of a common neural substrate for motor and language systems. We hypothesize, that motor neurorehabilitation of hemiparesis could be related to simultaneous improvement in aphasia.

OBJECTIVE

To measure changes in post-stroke aphasia and its relation with hemiparesis treated with different therapies.

METHODS

Database information (n = 32) on post-stroke hemiparesis (Fugl-Meyer Scale evaluated) managed with virtual reality (VR) versus modified constraint-induced movement therapy (mCIMT) or regular therapy (rPT/OT) was analyzed. None received logotherapy (LT) by appointment at four months.

INCLUSION CRITERIA

< 3 months after the stroke, aphasia severe (Boston Aphasia Intensity Scale), and all three evaluations.

RESULTS

Twenty-one patient records met inclusion criteria (71,4% women and mean age 66,67±3,13 years) who received VR, mCIMT, or rPT/OT (n = 6, 8, and 7, respectively). There was continuous intra-groups improvement in aphasia (p < 0.05), but inter-groups the greater aphasia recovery (p = 0.05) and hemiparesis (p = 0.02) were in VR, with a high correlation in evolution between them (r = 0.73; p = 0.047).

CONCLUSION

High clinical correlation between aphasia, without LT, and hemiparesis evolution during motor neurorehabilitation would support common neural connections stimulation. We will conduct a clinical trial, with a larger sample size to contrast our hypothesis.

Virtual reality for neurorehabilitation: A bibliometric analysis of knowledge structure and theme trends

Background

As an emerging technology, virtual reality (VR) has been broadly applied in the medical field, especially in neurorehabilitation. The growing application of VR therapy promotes an increasing amount of clinical studies. In this paper, we present a bibliometric analysis of the existing studies to reveal the current research hotspots and guide future research directions.

Methods

Articles and reviews on the related topic were retrieved from the Science Citation Index Expanded of Web of Science Core Collection database. VOSviewer and Citespace software were applied to systematically analyze information about publications, countries, institutions, authors, journals, citations, and keywords from the included studies.

Results

A total of 1,556 papers published between 1995 and 2021 were identified. The annual number of papers increased gradually over the past three decades, with a peak publication year in 2021 (n = 276). Countries and institutions from North America and Western European were playing leading roles in publications and total citations. Current hotspots were focused on the effectiveness of VR therapy in cognitive and upper limb motor rehabilitation. The clusters of keywords contained the four targeted neurological diseases of VR, while the burst keywords represented that the latest studies were directed toward more defined types of VR therapy and greater study design.

Conclusions

Our study offers information regarding to the current hotspots and emerging trends in the VR for rehabilitation field. It could guide future research and application of VR therapy in neurorehabilitation.

Revisiting dose and intensity of training: Opportunities to enhance recovery following stroke

PURPOSE

Stroke is a global leading cause of adult disability with survivors often enduring persistent impairments and loss of function. Both intensity and dosage of training appear to be important factors to help restore behavior. However, current practice fails to achieve sufficient intensity and dose of training to promote meaningful recovery. The purpose of this review is to propose therapeutic solutions that can help achieve a higher dose and/or intensity of therapy. Raising awareness of these intensive, high-dose, treatment strategies might encourage clinicians to re-evaluate current practice and optimize delivery of stroke rehabilitation for maximal recovery.

METHODS

Literature that tested and evaluated solutions to increase dose or intensity of training was reviewed. For each therapeutic strategy, we outline evidence of clinical benefit, supporting neurophysiological data (where available) and discuss feasibility of clinical implementation.

RESULTS

Possible therapeutic solutions included constraint induced movement therapy, robotics, circuit therapy, bursts of training, gaming technologies, goal-oriented instructions, and cardiovascular exercise.

CONCLUSION

Our view is that clinicians should evaluate current practice to determine how intensive high-dose training can be implemented to promote greater recovery after stroke.

Virtual Reality Aided Therapy towards Health 4.0: A Two-Decade Bibliometric Analysis

Health 4.0 aligns with Industry 4.0 and encourages the application of the latest technologies to healthcare. Virtual reality (VR) is a potentially significant component of the Health 4.0 vision. Though VR in health care is a popular topic, there is little knowledge of VR-aided therapy from a macro perspective. Therefore, this paper was aimed to explore the research of VR in aiding therapy, thus providing a potential guideline for futures application of therapeutic VR in healthcare towards Health 4.0. A mixed research method was adopted for this research, which comprised the use of a bibliometric analysis (a quantitative method) to conduct a macro overview of VR-aided therapy, the identification of significant research structures and topics, and a qualitative review of the literature to reveal deeper insights. Four major research areas of VR-aided therapy were identified and investigated, i.e., post-traumatic stress disorder (PTSD), anxiety and fear related disorder (A&F), diseases of the nervous system (DNS), and pain management, including related medical conditions, therapies, methods, and outcomes. This study is the first to use VOSviewer, a commonly used software tool for constructing and visualizing bibliometric networks and developed by Center for Science and Technology Studies, Leiden University, the Netherlands, to conduct bibliometric analyses on VR-aided therapy from the perspective of Web of Science core collection (WoSc), which objectively and visually shows research structures and topics, therefore offering instructive insights for health care stakeholders (particularly researchers and service providers) such as including integrating more innovative therapies, emphasizing psychological benefits, using game elements, and introducing design research. The results of this paper facilitate with achieving the vision of Health 4.0 and illustrating a two-decade (2000 to year 2020) map of pre-life of the Health Metaverse.

MRI markers of functional connectivity and tissue microstructure in stroke-related motor rehabilitation: A systematic review

BACKGROUND

Stroke-related disability is a major problem at individual and socio-economic levels. Neuromotor rehabilitation has a key role for its dual action on affected body segment and brain reorganization. Despite its known efficacy in clinical practice, the extent and type of effect at a brain level, mediated by neuroplasticity, are still under question.

OBJECTIVE

To analyze studies applying MRI markers of functional and structural connectivity in patients affected with stroke undergoing motor rehabilitation, and to evaluate the effect of rehabilitation on brain reorganization.

METHODS

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria were applied to select studies applying quantitative non-conventional MRI techniques on patients undergoing motor rehabilitation, both physical and virtual (virtual reality, mental imagery). Literature search was conducted using MEDLINE (via PubMed), Cochrane Central Register of Controlled Trials (CENTRAL), and EMBASE from inception to 30th June 2020.

RESULTS

Forty-one out of 6983 papers were included in the current review. Selected studies are heterogeneous in terms of patient characteristics as well as type, duration and frequency of rehabilitative approach. Neuromotor rehabilitation promotes neuroplasticity, favoring functional recovery of the ipsilesional hemisphere and activation of anatomically and functionally related brain areas in both hemispheres, to compensate for damaged tissue.

CONCLUSIONS

The evidence derived from the analyzed studies supports the positive impact of rehabilitation on brain reorganization, despite the high data heterogeneity. Advanced MRI techniques provide reliable markers of structural and functional connectivity that may potentially aid in helping to implement the most appropriate rehabilitation intervention.

Effects of virtual reality-based motor rehabilitation: a systematic review of fMRI studies

BACKGROUND

The use of virtual reality (VR) as a rehabilitation tool has been shown to induce motor and cognitive improvements in different populations. Functional magnetic resonance imaging (fMRI) has been used to investigate neuroplasticity resulting from these treatments. We hypothesize that VR rehabilitation induces functional improvement and brain changes that can be detected by fMRI.

OBJECTIVE

To systematically review the effects of VR intervention on the cortical reorganization measured by fMRI and associated with functional improvement.

METHODS

We performed a systematic review of studies published between 2005 and 2021. Papers were retrieved from six databases using the following keywords: "motor rehabilitation", "fMRI" and "virtual reality". Case studies, pre-post studies, cross-sectional studies, and randomized controlled trials published were included. Manuscripts were assessed by The NIH Study Quality Assessment Tools to determine their quality.

RESULTS

Twenty-three articles met our eligibility criteria: 18 about VR rehabilitation in stroke and five on other clinical conditions (older adults, cerebral palsy, and Parkinson's disease). Changes in neural patterns of activation and reorganization were revealed in both the ipsilesional and the contralesional hemispheres. Results were located mainly in the primary motor cortex, sensorimotor cortex and supplementary motor area in post-stroke patients in the acute, subacute, and chronic rehabilitation phases, and were associated with functional improvement after VR intervention. Similar effects were observed in older adults and in patients with other neurological diseases with improved performance.

CONCLUSION

Most stroke-related studies showed either restoration to normal or increase of activation patterns or relateralization at/to the ipsilesional hemisphere, with some also reporting a decrease in activity or extent of activation after VR therapy. In general, VR intervention demonstrated evidence of efficacy both in neurological rehabilitation and in performance improvement of older adults, accompanied by fMRI evidence of brain reorganization.

Effect of proprioceptive stimulation using a soft robotic glove on motor activation and brain connectivity in stroke survivors

OBJECTIVE

Soft-robotic-assisted training may improve motor function during post-stroke recovery, but the underlying physiological changes are not clearly understood. We applied a single-session of intensive proprioceptive stimulation to stroke survivors using a soft robotic glove to delineate its short-term influence on brain functional activity and connectivity.

APPROACH

In this study, we utilized task-based and resting-state functional magnetic resonance imaging (fMRI) to characterize the changes in different brain networks following a soft robotic intervention. Nine stroke patients with hemiplegic upper limb engaged in resting-state and motor-task fMRI. The motor tasks comprised two conditions: active movement of fingers (active task) and glove-assisted active movement using a robotic glove (glove-assisted task), both with visual instruction. Each task was performed using bilateral hands simultaneously or the affected hand only. The same set of experiments was repeated following a 30-minute treatment of continuous passive motion (CPM) using a robotic glove.

MAIN RESULTS

On simultaneous bimanual movement, increased activation of supplementary motor area (SMA) and primary motor area (M1) were observed after CPM treatment compared to the pre-treatment condition, both in active and glove-assisted task. However, when performing the tasks solely using the affected hand, the phenomena of increased activity were not observed either in active or glove-assisted task. The comparison of the resting-state fMRI between before and after CPM showed the connectivity of the supramarginal gyrus and SMA was increased in the somatosensory network and salience network.

SIGNIFICANCE

This study demonstrates how passive motion exercise activates M1 and SMA in the post-stroke brain. The effective proprioceptive motor integration seen in bimanual exercise in contrast to the unilateral affected hand exercise suggests that the unaffected hemisphere might reconfigure connectivity to supplement damaged neural networks in the affected hemisphere. The somatosensory modulation rendered by the intense proprioceptive stimulation would affect the motor learning process in stroke survivors.

Neuroplasticity and Motor Rehabilitation in Multiple Sclerosis: A Systematic Review on MRI Markers of Functional and Structural Changes

Background: Motor rehabilitation is routinely used in clinical practice as an effective method to reduce progressive disability gain in multiple sclerosis (MS), but rehabilitation approaches are typically unstandardized, and only few studies have investigated the impact of rehabilitation on brain neuroplasticity. Objective: To summarize and critically analyze studies applying MRI markers of functional connectivity and structural changes to assess the effect of motor rehabilitation on brain neuroplasticity in MS. Methods: Literature search was performed using PubMed and EMBASE, selecting studies having as a subject motor rehabilitation and advanced MRI techniques investigating neuroplasticity in adult patients affected by MS. Results: Seventeen out of 798 papers were selected, of which 5 applied structural MRI (4 diffusion tensor imaging, 1 volumetric measurements), 7 applied functional fMRI (5 task-related fMRI, 2 resting-state fMRI) whereas the remaining 5 applied both structural and functional imaging. Discussion: The considerable data heterogeneity and the small sample sizes characterizing the studies limit interpretation and generalization of the results. Overall, motor rehabilitation promotes clinical improvement, paralleled by positive adaptive brain changes, whose features and extent depend upon different variables, including the type of rehabilitation approach. MRI markers of functional and structural connectivity should be implemented in studies testing the efficacy of motor rehabilitation. They allow for a better understanding of neuroplastic mechanisms underlying rehabilitation-mediated clinical achievements, facilitating the identification of rehabilitation strategies tailored to patients' needs and abilities.

The Route of Motor Recovery in Stroke Patients Driven by Exoskeleton-Robot-Assisted Therapy: A Path-Analysis

Background: Exoskeleton-robot-assisted therapy is known to positively affect the recovery of arm functions in stroke patients. However, there is a lack of evidence regarding which variables might favor a better outcome and how this can be modulated by other factors. Methods: In this within-subject study, we evaluated the efficacy of a robot-assisted rehabilitation system in the recovery of upper limb functions. We performed a path analysis using a structural equation modeling approach in a large sample of 102 stroke patients (age 63.6 ± 13.1 years; 61% men) in the post-acute phase. They underwent 7 weeks of bilateral arm training assisted by an exoskeleton robot combined with a conventional treatment (consisting of simple physical activity together with occupational therapy). The upper extremity section of the Fugl-Meyer (FM-UE) scale at admission was used as a predictor of outcome, whereas age, gender, side of the lesion, days from the event, pain scale, duration of treatment, and number of sessions as mediators. Results: FM-UE at admission was a direct predictor of outcome, as measured by the motricity index of the contralateral upper limb and trunk control test, without any other mediating factors. Age, gender, days from the event, side of lesion, and pain scales were independently associated with outcomes. Conclusions: To the best of our knowledge, this is the first study assessing the relationship between clinical variables and outcomes induced by robot-assisted rehabilitation with a path-analysis model. We define a new route for motor recovery of stroke patients driven by exoskeleton-robot-assisted therapy, highlighting the role of FM-UE at admission as a useful predictor of outcome, although other variables need to be considered in the time-course of disease.

Neuroplasticity mediated by motor rehabilitation in Parkinson's disease: a systematic review on structural and functional MRI markers

Parkinson's disease (PD) is the second most common neurological disease affecting the elderly population. Pharmacological and surgical interventions usually employed for PD treatment show transient effectiveness and are associated with the insurgence of side effects. Therefore, motor rehabilitation has been proposed as a promising supplement in the treatment of PD, reducing the global burden of the disease and improving patients quality of life. The present systematic review aimed to critically analyse the literature concerning MRI markers of brain functional and structural response to motor rehabilitation in PD. Fourteen out of 1313 studies were selected according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria. Despite the limited number of retrieved studies coupled with their heterogeneity prevent ultimate conclusions from being drawn, motor rehabilitation seems to have beneficial effects on PD as measured both with clinical outcomes and MRI derived indices. Interestingly, consistent results seem to indicate that motor rehabilitation acts via a dual mechanism of strengthening cortico-subcortical pathways, restoring movements automaticity, or activating compensatory networks such as the fronto-parietal one. The employment of more advanced and quantitative MRI methods is warranted to establish and validate standardized metrics capable of reliably determining the changes induced by rehabilitative intervention.

Effects of virtual reality intervention on neural plasticity in stroke rehabilitation: a systematic review

OBJECTIVE

To systematically review and examine the current literature regarding the effects of Virtual Reality (VR)-based rehabilitation on neural plasticity changes in stroke survivors.

DATA SOURCES

Six bioscience and engineering databases were searched, including Medline via Ebsco, Embase, PsycINFO, IEEE Explore, Cumulative Index of Nursing and Allied Health, and Scopus.

STUDY SELECTION

Studies reporting on the pre-post assessment of a VR intervention with neural plasticity measures published between 2000-2021 were included.

DATA EXTRACTION

Two independent reviewers conducted study selection, data extraction and quality assessment. Methodological quality of controlled trials was assessed using the Physiotherapy Evidence Database scale. Risk of bias of pre-post intervention and case studies was evaluated using the National Institutes of Health Quality Assessment Tool.

DATA SYNTHESIS

Twenty-seven studies (Total n=232) were included. Seven randomized controlled trials were rated as good quality while the two clinical controlled trials were moderate. Based on the risk of bias assessment, one pre-post study and one case study were graded as good quality, one pre-post study and one case study were poor, the other 14 studies were all at fair. After the VR intervention, main neurophysiological findings across studies include: (1) improved interhemispheric balance, (2) enhanced cortical connectivity, (3) increased cortical mapping of the affected limb muscles, (4) the improved neural plasticity measures were correlated to the enhanced behavior outcomes, (5) increased activation of regions in frontal cortex and (6) the mirror neuron system may be involved.

CONCLUSIONS

Virtual reality induced changes in neural plasticity for stroke survivors. Positive correlations between the neural plasticity changes and functional recovery elucidates the mechanisms of VR's therapeutic effects in stroke rehabilitation. This review prompts systematic understanding of the neurophysiological mechanisms of VR-based stroke rehabilitation and summarizes the emerging evidence for ongoing innovation of VR systems and application in stroke rehabilitation.

The Untapped Potential of Virtual Reality in Rehabilitation of Balance and Gait in Neurological Disorders

Dynamic systems theory transformed our understanding of motor control by recognizing the continual interaction between the organism and the environment. Movement could no longer be visualized simply as a response to a pattern of stimuli or as a demonstration of prior intent; movement is context dependent and is continuously reshaped by the ongoing dynamics of the world around us. Virtual reality is one methodological variable that allows us to control and manipulate that environmental context. A large body of literature exists to support the impact of visual flow, visual conditions, and visual perception on the planning and execution of movement. In rehabilitative practice, however, this technology has been employed mostly as a tool for motivation and enjoyment of physical exercise. The opportunity to modulate motor behavior through the parameters of the virtual world is often ignored in practice. In this article we present the results of experiments from our laboratories and from others demonstrating that presenting particular characteristics of the virtual world through different sensory modalities will modify balance and locomotor behavior. We will discuss how movement in the virtual world opens a window into the motor planning processes and informs us about the relative weighting of visual and somatosensory signals. Finally, we discuss how these findings should influence future treatment design.

Control Modification of Grasp Force Covaries Agency and Performance on Rigid and Compliant Surfaces

This study investigated how modifications in the display of a computer trace under user control of grasp forces can co-modulate agency (perception of control) and performance of grasp on rigid and compliant surfaces. We observed positive correlation (p < 0.01) between implicit agency, measured from time-interval estimation for intentional binding, and grasp performance, measured by force-tracking error, across varying control modes for each surface type. The implications of this work are design directives for cognition-centered device interfaces for rehabilitation of grasp after neurotraumas such as spinal cord and brain injuries while considering if grasp interaction is rigid or compliant. These device interfaces should increase user integration to virtual reality training and powered assistive devices such as exoskeletons and prostheses. The modifications in control modes for this study included changes in force magnitude, addition of mild noise, and a measure of automation. Significant differences (p < 0.001) were observed for each surface type across control modes with metrics for implicit agency, performance, and grasp control efficiency. Explicit agency, measured from user survey responses, did not exhibit significant variations in this study, suggesting implicit measures of agency are needed for identifying co-modulation with grasp performance. Grasp on the compliant surface resulted in greater dependence of performance on agency and increases in agency and performance with the addition of mild noise. Noise in conjunction with perceived freedom at a flexible surface may have amplified visual feedback responses. Introducing automation in control decreased agency and performance for both surfaces, suggesting the value in continuous user control of grasp. In conclusion, agency and performance of grasp can be co-modulated across varying modes of control, especially for compliant grasp actions. Future studies should consider reliable measures of implicit agency, including physiological recordings, to automatically adapt rehabilitation interfaces for better cognitive engagement and to accelerate functional outcomes.

Virtual Rehabilitation of the Paretic Hand and Arm in Persons With Stroke: Translation From Laboratory to Rehabilitation Centers and the Patient's Home

The anatomical and physiological heterogeneity of strokes and persons with stroke, along with the complexity of normal upper extremity movement make the possibility that any single treatment approach will become the definitive solution for all persons with upper extremity hemiparesis due to stroke unlikely. This situation and the non-inferiority level outcomes identified by many studies of virtual rehabilitation are considered by some to indicate that it is time to consider other treatment modalities. Our group, among others, has endeavored to build on the initial positive outcomes in studies of virtual rehabilitation by identifying patient populations, treatment settings and training schedules that will best leverage virtual rehabilitation's strengths. We feel that data generated by our lab and others suggest that (1) persons with stroke may adapt to virtual rehabilitation of hand function differently based on their level of impairment and stage of recovery and (2) that less expensive, more accessible home based equipment seems to be an effective alternative to clinic based treatment that justifies continued optimism and study.

Altered Prefrontal-Basal Ganglia Effective Connectivity in Patients With Poststroke Cognitive Impairment

We investigated the association between poststroke cognitive impairment and a specific effective network connectivity in the prefrontal-basal ganglia circuit. The resting-state effective connectivity of this circuit was modeled by employing spectral dynamic causal modeling in 11 poststroke patients with cognitive impairment (PSCI), 8 poststroke patients without cognitive impairment (non-PSCI) at baseline and 3-month follow-up, and 28 healthy controls. Our results showed that different neuronal models of effective connectivity in the prefrontal-basal ganglia circuit were observed among healthy controls, non-PSCI, and PSCI patients. Additional connected paths (extra paths) appeared in the neuronal models of stroke patients compared with healthy controls. Moreover, changes were detected in the extra paths of non-PSCI between baseline and 3-month follow-up poststroke, indicating reorganization in the ipsilesional hemisphere and suggesting potential compensatory changes in the contralesional hemisphere. Furthermore, the connectivity strengths of the extra paths from the contralesional ventral anterior nucleus of thalamus to caudate correlated significantly with cognitive scores in non-PSCI and PSCI patients. These suggest that the neuronal model of effective connectivity of the prefrontal-basal ganglia circuit may be sensitive to stroke-induced cognitive decline, and it could be a biomarker for poststroke cognitive impairment 3 months poststroke. Importantly, contralesional brain regions may play an important role in functional compensation of cognitive decline.

Enhancing Brain Plasticity to Promote Stroke Recovery

Stroke disturbs both the structural and functional integrity of the brain. The understanding of stroke pathophysiology has improved greatly in the past several decades. However, effective therapy is still limited, especially for patients who are in the subacute or chronic phase. Multiple novel therapies have been developed to improve clinical outcomes by improving brain plasticity. These approaches either focus on improving brain remodeling and restoration or on constructing a neural bypass to avoid brain injury. This review describes emerging therapies, including modern rehabilitation, brain stimulation, cell therapy, brain-computer interfaces, and peripheral nervous transfer, and highlights treatment-induced plasticity. Key evidence from basic studies on the underlying mechanisms is also briefly discussed. These insights should lead to a deeper understanding of the overall neural circuit changes, the clinical relevance of these changes in stroke, and stroke treatment progress, which will assist in the development of future approaches to enhance brain function after stroke.

Acceptability of a Mobile Phone-Based Augmented Reality Game for Rehabilitation of Patients With Upper Limb Deficits from Stroke: Case Study

Background

Upper limb functional deficits are common after stroke and result from motor weakness, ataxia, spasticity, spatial neglect, and poor stamina. Past studies employing a range of commercial gaming systems to deliver rehabilitation to stroke patients provided short-term efficacy but have not yet demonstrated whether or not those games are acceptable, that is, motivational, comfortable, and engaging, which are all necessary for potential adoption and use by patients.

Objective

The goal of the study was to assess the acceptability of a smartphone-based augmented reality game as a means of delivering stroke rehabilitation for patients with upper limb motor function loss.

Methods

Patients aged 50 to 70 years, all of whom experienced motor deficits after acute ischemic stroke, participated in 3 optional therapy sessions using augmented reality therapeutic gaming over the course of 1 week, targeting deficits in upper extremity strength and range of motion. After completion of the game, we administered a 16-item questionnaire to the patients to assess the game’s acceptability; 8 questions were answered by rating on a scale from 1 (very negative experience) to 5 (very positive experience); 8 questions were qualitative.

Results

Patients (n=5) completed a total of 23 out of 45 scheduled augmented reality game sessions, with patient fatigue as the primary factor for uncompleted sessions. Each patient consented to 9 potential game sessions and completed a mean of 4.6 (SE 1.3) games. Of the 5 patients, 4 (80%) completed the questionnaire at the end of their final gaming session. Of note, patients were motivated to continue to the end of a given gaming session (mean 4.25, 95% CI 3.31-5.19), to try other game-based therapies (mean 3.75, 95% CI 2.81-4.69), to do another session (mean 3.50, 95% CI 2.93-4.07), and to perform other daily rehabilitation exercises (mean 3.25, 95% CI 2.76-3.74). In addition, participants gave mean scores of 4.00 (95% CI 2.87-5.13) for overall experience; 4.25 (95% CI 3.31-5.19) for comfort; 3.25 (95% CI 2.31-4.19) for finding the study fun, enjoyable, and engaging; and 3.50 (95% CI 2.52-4.48) for believing the technology could help them reach their rehabilitation goals. For each of the 4 patients, their reported scores were statistically significantly higher than those generated by a random sampling of values (patient 1: P=.04; patient 2: P=.04; patient 4: P=.004; patient 5: P=.04).

Conclusions

Based on the questionnaire scores, the patients with upper limb motor deficits following stroke who participated in our case study found our augmented reality game motivating, comfortable, engaging, and tolerable. Improvements in augmented reality technology motivated by this case study may one day allow patients to work with improved versions of this therapy independently in their own home. We therefore anticipate that smartphone-based augmented reality gaming systems may eventually provide useful postdischarge self-treatment as a supplement to professional therapy for patients with upper limb deficiencies from stroke.

Virtual reality training enhances gait poststroke: a systematic review and meta-analysis

Virtual reality (VR)-based interventions are gaining widespread attention for managing neurological disorders such as stroke. A metastatistical consensus regarding the intervention is strongly warranted. In this study, we attempt to address this gap in the literature and provide the current state of evidence for the effects of VR on gait performance. We conducted both between- and within-group meta-analyses to provide a state of evidence for VR. Moreover, we conducted a search adhering to PRISMA guidelines on nine databases. Out of 1866 records, 32 studies involving a total of 809 individuals were included in this review. Considering all included studies, significant enhancements in gait parameters were observed with VR-based interventions compared with conventional therapy. A between-group meta-analysis reported beneficial significant medium effects of VR training on cadence (Hedge's g = 0.55), stride length ((STrL; Hedge's g = 0.46), and gait speed (Hedge's g = 0.30). Similarly, a within-group meta-analysis further revealed positive medium effects of VR on cadence (Hedge's g = 0.76), STrL (Hedge's g = 0.61), and gait speed (Hedge's g = 0.69). Additional subgroup analyses revealed beneficial effects of joint application of VR and robot-assisted gait training on gait speed (Hedge's g = 0.50). Collectively, findings from this review provide evidence for the effectiveness of VR-based gait training for stroke survivors.

Disproportionate positive feedback facilitates sense of agency and performance for a reaching movement task with a virtual hand

This study investigated the generalized effects of positive feedback (PF) versus negative feedback (NF) during training on performance and sense of agency for a reach-to-touch task with a virtual hand. Virtual reality (VR) is increasingly employed for rehabilitation after neuromuscular traumas such as stroke and spinal cord injury. However, VR methods still need to be optimized for greater effectiveness and engagement to increase rates of clinical retention. In this study, we observed that training with disproportionate PF subsequently produced greater reaching performance (minimizing path length) and greater agency (perception of control) than with disproportionate NF. During PF training, there was also progressive increase in agency, but conversely a decrease in performance. Thus, the increase in performance after training may not be due to positively bolstered learning, but rather priming higher confidence reflected in greater agency. Agency was positively measured as compression in perceived time-intervals between the action of touch to a sound consequence, as standard with intentional binding paradigms. Positive feedback desirably increased agency (~180 msec) and reduced path length (1.8 cm) compared to negative feedback, which itself showed insignificant, or neutral, effects. Future investigations into optimizing virtual reality paradigms for neuromotor rehabilitation should consider agency as a driving factor for performance. These studies may serve to optimize how feedback is better presented with performance results for complex motor learning. Investigators should also ponder how personal characteristics, both cognitive and physical, may further affect sensitivity to feedback and the rate of neuromotor rehabilitation.

Agency and Performance of Reach-to-Grasp With Modified Control of a Virtual Hand: Implications for Rehabilitation

This study investigated how modified control of a virtual hand executing reach-to-grasp affects functional performance and agency (perception of control). The objective of this work was to demonstrate positive relationships between reaching performance and grasping agency and motivate greater consideration of agency in movement rehabilitation. We hypothesized that agency and performance have positive correlation across varying control modes of the virtual hand. In this study, each participant controlled motion of a virtual hand through motion of his or her own hand. Control of the virtual hand was modified according to a specific control mode. Each mode involved the virtual hand moving at a modified speed, having noise, or including a level of automation. These specific modes represent potential control features to adapt for a rehabilitation device such as a prosthetic arm and hand. In this study, significant changes in agency and performance were observed across the control modes. Overall, a significant positive relationship (p < 0.001) was observed between the primary performance metric of reach (tracking a minimum path length trajectory) and an implicit measurement of agency (intentional binding). Intentional binding was assessed through participant perceptions of time-intervals between grasp contact and a sound event. Other notable findings include improved movement efficiency (increased smoothness, reduced acceleration) during expression of higher agency and shift toward greater implicit versus explicit agency with higher control speed. Positively relating performance and agency incentivizes control adaptation of powered movement devices, such as prostheses or exoskeletons, to maximize both user engagement and functional performance. Agency-based approaches may foster user-device integration at a cognitive level and facilitate greater clinical retention of the device. Future work should identify robust and automated methods to adapt device control for increased agency. Objectives include how virtual reality (VR) may identify optimal control of real-world devices and assessing real-time agency from neurophysiological signals.

Effects of Virtual Reality-Based Rehabilitation on Burned Hands: A Prospective, Randomized, Single-Blind Study

Hands are the most frequent burn injury sites. Appropriate rehabilitation is essential to ensure good functional recovery. Virtual reality (VR)-based rehabilitation has proven to be beneficial for the functional recovery of the upper extremities. We investigated and compared VR-based rehabilitation with conventional rehabilitation (CON) in patients with burned hands. Fifty-seven patients were randomized into a VR or CON group. Each intervention was applied to the affected hand for four weeks, and clinical and functional variables were evaluated. Hand function was evaluated before intervention and four weeks after intervention using the Jebsen-Taylor hand function test (JTT), Grasp and Pinch Power Test, Purdue Pegboard test (PPT), and Michigan Hand Outcomes Questionnaire (MHQ). The JTT scores for picking up small objects and the MHQ scores for hand function, functional ADL, work, pain, aesthetics, and patient satisfaction were significantly higher in the VR group than in the CON group (p < 0.05). The results suggested that VR-based rehabilitation is likely to be as effective as conventional rehabilitation for recovering function in a burned hand. VR-based rehabilitation may be considered as a treatment option for patients with burned hands.

Data on a new neurorehabilitation approach targeting functional recovery in stroke patients

Robotic-assisted devices are known to positively affect the recovery of one specific motor effector after stroke. However, it has widely been reported that the functional status of patients is only partially ameliorated after application of this kind of advanced treatment.

Here, data about the effect of a new rehabilitation approach has been described in a large population of stroke patients. We sought to validate an integrated rehabilitation system for stroke (IRSS) patients, which is composed of a set of robotic-assisted tools aimed at recovering the entire body.

We evaluated the motor recovery in 84 stroke patients equally divided into experimental and control groups to assess the difference between IRSS approach and conventional rehabilitation treatment. We found that IRSS induced a significant improvement as measured by functional neurological scales, such as the barthel index and functional independence measure.

The data provided in this article will assist therapists and physicians working for developing new rehabilitation protocols more focused on a holistic functional recovery approach. The data are available at Mendeley Data, https://doi.org/10.17632/wptmgm7zk2.1.

Virtual Reality and Noninvasive Brain Stimulation in Stroke: How Effective Is Their Combination for Upper Limb Motor Improvement?-A Meta-Analysis

BACKGROUND

Efforts to augment post-stroke upper limb (UL) motor improvement include the use of newer interventions such as noninvasive brain stimulation (NIBS) and task practice in virtual reality environments (VEs). Despite increasing interest in using a combination of these 2 interventions, the effectiveness of this combination to enhance UL motor improvement outcomes has not been examined.

OBJECTIVE

To evaluate the effectiveness of a combination of NIBS and task practice in a VE to augment post-stroke UL motor improvement.

METHODS

We conducted a systematic search of the published literature using standard methodology. The Down and Black checklist and the Physiotherapy Evidence Database Research Organization Scale were used to assess study quality. We compared changes in UL impairment and activity levels between active stimulation and sham or other interventions using standardized mean differences and derived a summary effect size.

RESULTS

We retrieved 5 studies that examined the role of a combination of NIBS and task practice in a VE to optimize UL motor improvement. These 5 studies included 3 randomized controlled trials, 1 cross-sectional study, and 1 crossover study. There was level 1a evidence that the combination was beneficial in subacute stroke. There was level 1b evidence that provision of real stimulation was not superior to sham stimulation in chronic stroke. Effect sizes favoring the combination were moderate for improvements in UL impairment and small for activity levels.

CONCLUSIONS

Preliminary evidence supports the effectiveness of this combination in subacute stroke. Emergent questions need to be addressed to derive maximum benefit of this combination to augment post-stroke UL motor improvement.

LEVEL OF EVIDENCE

I.

Brain Computer Interfaces in Rehabilitation Medicine

One innovation currently influencing physical medicine and rehabilitation is brain-computer interface (BCI) technology. BCI systems used for motor control record neural activity associated with thoughts, perceptions, and motor intent; decode brain signals into commands for output devices; and perform the user's intended action through an output device. BCI systems used for sensory augmentation transduce environmental stimuli into neural signals interpretable by the central nervous system. Both types of systems have potential for reducing disability by facilitating a user's interaction with the environment. Investigational BCI systems are being used in the rehabilitation setting both as neuroprostheses to replace lost function and as potential plasticity-enhancing therapy tools aimed at accelerating neurorecovery. Populations benefitting from motor and somatosensory BCI systems include those with spinal cord injury, motor neuron disease, limb amputation, and stroke. This article discusses the basic components of BCI for rehabilitation, including recording systems and locations, signal processing and translation algorithms, and external devices controlled through BCI commands. An overview of applications in motor and sensory restoration is provided, along with ethical questions and user perspectives regarding BCI technology.

Efficacy of Virtual Reality Combined With Real Instrument Training for Patients With Stroke: A Randomized Controlled Trial

OBJECTIVE

To investigate the efficacy of real instrument training in virtual reality (VR) environment for improving upper-extremity and cognitive function after stroke.

DESIGN

Single-blind, randomized trial.

SETTING

Medical center.

PARTICIPANTS

Enrolled subjects (N=31) were first-episode stroke, assessed for a period of 6 months after stroke onset; age between 20 and 85 years; patients with unilateral paralysis and a Fugl-Meyer assessment upper-extremity scale score >18.

INTERVENTIONS

Both groups were trained 30 minutes per day, 3 days a week, for 6 weeks, with the experimental group performing the VR combined real instrument training and the control group performing conventional occupational therapy.

MAIN OUTCOME MEASURES

Manual Muscle Test, modified Ashworth scale, Fugl-Meyer upper motor scale, hand grip, Box and Block, 9-Hole Peg Test (9-HPT), Korean Mini-Mental State Examination, and Korean-Montreal Cognitive Assessment.

RESULTS

The experimental group showed greater therapeutic effects in a time-dependent manner than the control group, especially on the motor power of wrist extension, spasticity of elbow flexion and wrist extension, and Box and Block Tests. Patients in the experimental group, but not the control group, also showed significant improvements on the lateral, palmar, and tip pinch power, Box and Block, and 9-HPTs from before to immediately after training. Significantly greater improvements in the tip pinch power immediately after training and spasticity of elbow flexion 4 weeks after training completion were noted in the experimental group.

CONCLUSIONS

VR combined real instrument training was effective at promoting recovery of patients' upper-extremity and cognitive function, and thus may be an innovative translational neurorehabilitation strategy after stroke.

Multi-Sensorimotor Training Improves Proprioception and Balance in Subacute Stroke Patients: A Randomized Controlled Pilot Trial

Introduction: The objective was to determine whether advanced rehabilitation therapy combined with conventional rehabilitation therapy consisting of sensorimotor exercises would be superior to usual treadmill training for proprioception variation and balance ability in subacute stroke patients.

Methods: Thirty subjects (post-stroke time period: 3.96 ± 1.19 months) were randomly assigned to either a multi-sensorimotor training group (n = 19) or a treadmill training group (n = 18). Both groups first performed conventional physical therapy for 30 min, after which the multi-sensorimotor training group performed multi-sensorimotor training for 30 min, and the treadmill training group performed treadmill gait training for 30 min. Both groups performed the therapeutic interventions 5 days per week for 8 weeks. The primary outcome (proprioception variation) was evaluated using an acryl panel and electrogoniometer. The secondary outcome (balance ability) was measured using the Biodex Balance system before intervention and after 8 weeks.

Results: The multi-sensorimotor training and treadmill training groups showed significant improvement in proprioception variation and balance (overall, A-P and M-L) (all P < 0.05). In particular, the multi-sensorimotor training group showed more significant differences in proprioception variation (P = 0.002) and anterior-posterior (A-P) balance ability (P = 0.033) than the treadmill training group.

Conclusions: The multi-sensorimotor training program performed on multiple types of sensory input had a beneficial effect on proprioception sense in the paretic lower limb and A-P balance. A large-scale randomized controlled study is needed to prove the effect of this training.

Clinical Trial Registration:https://cris.nih.go.kr/cris/, identifier KCT0003097.

Exoskeleton-Robot Assisted Therapy in Stroke Patients: A Lesion Mapping Study

Background: Technology-supported rehabilitation is emerging as a solution to support therapists in providing a high-intensity, repetitive and task-specific treatment, aimed at improving stroke recovery. End-effector robotic devices are known to positively affect the recovery of arm functions, however there is a lack of evidence regarding exoskeletons. This paper evaluates the impact of cerebral lesion load on the response to a validated robotic-assisted rehabilitation protocol.

Methods: Fourteen hemiparetic patients were assessed in a within-subject design (age 66.9 ± 11.3 years; 10 men and 4 women). Patients, in post-acute phase, underwent 7 weeks of bilateral arm training assisted by an exoskeleton robot combined with a conventional treatment (consisting of simple physical activity together with occupational therapy). Clinical and neuroimaging evaluations were performed immediately before and after rehabilitation treatments. Fugl-Meyer (FM) and Motricity Index (MI) were selected to measure primary outcomes, i.e., motor function and strength. Functional independance measure (FIM) and Barthel Index were selected to measure secondary outcomes, i.e., daily living activities. Voxel-based lesion symptom mapping (VLSM) was used to determine the degree of cerebral lesions associated with motor recovery.

Results: Robot-assisted rehabilitation was effective in improving upper limb motor function recovery, considering both primary and secondary outcomes. VLSM detected that lesion load in the superior region of the corona radiata, internal capsule and putamen were significantly associated with recovery of the upper limb as defined by the FM scores (p-level < 0.01).

Conclusions: The probability of functional recovery from stroke by means of exoskeleton robotic rehabilitation relies on the integrity of specific subcortical regions involved in the primary motor pathway. This is consistent with previous evidence obtained with conventional neurorehabilitation approaches.

The Activation of the Mirror Neuron System during Action Observation and Action Execution with Mirror Visual Feedback in Stroke: A Systematic Review

Objective

To evaluate the concurrent and training effects of action observation (AO) and action execution with mirror visual feedback (MVF) on the activation of the mirror neuron system (MNS) and its relationship with the activation of the motor cortex in stroke individuals.

Methods

A literature search using CINAHL, PubMed, PsycINFO, Medline, Web of Science, and SCOPUS to find relevant studies was performed.

Results

A total of 19 articles were included. Two functional magnetic resonance imaging (fMRI) studies reported that MVF could activate the ipsilesional primary motor cortex as well as the MNS in stroke individuals, whereas two other fMRI studies found that the MNS was not activated by MVF in stroke individuals. Two clinical trials reported that long-term action execution with MVF induced a shift of activation toward the ipsilesional hemisphere. Five fMRI studies showed that AO activated the MNS, of which, three found the activation of movement-related areas. Five electroencephalography (EEG) studies demonstrated that AO or MVF enhanced mu suppression over the sensorimotor cortex.

Conclusions

MVF may contribute to stroke recovery by revising the interhemispheric imbalance caused by stroke due to the activation of the MNS. AO may also promote motor relearning in stroke individuals by activating the MNS and motor cortex.

Intensity- and Duration-Adaptive Functional Electrical Stimulation Using Fuzzy Logic Control and a Linear Model for Dropfoot Correction

Functional electrical stimulation (FES) is important in gait rehabilitation for patients with dropfoot. Since there are time-varying velocities during FES-assisted walking, it is difficult to achieve a good movement performance during walking. To account for the time-varying walking velocities, seven poststroke subjects were recruited and fuzzy logic control and a linear model were applied in FES-assisted walking to enable intensity- and duration-adaptive stimulation (IDAS) for poststroke subjects with dropfoot. In this study, the performance of IDAS was evaluated using kinematic data, and was compared with the performance under no stimulation (NS), FES-assisted walking triggered by heel-off stimulation (HOS), and speed-adaptive stimulation. A larger maximum ankle dorsiflexion angle in the IDAS condition than those in other conditions was observed. The ankle plantar flexion angle in the IDAS condition was similar to that of normal walking. Improvement in the maximum ankle dorsiflexion and plantar flexion angles in the IDAS condition could be attributed to having the appropriate stimulation intensity and duration. In summary, the intensity- and duration-adaptive controller can attain better movement performance and may have great potential in future clinical applications.