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Stroke is a devastating condition that may cause upper limb paralysis. Robotic rehabilitation with self-initiated and assisted movements is a promising technology that could help restore upper limb function. Previous studies have established that the tongue motion can be used to communicate human intent and control a rehabilitation robot/assistive device. The goal of this study was to evaluate a tongue-operated exoskeleton system (TDS-KA), which we have developed for upper limb rehabilitation. We adopted a tongue-operated assistive technology, called the tongue drive system (TDS), and interfaced it with the exoskeleton KINARM. We also developed arm reaching and tracking tasks, controlled by different tongue operation modes, for training and evaluation of arm motor function. Arm reaching and tracking tasks were tested in 10 healthy participants (seven males and three females, 23-60 years) and two female stroke survivors with upper extremity impairment (32 and 58 years). All healthy and two stroke participants successfully performed the tasks. One stroke subject demonstrated a clinically significant improvement in Fugl-Meyer upper extremity score after practicing the tasks in six 3-h sessions. We conclude that the TDS-KA system can accurately translate tongue commands to exoskeleton arm movements, quantify the function of the arm, and perform rehabilitation training.

Background . Controlled whole-body vibration (CWBV) training has been applied to people with stroke. However, it remains inconclusive if CWBV reduces fall risk in this population. Objective . To (1) assess the immediate and retention effects of CWBV training on fall risk factors in people at postacute and chronic stages of stroke and (2) examine if CWBV dosage is correlated with the effect size (ES) for 3 fall risk factors: body balance, functional mobility, and knee strength. Methods . Twelve randomized controlled trials were included. ES was calculated as the standardized mean difference, and meta-analyses were completed using a random-effects model. Results . CWBV training may lead to improved balance and mobility immediately after training (ES = 0.27, P = .03 for balance; ES = 0.34, P = .02 for mobility) but not at the 3-month follow-up test (ES = 0.02, P = .89 for balance; ES = 0.70, P = .11 for mobility). CWBV affects knee strength capacity with mild ES (ES = 0.08 and 0.11, respectively, for immediate and retention effect; P ≥ .68 for both). Metaregression indicated that the immediate ES is strongly correlated with training dosage for balance ( r = 0.649; P = .029) and mobility ( r = 0.785; P = .036). Conclusions . CWBV training may benefit balance and mobility immediately, but the training effect may not persist among people with stroke. Additionally, the CWBV dosage correlates with the ES for body balance and mobility. More high-quality studies are needed to determine the retention effects of CWBV training.

Stroke survivors with severe upper limb (UL) impairment face years of therapy to recover function. Robot-assisted therapy (RT) is increasingly used in the field for goal-oriented rehabilitation as a means to improve function in ULs. To be used effectively for wrist and hand therapy, the current RT systems require the patient to have a minimal active range of movement in the UL, and those that do not have active voluntary movement cannot use these systems. We have overcome this limitation by harnessing tongue motion to allow patients to control a robot using synchronous tongue and hand movement. This novel RT device combines a commercially available UL exoskeleton, the Hand Mentor, and our custom-designed Tongue Drive System as its controller. We conducted a proof-of-concept study on six nondisabled participants to evaluate the system usability and a case series on three participants with movement limitations from poststroke hemiparesis. Data from two stroke survivors indicate that for patients with chronic, moderate UL impairment following stroke, a 15-session training regimen resulted in modest decreases in impairment, with functional improvement and improved quality of life. The improvement met the standard of minimal clinically important difference for activities of daily living, mobility, and strength assessments.

Brain areas within the motor system interact directly or indirectly during motor-imagery and motor-execution tasks. These interactions and their functionality can change following stroke and recovery. How brain network interactions reorganize and recover their functionality during recovery and treatment following stroke are not well understood. To contribute to answering these questions, we recorded blood oxygenation-level dependent (BOLD) functional magnetic resonance imaging (fMRI) signals from 10 stroke survivors and evaluated dynamical causal modeling (DCM)-based effective connectivity among three motor areas: primary motor cortex (M1), pre-motor cortex (PMC) and supplementary motor area (SMA), during motor-imagery and motor-execution tasks. We compared the connectivity between affected and unaffected hemispheres before and after mental practice and combined mental practice and physical therapy as treatments. The treatment (intervention) period varied in length between 14 to 51 days but all patients received the same dose of 60 h of treatment. Using Bayesian model selection (BMS) approach in the DCM approach, we found that, after intervention, the same network dominated during motor-imagery and motor-execution tasks but modulatory parameters suggested a suppressive influence of SM A on M1 during the motor-imagery task whereas the influence of SM A on M1 was unrestricted during the motor-execution task. We found that the intervention caused a reorganization of the network during both tasks for unaffected as well as for the affected hemisphere. Using Bayesian model averaging (BMA) approach, we found that the intervention improved the regional connectivity among the motor areas during both the tasks. The connectivity between PMC and M1 was stronger in motor-imagery tasks whereas the connectivity from PMC to M1, SM A to M1 dominated in motor-execution tasks. There was significant behavioral improvement (p = 0.001) in sensation and motor movements because of the intervention as reflected by behavioral Fugl-Meyer (FMA) measures, which were significantly correlated (p = 0.05) with a subset of connectivity. These findings suggest that PMC and M1 play a crucial role during motor-imagery as well as during motor-execution task. In addition, M1 causes more exchange of causal information among motor areas during a motor-execution task than during a motor-imagery task due to its interaction with SM A. This study expands our understanding of motor network involved during two different tasks, which are commonly used during rehabilitation following stroke. A clear understanding of the effective connectivity networks leads to a better treatment in helping stroke survivors regain motor ability.

Objective: Constraint-induced movement therapy (CIMT) has been shown to improve upper extremity voluntary movement and change cortical movement representation after stroke. Direct comparison of the differential degree of cortical reorganization according to chronicity in stroke subjects receiving CIMT has not been performed and was the purpose of this study. We hypothesized that a higher degree of cortical reorganization would occur in the early (less than 9 months post-stroke) compared to the late group (more than 12 months post-stroke)., Methods: 17 early and 9 late subjects were enrolled. Each subject was evaluated using transcranial magnetic stimulation (TMS) and the Wolf Motor Function Test (WMFT) and received CIMT for 2 weeks., Results: The early group showed greater improvement in WMFT compared with the late group. TMS motor maps showed persistent enlargement in both groups but the late group trended toward more enlargement. The map shifted posteriorly in the late stroke group. The main limitation was the small number of TMS measures that could be acquired due to high motor thresholds, particularly in the late group., Conclusion: CIMT appears to lead to greater improvement in motor function in the early phase after stroke. Greater cortical reorganization in map size and position occurred in the late group in comparison., Significance: The contrast between larger functional gains in the early group vs larger map changes in the late group may indicate that mechanisms of recovery change over the several months following stroke or that map changes are a time-dependent epiphenomenon.

Study Design: Systematic review and meta-analysis., Introduction: Prior reviews on the effects of anodal transcranial direct current stimulation (a-tDCS) have shown the effectiveness of a-tDCS on corticomotor excitability and motor function in healthy individuals but nonsignificant effect in subjects with stroke., Purpose: To summarize and evaluate the evidence for the efficacy of a-tDCS in the treatment of upper limb motor impairment after stroke., Methods: A meta-analysis of randomized controlled trials that compared a-tDCS with placebo and change from baseline., Results: A pooled analysis showed a significant increase in scores in favor of a-tDCS (standard mean difference [SMD]=0.40, 95% confidence interval [CI]=0.10-0.70, p=0.010, compared with baseline). A similar effect was observed between a-tDCS and sham (SMD=0.49, 95% CI=0.18-0.81, p=0.005)., Conclusion: This meta-analysis of eight randomized placebo-controlled trials provides further evidence that a-tDCS may benefit motor function of the paretic upper limb in patients suffering from chronic stroke., Level of Evidence: Level 1a., (Published by Elsevier Inc.)

Background: At 6 months poststroke, most patients cannot incorporate their affected hand into daily activities, which in turn is likely to reduce their perceived quality of life., Objective: This preliminary study explored change in patient-reported, health-related quality of life associated with robotic-assisted therapy combined with reduced therapist-supervised training., Design and Setting: A single-blind, multi-site, randomized clinical trial was conducted., Participants: Seventeen individuals who were 3 to 9 months poststroke participated., Intervention: Sixty hours of therapist-supervised repetitive task practice (RTP) was compared with 30 hours of RTP combined with 30 hours of robotic-assisted therapy., Measurements: Participants completed the Stroke Impact Scale (SIS) at baseline, immediately postintervention, and 2 months postintervention. Change in SIS score domains was assessed in a mixed model analysis., Results: The combined therapy group had a greater increase in rating of mood from preintervention to postintervention, and the RTP-only group had a greater increase in rating of social participation from preintervention to follow-up. Both groups had statistically significant improvement in activities of daily living and instrumental activities of daily living scores from preintervention to postintervention. Both groups reported significant improvement in hand function postintervention and at follow-up, and the magnitude of these changes suggested clinical significance. The combined therapy group had significant improvements in stroke recovery rating postintervention and at follow-up, which appeared clinically significant; this also was true for stroke recovery rating from preintervention to follow-up in the RTP-only group. LIMITATIONS OUTCOMES: of 30 hours of RTP in the absence of robotic-assisted therapy remain unknown., Conclusion: Robotic-assisted therapy may be an effective alternative or adjunct to the delivery of intensive task practice interventions to enhance hand function recovery in patients with stroke.

Background: A promising paradigm in human neuroimaging is the study of slow (<0.1 Hz) spontaneous fluctuations in the hemodynamic response measured by functional magnetic resonance imaging (fMRI). Spontaneous activity (i.e., resting state) refers to activity that cannot be attributed to specific inputs or outputs, that is, activity intrinsically generated by the brain., Method: This article presents pilot data examining neural connectivity in patients with poststroke hemiparesis before and after 3 weeks of upper extremity rehabilitation in the Accelerated Skill Acquisition Program (ASAP). Resting-state fMRI data acquired pre and post therapy were analyzed using an exploratory adaptation of structural equation modeling (SEM) to evaluate therapy-related changes in motor network effective connectivity., Results: Each ASAP patient showed behavioral improvement. ASAP patients also showed increased influence of the affected hemisphere premotor cortex (a-PM) upon the unaffected hemisphere premotor cortex (u-PM) following therapy. The influence of a-PM on affected hemisphere primary motor cortex (a-M1) also increased with therapy for 3 of 5 patients, including those with greatest behavioral improvement., Conclusions: Our findings suggest that network analyses of resting-state fMRI constitute promising tools for functional characterization of functional brain disorders, for intergroup comparisons, and potentially for assessing effective connectivity within single subjects; all of which have important implications for stroke rehabilitation.

Background: Constraint-induced movement therapy (CIMT) has received considerable attention as an intervention to enhance motor recovery and cortical reorganization after stroke., Objective: The present study represents the first multi-center effort to measure cortical reorganization induced by CIMT in subjects who are in the subacute stage of recovery., Methods: A total of 30 stroke subjects in the subacute phase (>3 and <9 months poststroke) were recruited and randomized into experimental (receiving CIMT immediately after baseline evaluation) and control (receiving CIMT after 4 months) groups. Each subject was evaluated using transcranial magnetic stimulation (TMS) at baseline, 2 weeks after baseline, and at 4-month follow-up (ie, after CIMT in the experimental groups and before CIMT in the control groups). The primary clinical outcome measure was the Wolf Motor Function Test., Results: Both experimental and control groups demonstrated improved hand motor function 2 weeks after baseline. The experimental group showed significantly greater improvement in grip force after the intervention and at follow-up (P = .049). After adjusting for the baseline measures, the experimental group had an increase in the TMS motor map area compared with the control group over a 4-month period; this increase was of borderline significance (P = .053)., Conclusions: Among subjects who had a stroke within the previous 3 to 9 months, CIMT produced statistically significant and clinically relevant improvements in arm motor function that persisted for at least 4 months. The corresponding enlargement of TMS motor maps, similar to that found in earlier studies of chronic stroke subjects, appears to play an important role in CIMT-dependent plasticity.

Objectives: To measure the efficacy of a program combining mental and physical practice with the efficacy of a program composed of only constraint-induced movement therapy (CIMT) or only mental practice on stroke patients' levels of upper-extremity impairment and upper-extremity functional outcomes and to establish the relationship between changes in blood-oxygen-level dependent (BOLD) functional magnetic resonance imaging response during a specific motor or imagery task and improvement in motor function between intervention groups., Design: Case series., Setting: Licensed, 56-bed, freestanding, university-affiliated rehabilitation hospital., Participants: Three men and 1 woman with moderate upper-limb hemiparesis after stroke were randomized., Interventions: Two patients received mental practice and CIMT, 1 patient received only mental practice, and 1 received only CIMT., Main Outcome Measures: Wolf Motor Function Test (WMFT), Motor Activity Log (MAL), Sirigu break test, Movement Imagery Questionnaire-Revised, and Vividness of Movement Imagery Questionnaire., Results: The mental practice intervention alone led to slight improvement in certain functional and mental imagery measures (Sirigu, MAL, WMFT) but did not result in a clinically meaningful improvement with notable right cerebellar hemisphere activation that was not present before intervention. After CIMT, only the single patient showed clinically meaningful improvement of his affected hand as exhibited by decreased times on the MAL and WMFT. The patient showed increased bilateral cortical activation in both the motor and premotor areas during execution of a finger flexion and extension task. In contrast, during a second task, which was an imagined flexion and extension task, motor, occipital, and inferior parietal activation mainly in the contralateral hemisphere were observed. After 2 weeks of CIMT plus mental practice a patient with a lesion restricted to the parietal cortex showed little improvement in upper-extremity function and mental imagery in comparison with the patient with damage to nonparietal areas, who showed clinically meaningful improvement. The pattern of activation after 2 weeks of CIMT plus mental practice in the patient with nonparietal damage led to more focal contralateral activation in primary motor cortex when executing a voluntary flexion and extension task., Conclusions: The case series indicates that for these patients with chronic, moderate upper-extremity impairment after stroke, a 2-week regimen of CIMT or CIMT plus mental practice only (in 1 case) resulted in modest changes occurring as a decrease in impairment, with functional improvement. Mental practice alone did not result in a clinically meaningful improvement in upper-limb impairment. We describe how these interventions may elicit "plastic" changes in the brain. Further investigations to determine the appropriate delivery and dosing of both physical and mental practice, as well as to determine whether mental practice-induced changes positively correlate with distinct patterns of cortical activation, should be undertaken before the efficacy of their use can be ascertained among patients with limitations comparable with these participants.

EMG and kinetic measures have been primary tools in the study of movement and have provided the foundation for much of the work presented in this journal. Recently, novel ways of combining these tools have provided opportunities to examine elements of motor learning and brain plasticity. This presentation reviews the quantification of EMG within the context of transcranial magnetic stimulation. This vehicle permits acquisition of measures that are fundamental to examining prospects for cortical reorganization among patients with stroke and employs a therapeutic approach called "constraint induced therapy" as a model to demonstrate the interpretation of changes in EMG measures among patients with stroke. Moreover, interfacing novel uses of kinetic measurements during functional task performances is highlighted to illustrate how EMG and kinetics can provide further insight into mechanisms related to reacquisition of movement and concomitant changes in plasticity. Clinicians and researchers interested in expanding their use of these measurement tools are encouraged to learn more about application possibilities.

The authors examined serial changes in optical topography in a stroke patient performing a functional task, as well as clinical and physiologic measures while undergoing constraint-induced therapy (CIT). A 73-year-old right hemiparetic patient, who had a subcortical stroke 4 months previously, received 2 weeks of CIT. During the therapy, daily optical topography imaging using near-infrared light was measured serially while the participant performed a functional key-turning task. Clinical outcome measures included the Wolf Motor Function Test (WMFT), Motor Activity Log (MAL), and functional key grip test. Transcranial magnetic stimulation (TMS) and functional magnetic resonance imaging (fMRI) were also used to map cortical areas and hemodynamic brain responses, respectively. Optical topography measurement showed an overall decrease in oxy-hemoglobin concentration in both hemispheres as therapy progressed and the laterality index increased toward the contralateral hemisphere. An increased TMS motor map area was observed in the contralateral cortex following treatment. Posttreatment fMRI showed bilateral primary motor cortex activation, although slightly greater in the contralateral hemisphere, during affected hand movement. Clinical scores revealed marked improvement in functional activities. In one patient who suffered a stroke, 2 weeks of CIT led to improved function and cortical reorganization in the hemisphere contralateral to the affected hand.

Stroke is a leading cause of long-term disability around the world. Many survivors experience upper extremity (UE) impairment with few rehabilitation opportunities, secondary to a lack of voluntary muscle control. We developed a novel rehabilitation paradigm (TDS-HM) that uses a Tongue Drive System (TDS) to control a UE robotic device (Hand Mentor: HM) while engaging with an interactive user interface. In this study, six stroke survivors with moderate to severe UE impairment completed 15 two-hour sessions of TDS-HM training over five weeks. Participants were instructed to move their paretic arm, with synchronized tongue commands to track a target waveform while using visual feedback to make accurate movements. Following TDS-HM training, significant improvements in tracking performance translated into improvements in the UE portion of the Fugl-Meyer Motor Assessment, range of motion, and all subscores for the Stroke Impact Scale. Regression modeling found daily training time to be a significant predictor of decreases in tracking error, indicating the presence of a potential dose-response relationship. The results of this pilot study indicate that the TDS-HM system can elicit significant improvements in moderate to severely impaired stroke survivors. This pilot study gives preliminary insight into the volume of treatment time required to improve outcomes. [ABSTRACT FROM AUTHOR]

Stroke is a leading cause of death and disability in the USA. Up to 60% of patients do not fully recover despite intensive physical therapy treatment. N-Methyl-D-aspartate receptors (NMDA-R) have been shown to play a role in synaptic plasticity when activated. D-Cycloserine promotes NMDA receptor function by binding to receptors with unoccupied glycine sites. These receptors are involved in learning and memory. We hypothesized that D-cycloserine, when combined with robotic-assisted physiotherapy (RAP), would result in greater gains compared with placebo + RAP in stroke survivors. Participants (n=14) were randomized to D-cycloserine plus RAP or placebo plus RAP. Functional, cognitive, and quality-of-life measures were used to assess recovery. There was significant improvement in grip strength of the affected hand within both groups from baseline to 3 weeks (95% confidence interval for mean change, 3.95 ± 2.96 to 4.90 ± 3.56 N for D-cycloserine and 5.72 ± 3.98 to 8.44 ± 4.90 N for control). SIS mood domain showed improvement for both groups (95% confidence interval for mean change, 72.6 ± 16.3 to 82.9 ± 10.9 for D-cycloserine and 82.9 ± 13.5 to 90.3 ± 9.9 for control). This preliminary study does not provide evidence that D-cycloserine can provide greater gains in learning compared with placebo for stroke survivors. [ABSTRACT FROM AUTHOR]