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Objective: This article describes the findings of a study examining the ability of persons with strokes to use home virtual rehabilitation system (HoVRS), a home-based rehabilitation system, and the impact of motivational enhancement techniques on subjects' motivation, adherence, and motor function improvements subsequent to a 3-month training program. Materials and Methods: HoVRS integrates a Leap Motion controller, a passive arm support, and a suite of custom-designed hand rehabilitation simulations. For this study, we developed a library of three simulations, which include activities such as flexing and extending fingers to move a car, flying a plane with wrist movement, and controlling an avatar running in a maze using reaching movements. Two groups of subjects, the enhanced motivation (EM) group and the unenhanced control (UC) group, used the system for 12 weeks in their homes. The EM group trained using three simulations that provided 8–12 levels of difficulty and complexity. Graphics and scoring opportunities increased at each new level. The UC group performed the same simulations, but difficulty was increased utilizing an algorithm that increased difficulty incrementally, making adjustments imperceptible. Results: Adherence to both the EM and UC protocols exceeded adherence to home exercise programs described in the stroke rehabilitation literature. Both groups demonstrated improvements in upper extremity function. Intrinsic motivation levels were better for the EM group and motivation levels were maintained for the 12-week protocol. Conclusion: A 12-week home-based training program using HoVRS was feasible. Motivational enhancement may have a positive impact on motivation, adherence, and motor outcome.

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.

In this chapter, the experiences of four subjects from a larger trial of video game-based hand and arm rehabilitation for stroke survivors are discussed. We will outline the barriers to participation and adherence to home programs for persons with stroke and relate them to the use of previously developed New Jersey Institute of Technology Home Virtual Rehabilitation System (NJIT-HoVRS), developed to address these barriers. Next we discuss describe the experiences of participants. The four subjects represent the highest and lowest levels of adherence in their protocol groups. Interestingly, more commonalities are observed between the two higher adhering and the two lower adhering subjects than there are when comparing subjects across the two protocols utilized in the study. Age, computer literacy and previous experience with computer games did not have a consistent impact on adherence in these subjects. Moreover, all four subjects demonstrated “clinically significant improvements” in motor function, but only one expressed satisfaction with the outcome. This initial examination suggests that maximizing adherence across a broad sample of subjects might not be achieved an intervention that addresses a set of diagnosis- or population-specific barriers to participation.

Background After stroke, sustained hand rehabilitation training is required for continuous improvement and maintenance of distal function. Methods In this paper, we present a system designed and implemented in our lab: the Home based Virtual Rehabilitation System (HoVRS). Fifteen subjects with chronic stroke were recruited to test the feasibility of the system as well as to refine the design and training protocol to prepare for a future efficacy study. HoVRS was placed in subjects’ homes, and subjects were asked to use the system at least 15 min every weekday for 3 months (12 weeks) with limited technical support and remote clinical monitoring. Results All subjects completed the study without any adverse events. Subjects on average spent 13.5 h using the system. Clinical and kinematic data were collected pre and post study in the subject’s home. Subjects demonstrated a mean increase of 5.2 (SEM = 0.69) on the Upper Extremity Fugl-Meyer Assessment (UEFMA). They also demonstrated improvements in six measurements of hand kinematics. In addition, a combination of these kinematic measures was able to predict a substantial portion of the variability in the subjects’ UEFMA score. Conclusion Persons with chronic stroke were able to use the system safely and productively with minimal supervision resulting in measurable improvements in upper extremity function.

Explore the potential benefits of using priming methods prior to an active hand task in the acute phase post-stroke in persons with severe upper extremity hemiparesis.Five individuals were trained using priming techniques including virtual reality (VR) based visual mirror feedback and contralaterally controlled passive movement strategies prior to training with an active pinch force modulation task. Clinical, kinetic, and neurophysiological measurements were taken pre and post the training period. Clinical measures were taken at six months post training.The two priming simulations and active training were well tolerated early after stroke. Priming effects were suggested by increased maximal pinch force immediately after visual and movement based priming. Despite having no clinically observable movement distally, the subjects were able to volitionally coordinate isometric force and muscle activity (EMG) in a pinch tracing task. The Root Mean Square Error (RMSE) of force during the pinch trace task gradually decreased over the training period suggesting learning may have occurred. Changes in motor cortical neurophysiology were seen in the unaffected hemisphere using Transcranial Magnetic Stimulation (TMS) mapping. Significant improvements in motor recovery as measured by the Action Research Arm Test (ARAT) and the Upper Extremity Fugl Meyer Assessment (UEFMA) were demonstrated at six months post training by three of the five subjects.This study suggests that an early hand-based intervention using visual and movement based priming activities and a scaled motor task allows participation by persons without the motor control required for traditionally presented rehabilitation and testing. Implications for Rehabilitation Rehabilitation of individuals with severely paretic upper extremities after stroke is challenging due to limited movement capacity and few options for therapeutic training. Long-term functional recovery of the arm after stroke depends on early return of active hand control, establishing a need for acute training methods focused distally. This study demonstrates the feasibility of an early hand-based intervention using virtual reality based priming and scaled motor activities which can allow for participation by persons without the motor control required for traditionally presented rehabilitation and testing.

Transcranial magnetic stimulation (TMS) induced motor evoked potentials (MEPs) are an established proxy of corticospinal excitability. As a binary measure, the presence (MEP+) or absence (MEP-) of ipsilesional hemisphere MEPs early following stroke is a robust indicator of long-term recovery, however this measure does not provide information about spatial cortical reorganization. MEPs have been systematically acquired over the sensorimotor cortex to “map” motor topography. In this investigation we compared the degree to which functional improvements resulting from early (

Introduction: Several large trials of task based rehabilitation examining interventions designed to meet the main tenets of experience-dependent neuroplasticity have failed to identify an approach to rehabilitation that produces improvements in hand function that consistently returns persons with stroke to their pre-stroke levels of activity and participation. Several scholars have identified the heightened levels of neuroplasticity occurring immediately after a stroke as an important opportunity to present rehabilitation interventions that will optimize the functional recovery. The study described in this paper begins to examine whether the heightened plasticity occurring early after stroke, when combined with intense technology based upper extremity training, will have a more positive impact than the spontaneous recovery process on its own, or similar interventions presented later, on the long-term recovery of hand and arm function. We hypothesized that early training would allow subjects to integrate their recovering motor abilities into higher levels of activity level performance and that this early integration would result in higher levles of activity level function normalized for impairment level at retention.

Current service delivery models limit treatment time and length of hospital stay during the period of post-ischemic heightened neuronal plasticity when intensive training may optimally affect recovery. Prioritization for rehabilitation of independence in transfers and ambulation, negatively impacts the provision of intensive hand and upper extremity therapy. Our pilot data show that we are able to integrate intensive, targeted hand therapy that uses robotics and a library of gaming activities into the routine of an acute rehabilitation setting. Our system has been specifically designed to deliver hand training when motion and strength are limited. The system uses adaptive algorithms to drive individual finger movement, gain adaptation and workspace modification, and haptic and visual feedback from mirrored movements. The data establishes a foundation for a future clinical trial to investigate the potential benefits of robot-assisted gaming during the early phase of recovery.

The complexity of upper extremity (UE) behavior requires recovery of near normal neuromuscular function to minimize residual disability following a stroke. This requirement places a premium on spontaneous recovery and neuroplastic adaptation to rehabilitation by the lesioned hemisphere. Motor skill learning is frequently cited as a requirement for neuroplasticity. Studies examining the links between training, motor learning, neuroplasticity, and improvements in hand motor function are indicated.This case study describes a patient with slow recovering hand and finger movement (Total Upper Extremity Fugl-Meyer examination score = 25/66, Wrist and Hand items = 2/24 on poststroke day 37) following a stroke. The patient received an intensive eight-session intervention utilizing simulated activities that focused on the recovery of finger extension, finger individuation, and pinch-grasp force modulation.Over the eight sessions, the patient demonstrated improvements on untrained transfer tasks, which suggest that motor learning had occurred, as well a dramatic increase in hand function and corresponding expansion of the cortical motor map area representing several key muscles of the paretic hand. Recovery of hand function and motor map expansion continued after discharge through the three-month retention testing.This case study describes a neuroplasticity based intervention for UE hemiparesis and a model for examining the relationship between training, motor skill acquisition, neuroplasticity, and motor function changes. Implications for rehabilitation Intensive hand and finger rehabilitation activities can be added to an in-patient rehabilitation program for persons with subacute stroke. Targeted training of the thumb may have an impact on activity level function in persons with upper extremity hemiparesis. Untrained transfer tasks can be utilized to confirm that training tasks have elicited motor learning. Changes in cortical motor maps can be used to document changes in brain function which can be used to evaluate changes in motor behavior persons with subacute stroke.

To investigate the ability of the New Jersey Institute of Technology Robot Assisted Virtual Rehabilitation (NJIT-RAVR) system training to elicit changes in upper extremity (UE) function in children with hemiplegia secondary to cerebral palsy.Nine children (mean age 9 years, three males) participated in three pilots. Subjects trained 1 hour, 3 days a week for 3 weeks. Two groups performed this protocol as their only intervention. The third group also performed 5-6 hours of constraint-induced movement therapy.All subjects participated in a short programme of nine, 60-minute training sessions without adverse effects. As a group, subjects demonstrated statistically significant improvements in Melbourne Assessment of Unilateral Upper Limb Function Test, a composite of three timed UE tasks and several measurements of reaching kinematics. Several subjects demonstrated clinically significant improvements in active shoulder abduction and flexion as well as forearm supination.Three small pilots of NJIT-RAVR training demonstrated measurable benefit with no complications, warranting further examination.

Current neuroscience has identified several constructs to increase the effectiveness of upper extremity rehabilitation. One is the use of progressive, skill acquisition-oriented training. Another approach emphasizes the use of bilateral activities. Building on these principles, this paper describes the design and feasibility testing of a robotic / virtual environment system designed to train the arm of persons who have had strokes. The system provides a variety of assistance modes, scalable workspaces and hand-robot interfaces allowing persons with strokes to train multiple joints in three dimensions. The simulations utilize assistance algorithms that adjust task difficulty both online and offline in relation to subject performance. Several distinctive haptic effects have been incorporated into the simulations. An adaptive master-slave relationship between the unimpaired and impaired arm encourages active movement of the subject's hemiparetic arm during a bimanual task. Adaptive anti-gravity support and damping stabilize the arm during virtual reaching and placement tasks. An adaptive virtual spring provides assistance to complete the movement if the subject is unable to complete the task in time. Finally, haptically rendered virtual objects help to shape the movement trajectory during a virtual placement task. A proof of concept study demonstrated this system to be safe, feasible and worthy of further study.

Rehabilitation of individuals with flaccid or severely affected upper extremities is challenging due to their limited motor ability and few options for therapeutic training. This initial study tested the feasibility of training individuals with severe hemiparesis using virtual reality (VR) based mirrored feedback and pinch force modulation tasks. The results demonstrated that the simulations were well tolerated early after stroke. Priming effects of the mirror tasks were suggested by increased maximal pinch force immediately after training. Furthermore, despite having no clinically observable movement distally, the subjects were able to consciously activate their muscles as shown by force traces and EMG recorded during the pinch trace task. Motor learning was also suggested by the decrease in Root Mean Square Error (RMSE) during this task. Lastly the benefits of using objective, technology based measurement tools was demonstrated by the ability of the force sensor to detect small changes in force production that could not be measured with a clinical scale of impairment.

The need to quickly discharge patients following stroke from acute rehabilitation facilities to the home has resulted in an intense focus on restoring safe and independent, if not normal, motor function. Rehabilitation of hand function in patients with upper limb impairment is often de-prioritized to allow for an emphasis on practicing activities necessary for a safe discharge to the home, such as walking and bed mobility. This case study describes a patient with slow recovering hand motor function (hand sub-section of Fugl-Meyer examination score = 2 on post-stroke day 37) following a stroke. The patient received an intensive eight-session intervention that focused on the recovery of finger extension, finger individuation and pinch-grasp force modulation as well as the recovery of proximal upper extremity movement. Over the eight sessions, the patient demonstrated a dramatic increase in hand function and a corresponding expansion of the cortical motor map area representing several key muscles of the paretic hand. Recovery of hand function and motor map expansion continued after discharge through the three-month retention testing. Gains in motor control transferred to clinically meaningful hand function measured at the activity level.

A majority of studies examining repetitive task practice facilitated by robots for the treatment of upper extremity paresis utilize standardized protocols applied to large groups. This study will describe a virtually simulated, robot-based intervention customized to match the goals and clinical presentation of a gentleman with upper extremity hemiparesis secondary to stroke. MP, the subject of this case, is an 85-year-old man with left hemiparesis secondary to an intracerebral hemorrhage 5 years prior to examination. Outcomes were measured before and after a 1-month period of home therapy and after a 1-month virtually simulated, robotic intervention. The intervention was designed to address specific impairments identified during his PT examination. When necessary, activities were modified based on MP's response to his first week of treatment. MP's home training program produced a 3-s decline in Wolf Motor Function Test (WMFT) time and a 5-s improvement in Jebsen Test of Hand Function (JTHF) time. He demonstrated an additional 35-s improvement in JTHF and an additional 44-s improvement in WMFT subsequent to the robotic training intervention. A 24-h activity measurement and the Hand and Activities of Daily Living scales of the Stroke Impact Scale improved following the robotic intervention. Based on his responses to training we feel that we have established that a customized program of virtually simulated, robotically facilitated rehabilitation was feasible and resulted in larger improvements than an intensive home training program in several measurements of upper extremity function in our patient with chronic hemiparesis.

Timed measures of standardized functional tasks are commonly used to measure treatment effects in persons with upper extremity (UE) paresis due to stroke. The effectiveness of their ability to measure motor recovery has come into question because of their inability to distinguish between motor recovery and compensations. This paper presents three linear regression models generated from twelve kinematic measures collected during the performance of a two phase reach/grasp and transport /release activity as performed by 21 persons with upper extremity hemiparesis due to chronic stroke. One of these models demonstrated a statistically significant correlation with the subjects' scores on the Wolf Motor Function Test (WMFT), a battery of fifteen standardized upper extremity functional activities. The second and third models demonstrated a statistically significant correlation with the subjects' WMFT change scores elicited by a two week intensive upper extremity motor rehabilitation intervention. The high correlation suggests that models of kinematic measurements can be used to predict neurologic improvement and the effectiveness of treatment.

This study attempts to identify a difference between a virtually simulated program of repetitive task practice and a similar program of traditionally presented activities. 30 subjects with chronic stroke performed one of the two programs for eight three hour sessions which were performed in a two week period. Both groups demonstrated statistically significant improvements in Upper Extemity Fugyl-Meyer Assessment (UEFMA), Wolf Motor Test and Jebsen-Taylor Tests of Hand Function. Gains in UEFMA were maintained at follow-up. WMFT and JTHF retention scores exceeded baseline at a less than significant level. When comparing the two groups, there were no statistically significant differences at any of the three measurement times and no significant group time interactions. Notable differences in therapist supervision and space requirements suggest that VR based interventions may be able to produce comparable outcomes in a more efficient manner. Continued decreases in the cost of technology may leverage these efficiencies to the point that VR based interventions may become a more cost effective alternative than real-world based therapy.

A majority of studies examining repetitive task practice facilitated by robots for the treatment of upper extremity paresis utilize standardized protocols applied to large groups. Others utilize interventions tailored to patients but do not describe the clinical decision-making process utilized to develop and modify interventions. This case study describes a robot-based intervention customized to match the goals and clinical presentation of person with upper extremity hemiparesis secondary to stroke.The patient, P.M., was an 85-year-old man with left hemiparesis secondary to an intracerebral hemorrhage 5 years prior to examination. Outcomes were measured before and after a 1-month period of home therapy and after a 1-month robotic intervention. The intervention was designed to address specific impairments identified during his physical therapy examination. When necessary, activities were modified on the basis of response to the first week of treatment.P.M. trained in 12 sessions, using six virtually simulated activities. Modifications to original configurations of these activities resulted in performance improvements in five of these activities. P.M. demonstrated a 35-second improvement in Jebsen Test of Hand Function time and a 44-second improvement in Wolf Motor Function Test time subsequent to the robotic training intervention. Reaching kinematics, 24-hour activity measurement, and scores on the Hand and Activities of Daily Living scales of the Stroke Impact Scale all improved as well.A customized program of robotically facilitated rehabilitation was associated with short-term improvements in several measurements of upper extremity function in a patient with chronic hemiparesis.

Objective: This study describes the design and testing of a system designed to quantify improvement in reaching and grasping abilities of the hemiparetic arm and hand of patients post stroke after a series of interactive virtual reality (VR) simulated training sessions. Methods: Five subjects post stroke participated in a two-week training session consisting of interactive computer games for 2–2.5 hours per session. Subjects' finger joint angles were measured during a kinematic reach to grasp test using CyberGlove™ and arm joint angles were measured using the trackSTAR™ system prior to training and after training. Downward force applied to the object during grasping was measured using a force sensor system. Results: There was a significant decrease in force applied to objects when grasping post VR training and an improvement in preshaping the hand during the transport phase. Conclusion: A system utilizing magnetic trackers, a data glove, and a force sensor may be sensitive to changes in motor performance elicited by a robotically facilitated, virtually simulated motor intervention.

This study investigates patterns of brain reorganization in chronic stroke subjects after two weeks of robot-assisted arm and hand training in virtual reality (VR). Four subjects were studied with event-related fMRI while doing simple paretic hand finger movements before (double baseline) and after training. Bilateral hand movements were recorded and used to provide real-time feedback to subjects during scanning to eliminate performance confounds on fMRI results. The kinematic parameters of each movement were also used in the general linear model with the BOLD signal to investigate training-induced changes in neuromotor coupling. Univariate analysis showed an increase in BOLD signal in the ipsilesional hemisphere in two subjects and a decrease in activity in the other two subjects. Seed voxel based functional connectivity analysis revealed an increase in connectivity between ipsilesional motor cortex and bilateral sensorimotor cortex during finger movements in all four subjects. Hemispheric laterality index values showed a tendency to decrease reflecting a reduction in the over-dominance of the contralesional hemisphere. The study is novel in terms of 1) tracking finger movement during a motor task in the scanner, 2) monitoring motor performance during the experiment and 3) giving online visual feedback of subjects’ movement. This pilot study introduces a novel approach to study neural plasticity by combining measures of regional intensity, inter-regional interactions (using functional connectivity analysis and hemispheric laterality index), and modulation in the strength of neuromotor coupling.

Nine children with cerebral palsy and nine adults with stroke were trained using 5 different upper extremity simulations using the NJIT-RAVR system for approximately nine to twelve hours over a three week period. Both groups made improvements in clinical measurements of upper extremity function and reaching kinematics. Patterns and magnitudes of improvement differ between the two groups. Responses to training required adjustment of the robotic system to accommodate the rehabilitation needs of children with cerebral palsy.

This study describes the design and feasibility testing of a hand rehabilitation system that provides haptic assistance for hand opening in moderate to severe hemiplegia while subjects attempt to perform bilateral hand movements. A cable-actuated exoskeleton robot assists the subjects in performing impaired finger movements but is controlled by movement of the unimpaired hand. In an attempt to combine the neurophysiological stimuli of bilateral movement and action observation during training, visual feedback of the impaired hand is replaced by feedback of the unimpaired hand, either by using a sagittaly oriented mirror or a virtual reality setup with a pair of virtual hands presented on a flat screen controlled with movement of the unimpaired hand, providing a visual image of their paretic hand moving normally. Joint angles for both hands are measured using data gloves. The system is programmed to maintain a symmetrical relationship between the two hands as they respond to commands to open and close simultaneously. Three persons with moderate to severe hemiplegia secondary to stroke trained with the system for eight, 30 to 60 minute sessions without adverse events. Each demonstrated positive motor adaptations to training. The system was well tolerated by persons with moderate to severe upper extremity hemiplegia. Further testing of its effects on motor ability with a broader range of clinical presentations is indicated.

This paper describes the preliminary results of an ongoing study of the effects of two training approaches on motor function and learning in persons with hemi paresis due to cerebrovascular accidents. Eighteen subjects with chronic stroke performed eight, three-hour sessions of sensorimotor training in haptically renedered environments. Eleven subjects performed training activities that integrated hand and arm movement while another seven subjects performed activities that trained the hand and arm with separately. As a whole, the eighteen subjects made statistically significant improvements in motor function as evidenced by robust improvements in Wolf Motor Function Test times and corresponding improvements in Jebsen Test of Hand Function times. There were no significant between group effects for these tests. However, the two training approaches elicited different patterns and magnitudes of performance improvement that suggest that they may elicit different types of change in motor learning and or control.

This paper will describe the NJIT-RAVR system, which combines adaptive robotics with complex VR simulations for the rehabilitation of upper extremity impairments and function in children with CP. The feasibility of this system is examined in the context of two pilot studies. The NJIT-RAVR system consists of the Haptic Master, a 6 degrees of freedom, admittance controlled robot and a suite of rehabilitation simulations that we have developed. The system provides adaptive algorithms for the Haptic Master, allowing impaired users to interact with rich virtual environments. All subjects trained with the NJIT-RAVR System for one hour, 3 days a week for three weeks. Both groups improved in robotically collected kinematic measures and the Melbourne Assessment of Unilateral Upper Limb Function.

Recent discoveries demonstrate that the brain can be remodeled after stroke, principally through new synaptic generation. Task-specific & repetitive training are critical factors in promoting this synaptic generation & are central components in rehabilitation of upper extremity (UE) motor weakness following stroke. Virtual reality (VR) based therapy have been shown to be effective at facilitating specific & consistently repetitive movements during training. In combination with robotics the nature of the training can be further tailored to fit the patient's rehabilitative needs. This paper describes the design & consideration of The Blood Cell Game, a new VR game used in UE stroke rehabilitation in the New Jersey Institute of Technology robot assisted virtual reality training system (RAVR).

This paper will describe the NJIT-RAVR system, which combines adaptive robotics with complex VR simulations for the rehabilitation of upper extremity impairments and function in children with CP. The feasibility of this system is examined in the context of two pilot studies. The NJIT-RAVR system consists of the Haptic Master, a 6 degrees of freedom, admittance controlled robot and a suite of rehabilitation simulations that we have developed. The system provides adaptive algorithms for the Haptic Master, allowing impaired users to interact with rich virtual environments. All subjects trained with the NJIT-RAVR System for one hour, 3 days a week for three weeks. The subjects played a combination of four or five simulations depending on their therapeutic goals, tolerances and preferences. Subjects differed in the level of activity performed outside of NJIT-RAVR system training. Each group of subjects performed a battery of clinical testing and kinematic measurements of reaching collected by the NJIT-RAVR system. Both groups improved in robotically collected kinematic measures and the Melbourne Assessment of Unilateral Upper Limb Function.

We describe the design and testing of a system that integrates rich virtual environments and assist as needed robotics to allow children with upper extremity impairments to perform rehabilitation activities in the form of computer games. Five simulations as well as positioning and interface approaches are described. To provide proof of concept we trained four children with mild to moderate upper extremity hemiplegia secondary to cerebral palsy. The children made improvements in clinical measures of upper extremity function and reaching kinematics as measured by the robot.

Various authors have described pre and post testing improvements in upper limb coordination as a result of intensive upper limb interventions. While the ability to alter coordination patterns as a result of repetitive hand-arm movement is established, patterns of change in the relationship between proximal and distal effectors of the UE over the course of multiple sessions of training have not been described in the rehabilitation literature. In this study eight subjects (5 male, 3 female) with a mean age of 56.4 years (SD=14.2) and a mean time since CVA of 54.7 months post-stroke (SD=51.7) were trained for eight, 2–3 hour sessions on four robotically facilitated virtual rehabilitation activities. This paper will present 1) Functional performance and pre and post testing kinematic analysis for the eight subjects 2) More extensive analysis of the change in hand and arm coordination over the course of the eight session intervention demonstrated by one of the subjects from this sample 3) Kinematic analysis of another subject from this sample performing an un-trained reaching and grasping activity, before and after training.

This study describes a novel robotic system using haptic effects and objects, in rich, three- dimensional virtual environments (VEs) for the sensorimotor training of the hemiparetic hand. This system is used to compare effectiveness of two training paradigms, one using activities that train the hand and arm together (HAT) as a functional unit to training the hand and arm in similar conditions, separately (HAS). Four subjects practiced three hours/day for 8 days using (HAS) robotic simulations. Four subjects practiced same amount of time using HAT simulations. HAT group improved 23% in the Wolf Motor Function Test and 29% in the Jebsen Test of Hand Function, whereas HAS group only improved 14% and 8%. HAT group also demonstrated larger decreases in hand trajectory length in the VE-based training that involved reaching and object placing, indicating improved limb segment coordination, (40% HAT; 19% HAS). Both groups improved the smoothness of robotically measured hand trajectories 56%, suggesting improved motor control. During virtual piano training, subjects showed similar improvements in key press accuracy (17% HAT; 20% HAS) however, the HAT group demonstrated larger improvements in average time needed to press a key (151% HAT; 60% HAS). Our initial findings suggest that training the arm and hand as a unit following stroke may be more effective for improving upper extremity function than training the hand and arm in isolation.

Existing research suggests that limb motion can be represented as an Equilibrium Point (EP) trajectory in combination with a trajectory that reflects specified damping and stiffness at each joint. This model utilizes the concept of relative damping, an integral factor in defining the Equilibrium Point trajectory, to help maintain stability during the arm movement. By using commercialized Flock of Bird® (FOB) sensor, we can obtain experimental trajectories and angular information for human elbow and shoulder joints, as well as forearm and upper arm position during reaching in slow and fast movements. We replaced the complicated inverse kinematics computation of brain with our simple relative damping model, and then calculated the EP trajectories of the elbow and shoulder to use as inputs to our following forward kinematics model. The model generated trajectories which closely match the experimental data. The novel features of this model include the EP trajectory input generated by relative damping. Therefore, we conclude that multi-joint manipulations can be modeled by an appropriate EP trajectory along with relative damping.Copyright © 2008 by ASME

We have previously designed a virtual reality-based training system for hand rehabilitation. Here we report the design of an extended version of the system that allows training of the hemiparetic arm and hand during one training session, and provides haptic assistance during hand motion and during arm movements in three-dimensional space. It also allows bimanual training of the hand and arm. Hand training was based on a virtual piano activity that was designed to promote finger range of motion and independence. Hand exercises included reaching to stationary and moving targets presented in stereo. The use of a three-dimensional robot based on admittance control allowed the use of active force applied by the subject as an input to the haptic controller. Two stroke survivors were trained for three weeks using computer gamelike activities. Subjects improved on movement kinematics and on several of the clinical tests.

We have previously designed a virtual reality-based training system for hand rehabilitation. Here we report the design of an extended version of the system that allows training of the hemiparetic arm and hand, and provides haptic assistance during hand and arm motions in three-dimensional space. It also allows bimanual training of the hand and arm. Hand training was based on a virtual piano activity that was designed to promote finger range of motion and independence of finger motion. Arm training was based upon unilateral and bilateral reaching to stationary and moving targets. The use of a three-dimensional robot based on admittance control allowed the use of active force applied by the subject as an input to the haptic controller. Two subjects post-stroke were trained for three weeks using computer game-like activities. Subjects improved on movement kinematics, kinetics and on several of the clinical tests.