Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> CONCLUSSIONS <s> Summary Rehabilitation after hemiplegic stroke has typically relied on the training of patients in compensatory strategies. The translation of neuroscientific research into care has led to new approaches and renewed promise for better outcomes. Improved motor control can progress with task-specific training incorporating increased use of proximal and distal movements during intensive practice of real-world activities. Functional gains are incorrectly said to plateau by 3–6 months. Many patients retain latent sensorimotor function that can be realised any time after stroke with a pulse of goal-directed therapy. The amount of practice probably best determines gains for a given level of residual movement ability. Clinicians should encourage patients to build greater strength, speed, endurance, and precision of multijoint movements on tasks that increase independence and enrich daily activity. Imaging tools may help clinicians determine the capacity of residual networks to respond to a therapeutic approach and help establish optimal doseresponse curves for training. Promising adjunct approaches include practice with robotic devices or in a virtual environment, electrical stimulation to increase cortical excitability during training, and drugs to optimise molecular mechanisms for learning. Biological strategies for neural repair may augment rehabilitation in the next decade. <s> BIB001 </s> Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> CONCLUSSIONS <s> We present an initial test of a technique for retrain- ing reaching skills in patients with poststroke hemiparesis, in which errors are temporarily magnified to encourage learning and compensation. Individuals with poststroke hemiparesis held a horizontal plane robotic manipulandum that could exert a variety of forces while recording patients' movements. We measured how well the patients recovered movement straight- ness in a single visit to the laboratory (~3 h). Following train- ing, we returned forces to zero for an additional 50 movements to discern if aftereffects lasted. We found that all subjects showed immediate benefit from the training, although 3 of the 10 subjects did not retain these benefits for the remainder of the experiment. We discuss how these approaches demonstrate great potential for rehabilitation tools that augment error to facilitate functional recovery. <s> BIB002 </s> Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> CONCLUSSIONS <s> The present study is aimed at developing new rehabilitation protocols to be used in post-stroke robotic-aided therapy. In the recent past, it has been suggested that the use of robotic training forces that enhance error instead of reducing it, could stimulate new learning and feedback strategies at the base of an effective motor recovery. Starting from these findings, in this work two different robotic-aided therapies were compared: the first was based on the constraint induced movement therapy, the second employed an unstable training force field increasing path errors performed by the subjects. The results shows that the use of the unstable divergent force field can increase the recovery, especially in people with mild level of impairment. <s> BIB003 </s> Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> CONCLUSSIONS <s> Recent research has suggested that enhanced retraining for stroke patients using haptics (robotic forces) and graphics (visual display) to generate a practice environment that can artificially enhance error rather than reducing it, can stimulate new learning and foster accelerated recovery. We present an evaluation of early results of this novel post-stroke robotic-aided therapy trial that incorporates these ideas in a large VR system and simultaneously employs the patient, the therapist, and the technology to accomplish effective therapy. <s> BIB004 </s> Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> CONCLUSSIONS <s> BackgroundCerebellar symptoms are extremely disabling and are common in Multiple Sclerosis (MS) subjects. In this feasibility study, we developed and tested a robot therapy protocol, aimed at the rehabilitation of incoordination in MS subjects.MethodsEight subjects with clinically defined MS performed planar reaching movements while grasping the handle of a robotic manipulandum, which generated forces that either reduced (error-reducing, ER) or enhanced (error-enhancing, EE) the curvature of their movements, assessed at the beginning of each session. The protocol was designed to adapt to the individual subjects' impairments, as well as to improvements between sessions (if any). Each subject went through a total of eight training sessions. To compare the effect of the two variants of the training protocol (ER and EE), we used a cross-over design consisting of two blocks of sessions (four ER and four EE; 2 sessions/week), separated by a 2-weeks rest period. The order of application of ER and EE exercises was randomized across subjects. The primary outcome measure was the modification of the Nine Hole Peg Test (NHPT) score. Other clinical scales and movement kinematics were taken as secondary outcomes.ResultsMost subjects revealed a preserved ability to adapt to the robot-generated forces. No significant differences were observed in EE and ER training. However over sessions, subjects exhibited an average 24% decrease in their NHPT score. The other clinical scales showed small improvements for at least some of the subjects. After training, movements became smoother, and their curvature decreased significantly over sessions.ConclusionsThe results point to an improved coordination over sessions and suggest a potential benefit of a short-term, customized, and adaptive robot therapy for MS subjects. <s> BIB005 </s> Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> CONCLUSSIONS <s> The paper investigates the impact of the integration of the visual error augmentation training method with the assist-as-needed training method in robot-assisted rehabilitation training of the upper extremity. A robot-assisted rehabilitation system is developed that integrates an assistive controller, which can provide robotic assistance to the participant as and when needed, with a visual error augmentation mechanism, which amplifies the tracking error to heighten the participant's motivation to improve tracking accuracy. A crossover study is designed to evaluate the impact of the integration of the visual error augmentation method with the assist-as-needed training method. Experimental results on unimpaired participants demonstrate improved performance has been achieved in the integrated training session. <s> BIB006 </s> Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> CONCLUSSIONS <s> Here we present results where nineteen stroke survivors with chronic hemiparesis simultaneously employed the trio of patient, therapist, and machine. Massed practice combined with error augmentation, where haptic (robotic forces) and graphic (visual display) distortions are used to enhance the feedback of error, was compared to massed practice alone. The 6-week randomized crossover design involved approximately 60 minutes of daily treatment three times per week for two weeks, followed by one week of rest, and then repeated using the alternate treatment protocol. A therapist provided a visual target using a tracking device that moved a cursor in front of the patient, who was instructed to maintain the cursor on the target. The patient, therapist, technician-operator, and rater were blinded to treatment type. Several clinical measures gauged outcomes at the beginning and end of each 2-week period and one week post training. Results showed incremental benefit across most but not all days, abrupt gains in performance, and a benefit to error augmentation training in final evaluations. This application of interactive technology may be a compelling new method for enhancing a therapist's productivity in stroke-rehabilitation. <s> BIB007 </s> Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> CONCLUSSIONS <s> Feedback is an important element in motor learning during rehabilitation therapy following stroke. The objective of this pilot study was to better understand the effect of position feedback during task-oriented reach training of the upper limb in people with chronic stroke. Five subjects participated in the training for 30 minutes three times a week for 6 weeks. During training, subjects performed reaching movements over a predefined path. When deviation from this path occurred, shoulder and elbow joints received position feedback using restraining forces. We recorded the amount of position feedback used by each subject. During pre- and posttraining assessments, we collected data from clinical scales, isometric strength, and workspace of the arm. All subjects showed improvement on one or several kinematic variables during a circular motion task after training. One subject showed improvement on all clinical scales. Subjects required position feedback between 7.4% and 14.7% of training time. Although augmented feedback use was limited, kinematic outcome measures and movement performance during training increased in all subjects, which was comparable with other studies. Emphasis on movement errors at the moment they occur may possibly stimulate motor learning when movement tasks with sufficiently high levels of difficulty are applied. <s> BIB008 </s> Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> CONCLUSSIONS <s> Background ::: Robot-generated deviating forces during multijoint reaching movements have been applied to investigate motor control and to tune neuromotor adaptation. Can the application of force to limbs improve motor learning? In this framework, the response to altered dynamic environments of children affected by primary dystonia has never been studied. <s> BIB009 </s> Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> CONCLUSSIONS <s> To study the effects of different feedback error amplification methods on a subject's upper-limb motor learning and affect during a point-to-point reaching exercise, we developed a real-time controller for a robotic manipulandum. The reaching environment was visually distorted by implementing a thirty degrees rotation between the coordinate systems of the robot's end-effector and the visual display. Feedback error amplification was provided to subjects as they trained to learn reaching within the visually rotated environment. Error amplification was provided either visually or through both haptic and visual means, each method with two different amplification gains. Subjects' performance (i.e., trajectory error) and self-reports to a questionnaire were used to study the speed and amount of adaptation promoted by each error amplification method and subjects' emotional changes. We found that providing haptic and visual feedback promotes faster adaptation to the distortion and increases subjects' satisfaction with the task, leading to a higher level of attentiveness during the exercise. This finding can be used to design a novel exercise regimen, where alternating between error amplification methods is used to both increase a subject's motor learning and maintain a minimum level of motivational engagement in the exercise. In future experiments, we will test whether such exercise methods will lead to a faster learning time and greater motivation to pursue a therapy exercise regimen. <s> BIB010
Error augmentation in upper limb robotic rehabilitation is a relatively new area of study, counting almost nine years since the first relevant publication, and a rather understudied one. Despite the small number of publications that have employed this modality, there are some clear indications about its potential benefits. The evidence gathered from this review indicate that stroke patients received the most benefit from haptic error augmented therapy but no clear conclusions were drawn whether this training modality has significant benefits on stroke patients, over other established modalities such as error reducing or assistive therapy. We suggest that large scale randomized control trials be undertaken in order to explore the prospects of haptic error augmentation and fully evaluate its effectiveness on upper limb robotic rehabilitation. In these trials error augmented therapy should be compared against other, more established training schemes. Furthermore, we suggest that the impact of error augmented therapy should be explored in conditions that share similar symptoms related to neuromuscular control to stroke, such as cerebral palsy. Understanding the neurological mechanisms targeted by different therapies, in terms of both learning and motor performance, could provide greater insight into their potential efficacy in a range of different pathologies and is an important consideration for future studies. Likewise, we would like to encourage scientists to perform trials on impaired subjects where error augmentation on visual feedback will be implemented as the results of this review indicate that this modality hasn't been researched to its full capacity. Guidelines on trial design and dose administration for rehabilitation of the upper limb in conditions such as stroke have been presented in literature BIB001 . To the author's knowledge, reviews on the outcome measures for robotic rehabilitation of the upper limb in conditions such as cerebral palsy, primary dystonia and multiple sclerosis have not yet been conducted, while one review regarding such measures has been undertaken for the rehabilitation for the upper limb in stroke patients  . This review has identified that there is no uniform condition-specific trial design or evaluation protocol as different intervention protocols and different measures have been used in trials with participants of the same condition. As a result of this a comparison between trials and their outcomes is difficult. Adoption of standard outcome measures would enable inter-study evaluation and help to progress this area of research significantly. As robotic rehabilitation of the upper limb is getting more and more accepted by the scientific community as a valid rehabilitation modality, we believe that uniform condition-specific trial protocol guidelines should be established, in order to enable researchers to easily evaluate the outcome of relevant studies in literature and allow them to compare the outcome of their studies against that of others. approx. 49.00 min 45 movements at the end of the session 2 weeks after 4 sessions before protocol change BIB003 20 60.00 min n/a n/a 60.00 min 2 weeks after 10 sessions before protocol change BIB004 6 40.00 min n/a n/a 35.00 min 2 weeks after 6 sessions before protocol change BIB005 8 60.00 min 498 a) Robot training = 120 b) Subject training = 288 approx. 37.00 min 2 weeks after 4 sessions before protocol change BIB006 2 n/a 25 Total = 25 n/a n/a BIB007 12 60.00 min n/a n/a 30.00 min 2 weeks after 6 sessions before protocol change BIB008 18 30.00 min n/a n/a 30.00 min n/a BIB009 1 n/a 55 a) Null additive force = 15 b) Disturbing force =15 c) Deactivation of additive external force = 15 Total = 45 n/a n/a BIB010 BIB002 error enhancing stroke