Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> Outcome Measures <s> This experiment investigates movement coordination in Parkinson's disease (PD) subjects. Seventeen PD patients and 12 elderly control subjects performed several handwriting-like tasks on a digitizing writing tablet resting on top of a table in front of the subject. The writing patterns, in increasing order of coordination complexity, were repetitive back-and-forth movements in various orientations, circles and loops in clockwise and counterclockwise directions, and a complex writing pattern. The patterns were analyzed in terms of jerk normalized for duration and size per stroke. In the PD subjects, back-and-forth strokes, involving coordination of fingers and wrist, showed larger normalized jerk than strokes performed using either the wrist or the fingers alone. In the PD patients, wrist flexion (plus radial deviation) showed greater normalized jerk in comparison to wrist extension (plus ulnar deviation). The elderly control subjects showed no such effects as a function of coordination complexity. For both PD and elderly control subjects, looping patterns consisting of circles with a left-to-right forearm movement, did not show a systematic increase of normalized jerk. The same handwriting patterns were then simulated using a biologically inspired neural network model of the basal ganglia thalamocortical relations for a control and a mild PD subject. The network simulation was consistent with the observed experimental results, providing additional support that a reduced capability to coordinate wrist and finger movements may be caused by suboptimal functioning of the basal ganglia in PD. The results suggest that in PD patients fine motor control problems may be caused by a reduced capability to coordinate the fingers and wrist and by reduced control of wrist flexion. <s> BIB001 </s> Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> Outcome Measures <s> This investigation is one in a series of studies that address the possibility of stroke rehabilitation using robotic devices to facilitate “adaptive training.” Healthy subjects, after training in the presence of systematically applied forces, typically exhibit a predictable “after-effect.” A critical question is whether this adaptive characteristic is preserved following stroke so that it might be exploited for restoring function. Another important question is whether subjects benefit more from training forces that enhance their errors than from forces that reduce their errors. We exposed hemiparetic stroke survivors and healthy age-matched controls to a pattern of disturbing forces that have been found by previous studies to induce a dramatic adaptation in healthy individuals. Eighteen stroke survivors made 834 movements in the presence of a robot-generated force field that pushed their hands proportional to its speed and perpendicular to its direction of motion — either clockwise or counterclockwise. We found that subjects could adapt, as evidenced by significant after-effects. After-effects were not correlated with the clinical scores that we used for measuring motor impairment. Further examination revealed that significant improvements occurred only when the training forces magnified the original errors, and not when the training forces reduced the errors or were zero. Within this constrained experimental task we found that error-enhancing therapy (as opposed to guiding the limb closer to the correct path) to be more effective than therapy that assisted the subject. <s> BIB002 </s> Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> Outcome Measures <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> BIB003 </s> Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> Outcome Measures <s> BackgroundIt is common for individuals with chronic disabilities to continue using the compensatory movement coordination due to entrenched habits, increased perception of task difficulty, or personality variables such as low self-efficacy or a fear of failure. Following our previous work using feedback distortion in a virtual rehabilitation environment to increase strength and range of motion, we address the use of visual feedback distortion environment to alter movement coordination patterns.MethodsFifty-one able-bodied subjects participated in the study. During the experiment, each subject learned to move their index finger and thumb in a particular target pattern while receiving visual feedback. Visual distortion was implemented as a magnification of the error between the thumb and/or index finger position and the desired position. The error reduction profile and the effect of distortion were analyzed by comparing the mean total absolute error and a normalized error that measured performance improvement for each subject as a proportion of the baseline error.ResultsThe results of the study showed that (1) different coordination pattern could be trained with visual feedback and have the new pattern transferred to trials without visual feedback, (2) distorting individual finger at a time allowed different error reduction profile from the controls, and (3) overall learning was not sped up by distorting individual fingers.ConclusionIt is important that robotic rehabilitation incorporates multi-limb or finger coordination tasks that are important for activities of daily life in the near future. This study marks the first investigation on multi-finger coordination tasks under visual feedback manipulation. <s> BIB004 </s> Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> Outcome Measures <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> BIB005 </s> Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> Outcome Measures <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> BIB006 </s> Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> Outcome Measures <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> BIB007 </s> Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> Outcome Measures <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> BIB008 </s> Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> Outcome Measures <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> BIB009 </s> Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> Outcome Measures <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> BIB010 </s> Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> Outcome Measures <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> BIB011 </s> Error Augmented Robotic Rehabilitation of the Upper Limb - A Review <s> Outcome Measures <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> BIB012
The most common clinical measures among the studies that were used to evaluate outcome on stroke patients were the Fugl-Meyer scale, the Modified Ashworth scale for spasticity and the Box and Block test. Other clinical measures used can be found in Table 3 . In the above-mentioned studies kinematic data were collected namely, error that is to say the deviation between the actual and desired trajectory, jerk index (Squeri et al., 2007a) , Jerk (Teulings') index BIB001 , and strength BIB003 BIB002 BIB005 BIB006 BIB009 BIB010 . Both studies that performed trials in patients with multiple sclerosis (Squeri et al., 2007a; BIB007 evaluated performance with clinical measures such as Expanded Disability Status Scale (EDSS), Ataxia and Tremor scale, Nine Hole Peg Test, Visual Analogue Scale (VAS) and the Tremor and Activity of Daily Life (TADL) questionnaire as well as kinematic such as, lateral deviation (root mean square value) from the nominal path, movement duration (seconds), symmetry (ration between acceleration and deceleration phases) and smoothness. Likewise, studies that employed only ablebodied participants used only kinematic measures like error (distance between actual and desired directory, lateral deviation etc.), mean lag BIB004 and times needed assistance. The times needed assistance measure was used in one study BIB008 where visual error augmentation was utilized. In this studies training scheme the system would assist movement only when a threshold in error was reached. In one study BIB012 a Self-Assessment Manikin (SAM) affect questionnaire was administered. Finally, in the study where trials on children with primary dystonia were performed BIB011 only clinical measures were used that is to say, Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS). A more detailed overview of the outcome measures used according to condition can be found in Table 3 .