Posts Tagged motor skills
[WEB SITE] Virtual reality intervention shows promise to repair mobility and motor skills in impaired limb
A combination of traditional physical therapy and technology may improve the motor skills and mobility of an impaired hand by having its partner, more mobile hand lead by example through virtual reality training, new Tel Aviv University research suggests.
“Patients suffering from hemiparesis — the weakness or paralysis of one of two paired limbs — undergo physical therapy, but this therapy is challenging, exhausting, and usually has a fairly limited effect,” said lead investigator Prof. Roy Mukamel of TAU’s School of Psychological Sciences and Sagol School of Neuroscience, who conducted the research with his student Ori Ossmy. “Our results suggest that training with a healthy hand through a virtual reality intervention provides a promising way to repair mobility and motor skills in an impaired limb.” The research was published in Cell Reports.
Does the left hand know what the right hand is doing?
53 healthy participants completed baseline tests to assess the motor skills of their hands, then strapped on virtual reality headsets that showed simulated versions of their hands. The virtual reality technology, however, presented the participants with a “mirror image” of their hands — when they moved their real right hand, their virtual left hand would move.
In the first experiment, participants completed a series of finger movements with their right hands, while the screen showed their “virtual” left hands moving instead. In the next, participants placed motorized gloves on their left hands, which moved their fingers to match the motions of their right hands. Again, the headsets presented the virtual left hands moving instead of their right hands.
The research team found that when subjects practiced finger movements with their right hands while watching their left hands on 3D virtual reality headsets, they could use their left hands more efficiently after the exercise. But the most notable improvements occurred when the virtual reality screen showed the left hand moving while in reality the motorized glove moved the hand.
Tricking the brain
“We effectively tricked the brain,” said Prof. Mukamel.
“Technologically, these experiments were a big challenge,” Prof. Mukamel continued. “We manipulated what people saw and combined it with the passive, mechanical movement of the hand to show that our left hand can learn even when it is not moving under voluntary control.”
The researchers are optimistic that this research could be applied to patients in physical therapy programs who have lost the strength or control of one hand. “We need to show a way to obtain high-performance gains relative to other, more traditional types of therapies,” said Prof. Mukamel. “If we can train one hand without voluntarily moving it and still show significant improvements in the motor skills of that hand, we’ve achieved the ideal.”
The researchers are currently examining the applicability of their novel VR training scheme to stroke patients.
[ARTICLE] A Rehabilitation-Internet-of-Things in the Home to Augment Motor Skills and Exercise Training – Full Text
Although motor learning theory has led to evidence-based practices, few trials have revealed the superiority of one theory-based therapy over another after stroke. Nor have improvements in skills been as clinically robust as one might hope. We review some possible explanations, then potential technology-enabled solutions.
Over the Internet, the type, quantity, and quality of practice and exercise in the home and community can be monitored remotely and feedback provided to optimize training frequency, intensity, and progression at home. A theory-driven foundation of synergistic interventions for walking, reaching and grasping, strengthening, and fitness could be provided by a bundle of home-based Rehabilitation Internet-of-Things (RIoT) devices.
A RIoT might include wearable, activity-recognition sensors and instrumented rehabilitation devices with radio transmission to a smartphone or tablet to continuously measure repetitions, speed, accuracy, forces, and temporal spatial features of movement. Using telerehabilitation resources, a therapist would interpret the data and provide behavioral training for self-management via goal setting and instruction to increase compliance and long-term carryover.
On top of this user-friendly, safe, and conceptually sound foundation to support more opportunity for practice, experimental interventions could be tested or additions and replacements made, perhaps drawing from virtual reality and gaming programs or robots. RIoT devices continuously measure the actual amount of quality practice; improvements and plateaus over time in strength, fitness, and skills; and activity and participation in home and community settings. Investigators may gain more control over some of the confounders of their trials and patients will have access to inexpensive therapies.
Neurologic rehabilitation has been testing a motor learning theory for the past quarter century that may be wearing thin in terms of leading to more robust evidence-based practices. The theory has become a mantra for the field that goes like this. Repetitive practice of increasingly challenging task-related activities assisted by a therapist in an adequate dose will lead to gains in motor skills, mostly restricted to what was trained, via mechanisms of activity-dependent induction of molecular, cellular, synaptic, and structural plasticity within spared neural ensembles and networks.
This theory has led to a range of evidence-based therapies, as well as to caricatures of the mantra (eg, a therapist says to patient, “Do those plasticity reps!”). A mantra can become too automatic, no longer apt to be reexamined as a testable theory. A recent Cochrane review of upper extremity stroke rehabilitation found “adequately powered, high-quality randomized clinical trials (RCTs) that confirmed the benefit of constraint-induced therapy paradigms, mental practice, mirror therapy, virtual reality paradigms, and a high dose of repetitive task practice.”1 The review also found positive RCT evidence for other practice protocols. However, they concluded, no one strategy was clearly better than another to improve functional use of the arm and hand. The ICARE trial2 for the upper extremity after stroke found that both a state-of-the-art Accelerated Skill Acquisition Program (motor learning plus motivational and psychological support strategy) compared to motor learning-based occupational therapy for 30 hours over 10 weeks led to a 70% increase in speed on the Wolf Motor Function Test, but so did usual care that averaged only 11 hours of formal but uncharacterized therapy. In this well-designed RCT, the investigators found no apparent effect of either the dose or content of therapy. Did dose and content really differ enough to reveal more than equivalence, or is the motor-learning mantra in need of repair?
Walking trials after stroke and spinal cord injury,3–8 such as robot-assisted stepping and body weight-supported treadmill training (BWSTT), were conceived as adhering to the task-oriented practice mantra. But they too have not improved outcomes more than conventional over-ground physical therapy. Indeed, the absolute gains in primary outcomes for moderate to severely impaired hemiplegic participants after BWSTT and other therapies have been in the range of only 0.12 to 0.22 m/s for fastest walking speed and 50 to 75 m for 6-minute walking distance after 12 to 36 training sessions over 4 to 12 weeks.3,9 These 15% to 25% increases are just as disappointing when comparing gains in those who start out at a speed of <0.4 m/s compared to >0.4 to 0.8 m/s.3
Has mantra-oriented training reached an unanticipated plateau due to inherent limitations? Clearly, if not enough residual sensorimotor neural substrate is available for training-induced adaptation or for behavioral compensation, more training may only fail. Perhaps, however, investigators need to reconsider the theoretical basis for the mantra, that is, whether they have been offering all of the necessary components of task-related practice, such as enough progressively difficult practice goals, the best context and environment for training, the behavioral training that motivates compliance and carryover of practice beyond the sessions of formal training, and blending in other physical activities such as strengthening and fitness exercise that also augment practice-related neural plasticity? These questions point to new directions for research….
Components of a Rehabilitation-Internet-of-Things: wireless chargers for sensors (1), ankle accelerometers with gyroscopes (2) and Android phone (3) to monitor walking and cycling, and a force sensor (4) in line with a stretch band (5) to monitor resistance exercises.
[Abstract] Cognitive motor interference on upper extremity motor performance in a robot-assisted planar reaching task among patients with stroke
To explore motor performance on two different cognitive tasks during robotic rehabilitation in which motor performance was longitudinally assessed.
Patients with chronic stroke and upper extremity impairment (N=22)
A total of 640 repetitions of robot-assisted planar reaching, five times a week for 4 weeks
Main Outcome Measures
Longitudinal robotic evaluations regarding motor performance included smoothness, mean velocity, path error, and reach error by the type of cognitive task. Dual-task effects (DTE) of motor performance were computed in order to analyze the effect of the cognitive task on dual-task interference.
Cognitive task type influenced smoothness (p = 0.006), the DTE of smoothness (p = 0.002), and the DTE of reach error (p = 0.052). Robotic rehabilitation improved smoothness (p = 0.007) and reach error (p = 0.078), while stroke severity affected smoothness (p = 0.01), reach error (p < 0.001), and path error (p = 0.01). Robotic rehabilitation or severity did not affect the DTE of motor performance.
The present results provide evidence for the effect of cognitive-motor interference on upper extremity performance among participants with stroke using a robotic-guided rehabilitation system.
Cognitive-motor interference (CMI), Fugl-Meyer assessment (FMA), dual-task effects (DTE), dual-task loss (DTL), Digit span test (DST), Controlled Oral Word Association Test (COWAT), repeated measures (RM), analysis of variance (ANOVA)
Background and Objective: Stroke rehabilitation assumes motor learning contributes to motor recovery, yet motor learning in stroke has received little systematic investigation. Here we aimed to illustrate that despite matching levels of performance on a task, a trained patient should not be considered equal to an untrained patient with less impairment. Methods: We examined motor learning in healthy control participants and groups of stroke survivors with mild-to-moderate or moderate-to-severe motor impairment. Participants performed a series of isometric contractions of the elbow flexors to navigate an on-screen cursor to different targets, and trained to perform this task over a 4-day period. The speed-accuracy trade-off function (SAF) was assessed for each group, controlling for differences in self-selected movement speeds between individuals. Results: The initial SAF for each group was proportional to their impairment. All groups were able to improve their performance through skill acquisition. Interestingly, training led the moderate-to-severe group to match the untrained (baseline) performance of the mild-to-moderate group, while the trained mild-to-moderate group matched the untrained (baseline) performance of the controls. Critically, this did not make the two groups equivalent; they differed in their capacity to improve beyond this matched performance level. Specifically, the trained groups had reached a plateau, while the untrained groups had not. Conclusions: Despite matching levels of performance on a task, a trained patient is not equal to an untrained patient with less impairment. This has important implications for decisions both on the focus of rehabilitation efforts for chronic stroke, as well as for returning to work and other activities.
Stroke is a leading cause of adult disability, leaving 30% to 66% of patients with lasting motor impairment.1,2 It has long been proposed that motor recovery following stroke is a form of relearning3,4 and that there is considerable overlap between the brain regions involved in both processes.5–7 However, while acquiring skill at a task may allow a patient to perform at the same level as an individual with lesser impairment, this does not necessarily make them equal. For example, well-recovered stroke patients can match the performance of healthy controls on a motor task, but differences exist in the neural networks that underlie performance for each group.8 Furthermore, matched performance does not necessarily imply that both groups have the same ability to continue improving given the opportunity for practice. These differences can complicate judgments regarding patients’ capacity to return to work and other activities,9 and which rehabilitation activities they should focus on. In this article, we propose that acquiring skill through motor training raises a similar issue—a patient who has trained on a task may “appear better,” masking categorical differences in his or her abilities. Consider two hypothetical patients—Patient A, who has mild motor impairment, and Patient B, who is more severely impaired. Patient A performs better in a movement task than Patient B. Patient B then trains at the task, reaching the same performance level as Patient A. If Patient B is now equal to Patient A, he or she should have a similar capacity for further improvement with training. If this is not the case (eg, if Patient B has reached a performance plateau beyond which further training has a limited effect), then a categorical difference remains between these patients despite their matching task performance.
In comparison to healthy individuals, stroke patients select slower voluntary movement speeds when performing movement tasks.10 As speed and accuracy are inherently linked,11 a confound arises when comparing the accuracy of movements performed at different speeds. This limitation makes it difficult to interpret previous results, such as cases where patients improve their accuracy yet decrease their speed.12 In such cases, it is impossible to determine whether a patient improved his or her ability to perform the task (through skill acquisition) or whether he or she simply changed the aspect of performance on which they focused (eg, sacrificed speed for accuracy while remaining at the same overall level of ability). The only way to disambiguate these alternatives is to first derive the speed-accuracy trade-off function (SAF13) for a given task; participants are required to complete the task in a fixed time, allowing accuracy to be measured without the confounding effects of differences in speed. Once derived, skill represents a shift in the SAF.13–15
Here we introduce a serial voluntary isometric elbow force task, a modified version of the serial voluntary isometric pinch task (SVIPT). This task is based on an established laboratory-based model of motor learning in which participants learn to control a cursor by producing isometric forces.13–19 In the task used in the present study, participants controlled a cursor by exerting forces with their elbow flexor muscles, allowing comparisons of performance across participants with greater ranges of impairment than would be possible with the standard (hand controlled) SVIPT paradigm. To control for differences in movement speeds across groups, performance was assessed by comparing the speed-accuracy trade-off pre and post training, using measures of task-level performance (ie, binary success/failure to complete all specified aspects of the task)13–18 and trial-level measures of endpoint error and variability.20 We predicted that the severity of a participant’s motor impairment would limit his or her ability to perform the task and that training may allow him or her to achieve a similar level of performance as an individual with lesser impairment. However, we hypothesized that despite their matching performance, there would be a categorical difference between these individuals; the previously untrained participant with lesser impairment would be able to make large, rapid improvements through training, while the trained participant would not.
[WEB SITE] Despite Weakness, Stroke Patients Can Learn New Tasks Through Rehab Training – Rehab Managment
Even though rehab training doesn’t change the neurological deficits resulting from a stroke, it can help patients learn new motor skills and achieve more independence in their daily lives, a recent study suggests.
Pablo Celnik, MD, director of the Department of Physical Medicine and Rehabilitation at Johns Hopkins, explains the finding more specifically, in a study published in Neurorehabilitation and Neural Repair.
“What we found is that physical rehab is not going to change the weakness caused by damaged brain cells in chronic patients, but it is going to change how well they can perform certain tasks, which can have a huge impact on a patient’s daily life,” Celnik says in a media release from Johns Hopkins Medicine.
The study included 10 chronic stroke patients with Fugi-Meyer Assessment (FMA) scores of >50 out of 66, categorized as having “mild to moderate” functional deficits; 10 patients with FMA scores of <50 out of 66, categorized as having “moderate to severe” impairment.; and 10 able-bodied participants who served as a control group.
All of the study participants were trained to control a simple video game using a using a robotic piece of equipment that held their dominant arm at 90 degrees from their bodies. This eliminated gravity as a burden for those whose arms were weakened by their strokes. The subjects were then taught to use the muscles around their elbow to move a cursor across a screen into small target windows, the release explains.
The participants were then asked to move the cursor through the windows in time with a metronome and completed nine blocks of 10 trials at various speeds—24, 30, 38, 45, 60, 80, 100, 110, and 120 beats per minute.
Next, the participants attended 30-minute training sessions for 4 consecutive days, during which time they were asked to complete five blocks of 30 trials, all at their own pace, and were encouraged to improve their speed and accuracy in each consecutive block. Following the training sessions, the participants’ skill levels were tested again in another skill assessment.
Results showed that while each group’s skill level improved by the end of the training, those with greater motor impairment still demonstrated less skill in both the pre- and post-training assessments. All participants reached a plateau in their improvement around experimental days 3 and 4.
However, the study showed that there was considerable overlap between the post-training performance of the stroke patients and the pre-training performance of groups with less impairment, the release continues.
“When you look at the data, the post-training mild-to-moderate group is indistinguishable from the pre-training control group. And the same was true for post-training scores of those in the moderate-to-severe group and the mild-to-moderate group,” says Robert Hardwick, PhD, postdoctoral fellow in the Department of Neurology at the Johns Hopkins University School of Medicine, in the release.
“This is good news for patients because it means that even when there is little likelihood of further neurological recovery, it means I can still teach them new tasks through training,” Celnik states in the release.
“What is important is to not create false expectations of neurological recovery, while at the same time being hopeful that patients can learn within the boundaries of their neurological deficit to improve their lives.”
[Source(s): Johns Hopkins Medicine, Science Daily]
Selfies are all the rage these days. Using this popular technique of taking photos, Mastercard is trialing a new method of payment that may be helpful to people with disabilities. The company’s new mobile app, called “Identity Check Mobile” (and popularly known as Selfie Pay) allows shoppers to pay for their purchases online by taking a selfie.
This is how it works: The app, when first downloaded, takes a photo of the user, and stores a digitized photo of their face on Mastercard’s servers. When that user is shopping online on their computer, and is ready to pay, they get a notification on their phone to verify the purchase amount. Once they verify it (by simply tapping on the amount), the next screen asks them to take a selfie. The selfie is then matched with the digitized photo of that person’s face, and if there is a match, the purchase is approved. The app also asks the person to blink to ensure that a human is actually taking the selfie, and someone is not just holding a photo of the person in front of the phone camera.
This can be beneficial for people with not very good motor skills, amputees, people with vision impairment or anyone who would want to speed up the checkout process by not typing on the keyboard.
This app is already available in several countries in Europe, and Mastercard says it should be available across the globe starting sometime next year.
[Abstract] Motor Learning in Stroke. Trained Patients Are Not Equal to Untrained Patients With Less Impairment
Background and Objective: Stroke rehabilitation assumes motor learning contributes to motor recovery, yet motor learning in stroke has received little systematic investigation. Here we aimed to illustrate that despite matching levels of performance on a task, a trained patient should not be considered equal to an untrained patient with less impairment.
Methods: We examined motor learning in healthy control participants and groups of stroke survivors with mild-to-moderate or moderate-to-severe motor impairment. Participants performed a series of isometric contractions of the elbow flexors to navigate an on-screen cursor to different targets, and trained to perform this task over a 4-day period. The speed-accuracy trade-off function (SAF) was assessed for each group, controlling for differences in self-selected movement speeds between individuals.
Results: The initial SAF for each group was proportional to their impairment. All groups were able to improve their performance through skill acquisition. Interestingly, training led the moderate-to-severe group to match the untrained (baseline) performance of the mild-to-moderate group, while the trained mild-to-moderate group matched the untrained (baseline) performance of the controls. Critically, this did not make the two groups equivalent; they differed in their capacity to improve beyond this matched performance level. Specifically, the trained groups had reached a plateau, while the untrained groups had not.
Conclusions: Despite matching levels of performance on a task, a trained patient is not equal to an untrained patient with less impairment. This has important implications for decisions both on the focus of rehabilitation efforts for chronic stroke, as well as for returning to work and other activities.
Source: Motor Learning in Stroke
[ARTICLE] Adherence to modified constraint-induced movement therapy: the case for meaningful occupation – Full Text
INTRODUCTION: Modified constraint-induced movement therapy (mCIMT) has been shown to improve function of an affected upper limb post stroke. However, factors influencing adherence of individuals undertaking a mCIMT protocol require further investigation.
AIM: To explore the experience of two participants undergoing a mCIMT protocol and examine factors influencing adherence to the protocol.
METHODS: A qualitative case study design was used. Two participants with upper limb hemiparesis following a stroke were recruited and received mCIMT (two hours of therapy, three days per week for a total of two weeks). During the treatment period, participants were also encouraged to wear the restraint mitt for four hours per day at home.
RESULTS: Participants reported increased confidence and self-esteem following participation, as well as improvements in bi-lateral upper limb function. Participants reported the mCIMT protocol as being highly frustrating. However, motivation to adhere to the protocol was positively influenced by the meaningfulness of the occupations attempted.
CONCLUSION: Although mCIMT can prove frustrating, meaningful occupations may act as a powerful motivator towards adherence to a mCIMT protocol. Further research is required.
WHAT GAP THIS FILLS
Virtual tetherball shows that reducing neural “noise” could help sharpen motor skills.
Exaggerating the visual appearance of mistakes could help people further improve their motor skills after an initial performance peak, according to a new study published inPLOS Computational Biology.
Previous research has shown that manipulating the perception of mistakes can improve motor skills. Dagmar Sternad, Christopher Hasson and colleagues from Northeastern University in Boston and Hokkaido University in Japan set out to examine whether this strategy could further enhance skills after they plateau.
In the study, 42 healthy participants learned a virtual tetherball-like game in which they tried to hit a target with a ball hanging from a pole. After three days, all players reached a performance plateau. Then, for some players, the researchers secretly manipulated the game so that the distance by which the ball missed the target appeared bigger on screen than it actually was.
Participants whose mistakes appeared at least twice as bad as they really were broke past their plateau and continued sharpening their tetherball skills. A control group that remained undeceived showed negligible improvement.
By analyzing the players’ actions using computational learning models, the researchers found that error exaggeration did not change how they made corrections in their throwing techniques. Instead, it reduced random fluctuations, or noise, in nervous system signals that control muscle movement. These findings challenge existing assumptions that such noise cannot be reduced.
The authors point out that their results could help improve strategies to aid people who have reached a motor skills plateau, including elite athletes, healthy elders, stroke patients, and children with dystonia. Future research could reveal the physiological mechanisms underlying the findings.
This work was supported by the National Institute of Child Health and Human Development (NICHD) R01 HD045639, National Institute on Aging (NIA) 1F32 AR061238, National Science Foundation NSF-DMS 0928587, and the U.S. Army Research Institute for the Behavioral and Social Sciences (W5J9CQ-12-C-0046). DS was also supported by a visiting scientist appointment at the Max-Planck Institute for Intelligent Systems in Tübingen, Germany. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the funding organizations. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
The authors have declared that no competing interests exist.
Article: Neuromotor Noise Is Malleable by Amplifying Perceived Errors, Hasson CJ, Zhang Z, Abe MO, Sternad D, PLOS Computational Biology, doi:10.1371/journal.pcbi.1005044, published 4 August 2016.
Applying an electric current to the brain can help recovery from stroke, Oxford University researchers have found.
A team from Oxford’s Nuffield Department of Clinical Neurosciences, led by Professor Heidi Johansen-Berg and Dr Charlotte Stagg, studied the use of transcranial direct current stimulation (tDCS) to support rehabilitation training. The technique involves placing electrodes on the scalp to pass a constant low current through a particular area of the brain.
In this case, the team used a variant called ipsilesional anodal tDCS, where a positive (anodal) current is applied on the side of the brain where damage has occurred. Anodal stimulation has previously been shown to increase the learning of motor skills in healthy people. The hope was that this effect could also be demonstrated in stroke patients, using tDCS to reinforce training that helps patients relearn how to use their body.
Professor Heidi Johansen-Berg said: ‘For stroke patients, longer and more intensive training leads to greater recovery. However, cost and staff availability limit what can be provided. That means that there is increasing interest in therapies that can be used to boost the effects of training.’
The study included twenty-four volunteers who had had a stroke affecting their hand and arm function, split into two groups. Both groups were given nine days of motor training. One group had tDCS during the training sessions, while the other group acted as a control: they were fitted with electrodes but did not receive tDCS.
Before, and at various times up to three months after the training, the volunteers’ motor skills were assessed using established clinical measures to see how much they had improved.
Professor Johansen-Berg said: ‘The assessments before the training were used to establish a baseline score for motor skills. Further assessments could then be used to determine what improvement there was above that baseline.
‘Three months after training, the group that had received tDCS had improved more on our clinical measures than those in the control group. This showed that the patients who had received tDCS were better able to use their hands and arms for movements such as lifting, reaching and grasping objects.’
MRI scanning also showed that those who had had tDCS had more activity in the relevant brain areas for motor skills than the control group.
Study volunteer Jan said: ‘The training was exhausting – like being in the gym every day, but it was huge fun. Even after the first session I felt as if I could do more, even though I was knackered. That made me go back every day, and I found it easier and easier. [The stimulation] didn’t hurt – more like a mild tingle or a static electric shock right on the top of my head. The worst part was that my head itched afterwards!’
She added: ‘I have definitely improved and benefited. People who haven’t seen me say ‘wow – you can move better now’. It definitely helped. I’m just sorry I can’t continue with it. It was so nice to meet a team who had such positive attitudes and who told me it was not too late to improve.’
The research team conclude that there is positive evidence for the use of tDCS to aid stroke recovery but caution that the technique must be proved to have long term benefits not only in clinical measurements but also in the ability to carry out tasks important to daily life. Larger studies, they say, will be needed before this approach could enter routine clinical care.