Encoding a motor memory in the older adult by action observation

The cerebellum and the Mirror Neuron System: A matter of inhibition? From neurophysiological evidence to neuromodulatory implications. A narrative review

Mirror neurons show activity during both the execution (AE) and observation of actions (AO). The Mirror Neuron System (MNS) could be involved during motor imagery (MI) as well. Extensive research suggests that the cerebellum is interconnected with the MNS and may be critically involved in its activities. We gathered evidence on the cerebellum's role in MNS functions, both theoretically and experimentally. Evidence shows that the cerebellum plays a major role during AO and MI and that its lesions impair MNS functions likely because, by modulating the activity of cortical inhibitory interneurons with mirror properties, the cerebellum may contribute to visuomotor matching, which is fundamental for shaping mirror properties. Indeed, the cerebellum may strengthen sensory-motor patterns that minimise the discrepancy between predicted and actual outcome, both during AE and AO. Furthermore, through its connections with the hippocampus, the cerebellum might be involved in internal simulations of motor programs during MI. Finally, as cerebellar neuromodulation might improve its impact on MNS activity, we explored its potential neurophysiological and neurorehabilitation implications.

Dyad motor learning in a wrist-robotic environment: Learning together is better than learning alone

OBJECTIVE

Dyad motor practice is characterized by two learners alternating between physical and observational practice, which can lead to better motor outcomes and reduce practice time compared to physical practice alone. Robot-assisted therapy has become an established neurorehabilitation tool but is limited by high therapy cost and access. Implementing dyad practice in robot-assisted rehabilitation has the potential to improve therapeutic outcomes and/or to achieve them faster. This study aims to determine the effects of dyad practice on motor performance in a wrist-robotic environment to evaluate its potential use in robotic rehabilitation settings.

METHODS

Forty-two healthy participants (18-35 years) were randomized into three groups (n = 14): Dyad practice, physical practice with rest and physical practice without rest. Participants practiced a 2 degree-of-freedom gamified wrist movement task for 20 trials using a custom-made wrist robotic device. A motor performance score (MPS) that captured temporal and spatial time-series kinematics was computed at baseline, the end of training and 24 h later to assess retention.

RESULTS

MPS did not differ between groups at baseline. All groups revealed significant performance gains by the end of training. However, dyads outperformed the other groups at the end of training (p < 0.001) and showed higher retention after 24-h (p = 0.02). Median MPS improved by 46.5% in dyads, 25.3% in physical practice-rest, and 33.6% in physical practice-no rest at the end of training compared to baseline.

CONCLUSION

Compared to physical practice alone, dyad practice leads to superior motor outcomes in a robot-assisted motor learning task. Dyads still outperformed their counterparts 24-h after practice.

IMPACT STATEMENT

Improving motor function in complex motor tasks without increasing required practice time, dyad practice can optimize therapeutic resources. This is particularly impactful in robot-assisted rehabilitation regimens as it would help to improve patients' outcomes and increase care efficiency.

Top-down and bottom-up stimulation techniques combined with action observation treatment in stroke rehabilitation: a perspective

Stroke is a central nervous system disease that causes structural lesions and functional impairments of the brain, resulting in varying types, and degrees of dysfunction. The bimodal balance-recovery model (interhemispheric competition model and vicariation model) has been proposed as the mechanism of functional recovery after a stroke. We analyzed how combinations of motor observation treatment approaches, transcranial electrical (TES) or magnetic (TMS) stimulation and peripheral electrical (PES) or magnetic (PMS) stimulation techniques can be taken as accessorial physical therapy methods on symptom reduction of stroke patients. We suggest that top-down and bottom-up stimulation techniques combined with action observation treatment synergistically might develop into valuable physical therapy strategies in neurorehabilitation after stroke. We explored how TES or TMS intervention over the contralesional hemisphere or the lesioned hemisphere combined with PES or PMS of the paretic limbs during motor observation followed by action execution have super-additive effects to potentiate the effect of conventional treatment in stroke patients. The proposed paradigm could be an innovative and adjunctive approach to potentiate the effect of conventional rehabilitation treatment, especially for those patients with severe motor deficits.

Reflecting on what is "skill" in human motor skill learning

Humans have an exceptional ability to execute a variety of skilled movements. Researchers have been long interested in understanding behavioral and neurophysiological basis of human motor skill learning for advancing both fundamental neuroscientific knowledge and clinical outcomes. However, despite decades of work in this field there is a lack of consensus about what is meant by "skill" in skill learning. With an advent of various task paradigms testing human motor behavior and increasing heterogeneity in motor learning assessments methods, it is very crucial to identify key features of skill in order to avoid any ambiguity that may result in misinterpretation or over-generalization of findings, which could have serious implications for replication and translational research. In this review, we attempt to highlight the features of skill following a historical approach, considering the seminal work that led to the first definitions of skill and including some contemporary concepts emerging from human motor learning research. Overall, based on this literature, we emphasize that skill has some fundamental characteristics, such as- (i) optimal movement selection and execution, (ii) improved movement speed and accuracy, and (iii) reduced movement variability and error. These features of skill can emerge as a consequence of extensive practice/training/learning, thus resulting in an improved performance state beyond baseline levels. Finally we provide some examples of model tasks that can appropriately capture these features of skill, and conclude that any neuroscientific endeavor aimed at understanding the essence of skill in human motor skill learning should focus on these aspects.

Cortically Evoked Movement in Humans Reflects History of Prior Executions, Not Plan for Upcoming Movement

Human motor behavior involves planning and execution of actions, some more frequently. Manipulating probability distribution of a movement through intensive direction-specific repetition causes physiological bias toward that direction, which can be cortically evoked by transcranial magnetic stimulation (TMS). However, because evoked movement has not been used to distinguish movement execution and plan histories to date, it is unclear whether the bias is because of frequently executed movements or recent planning of movement. Here, in a cohort of 40 participants (22 female), we separately manipulate the recent history of movement plans and execution and probe the resulting effects on physiological biases using TMS and on the default plan for goal-directed actions using a timed-response task. Baseline physiological biases shared similar low-level kinematic properties (direction) to a default plan for upcoming movement. However, manipulation of recent execution history via repetitions toward a specific direction significantly affected physiological biases, but not plan-based goal-directed movement. To further determine whether physiological biases reflect ongoing motor planning, we biased plan history by increasing the likelihood of a specific target location and found a significant effect on the default plan for goal-directed movements. However, TMS-evoked movement during preparation did not become biased toward the most frequent plan. This suggests that physiological biases may either provide a readout of the default state of primary motor cortex population activity in the movement-related space, but not ongoing neural activation in the planning-related space, or that practice induces sensitization of neurons involved in the practiced movement, calling into question the relevance of cortically evoked physiological biases to voluntary movements.SIGNIFICANCE STATEMENT Human motor performance depends not only on ability to make movements relevant to the environment/body's current state, but also on recent action history. One emerging approach to study recent movement history effects on the brain is via physiological biases in cortically-evoked involuntary movements. However, because prior movement execution and plan histories were indistinguishable to date, to what extent physiological biases are due to pure execution-dependent history, or to prior planning of the most probable action, remains unclear. Here, we show that physiological biases are profoundly affected by recent movement execution history, but not ongoing movement planning. Evoked movement, therefore, provides a readout of the default state within the movement space, but not of ongoing activation related to voluntary movement planning.

The capacity of action observation to drag the trainees' motor pattern toward the observed model

Action Observation Training (AOT) promotes the acquisition of motor abilities. However, while the cortical modulations associated with the AOT efficacy are well known, few studies investigated the AOT peripheral neural correlates and whether their dynamics move towards the observed model during the training. We administered seventy-two participants (randomized into AOT and Control groups) with training for learning to grasp marbles with chopsticks. Execution practice was preceded by an observation session, in which AOT participants observed an expert performing the task, whereas controls observed landscape videos. Behavioral indices were measured, and three hand muscles' electromyographic (EMG) activity was recorded and compared with the expert. Behaviorally, both groups improved during the training, with AOT outperforming controls. The EMG trainee-model similarity also increased during the training, but only for the AOT group. When combining behavioral and EMG similarity findings, no global relationship emerged; however, behavioral improvements were "locally" predicted by the similarity gain in muscles and action phases more related to the specific motor act. These findings reveal that AOT plays a magnetic role in motor learning, attracting the trainee's motor pattern toward the observed model and paving the way for developing online monitoring tools and neurofeedback protocols.

The value of corticospinal excitability and intracortical inhibition in predicting motor skill improvement driven by action observation

The observation of other's actions represents an essential element for the acquisition of motor skills. While action observation is known to induce changes in the excitability of the motor cortices, whether such modulations may explain the amount of motor improvement driven by action observation training (AOT) remains to be addressed. Using transcranial magnetic stimulation (TMS), we first assessed in 41 volunteers the effect of action observation on corticospinal excitability, intracortical inhibition, and transcallosal inhibition. Subsequently, half of the participants (AOT-group) were asked to observe and then execute a right-hand dexterity task, while the controls had to observe a no-action video before practicing the same task. AOT participants showed greater performance improvement relative to controls. More importantly, the amount of improvement in the AOT group was predicted by the amplitude of corticospinal modulation during action observation and, even more, by the amount of intracortical inhibition induced by action observation. These relations were specific for the AOT group, while the same patterns were not found in controls. Taken together, our findings demonstrate that the efficacy of AOT in promoting motor learning is rooted in the capacity of action observation to modulate the trainee's motor system excitability, especially its intracortical inhibition. Our study not only enriches the picture of the neurophysiological effects induced by action observation onto the observer's motor excitability, but linking them to the efficacy of AOT, it also paves the way for the development of models predicting the outcome of training procedures based on the observation of other's actions.

Immersion Therapy with Head-Mounted Display for Rehabilitation of the Upper Limb after Stroke-Review

Immersive virtual therapy technology is a new method that uses head-mounted displays for rehabilitation purposes. It offers a realistic experience that puts the user in a virtual reality. This new type of therapy is used in the rehabilitation of stroke patients. Many patients after this disease have complications related to the upper extremities that limit independence in their everyday life, which affects the functioning of society. Conventional neurological rehabilitation can be supplemented by the use of immersive virtual therapy. The system allows patients with upper limb dysfunction to perform a motor and task-oriented training in virtual reality that is individually tailored to their performance. The complete immersion therapy itself is researched and evaluated by medical teams to determine the suitability for rehabilitation of the upper limb after a stroke. The purpose of this article is to provide an overview of the latest research (2019-2022) on immersive virtual reality with head-mounted displays using in rehabilitation of the upper extremities of stroke patients.

The Reaching Phase of Feeding and Self-Care Actions Optimizes Action Observation Effects in Chronic Stroke Subjects

BACKGROUND

The Action Observation Therapy (AOT) is a well-established post-stroke rehabilitation treatment based on the theoretical framework of the Mirror Neuron System (MNS) activation. However, AOT protocols are still heterogeneous in terms of video contents of observed actions.

OBJECTIVE

The aim of this study was to analyze electroencephalographic (EEG) recordings in stroke patients during the observation of different videos of task-specific upper limb movements, and to define which category of actions can elicit a stronger cortical activation in the observer's brain.

METHODS

Signals were analyzed from 19 chronic stroke subjects observing customized videos that represented 3 different categories of upper limb actions: Finalized Actions, Non-Finalized Actions, and Control Videos. The Event-Related Desynchronization in the µ and β bands was chosen to identify the involvement of the cerebral cortex: the area of the normalized power spectral density was calculated for each category and, deepening, for the reaching and completion sub-phases of Finalized Actions. For descriptive purposes, the time course of averaged signal power was described. The Kruskal-Wallis test (P < .05) was applied.

RESULTS

The analysis showed a greater desynchronization when subjects observed Finalized Actions with respect to Non-Finalized in all recorded areas; Control videos provoked a synchronization in the same areas and frequency bands. The reaching phase of feeding and self-care actions evoked a greater suppression both in µ and β bands.

CONCLUSIONS

The observation of finalized arm movements seems to elicit the strongest activation of the MNS in chronic stroke patients. This finding may help the clinicians to design future AOT-based stroke rehabilitation protocols.

CLINICAL TRIAL REGISTRATION

Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT04047134.

Immersive Virtual Reality as a Novel Physical Therapy Approach for Nonagenarians: Usability and Effects on Balance Outcomes of a Game-Based Exercise Program

Physical exercise has been recognized as an important strategy in the promotion of healthy aging. Positive effects on older adults' motor ability are brought about by engaging their motor skills and promoting sensorimotor learning and cortical plasticity. These processes could be increased with the use of immersive virtual reality (IVR) technology, since the multisensory stimulation is greater. The aim of this study was to explore the usability and balance effects of an IVR exercise program in community-dwelling nonagenarian people. A sample of 12 women were allocated to an experimental group (EG n = 6; 91.67 ± 1.63 years) and a control group (CG n = 6; 90.83 ± 2.64 years). For 10 weeks, the EG used a commercial IVR exergame three times a week. All the sample completed the program without adverse effects (without Simulator Sickness Questionnaire symptoms). Post-gaming usability was good (System Usability Scale 78.33). The EG improved some balance parameters significantly (Tinetti test: balance (10.97 %; Sig = 0.017), gait (9.23%; Sig = 0.047) and total score (10.20%; Sig = 0.014) and maintained total TUG test times (-0.45%)). There were significant differences between groups (Tinetti test: balance (Sig = 0.004) and total score (Sig = 0.0032)). We successfully demonstrated that IVR training is feasible and is an effective and personalized method to enhance balance and to reduce the risk of falls in community-dwelling nonagenarian women.

Dissociable use-dependent processes for volitional goal-directed reaching

Repetition of specific movement biases subsequent actions towards the practiced movement, a phenomenon known as use-dependent learning (UDL). Recent experiments that impose strict constraints on planning time have revealed two sources of use-dependent biases, one arising from dynamic changes occurring during motor planning and another reflecting a stable shift in motor execution. Here, we used a distributional analysis to examine the contribution of these biases in reaching. To create the conditions for UDL, the target appeared at a designated 'frequent' location on most trials, and at one of six 'rare' locations on other trials. Strikingly, the heading angles were bimodally distributed, with peaks at both frequent and rare target locations. Despite having no constraints on planning time, participants exhibited a robust bias towards the frequent target when movements were self-initiated quickly, the signature of a planning bias; notably, the peak near the rare target was shifted in the frequently practiced direction, the signature of an execution bias. Furthermore, these execution biases were not only replicated in a delayed-response task but were also insensitive to reward. Taken together, these results extend our understanding of how volitional movements are influenced by recent experience.

The effect of backward walking observational training on gait parameters and balance in chronic stroke: randomized controlled study

BACKGROUND

Backward walking (BW) and action observation training may potentially help people at risk of falls. Moreover, action observation training could be a potential intervention to improve gait after a stroke.

AIM

We aimed to identify the effects of BW action observational training (BWOT) on gait parameters and balance in chronic stroke patients.

DESIGN

Randomized, controlled study.

SETTING

Rehabilitation center.

POPULATION

Twenty-four chronic stroke patients were randomly assigned to BWOT (N.=12) and landscape observational training (LOT) (N.=12) groups.

METHODS

The BWOT group performed BW after watching a video of a BW, while the LOT group performed BW training after watching a video of a landscape. Both groups received traditional therapy for 5 days per week and BWOT for 3 days a week for 4 weeks. The primary and secondary outcomes were gait and balance, respectively. Static balance was measured using the 5 Times Sit-To-Stand Test (5TSTS), the center of pressure (COP) displacement, and weight distribution (WD) of the affected side. Dynamic balance was measured using the activity-specific balance confidence (ABC) scale.

RESULTS

The BWOT group showed significant improvements in gait velocity (p=0.001, η²=0.470), step length (P=0.007, η²=0.313), stride lengths (P<0.002, η²=0.431), 5TSTS (P=0.021, η²=0.231), COP velocity (P=0.022, η²=0.226), length (P=0.001, η²=0.504), WD of the affected side (P=0.033, η²=0.193), and ABC score (P=0.023, η²=0.226) than the LOT group.

CONCLUSIONS

The 4-week BWOT training program significantly improved the gait parameters and static and dynamic balance in stroke patients.

CLINICAL REHABILITATION IMPACT

BWOT is an accessible and effective method of rehabilitation training that can also be applied to conventional therapy as a useful method for improving the gait and balance after stroke.

Use of an Observer Tool to Enhance Observers' Learning of Anesthesia Residents During High-Fidelity Simulation: A Randomized Controlled Trial

INTRODUCTION

The growing number of learners implies that all of them cannot play an active role during high-fidelity scenarios. Studies suggest a positive educational value when learners are observers only, but it remains uncertain whether learning outcomes might be improved by using an observer tool (OT).

METHODS

Eighty-nine anesthesia residents were randomized to use an OT (n = 44, OT+; based on a cognitive aid) or not (n = 45, OT-) when not role-playing. The main outcome parameter was the learning outcomes assessed by comparing the change (before-after) in the response score to a questionnaire dedicated to medical knowledge obtained in the OT+ and OT- groups. The impact of using the OT was also assessed by measuring the perceived stress level and the change of the Anesthetists' Non-Technical Skill items values.

RESULTS

At the end of the session, the mean medical knowledge score (mean ± SD) was higher in the OT+ group than in the OT- group (11.4 ± 2.7 vs. 9.6 ± 2.4, respectively, P = 0.0008). The mean Anesthetists' Non-Technical Skill score and level of stress perceived did not differ between groups. Trainees rated similarly the learning value and satisfaction related to the simulation course.

CONCLUSIONS

This study suggests that observing high-fidelity simulation scenarios using an OT based on a cognitive aid increases the medical knowledge gain when compared with that seen in passive observers. This study suggests that the use of an OT improves the educational value of simulation.

The role of mirror mechanism in the recovery, maintenance, and acquisition of motor abilities

While it is well documented that the motor system is more than a mere implementer of motor actions, the possible applications of its cognitive side are still under-exploited, often remaining as poorly organized evidence. Here, we will collect evidence showing the value of action observation treatment (AOT) in the recovery of impaired motor abilities for a vast number of clinical conditions, spanning from traumatological patients to brain injuries and neurodegenerative diseases. Alongside, we will discuss the use of AOT in the maintenance of appropriate motor behavior in subjects at risk for events with dramatic physical consequences, like fall prevention in elderly people or injury prevention in sports. Finally, we will report that AOT can help to tune existing motor competencies in fields requiring precise motor control. We will connect all these diverse dots into the neurophysiological scenario offered by decades of research on the human mirror mechanism, discussing the potentialities for individualization. Empowered by modern technologies, AOT can impact individuals' safety and quality of life across the whole lifespan.

Effects of Mirror Therapy Combined with EMG-Triggered Functional Electrical Stimulation to Improve on Standing Balance and Gait Ability in Patient with Chronic Stroke

This study was performed to evaluate the effects of EMG-triggered functional electrical stimulation on balance and gait ability on patient with Chronic Stroke. A total of 60 chronic stroke patients were divided into mirror treatment and functional electrical (MT-EF) Group, MT group, CON group. Each group performed 60 min a day five times a week for eight weeks. MT-FE group was performed 30 min five times a week for eight weeks in mirror therapy process with EMG-FES. MT group performed 30 min five times a week for eight weeks in mirror therapy process. CON group was performed 30 min five times a week for eight weeks in conservative treatment. To measure the balance ability, Biorescue (COP, LOS), Berg balance scale (BBS) and FRT, and the gait ability test was performed by 10 m walk test. MT-FE group revealed significant differences in COP, LOS, BBS, FRT and 10 m walk test as compared to the MT and CON groups (p < 0.05). Our results showed that MT-FE was more effective on COP, LOS, BBS, FRT and 10 m walk test in patients with chronic stroke. Our results also showed that MT-EF group was more effective on balance and gait ability in patients with chronic stroke. We suggest that this study can be used for intervention data for recovering balance and gait ability in chronic stroke patients.

Transcranial Magnetic Stimulation as a Tool to Investigate Motor Cortex Excitability in Sport

Transcranial magnetic stimulation, since its introduction in 1985, has brought important innovations to the study of cortical excitability as it is a non-invasive method and, therefore, can be used both in healthy and sick subjects. Since the introduction of this cortical stimulation technique, it has been possible to deepen the neurophysiological aspects of motor activation and control. In this narrative review, we want to provide a brief overview regarding TMS as a tool to investigate changes in cortex excitability in athletes and highlight how this tool can be used to investigate the acute and chronic responses of the motor cortex in sport science. The parameters that could be used for the evaluation of cortical excitability and the relative relationship with motor coordination and muscle fatigue, will be also analyzed. Repetitive physical training is generally considered as a principal strategy for acquiring a motor skill, and this process can elicit cortical motor representational changes referred to as use-dependent plasticity. In training settings, physical practice combined with the observation of target movements can enhance cortical excitability and facilitate the process of learning. The data to date suggest that TMS is a valid technique to investigate the changes in motor cortex excitability in trained and untrained subjects. Recently, interest in the possible ergogenic effect of non-invasive brain stimulation in sport is growing and therefore in the future it could be useful to conduct new experiments to evaluate the impact on learning and motor performance of these techniques.

Multiple Motor Learning Processes in Humans: Defining Their Neurophysiological Bases

Learning new motor behaviors or adjusting previously learned actions to account for dynamic changes in our environment requires the operation of multiple distinct motor learning processes, which rely on different neuronal substrates. For instance, humans are capable of acquiring new motor patterns via the formation of internal model representations of the movement dynamics and through positive reinforcement. In this review, we will discuss how changes in human physiological markers, assessed with noninvasive brain stimulation techniques from distinct brain regions, can be utilized to provide insights toward the distinct learning processes underlying motor learning. We will summarize the findings from several behavioral and neurophysiological studies that have made efforts to understand how distinct processes contribute to and interact when learning new motor behaviors. In particular, we will extensively review two types of behavioral processes described in human sensorimotor learning: (1) a recalibration process of a previously learned movement and (2) acquiring an entirely new motor control policy, such as learning to play an instrument. The selected studies will demonstrate in-detail how distinct physiological mechanisms contributions change depending on the time course of learning and the type of behaviors being learned.

Action observation combined with gait training to improve gait and cognition in elderly with mild cognitive impairment A randomized controlled trial

Owing to advancement of medical technology and current knowledge, the population has a longer life expectancy, leading to an increase in the proportion of elderly.

The medical avatar and its role in neurorehabilitation and neuroplasticity: A review

BACKGROUND

One of the most interesting emerging medical devices is the medical avatar - a digital representation of the patient that can be used toward myriad ends, the full potential of which remains to be explored. Medical avatars have been instantiated as telemedical tools used to establish a representation of the patient in tele-space, upon which data about the patient's health can be represented and goals and progress can be visually tracked. Manipulation of the medical avatar has also been explored as a means of increasing motivation and inducing neural plasticity.

OBJECTIVE

The article reviews the literature on body representation, simulation, and action-observation and explores how these components of neurorehabilitation are engaged by an avatar-based self-representation.

METHODS

Through a review of the literature on body representation, simulation, and action-observation and a review of how these components of neurorehabilitation can be engaged and manipulated with an avatar, the neuroplastic potential of the medical avatar is explored. Literature on the use of the medical avatar for neurorehabilitation is also reviewed.

RESULTS

This review demonstrates that the medical avatar has vast potentialities in neurorehabilitation and that further research on its use and effect is needed.

An acute session of motor imagery training induces use-dependent plasticity

Motor imagery, defined as the mental representation of an action without movement-related sensory inputs, is a well-known intervention to improve motor performance. In the current study, we tested whether use-dependent plasticity, a mechanism underlying motor learning, could be induced by an acute session of motor imagery. By means of transcranial magnetic stimulation (TMS) over the left primary motor cortex, we evoked isolated thumb movements in the right hand and assessed corticospinal excitability in the flexor and extensor pollicis brevis muscles. We measured the mean TMS-induced movement direction before and after an acute session of motor imagery practice. In a first experiment, participants of the imagery group were instructed to repeatedly imagine their thumb moving in a direction deviated by 90° from the pre-test movement. This group, but not the control group, deviated the post-training TMS-induced movements toward the training target direction (+44° ± 62° and -1° ± 23°, respectively). Interestingly, the deviation magnitude was driven by the corticospinal excitability increase in the agonist muscle. In a second experiment, we found that post-training TMS-induced movements were proportionally deviated toward the trained direction and returned to baseline 30 minutes after the motor imagery training. These findings suggest that motor imagery induces use-dependent plasticity and, this neural process is accompanied by corticospinal excitability increase in the agonist muscle.

Action Observation Combined With Conventional Training Improves the Rugby Lineout Throwing Performance: A Pilot Study

Combining action observation (AO) and physical practice contributes to motor skill learning, and a number of studies pointed out the beneficial role of AO training in improving the motor performance and the athletes' movement kinematics. The aim of this study was to investigate if AO combined with immediate conventional training was able to improve motor performance and kinematic parameters of a complex motor skill such as the lineout throw, a gesture that represents a key aspect of rugby, that is unique to this sport. Twenty elite rugby players were divided into two groups. The AO group watched a 5-min video-clip of an expert model performing the lineout throw toward a target at 7 m distance and, immediately after the AO, this group executed the conventional training, consisting of six repetitions x five blocks of throws. The CONTROL group performed only the conventional lineout training. Intervention period lasted 4 weeks, 3 sessions/week. The AO group showed significant improvements in throwing accuracy (i.e., number of throws hitting the target), whilst no significant changes were observed in the CONTROL group. As concerns kinematic parameters, hooker's arm mean velocity significantly increased in both groups, but the increase was higher in AO group compared to CONTROL group. Ball velocity significantly increased only in the AO group, whereas ball angle release and ball spinning significantly decreased in both groups, with no differences between groups. Finally, no significant changes in knee and elbow angles were observed. Our results showed that the combination of AO and conventional training was more effective than a conventional training alone in improving the performance of elite rugby players, in executing a complex motor skill, such as the lineout. This combined training led to significant improvements in throwing accuracy and in hooker's and ball's kinematic parameters. Since AO can be easily implemented in combination with conventional training, the results of this study can encourage coaches in designing specific lineout training programs, which include AO cognitive training.

Action observation therapy for improving arm function, walking ability, and daily activity performance after stroke: a systematic review and meta-analysis

Objective:

This study was to investigate the effectiveness of action observation therapy on arm and hand motor function, walking ability, gait performance, and activities of daily living in stroke patients.

Design:

Systematic review and meta-analysis of randomized controlled trials.

Data sources:

Searches were completed in January 2019 from electronic databases, including PubMed, Scopus, the Cochrane Library, and OTseeker.

Review methods:

Two independent reviewers performed data extraction and evaluated the study quality by the PEDro scale. The pooled effect sizes on different aspects of outcome measures were calculated. Subgroup analyses were performed to examine the impact of stroke phases on treatment efficacy.

Results:

Included were 17 articles with 600 patients. Compared with control treatments, the action observation therapy had a moderate effect size on arm and hand motor outcomes (Hedge’s g = 0.564; P < 0.001), a moderate to large effect size on walking outcomes (Hedge’s g = 0.779; P < 0.001), a large effect size on gait velocity (Hedge’s g = 0.990; P < 0.001), and a moderate to large effect size on activities of daily function (Hedge’s g = 0. 728; P = 0.004). Based on subgroup analyses, the action observation therapy showed moderate to large effect sizes in the studies of patients with acute/subacute stroke or those with chronic stroke (Hedge’s g = 0.661 and 0.783).

Conclusion:

This review suggests that action observation therapy is an effective approach for stroke patients to improve arm and hand motor function, walking ability, gait velocity, and daily activity performance.

Action Observation for Neurorehabilitation in Apraxia

Neurorehabilitation and brain stimulation studies of post-stroke patients suggest that action-observation effects can lead to rapid improvements in the recovery of motor functions and long-term motor cortical reorganization. Apraxia is a clinically important disorder characterized by marked impairment in representing and performing skillful movements [gestures], which limits many daily activities and impedes independent functioning. Recent clinical research has revealed errors of visuo-motor integration in patients with apraxia. This paper presents a rehabilitative perspective focusing on the possibility of action observation as a therapeutic treatment for patients with apraxia. This perspective also outlines impacts on neurorehabilitation and brain repair following the reinforcement of the perceptual-motor coupling. To date, interventions based primarily on action observation in apraxia have not been undertaken.

Interaction Between Transcranial Random Noise Stimulation and Observation-Execution Matching Activity Promotes Motor Cortex Excitability

Pathways of the human mirror neuron system are activated during both, action observation and action execution, including lateralized activation of respective areas, as shown by observed right-or left-hand actions. Here, we investigated whether execution-dependent motor cortex excitability is affected by prior interaction between transcranial random noise stimulation (tRNS) and action observation. Sham or real tRNS (1 mA) was applied for 10-min over the left primary motor cortex during action observation. In the main experiments, participants received sham or real tRNS while they watched a video showing repeated tapping tasks, involving either the right-hand (Experiment 1, congruent action observation), or a mirror-reversed video showing the same performance (Experiment 2), followed by action execution of the right-hand. In control Experiments 1–3, participants received real tRNS while observing a perceptual sequence, watching a landscape picture, or observing the left-hand performing the action (the sequence was identical to Experiment 1), followed by action execution of the right-hand. In control Experiment 4, participants received real tRNS during congruent action observation, and then took 6-min rest. Motor-evoked potentials (MEP) were recorded before action observation, a perceptual sequence or a landscape picture, immediately after, and after action execution, or an interval of 6-min, dependent on the respective experimental condition. MEPs in the right first dorsal interosseous muscle increased significantly after real tRNS combined with congruent action observation, and after action execution compared to the sham session in Experiment 1 and control experiments. We conclude that prior interaction between real tRNS and action observation of mirror-matched movements modulates subsequent execution-dependent motor cortex excitability.

Rehabilitation via HOMe Based gaming exercise for the Upper-limb post Stroke (RHOMBUS): protocol of an intervention feasibility trial

INTRODUCTION

Effective interventions to promote upper-limb recovery poststroke are characterised by intensive and repetitive movements. However, the repetitive nature of practice may adversely impact on adherence. Therefore, the development of rehabilitation devices that can be used safely and easily at home, and are motivating, enjoyable and affordable is essential to the health and well-being of stroke survivors.The Neurofenix platform is a non-immersive virtual reality device for poststroke upper-limb rehabilitation. The platform uses a hand controller (a NeuroBall) or arm bands (NeuroBands) that facilitate upper-limb exercise via games displayed on a tablet. The Rehabilitation via HOMe Based gaming exercise for the Upper-limb post Stroke trial aims to determine the safety, feasibility and acceptability of the Neurofenix platform for home-based rehabilitation of the upper-limb poststroke.

METHODS AND ANALYSIS

Thirty people poststroke will be provided with a Neurofenix platform, consisting of a NeuroBall or NeuroBands (dependent on impairment level), seven specially designed games, a tablet and handbook to independently exercise their upper limb for 7 weeks. Training commences with a home visit from a research therapist to teach the participant how to safely use the device. Outcomes assessed at baseline and 8 weeks and 12 weeks are gross level of disability, pain, objectively measured arm function and impairment, self-reported arm function, passive range of movement, spasticity, fatigue, participation, quality of life (QOL) and health service use. A parallel process evaluation will assess feasibility, acceptability and safety of the intervention through assessment of fidelity to the intervention measured objectively through the Neurofenix platform, a postintervention questionnaire and semistructured interviews exploring participants' experiences of the intervention. The feasibility of conducting an economic evaluation will be determined by collecting data on QOL and resource use.

ETHICS AND DISSEMINATION

Ethics approval granted from Brunel University London (10249-MHR-Mar/2018-12322-2). Trial results will be submitted for publication in journals, presented at national and international conferences and distributed to people with stroke.

TRIAL REGISTRATION NUMBER

ISRCTN60291412; Pre-results.

Improvement of Upper Limb Motor Control and Function After Competitive and Noncompetitive Volleyball Exercises in Chronic Stroke Survivors: A Randomized Clinical Trial

OBJECTIVES

To investigate the effects of competitive and noncompetitive volleyball exercises on the functional performance and motor control of the upper limbs in chronic stroke survivors.

DESIGN

Randomized clinical trial.

SETTING

Outpatient rehabilitation center.

PARTICIPANTS

Chronic stroke survivors (N=48).

INTERVENTIONS

Participants were randomly assigned to competitive (n=16) or noncompetitive (n=16) volleyball exercise groups (60min/d volleyball exercise+30min/d traditional rehabilitation, 3d/wk for 7wk) and control group (n=16).

MAIN OUTCOME MEASURES

Reach and grasp motor control measures were evaluated through kinematic analysis. Functional outcomes were assessed via Motor Activity Log, Wolf Motor Function Test (WMFT), Box and Block Test, and Wrist Position Sense Test.

RESULTS

Significant improvement of functional performance was observed in both competitive (P<.0001) and noncompetitive volleyball exercise groups (P<.01), but not in the control group (P>.05), with the exception of WMFT score. Volleyball training, in general, resulted in more efficient spatiotemporal control of reach and grasp functions, as well as less dependence on feedback control as compared to the control group. Moreover, the competitive volleyball exercise group exhibited greater improvement in both functional performance and motor control levels.

CONCLUSIONS

Volleyball team exercises, especially in a competitive format, resulted in enhancing the efficacy of the preprogramming and execution of reach and grasp movements, as well as a shift from feedback to feedforward control of the affected upper limb in chronic stroke survivors. This may well be a potential underlying mechanism for improving functional performance.

Activation of mirror neuron system during gait observation in sub-acute stroke patients and healthy persons

The observation of walking improves gait ability in chronic stroke survivors. It has also been suggested that activation of the mirror neuron system contributes to this effect. However, activation of the mirror neuron system during gait observation has not yet been assessed in sub-acute stroke patients. The objective of this study was to clarify the activation of mirror neuron system during gait observation in sub-acute stroke patients and healthy persons. In this study, we sequentially enrolled five sub-acute stroke patients who had undergone gait training and nine healthy persons. We used fMRI to detect neuronal activation during gait observation. During the observation period in the stroke group, neural activity in the left inferior parietal lobule, right and left inferior frontal gyrus was significantly higher than during the rest period. In the healthy group, neural activity in the left inferior parietal lobule, left inferior frontal gyrus, left middle frontal gyrus, left superior temporal lobule and right and left middle temporal gyrus was significantly higher than during the rest period. The results indicate that the mirror neuron system was activated during gait observation in sub-acute stroke patients who had undergone gait training and also in healthy persons. Our findings suggest that gait observation treatment may provide a promising therapeutic strategy in sub-acute stroke patients who have experienced gait training.

Enhanced Upper Extremity Functions with a Single Session of Action-Observation-Execution and Accelerated Skill Acquisition Program in Subacute Stroke

BACKGROUND

Action-observation-execution (AOE) primes physical training. We examined the immediate effect of AOE with accelerated skill acquisition program (ASAP) on dexterity in subacute stroke.

METHODS

Twelve individuals from 1 to 6 months after stroke were allocated into two groups by matching age and side of stroke. After AOE of 30 minutes, the experimental group received ASAP for 60 minutes whereas the control group received dose-equivalent usual care. The movement time (MT) and functional ability (FA) of hand items of the Wolf motor function test (WMFT), hand functions and global recovery of stroke impact scale (SIS), and intrinsic motivation items of stroke rehabilitation motivation scale were assessed at baseline, after training, and during one-week follow-up. Data were analyzed within and between the groups.

RESULTS

AOE significantly decreased MT of flipping cards of WMFT and hand functions of SIS. Total MT was markedly reduced. AOE with ASAP demonstrated significant group-by-time interactions on MT of lifting pencil of WMFT, total MT, and global recovery. Grip strength, FA, and hand functions were significantly improved only in the experimental group. Both groups improved motivation significantly.

CONCLUSIONS

The AOE with ASAP enhanced dexterity, which persisted for at least a week. This intervention might improve dexterity in subacute stroke.

TRIAL REGISTRATION NUMBER

This trial is registered with TCTR20161007001.

Action observation training modifies brain gray matter structure in healthy adult individuals

Action observation training (AOT) is thought to facilitate motor system function. We applied voxelwise methods to assess the regional modifications of brain gray matter (GM) volumes and white matter (WM) architecture in healthy subjects following AOT and their correlations with improvements at motor and cognitive functional scales. Forty-two righ-handed healthy subjects were randomized into an experimental (AOT-G, n = 20) and a control (C-G, n = 22) group. The training lasted 2 weeks and consisted of 10 sessions of 45 min each during which subjects watched videos of daily-life actions (AOT-G) or landscapes (C-G), alternated by the execution with the right hand of actions presented in the AOT-G videos. At baseline and follow up, motor and cognitive functional measures as well as brain structural MRI scans were obtained. Tensor-based morphometry and tract-based spatial statistics were used to map longitudinal modifications of GM and WM structures and their correlation with functional scales. After training, both groups improved at cognitive tests, whereas the AOT-G also improved hand motor performance. Following training, no modifications of WM diffusion tensor MRI indexes were detected. After training, compared to C-G, AOT-G had increased volume of the left superior frontal gyrus and decreased volume of the right lingual gyrus. Compared to AOT-G, C-G showed increased volume of the right middle frontal gyrus and left inferior temporal gyrus. In AOT-G, GM volume changes correlated with improvements at cognitive tests. Ten-day AOT in healthy individuals modifies GM structure, promoting structural brain plasticity and functional competence.

Turn-Taking and Concurrent Dyad Practice Aid Efficiency but not Effectiveness of Motor Learning in a Balance-Related Task

We studied two forms of dyad practice, compared to individual practice, to determine whether and how practice with a partner impacts performance and learning of a balance task, as well as learners’ subjective perceptions of the practice experience. Participants were assigned to practice alone or in pairs. Partners either alternated turns practicing and observing one another, or they practiced and observed one another concurrently. Concurrent action observation impacted online action execution such that partners tended to show coupled movements, and it was perceived as more interfering than practicing in alternation. These differences did not impact error during practice. While dyad practice was associated with higher ratings of effort than individual practice, all groups improved and showed similar immediate and delayed retention irrespective of whether practice was alone or in pairs. These data provide evidence that a partner’s concurrent practice influences one’s own performance, but not to the detriment (or benefit) of learning. Thus, both alternating and concurrent forms of dyad practice are viable means of enhancing the efficiency, albeit not necessarily the effectiveness, of motor learning.

Boosting the Motor Outcome of the Untrained Hand by Action Observation: Mirror Visual Feedback, Video Therapy, or Both Combined-What Is More Effective?

Action observation (AO) allows access to a network that processes visuomotor and sensorimotor inputs and is believed to be involved in observational learning of motor skills. We conducted three consecutive experiments to examine the boosting effect of AO on the motor outcome of the untrained hand by either mirror visual feedback (MVF), video therapy (VT), or a combination of both. In the first experiment, healthy participants trained either with MVF or without mirror feedback while in the second experiment, participants either trained with VT or observed animal videos. In the third experiment, participants first observed video clips that were followed by either training with MVF or training without mirror feedback. The outcomes for the untrained hand were quantified by scores from five motor tasks. The results demonstrated that MVF and VT significantly increase the motor performance of the untrained hand by the use of AO. We found that MVF was the most effective approach to increase the performance of the target effector. On the contrary, the combination of MVF and VT turns out to be less effective looking from clinical perspective. The gathered results suggest that action-related motor competence with the untrained hand is acquired by both mirror-based and video-based AO.

Action observation effects reflect the modular organization of the human motor system

Action observation, similarly to action execution, facilitates the observer's motor system and Transcranial Magnetic Stimulation (TMS) has been instrumental in exploring the nature of these motor activities. However, contradictory findings question some of the fundamental assumptions regarding the neural computations run by the Action Observation Network (AON). To better understand this issue, we delivered TMS over the observers' motor cortex at two timings of two reaching-grasping actions (precision vs power grip) and we recorded Motor-Evoked Potentials (4 hand/arm muscles; MEPs). At the same time, we also recorded whole-hand TMS Evoked Kinematics (8 hand elevation angles; MEKs) that capture the global functional motor output, as opposed to the limited view offered by recording few muscles. By repeating the same protocol twice, and a third time after continuous theta burst stimulation (cTBS) over the motor cortex, we observe significant time-dependent grip-specific MEPs and MEKs modulations, that disappeared after cTBS. MEKs, differently from MEPs, exhibit a consistent significant modulation across pre-cTBS sessions. Beside clear methodological implications, the multidimensionality of MEKs opens a window on muscle synergies needed to overcome system redundancy. By providing better access to the AON computations, our results strengthen the idea that action observation shares key organizational similarities with action execution.

Motor expertise interacts with physical enactment to enhance action memory

Previous research on action memory showed the advantage for performing the action in memorising the action phrases. We tested if performing the action would help participants with or without motor expertise to memorise the novel action poses. Thirty novel action poses performed by an expert were photographed to constitute memory and interference stimuli. Eighty college students observed to remember the randomly displayed stimuli; however, half were asked to perform the displayed stimuli. Both free-recall and recognition tests were administered immediately and 24 h after the memory task. The results showed that acting was better than observing for memorising the novel action poses, which not only promoted the absolute retention but also alleviated the retention loss caused by interference. Motor expertise enhanced the overall memory performance by promoting a deeper motor encoding. Based on our results, novices should act with (rather than just observe) the model to learn novel motor skills.

Motor Learning Enhances Use-Dependent Plasticity

Motor behaviors are shaped not only by current sensory signals but also by the history of recent experiences. For instance, repeated movements toward a particular target bias the subsequent movements toward that target direction. This process, called use-dependent plasticity (UDP), is considered a basic and goal-independent way of forming motor memories. Most studies consider movement history as the critical component that leads to UDP (Classen et al., 1998; Verstynen and Sabes, 2011). However, the effects of learning (i.e., improved performance) on UDP during movement repetition have not been investigated. Here, we used transcranial magnetic stimulation in two experiments to assess plasticity changes occurring in the primary motor cortex after individuals repeated reinforced and nonreinforced actions. The first experiment assessed whether learning a skill task modulates UDP. We found that a group that successfully learned the skill task showed greater UDP than a group that did not accumulate learning, but made comparable repeated actions. The second experiment aimed to understand the role of reinforcement learning in UDP while controlling for reward magnitude and action kinematics. We found that providing subjects with a binary reward without visual feedback of the cursor led to increased UDP effects. Subjects in the group that received comparable reward not associated with their actions maintained the previously induced UDP. Our findings illustrate how reinforcing consistent actions strengthens use-dependent memories and provide insight into operant mechanisms that modulate plastic changes in the motor cortex.SIGNIFICANCE STATEMENT Performing consistent motor actions induces use-dependent plastic changes in the motor cortex. This plasticity reflects one of the basic forms of human motor learning. Past studies assumed that this form of learning is exclusively affected by repetition of actions. However, here we showed that success-based reinforcement signals could affect the human use-dependent plasticity (UDP) process. Our results indicate that learning augments and interacts with UDP. This effect is important to the understanding of the interplay between the different forms of motor learning and suggests that reinforcement is not only important to learning new behaviors, but can shape our subsequent behavior via its interaction with UDP.

Activity in primary motor cortex during action observation covaries with subsequent behavioral changes in execution

INTRODUCTION

Observing someone else perform a movement facilitates motor planning, execution, and motor memory formation. Rate, an important feature in the execution of repeated movements, has been shown to vary following movement observation although the underlying neural mechanisms are unclear. In the current study, we examined how the rate of self-paced index finger pressing is implicitly modified following passive observation of a similar action performed at a different rate.

METHODS

Fifty subjects performed a finger pressing sequence with their right hand at their own pace before and after passive observation of either a 1-min video depicting the task performed at 3 Hz by someone else or a black screen. An additional set of 15 subjects performed the task in an MRI scanner.

RESULTS

Across all 50 subjects, the spontaneous execution rate prior to video observation had a bimodal distribution with modes around 2 and 4 Hz. Following video observation, the slower subjects performed the task at an increased rate. In the 15 subjects who performed the task in the MRI scanner, we found positive correlation between fMRI signal in the left primary motor strip during passive video observation and subsequent behavioral changes in task performance rate.

CONCLUSION

We conclude that observing someone else perform an action at a higher rate implicitly increases the spontaneous rate of execution, and that this implicit induction is mediated by activity in the contralateral primary motor cortex.

Action observation training of community ambulation for improving walking ability of patients with post-stroke hemiparesis: a randomized controlled pilot trial

Purpose:

To investigate the effects of action observation training involving community-based ambulation for improving walking ability after stroke.

Design:

Randomized, controlled pilot study.

Setting:

Inpatient rehabilitation hospital.

Subjects:

A total of 25 inpatients with post-stroke hemiparesis were randomly assigned to either the experimental group ( n = 12) or control group ( n = 13).

Intervention:

Subjects of the experimental group watched video clips demonstrating four-staged ambulation training with a more complex environment factor for 30 minutes, three times a week for four weeks. Meanwhile, subjects of the control group watched video clips, which showed different landscape pictures.

Main measures:

Walking function was evaluated before and after the four-week intervention using a 10-m walk test, community walk test, activities-specific balance confidence scale, and spatiotemporal gait measures.

Results:

Changes in the values for the 10-m walk test (0.17 ±0.19 m/s vs. 0.05 ±0.08 m/s), community walk test (–151.42 ±123.82 seconds vs. 67.08 ±176.77 seconds), and activities-specific balance confidence (6.25 ±5.61 scores vs. 0.72 ±2.24 scores) and the spatiotemporal parameters (i.e. stride length (19.00 ±11.34 cm vs. 3.16 ±11.20 cm), single support (5.87 ±5.13% vs. 0.25 ±5.95%), and velocity (15.66 ±12.34 cm/s vs. 2.96 ±10.54 cm/s)) indicated a significant improvement in the experimental group compared with the control group. In the experimental group, walking function and ambulation confidence was significantly different between the pre- and post-intervention, whereas the control group showed a significant difference only in the 10-m walk test.

Conclusions:

Action observation training of community ambulation may be favorably used for improving walking function of patients with post-stroke hemiparesis.

Impact of left versus right hemisphere subcortical stroke on the neural processing of action observation and imagery

PURPOSE

Mental training appears to be an attractive tool in stroke rehabilitation. The objective of this study was to investigate whether any differences in the processing of action observation and imagery might exist between patients with left and right hemisphere subcortical strokes.

METHODS

Eighteen patients with strictly subcortical stroke (nine right-hemispheric) underwent a functional magnetic resonance imaging (fMRI) study with an experimental paradigm in which motor acts had to be observed and/or imagined from a first person perspective. Changes in hemodynamic activity were measured using fMRI.

RESULTS

The activity level was found to be higher in the non-lesioned compared to the lesioned hemisphere. Patients with lesions in the left hemisphere had a higher activation level in visual (fusiform and lingual gyri), superior temporal areas and dorsal premotor regions across all performed comparisons than those with right hemisphere lesions. Furthermore they had more vivid imagery experiences and lower scores on the Stroke Impact Scale.

CONCLUSIONS

Patients with left hemisphere subcortical lesions recruit more cortical regions in the processing of action pictures and videos. This recruitment was further enhanced during imagery. This is most likely related to the fact that the lesion touched the dominant hemisphere.

Dysfunction of the Human Mirror Neuron System in Ideomotor Apraxia: Evidence from Mu Suppression

Stroke patients with ideomotor apraxia (IMA) have difficulties controlling voluntary motor actions, as clearly seen when asked to imitate simple gestures performed by the examiner. Despite extensive research, the neurophysiological mechanisms underlying failure to imitate gestures in IMA remain controversial. The aim of the current study was to explore the relationship between imitation failure in IMA and mirror neuron system (MNS) functioning. Mirror neurons were found to play a crucial role in movement imitation and in imitation-based motor learning. Their recruitment during movement observation and execution is signaled in EEG recordings by suppression of the lower (8-10 Hz) mu range. We examined the modulation of EEG in this range in stroke patients with left (n = 21) and right (n = 15) hemisphere damage during observation of video clips showing different manual movements. IMA severity was assessed by the DeRenzi standardized diagnostic test. Results showed that failure to imitate observed manual movements correlated with diminished mu suppression in patients with damage to the right inferior parietal lobule and in patients with damage to the right inferior frontal gyrus pars opercularis-areas where major components of the human MNS are assumed to reside. Voxel-based lesion symptom mapping revealed a significant impact on imitation capacity for the left inferior and superior parietal lobules and the left post central gyrus. Both left and right hemisphere damages were associated with imitation failure typical of IMA, yet a clear demonstration of relationship to the MNS was obtained only in the right hemisphere damage group. Suppression of the 8-10 Hz range was stronger in central compared with occipital sites, pointing to a dominant implication of mu rather than alpha rhythms. However, the suppression correlated with De Renzi's apraxia test scores not only in central but also in occipital sites, suggesting a multifactorial mechanism for IMA, with a possible impact for deranged visual attention (alpha suppression) beyond the effect of MNS damage (mu suppression).

Other-self confusions in action memory: The role of motor processes

People can come to falsely remember performing actions that they have not actually performed. Common accounts of such false action memories have invoked source confusion from the overlap of sensory features but largely ignored the role of motor processes. We addressed this lacuna with a paradigm in which participants first perform (vs. do not perform) actions and then observe another person performing some of the non-performed actions. In this paradigm, observation of videos showing another's actions can later induce false self-attributions of these actions, the observation-inflation effect. Contrary to a sensory-feature account but consistent with a motor-simulation account, we found the effect even with perceptually impoverished action videos in which the majority of sensory features is absent, but motion cues are preserved (Experiment 1). We then created conditions during action observation that should (vs. should not) impede motor simulation. As predicted we found that the effect of observation was reduced when participants executed movements that were incongruent (vs. congruent) with the observed actions (Experiment 2). We discuss the processes that can produce associations of self with observed others' actions and later affect observers' action memory.

Immediate effects of kinesio taping on fixed postural alignment and foot balance in stroke patients

[Purpose] The main aim of this study was to identify the short-term effects of Kinesio taping (KT) on the static body alignment and overall balance function presented by the coordinate and foot balance in stroke patients. [Subjects and Methods] Thirty-eight stroke subjects were randomly allocated into the study groups. The kinematic analysis measured deviation or changes from standard body alignment and foot pressure by the human anatomy-based coordinates were examined using the Shisei Innovation System PA200 ver.9.0. [Results] The glabellas on the front view, larynx on the front view, rt. greater tubercle of the humerus (vertical changes), lt. greater tubercle of the humerus (vertical changes), posterior superior iliac spine, and greater trochanter (horizontal changes) showed statistically significant decreases, indicating dislocation from the axis center, after taping. [Conclusion] The clinical use of KT for stroke patients who have asymmetrical and imbalanced body posture could be an optimal therapeutic approach. Since more evidence based practices are needed, future studies should include large numbers of subjects and examine diverse KT application patterns.