Implicit Motor Learning Research Articles

Explicit and implicit locomotor learning in individuals with chronic hemiparetic stroke.

Motor learning involves both explicit and implicit processes that are fundamental for acquiring and adapting complex motor skills. However, stroke may damage the neural substrates underlying explicit and/or implicit learning, leading to deficits in overall motor performance. Although both learning processes are typically used in concert in daily life and rehabilitation, no gait studies have determined how these processes function together after stroke when tested during a task that elicits dissociable contributions from both. Here, we compared explicit and implicit locomotor learning in individuals with chronic stroke to age- and sex-matched neurologically intact controls. We assessed implicit learning using split-belt adaptation (where two treadmill belts move at different speeds). We assessed explicit learning (i.e., strategy-use) using visual feedback during split-belt walking to help individuals explicitly correct for step length errors created by the split-belts. After the first 40 strides of split-belt walking, we removed the visual feedback and instructed individuals to walk comfortably, a manipulation intended to minimize contributions from explicit learning. We used a multirate state-space model to characterize individual explicit and implicit process contributions to overall behavioral change. The computational and behavioral analyses revealed that, compared with controls, individuals with chronic stroke demonstrated deficits in both explicit and implicit contributions to locomotor learning, a result that runs counter to prior work testing each process individually during gait. Since poststroke locomotor rehabilitation involves interventions that rely on both explicit and implicit motor learning, future work should determine how locomotor rehabilitation interventions can be structured to optimize overall motor learning. NEW & NOTEWORTHY Motor learning involves both implicit and explicit processes, the underlying neural substrates of which could be damaged after stroke. Although both learning processes are typically used in concert in daily life and rehabilitation, no gait studies have determined how these processes function together after stroke. Using a locomotor task that elicits dissociable contributions from both processes and computational modeling, we found evidence that chronic stroke causes deficits in both explicit and implicit locomotor learning.

Is There Task-specificity In Implicit Motor Learning? Comparison Between Individuals With Parkinson's Disease And Controls

Is There Task-specificity In Implicit Motor Learning? Comparison Between Individuals With Parkinson's Disease And Controls

Is there a relationship between resting state connectivity within large-scale functional networks and implicit motor learning impairments in schizophrenia and bipolar disorder?

The aim of this exploratory study is to evaluate whether implicit motor learning impairments observed in schizophrenia (SZ) and bipolar disorder (BD) are associated with the resting state functional connectivity (rs-FC) within large-scale functional networks. The study involved 30 BD patients, 30 SZ patients and 30 healthy controls (HC). Implicit motor learning was evaluated with the use of serial reaction time task (SRTT). Prior to the training patients underwent resting state functional magnetic resonance imaging (rsfMRI) examination. We have measured rs-FC within salience network (SAN), default mode network (DMN), frontoparietal network (FPN), sensorimotor network (SMN), limbic network (LN) and visual network (VIN) and their associations with implicit motor learning indices. rs-FC within SAN, DMN, FPN, SMN, LN and VIN reveal no significant association with implicit motor learning indices. BD, SZ and HC groups did not differ in terms of rs-FC within abovementioned networks. We have shown that in the studied groups SRTT performance could not be predicted by rs-FC within the major large-scale functional networks, i.e., SMN, FPN, VIN, LN, SAN and DMN. The observation of the independence of implicit motor learning from the initial activity of these systems is important for proper understanding of neuronal underpinnings of this process and planning further neuroimaging research on this topic.

A pilot cluster randomised controlled trial, of an IMPlicit learning approach versus standard care, on recovery of mobility following stroke (IMPS)

Objectives To evaluate the delivery of rehabilitation using implicit motor learning principles in an acute stroke setting. Design Pilot, assessor-blind, cluster randomised controlled trial with nested qualitative evaluation. Setting Eight inpatient stroke units, UK. Participants People within 14 days of stroke onset, presenting with lower limb hemiplegia. Interventions Participants at control clusters received usual care. Participants at intervention clusters received rehabilitation using an Implicit Learning Approach (ILA); primarily consisting of reduced frequency instructions/feedback, and promotion of an external focus of attention. Video recording was used to understand the ability of intervention site therapists to adhere to the implicit learning principles, and to compare differences between groups. Measures Ability to recruit and retain clusters/participants; suitability and acceptability of data collection processes; appropriateness of fidelity monitoring methods; and appropriateness of chosen outcome measures. Results Eight stroke units participated, with four assigned to each group (intervention/control). Fifty-one participants were enrolled (intervention group 21; control group 30). Mean time since stroke was 6 days (SD 3.42; 0–14); mean age was 73 years (SD 14, 25–94). Of those approached to take part, 72% agreed. We found clear differences between groups with respect to the frequency and type of instructional statement. The ILA was acceptable to both patients and therapists. Conclusion It is feasible to evaluate the application and effectiveness of motor learning principles within acute stroke rehabilitation, using a cluster randomised design. A larger study is required to evaluate the benefits of each approach; we provide a range of sample size estimates required for this.

Transcranial Direct Current Stimulation (tDCS) on Soccer Players: A Mini-Review

Background: This mini-review explores the application of Transcranial Direct Current Stimulation (tDCS) in enhancing cognitive and motor performance in soccer players. This review synthesizes findings from recent studies focusing on tDCS’s impact on the primary Motor Cortex (M1) and the Dorsolateral Prefrontal Cortex (dlPFC). Results: studies conducted to date show that tDCS can enhance muscle strength, reduce perceived fatigue, and improve well-being in soccer players. For instance, anodal tDCS applied to the primary motor cortex has been shown to temporarily increase quadriceps strength, while stimulation of the dlPFC has improved recovery post-match and enhanced cognitive functions like reaction time and implicit motor learning. Conclusion: the mini-review highlights the need for more targeted research, emphasizing the importance of individualized protocols and advanced neuroimaging techniques to better understand tDCS’s mechanisms and optimize its use in sports. Future directions suggest adopting neurocircuit-based strategies such as RDoC to tailor interventions more precisely to athletes’ needs. This integration could potentially maximize the benefits of tDCS, offering a holistic approach to enhancing athletic performance and recovery in soccer players.

Explicit and implicit locomotor learning in individuals with chronic hemiparetic stroke.

Motor learning involves both explicit and implicit processes that are fundamental for acquiring and adapting complex motor skills. However, stroke may damage the neural substrates underlying explicit and/or implicit learning, leading to deficits in overall motor performance. While both learning processes are typically used in concert in daily life and rehabilitation, no gait studies have determined how these processes function together after stroke when tested during a task that elicits dissociable contributions from both. Here, we compared explicit and implicit locomotor learning in individuals with chronic stroke to age- and sex-matched neurologically intact controls. We assessed implicit learning using split-belt adaptation (where two treadmill belts move at different speeds). We assessed explicit learning (i.e., strategy-use) using visual feedback during split-belt walking to help individuals explicitly correct for step length errors created by the split-belts. The removal of visual feedback after the first 40 strides of split-belt walking, combined with task instructions, minimized contributions from explicit learning for the remainder of the task. We utilized a multi-rate state-space model to characterize individual explicit and implicit process contributions to overall behavioral change. The computational and behavioral analyses revealed that, compared to controls, individuals with chronic stroke demonstrated deficits in both explicit and implicit contributions to locomotor learning, a result that runs counter to prior work testing each process individually during gait. Since post-stroke locomotor rehabilitation involves interventions that rely on both explicit and implicit motor learning, future work should determine how locomotor rehabilitation interventions can be structured to optimize overall motor learning.

A kinematically complex multi-articular motor skill for investigating implicit motor learning.

Here we present a task developed to probe implicit learning of a complex motor skill. This task addresses limitations related to task complexity noted in the literature for methods investigating implicit motor learning, namely the serial reaction time task and continuous tracking task. Specifically, the serial reaction time task is limited by the kinematic simplicity of the required movement and the continuous tracing task faces time-on-task confounds and limitations in the control of task difficulty. The task presented herein addresses these issues by employing a kinematically complex multi-articular movement that controls factors that contribute to task difficulty: stimulus animation velocity and trajectory complexity. Accordingly, our objective was to validate the use of this task in probing implicit motor learning, hypothesizing that participants would learn one of the repeating stimuli implicitly. Participants engaged in six blocks of training whereby they first observed and then reproduced a seemingly random complex trajectory. Repeated trajectories were embedded amongst random trajectories. In line with the hypothesis, error for the repeated trajectories was decreased in comparison to that observed for the random trajectories and 73% of participants were unable to identify one of the repeated trajectories, demonstrating the occurrence of implicit learning. While the task requires minor alteration to optimize learning, ultimately the findings underline the task's potential to investigate implicit learning of a complex motor skill.

Attenuation of implicit motor learning with consecutive exposure to visual errors

Visual errors induced by movement drive implicit corrections of that movement. When similar errors are experienced consecutively, does sensitivity to the error remain consistent each time? This study aimed to investigate the modulation of implicit error sensitivity through continuous exposure to the same errors. In the reaching task using visual error-clamp feedback, participants were presented with the same error in direction and magnitude for four consecutive trials. We found that implicit error sensitivity decreased after exposure to the second error. These results indicate that when visual errors occur consecutively, the sensorimotor system exhibits different responses, even for identical errors. The continuity of errors may be a factor that modulates error sensitivity.

Implicit motor learning in children with autism spectrum disorder: current approaches and future directions.

Motor dysfunction is increasingly being viewed as a core characteristic of autism spectrum disorder (ASD) in children. In particular, children with ASD have difficulty in learning new motor skills and there is a need to develop effective methods to improve this. Previous research has found that children with ASD may retain the ability to implicitly learn motor skills in comparison to their explicit learning of motor skills, which is typically impaired. This literature mini review focuses on summarizing the study of implicit learning in the acquisition of motor skills in children with ASD. First, we briefly introduce several common implicit learning methods in children's motor skill learning. Second, we focus on the role of two important implicit learning approaches in motor skill learning, namely, an external focus of attention and analogy learning. Finally, based on our review of the existing studies, we present an outlook for future research and the areas that need to be improved in the practical teaching of implicit learning in the acquisition of motor skills in children with ASD.

Association of abnormal explicit sense of agency with cerebellar impairment in myoclonus-dystonia.

Non-motor aspects in dystonia are now well recognized. The sense of agency, which refers to the experience of controlling one's own actions, has been scarcely studied in dystonia, even though its disturbances can contribute to movement disorders. Among various brain structures, the cerebral cortex, the cerebellum, and the basal ganglia are involved in shaping the sense of agency. In myoclonus dystonia, resulting from a dysfunction of the motor network, an altered sense of agency may contribute to the clinical phenotype of the condition. In this study, we compared the explicit and implicit sense of agency in patients with myoclonus dystonia caused by a pathogenic variant of SGCE (DYT-SGCE) and control participants. We utilized behavioural tasks to assess the sense of agency and performed neuroimaging analyses, including structural, resting-state functional connectivity, and dynamic causal modelling, to explore the relevant brain regions involved in the sense of agency. Additionally, we examined the relationship between behavioural performance, symptom severity, and neuroimaging findings. We compared 19 patients with DYT-SGCE and 24 healthy volunteers. Our findings revealed that patients with myoclonus-dystonia exhibited a specific impairment in explicit sense of agency, particularly when implicit motor learning was involved. However, their implicit sense of agency remained intact. These patients also displayed grey-matter abnormalities in the motor cerebellum, as well as increased functional connectivity between the cerebellum and pre-supplementary motor area. Dynamic causal modelling analysis further identified reduced inhibitory effects of the cerebellum on the pre-supplementary motor area, decreased excitatory effects of the pre-supplementary motor area on the cerebellum, and increased self-inhibition within the pre-supplementary motor area. Importantly, both cerebellar grey-matter alterations and functional connectivity abnormalities between the cerebellum and pre-supplementary motor area were found to correlate with explicit sense of agency impairment. Increased self-inhibition within the pre-supplementary motor area was associated with less severe myoclonus symptoms. These findings highlight the disruption of higher-level cognitive processes in patients with myoclonus-dystonia, further expanding the spectrum of neurological and psychiatric dysfunction already identified in this disorder.

Effect of a Novel Training Program in Patients With Chronic Shoulder Pain Based on Implicit Motor Learning: Pilot and Feasibility Study.

Implicit motor learning has been shown to be effective for learning sports-related motor skills. It facilitates automaticity of movements and thereby improves performance in multitasking and high-pressure environments. Motor learning to develop motor skills and neuroplastic capacities is not sufficiently incorporated in musculoskeletal rehabilitation. Especially in patients with chronic pain conditions like shoulder pain this approach might benefit over traditional exercise programs. The aim of this study was to investigate the feasibility and clinical outcome of a new implicit motor learning exercise program in a group of patients with chronic shoulder pain. Pilot and feasibility cohort study. Twenty-six patients with chronic shoulder pain performed a 6-week home exercise program with weekly remote follow up by a physiotherapist. The program comprised five exercises designed to challenge overall body balance, simultaneously engaging the upper limbs in a range of reaching tasks. The tasks included reaching above the head, at and below waist level, in various directions. No instructions on correct performance were provided to foster external focus. Feasibility was assessed by (1) recruitment rate, (2) follow up rate, (3) subjective experience, (4) self-reported adverse events and (5) self-reported adherence of subjects. Clinical effects of the program were assessed with (1) the Shoulder Pain and Disability Index (SPADI), (2) the Auto-Constant score, (3) the numeric rating scale (NRS) at rest and at night, (4) the patient specific functional scale (PSFS), (5) the avoidance endurance questionnaire (AEQ), (6) patient acceptable symptom state (PASS) and (7) a global rating of change (GROC). The study protocol was feasible in terms of follow up rate (16w for 28 patients), exercise adherence (77.1%± 29.41), and adverse events (no serious, 5 light adverse events). Statistically significant improvements were observed for SPADI (p<0.001), NRS at rest (p=0.033), at night (p=0.29), PSFS (p<0.001) and PASS (p<0.001) after only six weeks training. This study reveals promising results of another way of looking at exercise for patients with chronic shoulder pain. Both feasibility and clinical effects of the program on pain and function was acceptable. Future studies should incorporate a control group, provide longer follow up and include objective measurements. 2b.

The Impact of Implicit Motor Learning on Motor Performance

This paper systematically explores the impact of implicit motor learning on motor performance, including the concepts and theoretical foundations of implicit motor learning, its relationship with the development of motor skills and motor performance, the effects and practical applications of implicit motor learning training, as well as the moderating role of psychological factors. Research findings suggest that implicit motor learning training plays a crucial role in enhancing motor skills and promoting rehabilitation, with potential value in sports education. Future research can further investigate individual differences, neural mechanisms, optimization of clinical applications, intervention strategies for psychological factors, and interdisciplinary studies, among other aspects.

Development of an Elliptical Perturbation System that provides unexpected perturbations during elliptical walking (the EPES system)

Background‘Perturbation-based balance training’ (PBBT) is a training method that was developed to improve balance reactive responses to unexpected balance loss. This training method is more effective in reducing fall rates than traditional balance training methods. Many PBBTs are performed during standing or treadmill walking which targeted specifically step reactive responses, we however, aimed to develop and build a mechatronic system that can provide unexpected perturbation during elliptical walking the Elliptical Perturbation System (the EPES system), with the aim of improving specifically the trunk and upper limbs balance reactive control.MethodsThis paper describes the development, and building of the EPES system, using a stationary Elliptical Exercise device, which allows training of trunk and upper limbs balance reactive responses in older adults.ResultsThe EPES system provides 3-dimensional small, controlled, and unpredictable sudden perturbations during stationary elliptical walking. We developed software that can identify a trainee’s trunk and arms reactive balance responses using a stereo camera. After identifying an effective trunk and arms reactive balance response, the software controls the EPES system motors to return the system to its horizontal baseline position after the perturbation. The system thus provides closed-loop feedback for a person’s counterbalancing trunk and arm responses, helping to implement implicit motor learning for the trainee. The pilot results show that the EPES software can successfully identify balance reactive responses among participants who are exposed to a sudden unexpected perturbation during elliptical walking on the EPES system.ConclusionsEPES trigger reactive balance responses involving counter-rotation action of body segments and simultaneously evoke arms, and trunk reactive response, thus reactive training effects should be expected.

Implicit Motor Learning Strategies Benefit Dual-Task Performance in Patients with Stroke.

Background and Objectives: In stroke rehabilitation, the use of either implicit or explicit learning as a motor learning approach during dual tasks is common, but it is unclear which strategy is more beneficial. This study aims to determine the benefits of implicit versus explicit motor learning approaches in patients with stroke. Materials and Methods: Seventeen patients with stroke and 21 control participants were included. Motor learning was evaluated using the Serial Reaction Time Task (SRTT) in the context of dual-task conditions. The SRTT was conducted on two separate days: one day for implicit learning conditions and the other day for explicit learning conditions. Under the explicit learning conditions, a task rule was given to the participants before they started the task, but not under the implicit learning conditions. Learning scores were calculated for both implicit and explicit learning, and these scores were then compared within groups for patients with stroke and controls. We calculated the difference in learning scores between implicit and explicit learning and conducted a correlation analysis with the Trail Making Test (TMT) Parts A and B. Results: Learning scores on the SRTT were not different between implicit and explicit learning in controls but were significantly greater in patients with stroke for implicit learning than for explicit learning. The difference in learning scores between implicit and explicit learning in patients with stroke was correlated with TMT-A and showed a correlation trend with TMT-B. Conclusions: Implicit learning approaches may be effective in the acquisition of motor skills with dual-task demands in post-stroke patients with deficits in attention and working memory.

When practice does not make a perfect - paradoxical learning curve in schizophrenia and bipolar disorder revealed by different serial reaction time task variants.

Our previous studies identified a paradoxical implicit motor learning curve in schizophrenia (SZ) and bipolar disorder (BD) patients. This study aimed to verify whether those previously observed deficits may be captured by a new version of the ambidextrous serial reaction time task (SRTT), prepared for use in the MRI. This study involved 186 participants. A total of 97 participants (33 BD, 33 SZ, and 31 healthy controls, HCs) completed the original, unlimited time response variant of SRTT. A total of 90 individuals (30 BD, 30 SZ, and 30 HCs) underwent a newer, limited response time version of this procedure. There was no significant difference in terms of implicit motor learning indices between both limited and unlimited response time SRTT. Compared to HCs, SZ, and BD patients presented decreased indices of implicit motor learning. Both clinical groups showed a paradoxical learning pattern that differed significantly from the HCs. Moreover, in the SZ group, the pattern depended on the hand performing SRTT. The limited response time SRTT variant allowed us to replicate the findings of disrupted implicit motor learning in SZ and BD. The use of this paradigm in further neuroimaging studies may help to determine the neuronal underpinnings of this cognitive dysfunction in the abovementioned clinical groups.

Moderate-intensity cardiovascular exercise performed before motor practice attenuates offline implicit motor learning in stroke survivors but not age-matched neurotypical adults.

The acute impact of cardiovascular exercise on implicit motor learning of stroke survivors is still unknown. We investigated the effects of cardiovascular exercise on implicit motor learning of mild-moderately impaired chronic stroke survivors and neurotypical adults. We addressed whether exercise priming effects are time-dependent (e.g., exercise before or after practice) in the encoding (acquisition) and recall (retention) phases. Forty-five stroke survivors and 45 age-matched neurotypical adults were randomized into three sub-groups: BEFORE (exercise, then motor practice), AFTER (motor practice, then exercise), and No-EX (motor practice alone). All sub-groups practiced a serial reaction time task (five repeated and two pseudorandom sequences per day) on three consecutive days, followed 7days later by a retention test (one repeated sequence). Exercise was performed on a stationary bike, (one 20-min bout per day) at 50% to 70% heart rate reserve. Implicit motor learning was measured as a difference score (repeated-pseudorandom sequence response time) during practice (acquisition) and recall (delayed retention). Separate analyses were performed on the stroke and neurotypical groups using linear mixed-effects models (participant ID was a random effect). There was no exercise-induced benefit on implicit motor learning for any sub-group. However, exercise performed before practice impaired encoding in neurotypical adults and attenuated retention performance of stroke survivors. There is no benefit to implicit motor learning of moderately intense cardiovascular exercise for stroke survivors or age-matched neurotypical adults, regardless of timing. Practice under a high arousal state and exercise-induced fatigue may have attenuated offline learning in stroke survivors.

Evidence of Implicit and Explicit Motor Learning during Gait Training with Distorted Rhythmic Auditory Cues

Gait training with rhythmic auditory cues contains motor learning mechanisms that are weighted more explicitly than implicitly. However, various clinical populations may benefit from a shift to gait training with greater implicit motor learning mechanisms. To investigate the ability to incorporate more implicit-weighted motor learning processes during rhythmic auditory cueing, we attempted to induce error-based recalibration using a subtly varying metronome cue for naïve unimpaired young adults. We assessed the extent of implicit and explicit retention after both an isochronous metronome and subtly varying metronome frequency during treadmill and overground walking. Despite 90% of participants remaining unaware of the changing metronome frequency, participants adjusted their cadence and step length to the subtly changing metronome, both on a treadmill and overground (p < 0.05). However, despite evidence of both implicit and explicit processes involved with each metronome (i.e., isochronous and varying), there were no between-condition differences in implicit or explicit retention for cadence, step length, or gait speed, and thus no increased implicit learning advantage with the addition of error-based recalibration for young, unimpaired adults.

Metacognitive judgments during visuomotor learning reflect the integration of error history.

People form metacognitive representations of their own abilities across a range of tasks. How these representations are influenced by errors during learning is poorly understood. Here, we ask how metacognitive confidence judgments of performance during motor learning are shaped by the learner's recent history of errors. Across four motor learning experiments, our computational modeling approach demonstrated that people's confidence judgments are best explained by a recency-weighted averaging of visually observed errors. Moreover, in the formation of these confidence estimates, people appear to reweight observed motor errors according to a subjective cost function. Confidence judgments were adaptive, incorporating recent motor errors in a manner that was sensitive to the volatility of the learning environment, integrating a shallower history when the environment was more volatile. Finally, confidence tracked motor errors in the context of both implicit and explicit motor learning but only showed evidence of influencing behavior in the latter. Our study thus provides a novel descriptive model that successfully approximates the dynamics of metacognitive judgments during motor learning.NEW & NOTEWORTHY This study examined how, during visuomotor learning, people's confidence in their performance is shaped by their recent history of errors. Using computational modeling, we found that confidence incorporated recent error history, tracked subjective error costs, was sensitive to environmental volatility, and in some contexts may influence learning. Together, these results provide a novel model of metacognitive judgments during motor learning that could be applied to future computational and neural studies at the interface of higher-order cognition and motor control.

Experts' perspectives on how to promote implicit and explicit motor learning in children: A mixed-methods study.

Little is known about how motor learning strategies (MLSs) can promote implicit and explicit motor learning processes. This study aimed to explore experts' perspectives on therapists' use of MLSs to promote specific learning processes in children with and without developmental coordination disorder (DCD). In this mixed-methods study, two consecutive digital questionnaires were used to ascertain the opinions of international experts. Questionnaire 2 explored the findings of Questionnaire 1 in greater depth. In order to reach a certain level of agreement about the classification of MLSs as promoting either (more) implicit or (more) explicit motor learning, 5-point Likert scales were used in addition to open-ended questions. The open-ended questions were analysed with a conventional analysis approach. Open coding was performed by two reviewers independently. Categories and themes were discussed within the research team, taking both questionnaires as one dataset. Twenty-nine experts from nine different countries with different backgrounds in research, education and/or clinical care completed the questionnaires. The results of the Likert scales showed large variation. Two themes emerged from the qualitative analyses: (1) Experts found it difficult to classify MLSs as promoting either implicit or explicit motor learning, and (2) experts stressed the need for clinical decisionmaking when choosing MLSs. Insufficient insight was gained into how MLSs could promote (more) implicit or (more) explicit motor learning in children in general and in children with DCD specifically. But this study demonstrated the importance of clinical decisionmaking to model and adapt MLSs to child, task and environment, with therapists' knowledge of MLSs being an important prerequisite. Research is needed to better understand the various learning mechanisms of children and how MLSs can be used to manipulate these mechanisms.

The use of enhanced intrinsic feedback for motor learning in stroke survivors: Clinical trial protocol

BackgroundStroke can lead to lasting sensorimotor deficits of the upper limb (UL) persisting into the chronic phase despite intensive rehabilitation. A major impairment of reaching after stroke is a decreased range of active elbow extension, which in turn leads to the use of compensatory movements. Retraining movement patterns relies on cognition and motor learning principles. Implicit learning may lead to better outcomes than explicit learning. Error augmentation (EA) is a feedback modality based on implicit learning resulting in improved precision and speed of UL reaching movements in people with stroke. However, accompanying changes in UL joint movement patterns have not been investigated. The objective of this study is to determine the capacity for implicit motor learning in people with chronic stroke and how this capacity is affected by post-stroke cognitive impairments. MethodsFifty-two subjects who have chronic stroke will practice reaching movements 3×/wk. for 9 wk. in a virtual reality environment. Participants will be randomly allocated to 1 of 2 groups to train with or without EA feedback. Outcome measures (pre-, post- and follow-up) will be: endpoint precision, speed, smoothness, and straightness and joint (UL and trunk) kinematics during a functional reaching task. The degree of cognitive impairment, lesion profile, and integrity of descending white matter tracts will be related to training outcomes. ConclusionsThe results will inform us which patients can best benefit from training programs that rely on motor learning and utilize enhanced feedback.Trial status: Ethical approval for this study was finalized in May 2022. Recruitment and data collection is actively in progress and is planned to finish in 2026. Data analysis and evaluation will occur subsequently, and the final results will be published.