Motor Skill Learning Research Articles

Distinct mechanisms for online and offline motor skill learning across human development.

The human central nervous system (CNS) undergoes tremendous changes from childhood to adulthood and this may affect how individuals at different stages of development learn new skills. Here, we studied motor skill learning in children, adolescents, and young adults to test the prediction that differences in the maturation of different learning mechanisms lead to distinct temporal patterns of motor learning during practice and overnight. We found that overall learning did not differ between children, adolescents, and young adults. However, we demonstrate that adult-like skill learning is characterized by rapid and large improvements in motor performance during practice (i.e., online) that are susceptible to forgetting and decay over time (i.e., offline). On the other hand, child-like learning exhibits slower and less pronounced improvements in performance during practice, but these improvements are robust against forgetting and lead to gains in performance overnight without further practice. The different temporal dynamics of motor skill learning suggest an engagement of distinct learning mechanisms in the human CNS during development. In conclusion, adult-like skill learning mechanisms favor online improvements in motor performance whereas child-like learning mechanisms favors offline behavioral gains. RESEARCH HIGHLIGHTS: Many essential motor skills, like walking, talking, and writing, are acquired during childhood, and it is colloquially thought that children learn better than adults. We investigated dynamics of motor skill learning in children, adolescents, and young adults. Adults displayed substantial improvements during practice that was susceptible to forgetting over time. Children displayed smaller improvements during practice that were resilient against forgetting. The distinct age-related characteristics of these processes of acquisition and consolidation suggest that skill learning relies on different mechanisms in the immature and mature central nervous system.

Dynamics of Motor Skill Learning in American and Israeli Toddlers With Varied Language Proficiency.

The aim of the present study was twofold: to determine if deficits in motor skill proficiency and learning were present in 2-year-old children identified with early expressive language delay compared to peers without the delay, and to distinguish how motor skill proficiency and learning behaviors may manifest differently across culturally and linguistically diverse backgrounds. The study involved 54 children (24-36 months of age), 23 of whom were identified as having an expressive language delay. Furthermore, 16 participants were American and English-speaking and 38 were Israeli and Hebrew-speaking. After motor and language skill proficiency was assessed using a variety of measures, each child and participating parent were introduced to a nonsymmetrical-shaped insertion task so that motor learning skills could be observed. This block insertion task was observed for each child at three time points and included a transfer task (same task, new nonsymmetrical shape). Children with early expressive language delay were statistically significantly more likely to exhibit deficits in fine-motor proficiency than peers without language delay, regardless of country of origin or language spoken. Furthermore, participants with language delay demonstrated significantly higher error rates in transfer task completion compared with peers. Finally, participants in the U.S. sample indicated lower fine-motor skills and higher error rates than those in the Israeli sample. Differences in motor skill proficiency were universally associated with language delay status, indicating support for the notion that language acquisition deficits may extend beyond the linguistic system even in young children identified as late talkers.

The affective response to positive performance feedback is associated with motor learning.

Motor skill learning and performance are improved when successful actions are paired with extrinsic rewards, such as money. Positive feedback indicating successful task performance is thought to induce intrinsic reward associated with goal attainment, evidenced by increases in positive affect that correlate with neural reward signaling. However, it is not clear whether the subjective, internal reward processes elicited by positive feedback promote motor learning and performance.Here, we tested the hypothesis that intrinsic reward elicited by positive feedback promotes motor learning and performance. Participants practiced a visuomotor interception task using a joystick, and received feedback during practice indicating success or failure depending on their accuracy. During practice, the accuracy demands were adapted to control and vary the frequency of positive feedback across randomly ordered blocks of practice at either 50%, 70%, or 90%. Performance was measured for each condition as the average accuracy during practice. Learning was estimated by measuring the accuracy pre and post practice in the absence of feedback. We queried participants periodically on their enjoyment of the task to index affective responses to performance feedback.The intrinsic reward elicited by positive feedback, operationalized by the increase in enjoyment immediately following positive versus negative feedback, was positively correlated with learning from pre to post practice. However, increasing the overall amount of positive feedback by lower accuracy demands did not improve performance. These results suggest that experiencing intrinsic reward due to positive feedback benefits motor learning only when it is contingent on good performance.

Determining the optimal challenge point for learning motor skills in children with attention deficit/hyperactivity disorder

The purpose of this study was to investigate the optimal challenge point for learning motor skills in children with and without attention deficit/hyperactivity disorder (ADHD). Ninety-six 9- to 10-year-old children, including 48 children with ADHD and 48 neurotypical children, were randomly assigned to one of four practice groups with varying levels of nominal and functional task difficulty. They performed 63 trials of a dart throwing task in the acquisition phase and 18 trials in the retention and transfer tests a day later. The results showed that neurotypical children outperformed children with ADHD in all phases of the study. Both groups improved in the acquisition phase and performed better in the retention and transfer tests. Interestingly, low nominal task difficulty was associated with better learning for both groups, despite lower average performance for children with ADHD. Thus, despite their performance differences, we did not find a difference in the effective challenge point between children with ADHD and their neurotypical peers.

Enhancing motor skill learning through multiple sessions of online high-definition transcranial direct current stimulation in healthy adults: insights from EEG power spectrum.

The purpose of this study was to evaluate the influence of high-definition transcranial direct current stimulation (HD-tDCS) on finger motor skill acquisition. Thirty-one healthy adult males were randomly assigned to one of three groups: online HD-tDCS (administered during motor skill learning), offline HD-tDCS (delivered before motor skill learning), and a sham group. Participants engaged in a visual isometric pinch task for three consecutive days. Overall motor skill learning and speed-accuracy tradeoff function were used to evaluate the efficacy of tDCS. Electroencephalography was recorded and power spectral density was calculated. Both online and offline HD-tDCS total motor skill acquisition was significantly higher than the sham group (P < 0.001 and P < 0.05, respectively). Motor skill acquisition in the online group was higher than offline (P = 0.132, Cohen's d =1.46). Speed-accuracy tradeoff function in the online group was higher than both offline and sham groups in the post-test. The online group exhibited significantly lower electroencephalography activity in the frontal, fronto-central, and centro-parietal alpha band regions compared to the sham (P < 0.05). The findings suggest that HD-tDCS application can boost finger motor skill acquisition, with online HD-tDCS displaying superior facilitation. Furthermore, online HD-tDCS reduces the power of alpha rhythms during motor skill execution, enhancing information processing and skill learning efficiency.

The Effect of Contextual Interference on the Acquisition and Learning of Motor Skill with an Emphasis on Cognitive Flexibility

Background: The effect of contextual interference (CI) on motor skill learning may be influenced by various factors, such as cognitive abilities. Objectives: The purpose of the current research was to investigate the effect of CI on the acquisition and learning of soccer skills, with an emphasis on the role of cognitive flexibility (CF). Methods: Eighty students, aged 9 - 12 years, were randomly selected and administered the Wisconsin Card Sorting Test. From this group, 60 students who scored the highest and lowest points were selected as the final subjects. After completing the pre-test on Moore-Christine's pass, shoot, and dribble skills, the subjects were divided into four groups of 15 participants each (high CF with Random Practice (RP) and Blocked Practice (BP), low CF with RP and BP). The subjects then engaged in practice sessions according to their assigned protocols for three sessions, with each session consisting of three blocks of 12 trials across all three skills—passing, shooting, and dribbling. Following the practice, acquisition, immediate retention, delayed retention, and transfer tests were conducted. Results: The results showed that practice in all four groups had significant beneficial effects on the acquisition and learning of skills. Additionally, the high CF with RP group demonstrated better performance in all skills compared to the other groups. Conclusions: Therefore, it can be concluded that RP may be more beneficial for individuals with higher CF. Teachers and educators should consider this when teaching sports skills.

Human α-synuclein aggregation activates ferroptosis leading to parvalbumin interneuron degeneration and motor learning impairment.

The accumulation of α-synuclein induces neuronal loss in midbrain nuclei and leads to the disruption of motor circuits, while the pathology of α-synuclein in cortical regions remains elusive. To better characterize cortical synucleinopathy, here we generate a mouse model with the overexpression of human α-synuclein in the primary motor cortex (M1) of mice. A combination of molecular, in vivo recording, and behavioral approaches reveal that cortical expression of human α-synuclein results in the overexcitation of cortical pyramidal neurons (PNs), which are regulated by the decreased inhibitory inputs from parvalbumin-interneurons (PV-INs) to impair complex motor skill learning. Further mechanistic dissections reveal that human α-synuclein aggregation activates ferroptosis, contributing to PV-IN degeneration and motor circuit dysfunction. Taken together, the current study adds more knowledge to the emerging role and pathogenic mechanism of ferroptosis in neurodegenerative diseases.

Link between Cognitive Abilities and Physical Activity: Cognitive Training in Physical Rehabilitation

Patients in physical rehabilitation programs need to learn motor skills that they previously performed automatically. Therefore, understating learning processes involved in physical rehabilitation may be useful to implement rehabilitation programs in terms of achieved goals, recovery speed, and patient satisfaction.

Millisecond-scale motor control precedes sensorimotor learning in Bengalese finches.

A key goal of the nervous system in young animals is to learn motor skills. Songbirds learn to sing as juveniles, providing a unique opportunity to identify the neural correlates of skill acquisition. Prior studies have shown that spike rate variability decreases during song acquisition, suggesting a transition from rate-based neural control to the millisecond-precise motor codes known to underlie adult vocal performance. By quantifying how the ensemble of spike patterns fired by cortical neurons (the "neural vocabulary") and the relationship between spike patterns and song acoustics (the "neural code") change during song acquisition, we quantified how vocal control changes across learning in juvenile Bengalese finches. We found that despite the expected drop in rate variability (a learning-related change in spike vocabulary), the precision of the neural code in the youngest singers is the same as in adults, with 1-2 millisecond variations in spike timing transduced into quantifiably different behaviors. In contrast, fluctuations of firing rates on longer timescales fail to affect the motor output. The consistent presence of millisecond-scale motor coding during changing levels of spike rate and behavioral variability supports the view that variability early in learning stems from deliberate motor exploration rather than imprecise motor control.

Advancing robots with greater dynamic dexterity: A large-scale multi-view and multi-modal dataset of human-human throw&amp;catch of arbitrary objects

Learning and imitating behavioral intelligence from human demonstrations is a promising approach towards the intuitive programming of robots for enhanced dynamic dexterity. However, there has been no publicly available dataset in this domain. To address this gap, we introduce the first large-scale dataset and recording framework specifically designed for studying human collaborative dynamic dexterity in throw&amp;catch tasks. The dataset, named H2TC, contains 15,000 multi-view and multi-modal synchronized recordings of diverse Human-Human Throw-and-Catch activities. It involves 34 human subjects with typical motor abilities and a variety of 52 objects frequently manipulated through throw&amp;catch in domestic and/or industrial scenarios. The dataset is supplemented with a hierarchy of manually annotated semantic and dense labels, such as the ground truth human body, hand and object motions captured with specialized high-precision motion tracking systems. These rich annotations make the dataset well-suited for a wide range of robot studies, including both low-level motor skill learning and high-level cognitive planning and recognition. We envision that the proposed dataset and recording framework will facilitate learning pipelines to extract insights on how humans coordinate both intra- and interpersonally to throw and catch objects, ultimately leading to the development of more capable and collaborative robots. The dataset, along with a suite of utility tools, such as those for visualization and annotation, can be accessed from our project page at https://h2tc-roboticsx.github.io/ .

Sharing Our World: Impact of Group Motor Skill Learning on Joint Attention in Children with Autism Spectrum Disorder.

Impaired joint attention is a common feature of autism spectrum disorder (ASD), affecting social interaction and communication. We explored if group basketball learning could enhance joint attention in autistic children, and how this relates to brain changes, particularly white matter development integrity. Forty-nine autistic children, aged 4-12 years, were recruited from special education centers. The experimental group underwent a 12-week basketball motor skill learning, while the control group received standard care. Eye-tracking and brain scans were conducted. The 12-week basketball motor skill learning improved joint attention in the experimental group, evidenced by better eye tracking metrics and enhanced white matter integrity. Moreover, reduced time to first fixation correlated positively with decreased mean diffusivity of the left superior corona radiata and left superior fronto-occipital fasciculus in the experimental group. Basketball-based motor skill intervention effectively improved joint attention in autistic children. Improved white matter fiber integrity related to sensory perception, spatial and early attention function may underlie this effect. These findings highlight the potential of group motor skill learning within clinical rehabilitation for treating ASD.

The impact of observing lecturer hand motor actions on the learning of cognitive skills in higher education

Class demonstrations where the lecturer's hand motor actions are observable generally have a positive effect on the learning of motor skills because they trigger an effortless process of embodied simulations. Whether the learning of cognitive skills is likewise affected by such visualisations is yet to be investigated and might depend on the learning content as well as other factors. This study aimed to investigate whether showing the lecturer's hand via a document camera during an introductory financial accounting class affects student learning (transfer performance), cognitive load responses, and note-taking behaviour compared to a writing pad where the lecturer's hand is not visible. The study utilised a quasi-experimental design in an in-person setting, with a pre-test and post-test comparison of two groups of participants: one group that viewed a lecture video without the lecturer's hand being visible (n = 509), and another group that viewed the same lecture with the lecturer's hand being visible (n = 571). The results showed that the with-hand group had a significantly higher increase in test scores compared to the without-hand group. However, the visibility of the hand did not significantly impact cognitive load or note-taking behaviour. The findings have important practical implications for education, as incorporating non-verbal cues such as the lecturer's hand may effectively enhance learning cognitive skills.

Disinhibition enables vocal repertoire expansion after a critical period

The efficiency of motor skill acquisition is age-dependent, making it increasingly challenging to learn complex manoeuvres later in life. Zebra finches, for instance, acquire a complex vocal motor programme during a developmental critical period after which the learned song is essentially impervious to modification. Although inhibitory interneurons are implicated in critical period closure, it is unclear whether manipulating them can reopen heightened motor plasticity windows. Using pharmacology and a cell-type specific optogenetic approach, we manipulated inhibitory neuron activity in a premotor area of adult zebra finches beyond their critical period. When exposed to auditory stimulation in the form of novel songs, manipulated birds added new vocal syllables to their stable song sequence. By lifting inhibition in a premotor area during sensory experience, we reintroduced vocal plasticity, promoting an expansion of the syllable repertoire without compromising pre-existing song production. Our findings provide insights into motor skill learning capacities, offer potential for motor recovery after injury, and suggest avenues for treating neurodevelopmental disorders involving inhibitory dysfunctions.

Properties of layer V pyramidal neurons in the primary motor cortex that represent acquired motor skills

Layer V neurons in primary motor cortex (M1) are required for motor skill learning. We analyzed training-induced plasticity using a whole-cell slice patch-clamp technique with a rotor rod task, and found that training induces diverse changes in intrinsic properties and synaptic plasticity in M1 layer V neurons. Although the causal relationship between specific cellular changes and motor performance is unclear, by linking individual motor performance to cellular/synaptic functions, we identified several cellular and synaptic parameters that represent acquired motor skills. With respect to cellular properties, motor performance was positively correlated with resting membrane potential and fast afterhyperpolarization, but not with the membrane resistance, capacitance, or threshold. With respect to synaptic function, the performance was positively correlated with AMPA receptor-mediated postsynaptic currents, but not with GABAA receptor-mediated postsynaptic currents. With respect to live imaging analysis in Thy1-YFP mice, we further demonstrated a cross-correlation between motor performance, spine head volume, and self-entropy per spine. In the present study, we identified several changes in M1 layer V pyramidal neurons after motor training that represent acquired motor skills. Furthermore, training increased extracellular acetylcholine levels known to promote synaptic plasticity, which is correlated with individual motor performance. These results suggest that systematic control of specific intracellular parameters and enhancement of synaptic plasticity in M1 layer V neurons may be useful for improving motor skills.

Comparing Real and Imitative Practice with No Practice during Observational Learning of Hand Motor Skills from Animations

In two experiments, we compared the effects of practice (real and imitative) with no practice on the observational learning of hand motor skills from animated videos. Experiment 1 investigated learning to play a series of piano clips of varying complexity. Results demonstrated improved learning efficiency with imitative practice compared to no practice. Experiment 2 featured a paper-folding task, and results indicated that real practice led to significantly greater learning than no practice. Furthermore, a significant interaction was found with gender and practice, where females learned best with both real and imitative practice, but males did not benefit from these interventions. However, males outperformed females in the no practice condition. Overall, we found benefits of practice versus no practice for both tasks. However, the most effective type of practice was dependent upon the task: imitative practice for piano playing, and real practice for paper folding. Task complexity and gender were also found to be moderating factors.

The effectiveness of different attentional foci on the acquisition of sport-specific motor skills in healthy adults: a systematic review with network meta-analysis.

The acquisition of motor skills is a key element in many sports. A motor learning principle, which is frequently used to support skill acquisition is the application of different attentional foci. The effectiveness of different attentional foci on performance and the learning of motor skills has been investigated in various sports using randomised controlled trials. The aim of the present study was to investigate the effectiveness of different attentional foci (such as external (EFA) and internal attentional foci (IFA), but also holistic and switching foci) on the performance and learning of a sport-specific motor task in healthy individuals. This study was a systematic review with network meta-analysis. We followed the Prisma reporting guideline and the Cochrane handbook for systematic reviews. Cinahl, Embase, Medline and Cochrane Central were searched for eligible studies. Network meta-analyses were performed for the post-acquisition, retention and transfer test endpoints. Twelve studies were included in the review. At post-acquisition an EFA was the most effective intervention compared to the control intervention (SMD: 0.9855; 95% CI [0.4-1.57]; p: 0.001). At the retention and transfer test endpoints, a holistic focus of attention had the highest effectiveness compared to an IFA (SMD 0.75; 95% CI [-0.1 to 1.6]; p: 0.09) and (SMD 1.16; 95% CI [0.47-1.86]; p: 0.001). For all three endpoints, we analysed a greater effectiveness of an EFA and holistic focus compared to an IFA. Several promising different attentional focus interventions were identified. The largest effects were analysed for a holistic focus. However, only one study used this intervention and therefore there remains uncertainty about the effectiveness. With regard to the inconsistency observed, the analysis at post-acquisition should be interpreted with caution. Modified versions of the EFA were the imagined and the dynamic EFA. Both were only explored in single studies and should therefore be investigated in further follow-up studies that directly compare them.

Temporal dynamics of white and gray matter plasticity during motor skill acquisition: a comparative diffusion tensor imaging and multiparametric mapping analysis.

Learning new motor skills relies on neural plasticity within motor and limbic systems. This study uniquely combined diffusion tensor imaging and multiparametric mapping MRI to detail these neuroplasticity processes. We recruited 18 healthy male participants who underwent 960min of training on a computer-based motion game, while 14 were scanned without training. Diffusion tensor imaging, which quantifies tissue microstructure by measuring the capacity for, and directionality of, water diffusion, revealed mostly linear changes in white matter across the corticospinal-cerebellar-thalamo-hippocampal circuit. These changes related to performance and reflected different responses to upper- and lower-limb training in brain areas with known somatotopic representations. Conversely, quantitative MRI metrics, sensitive to myelination and iron content, demonstrated mostly quadratic changes in gray matter related to performance and reflecting somatotopic representations within the same brain areas. Furthermore, while myelin and iron-sensitive multiparametric mapping MRI was able to describe time lags between different cortical brain systems, diffusion tensor imaging detected time lags within the white matter of the motor systems. These findings suggest that motor skill learning involves distinct phases of white and gray matter plasticity across the sensorimotor network, with the unique combination of diffusion tensor imaging and multiparametric mapping MRI providing complementary insights into the underlying neuroplastic responses.

Motor learning alters vision, but vision does not alter motor learning.

During visuomotor learning, improvements in motor performance accompany changes in how people use vision. However, the dependencies between altered visual reliance and improvements in motor skill is unclear. The present studies used an online sequence learning task to quantify how changing the availability of visual information affected motor skill learning (study 1) and how changing motor skill affected visual reliance (study 2). Participants used their keyboard to respond to targets falling vertically down a game screen. In study 1 (n = 49), the availability of visual information was altered by manipulating where the targets were visible on the screen. Three experimental groups practiced the task during full or limited vision conditions (when the targets were only visible in specific areas). We hypothesized that limiting visual information would reduce motor learning (i.e., the rate of improvement during training trial blocks). Instead, although participants performed worse during limited vision trials (P < 0.001), there was no difference in learning rate (P = 0.87). In study 2 (n = 119), all participants practiced the task with full vision and their visual reliance (i.e., their performance change between full and limited vision conditions) was quantified before and after training. We hypothesized that with motor learning, visual reliance on future targets would increase, whereas visual reliance on the current targets would decrease. The results of study 2 partially support our hypotheses with visual reliance decreasing for all visual areas (P < 0.001). Together, the results suggest changing motor skill alters how people use vision, but changing visual availability does not affect motor learning.NEW & NOTEWORTHY Previous research has established how people use visual information changes with motor learning. However, the dependencies of these two processes on each other are unclear. We find that limiting the availability of visual information degrades motor performance but not motor learning. We also find that motor learning reduces the impact of limiting the availability of visual information on motor performance. Together, these results suggest that how people use visual information depends on their motor skill.

Learning-to-learn as a metacognitive correlate of functional outcomes after stroke: a cohort study.

Meta-learning is a metacognitive function for successful, efficient learning in various tasks. While it is possible that meta-learning is linked to functional recovery in stroke, it has not been investigated in previous clinical research on metacognition. Examine if individual meta-learning ability is associated with functional outcomes. Cohort study. Rehabilitation ward in Fujita Health University Hospital. Twenty-nine hemiparetic people after stroke. The study measured individual sensorimotor adaptation rate, meta-learning (acceleration of adaptation through training), and Functional Independence Measure (FIM) motor effectiveness, an index of functional outcome measuring improvement in proficiency of activity of daily living (ADL). Participants performed visuomotor adaptation training sessions with their less-affected arm. They made arm-reaching movements to hit a target with cursor feedback, which was occasionally rotated with regard to their hand positions, requiring them to change the movement direction accordingly. Initial adaptation rate and meta-learning were quantified from pre- and post-training tests. The relationship between these indices of adaptation ability and FIM motor effectiveness was examined by multiple linear regression analyses. One participant was excluded before data collection in the motor task. In the remaining 28 individuals, the regression analyses revealed that FIM motor effectiveness positively correlated with meta-learning (µ=0.90, P=0.008), which was attenuated by age (µ=-0.015, P=0.005), but not with initial adaptation rate (P=0.08). Control analyses suggested that this observed association between FIM motor effectiveness and meta-learning was not mediated by patients' demographics or stroke characteristics. This study demonstrates that those who can accelerate adaptation through training are likely to improve ADL, suggesting that meta-learning may be linked with functional outcomes in some stroke individuals. Meta-learning may enable the brain to keep (re-)learning motor skills when motor functions change abruptly due to stroke and neural recovery, thereby associated with improvement in ADL. Meta-learning is part of metacognitive functions that is positively associated with functional outcomes.

Sleep consolidation potentiates sensorimotor adaptation.

Contrary to its well-established role in declarative learning, the impact of sleep on motor memory consolidation remains a subject of debate. Current literature suggests that while motor skill learning benefits from sleep, consolidation of sensorimotor adaptation (SMA) depends solely on the passage of time. This has led to the proposal that SMA may be an exception to other types of memories. Here, we addressed this ongoing controversy in humans through three comprehensive experiments using the visuomotor adaptation paradigm (N=290, 150 females). In Experiment 1, we investigated the impact of sleep on memory retention when the temporal gap between training and sleep was not controlled. In line with the previous literature, we found that memory consolidates with the passage of time. In Experiment 2, we used an anterograde interference protocol to determine the time window during which SMA memory is most fragile and, thus, potentially most sensitive to sleep intervention. Our results show that memory is most vulnerable during the initial hour post-training. Building on this insight, in Experiment 3 we investigated the impact of sleep when it coincided with the critical first hour of memory stabilization. This manipulation unveiled a benefit of sleep (30% memory enhancement) alongside an increase in spindle density and spindle-SO coupling during NREM sleep, two well-established neural markers of sleep consolidation. Our findings reconcile seemingly conflicting perspectives on the active role of sleep in motor learning and point to common mechanisms at the basis of memory formation.Significance statement While there is compelling evidence that sleep improves declarative memory, its role in the consolidation of motor memories remains a long-standing debate. For example, it is currently established that sensorimotor adaptation (SMA) consolidates with the passage of time, irrespective of sleep. This has led to the proposal that SMA may be an exception to other types of memories. Our findings indicate that SMA memories may indeed consolidate with both the passage of time and sleep, depending on the proximity between training and bedtime. Our work sheds light on this controversy and points to the existence of common mechanisms supporting consolidation across memory domains. Furthermore, it may impact rehabilitation programs, expediting motor injury recovery by aligning training sessions with sleep.