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Context: The best current evidence supports the effectiveness of neuromuscular training in reducing the risk of injury; however, the rate of anterior cruciate ligament (ACL) injuries is still high. Neurocognitive training (NT) has successfully improved biomechanical risk factors, but they have been considered in only a few studies. Objective: To review the literature to determine the effect of NT on biomechanical risk factors related to ACL injury in athletes. Evidence Acquisition: We searched PubMed, Google Scholar, Scopus, Science Direct, and the Physiotherapy Evidence Database from inception to August 2011. We included randomized controlled trials that used motor learning approaches and injury prevention programs to investigate kinematic and kinetic risk factors related to ACL injury. The quality of each clinical trial study was evaluated by the Physiotherapy Evidence Database scale. The eligibility criteria were checked based on the PICOS (population, intervention, comparison, outcome, and study type) framework. Evidence Synthesis: A total of 9 studies were included in the final analysis. Motor learning approaches include internal and external focus of attention, dual tasks, visual motor training, self-control feedback, differential learning, and linear and nonlinear pedagogy, combined with exercise programs. In most of the studies that used NT, a significant decrease in knee valgus; tibial abduction and external rotation; ground reaction force; and an increase in knee-, trunk-, hip-, and knee-flexion moment was observed. Conclusion: In classical NT, deviation from the ideal movement pattern especially emphasizing variability and self-discovery processes is functional in injury prevention and may mitigate biomechanical risk factors of ACL injuries in athletes. Practitioners are advised to use sport-specific cognitive tasks in combination with neuromuscular training to simulate loads of the competitive environment. This may improve ACL injury risk reduction and rehabilitation programs. [ABSTRACT FROM AUTHOR]

The purpose of this study is to analyze in depth the relevance of Vygotsky's constructivism learning theory in differentiated learning in elementary schools. Differentiated learning is an effort to adapt the learning process in the classroom to meet the learning needs of each individual. This adjustment is made by considering the interests, learning profiles, and readiness of students to improve learning outcomes. With this adjustment, students can learn according to their respective abilities and find understanding from their own experiences. On the other hand, constructivist learning theory states that learning is a process in which students can build their knowledge. One of the constructivists learning theories was proposed by Vygotsky, known as social constructivism. Vygotsky's constructivism emphasizes the interaction of interpersonal (social), cultural-historical, and individual factors as the key to human development. The constructivist theory has relevance to differentiated learning in terms of meaningful learning and student activity. Differentiated learning applies constructivist theory in learning by considering the individual characteristics of students. In addition, the concept of the zone of proximal development (ZPD) and scaffolding are highly relevant in differentiated learning that accommodates the full potential of students and considers the individual abilities of students. [ABSTRACT FROM AUTHOR]

The paradoxical effects of contextual interference (CI) assume that high CI practices hinder performances during the acquisition phase of learning, while providing more permanent enhancement during the retention phase. This meta-analysis evaluates the possible generalizability of the CI phenomenon in physical education (PE) and sports contexts, with regard to the acute and relatively permanent gains in performance outcomes. A total of 933 records from five electronic databases were screened using the PICOS criteria, of which 36 studies were selected. Outcomes evaluating the performance changes (Δ) from pre-post, post-retention, and pre-retention tests were included. Out of 183 overall pooled outcomes, Δ in only 37 performance outcomes (20%) agreed with the paradoxical CI effects on the acquisition or the relatively permanent gains. No statistically significant overall difference was detected for “Δ pre-post” between low (blocked) (28.9 ± 59.5%) and high (random/serial) (27.9 ± 52.8%) CI (effect size (ES) = 0.1, p = 0.35). An overall significant difference (p = 0.001) in favor of high CI practice was detected in “Δ post-retention.” However, this difference was not large enough (ES = − 0.35) to produce an overall greater long-term gain following high (24.56 ± 4.4%), compared to low (21.9 ± 9.8%) CI (ES = − 0.13, p = 0.18). Out of 10 tested variables, only the age significantly moderated both CI effects (p < 0.0001 for both Δ pre-post and Δ pre-retention) and the female proportion significantly moderated only the first CI effect (p = 0.009 for Δ pre-post). These findings found very limited evidence supporting the recommendation to employ high CI practices to gain a longer-term performance advantage, calling into question the generalization of the CI model to PE and sports practices. High-quality follow-up research evaluating alternative motor-learning models are therefore needed. [ABSTRACT FROM AUTHOR]

In this investigation, we examined the influence of two approaches of motor skill learning (differential learning and repetition-based) for an explosive motor skill. Twenty-seven individuals completed four training sessions of a standing broad jump task, presented with either differential training or a repetition-based approach. We collected pre-and post-training assessments that included maximal jump distances used to index performance and the recording of ground reaction forces to determine potential biomechanical changes (normalized vertical ground reaction force – GRFvert, rate of force development – RFD, and horizontal take-off velocity - Vhor). Results showed that differential training exhibited greater jump distances than repetition-based training (p <.001) but no training effect was found for jump distances between pre- and post-assessments for either training approach (p =.15). However, a significant increase occurred for Vhor with greater velocities achieved following training (p =.03). Overall, differential training failed to show the expected performance enhancements for a discrete, explosive motor task; this may be related to limited exposure and task specific demands of the movement. Further research is needed to better understand the task factors influencing skill acquisition from differential training. [ABSTRACT FROM AUTHOR]

Effective sports training should be attuned to the athlete's specific conditionings and characteristics. In motor learning research, two often neglected factors that influence this resonance are the learner's athletic background and the structural diversity of exercises (e.g., relative similarity). In the setting of real-word training with higher external validity, this study examines the effects of three learning approaches (i.e., contextual interference (CI), differential learning (DL), and free-play control condition (CO)) on the parallel learning of handball (HB), volleyball (VB), and basketball (BB) skills, considering participants' prior sport backgrounds. Forty-five males (15 HB, 15 VB, and 15 BB players) with a mean age of 22 ± 1.4 years and at least 6 years of experience in the mastered discipline voluntarily participated in this study. A pre–post–retention test design including a 6-week-intervention program was employed. During the intervention period, participants engaged in three training sessions a week, with each one lasting approximately 80 min. Each of the three test sessions involved the execution of ten attempts of BB free-throw shooting, HB three-step goal throwing, and VB underarm passing following a blocked order. In terms of short-term (pre–post) gain, only the DL group significantly improved their performance in both non-mastered disciplines (p = 0.03, ES = 1.58 for the BB free-throw and p = 0.05, ES = 0.9 for the HB shooting tests), with a trend (ES = 0.53) towards an improvement in the performance of the mastered VB underarm-pass skill. In terms of relatively permanent gains, the CI group significantly improved their performances from pre- to retention test only in the non-mastered BB free-throw skill (p = 0.018, ES = 1.17). In contrast, the DL group significantly improved their performance at retention compared to the pre-test in both non-mastered BB (p = 0.004, ES = 1.65) and HB (p = 0.003, ES = 2.15) skills, with a trend (ES = 0.4) towards improvement in the mastered VB test. In both the short-term and relatively long-term, higher composite score gains were observed in DL compared to CI (p = 0.006, ES = 1.11 and 0.049, ES = 1.01) and CO (p = 0.001, ES = 1.73 and <0.0001, ES = 2.67). In conclusion, the present findings provide additional support for the potential advantages of the DL model over those of CI. These findings can serve as the basis for tailored training and intervention strategies and provide a new perspective for addressing various issues related to individual and situational learning. [ABSTRACT FROM AUTHOR]

Equations are often used in mathematics and other subjects, which means that a media can teach students how to solve equations, particularly linear equations of two variables, or Sistem Persamaan Linear Dua Variabel (SPLDV) as it is called in Indonesian, is needed. However, most teachers are still focused on developing the learning process and teaching materials rather than developing an application technology-based learning media. As we know that technology-based learning is currently the focus of teaching and learning activities in the digital era, especially learning after the pandemic. This study aimed to develop an application that can be a reference for teaching media in learning activities to improve students’ mathematical understanding and ability. The developed application is named, Integrated and Convenient Android-based Simulation or Simulasi Android Terpadu dan Nyaman, abbreviated as SANTUY. This development study with Analysis, Design, Development, Implementation, and Evaluation (ADDIE) model, explained in detail in the paper, took seventy-five subjects consisting of six expert validators, nine users, and sixty students. The expert validators comprised three media experts and three material experts. The evaluation stage involved students from two groups, each consisting of thirty students. The results showed that the average percentage of the feasibility of the SANTUY SPLDV solution simulation-assisted application with differential learning nuance was 79.62%, which means the application is adequate. The level of usefulness of the SANTUY SPLDV solution simulation-assisted application with differential learning nuance was 86.11%, which is categorized as “excellent”. In addition, using the SANTUY SPLDV application had a direct positive influence on improving students’ mathematical understanding and ability.

How the process of acquiring and learning new motor skills can be enhanced is one of the basic questions in theoretical and applied movement science, rehabilitation and sport. The Differential Learning (DL) approach is mainly characterized by taking advantage, for the purpose of learning, of fluctuations that occur, without movement repetitions and without corrections during the skill acquisition process. The purpose of this study was to examine the effects of Differential Learning (DL) and Contextual Interference (CI) on the Retention and Transfer of Badminton backhand short serve. Prior to the implementation of the protocol, all participants of the pre - test were taken. Then, each group of research performed for 8 sessions according to the type of training. One day after the completion of the practice protocol, of all participants were taken the tests of Retention and Transfer. The analysis t -test indicated that there was a significant difference between the groups DL and CI in tests Retention and Transfer (p= 0.00). In fact, the results of the research show the effectiveness of the DL approach on the Retention and Transfer of Badminton backhand short serve. Based on the results of the research, the conclusion is that the DL approach is useful for learning skills, and can discover adaptive solutions by creating oscillations in the individual and helped to improve and learning skills. [ABSTRACT FROM AUTHOR]

Variation during practice is widely accepted to be advantageous for motor learning and is, therefore, a valuable strategy to effectively reduce high-risk landing mechanics and prevent primary anterior cruciate ligament (ACL) injury. Few attempts have examined the specific effects of variable training in athletes who have undergone ACL reconstruction. Thereby, it is still unclear to what extent the variations in different sensor areas lead to different effects. Accordingly, we compared the effects of versatile movement variations (DL) with variations of movements with emphasis on disrupting visual information (VMT) in athletes who had undergone ACL reconstruction. Forty-five interceptive sports athletes after ACL reconstruction were randomly allocated to a DL group (n = 15), VT group (n = 15), or control group (n = 15). The primary outcome was functional performance (Triple Hop Test). The secondary outcomes included dynamic balance (Star Excursion Balance Test (SEBT)), biomechanics during single-leg drop-landing task hip flexion (HF), knee flexion (KF), ankle dorsiflexion (AD), knee valgus (KV), and vertical ground reaction force (VGRF), and kinesiophobia (Tampa Scale of Kinesiophobia (TSK)) assessed before and after the 8 weeks of interventions. Data were analyzed by means of 3 × 2 repeated measures ANOVA followed by post hoc comparison (Bonferroni) at the significance level of p ≤ 0.05. Significant group × time interaction effects, main effect of time, and main effect of group were found for the triple hop test and all eight directions, SEBT, HF, KF, AD, KV, VGRF, and TSK. There was no significant main effect of group in the HF and triple hop test. Additionally, significant differences in the triple hop test and the seven directions of SEBT, HF, KF, KV, VGRF, and TSK were found between the control group and the DL and VMT groups. Between group differences in AD and the medial direction of SEBT were not significant. Additionally, there were no significant differences between VMT and the control group in the triple hop test and HF variables. Both motor learning (DL and VMT) programs improved outcomes in patients after ACL reconstruction. The findings suggest that DL and VMT training programs lead to comparable improvements in rehabilitation. [ABSTRACT FROM AUTHOR]

Predictions of photovoltaic (PV) energy supply, based on data statistics of weather and PV records, are required in short‐intra and day‐ahead planning of PV plant operations. Numerical weather prediction (NWP), based on physical consideration, can simulate the progress of local cloudiness, although their prognoses are usually delayed by a few hours and are not provided with the quality desired by PV operators. Differential polynomial neural network (D‐PNN) is an unconventional hybrid regression technique, based on a novel learning strategy and able to resolve some problems in modeling patterns in high‐dynamical and chaotic non‐deterministic systems. D‐PNN splits the general partial differential equation (PDE) of the kth order into a summation form of two‐variable PDEs of a predetermined low order. PDE derivatives are transformed and separated into the Laplace counterparts, from which the unknown node originals are restored using the inverse L‐operation. D‐PNN searches for the best 2‐input couples, inserting node by node into its changeable tree structure, to expand the modular sum model by usable PDE components. The PDE‐modularization enhances the D‐PNN capability in modeling high uncertainty in weather patterns in the ground‐layer atmosphere, analogous to NWP. The designed PV intra‐ and day‐ahead prediction schemes, using hourly increasing and fixed‐time prediction horizons, were compared with different computing approaches based on differential, probabilistic and statistical learning. Machine learning (ML) models calculate the output PV power in each single hour separately or in an all‐day processing series with trained input delay. The results are analyzed and interpreted for each day and prediction hour. The quantitative results for both prediction procedures are comparable, showing the average intraday 11.6% and all‐day 9.6% (or rather 12.3% respectively) inaccuracy with respect to the daily peak power. Training data samples with spatial overlap in the regional scope and ML initialized similarity intervals are related to the fixed‐day or hourly increased input–output delay. This approach can compensate for unpredictable midterm variances in local weather patterns (caused by terrain or convection anomalies) and possible errors in model initialization. PV power was converted to and restored from the clear sky index in the modeling input/output, which represents its relative values, disregarding the actual solar cycle time. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Sport & Health Research is the property of Journal of Sport & Health Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Effective sports training should be attuned to the athlete’s specific conditionings and characteristics. In motor learning research, two often neglected factors that influence this resonance are the learner’s athletic background and the structural diversity of exercises (e.g., relative similarity). In the setting of real-word training with higher external validity, this study examines the effects of three learning approaches (i.e., contextual interference (CI), differential learning (DL), and free-play control condition (CO)) on the parallel learning of handball (HB), volleyball (VB), and basketball (BB) skills, considering participants’ prior sport backgrounds. Forty-five males (15 HB, 15 VB, and 15 BB players) with a mean age of 22 ± 1.4 years and at least 6 years of experience in the mastered discipline voluntarily participated in this study. A pre–post–retention test design including a 6-week-intervention program was employed. During the intervention period, participants engaged in three training sessions a week, with each one lasting approximately 80 min. Each of the three test sessions involved the execution of ten attempts of BB free-throw shooting, HB three-step goal throwing, and VB underarm passing following a blocked order. In terms of short-term (pre–post) gain, only the DL group significantly improved their performance in both non-mastered disciplines (p = 0.03, ES = 1.58 for the BB free-throw and p = 0.05, ES = 0.9 for the HB shooting tests), with a trend (ES = 0.53) towards an improvement in the performance of the mastered VB underarm-pass skill. In terms of relatively permanent gains, the CI group significantly improved their performances from pre- to retention test only in the non-mastered BB free-throw skill (p = 0.018, ES = 1.17). In contrast, the DL group significantly improved their performance at retention compared to the pre-test in both non-mastered BB (p = 0.004, ES = 1.65) and HB (p = 0.003, ES = 2.15) skills, with a trend (ES = 0.4) towards improvement in the mastered VB test. In both the short-term and relatively long-term, higher composite score gains were observed in DL compared to CI (p = 0.006, ES = 1.11 and 0.049, ES = 1.01) and CO (p = 0.001, ES = 1.73 and

Abstract Background Lack of the neuromuscular control during locomotion in the knee joint leads to an increased risk of anterior cruciate ligament (ACL) injury in children. Hence, we aimed to explore the effects of a repetitive, model-oriented, and self-organized approach on lower limb kinematics during gait in children. Methods In randomized controlled trial, 36 children with 4 ± 0.79 years of age from the children gym were randomly (a lottery method) allocated into three groups, including (1) the model-oriented (n = 10), (2) Differential Learning (n = 11), and (3) control (n = 10) groups. Kinematic data of hip, knee, and ankle joints in the sagittal plane were recorded by a GoPro camera at the moments of heel-ground contact and toe-off the ground before and after a 6-week intervention (two sessions per week). Results The results indicate a 35% post-intervention increase of ankle dorsiflexion (95% CI: − 5.63 _ − 0.96) in the moment of heel-ground contact in the model-oriented group; however, knee flexion (95% CI: − 1.05 _ 8.34) and hip flexion (95% CI: 3.01 _ 11.78) were respectively decreased by 20% and 20%. After the intervention, moreover, ankle plantar flexion (95% CI: − 9.18 _ − 2.81) and hip extension (95% CI: − 12.87 _ − 3.72) have respectively increased by 37% and 37%, while knee flexion (95% CI: 3.49 _ 11.30) showed a %16 decrease in the moment of toe off the ground. As for the Differential Learning group, ankle dorsiflexion (95% CI: − 5.19 _ − 1.52) increased by 33%, and knee (95% CI: 0.60 _ 5.76) and hip flexion (95% CI: 2.15 _ 7.85) respectively decreased by 17% and 17% at the moment of the heel-ground contact following the intervention. At toe lifting off the ground, the plantar flexion (95% CI: − 7.77 _ − 2.77) increased by 35%, knee flexion (95% CI: 2.17 _ 7.27) decreased to 14%, and hip extension (95% CI: − 9.98 _ − 4.20) increased by %35 following the intervention for the Differential Learning group subjects. Based on the results obtained from the one-way ANOVA, there was a significant difference between these groups and the control group in all kinematic gait variables (p ≤ 0.05). However, no statistically significant differences were found between the two experimental groups. Conclusions The results implied that the model-oriented repetitive and the self-organized Differential Learning approach were both appropriate to alter the kinematic gait pattern in the 3–5-year-old children. Previous research has almost exclusively recommended a model-oriented approach to change kinematic patterns and preventing non-contact motor injuries. However, the present study showed that the Differential Learning approach can help children to achieve the same goal by continuously changing environments and stimulating challenges. Trial registration: Current Controlled Trials using the IRCT website with ID number of, IRCT20130109012078N5 “Prospectively registered” at 14/5/2021.

Random practice is a form of differential learning and its favorable acute effects on motor performance are well described when visual tasks are practiced. However, no study to date has investigated the acute effects of differential learning using variable proprioceptive stimuli instead of the visual cues. The aim of the present study was to compare the acute effects of randomized versus blocked lower-extremity proprioceptive training stimuli on balance and postural adjustments. In two conditions, healthy young males (n = 15, age = 23 years) performed 16 one-legged landings on a board tilted in four directions: 1) tilt direction unknown and randomized and 2) tilt direction known with order of presentation blocked. Multi-segmental angular sway while balancing on an unstable surface and postural responses to perturbation stimulus by surface tilts were measured before and 4 min after training. Overall frontal-plane postural sway on the unstable surface decreased (p < 0.05, η2 = 0.022) in both conditions, while sagittal-plane postural sway remained unchanged. When the surface was toes-up tilted in the perturbation test, the sagittal-plane shank-thigh-pelvis alignment improved in both conditions (p < 0.05, η2 = 0.017), but the direction of the segmental positioning was non-uniform across participants. We conclude that randomization vs. blocking of units of lower-extremity proprioceptive training did not affect balance and postural control in our cohort of healthy young adults but the improvements were test-specific. [ABSTRACT FROM AUTHOR]

Random practice is a form of differential learning and its favorable acute effects on motor performance are well described when visual tasks are practiced. However, no study to date has investigated the acute effects of differential learning using variable proprioceptive stimuli instead of the visual cues. The aim of the present study was to compare the acute effects of randomized versus blocked lower-extremity proprioceptive training stimuli on balance and postural adjustments. In two conditions, healthy young males (n = 15, age = 23 years) performed 16 one-legged landings on a board tilted in four directions: 1) tilt direction unknown and randomized and 2) tilt direction known with order of presentation blocked. Multi-segmental angular sway while balancing on an unstable surface and postural responses to perturbation stimulus by surface tilts were measured before and 4 min after training. Overall frontal-plane postural sway on the unstable surface decreased (p < 0.05, η2 = 0.022) in both conditions, while sagittal-plane postural sway remained unchanged. When the surface was toes-up tilted in the perturbation test, the sagittal-plane shank-thigh-pelvis alignment improved in both conditions (p < 0.05, η2 = 0.017), but the direction of the segmental positioning was non-uniform across participants. We conclude that randomization vs. blocking of units of lower-extremity proprioceptive training did not affect balance and postural control in our cohort of healthy young adults but the improvements were test-specific.

Copyright of Journal of Sport Psychology (2676-3729) is the property of Shahid Beheshti University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In search of more detailed explanations for body-mind interactions in physical activity, neural and physiological effects, especially regarding more strenuous sports activities, increasingly attract interest. Little is known about the underlying manifold (neuro-)physiological impacts induced by different motor learning approaches. The various influences on brain or cardiac function are usually studied separately and modeled linearly. Limitations of these models have recently led to a rapidly growing application of nonlinear models. This study aimed to investigate the acute effects of various sequences of rope skipping on irregularity of the electrocardiography (ECG) and electroencephalography (EEG) signals as well as their interaction and whether these depend on different levels of active movement noise, within the framework of differential learning theory. Thirty-two males were randomly and equally distributed to one of four rope skipping conditions with similar cardiovascular but varying coordinative demand. ECG and EEG were measured simultaneously at rest before and immediately after rope skipping for 25 mins. Signal irregularity of ECG and EEG was calculated via the multiscale fuzzy measure entropy (MSFME). Statistically significant ECG and EEG brain area specific changes in MSFME were found with different pace of occurrence depending on the level of active movement noise of the particular rope skipping condition. Interaction analysis of ECG and EEG MSFME specifically revealed an involvement of the frontal, central, and parietal lobe in the interplay with the heart. In addition, the number of interaction effects indicated an inverted U-shaped trend presenting the interaction level of ECG and EEG MSFME dependent on the level of active movement noise. In summary, conducting rope skipping with varying degrees of movement variation appears to affect the irregularity of cardiac and brain signals and their interaction during the recovery phase differently. These findings provide enough incentives to foster further constructive nonlinear research in exercise-recovery relationship and to reconsider the philosophy of classical endurance training. [ABSTRACT FROM AUTHOR]

Background: Lack of the neuromuscular control during locomotion in the knee joint leads to an increased risk of anterior cruciate ligament (ACL) injury in children. Hence, we aimed to explore the effects of a repetitive, model-oriented, and self-organized approach on lower limb kinematics during gait in children. Methods: In randomized controlled trial, 36 children with 4 ± 0.79 years of age from the children gym were randomly (a lottery method) allocated into three groups, including (1) the model-oriented (n = 10), (2) Differential Learning (n = 11), and (3) control (n = 10) groups. Kinematic data of hip, knee, and ankle joints in the sagittal plane were recorded by a GoPro camera at the moments of heel-ground contact and toe-off the ground before and after a 6-week intervention (two sessions per week). Results: The results indicate a 35% post-intervention increase of ankle dorsiflexion (95% CI: − 5.63 _ − 0.96) in the moment of heel-ground contact in the model-oriented group; however, knee flexion (95% CI: − 1.05 _ 8.34) and hip flexion (95% CI: 3.01 _ 11.78) were respectively decreased by 20% and 20%. After the intervention, moreover, ankle plantar flexion (95% CI: − 9.18 _ − 2.81) and hip extension (95% CI: − 12.87 _ − 3.72) have respectively increased by 37% and 37%, while knee flexion (95% CI: 3.49 _ 11.30) showed a %16 decrease in the moment of toe off the ground. As for the Differential Learning group, ankle dorsiflexion (95% CI: − 5.19 _ − 1.52) increased by 33%, and knee (95% CI: 0.60 _ 5.76) and hip flexion (95% CI: 2.15 _ 7.85) respectively decreased by 17% and 17% at the moment of the heel-ground contact following the intervention. At toe lifting off the ground, the plantar flexion (95% CI: − 7.77 _ − 2.77) increased by 35%, knee flexion (95% CI: 2.17 _ 7.27) decreased to 14%, and hip extension (95% CI: − 9.98 _ − 4.20) increased by %35 following the intervention for the Differential Learning group subjects. Based on the results obtained from the one-way ANOVA, there was a significant difference between these groups and the control group in all kinematic gait variables (p ≤ 0.05). However, no statistically significant differences were found between the two experimental groups. Conclusions: The results implied that the model-oriented repetitive and the self-organized Differential Learning approach were both appropriate to alter the kinematic gait pattern in the 3–5-year-old children. Previous research has almost exclusively recommended a model-oriented approach to change kinematic patterns and preventing non-contact motor injuries. However, the present study showed that the Differential Learning approach can help children to achieve the same goal by continuously changing environments and stimulating challenges. Trial registration: Current Controlled Trials using the IRCT website with ID number of, IRCT20130109012078N5 "Prospectively registered" at 14/5/2021. [ABSTRACT FROM AUTHOR]

Various motor learning approaches, such as Schema Theory, Contextual Interference or Differential Learning, have proposed that varying the task during skill acquisition prompts superior learning. However, past research has mainly compared task variation in an experimental group to no task variation in a control group. Past research has more rarely compared specific intervention groups and/or addressed how varying amounts of task variation may affect skill learning. Our aim in this study was to compare motor learning of golf putting across four groups of novice golfers randomly assigned to these conditions: (a) a contextual interference group who putted at varied putting distances and had varied repetitive weekly schedule patterns, (b) a differential learning group who putted at multiple putting distances, putting amplitudes, and putting movements and had no repetitions, (c) an identical differential learning as in (b) except that participants also varied the putter, and (d) a control group who experienced no practice variations. Participants were 42 university students randomly divided into the four groups. All groups completed eight training sessions of 36 putts per session over four weeks, a pretest, posttest, two retention tests (one and three weeks after posttest) and transfer tasks (different floor). Average hit ratios and minimal distances to the hole were captured and analyzed by Scheirer-Ray-Hare test and Mann-Whitney post-hoc tests. Results showed improved hit ratios from pre- to post-test for all groups, and a stable retention performance for the variable training groups in contrast to the control group (p =.003). Transfer performance was low for all variable training groups with a significantly lower control group performance on transfer test 2 (p =.008). In conclusion, variable training schedules in all experimental groups benefited motor learning relative to controls, and differences in the amount of task variation between groups with variable training schedules did not affect skill acquisition. [ABSTRACT FROM AUTHOR]

Background: Differential learning (DL) is a motor learning method characterized by high amounts of variability during practice and is claimed to provide the learner with a higher learning rate than other methods. However, some controversy surrounds DL theory, and to date, no overview exists that compares the effects of DL to other motor learning methods.Objective: To evaluate the effectiveness of DL in comparison to other motor learning methods in the acquisition and retention phase.Design: Systematic review and exploratory meta-analysis.Methods: PubMed (MEDLINE), Web of Science, and Google Scholar were searched until February 3, 2020. To be included, (1) studies had to be experiments where the DL group was compared to a control group engaged in a different motor learning method (lack of practice was not eligible), (2) studies had to describe the effects on one or more measures of performance in a skill or movement task, and (3) the study report had to be published as a full paper in a journal or as a book chapter.Results: Twenty-seven studies encompassing 31 experiments were included. Overall heterogeneity for the acquisition phase (post-pre; I2 = 77%) as well as for the retention phase (retention-pre; I2 = 79%) was large, and risk of bias was high. The meta-analysis showed an overall small effect size of 0.26 [0.10, 0.42] in the acquisition phase for participants in the DL group compared to other motor learning methods. In the retention phase, an overall medium effect size of 0.61 [0.30, 0.91] was observed for participants in the DL group compared to other motor learning methods.Discussion/Conclusion: Given the large amount of heterogeneity, limited number of studies, low sample sizes, low statistical power, possible publication bias, and high risk of bias in general, inferences about the effectiveness of DL would be premature. Even though DL shows potential to result in greater average improvements between pre- and post/retention test compared to non-variability-based motor learning methods, more high-quality research is needed before issuing such a statement. For robust comparisons on the relative effectiveness of DL to different variability-based motor learning methods, scarce and inconclusive evidence was found.

Background: Differential learning (DL) is a motor learning method characterized by high amounts of variability during practice and is claimed to provide the learner with a higher learning rate than other methods. However, some controversy surrounds DL theory, and to date, no overview exists that compares the effects of DL to other motor learning methods. Objective: To evaluate the effectiveness of DL in comparison to other motor learning methods in the acquisition and retention phase. Design: Systematic review and exploratory meta-analysis. Methods: PubMed (MEDLINE), Web of Science, and Google Scholar were searched until February 3, 2020. To be included, (1) studies had to be experiments where the DL group was compared to a control group engaged in a different motor learning method (lack of practice was not eligible), (2) studies had to describe the effects on one or more measures of performance in a skill or movement task, and (3) the study report had to be published as a full paper in a journal or as a book chapter. Results: Twenty-seven studies encompassing 31 experiments were included. Overall heterogeneity for the acquisition phase (post-pre; I 2 = 77%) as well as for the retention phase (retention-pre; I 2 = 79%) was large, and risk of bias was high. The meta-analysis showed an overall small effect size of 0.26 [0.10, 0.42] in the acquisition phase for participants in the DL group compared to other motor learning methods. In the retention phase, an overall medium effect size of 0.61 [0.30, 0.91] was observed for participants in the DL group compared to other motor learning methods. Discussion/Conclusion: Given the large amount of heterogeneity, limited number of studies, low sample sizes, low statistical power, possible publication bias, and high risk of bias in general, inferences about the effectiveness of DL would be premature. Even though DL shows potential to result in greater average improvements between pre- and post/retention test compared to non-variability-based motor learning methods, more high-quality research is needed before issuing such a statement. For robust comparisons on the relative effectiveness of DL to different variability-based motor learning methods, scarce and inconclusive evidence was found. [ABSTRACT FROM AUTHOR]

In this experiment, we compared changes in visuomotor performance and motor control after a single session of differential learning (DL) and contextual interference (CI) in a reaching task to mimic goalkeeping. Subjects (nDL = nCI = 16) stood in front of a wall with six LED-light targets that flashed on in a random order and subjects had to move their hand in front of it as fast as possible in order to extinguish the target. After the pre-test subjects followed a DL or CI training session, followed immediately by a post-test, followed by one hour of rest and a retention test. Performance and motor control were measured respectively by visuomotor response time (VMRT) and an Index of Motor Abundance (IMA; reflecting the strength of movement synergies) calculated with Uncontrolled Manifold analysis. A mixed-effects Bayesian ANOVA model was used to evaluate differences in changes in both parameters between both training groups. Averaged over the six targets, the decrease in VMRT was stronger for DL than CI at the post-test (interference effect) but not at retention. The IMA was on average increased at post- and retention test in both groups, indicating stronger synergies between the degrees-of-freedom. While the ANOVA for IMA was not conclusive, the changes were likely not different between both learning methods. Thus, while an interference effect was found for CI but not DL in terms of performance on the task, no such effect was observed on the behavioural level in terms of the strength of movement synergies. [ABSTRACT FROM AUTHOR]

• Several lightweight single gated RNNs are proposed with fewer parameters and better ability. • A differential weighted information storage mechanism (DWISM) is proposed. • A DL model for RUL prediction is constructed based on single gated RNNs and DWISM. • The superiority of the DL model is demonstrated based on actual gear tests and the C-MAPSS datasets. The full-life data of machine is complex and abundant, requiring specialized and deep predictive models for accurate forecasts. However, achieving high prediction accuracy often increases model complexity, hindering edge deployment. To address this, several lightweight regression operators named single gated recurrent neural networks have been first proposed, striking a balance between accuracy and simplicity, and exploring the contribution of different gates in RUL prediction. In addition, during the whole degeneration process of machines, there exists global tendency and local vibration, different trends should be learned differentially. Thus, a novel lightweight differential learning mechanism called differential weighted information storage mechanism is proposed, which adopts different weight updated rules to make the weights store different trend information without any parameters added. Based on the above improvement, several lightweight single gated recurrent neural networks with the differential weighted information storage mechanism are first proposed. Then, deep learning frameworks are constructed by the proposed operators and adopted in gears and aero-engines RUL prediction. The experiment results show the outperformance of the proposed methods in accuracy and computation burden compared with recent works. [ABSTRACT FROM AUTHOR]

Included among the components of current rehabilitation programs are combinations of exercise that aim to improve muscle strength and motor control. In many contexts, the patients must acquire, or re-acquire, motor skills so they can organize the motor responses necessary to limit the possibility of musculoskeletal damage. This article examines the principles of motor learning that can support clinical practice to improve patients' neuromuscular function. [ABSTRACT FROM AUTHOR]

Faced with the huge image data in the context of big data era, how to effectively manage, describe, and retrieve them has become a hotspot issue in academia and industry. In this paper, we propose an end-to-end image retrieval system based on deep convolutional neural network and differential learning method. Compared with the traditional method of using the deep convolutional activation features as the feature vector to match the image, we simplify the retrieval process of the method and decrease the problem of "semantic gap" in the content- based image retrieval system. We first build an image matching dataset based on the gravitational field model, that is to add the similarity score label for each image in the dataset manufacturing stage. Then we train the improved deep learning model and verify the effectiveness of the algorithm on three common image matching datasets (i.e., Caltech-101, Holidays, and Oxford Paris). Finally, the experimental results show that our improved deep learning model with differential learning method that used for image retrieval system has state-of-the-art image matching performance. The overall retrieval accuracy in Caltech-101, Holidays, and Oxford Paris datasets are 88.5%, 94.1%, and 96.2%, respectively. As the number of returned image increases, the retrieval accuracy of the system decreases slightly and eventually becomes stable at a high value. And the differential learning based retrieval method is superior to many traditional algorithms in terms of image matching accuracy and single image processing speed. [ABSTRACT FROM AUTHOR]

Unsupervised Domain adaptation (UDA) aims to transfer knowledge from the labeled source domain to the unlabeled target domain. Recently, to achieve reliable knowledge learning, progressively labeling (PL) is proposed to select reliable target samples for training. Although PL achieves fruitful results, there are two problems that limit its performance: (a) PL may neglect to filter out the uncertain samples that lie in the classification boundaries, which might select low-quality target samples for training, and lead to error accumulations; and (b) PL might overlook the consistent selection in the sample selection stage during iteration, which might result in unstable sample selection. To cope with these problems, we propose a novel method called Selected Confidence Sample Labeling (SCSL). SCSL consists of three parts: Discriminative Progressively Labeling (DPL), Consistency Strategy (CS), and Differential Learning (DL). First, DPL selects the high-confidence target samples with the maximum probability difference between the highest and the second-highest probabilities of classification. In this way, the uncertain samples are filtered out, while the qualities of the selected target samples are ensured. Second, CS includes a group of consistency strategies to make the selected high-confidence target samples near to the class-centroids. This further improves the confidence degree of the selected target samples, and ensures that the proposed model does not remove or replace the selected target samples during iteration. At last, DL is a bi-strategic training approach that applies CS and top- k fuzzy probability clustering to train the high-confidence and the remaining target samples, respectively. In doing so, all the target samples are trained simultaneously, and the generalization of the model is improved. Extensive experiments on four benchmark datasets with the comparison of several advanced algorithms demonstrate the superiority of SCSL. [ABSTRACT FROM AUTHOR]

A large body of research has shown superior learning rates in variable practice compared to repetitive practice. More specifically, this has been demonstrated in the contextual interference (CI) and in the differential learning (DL) approach that are both representatives of variable practice. Behavioral studies have indicate different learning processes in CI and DL. Aim of the present study was to examine immediate post-task effects on electroencephalographic (EEG) brain activation patterns after CI and DL protocols that reveal underlying neural processes at the early stage of motor consolidation. Additionally, we tested two DL protocols (gradual DL, chaotic DL) to examine the effect of different degrees of stochastic fluctuations within the DL approach with a low degree of fluctuations in gradual DL and a high degree of fluctuations in chaotic DL. Twenty-two subjects performed badminton serves according to three variable practice protocols (CI, gradual DL, chaotic DL), and a repetitive learning protocol in a within-subjects design. Spontaneous EEG activity was measured before, and immediately after each 20-min practice session from 19 electrodes. Results showed distinguishable neural processes after CI, DL, and repetitive learning. Increases in EEG theta and alpha power were obtained in somatosensory regions (electrodes P3, P7, Pz, P4, P8) in both DL conditions compared to CI, and repetitive learning. Increases in theta and alpha activity in motor areas (electrodes C3, Cz, C4) were found after chaotic DL compared to gradual DL, and CI. Anterior areas (electrodes F3, F7, Fz, F4, F8) showed increased activity in the beta and gamma bands after CI. Alpha activity was increased in occipital areas (electrodes O1, O2) after repetitive learning. Post-task EEG brain activation patterns suggest that DL stimulates the somatosensory and motor system, and engages more regions of the cortex than repetitive learning due to a tighter stimulation of the motor and somatosensory system during DL practice. CI seems to activate specifically executively controlled processing in anterior brain areas. We discuss the obtained patterns of post-training EEG traces as evidence for different underlying neural processes in CI, DL, and repetitive learning at the early stage of motor learning.

Effective sports training should be attuned to the athlete's specific conditionings and characteristics. In motor learning research, two often neglected factors that influence this resonance are the learner's athletic background and the structural diversity of exercises (e.g., relative similarity). In the setting of real-word training with higher external validity, this study examines the effects of three learning approaches (i.e., contextual interference (CI), differential learning (DL), and free-play control condition (CO)) on the parallel learning of handball (HB), volleyball (VB), and basketball (BB) skills, considering participants' prior sport backgrounds. Forty-five males (15 HB, 15 VB, and 15 BB players) with a mean age of 22 ± 1.4 years and at least 6 years of experience in the mastered discipline voluntarily participated in this study. A pre-post-retention test design including a 6-week-intervention program was employed. During the intervention period, participants engaged in three training sessions a week, with each one lasting approximately 80 min. Each of the three test sessions involved the execution of ten attempts of BB free-throw shooting, HB three-step goal throwing, and VB underarm passing following a blocked order. In terms of short-term (pre-post) gain, only the DL group significantly improved their performance in both non-mastered disciplines ( p = 0.03, ES = 1.58 for the BB free-throw and p = 0.05, ES = 0.9 for the HB shooting tests), with a trend (ES = 0.53) towards an improvement in the performance of the mastered VB underarm-pass skill. In terms of relatively permanent gains, the CI group significantly improved their performances from pre- to retention test only in the non-mastered BB free-throw skill ( p = 0.018, ES = 1.17). In contrast, the DL group significantly improved their performance at retention compared to the pre-test in both non-mastered BB ( p = 0.004, ES = 1.65) and HB ( p = 0.003, ES = 2.15) skills, with a trend (ES = 0.4) towards improvement in the mastered VB test. In both the short-term and relatively long-term, higher composite score gains were observed in DL compared to CI ( p = 0.006, ES = 1.11 and 0.049, ES = 1.01) and CO ( p = 0.001, ES = 1.73 and <0.0001, ES = 2.67). In conclusion, the present findings provide additional support for the potential advantages of the DL model over those of CI. These findings can serve as the basis for tailored training and intervention strategies and provide a new perspective for addressing various issues related to individual and situational learning.

Teaching-learning-based optimization (TLBO) algorithm is one of the recently proposed optimization algorithms. It has been successfully used for solving optimization problems in continuous spaces. To improve the optimization performance of the TLBO algorithm, a modified TLBO algorithm with differential and repulsion learning (DRLTLBO) is presented in this paper. In the proposed algorithm, the differential evolution (DE) operators are introduced into the teacher phase of DRLTLBO to increase the diversity of the new population. In the learner phase of DRLLBO, local learning method or repulsion learning method are adopted according to a certain probability to make learners search knowledge from different directions. In the local learning method, learners learn knowledge not only from the best learner but also from another random learner of their neighbors. In the repulsion learning method, learners learn knowledge from the best learner and keep away from the worst learner of their neighbors. Moreover, self-learning method is adopted to improve the exploitation ability of learners when they are not changed in some continuous generations. To decrease the blindness of random self-learning method, the history information of the corresponding learners in some continuous generations is used in self-learning phase. Furthermore, all learners are regrouped after a certain iterations to improve the local diversity of the learners. In the end, DRLTLBO is tested on 32 benchmark functions with different characteristics and two typical nonlinear modeling problems, and the comparison results show that the proposed DRLTLBO algorithm has shown interesting outcomes in some aspects. [ABSTRACT FROM AUTHOR]

Abstract In this paper, a bio-geography-based optimization techniqueis proposed for optimal sizing and placement of multiple distributed generators to reduce system loss and to improve system voltage profiles in electric distribution systems. Distributed generation paves the way for installing generating sources in the vicinity of the loads, for improving the power factor of the system, and thereby significantly reducing total system losses. An effective power factor model is proposed to pre-set the power factor of each distributed generator placed at various locations in a distribution system. The bio-geography optimization algorithm is enhanced with a differential learning scheme to deal with the problems of high dimensionality and complex constraints. A sensitivity factor approach is presented to reduce the search space for the placement of distributed generators in the system. Numerical simulations are performed on the IEEE 33-bus and IEEE 69-bus systems and the results of the proposed method are compared with other methods reported in the literature. [ABSTRACT FROM AUTHOR]

A large body of research has shown superior learning rates in variable practice compared to repetitive practice. More specifically, this has been demonstrated in the contextual interference (CI) and in the differential learning (DL) approach that are both representatives of variable practice. Behavioral studies have indicate different learning processes in CI and DL. Aim of the present study was to examine immediate post-task effects on electroencephalographic (EEG) brain activation patterns after CI and DL protocols that reveal underlying neural processes at the early stage of motor consolidation. Additionally, we tested two DL protocols (gradual DL, chaotic DL) to examine the effect of different degrees of stochastic fluctuations within the DL approach with a low degree of fluctuations in gradual DL and a high degree of fluctuations in chaotic DL. Twenty-two subjects performed badminton serves according to three variable practice protocols (CI, gradual DL, chaotic DL), and a repetitive learning protocol in a within-subjects design. Spontaneous EEG activity was measured before, and immediately after each 20-min practice session from 19 electrodes. Results showed distinguishable neural processes after CI, DL, and repetitive learning. Increases in EEG theta and alpha power were obtained in somatosensory regions (electrodes P3, P7, Pz, P4, P8) in both DL conditions compared to CI, and repetitive learning. Increases in theta and alpha activity in motor areas (electrodes C3, Cz, C4) were found after chaotic DL compared to gradual DL, and CI. Anterior areas (electrodes F3, F7, Fz, F4, F8) showed increased activity in the beta and gamma bands after CI. Alpha activity was increased in occipital areas (electrodes O1, O2) after repetitive learning. Post-task EEG brain activation patterns suggest that DL stimulates the somatosensory and motor system, and engages more regions of the cortex than repetitive learning due to a tighter stimulation of the motor and somatosensory system during DL practice. CI seems to activate specifically executively controlled processing in anterior brain areas. We discuss the obtained patterns of post-training EEG traces as evidence for different underlying neural processes in CI, DL, and repetitive learning at the early stage of motor learning. [ABSTRACT FROM AUTHOR]

The contextual interference (CI) model hypothesizes random practice (high CI) leads to inferior acquisition, but superior retention and transfer capabilities compared to blocked practice (low CI). These phenomena are well established in laboratory settings. However, the transfer to applied settings, particularly in sports practice is still under discussion. The aim of this systematic review and meta-analysis is to evaluate the possible generalisability of the CI phenomenon in sports-based contexts with regard to performance outcomes. Up to April 16th, 2022, five electronic databases (PubMed, Web of Science, Scopus, Taylor & Francis, and SciELO) were used to search for relevant studies investigating differences between blocked and random schedules at post-acquisition, retention, and/or transfer tests. Using the PICOS criteria, a total of 933 records were screened. Outcomes evaluating the acquisition, retention, and/or transfer performances in sports skills in healthy participants were included. The quality of the selected studies was scored using the PEDro scale. Thirty-seven studies were selected, of which twenty-seven were of good quality and the remaining ten were rated as fair quality. Out of 205 overall pooled outcomes, only 43 performance outcomes (21%) agreed with the CI phenomenon after the acquisition (18 out of 103), retention (19 out of 84), and/or transfer (6 out of 36) phases. No statistically significant overall difference between blocked and random practice was detected at post-acquisition (effect size (ES) = 0.1, p = 0.154), retention (ES = −0.159, p = 0.141) or transfer testing (ES = −0.243, p = 0.071). The subgroup analysis showed inferior acquisition and superior retention following random practice only in individuals aged 20–24 years (ES = 0.282, p = 0.030 during the acquisition, and ES = −0.405, p = 0.011 during retention), with no difference at transfer testing for this specific age group. No similar significant effects have been concurrently identified during both acquisition and retention phases in any of the remaining subgroups (e.g., examined based on experience level, sports, skills, and testing protocol categories). The present results suggest CI effects can only be confirmed under very limited conditions, which seriously challenges the extension of CI effects to the sport context in general. Problematic conclusions for children's learning are discussed, as well as future research strategies to better understand counterintuitive learning approaches. • Meta-Analysis found no evidence to support contextual interference effects in sports settings. • Overall performances at acquisition, retention, and transfer tests were not affected by the practice schedules. • Subgroup analysis revealed constrained conditions for corroborating contextual interference effects. • Comparing more variability-based learning perspectives is crucial for identifying optimal strategies in sports. • Comparative research should ensure an equivalent baseline and maximize design sensitivity and validity. [ABSTRACT FROM AUTHOR]