Specificity and variability of practice, and contextual interference in acquisition and transfer of an underhand volleyball serve

The effect of contextual interference on transfer in motor learning - a systematic review and meta-analysis

Since the initial study on contextual interference (CI) in 1966, research has explored how practice schedules impact retention and transfer. Apart from support from scientists and practitioners, the CI effect has also faced skepticism. Therefore, we aimed to review the existing literature on the CI effect and determine how it affects transfer in laboratory and applied settings and in different age groups. We found 1,287 articles in the following databases: Scopus, EBSCO, Web of Science, ScienceDirect, supplemented by the Google Scholar search engine and manual search. Of 300 fully screened articles, 42 studies were included in the systematic review and 34 in the quantitative analysis (meta-analysis). The overall CI effect on transfer in motor learning was medium (SMD = 0.55), favoring random practice. Random practice was favored in the laboratory and applied settings. However, in laboratory studies, the medium effect size was statistically significant (SMD = 0.75), whereas, in applied studies, the effect size was small and statistically non-significant (SMD = 0.34). Age group analysis turned out to be significant only in adults and older adults. In both, the random practice was favored. In adults, the effect was medium (SMD = 0.54), whereas in older adults was large (SMD = 1.28). In young participants, the effect size was negligible (SMD = 0.12). Systematic review registration: https://clinicaltrials.gov/, identifier CRD42021228267.

Generalization of food devaluation following food-specific go/no-go training

The benefit of food-specific inhibition training on modulating food valuation and eating behaviors has been established, but generalization to untrained foods is seldomly examined. This study investigated whether stimulus variability and practice order, found to effect generalization in motor learning, can improve generalization following food-specific inhibition training. Ninety-three young adults practiced the Go/No-Go task online in three training conditions: 1) Constant (N = 30): inhibition practiced on one food stimulus; 2) Variable-Blocked (N = 32): inhibition practiced on 6 food stimuli, each in a separate block; and 3) Variable-Random (N = 31): inhibition practiced on 6 food stimuli in random order. Consistent with our hypothesis, the Variable-Random group showed better generalization of inhibition to untrained foods than the Constant and the Variable-Blocked groups immediately after training, demonstrating the benefit of stimulus variability and random practice order. This effect was not present 24 h after training. The Variable-Random group also showed decreased desire to eat untrained foods, exhibiting generalization of food devaluation. However, this effect was only present 24 h after training. The Constant group showed increased desire to eat untrained foods immediately and 24 h after training. The Variable-Blocked group did not differ from either group in the desire to eat to untrained foods, suggesting that random order is important for exposing the benefit of variability. The findings illustrate that presenting various training items in random order can improve generalization of food-specific inhibition training. However, inconsistencies found in the timing of generalization effects and modest effect sizes warrant additional investigation into generalization principles of food-specific inhibition training.

Feature variability determines specificity and transfer in multiorientation feature detection learning

Historically, in many perceptual learning experiments, only a single stimulus is practiced, and learning is often specific to the trained feature. Our prior work has demonstrated that multi-stimulus learning (e.g., training-plus-exposure procedure) has the potential to achieve generalization. Here, we investigated two important characteristics of multi-stimulus learning, namely, roving and feature variability, and their impacts on multi-stimulus learning and generalization. We adopted a feature detection task in which an oddly oriented target bar differed by 16° from the background bars. The stimulus onset asynchrony threshold between the target and the mask was measured with a staircase procedure. Observers were trained with four target orientation search stimuli, either with a 5° deviation (30°-35°-40°-45°) or with a 45° deviation (30°-75°-120°-165°), and the four reference stimuli were presented in a roving manner. The transfer of learning to the swapped target-background orientations was evaluated after training. We found that multi-stimulus training with a 5° deviation resulted in significant learning improvement, but learning failed to transfer to the swapped target-background orientations. In contrast, training with a 45° deviation slowed learning but produced a significant generalization to swapped orientations. Furthermore, a modified training-plus-exposure procedure, in which observers were trained with four orientation search stimuli with a 5° deviation and simultaneously passively exposed to orientations with high feature variability (45° deviation), led to significant orientation learning generalization. Learning transfer also occurred when the four orientation search stimuli with a 5° deviation were presented in separate blocks. These results help us to specify the condition under which multistimuli learning produces generalization, which holds potential for real-world applications of perceptual learning, such as vision rehabilitation and expert training.

Stimulus variability improves generalization following response inhibition training

The present study examined the effect of stimulus variability and practice order on generalization to novel stimuli following a single session of response inhibition training. Ninety-six young adults practiced the Go/No-go task online in three training conditions: (1) constant (N = 32)-inhibition practiced on one stimulus; (2) variable-blocked (N = 32)-inhibition practiced on 6 stimuli, each in a separate block; and (3) variable-random (N = 32)-inhibition practiced on 6 stimuli in random order. Generalization was measured by comparing groups on inhibition of novel stimuli and a trained stimulus immediately and 24 h after training. Consistent with our hypothesis, the variable-random and the variable-blocked groups showed better generalization to the novel items than the constant group, demonstrating the benefit of stimulus variability. The variable-random group also showed better generalization than the variable-blocked group, demonstrating the benefit of presenting stimuli in random order. Participants' capacity for working memory maintenance was found to modulate the effect of practice order. While the benefit of variability was retained 24 h after training, the effect of order was not. Results also show generalization to (1) different type of stimuli using the same task and (2) the same stimuli on a different response inhibition task (the Stop-Signal Task), however, the effect of variable practice and order were not evident in these cases. The study findings illustrate the advantage of using variable stimuli presented in random order for generalization and suggest that these principles of motor learning can be applied to learning of cognitive skills.

Interactive curriculum learning increases and homogenizes motor smoothness

One of the challenges of technology-assisted motor learning is how to adapt practice to facilitate learning. Random practice has been shown to promote long-term learning. However, it does not adapt to the learner's specific learning requirements. Previous attempts to adapt learning considered the skill level of learners from past training sessions. This study investigates the effects of personalizing practice in real time, through a curriculum learning approach, where a curriculum of tasks is built by considering consecutive performance differences for each task. 12 participants were allocated to each of three training conditions in an experiment which required performing a steering task to drive a cursor in an arc channel. The curriculum learning approach was compared to two other conditions: random practice and another adaptive practice, which does not consider the learning evolution. The curriculum learning practice outperformed the random practice in effectively increasing movement smoothness at post-test and outperformed both the random practice and the adaptive practice on transfer tests. The adaptation of practice through the curriculum learning approach also made learners' skills more uniform. Based on these findings, we anticipate that future research will explore the use of curriculum learning in interactive training tools to support motor skill learning, such as rehabilitation.

The learning of sprint hurdles: A comparative study on increasing contextual interference and blocked practice schedules

The contextual interference (CI) approach has proposed that a random order of practice for motor skills is superior in facilitating learning compared to a blocked arrangement of practice trials. Two groups of physical education students learned sprint hurdles, employing either an increasing CI practice schedule (n = 23) or a blocked practice schedule (n = 23). In both the practice schedules, the same exercises were used in a different trial order during each learning session. Eleven practice sessions were conducted over a period of six weeks, with two days of practice per week. Ten and 40 days after the acquisition phase, a retention and transfer test were conducted. The results showed no differences between the two practice schedules during the retention tests. However, students practicing with an increasing CI arrangement performed better on the delayed transfer test compared to students which practiced with a blocked schedule. Specifically, the increasing CI group more effectively (p < 0.05) cleared the hurdles due to a lower take-off step angle and longer step length than the blocked practice group. Although utilizing an increase in CI during the learning phase of sprint hurdling produced more persistent learning effects relative to a traditional blocked practice schedule for adult novice learners, further research is warranted to explore the CI effect across a broader range of sport skills.

Effects of biofeedback on biomechanical factors associated with chronic ankle instability: a systematic review with meta-analysis

BACKGROUND

Biofeedback may alter the biomechanics of lower extremities in patients with chronic ankle instability (CAI). We aimed to systematically review the literature on the effect of gait-training and biofeedback on biomechanical parameters in individuals with CAI and conduct a meta-analysis.

METHODS

We searched four databases including PubMed, Web of Science, Scopus and Embase from their inception through 30th June 2022. The Downs and Black appraisal scale was applied to assess quality of included studies. Two reviewers screened studies to identify those reporting the effect of biofeedback on biomechanical factors associated with CAI. Outcomes of interest were kinetics and kinematics. Two authors separately extracted data from included studies. Data of interest were study design, number of sessions, intervention, tools, outcomes, number, sex, age, height, and body mass of participants.

RESULTS

Thirteen studies with a total of 226 participants were included. Biofeedback was capable of shifting center of pressure (COP) and lateral plantar pressure medially and reducing foot inversion, adduction, propulsive vertical ground reaction force (vGRF), ankle joint contact force, peak pressure and pressure time integral in the lateral mid-foot and forefoot. Auditory biofeedback had agreater impact on modifying plantar pressure in individuals with CAI. The meta-analyses revealed that visual biofeedback reduces peak pressure in lateral mid-foot and pressure time integral at lateral and medial heel and pressure increases under the hallux.

CONCLUSION

Biofeedback can alter pressure, vGRF, and foot inversion associated with CAI. Auditory biofeedback had greater impact on modifying plantar pressure in individuals with CAI. Further studies are required to assess the prolonged effect and clinical consequences of biofeedback or a combination of feedback on CAI in different age groups. Moreover, developing a low-cost and user-friendly device that can be evaluated in high quality RCTs is important prior to implementing the intervention in the clinical setting to reduce symptoms of CAI.

The role of lag effect in distributed practice on learning novel vocabulary

PURPOSE

The purpose of the current study was to investigate the lag effects in two different versions of distributed practice on learning novel language vocabulary.

METHOD

Forty-four healthy monolingual English-speaking participants were randomly assigned to two versions of distributed practice. The two versions of distributed practice were created by altering the temporal lag between the practice sessions. Participants in both groups completed a similar practice regimen wherein they practiced 30 French occupations five times each for a total of 150 times. The pre/post-design employed in this experiment involved participants completing baseline, immediate, and delayed retention tests. The outcome measures included a comprehensive multiple-choice test and a written expression task.

RESULTS

The findings from the comprehensive and expressive tasks indicated that the learning performance of participants across both groups was better during the immediate retention test compared to the delayed retention test. With regard to the group, participants assigned to the condensed version of distributed practice demonstrated superior learning of the novel vocabulary over participants assigned to the extended version of distributed practice.

CONCLUSION

The findings indicate that an increased temporal lag between the practice sessions results in a "non-monotonic function," wherein the learning continues to improve until an optimal lag, after which the learning declines as the lag continues to increase. This line of research will have a substantive impact on service-delivery models in speech-language pathology.

A randomized crossover single-case series comparing blocked versus random treatment for anomia

The motor learning literature has demonstrated that blocked practice facilitates better acquisition of motor skills, whereas random practice facilitates retention and transfer. The verbal learning and memory literature offers similar evidence. The purpose of this study was to investigate effects of blocked versus random practice in treatment for anomia. The study used a single site, randomized crossover design, with two replicated experimental phases (two blocked and two random) for each of 10 individuals with anomia. Each phase consisted of a cued picture-naming treatment. Individual treatment and maintenance effects, as well as weighted averages and group effects, were calculated using Tau-U based on the proportion of correctly named probes. Nine of 10 participants demonstrated treatment effects during each of the four phases. Acquisition was comparable for blocked and random practice. Maintenance effects were observed following seven blocked phases of treatment and 12 random phases of treatment across participants. For four of 10 participants the random schedule resulted in better maintenance of trained items. Although further research is needed, the present data suggest that for word retrieval treatment with multiple repetitions of the same items, a random presentation may benefit maintenance of treatment gains.

Learning Multiple Movements in Parallel-Accurately and in Random Order, or Each with Added Noise?

Traditionally, studies on learning have mainly focused on the acquisition and stabilization of only single movement tasks. In everyday life and in sports, however, several new skills often must be learned in parallel. The extent to which the similarity of the movements or the order in which they are learned influences success has only recently begun to attract increased interest. This study aimed to compare the effects of CI in random practice order (high CI) with differential learning (DL) in learning three volleyball skills in parallel. Thirty-two advanced beginners in volleyball (mean age = 24, SD = 2.7) voluntarily participated in the study. Within a pre-, post-, retention test design, an intervention of six weeks and one week retention phase, the effects of three practice protocols of a CI, DL, and control (CO) group were compared. Three different volleyball skills (underhand pass, overhand pass, and overhand serve) were trained with emphasis on accuracy. Results showed statistically significant higher rates of improvement in the acquisition and learning phases for the DL group compared to the CI and CO groups. The differences were associated with moderate to high effect sizes in all individual skills and in the combined skills. The findings show more agreement with DL than with CI theory.

Immediate effects of vibration biofeedback on ankle kinematics in people with chronic ankle instability

BACKGROUND

People with chronic ankle instability are more inverted during initial contact and loading response which may increase the risk of subsequent ankle injuries. Vibration feedback gait retraining causes medial center of pressure shifts but its impact on ankle kinematics remains unknown. The purpose of this study was to understand kinematic ankle changes in people with chronic ankle instability following vibration feedback gait retraining.

METHODS

Nineteen participants with chronic ankle instability walked with vibration feedback for 10 min on a treadmill and for one mile in the real-world. A vibration stimulus occurred at the lower leg when pressure under the 5th metatarsal exceeded a threshold. Three-dimensional kinematics of the ankle were recorded in the lab before and after training. Paired t-tests compared baseline and posttest ankle, hindfoot, and forefoot positions during initial contact and loading response for the lab and real-world conditions.

FINDINGS

After lab training the ankle (mean difference:-1.68 ± 1.62°, effect size:0.95) and forefoot (mean difference:-1.68 ± 1.67°, effect size:0.92) were more abducted. After real-world training, the ankle (mean difference:-1.19 ± 2.12°, effect size:0.54) and forefoot (mean difference:-1.87 ± 3.00°, effect size:0.63) were more everted. Similarly the ankle (mean difference:-2.37 ± 4.79°, effect size:0.46) and forefoot (mean difference:-2.78 ± 4.91°, effect size:0.51) were more abducted after real-world training.

INTERPRETATION

Vibration feedback decreases inversion and adduction during loading response. However, RW compared to lab training may have more beneficial frontal plane changes for people with chronic ankle instability.

Interleaved practice benefits implicit sequence learning and transfer

Compared to blocked practice, interleaved practice of different tasks leads to superior long-term retention despite poorer initial acquisition performance. This phenomenon, the contextual interference effect, is well documented in various domains but it is not yet clear if it persists in the absence of explicit knowledge in terms of fine motor sequence learning. Additionally, while there is some evidence that interleaved practice leads to improved transfer of learning to similar actions, transfer of implicit motor sequence learning has not been explored. The present studies used a serial reaction time task where participants practiced three different eight-item sequences that were either interleaved or blocked on Day 1 (training) and Day 2 (testing). In Experiment 1, the retention of the three training sequences was tested on Day 2 and in Experiment 2, three novel sequences were performed on Day 2 to measure transfer. We assessed whether subjects were aware of the sequences to determine whether the benefit of interleaved practice extends to implicitly learned sequences. Even for participants who reported no awareness of the sequences, interleaving led to a benefit for both retention and transfer compared to participants who practiced blocked sequences. Those who trained with blocked sequences were left unprepared for interleaved sequences at test, while those who trained with interleaved sequences were unaffected by testing condition, revealing that learning resulting from blocked practice may be less flexible and more vulnerable to testing conditions. These results indicate that the benefit of interleaved practice extends to implicit motor sequence learning and transfer.

What Is the Level of Contextual Interference in Serial Practice? A Meta-Analytic Review

For over 40 years, the contextual interference effect in motor learning has been investigated. While the difference between levels of contextual interference experienced under blocked and random practice are well established, the difference in the levels of contextual interference experienced under serial and random practice is still ambiguous. Therefore, a meta-analytic review was conducted to clarify this inconsistency. We focused on one question: Do random practice and serial practice have the same effect on motor learning? ISI Web of Science, PubMed, and Scopus database were searched. Nine studies were included. The results of our meta-analyses show that serial and random practices present the same results in terms of performance in retention and transfer tests. This result is aligned to the original finding of the contextual interference effect, as well as its explanatory hypotheses. In addition, a complementary explanation in defense of the same mechanisms operating in serial and random practices is discussed. In conclusion, our results suggest that serial practice present high contextual interference.

Effects of contextual interference on feeding training in patients with stroke

The contextual interference (CI) effect of motor skill has been demonstrated through numerous studies. However, few studies have reported on daily living tasks in patients with stroke. This study investigated the CI effect on spooning training in such patients. Fourteen right hemiparetic patients with stroke were assigned to one of two groups: a group with a random practice schedule or a group with a blocked practice schedule. The spooning task involved scooping go stones from a bowl 30 cm away in 3 different directions to a bowl in front of the patient. We evaluated the acquisition, retention, and transfer of motor learning for spooning. The transfer was evaluated while participants ate cereal in a bowl with a spoon. Upper extremity function, defined as far-transfer, was also evaluated using the box-and-block test. In the retention test, no significant difference between random and blocked practice groups was shown, although both groups showed differences between pre-test and post-test movement times. However, in the transfer test, the random practice group had a significantly shorter movement time than the blocked practice group and also revealed improvement between the pre- and follow-up tests. Additionally, in the far-transfer test, there were significant differences between the pre- and post-, and pre- and follow-up tests only in the random practice group. These findings show that the benefits of CI for transfer can be applied to the learning of feeding skills in patients with stroke and that although the blocked practice is also partially beneficial to long-lasting skill learning in a treatment setting, it may not be efficient under changed conditions. We also suggest the possibility that feeding training with the CI effect could apply to not only transfer but also to far-transfer.

Dissociable effects of practice variability on learning motor and timing skills

Motor skill acquisition inherently depends on the way one practices the motor task. The amount of motor task variability during practice has been shown to foster transfer of the learned skill to other similar motor tasks. In addition, variability in a learning schedule, in which a task and its variations are interweaved during practice, has been shown to help the transfer of learning in motor skill acquisition. However, there is little evidence on how motor task variations and variability schedules during practice act on the acquisition of complex motor skills such as music performance, in which a performer learns both the right movements (motor skill) and the right time to perform them (timing skill). This study investigated the impact of rate (tempo) variability and the schedule of tempo change during practice on timing and motor skill acquisition. Complete novices, with no musical training, practiced a simple musical sequence on a piano keyboard at different rates. Each novice was assigned to one of four learning conditions designed to manipulate the amount of tempo variability across trials (large or small tempo set) and the schedule of tempo change (randomized or non-randomized order) during practice. At test, the novices performed the same musical sequence at a familiar tempo and at novel tempi (testing tempo transfer), as well as two novel (but related) sequences at a familiar tempo (testing spatial transfer). We found that practice conditions had little effect on learning and transfer performance of timing skill. Interestingly, practice conditions influenced motor skill learning (reduction of movement variability): lower temporal variability during practice facilitated transfer to new tempi and new sequences; non-randomized learning schedule improved transfer to new tempi and new sequences. Tempo (rate) and the sequence difficulty (spatial manipulation) affected performance variability in both timing and movement. These findings suggest that there is a dissociable effect of practice variability on learning complex skills that involve both motor and timing constraints.

Role of Constant, Random and Blocked Practice in an Electromyography-Based Oral Motor Learning Task

PURPOSE

The role of principles of motor learning (PMLs) in speech has received much attention in the past decade. Oral motor learning, however, has not received similar consideration. This study evaluated the role of three practice conditions in an oral motor tracking task.

METHOD

Forty-five healthy adult participants were randomly and equally assigned to one of three practice conditions (constant, blocked, and random) and participated in an electromyography-based task. The study consisted of four sessions, at one session a day for four consecutive days. The first three days sessions included a practice phase, with immediate visual feedback, and an immediate retention phase, without visual feedback. The fourth session did not include practice, but only delayed retention testing, lasting 10-15 minutes, without visual feedback.

RESULTS

Random group participants performed better than participants in constant and blocked practice conditions on all the four days. Constant group participants demonstrated superior learning over blocked group participants only on day 4.

CONCLUSION

Findings indicate that random practice facilitates oral motor learning, which is in line with limb/speech motor learning literature. Future research should systematically investigate the outcomes of random practice as a function of different oral and speech-based tasks.

Effects of practice variability on spinal manipulation learning

OBJECTIVE

To evaluate the effects of practice variability on chiropractic students' capacity to deliver spinal manipulations (SMs) of a targeted peak force.

METHODS

Forty students participated in an experimental session including either a variable or a constant practice protocol of 45 SMs. SMs were delivered on a computer-connected device that recorded force-time profiles. Ten SMs with a target peak force of 350-N were performed before practice, immediately following practice, and 2 days later. Mixed-design analyses of variance were used to assess the effect of practice type on SM biomechanical parameters and on the constant, the absolute error (AE), and the variable error (VE).

RESULTS

The practice period led to significantly more accurate (F_AE[2,76] = 6.17, p < .01) and consistent (F_VE[2,76] = 3.90, p = .02) performances at the postintervention assessment regardless of practice type. Among biomechanical parameters, preload force was higher at the retention assessment than at baseline (F[2,76] = 6.53, p < .01), while rate of force application significantly decreased between the baseline and the retention assessment (F[2,76] = 4.10, p = .02).

CONCLUSION

This experimental study showed that 1 session of SM practice including feedback leads to an increase in SM peak force accuracy and consistency, whether or not the practice period included variable practice. The current results confirmed that short practice periods with feedback should be included in the chiropractic curriculum.

Effects of variability of practice in music: a pilot study on fast goal-directed movements in pianists

Variability of Practice (VOP) refers to the acquisition of a particular target movement by practicing a range of varying targets rather than by focusing on fixed repetitions of the target only. VOP has been demonstrated to have beneficial effects on transfer to a novel task and on skill consolidation. This study extends the line of research to musical practice. In a task resembling a barrier-knockdown paradigm, 36 music students trained to perform a wide left-hand interval leap on the piano. Performance at the target distance was tested before and after a 30-min standardized training session. The high-variability group (VAR) practiced four different intervals including the target. Another group (FIX) practiced the target interval only. A third group (SPA) performed spaced practice on the target only, interweaving with periods of not playing. Transfer was tested by introducing an interval novel to either group. After a 24-h period with no further exposure to the instrument, performance was retested. All groups performed at comparable error levels before training, after training, and after the retention (RET) interval. At transfer, however, the FIX group, unlike the other groups, committed significantly more errors than in the target task. After the RET period, the effect was washed out for the FIX group but then was present for VAR. Thus, the results provide only partial support for the VOP hypothesis for the given setting. Additional exploratory observations suggest tentative benefits of VOP regarding execution speed, loudness, and performance confidence. We derive specific hypotheses and specific recommendations regarding sample selection and intervention duration for future investigations. Furthermore, the proposed leap task measurement is shown to be (a) robust enough to serve as a standard framework for studies in the music domain, yet (b) versatile enough to allow for a wide range of designs not previously investigated for music on a standardized basis.

Effect of Specific versus Variable Practice upon Overhead Throwing Speed in Children

This study compared the effect of practice throwing with specific weights (specificity principle) or with variable weights (variability of practice) for a short practice period in children. Primary school children ( N = 41; M age = 7.7 yr., SD = 0.5) were randomly divided into three homogenous groups. The first two groups used specific overhead throwing practice: throws with a soccer ball or 1 kg balls, while the third group used variable practice with 0.35, 0.45, 0.5, and 1 kg balls. All groups trained twice per week for six weeks. The same workload per session between the three groups varied from 24 throws (1 kg practice group) to 43 throws (soccer ball practice group). Throwing speed and distance with different balls was measured before and after the practice period. Statistically significant increases in performance in all three practice groups were found with no significant differences between groups. The results indicate that both specific and variable practice of throwing in children lead to increases in performance. However, it seems that the increased workload (practice) is a more important factor than the type of practice (specific or variable) in enhancing performance in children.

Too much of a good thing: random practice scheduling and self-control of feedback lead to unique but not additive learning benefits

We examined the impact of self-controlled knowledge of results on the acquisition, retention, and transfer of anticipation timing skill as a function of random and blocked practice schedules. Forty-eight undergraduate students were divided into experimental groups that practiced under varying combinations of random or blocked as well as self-controlled or yoked practice conditions. Anticipation timing performance (5, 13, and 21 mph) was recorded during acquisition and during a short term no-feedback retention test. A transfer test, administered 24 h after the retention test, consisted of two novel anticipation timing speeds (9, 17 mph). Absolute error (AE) and variable error (VE) of timing served as the dependent measures. All participants improved their accuracy and consistency across acquisition blocks; however, those who practiced under blocked rather than random conditions had greater accuracy (lower AE) regardless of feedback delivery. During retention and transfer, those who practiced under random conditions showed greater consistency (lower VE) compared to their blocked counterparts. Finally, participants who controlled their feedback schedule were more accurate (lower AE) and less variable (lower VE) during transfer compared to yoked participants, regardless of practice scheduling. Our findings indicate that practicing under a random schedule improves retention and transfer consistency, while self-control of feedback is advantageous to both the accuracy and consistency with which anticipation timing skill transfers to novel task demands. The combination of these learning manipulations, however, does not improve skill retention or transfer above and beyond their orthogonal effects.