The contextual interference effect in acquisition of dart-throwing skill tested on a transfer test with extended trials

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.

Learner-adapted practice promotes skill transfer in unskilled adults learning the basketball set shot

The current study used a complex, sport-specific movement skill to explore the effects of a win-shift/lose-stay practice schedule on learning and compared its effectiveness with that of blocked and random practice schedules. Thirty-six adults (24.9 ± 3.3 years) were assigned to blocked, random and learner-adapted training groups. Each participant performed 360 trials of the basketball set shot from multiple locations across six practice sessions. For the learner-adapted group, switching between task variations was performance-contingent; switching between shooting locations occurred only following a successful shot. Shooting success was calculated as the percentage of successful shots performed, and measured during pre-acquisition (i.e. baseline), acquisition (i.e. practice) and post-acquisition (i.e. retention and transfer). Despite scoring less shots throughout practice compared to baseline testing, the learner-adapted group showed a significant improvement for shooting success in transfer (d = 1.02). Blocked practice demonstrated significant improvements for shooting success in immediate retention (d = 1.83), delayed retention (d = 1.69) and transfer (d = 1.39). Random practice significantly improved shooting success in both immediate (d = 1.03) and delayed retention (d = 0.81). The current findings highlight that performance during practice does not necessarily represent the permanency and adaptability of skill learning. The implications of the findings and their practical applications are discussed in the context of practice scheduling during learning of a sports skill.

Does the Contextual Interference Effect Last over Extended Transfer Trials?

The contextual interference effect (random practice yields better transfer and retention compared to blocked practice) detected in a study of 24 boys and 33 girls randomly selected ( M age = 10.5 yr., SD = .6) performing a linear positioning motor task seemed to dissipate in extended transfer trials.

Contextual Interference: A Meta-Analytic Study

A meta-analysis of the contextual interference effect produced 139 estimates of effect sizes from 61 studies. The average overall effect size was .38. The effect size for basic research (.57) was significantly different from applied research (.19). Significant differences were also obtained between the effect sizes for adults (.50) and those for younger learners (.10). Power for retention and transfer scores was not significantly different. The overall mean power of the studies reviewed was .43.

Reality, virtual reality, and imagery: Quality of movement in novice dart players

Introduction

Meaning and purpose have been tenets of occupational therapy since the profession’s inception. Therefore, it is important to understand how to best employ these central concepts in practice. One way to do this is to study the “same” task under materials-based, imagery-based, and virtual reality conditions.

Method

Participants included 34 adult novice dart players, each of whom experienced all three conditions in a randomized order. Motion capture technology was used to evaluate the quality of motion during the three conditions.

Results

Similarities between the materials-based and imagery-based condition ( p > 0.0167) suggest participants utilized preconceived concepts of throwing real darts during these two conditions. Differences between the virtual reality and imagery-based conditions ( p < 0.0167) suggest that the virtual reality condition utilized a different motor performance, focusing less on perceptions of throwing darts and more on achieving successes within the virtual environment.

Conclusion

Implications are that utilizing materials-based occupations may be more efficient than imagery-based to enhance development of a skill; imagery-based performance is more similar to the materials-based performance than the virtual reality performance. Virtual reality occupations can be utilized should the patient find meaning and purpose in virtual reality occupations or if the patient cannot engage in a materials-based counterpart.

CONTEXTUAL INTERFERENCE AND INTROVERSION/EXTRAVERSION IN MOTOR LEARNING

The Introversion/Extraversion dimension may interact with contextual interference, as random and blocked practice schedules imply distinct levels of variation. This study investigated the effect of different practice schedules in the acquisition of a motor skill in extraverts and introverts. Forty male undergraduate students (M = 24.3 yr., SD = 5.6) were classified as extraverts (n = 20) and introverts (n = 20) by the Eysenck Personality Questionnaire and allocated in one of two practice schedules with different levels of contextual interference: blocked (low contextual interference) and random (high contextual interference). Half of each group was assigned to a blocked practice schedule, and the other half was assigned to a random practice schedule. The design had two phases: acquisition and transfer (5 min. and 24 hr.). The participants learned variations of a sequential timing keypressing task. Each variation required the same sequence but different timing; three variations were used in acquisition, and one variation of intermediate length was used in transfer. Results for absolute error and overall timing error (root mean square error) indicated that the contextual interference effect was more pronounced for introverts. In addition, introverts who practiced according to the blocked schedule committed more errors during the 24-hr. transfer, suggesting that introverts did not appear to be challenged by a low contextual interference practice schedule.

Environmental context affects outcome and kinematic changes at different rates during skill learning

Based on Gentile's learning model, this study used a dart-throwing task to investigate the influence of environmental context. Novice participants (N = 32) were trained in one of four conditions, while measuring outcomes and kinematics. The interaction of regulatory conditions (stationary/in motion) and intertrial variability (present/absent) created four target conditions: (1) stationary with one location, (2) stationary with five locations, (3) moving with one movement pattern, (4) moving with five starting locations. Performance outcome (radial error) and movement coordination (displacement of shoulder, elbow, and wrist) changes were investigated during three days of practice (480 trials). Radial error scores were analyzed using a 3 x 8 x 4 (Day x Trial Block x Condition) analysis of variance, repeated measures design. The transformed cross-correlation values of the kinematic trials were analyzed using a 3 x 3 x 4 (Joint x Day x Condition) analysis of variance, repeated measures design. Reducing the environmental context complexity of the skill (closed regulatory conditions and no inter-trial variability), decreased outcome errors and changed kinematics at different times in the learning. The environmental context influence was observed by a day x condition interaction on joint coordination. Inter-trial variability had its greatest influence on coordination. The environmental context should be taken into consideration when evaluating and assessing skill performance during learning.

Contextual interference effects on the acquisition of skill and strength of the bench press

The purpose of this study was to investigate contextual interference effects on skill acquisition and strength gains during the learning of the bench press movement. Twenty-four healthy, college-aged males and females were stratified to control, high contextual interference (HCI), and low contextual interference (LCI) groups. Treatment groups were provided with written and visual instruction on proper bench press form and practiced the bench press and dart throwing for four weeks. Within each session, LCI performed all bench press sets before undertaking dart-throws. HCI undertook dart-throws immediately following each set of bench press. Control only did testing. Measurements, including one repetition maximum (1RM), checklist scores based on video recordings of participants' 1RM's, and dart-throw test scores were taken at pre-test, 1 week, 2 week, post-test, and retention test. Results were consistent with the basic premise of the contextual interference effect. LCI had significant improvements in percent 1RM and checklist scores during training, but were mostly absent after training (post-test and retention test). HCI had significant improvements in percent 1RM and checklist scores both during and after training. Thus, HCI may augment strength and movement skill on the bench press since proper technique is an important component of resistance exercise movements.

Neural correlate of the contextual interference effect in motor learning: a kinematic analysis

The contextual interference (CI) effect affirms that learning is enhanced when interference during practice is high, such as when participants practice multiple tasks in a random order. Previous research showed a distinct response in the cortical motor (CM) regions of participants performing under high CI practice conditions compared with low CI conditions. Specifically, there was increased corticomotor activity in a high CI condition when participants practiced 3 arm tasks, each with specific spatial and temporal requirements. Using disruptive transcranial magnetic stimulation (TMS), the authors' purpose was to determine whether CM is preferentially processing the spatial, temporal, or both parameters of the task during high CI practice. Participants were randomized to 1 of 6 practice conditions derived from 3 stimulation conditions (no TMS, TMS, sham TMS) and 2 CI conditions (blocked [low CI] and random [high CI]). The authors measured performance accuracy in movement timing (temporal) and amplitude (spatial) across practice and no-stimulation recall phases. TMS perturbation deterred learning of movement timing under random, but not blocked, practice order; the authors did not observe this in spatial parameter learning. The authors' data suggest that increased corticomotor activity during high CI practice may reflect preferential processing of the temporal parameter of the task.

How persistent and general is the contextual interference effect?

The persistence and generality of the contextual interference (CI) effect was tested using a rapid sequential aiming task. Participants (N=48) practiced three movement patterns for three blocks of 18 trials under a blocked (BL) or random (RA) schedule. Movement patterns were displayed and KR provided throughout practice and testing. A 24-hr delayed knowledge of results (KR) retention test included three blocks of 18 trials, followed by a transfer test of a single new movement pattern. In contradiction of the CI effect, RA practice provided an advantage for RA retention only, not BL retention. Furthermore, group differences at transfer were not persistent. Hence, RA practice does not necessarily provide enhanced, context-free learning, but it is essential training for task switching. Overall the findings reveal limited persistence and generality of the CI effect.

Effect of task practice order on motor skill learning in adults with Parkinson disease: a pilot study

BACKGROUND AND PURPOSE

Random practice of motor tasks has been shown to enhance motor learning. The purpose of this study was to investigate the effects of task practice order (random, blocked) on motor learning in adults with Parkinson disease (PD).

SUBJECTS

Twenty adults with mild PD and 20 age-matched adults (controls) participated in the study.

METHODS

Participants in both groups (PD and control) practiced 3 movement tasks with either a blocked or a random practice order. This 2 participant group x 2 practice order design resulted in 4 experimental groups. The Trail Making Test was administered to all participants to determine task-switching capability. Motor performance on the arm movement tasks was quantified on the basis of the root-mean-square error difference between the goal movement task and each participant's response.

RESULTS

The task-switching capability of the control group was superior to that of the PD group. For acquisition, in general, participants in the control group performed with significantly less error than participants in the PD group. For retention, participants in the control group who practiced with a random order performed more accurately than participants in the control group who practiced with a blocked order. However, for the PD group, the findings were reversed; participants who practiced with a blocked order performed more accurately than participants who practiced with a random order. These findings resulted in a group x practice order interaction.

DISCUSSION AND CONCLUSION

These pilot study data suggest that, contrary to the findings for age-matched control learners, for learners with mild PD, a blocked practice order may be better than a random practice order for motor learning.