运动技能学习中影响自身觉察错误能力形成的若干因素研究--从结果反馈时间点适宜值的视角

通过不同情境中KR时间点适宜值的变化，探讨不同情境因素对自身觉察错误能力形成的影响，以期深入探测运动技能学习中自身觉察错误能力的形成机制。结果显示：只有根据操作情境的任务、个体和环境特征，在适宜的时机提供KR才能促进运动技能学习；KR时间点适宜值不是固定的点，受到诸如任务难度、任务性质、个体技能熟练程度、年龄和视觉反馈等多种情境因素的影响，不断发生变化和波动，并且在不同情境中KR时间点适宜值的变化，可以间接反映该情境中个体自身觉察错误能力形成和发展状况；运动技能学习中，个体自身觉察错误能力的形成受到任务复杂程度、任务性质、个体技能熟练程度、年龄、视觉反馈等情境因素影响。     

错误结果反馈对追踪任务学习迁移的影响

采用电脑追踪任务探讨错误结果反馈(KR)对运动技能学习迁移的影响.抽取在校大学生,随机分为正确KR组、错误KR组、混合KR组(组间性别均衡设计).在第1-3 d,3组受试者练习时分别获得正确的KR、错误的KR,或者获得25次正确KR后,再获得25次错误KR.正确的KR是每次追踪误差的毫秒数,错误的KR则是正确KR数值+10 mm.在第4 d,3组受试者分剐在无KR的条件下,用原任务进行保持测试10次,之后再操作两个迁移任务各10次.显示:KR在一致性时机任务和电脑追踪任务中的作用机理类似,当可以获得KR时,学习者将它作为觉察和纠正操作错误的信息源:错误KR会带来迁移测试绩效的偏差.提示:学习者形成自身觉察错误能力是运动技能学习的关键,实践工作者应根据运动情境的特点,合理地提供结果反馈,以促进运动技能的学习.     

不同练习量对结果反馈时间点的影响

采用两维轨迹追踪任务探讨由于练习量不同导致的技能熟练程度的差异对结果反馈(KR)时间点的影响。结果显示：延迟KR对运动技能学习的影响与练习量有关；随着运动技能熟练程度的提高，提供KR的适宜时间点向后延迟。     

主观估计错误活动、结果反馈时机与运动技能的学习

采用键盘敲击任务探讨学习者主观估计错误活动、结果反馈时机(knowledge of results,简称KR)对运动技能学习的影响.抽取90名右利手的在校大学生,随机分为:主观估计无KR组、主观估计及时KR组、主观估计延迟KR组,算术活动无KR组,算术活动及时KR组,算术活动延迟KR组(组间性别均衡设计).主观估计错误活动组在练习间以口头报告的形式评估自己刚才操作总时间的误差,算术活动组按照实验员的要求进行数字算术口头运算.无KR组不提供KR,及时KR组在主观估计错误活动或算术活动后即刻获得KR,延迟KR组则延迟4s获得KR.第1-2天,6组受试者在各自的条件下分别练习,每天练习108次.第3天,练习后,休息10min,使用原任务进行保持测试10次,要求受试者每次测试后口头报告自己操作的总时间.第4天,使用原任务进行保持测试10次,要求受试者每次测试后口头报告自己操作的总时间.结果显示:(1)练习后从事主观估计错误活动,并能及时获得KR的学习者,保持测试的绩效最好;(2)主观估计错误活动影响提供KR的适宜时机.     

延迟结果反馈对复杂追踪任务运动技能学习的影响

采用两维轨迹追踪任务探讨KR延迟对复杂追踪任务技能学习的影响，以及KR延迟间隔长度的合理值。50名右利手的在校大学生(男30名，女20名)随机分为5组，分别在即刻反馈、2s反馈、4s反馈、7s反馈、9s反馈条件下，练习7天。第7天练习后，休息10min进行无KR保持测试。第8天进行无KR的保持测试和迁移测试。研究显示：延迟KR不利于两维复杂追踪任务技能的学习。     

技能熟练程度对反馈频率适宜值的影响研究

采用两维电脑追踪任务,探讨个体技能熟练程度对反馈频率适宜值的影响作用.96名右利手在校大学生随机分为低练组和高练组(每组男、女各24名).首先,高练组受试者在100%反馈频率条件下练习2天,每天练习36次;同期,低练组受试者不进行练习,2天练习结束后,结果表明,经过不同练习量的练习,高练组受试者和低练组受试者之间形成了动作技能熟练程度的差异.此后,两组受试者分别在25%反馈频率、50%反馈频率、75%反馈频率、100%反馈频率条件下,连续2天练习两维复杂电脑追踪任务,每天练习36次.第2天练习结束后休息10 min,两组受试者进行无反馈保持测试.24 h后,再进行无反馈的保持测试.研究结果显示,获得阶段,两组受试者的操作绩效随反馈频率增加呈提高趋势;50%反馈频率有利于高练组受试的动作技能学习,75%反馈频率有利于低练组受试的动作技能学习;个体技能熟练程度与反馈频率适宜值存在交互作用,与低练组受试者相比,高练组学习动作技能时应适当减少反馈频率.提示,个体技能熟练程度影响反馈频率适宜值;技能熟练程度较高的个体学习动作技能时,应适当减少反馈频率.     

任务复杂程度对反馈频率适宜值的影响研究

采用单维简单和两维复杂电脑追踪任务,探讨任务复杂程度对反馈频率适宜值的影响.96名右利手的在校大学生随机分为简单任务和复杂任务组(每组男、女各24名).两组受试者分别在25%相对频率(提供反馈的练习次数占总练习次数的25%,简称反馈频率,下同)、50%反馈频率、75%反馈频率、100%反馈频率条件下,连续两天练习简单或复杂任务,每天练习36次.第2天练习结束后休息10min,2组受试者进行无反馈保持测试.一天后,再进行无反馈的保持测试.结果显示:(1)练习阶段,两组受试者的操作绩效随反馈频率增加呈提高趋势;(2)50%反馈频率利于简单任务的技能学习,75%反馈频率利于复杂任务的技能学习;(3)任务复杂程度与反馈频率适宜值存在交互作用,与简单任务相比,操作复杂任务时,应增加反馈的频率.以上结果提示:当信息加工负荷较小(如操作任务较简单)时,减少反馈频率利于技能学习;而当信息加工负荷较大(操作任务较复杂)时,频繁反馈利于技能学习.     

任务性质、结果反馈时机与运动技能的学习

采用键盘敲击任务探讨任务性质、结果反馈时机对运动技能学习的影响.将100名右优势手大学生随机分为开放性和封闭性任务组(男女各25名),两组分别在5种KR条件下,练习开放或封闭任务3天,每天练习108次.第3天练习结束后休息10min,进行不提供KR的保持测试10次.24 h后,进行无KR保持测试10次.结果显示:(1)在封闭性运动技能学习中延迟KR更有利,而即刻KR促进开放性运动技能的学习;(2)提供KR的适宜时机受任务性质影响.与开放性技能相比,操作封闭性技能时,提供KR的适宜时机应延迟.     

任务性质对反馈频率适宜值的影响

采用两维电脑追踪任务,探讨任务性质对反馈频率适宜值的影响。将大学生随机分为开放性任务和封闭性任务组,两组受试者分别在不同的反馈频率条件下,连续两天练习开放性或封闭性任务。结果显示:获得阶段,两组受试者的操作绩效随反馈频率增加呈提高趋势;任务性质与反馈频率适宜值存在交互作用;与封闭性任务相比,操作开放性任务时,应适当增加反馈的频率。提示:动作技能学习中,任务性质影响反馈频率适宜值。     

反馈频率对追踪任务技能学习影响的实验研究

采用单维电脑追踪任务,探讨反馈频率对追踪任务技能学习的影响作用.48名右利手的在校大学生随机分为4组(每组男、女各6人),分别按反馈次数占总练习次数比例的25%、50%、75%、100%的频率方式向各组受试者提供当前反馈.结果显示:①获得阶段,频繁反馈有利于提高操作绩效;②保持阶段,减少反馈频率有利于简单追踪任务技能学习.结论:①当前反馈对于练习者学习动作技能具有很强的指导作用,并且容易使学习者对反馈产生依赖性;②通过减少反馈频率的方式可以减少学习者对反馈的依赖作用;③追踪任务技能学习过程中存在反馈频率适宜值.     

The effects of different knowledge of results spacing and summarizing techniques on the acquisition of a ballistic movement

The present study crossed three knowledge of results summarizing techniques (single-trial KR, summary KR, and average KR) with two spacing conditions (KR on every fifth trial-20%- and KR on every trial-100%). Participants (n = 10 per group) performed 80 acquisition trials of a ballistic movement task involving both a temporal and spatial goal, followed by 30 immediate (10 min) and 30 delayed (2 days) no-KR transfer trials. For the spatial goal, performance was less accurate (absolute constant error) for the 20% spacing condition than the 100% condition during acquisition, but more accurate during delayed transfer. No effects were significant for variable error. For the temporal goal, performance was more accurate for the summary and average conditions than the single-trial KR condition; however, this effect was only present within the 20% spacing condition and only during Block 1 of acquisition. A similar effect held for variable error as well, except that the effect persisted for acquisition and transfer. It was concluded that the spacing of KR is more influential in promoting spatial accuracy than the summarizing of KR.     

Precision Knowledge of Results and Motor Performance: Relationship to Age

In motor skill performance and retention the complexity of knowledge of results should interact with the child's processing rate. This rate has been demonstrated to increase with age. Two experiments were designed to assess this hypothesis. In Experiment 1, 30 7-year-old and 30 10-year-old boys were randomly assigned within age level to three knowledge of results (KR) conditions: no KR, general KR, and precise KR. Performance was assessed on a vertical positioning task at two angles, 60° and 100°, for 10 performance trials. The preciseness of KR interacted with age and the degree of the angle, indicating that at the more difficult angle (60°) preciseness may have been detrimental to the performance of the 7-year-olds but beneficial to the 10-year-olds. At the easier angle (100°), precise KR improved performance for both age groups. In Experiment 2, 27 second-grade and 27 fourth-grade children were randomly assigned within age groups to the same three levels of KR preciseness. A horizontal curvilinear positioning task was used as the motor task and subjects were given 40 acquisition and 19 KR withdrawal trials. Results suggested that while KR was better than no KR during learning, the level of KR preciseness was of minor importance. However, the preciseness of KR during acquisition was of considerable value after KR was withdrawn (retention phase). The older children were able to use more precise KR to form a perceptual trace more resistant to forgetting, while the younger children were unable to use the additional information contained in precise KR.     

The Effect of Knowledge of Results Delay and the Subjective Estimation of Movement Form on the Acquisition and Retention of a Motor Skill

Abstract

This study examined the effects of knowledge of results (KR) delay and subjective estimation of movement form on the acquisition and retention of a motor skill. During acquisition, four groups of participants performed 60 trials of a throwing accuracy task under the following conditions: (a) immediate KR, (b) delayed KR, (c) immediate KR + form estimation, and (d) delayed KR + form estimation. Retention tests of throwing accuracy and outcome error estimation in the absence of visual KR were administered 5 min and 24 hours following acquisition. Throwing accuracy was significantly higher during acquisition but significantly lower during retention for immediate-KR participants than for delayed-KR participants. However, participants who estimated their movement form during acquisition produced significantly higher throwing accuracy and lower estimation error during retention than those who did not.     

Summary knowledge of results

Summary knowledge of results (KR) involves delaying the presentation of KR until a predetermined number of trials has been completed. Schmidt, Young, Swinnen, and Shapiro (1989) found an optimal summary length of 15 trials (compared to 1, 5, and 10) and Schmidt, Lange, and Young (1990) found an optimum length of 5 trials (compared to 1, 10, and 15) for 1 and 2 kinematic degree of freedom timing tasks, respectively. Experiment 1 was designed to determine the optimal summary length for learning a simple isometric force production task. The results indicated better retention for the 16-trial summary than for 8- or 1-trial summaries. Experiment 2 was an initial attempt to determine the locus of the 16-trial summary effect. Specifically, Experiment 2 focused on the role played by both the information provided in the summary presentations and the practice per se of the first 14 trials in the 16-trial block. The results suggest KR is important to ensure response stability. However, it also appears important to restrict the subject's immediate utilization of KR. This latter requirement may potentially aid the parameterization process, resulting in a reduction in response bias.     

An Analysis of World Weightlifting Records

Abstract

Summary knowledge of results (KR) involves delaying the presentation of KR until a predetermined number of trials has been completed. Schmidt, Young, Swinnen, and Shapiro (1989) found an optimal summary length of 15 trials (compared to 1, 5, and 10) and Schmidt, Lange, and Young (1990) found an optimum length of 5 trials (compared to 1, 10, and 15) for 1 and 2 kinematic degree of freedom timing tasks, respectively. Experiment 1 was designed to determine the optimal summary length for learning a simple isometric force production task. The results indicated better retention for the 16-trial summary than for 8- or 1-trial summaries. Experiment 2 was an initial attempt to determine the locus of the 16-trial summary effect. Specifically, Experiment 2 focused on the role played by both the information provided in the summary presentations and the practice per se of the first 14 trials in the 16-trial block. The results suggest KR is important to ensure response stability. However, it also appears important to restrict the subject's immediate utilization of KR. This latter requirement may potentially aid the parameterization process, resulting in a reduction in response bias.     

Feedback after good trials enhances learning

Recent studies (Chiviacowsky & Wulf, 2002, 2005) have shown that learners prefer to receive feedback after they believe they had a "good" rather than "poor" trial. The present study followed up on this finding and examined whether learning would benefit if individuals received feedback after good relative to poor trials. Participants practiced a task that required them to throw beanbags at a target with their nondominant arm. Vision was prevented during and after the throws. All participants received knowledge of results (KR) on three trials in each 6-trial block. While one group (KR good) received KR for the three most effective trials in each block, another (KR poor) received feedback for the three least effective trials in each block. There were no group differences in practice. However the KR good group showed learning advantages on a delayed retention test (without KR). These results demonstrated that learning is facilitated if feedback is provided after good rather than poor trials. The findings are interpreted as evidence for a motivational function of feedback.