The Specificity of Motor Skill and Manual Asymmetry: A Review of the Evidence and Its Implications

Results of investigations on gaining control of limb movements are reviewed, and their contribution to understanding the development of manual asymmetries is discussed in relation to the discrimination and programming of appropriate neuromuscular resources. An examination of the relevant evidence on number and types of manual asymmetries recorded provides strong grounds for concluding that where asymmetries occur, they simply represent a further example of the well-documented activity-specific nature of motor skills and of the extremely lengthy periods of learning or experience needed for their acquisition and perfection. This specificity of motor skill and manual asymmetry also readily accounts for most of the discrepancy usually reported between assessments of hand preference and performance differences between hands, because these alternative measures of handedness have rarely employed the same range or variety of tasks.     

Challenge Point: A Framework for Conceptualizing the Effects of Various Practice Conditions in Motor Learning

The authors describe the effects of practice conditions in motor learning (e.g., contextual interference, knowledge of results) within the constraints of 2 experimental variables: skill level and task difficulty. They use a research framework to conceptualize the interaction of those variables on the basis of concepts from information theory and information processing. The fundamental idea is that motor tasks represent different challenges for performers of different abilities. The authors propose that learning is related to the information arising from performance, which should be optimized along functions relating the difficulty of the task to the skill level of the performer. Specific testable hypotheses arising from the framework are also described.     

Sensorimotor synchronization: Motor responses to pseudoregular auditory patterns

Musically trained and untrained subjects (N=30) were asked to synchronize their finger tapping with stimuli in auditory patterns. Each pattern comprised six successive tonal stimuli of the same duration, the first of which was accented by a different frequency. The duration of interstimulus onset intervals (ISIs) gradually increased or decreased in constant steps toward the end of the patterns. Four values of such steps were used in different trials: 20, 30, 45, and 60 msec. Various time-control mechanisms are hypothesized as being simultaneously responsible for subjects’ incorrect reproduction of the internal temporal ratios of the stimulus patterns. The mechanism of assimilation (of a central tendency) led subjects to enforce a regular (isochronous) structure on the patterns. The influence of other time-control mechanisms (distinction, subjective expression of an accent, sequential transfer) was expressed mainly in differences between intertap onset intervals (ITIs) and the corresponding ISIs at the beginning of the patterns. The duration of the first two ITIs was in the majority of the trials in an inverse ratio to the ratio of the respective ISIs. The distortions resulting from the timing mechanisms concerned were more pronounced in the performance of nonmusicians than in that of musicians.     

Sensorimotor synchronization: Motor responses to regular auditory patterns

Subjects (N = 32) were asked to synchronize a motor response with tones in auditory patterns. These patterns were created from six tones and six intertone intervals of equal duration. The pitch of the first tone differed from the others. It was found that subjects used three types of timing in their motor response: (1) the first intertone interval was prolonged and the second interval was shortened, (2) the second intertone interval was prolonged and the first interval was shortened, and/or (3) the first interval and the second interval were of approximately the same length. The prolongation of the fifth interval was observed during all three types of timing. The results are explained using the concept of suprasegmental control of timing, which explains a prolongation of intervals at critical control point of the patterns. The occurrence of three different strategies of timing is discussed in connection with similar principles in musical performance.     

Sensorimotor fluency influences affect: Evidence from electromyography

Fluency of visual processing induces affective responses, with easier-to-process stimuli being preferred (Winkielman & Cacioppo, 2001). The present study extends this research to the motor domain by investigating the effect of sensorimotor fluency on affective reactions to objects in a categorisation task. In fluent stimulus–response (s–r) trials, grasp-compatible objects were presented on the same side of the screen as the response hand; in non-fluent trials, grasp incompatible objects were presented on the opposite side of the screen to the response hand. Affective responses were measured implicitly using face muscle activity (electromyography). As predicted, participants exhibited greater cheek muscle activity (associated with smiling) in trials with s–r compatible responses compared with incompatible responses. These findings support hedonic models of fluency in which fluent processing elicits direct emotional experience, and suggest that models of hedonic fluency should take into account the integration of the motor system in visual processing.     

记忆提取促进学习:实验证据与机制解释

人类学习的主流观点认为学习主要发生在编码阶段,记忆提取本身并不产生和促进学习。但最近多项研究对此提出了质疑,他们发现,在学习过程中,记忆提取更能促进学习内容的长时保持。本文首先对记忆提取促进学习的实验证据做简要梳理;之后重点介绍关于记忆提取促进学习的多种解释机制,主要包括:侧重于从理论机制层面解释的记忆失用新理论,强调内在精细机制的精细提取假设,以及解释保持间隔(长、短)与学习方式(重复学习、学习-测试)交互作用的基于分布的二分模型;文章最后分析了当前研究记忆提取作用实验存在的一些问题,提出了今后的研究方向,强调应从多角度揭示记忆提取练习促进学习的机制。     

Variability of Practice and Contextual Interference in Motor Skill Learning

The purpose of this study was to investigate whether learning benefits in multiple-task learning situations are a result of contextual interference or of schema enhancement related to the amount of variability in the practice session. Two experiments were designed that replicated and extended the experiment reported by Wulf and Schmidt (1988). In a 2 (same vs. different relative time) x 2 (blocked vs. random practice schedule) design, 48 right-handed subjects were randomly assigned to one of four experimental conditions. A tapping task was employed that required a right-handed tap of three small brass plates arranged in a diamond pattern. Each segment had a specific time requirement. Target times and response times were provided on a computer screen directly in front of the subject. Each subject participated in two acquisition sessions (i.e., 198 practice trials) and was tested for learning on several different retention and transfer tests. In Experiment 2, a control group was added that received no acquisition phase. Results of both experiments showed a typical contextual interference effect, with depressed scores by the random groups during acquisition but significantly better scores than the blocked groups on several retention and transfer tests. Certain characteristics of the tests were found to influence the demonstration of the practice schedule effects. These results were consistent with predictions from Magill and Hall (1990) that the learning benefits of contextual interference are more likely to occur when skill variations are from different classes of movement and that the amount of variability in practice is more influential when the to-be-learned tasks are parameter modifications of the same generalized motor program.     

Intra-Limb Specificity of Motor Response Consistency

Two separate experiment using motor responses evaluated the specificity vs. generality of response consistency when the various tasks used the same limb for response. In Exp. I four similar tasks requiring rapid right arm movement were defined and, in Exp. II, Ss had to “hit” a moving target with either a maximal or moderately fast right hand movement. Although the mean intercorrelations among tasks were generally moderate to low (mean r = .85 and .30, respectively for Exp. I and II) the intercorrelations using response consistency scores (the SD of S’s responses about his own mean) were lower for Exp. I (mean r = .54) and similar for Exp. II (mean r = .30). These findings provided little support for a notion of a general within-limb factor of motor response consistency.     

Reductive and Emergent Views on Motor Learning in Rehabilitation Practice

To allow different views on motor learning to inform rehabilitation research, the authors aimed to explicate a frequently missed yet fundamental difference in starting point of such views. By considering how rehabilitation in practice answers the question of what parts an activity consists of, reductive and emergent approaches to motor learning are identified and traced throughout rehabilitation practice. The authors show that when a task is cut up along reductive dimensions while also apparently relying on emergent components, this unequally favors the reductive approach and acts to limit the views on motor learning available. By showing the approaches in practice, the authors hope to inspire an awareness that brings both approaches the opportunity to independently inform research so that new theories and practices can proliferate.     

The Effects of Practice Trials and Prior Learning on Motor Memory

The effects of prior positions (PL), practice reinforcements of the criterion distance (CT), and retention intervals on proactive interference (PI) in a 20-cm. linear positioning task were examined. Independent treatment groups had either 0, 3, or 5 PL, with 1, 3, or 10 CT, and a 5-, 15-, or 50-sec. retention interval. Only absolute error scores at recall indicated PI. This forgetting occurred only under the highly restricted conditions of 5 PL and 1 CT after 15-and 50-sec. retention intervals. Since 0 PL groups showed no differences in recall over levels of retention intervals, PI alone apparently caused the forgetting.     

The Learning Portfolio: Reflective Practice for Improving Student Learning

Books reviewed: Zubizarreta, John, The Learning Portfolio: Reflective Practice for Improving Student Learning
Reviewed by Sandra Lee Dixon
University of Denver     

Molecular Mechanisms Associated with the Benefits of Variable Practice in Motor Learning

Abstract

Variable practice promotes a higher level of motor learning than constant practice. The glutamate receptors, n-methyl-d-aspartate (NMDA) and alfa-amino-3-hydroxy-5-methyl-4-isoxazolepropionic (AMPA), have been associated with the changes in motor cortex that occur throughout the process of motor learning. Considering that, it is possible that variable practice is more associated with the NMDA and AMPA receptors than constant practice. This study aimed ao investigating the association between the glutamate receptors, NMDA and AMPA, and constant and variable practice schedules. Seventy-eight male mice practiced the rotarod task in a constant or variable scheduling, in two consecutive days (acquisition phase). Learning tests were performed 24?h and 10?days after the end of the acquisition phase. Variable practice was more associated with the NMDA receptor and had a greater AMPA receptor expression than constant practice. The results suggest that the benefits of variable practice are result of both the greater dependency on the NMDA receptor and the greater AMPA receptor expression.     

Dyad Practice Impacts Self-Directed Practice Behaviors and Motor Learning Outcomes in a Contextual Interference Paradigm

We studied dyad practice to determine whether and how alternating practice blocks with a partner impacts self-directed practice scheduling, learning, and perceptions of practice. Participants were assigned to be Partner 1 (P1) or 2 (P2). P1s had a blocked, random, or self-directed schedule, while all P2s self-directed practice of 3, differently-timed keystroke-sequences. P2s showed both own error-dependent practice (switching sequences following better performance) and partner-dependent practice, with the partner's schedule impacting sequence selection and switching frequency. A partner's schedule also impacted learning. Random practice resulted in better timing accuracy than blocked practice for both partners in an immediate and delayed retention test. These data give evidence that self-directed practice behaviors and learning outcomes are modulated by a partner's practice schedule.     

感知运动经验在心理时间线形成中的作用—来自盲生的证据

本研究考察视觉和读写习惯有关的感知运动经验是如何影响心理时间形成的。实验1和实验2分别采用一天内和一生中的词语或短句,以小学三年级的普生和盲生为被试,结果发现不论是短的还是长的时间,普生对早的刺激按左键,晚的刺激按右键反应更快,而盲生未出现早左晚右的心理时间线。实验3和实验4分别以短时间和长时间范围的时间词为材料,以初一盲生和普生为被试,结果发现普生和盲生都是对过去的时间按左键,未来的时间按右键反应快;而且在长的时间范围内,盲生的反应时长于普生。结果表明视觉是心理时间线的基础,阅读经验在盲生心理时间线的形成中起着关键作用。     

Transfer of Motor Learning Engages Specific Neural Substrates During Motor Memory Consolidation Dependent on the Practice Structure

The authors investigated how brain activity during motor-memory consolidation contributes to transfer of learning to novel versions of a motor skill following distinct practice structures. They used 1 Hz repetitive Transcranial Magnetic Stimulation (rTMS) immediately after constant or variable practice of an arm movement skill to interfere with primary motor cortex (M1) or dorsolateral prefrontal cortex (DLPFC). The effect of interference was assessed through skill performance on two transfer targets: one within and one outside the range of practiced movement parameters for the variable practice group. For the control (no rTMS) group, variable practice benefited delayed transfer performance more than constant practice. The rTMS effect on delayed transfer performance differed for the two transfer targets. For the within-range target, rTMS interference had no significant affect on the delayed transfer after either practice structure. However, for the outside-range target, rTMS interference to DLPFC but not M1 attenuated delayed transfer benefit following variable practice. Additionally, for the outside-range target, rTMS interference to M1 but not DLPFC attenuated delayed transfer following constant practice. This suggests that variable practice may promote reliance on DLPFC for memory consolidation associated with outside-range transfer of learning, whereas constant practice may promote reliance on M1 for consolidation and long-term transfer.     

Augmented Kinematic Feedback for Motor Learning

Although the study of feedback about goal achievement (knowledge of results, KR) has been important for the development principles of augmented information feedback in simple skills, there is reason to question the generalizability of these findings to many common learning situations. A more appropriate type of information for skill learning appears to be augmented kinematic (or kinetic) feedback regarding the movement pattern. The experiments presented here extend recent findings about KR to a paradigm involving kinematic feedback. In Experiment 1, we examined how several kinds of temporal and spatial kinematic information supplement KR in learning. Spatial kinematic variables were more effective than temporal variables, as indicated by performance in a retention test without kinematic feedback. In Experiment 2, we manipulated the schedule of augmented kinematic feedback in a method that paralleled previous KR work. We contrasted averaged schedules of augmented feedback, in which information was given either after every trial or as averaged information after every set of five trials. On retention tests without kinematic feedback given 1 day and 1 week after acquisition, averaged schedules led to enhanced performance over an every-trial format. Together, these results begin to define the variables important in kinematic feedback, and suggest that this feedback may influence learning in ways parallel to KR.     

Individualized Challenge Point Practice as a Method to Aid Motor Sequence Learning

We conducted two studies to investigate if and how: (1) the rate of skill acquisition was related to motor performance at retention of a serial RT task (Study 1); and (2) whether rate of skill acquisition and baseline performance could be used to design schedules of practice related to contextual interference (CI) to enhance motor learning (Study 2). In Study 1, a slower rate of skill acquisition of repeating sequences in practice was related to faster response times at retention. Based on performance in Study 1, three levels of individualized CI were created for Study 2. Compared to low and moderate levels of CI, the higher CI practice condition led to faster response times in retention. We conclude that an individualized ‘challenge point’, which generates high CI enhances motor learning by optimizing challenge.     

A Review of the Evidence for a Biological Basis for Snake Fears in Humans

The Psychological Record - Three types of evidence are considered for the view that the propensity of humans to fear snakes is derived from our evolutionary history. It is argued that findings from...