Stimulus velocity effect in a complex interceptive task in right- and left-handers

Abstract

This study investigated stimulus velocity effect on manual asymmetry during planning and execution of a complex coincidence-anticipation task. Left- and right-handers were required to press six buttons sequentially in conjunction with visual stimulus provided by a coincidence-anticipation device. Results showed that (1) stimulus velocity affected timing response and timing accuracy only for right-handers, who responded faster but less accurately in the fast stimulus velocity, (2) manual asymmetries for both handedness groups revealed a left-hand advantage for initiating the movement, and a preferred-hand advantage for movement time. The preferred-hand advantage in timing accuracy was only observed in the fast stimulus velocity. These findings are discussed in the framework of the hemispheric functional lateralisation.     

Age-related changes in proprioception of the ankle complex across the lifespan

BackgroundAnkle complex proprioceptive ability, needed in active human movement, may change from childhood to elderly adulthood; however, its development across all life stages has remained unexamined. The aim of the present study was to investigate the across-the-lifespan trend for proprioceptive ability of the ankle complex during active ankle inversion movement.MethodsThe right ankles of 118 healthy right-handed participants in 6 groups were assessed: children (6–8 years old), adolescents (13–15 years old), young adults (18–25 years old), middle-aged adults (35–50 years old), old adults (60–74 years old), and very old adults (75–90 years old). While the participants were standing, their ankle complex proprioception was measured using the Active Movement Extent Discrimination Apparatus.ResultsThere was no significant interaction between the effects of age group and gender on ankle proprioceptive acuity (F (5, 106) = 0.593, p = 0.705, η²_p = 0.027). Simple main effects analysis showed that there was a significant main effect for age group (F (5, 106) = 22.521, p < 0.001, η²_p = 0.515) but no significant main effect for gender (F (1,106) = 2.283, p = 0.134, η²_p = 0.021) between the female (0.723 ± 0.092, mean ± SD) and the male (0.712 ± 0.083) participants. The age-group factor was associated with a significant linear downward trend in scores (F (1, 106) = 10.584, p = 0.002, η²_p = 0.091) and a strong quadratic trend component (F (1,106) = 100.701, p < 0.001, η²_p = 0.480), producing an asymmetric inverted-U function.ConclusionThe test method of the Active Movement Extent Discrimination Apparatus is sensitive to age differences in ankle complex proprioception. For proprioception of the ankle complex, young adults had significantly better scores than children, adolescents, old adults, and very old adults. The middle-aged group had levels of ankle proprioceptive acuity similar to those of the young adults. The scores for males and females were not significantly different. Examination of the range of the scores in each age group highlights the possible level that ankle complex movement proprioceptive rehabilitation can reach, especially for those 75–90 years of age.     

Distribution of practice in motor skill acquisition: different effects for discrete and continuous tasks

Research on the benefits of distributed practice for the acquisition and retention of motor skills has a long history. The majority of this research has involved skill acquisition of continuous tasks. However, there is some evidence to suggest that distribution of practice effects are quite different for discrete tasks than for continuous tasks. In the present study, we used a single task, formed discrete and continuous versions of the task, and examined how acquisition and retention were affected by the length of inter-trial interval. The basic task was a movement timing task that involved either one timing estimate per trial (the "discrete" version) or twenty successive estimates per trial (the "continuous" version). Separate groups of subjects learned one version of the task under either distributed (25 s inter-trial intervals) or massed (0.5 s inter-trial intervals) practice conditions. Both massed and distributed retention trials were performed on the same version of the task according to a double transfer design. The results confirmed the apparent disparity: Acquisition and retention were facilitated by distributed practice on the continuous task, but by massed practice on the discrete task. These results were discussed in terms of the role of the inter-trial interval in discrete and continuous tasks.     

Attentional focus effects on sprint start performance as a function of skill level

Abstract

Several researchers have demonstrated that an external focus of attention (about movement’s effects) during movement execution allowed better performances and learning of various motor tasks than an internal focus of attention (about movement itself). However, attentional focus effects have not been studied in tasks requiring explosive actions preceded by fast reaction time to a signal, such as a sprint start. We hypothesised that the beneficial effect of external focus of attention would be observed in the different stages of the sprint start (i.e. reaction time, block clearance and running) for both expert and novice sprinters. Novice and expert sprinters performed sprint starts followed by a 10 m sprint under three conditions: external focus instructions; internal focus instructions; and neutral instructions. The reaction time and the running time were significantly shorter in the external focus condition than in the internal focus condition, for both expert and novice participants. These results confirm the beneficial effect of an external focus of attention on the speed of movement execution. Moreover, they revealed that attentional focus influences movement preparation. Several hypotheses are proposed to account for these results, with reference to the processes that could be responsible for the observed effects.     

The influence of lower limb amputation level on the approach in the amputee long jump

In this study, we investigated the adjustments to posture, kinematic and temporal characteristics of performance made by lower limb amputees during the last few strides in preparation for long jump take-off. Six male unilateral trans-femoral and seven male unilateral trans-tibial amputees competing in a World Championships final were filmed in the sagittal plane using a 100-Hz digital video camera positioned so that the last three strides to take-off were visible. After digitizing using a nine-segment model, a range of kinematic variables were computed to define technique characteristics. Both the trans-femoral and trans-tibial athletes appeared to achieve their reduction in centre of mass during the flight phase between strides, and did so mainly by extending the flight time by increasing stride length, achieved by a greater flexion of the hip joint of the touch-down leg. The trans-tibial athletes appeared to adopt a technique similar to that previously reported for able-bodied athletes. They lowered their centre of mass most on their second last stride (-1.6% of body height compared with -1.4% on the last stride) and used a flexed knee at take-off on the last stride, but they were less able to control their downward velocity at touch-down (-0.4 m x s(-1)). Both this and their restricted approach speed (8.9 m x s(-1) at touch-down), rather than technique limitations, influenced their jump performance. The trans-femoral athletes lowered their centre of mass most on the last stride (-2.3% of body height compared with -1.6% on the second last stride) and, as they were unable to flex their prosthetic knee sufficiently, achieved this by abducting their prosthetic leg during the support phase, which led to a large downward velocity at touch-down (-0.6 m x s(-1)). This, combined with their slower approach velocity (7.1 m x s(-1) at touch-down), restricted their performance.     

Coordination as a function of skill level in the gymnastics longswing

The purpose of this study was to investigate the nature of inter-joint coordination at different levels of skilled performance to: (1) distinguish learners who were successful versus unsuccessful in terms of their task performance; (2) investigate the pathways of change during the learning of a new coordination pattern and (3) examine how the learner’s coordination patterns relate to those of experts in the longswing gymnastics skill. Continuous relative phase of hip and shoulder joint motions was examined for longswings performed by two groups of novices, successful (n = 4) and unsuccessful (n = 4) over five practice sessions, and two expert gymnasts. Principal component analysis showed that during longswing positions where least continuous relative phase variability occurred for expert gymnasts, high variability distinguished the successful from the unsuccessful novice group. Continuous relative phase profiles of successful novices became more out-of-phase over practice and less similar to the closely in-phase coupling of the expert gymnasts. Collectively, the findings support the proposition that at the level in inter-joint coordination a technique emerges that facilitates successful performance but is not more like an expert’s movement coordination. This finding questions the appropriateness of inferring development towards a “gold champion” movement coordination.     

The effects of task constraints on visual search behavior and decision-making skill in youth soccer players

We examined differences in visual search behaviors and decision-making skill across different microstates of offensive play in soccer using youth participants (13.0-15.8 years) varying in skill and experience. We used realistic film simulations of offensive play, movement-based response measures, and an eye movement registration technique. Playing experience, skill level, and the unique constraints of the task, expressed by the number of players and relative proportion of offensive and defensive players, determined both the observed search behavior and processing requirements imposed on players in dynamic offensive team simulations. Significant differences in performance were observed between players and nonplayers and across three groups of soccer players who differed in skill level. Implications for talent identification and development are considered.     

The effects of required amplitude and practice on frequency stability and efficiency in a cyclical task

From an ecological point of view, motor learning emerges from the interplay of constraints on action, which shape behaviour towards the optimal solution, and practice, conceived as an active exploration of the work-space, to search this optimal solution. In the experiment reported here, we studied this interplay for a cyclical task performed on a ski-simulator. Our aim was to assess the respective effects of amplitude and practice on frequency variability and efficiency. On the basis of previous empirical findings, amplitude was expected, beyond a critical value, to constrain and stabilize the frequency of the movement. Three groups of participants practised during four sessions at three different amplitudes (15, 22.5 and 30 cm). The results showed that participants moving at large amplitude displayed more stable and more consistent frequencies. Nevertheless, there was no interaction effect between target amplitude and practice. On the other hand, movement economy and harmonicity increased with practice, but were not affected by amplitude. Finally, the results of transfer tests showed that the effects of large amplitude on frequency variability were not resistant to a subsequent decrease in target amplitude. These results suggest that constraints and practice act independently on motor behaviour, and that a high constraint could be detrimental to the development of effective search strategies.     

Perception and action in golf putting: skill differences reflect calibration

We assessed how golfers cope with the commonly observed systematic overshoot errors in the perception of the direction between the ball and the hole. Experiments 1 and 2, in which participants were required to rotate a pointer such that it pointed to the center of the hole, showed that errors in perceived direction (in degrees of deviation from the perfect aiming line) are destroyed when the head is constrained to move within a plane perpendicular to the green. Experiment 3 compared the errors in perceived direction and putting errors of novice and skilled players. Unlike the perceived direction, putting accuracy (in degrees of deviation from the perfect aiming line) was not affected by head position. Novices did show a rightward putting error, while skilled players did not. We argue that the skill-related differences in putting accuracy reflect a process of recalibration. Implications for aiming in golf are discussed.     

Dual-task assessment of a sporting skill: influence of task complexity and relationship with competitive performances

Abstract

We investigated the effect of increases in task complexity on the dual-task draw-and-pass performance of professional rugby league players. Moreover, we determined the relationship between dual-task draw-and-pass proficiency measured in isolation and draw-and-pass performances as they occurred in actual competitive matches. In Study 1, 12 rugby league players performed 2-on-1 and 3-on-2 attacking drills under single (primary skill) and dual-task (primary skill performed in conjunction with secondary-task) conditions. Reductions in draw-and-pass performance occurred when task complexity was increased from the 2-on-1 to the 3-on-2 situation. In Study 2, 58 rugby league players undertook the dual-task draw-and-pass assessment. Players then competed in National Rugby League matches with video footage coded for the number of tries scored and the activities that led to the try. A total of 303 tries were scored with 150 (49.5%) tries scored from a draw-and-pass situation. Significant associations were detected between 2-on-1 dual-task draw-and-pass performance in the isolated test condition and draw-and-pass performances in competition. These studies provide evidence of (i) the greater attentional demands of the skill of drawing-and-passing in elite team sport athletes when more players are involved and (ii) the practical utility of off-field dual-task testing in supplying information predictive of skills performance in competition.     

Learning a coordination skill: interactive effects of instruction and feedback

Information prior to and during the acquisition of a continuous bimanual task was manipulated. Participants practiced a difficult coordination pattern, which produced circular shapes on the computer, when they moved their arms correctly. Four groups were examined, which differed in the type and amount of information provided. Either limb or circle feedback was provided in the presence or absence of instructions detailing how to move the limbs. Circle feedback facilitated learning relative to the limb feedback in which the explicit displacements of the limbs was displayed. Under circle feedback conditions, instructions hindered acquisition. Little instructional effects were observed under limb feedback conditions, despite the prediction that instructions would benefit learning when the feedback was more compatible. Findings are discussed in relation to the complexity of the feedback and processing demands.     

Relationship between decision-making self-efficacy, task self-efficacy, and the performance of a sport skill

The purpose of this study was to examine the relationships between decision-making self-efficacy and task self-efficacy and subsequent decision-making and task performance. Sixty undergraduate students (30 males, 30 females) participated in this study, which involved infield defensive plays in softball. The physical task required participants to throw a ball at a target. The decision-making task required participants to watch video scenes depicting different infield defensive situations and decide where to throw the ball in each situation. Both tasks used manipulated failure. Self-efficacy was assessed before performance. Strength of decision-making and task self-efficacy predicted physical performance, but not decision-making performance.     

Relationship between decision-making self-efficacy,task self-efficacy,and the performance of a sport skill

Abstract

The purpose of this study was to examine the relationships between decision-making self-efficacy and task self-efficacy and subsequent decision-making and task performance. Sixty undergraduate students (30 males, 30 females) participated in this study, which involved infield defensive plays in softball. The physical task required participants to throw a ball at a target. The decision-making task required participants to watch video scenes depicting different infield defensive situations and decide where to throw the ball in each situation. Both tasks used manipulated failure. Self-efficacy was assessed before performance. Strength of decision-making and task self-efficacy predicted physical performance, but not decision-making performance.     

Decision training: the effects of complex instruction, variable practice and reduced delayed feedback on the acquisition and transfer of a motor skill.

Novice, intermediate and advanced baseball hitters followed a 7-week training programme, in which they received either behavioural training or decision training. Participants in the behavioural training group received simple-to-complex instruction, variable practice and an abundance of feedback throughout the acquisition period; the decision training group received complex instruction, variable practice and reduced delayed feedback. As predicted, the intermediate and advanced hitters who received decision training hit at a lower level (%) during acquisition but at a higher level during a transfer test in week 7. Novices in the behavioural training group were better than novices in the decision training group over both acquisition and transfer trials.     

Decision training: The effects of complex instruction,variable practice and reduced delayed feedback on the acquisition and transfer of a motor skill

Novice, intermediate and advanced baseball hitters followed a 7–week training programme, in which they received either behavioural training or decision training. Participants in the behavioural training group received simple-to-complex instruction, variable practice and an abundance of feedback throughout the acquisition period; the decision training group received complex instruction, variable practice and reduced delayed feedback. As predicted, the intermediate and advanced hitters who received decision training hit at a lower level (%) during acquisition but at a higher level during a transfer test in week 7. Novices in the behavioural training group were better than novices in the decision training group over both acquisition and transfer trials.     

Age-related differences in the control of spatial aiming movements.

The experiment was designed to (a) examine age-related differences in the control of aiming movements, and (b) determine the locus of slowing in movement execution of older adults. Fitts's (1954) index of difficulty (ID) was used to manipulate movement execution demands, and kinematics were used to examine the response characteristics. Twelve young and 12 older adults performed simple aiming movements 10 cm or 20 cm in amplitude to targets of 0.5 cm, 1.0 cm, or 2.0 cm in width, resulting in IDs ranging from 3.32 to 6.32. The results for both young and older subjects support the prediction that movement time (MT) increases as a function of ID and that older adults are significantly slower and more affected by increases in ID than the young adults. Velocity and acceleration profiles of the older adults' movements displayed very different response characteristics than those of the young adults. The results suggest that older adults emphasize accuracy of response and are concerned with the latter phase of the movement in order to contact a target accurately.     

多模态功能训练对女大学生功能性踝关节不稳患者下肢肌力、本体感觉和动态平衡能力的影响

目的:探讨多模态功能训练对功能性踝关节不稳(Functional ankle instability,FAI)患者肌肉力量、本体感觉功能和动态平衡能力的影响。方法:45名FAI患者随机分为常规力量训练组(strengh training,ST组,n=22)和多模态功能训练组(multimodal function training,MFT组,n=23)。ST组常规力量训练,MFT组在常规力量力量训练的基础上增加本体感觉和姿势控制训练,康复训练共进行8周,2个训练周期。实验前后分别对2组实验对象患侧踝关节屈、伸、内翻和外翻肌群60°/s和180°/s等动向心收缩相对峰值力矩、本体感觉(踝关节屈、伸、内收和外翻运动感觉功能、腓骨肌反应时)和动态平衡能力(前方得分(A)、后内侧得分(PM)、后外侧得分(PL)和YBT-CS总得分)进行测试。结果:1)2组受试者患侧踝关节60°/s和180°/s等动向心踝关节肌群相对峰值力矩均显著大于实验前(P<0.05),且二者组间没有显著性差异(P>0.05);2)实验后,ST组本体感觉功能没有显著性改变(P>0.05),MFI组本体感觉各项指标均显著小于实验前(P<0.005,P<0.01,P<0.05),且均显著低于ST组(P<0.05);3)试验后,2组受试者动态平衡各指标均优于实验前(P<0.05,P<0.01),且MFI动态平衡各项指标均优于ST组(P>0.05)。结论:MFT康复训练能够显著改善FAI患者肌力、本体感觉和动态平衡能力,且效果更优于ST组。     

Coincidence timing of a tennis stroke: effects of age, skill level, gender, stimulus velocity, and attention demand

Participants (N = 162, ages 10-15 years) performed a tennis stroke in a coincidence-timing task. Major results were: (a) performance improved mainly between the ages of 10-13 years; (b) skill differences were reflected by variable error (VE); (c) boys were lower than girls for VE and absolute error; (d) high stimulus velocity was related to low VE and late responding. Results concerning response organization favored explanations based on ecological perspectives rather than information processingperspectives. However, it is premature to disregard the potential role of programming. The view is supported that a continuous process of coupling perceptual and motor responses coordinates control of response timing. These cognitive processes appear to be: (a) refined with practice; (b) sensitive to differences in age, skill, and gender; and (c) adaptable to changes in environmental demands.     

Part and whole practice: chunking and online control in the acquisition of a serial motor task

A four-component aiming movement was used to examine the relative effectiveness of part and whole practice. Following a pretest, participants were assigned to one of three practice groups. Participants in a "Whole" group practiced the four components together as a unit. A "No Overlap" group practiced the first two and last two components of the task, alternating every fifth trial. An "Overlap" group practiced the transition between the second and third components on every trial by alternating practice of the first three and last three components every five trials. Participants in all groups improved significantly from pretest to immediate posttest and maintained their performance over a 24-hr delay. Contrary to the "chunking hypothesis," participants in the No Overlap group improved as much as those in the other two groups. Kinematic data indicated that participants in all three groups learned to use response-produced feedback earlier in the individual movement trajectories. Moreover, participants appeared to acquire a general ability to make transitions between movement components rather than specific transitions. The results suggest that segmented or segmented "overlap" practice regimes may benefit learning movement sequences of short duration.