Throwing Task Research Articles

More than Meets the Eye: Investigating Imagery Type, Direction, and Outcome

The effects of imagery direction on self-efficacy and performance in a dart throwing task were examined. Two imagery types were investigated: skill-based cognitive specific (CS) and confidence-based motivational general-mastery (MG-M). Seventy-five novice dart throwers were randomly allocated to one of three conditions: (a) facilitative imagery, (b) debilitative imagery, or (c) control. After 2 imagery interventions, the debilitative imagery group rated their self-efficacy significantly lower than the facilitative group and performed significantly worse than either the facilitative group or the control group. Efficacy ratings remained constant across trials for the facilitative group, but decreased significantly for both the control group and the debilitative group. Performance remained constant for the facilitative and the control groups but decreased significantly for the debilitative group. Similar to Short et al. (2002), our results indicate that both CS and MG-M imagery can affect self-efficacy and performance.

Immediate and Delayed Bilateral Transfer of Throwing Accuracy in Male and Female Children

In the present study, an attempt was made to examine the nature and persistence of bilateral transfer of a throwing skill for a large sample of male and female children. One hundred sixty children ages 6, 8, 10, and 12 years were randomly assigned to either an experimental or control group with an equal number of boys and girls in each group. The experiment lasted 2 days and consisted of a pretest, a practice phase, an immediate transfer test, and a delayed transfer test. On the pretest, each participant performed 10 trials of a novel one-hand throwing task. Following the pretest, participants in the experimental group practiced the skill with the hand opposite the one used during the pretest until they had successfully reached a designated criterion for their age. Participants in the control group performed a balancing activity. Following the practice phase, all participants performed immediate (10 min later) and delayed (24 hr later) transfer tests under the same conditions as the pretest. The results revealed no group differences on the pretest but significantly higher throwing accuracy for the experimental group than the control group on both transfer tests. In addition, boys' throwing accuracy was significantly superior to the girls. It was concluded that bilateral transfer of throwing accuracy can be both a temporary and relatively persistent phenomenon for children and the superior throwing accuracy for boys is consistent with similar gender differences in throwing distance and throwing velocity (Thomas & French, 1985).

Learning a throwing task is associated with differential changes in the use of motor abundance

This study sought to characterize changes in the synergy of joint motions related to learning a Frisbee throwing task and, in particular, how the use of abundant solutions to joint coordination changed during the course of learning for successful performance. The latter information was helpful in determining the relative importance of different performance-related variables (PVs) to performance improvement. Following a pre-test, the main experiment consisted of six subjects practicing a Frisbee throw to a laterally-placed target for five days, 150 throws per day, followed by a post-test. A subgroup of three subjects continued to practice for an extended period of extensive practice amounting to 1800-2700 additional throws each, followed by a second post-test. Motor abundance was addressed through the uncontrolled manifold approach (UCM), which was used to partition the variance of joint configurations into two components with respect to relevant PVs, one component leading to a consistent value of the PV across repetitions, and a reflection of motor abundance, and a second component resulting in unstable values of the relevant PV. The method was used to test hypotheses about the relative importance of controlling the PVs that have an impact on successful task performance: movement extent, movement direction, hand path velocity, and the hand's orientation to the target. In addition, the amount of self-motion, or apparently extraneous joint motion having no effect on the hand's motion, compared to joint motion that does affect the hand's motion, was determined. After a week of practice, all subjects showed improvement in terms of targeting accuracy. Hand movement variability also decreased with practice and this was associated with a decrease in overall joint configuration variance. This trend continued to a greater extent in the three subjects who participated in extended practice. Although the component of joint configuration variance that was consistent with a stable value of all PVs was typically substantially higher than variance leading to unstable values of those PVs, both components decreased with practice. However, the decrease in joint configuration variance reflecting motor abundance was less than the other variance component only in relation to control of movement direction and the hand's orientation to the target. These results indicate that improvement of throwing performance in this experiment was more related to improved stabilization of movement direction and to the hand's orientation to the target than to movement extent and hand velocity. Nonetheless, the relative values of the two joint variance components were such that the instantaneous value of both hand path velocity and movement extent were stabilized throughout the experiment and showed a consistent compensatory relationship at the time of Frisbee release, despite not changing with practice. Finally, the amount of self-motion increased significantly with practice, possibly reflecting better compensation for perturbations due to the limb's dynamics. The results are consistent with other studies, suggesting the need to reevaluate Bernstein's hypothesis of freeing and freezing DOFs with learning.

Normal prism adaptation but reduced after-effect in basal ganglia disorders using a throwing task.

Prism adaptation is a form of visuomotor learning in which the visual and motor systems need to be adjusted because a visual perturbation is produced by horizontally displacing prisms. Despite being known for over two centuries, the neuronal substrates of this phenomenon are not yet completely understood. In this article the possible role of the basal ganglia in this kind of learning was analysed through a study of Huntington's and Parkinson's disease patients. A throwing technique requiring the use of open loop feedback was used. The variables analysed were visuomotor performance, adaptation rate and magnitude, and the after-effect. The results clearly showed that both Huntington's and Parkinson's disease groups learned at the same rate as control subjects. In addition, despite having a disturbed visuomotor performance, both experimental groups showed the same adaptation magnitude as the control group. Finally, the after-effect, which is measured after removing the prisms, is reduced in both patients groups. This reduction leads to a disruption in the normal adaptation-after-effect correlation found in normal volunteers. These results suggest that basal ganglia are not involved in this type of open-looped visuomotor learning. The large number of patients studied as well as the similarity of the findings between both populations support this hypothesis. By contrast, there is an impairment in the after-effect on both basal ganglia patient populations. This impairment may be the result of the deterioration of the perceptual recalibration process involved in visuomotor learning.

Influence of instruction on velocity and accuracy of overarm throwing.

This study investigated the influence of instruction on the ball velocity and accuracy of a goal-directed overarm throw. 9 experienced Norwegian male team handball players executed a throwing task randomly seven times under 5 different instructions varying from emphasizing speed to accuracy. When instructions increasingly emphasized accuracy, velocity decreased. However, accuracy did not improve when subjects were instructed to focus on it. A possible explanation for this finding could lie in the specific subject group. The subjects were highly experienced team handball players with an average of 12 years in the sport. Thus, the accuracy they demonstrated at high velocity might actually be already extremely high and difficult to improve upon when reducing throwing velocity. Further, the velocity of throwing when instruction emphasized accuracy was approximately 85% of the maximal velocity, indicating that experienced team handball players are trained to throw accurately at relatively high velocity.

PRACTICE SCHEDULE AND ACQUISITION, RETENTION, AND TRANSFER OF A THROWING TASK IN 6-YR.-OLD CHILDREN

PRACTICE SCHEDULE AND ACQUISITION, RETENTION, AND TRANSFER OF A THROWING TASK IN 6-YR.-OLD CHILDREN

ボール投げ課題における要約フィードバックと結果についての自己評価の効果

ボール投げ課題における要約フィードバックと結果についての自己評価の効果

The Biomechanics of an Overarm Throwing Task: a Simulation Model Examination of Optimal Timing of Muscle Activations

A series of overarm throws, constrained to the parasagittal plane, were simulated using a muscle model actuated two-segment model representing the forearm and hand plus projectile. The parameters defining the modeled muscles and the anthropometry of the two-segment models were specific to the two young male subjects. All simulations commenced from a position of full elbow flexion and full wrist extension. The study was designed to elucidate the optimal inter-muscular coordination strategies for throwing projectiles to achieve maximum range, as well as maximum projectile kinetic energy for a variety of projectile masses. A proximal to distal (PD) sequence of muscle activations was seen in many of the simulated throws but not all. Under certain conditions moment reversal produced a longer throw and greater projectile energy, and deactivation of the muscles resulted in increased projectile energy. Therefore, simple timing of muscle activation does not fully describe the patterns of muscle recruitment which can produce optimal throws. The models of the two subjects required different timings of muscle activations, and for some of the tasks used different coordination patterns. Optimal strategies were found to vary with the mass of the projectile, the anthropometry and the muscle characteristics of the subjects modeled. The tasks examined were relatively simple, but basic rules for coordinating these tasks were not evident.

Benefits of providing cognitive performance strategies to novice performers learning a complex motor skill.

Verbal reports were collected from experienced performers during acquisition trials of a novel throwing task and summarized as cognitive performance strategies. These strategies were incorporated in the practice regimen of 8 novices with no sport experience who learned the same task. A control group of 8 novices practiced the task without the experts' cognitive performance strategies. The performance of the novices who used the strategies was similar to that of the experts and significantly better than the performance of the control novices.

The cognitive neuropsychology of sex hormones in men and women

In this study, we examined sex differences in performance on a variety of cognitive tasks. Performance was correlated with estradiol and testosterone levels in both men and women in order to examine whether hormone levels are related to performance on tasks that do and do not show sex differences. Men showed an advantage in performance on tests of spatial cognition (block design and card rotation) as well as a dart throwing task that requires both motor skills and spatial cognition. Sex differences were not found for measures of verbal and nonverbal memory, verbal fluency, or fine motor performance. Hormone levels were related to performance on tasks that showed sex differences as well as those that did not. Estradiol, but not testosterone, was related to block design in women but not men. Women with higher estradiol levels showed better performance than women with lower estradiol levels. No relations between card rotation and hormone levels were found. Performance on the two spatial cognitive measures were related to each other in women, but not men, suggesting that men may use different processes than women to accomplish these tasks. Performance on the dart throwing task was not consistently related to the spatial cognitive measures in either men or women. Positive relations that will require confirmation were found between estradiol and spatial recall, and between testosterone and verbal recall, in men. In general, both men and women showed a negative relation between both estradiol and testosterone and dart throwing performance. These results do not support the notion that sex differences will necessarily predict the direction of the relation (positive or negative) between estrogen or testosterone and behavior in adulthood.

Gender Differences in Intercepting a Moving Target by Using a Throw or Button Press

Humans are a throwing species just as much as a talking species (Calvin, 1982), but preadaptations for throwing remain largely unexplored. The ability of undergraduate students (N = 165) to intercept a stimulus with a thrown object was determined for 10 stimulus speeds, ranging from 2 to 5 m/s. The inclusion of a condition in which the moving stimulus was intercepted via button press allowed the role of the perceptual aspect of velocity estimation to be evaluated separately from the act of throwing. Gender differences were observed in both the button and the throwing intercept tasks: The men had smaller timing errors and higher accuracy than the women. Contrary to expectations, the male and female patterns of intercept errors as a function of stimulus speed were more similar in the throwing task than in the button intercept task.

Contextual interference effects in learning novel motor skills.

The present study investigated the generalizability of contextual interference effects by extending previous laboratory and field research to novel movements controlled by different motor programs. 30 men and 33 women learned novel throwing and kicking tasks, practicing with blocked, serial, or random schedules. The subjects practiced the tasks four days a week for two weeks and then were given a postest. One week later subjects were given a retention test. Significant improvements in performance were found for all groups for both tasks; however, a significant effect for practice condition was found only for the throwing task during retention, for which the random practice schedule led to better learning than the blocked and the serial practice. These findings suggest that the blocked, serial, and random practice methods could be effectively used for tasks controlled by different motor programs but must be practiced in the same teaching session, without expecting one to be more effective in learning than any other.

Problems with Identification of Children Who Are Physically Awkward Using the TOMI

This study investigated whether the TOMI (Stott, Moyes, & Henderson, 1984), a motor skills test recommended for the identification of children who are physically awkward (Sugden, 1985; Wall, Reid, & Paton, 1990), contains biased items. Findings of a study by Causgrove and Watkinson (1993) indicated that an unexpectedly high proportion of girls from Grades 3 to 6 were identified as physically awkward, and the authors suggested that the TOMI may be biased in favor of boys. In the present study, this suggestion was investigated through comparison of performances of TOMI subtest items by boys and girls from Grades 1 to 6. Chi-square analyses on each of the eight test items revealed significant performance differences between boys and girls on the two ball skills tasks of catching and throwing (p < .0001) at Age Bands 3 and 4; a significantly greater proportion of boys than girls age 9 to 12 years passed the catching and throwing tasks. A significant performance difference was also found on the tracing task at Age Band 1, with more girls passing tracing than boys. Implications for future research requiring the identification of children who are physically awkward are discussed.

Use of Imagery Practice for Improving a Motor Skill

The purpose of this study was to examine the role of imagery practice as supplementary practice in the performance of a throwing task. A secondary purpose was to ascertain if different cognitive demands of a motor task affected the use of this supplementary practice. Forty adolescents with mild mental retardation were randomly assigned to the following groups: low cognitive loading-physical practice, low cognitive loading-imagery and physical practice, high cognitive loading-physical practice, high cognitive loading-imagery and physical practice. Subjects engaged in seven practice sessions during which performance scores of a throwing task were recorded. Groups supplemented with imagery practice were superior in performance to nonimagery groups. A higher cognitive loading of the task did not enhance the use of this type of supplementary practice more than a lower loading. The results of this study reflect the efficacy of imagery practice as a means to improve motor performance of students with mild mental retardation.

Contextual Interference Effects in the Acquisition and Retention of Motor Tasks by Individuals with Mild Mental Handicaps

The effects of contextual interference on motor skill acquisition and retention were examined in 24 subjects (mean age 13.9 years) with mild mental retardation and 24 chronologically age-matched subjects (mean age 13.11 years) with no disabilities. Subjects from each group were assigned randomly to either a blocked or a random practice schedule. All subjects performed 15 practice trials for each of three different beanbag throwing tasks, 45 trials total. Following a 10-min filled retention interval, 2 trials of each throw (6 total) were performed in a random order by all subjects. Accuracy scores were measured as absolute error from the target. The data revealed a significant interaction between ability groups and practice schedule. Post hoc analyses revealed that the retention scores of the mildly mentally handicapped subjects practicing under blocked conditions were significantly less accurate than scores of any of the other three acquisition groups. Significant effects in variable error retention scores indicated that subjects in the random practice condition performed more consistently than subjects in the blocked condition.

The role of sensory information in the guidance of voluntary movement: reflections on a symposium held at the 22nd annual meeting of the Society for Neuroscience.

This article reviews a symposium on the sensory control of movement held at the 22nd annual meeting of the Society for Neuroscience. Four speakers addressed a large audience on the proposition that "one can only control what one senses." Charles Vierck supported the notion with a description of the severe motor deficits caused by lesions of the spinal dorsal columns (DCs) in monkeys. In the discussion of Vierck's presentation, Robert Forget described the difficulties experienced by deafferented patients in tasks of daily life. Next, John Brooke showed that sensorimotor transformations vary greatly with task, anticipation, and uncertainty. In light of this, he questioned the simplifications inherent in servo and equilibrium-point theories of motor control. Paul Cordo then showed that in a rapid throwing task, proprioceptive information is used to control the moment of release (contradicting the idea that sensory feedback is too delayed for ballistic movements). Dick Burgess, like Brooke, criticized equilibrium-point models; he argued that a subject's sense of effort is a measure of the internal motor command, which should correspond to specific equilibrium points. However, his experimental data were inconsistent with this interpretation. He suggested instead that motor output is adjusted by comparing incoming afferent information to an expected "afferent template." Anatol Feldman and Mark Latash disagreed, saying that a constant sense of effort does not imply a constant equilibrium-point command. The equilibrium-point debate was not resolved, but the symposium ended with a consensus that in most motor tasks, one can control only what one senses.

The performance of goal-directed movements I: The relationship between limb kinematics and task accuracy during a dart throwing task

The performance of goal-directed movements I: The relationship between limb kinematics and task accuracy during a dart throwing task

The performance of goal-directed movements: The relationship between limb kinematics and task accuracy during a dart throwing task

The performance of goal-directed movements: The relationship between limb kinematics and task accuracy during a dart throwing task

The effect of type of practice on motor learning in children

AbstractThe present investigation was concerned with the variability‐of‐practice hypothesis of Schmidt's schema theory of motor learning; i. e. it was sought to determine if there is an optimal way to structure the variable practice session with regard to schema formation. Furthermore, children's motor recognition (movement evaluation) was examined, in addition to recall (movement production), since apparently no such studies had been done within the context of schema theory before. Eighty‐eight girls and boys with a mean age of 11.3 years were tested on a throwing task. Three groups of subjects practised under variable conditions (different target distances and weights) that differed with regard to contextual interference and sequential organization of task variations; another group received constant throwing practice. Following practice trials with knowledge of results, the four treatment groups and a control group without prior practice were required to produce and evaluate a novel response (novel target distance and weight) without vision and knowledge of results. The results supported the variability‐of‐practice hypothesis, in that variable practice in general facilitated recall and recognition on the novel task. Furthermore, variable practice with the highest level of contextual interference (random order of tasks) produced most effective transfer performance, suggesting that the structure of the variable‐practice session in fact plays a role with regard to the effectiveness of motor schema development. Contrary to the ‘organization hypothesis’ (Gentile and Nacson, 1976) a hierarchical organization of movement variations was not more beneficial to schema formation than random practice.

Effects of model's skill level and model's knowledge of results on the performance of a dart throwing task

The experiment was designed to examine how the effects of the model's skill level and the model's knowledge of results affected performance of an aiming task. Thirty novice, female dart throwers were randomly assigned to six conditions: four groups to complete a 2×2 factorial of model's skill level (skilled vs. unskilled) and model's knowledge of results (KR vs. No-KR), plus two control groups: one to control for the number of prior task experiences and one to control for the number of practice trials. Practice resulted in more accurate (AE) initial performance than did merely observing a model, and observing a model was not better than receiving no prior task experiences. Subjects observing the skilled model required the model's knowledge of results to perform with the same degree of accuracy (AE) as that obtained from observing the unskilled model. Observing the unskilled model resulted in a more consistent (VE) performance throughout practice. There were no performance changes over a 24-hour retention interval. These findings provide preliminary support for the contention that a correct model may not be the best for creating an accurate conceptual representation; and that the effects of observing a model are short lived.