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1.
This study shows that the difference in appearance between two types of computer generated real time visual information namely, cursor and trace feedback, becomes visible in the execution of aimed stylus movements. Movement execution was scrutinized by division into four relevant subsequent constituents on the basis of key kinematic events. As expected, the final section of a movement took more time and showed a larger number of adjustments in the cursor condition. Instead, the influence of trace feedback on movement execution became discernible in earlier sections of movement execution. When a combination of feedback types was employed, trace feedback seemed to dominate the impact on execution. Discussion focuses on the contribution of the present study to understanding the impact of specific features inherent to types of real time visual feedback, and the relevance of the present study's result to future research.  相似文献   

2.
The purpose of this study was to investigate what types of visual cues may contribute to improving movement accuracy in a pointing task, and to determine in what kind of control processes these cues are involved. During the experiment, subjects had to point their finger at visual targets as accurately as possible making rapid movements. Subjects were required to perform a movement with an amplitude of 40 cm within a series of times ranging from 110 to 270 msec. Five visual feedback conditions were applied: no feedback (NF), dynamic ongoing feedback on the complete hand trajectory (CF), static error feedback on the movement end-point (EF), and two partial feedback conditions in which dynamic feedback was available from either the initial (IF) or the terminal (TF) part of the trajectory. The results showed that under the NF and IF conditions accuracy was lowest; constant error was not speed-dependent, whereas dispersion increased with movement speed. Accuracy was highest under the CF and TF conditions and was speed-dependent, as shown by both constant error and dispersion. Under the EF condition, the accuracy level was intermediate, and was also speed-dependent. The time course of performance during the series was analyzed by comparing the mean error of the first and the last five-trial blocks in the series under the three feedback conditions resulting in accuracy improvement and speed-dependence (CF, TF and EF). The block effect was significant overall, with the last block showing greatest accuracy. The block effect was found to be significant for rapid movements only under the CF and TF conditions (with a Block × Speed interaction under the CF condition), and for all movement speeds under the EF condition. But the feedback and speed effects turned out to be significant for each block. The results are discussed in terms of the interchange between ‘corrected’ ongoing responses vs ‘amended’ delayed responses within the motor regulatory processes, the preponderance of one or the other type of response being dependent on feedback availability and movement speed.  相似文献   

3.
The courts in England and Wales have repeatedly claimed that they occupy a position of religious neutrality when faced with a case involving parties from two differing religions. While this assertion may well be true, when established, traditional religions are involved, it does not appear to be so clear cut, when one of the religions could be described as a ‘new religious movement’ or an ‘alternative religion’. Perhaps the most telling area of law in which to examine the courts’ alleged neutrality is in custody disputes in family law, as it is in these cases that the religious practices of the parents have sometimes become a factor in the case and judges have been more likely to express their opinion of such religious practices. This article analyses the approach of judges to such disputes and demonstrates that the judges tend to maintain a bias towards Judaeo-Christian morality.  相似文献   

4.
This paper describes an innovative investigation of commonsense conceptions of emotion using a two-person game where one player asked questions intended to determine the nature of an emotional state imagined by the other player. All questions used by players were then sorted into categories by expert judges. Based on cluster analysis, questions were categorized as relating to ‘causes’, ‘characteristics’, and ‘consequences’ of emotional states. Potential advantages and applications of this technique are discussed.  相似文献   

5.
Providing choices, i.e., autonomy, to athletes during practice increases intrinsic motivation and positively influences the motor learning process. The effects of autonomy on the timing of feedback (self-controlled timing of feedback) when optimizing the movement execution of sidestep cutting (SSC), a task that is highly related with ACL injury risk, are unknown. The aim of this study was to investigate the effect of self-controlled timing of video and EF-feedback on movement execution of SSC in team sport athletes. Thirty healthy ball team sport athletes (22.9 ± 1.7 years, 185.5 ± 7.2 cm, 79.3 ± 9.2 kg) were recruited from local sports clubs. Participants were alternately assigned to the self-control (SC) or the yoked (YK) group based on arrival and performed five anticipated and five unanticipated 45° SSC trials as pre-, immediate-post and one-week retention test. Movement execution was measured with the Cutting Movement Assessment Score (CMAS). Training consisted of three randomized 45° SSC conditions: one anticipated and two unanticipated conditions. All participants received expert video instructions and were instructed to ‘try to do your best in copying the movement of the expert’. The SC group was allowed to request feedback whenever they wanted during training. The feedback consisted of 1) CMAS score, 2) posterior and sagittal videos of the last trial and 3) an external focus verbal cue on how to improve their execution. The participants were told to lower their score and they knew the lower the score, the better. The YK group received feedback after the same trial on which their matched participant in the SC group had requested feedback. Data of twenty-two participants (50% in SC group) was analyzed. Pre-test and training CMAS scores between groups were equal (p > 0.05). In the anticipated condition, the SC group (1.7 ± 0.9) had better CMAS scores than the YK group (2.4 ± 1.1) at the retention test (p < 0.001). Additionally, in the anticipated condition, the SC group showed improved movement execution during immediate-post (2.0 ± 1.1) compared to pre-test (3.0 ± 1.0), which was maintained during retention (p < 0.001). The YK group also improved in the anticipated condition during immediate-post (1.8 ± 1.1) compared to pre-test (2.6 ± 1.0) (p < 0.001) but showed decreased movement execution during retention compared to immediate-post test (p = 0.001). In conclusion, self-controlled timing of feedback resulted in better learning and greater improvements in movement execution compared to the control group in the anticipated condition. Self-controlled timing of feedback seems beneficial in optimizing movement execution in SSC and is advised to be implemented in ACL injury prevention programs.  相似文献   

6.
In the present study, the influence of simultaneous action execution on motor priming was investigated during movement observation using a simple-reaction task. Although previous studies have reported various effects of priming on motor performance, it has not yet been clarified how an additional source conveying kinetic information would modulate the priming effects. In the experiment, participants were asked to respond to an auditory cue by flexing their wrist while observing a line movement, which was slowly swinging like an inverted pendulum. In addition to the observation of line movement, the participants executed wrist flexion-extension actions synchronizing with line movement. The hand involved in pre-response wrist action varied with the priming condition: no movement execution (observation only), contralateral hand, and ipsilateral hand. In the contralateral condition, the stimulus-response congruency of movement direction was conflicted depending on the frame of reference (visual vs. anatomical coordinates). We found that all three priming conditions produced the compatibility effect, and the effect size did not differ between them. Importantly, in the contralateral condition, participants responded faster when the direction of line movement was congruent with the response movement in the anatomical coordinates. That is, the reaction time was shorter when pre-response action execution was in the flexion phase, even though the direction of observed movement and the response action were incongruent from the participants’ view. These results suggest that kinetic information has a great contribution to the motor priming system, which can reverse the vision-based compatibility effect.  相似文献   

7.
The purpose of this study was to investigate the role of propriomuscular feedback in the control of pluriarticular pointing movements, performed without visual feedback toward visual targets. The proprioceptive inputs were distorted during movements by applying vibration to the distal tendon of the biceps muscle. Various movement and vibration durations were imposed. The results show that vibration affects the spatial outcome of the movements. The effects of vibration were movement time-independent when the durations were shorter than 450 ms and became movement time-dependent with longer durations. Moreover, the effects of vibration became more marked when a short vibration was applied at the end rather than at the beginning of a slow movement. These studies suggest that at least two types of proprioceptive control loops may be involved in correcting this kind of movement, depending on the execution time. In slow movements, the final phase might be a privileged period for on-line, propriomuscular-based corrections. Lastly, it emerged that the regulation of a goal-directed movement on the basis of proprioceptive feedback processing can take place within at most 200 ms.  相似文献   

8.
Tablets are increasingly being used in schools for a variety of handwriting tasks. Given that the control of handwriting relies on both visual and proprioceptive feedback, especially in younger writers, this raises the question of whether the texture of the tablet surface affects graphomotor execution. A series of recent studies found that when the smoothness of a tablet screen modifies proprioceptive feedback, the impact on graphomotor execution varies according to the level of the writer’s handwriting skills. However, as the writing on the screen remained visible in these studies, participants may have compensated for the decrease in proprioceptive feedback by relying more heavily on visual information. The aim of the present study was therefore to unravel the respective contributions of different types of sensory feedback during handwriting development and, consequently, the compensatory role of visual information when children and adults have to write on a tablet. To this end, we asked second and fifth graders and adult participants to write letters and pseudowords on a plastic board placed on top of a tablet screen. Participants wrote on either the smooth or the granular side of the plastic board (manipulation of surface friction), and with normal vision or behind a shield that hid the hand and handwriting from direct view (manipulation of vision). Kinematic parameters and legibility were recorded to assess handwriting performances. Results revealed a significant interaction between proprioceptive and visual feedback on letter size, pen speed and legibility, regardless of participants’ age. Furthermore, reducing the visual and proprioceptive feedback had a greater effect on the children’s handwriting performances than on those of adults. Overall, the present study provides new insight into the contribution of the different types of sensory feedback and their interaction with handwriting development. In addition, our results on the impact of tablet surface on graphomotor execution will serve as useful pointers for improving the design of this tool for children, such as increasing the degree of friction of the screen surface.  相似文献   

9.
《Human movement science》1986,5(2):185-206
This study tests the contributions of structural and transformational information in the perception of technical execution and aesthetic quality in gymnastics judging. A focal question was whether the quality of human movement usually called aesthetic belongs to some category different from mere transformations of position over time, i.e., kinematics. Qualified gymnastics judges (Elite/Class I and Class III) and naive observers rated 30 performances of a 30-sec pass from a compulsory balance beam routine (Class III girls). The same performances were rated for technical execution and aesthetic quality under point-light and normal viewing conditions. Within observer groups there were no differences in scores for technical execution or aesthetic quality. Correlation analyses indicated that all three groups of observers rated performances with similar trends across point-light and normal display conditions for technical execution (range 0.67–0.87). Significantly lower correlations were found for aesthetic quality within all three groups(range 0.46–0.56). Naive observers showed the highest correlations between technical execution and aesthetic quality in both point-light and normal display conditions. Results suggest that transformational information provides much of necessary information for the evaluation of technical execution and aesthetic quality although observer experience affects the pick-up of this information.  相似文献   

10.
Athletes rely on subjective assessment of complex movements from coaches and judges to improve their motor skills. In some sports, such as diving, snowboard half pipe, gymnastics, and figure skating, subjective scoring forms the basis for competition. It is currently unclear whether this scoring process can be mathematically modeled; doing so could provide insight into what motor skill is. Principal components analysis has been proposed as a motion analysis method for identifying fundamental units of coordination. We used PCA to analyze movement quality of dives taken from USA Diving’s 2009 World Team Selection Camp, first identifying eigenpostures associated with dives, and then using the eigenpostures and their temporal weighting coefficients, as well as elements commonly assumed to affect scoring – gross body path, splash area, and board tip motion – to identify eigendives. Within this eigendive space we predicted actual judges’ scores using linear regression. This technique rated dives with accuracy comparable to the human judges. The temporal weighting of the eigenpostures, body center path, splash area, and board tip motion affected the score, but not the eigenpostures themselves. These results illustrate that (1) subjective scoring in a competitive diving event can be mathematically modeled; (2) the elements commonly assumed to affect dive scoring actually do affect scoring (3) skill in elite diving is more associated with the gross body path and the effect of the movement on the board and water than the units of coordination that PCA extracts, which might reflect the high level of technique these divers had achieved. We also illustrate how eigendives can be used to produce dive animations that an observer can distort continuously from poor to excellent, which is a novel approach to performance visualization.  相似文献   

11.
The purpose of this study was to examine judges’ written reasons for sentencing in preventative detention hearings and the expert risk assessment reports presented, to determine the level of reliance placed on expert risk assessment reports and to examine the presence of partisan allegiance within the Canadian context. Results demonstrated that judges’ decisions were consistent with expert assessments in terms of risk, treatment amenability, and risk management. Experts’ ratings of treatment amenability and risk management were also significant predictors of the designation outcome, indicating that judges rely on this information in making their final decision. Finally, there was evidence of partisan allegiance, with prosecution-retained Psychopathy Checklist-Revised scores being significantly higher than defense-retained experts’ scores. The results have implications for the development of consistent guidelines for the communication of risk, treatment amenability, and management information. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

12.
Whilst benefits of an external focus are shown to govern several characteristics of skill execution, specificity theory indicates that sources of afferent information most useful to performance execution are typically prioritised during processing.ObjectivesWe investigated whether an internal focus facilitates performance when pertinent afferent information is proprioceptive in nature and congruent with attentional focus. We also considered whether the mechanisms behind attentional focus differences are attributable to planning processes or online motor control.DesignExperiments 1 and 2 adopted a randomised design, whilst experiment 3 used a repeated measures approach.MethodIn Experiment 1 we investigated movement variability as a measure of planning and error correction under external and internal focus conditions in an aiming task. Experiment 2 removed visual information to increase pertinence of proprioceptive feedback for movement execution and Experiment 3 adopted a leg-extension task, where proprioceptive salience was enhanced using an ankle weight. We hypothesised that this would increase congruency between internal focus instructions and movement production.ResultsExperiments 1 and 2 revealed reduced amplitude errors under an internal focus whilst Experiment 3 showed similar findings with the addition of lower EMG activity when adopting an internal focus. Movement variability findings were indicative of enhanced planning.ConclusionsWhen pertinence of proprioceptive information was amplified, benefits of an internal focus were more pronounced and performance was higher. Participants were better able to focus on movement characteristics to process proprioceptive feedback: something not afforded under an external focus. This raises doubts regarding the rigidity of the constrained action hypothesis.  相似文献   

13.
Summary The aim of the present study was to investigate the processes underlying aiming movements (motor programming and feedback control), and to explore their modification through learning. Two groups of 6- and 9-year-old children were asked to perform a directional aiming task without visual feedback (open-loop situation). After 15 trials (pretest) all subjects were submitted to a practice session which consisted of three series of trials with visual feedback (closed-loop situation). Half of the subjects had to perform the task at maximum speed (programmed movements), while the other half was required to perform slow movements (feedback-controlled movements). After the practice session all subjects were tested again in the openloop situation without time constraints (posttest). The results showed that during the practice session, accuracy was greater than in the two test conditions. It was greater in the case of slow movements than in the case of rapid ones. Moreover, in the case of rapid movements, it did not improve over the three practice series, while it did improve with slow movements. The difference between pre- and posttests showed that both groups improved their accuracy with practice in all conditions, the greatest improvement being obtained with rapid practice movements in 9-year-old children. It is suggested that different types of feedback (on-line and delayed feedback) contribute in varying degrees to the improvement of the aiming movements. However, the rapid movement condition, which requires a greater efficiency of programming, was found to be more effective for learning than the slow movement condition. The age-related differences found in learning suggest that feedback information can be fully integrated into motor programming only after 6 years of age.  相似文献   

14.
Are tool characteristics represented in imagined tool actions? In two experiments participants imagined and executed coloring rectangles with a thick and a thin pen. In Experiment 2, an additional execution condition without visual feedback of coloring allowed us to dissociate between the relevance of kinesthetic and visual feedback. Pen thickness influenced coloring durations in all conditions, indicating that characteristics of a simple tool are represented during imagery. Imagination was shorter than execution, indicating that imagination may be less detailed than execution. Execution without visual feedback was even shorter than imagination, indicating that vision is more important than kinesthesis for differences between imagination and execution, and that either imagining the movement, inhibiting movement execution or imagining the progress of the action is effortful during imagery. In conclusion, characteristics of simple tools are represented in imagined tool actions but the representation of tools’ effects may not always be adequate.  相似文献   

15.
The timing of visual information pick-up for visual anticipation was examined by comparing the capability of multiple skill groups, expert and near-expert karate athletes and novices, to block attacks using an in situ temporal occlusion paradigm. Participants stood facing a karate opponent and then attempted to block attacks (kicks and punches), whilst their vision of attacks was occluded: (a) prior to onset of opponent motion (O1), (b) after preparatory head movement (O2), and (c) after initiation of the attacking motion (O3). A no occlusion control condition provided complete vision of attacks (O4). Results revealed that expert anticipation was not significantly different to that of near-experts at O1, but was significantly different to the other group across O2–O4. Expert anticipation, however, was significantly above chance across all occlusion conditions, but near-experts performed above chance at O3 and O4, whilst novices were better than chance at O4. Unexpectedly, unique evidence was found that expert anticipation could be differentiated from near-expert anticipation in the earliest occlusion condition, where it was found that only experts were capable of using visual information from a static opponent to anticipate and block attacks above chance. The findings further understanding of expert visual anticipation to guide motor skills beyond existing expert–novice comparisons.  相似文献   

16.
In this paper, I deploy Gallagher et al.’s theory of Direct Social Perception (DSP) to help explain how we perceive others’ subjective time. This process of second-person temporal perception plays an important role in interpersonal interaction, yet is often glossed over in discussions of intersubjectivity. Using A.D. Craig (2009) ‘awareness’ model of subjective time to unify converging evidence that subjective time is embodied, affective, and situated, I argue that subjective time cannot be considered as a hidden or invisible aspect of a private mind, but is partially externally visible through our gestures, expressions, and other behaviours as they unfold within a particular context. My central thesis is that, in face to face interactions, we are able to directly perceive these visible components of other people’s subjective time. This is made possible by our “enculturated” (Menary, 2015) and enactive perceptual faculties. The process of social perception is not a passive, unidirectional affair where static information about one person’s subjective time is transmitted to the other, but rather inextricably linked with action (both at the personal and subpersonal level) and interaction effects produced by a dynamic coupling between participants. Such an enactive perspective reveals how others’ subjective time can be perceived in everyday interactions.  相似文献   

17.
Positive affect focused therapies could increase subjective happiness and life satisfaction for patients with eating disorders (EDs), illnesses known to significantly impact quality of life. This longitudinal pilot study aimed to develop and implement a five session ‘Positivity Group’ using positive psychology interventions (PPIs) in an adolescent ED inpatient service. Eight female inpatients aged 11–18 years attended the group and subjective happiness and life satisfaction were assessed before, after and at 6-month follow-up. Patients provided feedback on acceptability and feasibility was assessed via patient engagement, facilitator and team feedback and the data support the feasibility and acceptability of the group. A possible benefit was derived from the group, with 75% of patients reporting meaningful improvement in subjective happiness and 87.5% in life satisfaction. Involving the wider team and supporting homework were identified as considerations for future replication alongside the assessment of implementation, acceptability, feasibility and effectiveness in other clinical contexts.  相似文献   

18.
The Creative Solution Diagnosis Scale (CSDS) is a 30‐item scale based on a core of four criteria: Relevance & Effectiveness, Novelty, Elegance, and Genesis. The CSDS offers potential for the consensual assessment of functional product creativity. This article describes an empirical study in which non‐expert judges rated a series of mousetrap designs using the 30‐item CSDS. A confirmatory factor analysis revealed a simple structure that corresponded closely to the a priori theoretical model of functional creativity, resulting in a revised 24‐item CSDS. Non‐expert judges were able to use the scale with a high degree of reliability and internal consistency. The revised CSDS paves the way for further research into the use of non‐expert judges as a possible replacement for more costly, harder‐to‐obtain experts when measuring product creativity using the Consensual Assessment Technique (CAT).  相似文献   

19.
The Remember–Know paradigm is commonly used to examine experiential states during recognition. In this paradigm, whether a Know response is defined as a high-confidence state of certainty or a low-confidence state based on familiarity varies across researchers, and differences in definitions and instructions have been shown to influence participants’ responding. Using a novel approach, in three internet-based questionnaires participants were placed in the role of ‘memory expert’ and classified others’ justifications of recognition decisions. Results demonstrated that participants reliably differentiated between others’ memory experiences – both in terms of confidence and other inherent differences in the justifications. Furthermore, under certain conditions, manipulations of confidence were found to shift how items were assigned to subjective experience categories (Remember, Know, Familiar, and Guess). Findings are discussed in relation to the relationship between subjective experience and confidence, and the separation of Know and Familiar response categories within the Remember–Know paradigm.  相似文献   

20.
In two experiments, we examined the attentional mechanisms governing sensorimotor skill execution across levels of expertise. In Experiment 1, novice and expert golfers took a series of putts under dual-task conditions designed to distract attention from putting and under skill-focused conditions that prompted attention to step-by-stePperformance. Novices performed better under skill-focused than under dual-task conditions. Experts showed the opposite pattern. In Experiment 2, novice and expert golfers putted under instructions that emphasized either putting accuracy or speed—the latter intended to reduce the time available to monitor and explicitly adjust execution parameters. Novices putted better under accuracy instructions. Experts were more accurate under speed instructions. In agreement with theories of skill acquisition and automaticity, novice performance is enhanced by conditions that allow for on-line attentional monitoring (e.g., skill-focused or accuracy instructions) in comparison with conditions that prevent explicit attentional control of skill execution (e.g., dual-task or speed constraints). In contrast, the proceduralized skill of experts benefits from environments that limit, rather than encourage, attention to execution.  相似文献   

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