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1.
In the visual perception perspective of observational learning, the manipulation of relative and absolute motion information in visual demonstrations optimally directs learners’ search towards appropriate task solutions. We assessed the effect of emphasizing transformational information and removal of structural information using point-light kinematic displays in approximating the model’s relative motion patterns. Participants viewed computer-simulated point-light demonstrations or normal video demonstrations before and intermittently throughout 100 acquisition trials with knowledge of results on an underarm modified-dart aiming task. On the next day, all participants performed 20 retention trials without demonstrations. The kinematics of spatial and temporal coordination and control variables were examined relative to the model’s action, as well as performance scores. The results indicated that approximation of the model’s spatial and temporal coordination and control patterns was achieved after observation of either type of demonstrations. No differences were found in movement outcomes. In a second experiment, the effects of manipulating absolute motion information by slowmotion demonstrations were examined relative to real-time demonstrations. Real-time demonstrations led to a closer approximation to the model’s spatial and temporal coordination patterns and better outcome scores, contradicting predictions that slow-motion displays convey intact relative motion information. We speculate that the effect of visual demonstration speed on action perception and reproduction is a function of task constraints ‐ that is, novelty or familiarity of relative motion of demonstrated activities.  相似文献   

2.
In Experiment 1, adult and child participants were instructed to imitate a video model performing a bowling action with or without a ball. Participants imitated the action with greater accuracy without a ball and in general adults were more accurate than children. In Experiment 2, adults and children were shown a video or point-light display of the bowling action. There was no difference in movement form between the adult point-light and video groups. In contrast, children were poorer at reproducing the action when viewing point-light compared with video sequences (P < 0.05). The novel point-light display hindered the children's ability to provide conceptual mediation between the presented information and action requirements. In Experiment 3, a child point-light group was provided with perceptual-cognitive training. The perceptual-cognitive training group demonstrated better movement reproduction than a group who viewed the point-light displays with no training (P < 0.05), although there were no differences between participants who received training and those who viewed a video. Children are able to perceive and use relative motion information from a display after some general training, and the effectiveness of demonstrations needs to be judged relative to the task context.  相似文献   

3.
In this study, we examined the visual search strategies used during observation of video and point-light display models. We also assessed the relative effectiveness of video and point-light models in facilitating the learning of task outcomes and movement patterns. Twenty-one female novice soccer players were divided equally into video, point-light display and no-model (control) groups. Participants chipped a soccer ball onto a target area from which radial and variable error scores were taken. Kinematic data were also recorded using an opto-electrical system. Both a pre- and post-test were performed, interspersed with three periods of acquisition and observation of the model. A retention test was completed 2 days after the post-test. There was a significant main effect for test period for outcome accuracy and variability, but observation of a model did not facilitate outcome-based learning. Participants observing the models acquired a global movement pattern that was closer to that of the model than the controls, although they did not acquire the local relations in the movement pattern, evidenced by joint range of motion and angle-angle plots. There were no significant differences in learning between the pointlight display and video groups. The point-light display model group used a more selective visual search pattern than the video model group, while both groups became more selective with successive trials and observation periods. The results are discussed in the context of Newell's hierarchy of coordination and control and Scully and Newell's visual perception perspective.  相似文献   

4.
In this study, we examined the visual search strategies used during observation of video and point-light display models. We also assessed the relative effectiveness of video and point-light models in facilitating the learning of task outcomes and movement patterns. Twenty-one female novice soccer players were divided equally into video, point-light display and no-model (control) groups. Participants chipped a soccer ball onto a target area from which radial and variable error scores were taken. Kinematic data were also recorded using an opto-electrical system. Both a pre- and post-test were performed, interspersed with three periods of acquisition and observation of the model. A retention test was completed 2 days after the post-test. There was a significant main effect for test period for outcome accuracy and variability, but observation of a model did not facilitate outcome-based learning. Participants observing the models acquired a global movement pattern that was closer to that of the model than the controls, although they did not acquire the local relations in the movement pattern, evidenced by joint range of motion and angle-angle plots. There were no significant differences in learning between the point-light display and video groups. The point-light display model group used a more selective visual search pattern than the video model group, while both groups became more selective with successive trials and observation periods. The results are discussed in the context of Newell's hierarchy of coordination and control and Scully and Newell's visual perception perspective.  相似文献   

5.
In this article, we examine the question of what information is processed during observational learning by evaluating a variety of methods, theories, and empirical data. Initially, we review work involving neuroimaging techniques and infant imitation. We then evaluate data from behavioural experiments involving adults, wherein a variety of attempts have been made to isolate the critical or minimal information constraining the acquisition of coordination. This body of research has included comparisons between video and point-light displays, manipulations to the amount and type of information presented in the display, the collection of point-of-gaze data, and manipulations to the task context in terms of outcome goals. We conclude that observational learning is governed by specific features of the model's action (i.e. motions of the end effector) and the task (i.e. outcome constraints) and, in contrast with traditional theoretical modelling, more global aspects of a model (i.e. the relative motions within and between joints) do not appear to be the primary method for constraining action execution.  相似文献   

6.
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7.
Although research has examined the influence of various sources of task information for skill acquisition during observational learning, the results have been ambiguous. The purpose of this study was to examine sources of information in relation to the type of task. One hundred and twenty participants were randomly assigned to one of two sets of six treatment strategies: (1) all model demonstrations; (2) model demonstrations with physical practice with knowledge of performance; (3) model demonstrations with physical practice without knowledge of performance; (4) physical practice without knowledge of performance; (5) physical practice with knowledge of performance; or (6) verbal instructions only. One set learned a simple version of the task while the other set learned a more complex version. Cognitive representation and performance accuracy (spatial and temporal) were assessed. Results indicate that task type does influence the source of information to facilitate skill acquisition. The simple task benefited from model demonstrations, physical practice with knowledge of performance, or a combination of model demonstrations and practice both with and without knowledge of performance, while the complex version benefited more from a combination of model demonstrations and knowledge of performance practice. The results of this study provide an insight into the ambiguity that exists within the observational learning and motor learning literature regarding the effectiveness of information sources for motor skill acquisition.  相似文献   

8.
The need to identify information sources which facilitate a functional coupling of perception and action in representative practice contexts is an important challenge for sport scientists and coaches. The current study investigated the role of visual information in regulating athlete gait behaviours during a locomotor pointing task in cricket. Integration of experiential knowledge of elite coaches and theoretical understanding from previous empirical research led us to investigate whether the presence of an umpire would act as a vertical informational constraint that could constrain the emergent coordination tendencies of cricket bowlers’ run-up patterns. To test this idea, umpire presence was manipulated during run-ups of 10 elite medium-fast bowlers. As hypothesised, removal of the umpire from the performance environment did not result in an inability to regulate gait to intercept a target, however, the absence of this informational constraint resulted in the emergence of different movement patterns in participant run-ups. Significantly lower standard deviation values of heel-to-crease distances were observed in the umpire condition at multiple steps, compared to performance in the no-umpire condition. Manipulation of this informational constraint altered gait regulation of participants, offering a mechanism to understand how perception–action couplings can be varied during performance in locomotor pointing tasks in sport.  相似文献   

9.
Abstract

Although research has examined the influence of various sources of task information for skill acquisition during observational learning, the results have been ambiguous. The purpose of this study was to examine sources of information in relation to the type of task. One hundred and twenty participants were randomly assigned to one of two sets of six treatment strategies: (1) all model demonstrations; (2) model demonstrations with physical practice with knowledge of performance; (3) model demonstrations with physical practice without knowledge of performance; (4) physical practice without knowledge of performance; (5) physical practice with knowledge of performance; or (6) verbal instructions only. One set learned a simple version of the task while the other set learned a more complex version. Cognitive representation and performance accuracy (spatial and temporal) were assessed. Results indicate that task type does influence the source of information to facilitate skill acquisition. The simple task benefited from model demonstrations, physical practice with knowledge of performance, or a combination of model demonstrations and practice both with and without knowledge of performance, while the complex version benefited more from a combination of model demonstrations and knowledge of performance practice. The results of this study provide an insight into the ambiguity that exists within the observational learning and motor learning literature regarding the effectiveness of information sources for motor skill acquisition.  相似文献   

10.
The purpose of this study was to determine the sources of visual information used by highly skilled tennis players in anticipating their opponent's shots. In Experiment 1, motion analysis of the strokes showed that the relative motion between the racquet and forearm was different between the ground strokes and lobs, but there were no reliable kinematic differences when shot direction was varied. In Experiment 2, 12 skilled tennis players observed the opponent hitting strokes in a normal video or in a point-light display with different segments occluded. Players' anticipation accuracy was not degraded by the use of the point-light display. Occluding the racquet and forearm significantly reduced the participant's ability to determine the type of stroke produced.  相似文献   

11.
We compared the visuomotor coordination of tennis players with different levels of expertise (Super-Experts, Experts and Non-Experts) in a visuomotor tracking (VMT) task. Participants were asked to track a moving target which could rebound on the sides of a 2D screen. Results indicated that the VMT task allowed the discrimination of expertise. Multiple regression analysis revealed that performance could be explained by the temporal adaptation of participants to rebounds and the number of movement adaptations. Compared to Non-Experts, the Experts had a shorter perturbation time with higher adaptation and regulation. This corresponds to a better perception–action coupling and the predominant use of a prospective control process. Results also indicate that perception–action coupling capacities are transferable to virtual tasks, and allow us to reveal processes of visuomotor coordination that differentiate experts and novices.  相似文献   

12.
We examined whether altering the amount of and moment when visual information is presented affected observational learning for participants practicing a bowling skill. On Day 1, four groups practiced a cricket bowling action. Three groups viewed a full-body point-light model, the model's bowling arm, or between-limb coordination of the model's left and right wrists only. Following retention tests on Day 2, all participants practiced after viewing a full-body display. Retention was again tested on Day 3. Bowling accuracy improved in all four practice groups. Kinematics of the bowling arm became more like the model for the full-body and intralimb groups only. All groups improved on measures of interlimb coordination. Visual search data indicated that participants mainly focused their gaze on the model's bowling arm. These data lead to the suggestion that viewing “end-effector” information (i.e., information pertaining to the bowling arm) is an important perceptual constraint early in observational learning. Implicit manipulations designed to increase attention to other sources of information did not facilitate the learning process.  相似文献   

13.
The aims of this study were to examine the effect of different environmental constraints on kinematic multi-segment coordination patterns during the service and its coordination with service time variability. Ten expert tennis players (Age: 34.1 ± 5.3) volunteered to take part in this study. Participants served 30 times in 3 different conditions: control, target and opposition. The order of conditions was counterbalanced between participants. A wireless 3D motion capture system (STT Co, Spain) was used to measure 7 joint motions, with a 17 degrees of freedom biomechanical model created to capture the entire service action. Results of the principal component analysis showed that 4 synergies were created; however, their roles were changed relative to the perception of the environment. The results of repeated-measures analysis of variance did not show any significant difference on total variance and individual principal components between conditions; however, one synergy pattern significantly predicted the service time variability in both control and opposition conditions. In conclusion, the findings demonstrated that expert performers reduce the joint dimensionality by creating functional synergies in different phases of service and adapt the service action according to the perception of the environment.  相似文献   

14.
The perception of a human actor performing movements may involve processes related to action execution. This resonance of the motor system may support observational learning and imitation, and could also explain the fact that observers'/actors' movements are disturbed by the observation of a human model making different movements (Kilner et al., 2003). In this study, we tried to specify what information available in the model's behaviour triggers this influence on an observer's behaviour. In two experiments, we had participants make horizontal or vertical arm movements while observing similar movements. In the first experiment, the observers' pattern of behaviour was affected by the observation of a human model making incongruent movements. In the second experiment, similar results were obtained with participants observing a moving dot depicting either biological or non-biological motion. Movement execution was affected differentially by biological and non-biological motion observation. These results show that an observer's behaviour is sensitive to information available in biological motion.  相似文献   

15.
The study investigated the coordination and variability of posture and pistol motion for skilled pistol shooters and novices in a pistol-aiming task. The participants stood on a force platform and held a pistol with the preferred arm to aim for accuracy to a target on 30 s trials. The results revealed that the amount of the centre of pressure (COP) and pistol motion was lower for the expert than novice group. The time–varying structure of COP as indexed by multiscale entropy (MSE) and detrended fluctuation analysis (DFA) was also lower for the expert than the novice group. The relative phase between the COP in the anterior–posterior (AP) and pistol in the AP and between the COP in the medial–lateral (ML) and pistol in AP was close to inphase for the both groups. However, for the novice group the coordination patterns of posture and pistol motion were more variable with the pistol motion leading the posture motion while it was lagging in the skilled group. The findings show different qualitative and quantitative dynamics in pistol-aiming as a function of skill level with postural control foundational to supporting the reduced dispersion and complexity of the skilled arm-pistol motion.  相似文献   

16.
To visually perceive opportunities for action, athletes rely on the movements of their eyes, head and body to explore their surrounding environment. To date, the specific types of technology and their efficacy for assessing the exploration behaviours of association footballers have not been systematically reviewed. This review aimed to synthesise the visual perception and exploration behaviours of footballers according to the task constraints, action requirements of the experimental task, and level of expertise of the athlete, in the context of the technology used to quantify the visual perception and exploration behaviours of footballers. A systematic search for papers that included keywords related to football, technology, and visual perception was conducted. All 38 included articles utilised eye-movement registration technology to quantify visual perception and exploration behaviour. The experimental domain appears to influence the visual perception behaviour of footballers, however no studies investigated exploration behaviours of footballers in open-play situations. Studies rarely utilised representative stimulus presentation or action requirements. To fully understand the visual perception requirements of athletes, it is recommended that future research seek to validate alternate technologies that are capable of investigating the eye, head and body movements associated with the exploration behaviours of footballers during representative open-play situations.  相似文献   

17.
We assessed the effects on basketball free throw performance of two types of verbal directions with an external attentional focus. Novices (n = 16) were pre-tested on free throw performance and assigned to two groups of similar ability (n = 8 in each). Both groups received verbal instructions with an external focus on either movement dynamics (movement form) or movement effects (e.g. ball trajectory relative to basket). The participants also observed a skilled model performing the task on either a small or large screen monitor, to ascertain the effects of visual presentation mode on task performance. After observation of six videotaped trials, all participants were given a post-test. Visual search patterns were monitored during observation and cross-referenced with performance on the pre- and post-test. Group effects were noted for verbal instructions and image size on visual search strategies and free throw performance. The 'movement effects' group saw a significant improvement in outcome scores between the pre-test and post-test. These results supported evidence that this group spent more viewing time on information outside the body than the 'movement dynamics' group. Image size affected both groups equally with more fixations of shorter duration when viewing the small screen. The results support the benefits of instructions when observing a model with an external focus on movement effects, not dynamics.  相似文献   

18.
Abstract

This study was designed to investigate selected spatial and temporal characteristics of movement. Forty-one subjects were administered the rhythm test of the Drake Musical Aptitude Tests. From the resulting distribution of scores, 10 subjects with a high level and 10 subjects with a low level of rhythmic ability were filmed while performing a simple rhythmic movement task. The task, done to a fixed metronomic rate of 66 beats/minute, consisted of a forward lunge in which the arm was swung forward and upward until the hand was directly in line with a target. The subject had to stop the motion of her arm in such a position that her hand was in line with the target on every other beat of the metronome, and recover to a starting position on the alternate beats. The subjects responded to eight beats while standing in place and to eight while responding in the described manner. The movement task was recorded on film; deviations in the time and space at the moment of the stimulus were estimated in a frame-by-frame analysis of the film. An analysis of variance of time and space scores was made using 9 subjects in the low group and 10 subjects in the high group. It was concluded that the true means of the absolute deviations in time and space of high and low performers on the Drake Rhythm Test were the same.  相似文献   

19.
Objectives: Slow-motion replays of foul play situations are now used in the education and training of sports officials. We investigated the impact of video speed on the decision-making process of association football referees and how this interacted with expertise. Methods: Three different groups of referees, varying in level of expertise, assessed video clips from an in-game perspective. Video clips represented corner kick and open play situations in which a foul occurred or not. For these foul/no foul situations, the referees had to make a technical (no foul; indirect free kick; direct free kick; or penalty kick) and a disciplinary decision (no card; yellow card; or red card), under both slow-motion and real-time viewing conditions. Accuracy scores were determined by comparing participant’s responses with the decisions of an expert panel. Results: Significant differences were observed across groups for foul/no foul situations, suggesting that the experts were able to process the available information more effectively than their less expert colleagues. The accuracy scores for the technical decision were higher in slow motion (67%) compared to a real-time viewing condition (56%), particularly for corner kick situations. No differences were found between real time and slow motion for the disciplinary decision. Conclusions: Slow-motion footage results in higher accuracy scores for complex technical decisions. These findings have implications for the use of slow-motion replays in the decision-making process of referees.  相似文献   

20.
We assessed the effects on basketball free throw performance of two types of verbal directions with an external attentional focus. Novices ( n = 16) were pre-tested on free throw performance and assigned to two groups of similar ability ( n = 8 in each). Both groups received verbal instructions with an external focus on either movement dynamics (movement form) or movement effects (e.g. ball trajectory relative to basket). The participants also observed a skilled model performing the task on either a small or large screen monitor, to ascertain the effects of visual presentation mode on task performance. After observation of six videotaped trials, all participants were given a post-test. Visual search patterns were monitored during observation and cross-referenced with performance on the pre- and post-test. Group effects were noted for verbal instructions and image size on visual search strategies and free throw performance. The 'movement effects' group saw a significant improvement in outcome scores between the pre-test and post-test. These results supported evidence that this group spent more viewing time on information outside the body than the 'movement dynamics' group. Image size affected both groups equally with more fixations of shorter duration when viewing the small screen. The results support the benefits of instructions when observing a model with an external focus on movement effects, not dynamics.  相似文献   

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