75 research outputs found

    Education and transfer of water competencies: An ecological dynamics approach

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    © The Author(s) 2020. To cope in various aquatic environments (i.e. swimming pools, lakes, rivers, oceans), learners require a wide repertoire of self-regulatory behaviours such as awareness of obstacles and water properties, floating and moving from point to point with different strokes, decision making, emotional control and breathing efficiently. By experiencing different learning situations in stable indoor pool environments, it is assumed that children strengthen aquatic competencies that should be transferable to functioning in open water environments, where prevalence of drowning is high. However, this fundamental assumption may be misleading. Here, we propose the application of a clear, related methodology and theoretical framework that could be useful to help physical education curriculum specialists (re)shape and (re)design appropriate aquatic learning situations to facilitate better transfer of learning. We discuss the need for more representativeness in a learning environment, proposing how the many different task and environmental constraints on aquatic actions may bound the emergence of functional, self-regulatory behaviours in learners. Ideas in ecological dynamics suggest that physical educators should design learning environments that offer a rich landscape of opportunities for action for learners. As illustration, three practice interventions are described for developing functional and transferrable skills in indoor aquatic environments. It is important that aquatic educators focus not just upon ‘learning to swim’, but particularly on relevant transferable skills and self-regulatory behaviours deemed necessary for functioning in dynamic, outdoor aquatic environments

    Aging affects attunement in perceiving length by dynamic touch

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    Earlier studies have revealed age-dependent differences in perception by dynamic touch. In the present study, we examined whether the capacity to learn deteriorates with aging. Adopting an ecological approach to learning, the authors examined the process of attunement—that is, the changes in what informational variable is exploited. Young and elderly adults were trained to perceive the lengths of unseen, handheld rods. It was found that the capacity to attune declines with aging: Contrary to the young adults, the elderly proved unsuccessful in learning to detect the specifying informational variables. The fact that aging affects the capacity to attune sets a new line of research in the study of perception and perceptual-motor skills of elderly. The authors discuss the implications of their findings for the ongoing discussions on the ecological approach to learning

    Education and transfer of water competencies: An ecological dynamics approach

    Get PDF
    © The Author(s) 2020. To cope in various aquatic environments (i.e. swimming pools, lakes, rivers, oceans), learners require a wide repertoire of self-regulatory behaviours such as awareness of obstacles and water properties, floating and moving from point to point with different strokes, decision making, emotional control and breathing efficiently. By experiencing different learning situations in stable indoor pool environments, it is assumed that children strengthen aquatic competencies that should be transferable to functioning in open water environments, where prevalence of drowning is high. However, this fundamental assumption may be misleading. Here, we propose the application of a clear, related methodology and theoretical framework that could be useful to help physical education curriculum specialists (re)shape and (re)design appropriate aquatic learning situations to facilitate better transfer of learning. We discuss the need for more representativeness in a learning environment, proposing how the many different task and environmental constraints on aquatic actions may bound the emergence of functional, self-regulatory behaviours in learners. Ideas in ecological dynamics suggest that physical educators should design learning environments that offer a rich landscape of opportunities for action for learners. As illustration, three practice interventions are described for developing functional and transferrable skills in indoor aquatic environments. It is important that aquatic educators focus not just upon ‘learning to swim’, but particularly on relevant transferable skills and self-regulatory behaviours deemed necessary for functioning in dynamic, outdoor aquatic environments

    The effectiveness of constraint-led training on skill development in interceptive sports: a systematic review (Clark, McEwan and Christie) – a commentary

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    Clark, McEwan and Christie's systematic review1 offers a timely examination of current literature assessing effects of a constraints-led approach (CLA) to training on ‘technical and cognitive skill in sport’, in comparison to traditional training methods. They concluded that, currently, there is strong evidence to advocate for the effects of training interventions that espouse benefits of constraints-led training on acquiring skill in interceptive actions. Clark, McEwan and Christie reported that 18 studies satisfied their proposed inclusion criteria and, of these studies, 77% provided evidence of the effectiveness of the CLA. Consequently, Clark, McEwan and Christie argued that a ‘the implementation of the constraints-led approach within interceptive sport can be advocated’ (p. 17). This is a revealing insight, which supports their claims that this finding ‘provides the opportunity for researchers to collect more compelling evidence to answer the question: “Does constraint-led training assist with the development of technical skills within interceptive sport?”’. While we endorse their call for more empirical evidence on the effectiveness of a CLA to practice and training design, we qualify it by highlighting some limitations of Clark, McEwan and Christie's systematic review

    Attractor dynamics approach to joint transportation by autonomous robots: theory, implementation and validation on the factory floor

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    This paper shows how non-linear attractor dynamics can be used to control teams of two autonomous mobile robots that coordinate their motion in order to transport large payloads in unknown environments, which might change over time and may include narrow passages, corners and sharp U-turns. Each robot generates its collision-free motion online as the sensed information changes. The control architecture for each robot is formalized as a non-linear dynamical system, where by design attractor states, i.e. asymptotically stable states, dominate and evolve over time. Implementation details are provided, and it is further shown that odometry or calibration errors are of no significance. Results demonstrate flexible and stable behavior in different circumstances: when the payload is of different sizes; when the layout of the environment changes from one run to another; when the environment is dynamice.g. following moving targets and avoiding moving obstacles; and when abrupt disturbances challenge team behavior during the execution of the joint transportation task.- This work was supported by FCT-Fundacao para a Ciencia e Tecnologia within the scope of the Project PEst-UID/CEC/00319/2013 and by the Ph.D. Grants SFRH/BD/38885/2007 and SFRH/BPD/71874/2010, as well as funding from FP6-IST2 EU-IP Project JAST (Proj. Nr. 003747). We would like to thank the anonymous reviewers, whose comments have contributed to improve the paper

    Monkey Steering Responses Reveal Rapid Visual-Motor Feedback

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    The neural mechanisms underlying primate locomotion are largely unknown. While behavioral and theoretical work has provided a number of ideas of how navigation is controlled, progress will require direct physiolgical tests of the underlying mechanisms. In turn, this will require development of appropriate animal models. We trained three monkeys to track a moving visual target in a simple virtual environment, using a joystick to control their direction. The monkeys learned to quickly and accurately turn to the target, and their steering behavior was quite stereotyped and reliable. Monkeys typically responded to abrupt steps of target direction with a biphasic steering movement, exhibiting modest but transient overshoot. Response latencies averaged approximately 300 ms, and monkeys were typically back on target after about 1 s. We also exploited the variability of responses about the mean to explore the time-course of correlation between target direction and steering response. This analysis revealed a broad peak of correlation spanning approximately 400 ms in the recent past, during which steering errors provoke a compensatory response. This suggests a continuous, visual-motor loop controls steering behavior, even during the epoch surrounding transient inputs. Many results from the human literature also suggest that steering is controlled by such a closed loop. The similarity of our results to those in humans suggests the monkey is a very good animal model for human visually guided steering

    Vestibular Facilitation of Optic Flow Parsing

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    Simultaneous object motion and self-motion give rise to complex patterns of retinal image motion. In order to estimate object motion accurately, the brain must parse this complex retinal motion into self-motion and object motion components. Although this computational problem can be solved, in principle, through purely visual mechanisms, extra-retinal information that arises from the vestibular system during self-motion may also play an important role. Here we investigate whether combining vestibular and visual self-motion information improves the precision of object motion estimates. Subjects were asked to discriminate the direction of object motion in the presence of simultaneous self-motion, depicted either by visual cues alone (i.e. optic flow) or by combined visual/vestibular stimuli. We report a small but significant improvement in object motion discrimination thresholds with the addition of vestibular cues. This improvement was greatest for eccentric heading directions and negligible for forward movement, a finding that could reflect increased relative reliability of vestibular versus visual cues for eccentric heading directions. Overall, these results are consistent with the hypothesis that vestibular inputs can help parse retinal image motion into self-motion and object motion components

    Neurobiological degeneracy and affordance perception support functional intra-individual variability of inter-limb coordination during ice climbing

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    This study investigated the functional intra-individual movement variability of ice climbers differing in skill level to understand how icefall properties were used by participants as affordances to adapt inter-limb coordination patterns during performance. Seven expert climbers and seven beginners were observed as they climbed a 30 m icefall. Movement and positioning of the left and right hand ice tools, crampons and the climber's pelvis over the first 20 m of the climb were recorded and digitized using video footage from a camera (25 Hz) located perpendicular to the plane of the icefall. Inter-limb coordination, frequency and types of action and vertical axis pelvis displacement exhibited by each climber were analysed for the first five minutes of ascent. Participant perception of climbing affordances was assessed through: (i) calculating the ratio between exploratory movements and performed actions, and (ii), identifying, by self-confrontation interviews, the perceptual variables of environmental properties, which were significant to climbers for their actions. Data revealed that experts used a wider range of upper and lower limb coordination patterns, resulting in the emergence of different types of action and fewer exploratory movements, suggesting that effective holes in the icefall provided affordances to regulate performance. In contrast, beginners displayed lower levels of functional intra-individual variability of motor organization, due to repetitive swinging of ice tools and kicking of crampons to achieve and maintain a deep anchorage, suggesting lack of perceptual attunement and calibration to environmental properties to support climbing performanc

    Influence of Motor Planning on Distance Perception within the Peripersonal Space

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    We examined whether movement costs as defined by movement magnitude have an impact on distance perception in near space. In Experiment 1, participants were given a numerical cue regarding the amplitude of a hand movement to be carried out. Before the movement execution, the length of a visual distance had to be judged. These visual distances were judged to be larger, the larger the amplitude of the concurrently prepared hand movement was. In Experiment 2, in which numerical cues were merely memorized without concurrent movement planning, this general increase of distance with cue size was not observed. The results of these experiments indicate that visual perception of near space is specifically affected by the costs of planned hand movements
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