In this study we investigated redundancy control in joint action. Ten participantpairs (dyads) performed a virtual lifting task in which isometric forces needed to be generated with two or four hands. The participants were not allowed to communicate but received continuous visual feedback of their performance. When the task had to be performed with four hands, participants were confronted with a redundant situation and between-hand force synergies could, in principle, be formed. Performance timing, success rates, cross-correlations, and relative phase analyses of the force-time functions were scrutinized to analyze such task-dependent synergies. The results show that even though the dyads performed the task slower and less synchronized in the joint than in the solo conditions, the success rates in these conditions were identical. Moreover, correlation and relative phase analyses demonstrated that, as expected, the dyads formed between-participant synergies that were indicative of force sharing in redundant task conditions.
Jurjen Bosga and Ruud G. J. Meulenbroek
Jurjen Bosga, Ruud G. J. Meulenbroek and Raymond H. Cuijpers
In this study, we investigate how two persons (dyads) coordinate their movements when performing cyclical motion patterns on a rocking board. In keeping with the Leading Joint Hypothesis (Dounskaia, 2005), the movement dynamics of the collaborating participants were expected to display features of a prime mover with low movement variability. Fourteen subject pairs performed the task in nine amplitude-frequency combinations that were presented in the form of a to-be-tracked stimulus on a computer display. Participants were asked to track the stimulus by jointly rocking the Board sideways while receiving continuous visual feedback of its rotations. Displacements of 28 IREDS that were attached to the rocking board, both ankles, knees, hips, shoulders and heads of both actors, were sampled at 75 Hz by means of a 3D-motion tracking system. From these data, we derived body-segment angular excursions as well as the continuous relative phase and time-lagged cross-correlations between relevant joint excursions. The results show that, at the intrapersonal level, knee rotations initially led all other joints in time while the antiphase coordination between the knees displayed relative low variability. At the interpersonal level, dyads adopted a leader-follower strategy with respect to the coordination demands of the task. We take that knee rotations create a dynamic foundation at both intra- and interpersonal levels involving subordination of individual action to joint performance thereby allowing for low-dimensional control of joint action in a high-dimensional, repetitive motor task.
Cornelia Frank, Gian-Luca Linstromberg, Linda Hennig, Thomas Heinen and Thomas Schack
systematic and repeated use of this kind of imagery team action imagery training. From a cognitive psychology perspective, joint action has received tremendous research interest in the last two decades. Joint action represents “any form of social interaction whereby two or more individuals coordinate their
Dean Barker, Tristan Wallhead, Sheri Brock, Victoria Goodyear and Chantal Amade-Escot
Student group work is a central feature of many contemporary pedagogical approaches to teaching physical education. Despite this proliferation, our understanding of the teaching-learning dynamics inherent in group work remains limited and has tended to be under-theorized. The purpose of this paper was to examine different theoretical approaches to group work to identify similarities and differences and consequently provide insights and recommendations into ways of using group work as a pedagogical strategy. Four theoretical approaches to group work models were described in detail with brief empirical examples used to illustrate aspects to which each approach draws attention. The examination demonstrates conceptual overlap, elaboration and distinctions between the theoretical approaches related to: (i) content knowledge; (ii) engaging learners; (iii) the teacher’s role; and (iv) group composition. Meta-theoretical discussions of teaching strategies such as group work generate important discourse on the potential for the development of effective pedagogical practice.
Deborah Hebling Spinoso, Nise Ribeiro Marques, Dain Patrick LaRoche, Camilla Zamfollini Hallal, Aline Harumi Karuka, Fernanda Cristina Milanezi and Mauro Gonçalves
speed walking; (2) determine strength thresholds associated with 80% FD for each joint action such that targets can be set for exercise training and rehabilitation that may assist in the preservation of mobility with aging. The first hypothesis was that older women would have greater FD at habitual gait
This paper explores how young girls develop trust in their equine partners for the purposes of competitive equestrian sport. I argue that interspecies trust manifests through interactional trust and system trust. Interactional trust, as reflected in the horse-human relationship, is built through joint action and results in symbolic interaction. System trust is made possible through the equine community; it develops through communication in an effort to reduce complexity and uncertainty in society. To encourage and sustain youth participation in competitive equestrian sports both interactional trust and system trust are necessary.
Rachael D. Seidler, Jay L. Alberts and George E. Stelmach
The purpose of this study was to determine whether elderly adults exhibit deficits in the performance of multi-joint movements. Two groups of subjects (mean ages, 68.9 and 30.1 years, respectively) participated in this experiment. Subjects performed planar arm pointing movements to various targets. One target could be achieved via elbow extension only, while the remaining 3 required both elbow extension and horizontal shoulder flexion, thus requiring coordination at the 2 joints. In contrast to the young adults, the elderly adults produced movements that became less smooth and less accurate with increasing shoulder joint contribution. The results imply a selective coordination deficit for the elderly adults. In addition, the elderly adults coactivated opposing muscles more than the young adults for the single-joint movement. However, the elderly adults reduced coactivation at both joints for the 2-joint actions, while the young adults did not. These data suggest a relationship between high coactivation levels and good performance for elderly adults. It may be more difficult for the elderly to implement high coactivation levels for multi-joint movements because of the increased energy costs and complexity of planning required in comparison to the single joint actions. Thus, to achieve motor performance, elderly persons appear to use coactivation in a manner that is fundamentally different than young adults.
Breanna E. Studenka and Kodey Myers
’ intentions as often as TD children did. They did, however, improve joint action over time (see Gillam, Hartzheim, Studenka, Simonsmeier, & Gillam, 2015 ; Studenka et al., 2017 ). Joint action, in this study, refers to the coordinated interaction of two people completing the motor task of hammering a peg
Laura Misener, Landy Di Lu and Robert Carlisi
perspective. According to Emerson et al. ( 2012 ), three basic components of collaborative dynamics include principled engagement, shared motivation, and capacity for joint action. Principled engagement includes recruitment of many different stakeholders defined by their own unique set of “content
Mary Hellen Morcelli, Dain Patrick LaRoche, Luciano Fernandes Crozara, Nise Ribeiro Marques, Camilla Zamfolini Hallal, Mauro Gonçalves and Marcelo Tavella Navega
torque development thresholds predictive of functional gait speeds for each joint action. Until now, no study has simultaneously compared the strengths of the 3 primary lower limb joints and their relation with gait speed in older adults. Therefore, this study aims to test the ability of peak torque and