Developmental coordination disorder (DCD) occurs in a small number of children who present with impaired body/eye coordination. No study of ophthalmic function in DCD exists despite vision’s primary role in perception. Ocular performance was therefore assessed with a battery of tests. Five hundred children aged between 5 and 7 years were involved in the study. Diagnosis of DCD was confirmed for 29 children by the Movement Assessment Battery for Children (ABC); 29 control children were randomly selected. Comprehensive examination with a battery of ophthalmic tests did not reveal any significant difference in visual status between the two groups. Strabismus was found in 5 children from both groups. All 5 children with strabismus from the DCD group showed a similar movement profile with the Motor Competence Checklist. While a causal relationship cannot be discounted, the presence of strabismus appears more likely to be a “hard” neurological sign of central damage common to this group. The evidence seems to indicate that a simple ophthalmic difficulty does not explain problems with movement control.
Mark A. Mon-Williams, Eve Pascal and John P. Wann
Eli Carmeli, Tamar Bar-Yossef, Claudette Ariav, Rosy Paz, Hanna Sabbag and Ran Levy
Adults with intellectual disabilities (ID) show a greater tendency toward deconditioning and having a sedentary lifestyle than their peers without disabilities. The aim of this study was to characterize sensorimotor deficits through coordination tests and during static and dynamic balance. Eight tasks that involved the integration of hand movements with visual information were used here, as well as the Posture Scale Analyzer system to examine postural stability. During static and dynamic standing tests with the eyes closed, the postural stability of people with ID was accompanied by a small sway rate. In the ID group, the frontal plane movements were significantly larger (p > .05) than the sagittal plane movements. The participants with ID showed a significantly lower score than the control group in all the sensorimotor tests. Our observations on balance and coordination capabilities might have significance for understanding the mechanisms underlying movement dysfunction in adults with ID and offer some new approaches for their possible prevention.
Richard E.A. van Emmerik, Stephanie L. Jones, Michael A. Busa and Jennifer L. Baird
Postural instability, falls, and fear of falling that accompany frailty with aging and disease form major impediments to physical activity. In this article we present a theoretical framework that may help researchers and practitioners in the development and delivery of intervention programs aimed at reducing falls and improving postural stability and locomotion in older individuals and in those with disability due to disease. Based on a review of the dynamical and complex systems perspectives of movement coordination and control, we show that 1) central to developing a movement-based intervention program aimed at fall reduction and prevention is the notion that variability can play a functional role and facilitate movement adaptability, 2) intervention programs aimed at fall reduction should focus more on coordination and stability boundary measures instead of traditional gait and posture outcome variables, and 3) noise-based intervention techniques using stochastic resonance may offer external aids to improve dynamic balance control.
Allen W. Burton
Adapted physical education specialists must design and carry out programs for students with movement coordination problems, but intervention strategies for such students are rarely included in adapted physical education textbooks. In response to the lack of information available to practitioners, the purpose of this paper is to provide a conceptual framework for better understanding movement coordination, to briefly review some of the methods used by both researchers and practitioners to assess coordination, and to present some possible strategies for addressing movement coordination deficits. Two types of coordination solutions are discussed—neuromotor and mechanical—and specific activity progressions are given for jumping jacks and overhand throwing.
Sheila E. Henderson and Leslie Henderson
We consider three issues concerning unexpected difficulty in the acquisition of motor skills: terminology, diagnosis, and intervention. Our preference for the label Developmental Coordination Disorder (DCD) receives justification. Problems in diagnosis are discussed, especially in relation to the aetiology-dominated medical model. The high degree of overlap between DCD and other childhood disorders appears to militate against its acceptance as a distinct syndrome. In this context, we emphasize the need to determine whether incoordination takes different forms when it occurs alone is combined with general developmental delay or with other specific disorders in children of normal intelligence. Studies of intervention have mostly shown positive effects but do not, as yet, allow adjudication between different sorts of content. We suggest that the study of DCD and its remediation would benefit greatly from the employment of the simple but rich paradigms developed for the experimental analysis of fully formed adult movement skills.
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.
Robert Rein, Chris Button, Keith Davids and Jeffery Summers
The present paper proposes a technical analysis method for extracting information about movement patterning in studies of motor control, based on a cluster analysis of movement kinematics. In a tutorial fashion, data from three different experiments are presented to exemplify and validate the technical method. When applied to three different basketball-shooting techniques, the method clearly distinguished between the different patterns. When applied to a cyclical wrist supination-pronation task, the cluster analysis provided the same results as an analysis using the conventional discrete relative phase measure. Finally, when analyzing throwing performance constrained by distance to target, the method grouped movement patterns together according to throwing distance. In conclusion, the proposed technical method provides a valuable tool to improve understanding of coordination and control in different movement models, including multiarticular actions.
Betty Rose, Dawne Larkin and Bonnie G. Berger
Perceived competence and global self-worth of children who were poorly coordinated (n = 68) and children who were well-coordinated (n = 62) were examined. Measures of perceived athletic and scholastic competence, social acceptance, physical appearance, behavioral conduct, and global self-worth were obtained using Harter’s (1985) Self-Perception Profile for Children (SPPC). Girls and boys, ages 8 to 12, were categorized as poorly coordinated or well-coordinated using their scores on the McCarron (1982) Neuromuscular Development battery. Univariate analyses, using a 2 × 2 design (Coordination × Gender), showed a main effect of coordination in all domains, with the poorly coordinated group having the lower mean scores. In the scholastic, behavioral, and global sphere, coordination by gender interactions were influenced by the high perceptions of the well-coordinated girls. The interactions demonstrated for scholastic and global domains also were influenced by the low perceptions of the girls with poor coordination. Self-perceptions were modified by gender and coordination.
Zheng Wang, Peter C. M. Molenaar and Karl M. Newell
The experiment was set up to investigate the inter- and intrafoot coordination dynamics of postural control on balance boards. A frequency domain principal component analysis (PCA) was applied on 4 center of pressure (COP) time series collected from two force platforms to reveal their contributions to postural stability. The orientation of support played a more significant role than its width in channeling the foot coordination dynamics. When the support was oriented along the AP-challenging direction, the 4 COPs revealed a parallel contribution to the 1st principal component (PC1) indicating an interdependence of the foot coordination in both directions. When the support was positioned along the ML-challenging direction, the COPs in the AP direction showed larger weightings to PC1 implying an interfoot coordination. These findings provide evidence that COP coordination operates in adaptive ways to sustain postural stability in light of changing support constraints to standing.
Richard E.A. Van Emmerik, Michael T. Rosenstein, William J. McDermott and Joseph Hamill
Nonlinear dynamics and dynamical systems approaches and methodologies are increasingly being implemented in biomechanics and human movement research. Based on the early insights of Nicolai Bernstein (1967), a significantly different outlook on the movement control “problem” over the last few decades has emerged. From a focus on relatively simple movements has arisen a research focus with the primary goal to study movement in context, allowing the complexity of patterns to emerge. The approach taken is that the control of multiple degrees-of-freedom systems is not necessarily more difficult or complex than that of systems only comprising a few degrees of freedom. Complex patterns and dynamics might not require complex control structures. In this paper we present a tutorial overview of the mathematical underpinnings of nonlinear dynamics and some of its basic analysis tools. This should provide the reader with a basic level of understanding about the mathematical principles and concepts underlying pattern stability and change. This will be followed by an overview of dynamical systems approaches in the study of human movement. Finally, we discuss recent progress in the application of nonlinear dynamical techniques to the study of human locomotion, with particular focus on relative phase techniques for the assessment of coordination.