Movement coordination and control in children with and without Developmental Coordination Disorder in ball catching

Abstract

A rigorous investigation of functional collectives of musculo-skeletal articulators is lacking in DCD literature, in spite of powerful empirical arguments suggesting that they represent a critical unit of control (e.g., coordinative structure theory). Thus, the purpose of this dissertation was to examine how children with and without DCD coordinate and control their actions in a multi-degrees of freedom task, such as ball catching. The first study focused on the development of a protocol and qualitative measures capable of examining ball catching performance in children of varying skill levels. The second study involved a replication of the previously devised protocol with a larger group of individuals with and without DCD. The third phase involved a more in-depth analysis of spatial and temporal aspects of movement coordination and control using kinematics. Typically developing boys effectively coordinated and controlled their actions regardless of the task constraints. This confirms that by 10-11 years of age ball catching, and the underlying perceptual-motor mechanisms, are well developed. The analysis of the emerging tendencies showed that they coupled and decoupled the existing spatio-temporal coordinative relations depending on the task constraints, and biomechanical properties of the relevant elements involved. This supports the notion that optimal movement coordination reflects the ability to re-organize the relevant coordinative structures, given the existing constraints.