Postural and cardiac responses to suprapostural tasks among children with and without developmental coordination disorder.

Abstract

Developmental coordination disorder (DCD) is a diagnosis for children who present movement difficulties but are of normal intelligence without neurological deficits. Previous studies have preliminarily exploited postural and suprapostural task paradigm to research differences of motor characteristics between DCD and typically developmental children (TDC). However, to date no research has sought to investigate the postural and cardiac responses when performing perceptual-demanding and cognitive-demanding suprapostural tasks across task difficulties.The aim of the present investigation were to compare the effect of varying visual and memory demands of suprapostural tasks on postural motion and control of heart in children with DCD and TDC. Two groups of children (DCD and TDC) , aged between 9 and 10 years were recruited. They were instructed to execute a suprapostural visual and memory task with two difficulty levels, low difficulty (LD) and high difficulty (HD), separately while postural motion and cardiac activity were recording. Postural sway variability and cardiac parameters (HR, HF, LF/HF, sample entropy) were employed to determine motor and cardiac responses in corresponding to visual and memory tasks between DCD and TDC. Our findings demonstrated that (1) biomechanical and cardiac responses were less different between the two groups during suprapostural memory tasking, reflective of a comparable effect of suprapostural memory task on both groups, and (2) biomechanical and cardiac responses were significant different between DCD and TDC while engaging in suprapostural visual task, suggesting that TDC are capable of modulating postural motion to facilitate the goal of a visual demanding task but children with DCD are incapable.