Hand preference in children with developmental coordination disorders: cause and effect?

Inter- and intra-modal matching by eight-year-old children diagnosed as having hand-eye coordination problems (HECP) and categorized as left-handed, together with a left-handed control group of children without such problems, were tested using a manual sensory matching task. The task required the children to locate target pins, visually (seen target), proprioceptively (felt target) or in combination (felt and seen target), while matching to the located target was always carried out without vision. Performance was superior when the target was located visually or visually/proprioceptively for both groups of children. These results question the conclusion that intra-modal will always be more accurate than inter-modal matching. When the combined scores for both hands were analyzed, the HECP children showed inferior performance to the control children in both inter- and intra-modal matching. Separate right and left hand analyses, demonstrated that the differences between the HECP group and control children could be accounted for by lowered performances when the right hand (nonpreferred) was used to match the located target position. Putative neurological disorders related to the development of the hemisphere controlling the nonpreferred hand (left hemisphere) are invoked to account for the poor performance with the nonpreferred hand of the HECP children.