Development of motor imagery ability in children with developmental coordination disorder - A goal-directed pointing task.

Children with developmental coordination disorder (DCD) have difficulties with the predictive control of movements. This was shown in studies that target motor imagery and motor planning, and appears to become particularly evident with increases in task complexity. In this study, we used a complex mental chronometry paradigm to examine the development of motor imagery ability in children with DCD, using a longitudinal design. Thirty children were included in the DCD group (aged 6-11 years) and age- and gender-matched to 30 controls. The DCD group had a Movement Assessment Battery for Children-2 score ≤16th percentile and the control group ≥25th percentile. Results of this study showed that children with DCD indeed had a significantly lower correlation between executed and imagined movements. Importantly, the increase in the correlation and linear fit during subsequent measurements was comparable for the DCD and control group. Together, these findings suggest a delayed developmental onset of motor imagery ability in DCD, but a similar rate of development over time compared to the control group. Based on these results, it seems likely that explicit motor imagery instructions can be used to improve predictive control in children with DCD.