Motor and cognitive dual-task performance under low and high task complexity in children with and without developmental coordination disorder

Background. In everyday life, tasks are often performed simultaneously, which may be more difficult for children with developmental coordination disorder (DCD) than their peers. Aims. To examine (1) the effects of task complexity and type of concurrent task on dual-task performance in children with and without DCD; and (2) if the amount of effort that children put into the task performance differs between the groups. Methods. Participants were 64 children with and without DCD (aged 7–14 years). The dual-task paradigm consisted of a manual dexterity task of relatively low complexity (box and block test) or relatively high complexity (pegboard task), and a concurrent motor task (cycling task) or a concurrent cognitive task (word-listening task). To assess mental effort, children were asked how tired they felt before and after the experiment. Results. Dual-task interference was highest when the manual dexterity task of relatively high complexity was combined with the concurrent motor task. There were no group differences in dual-task interference, but children with DCD reported a larger increase in the level of tiredness after the experiment indicative of greater mental effort. Conclusions. Depending on task demands, children with DCD are able to perform dual-tasks at the same level as their peers, but performance may take children with DCD more mental effort.