Influence of object spatial location and task complexity on children's use of their preferred hand depending on their handedness consistency.

The goal of the present study was to compare the use of the preferred versus the nonpreferred hand in children performing two tasks of different levels of complexity, in various positions in space. Right-handed and left-handed consistent children were compared to their inconsistent counterparts. The results showed that the general tendency to use one's preferred hand to grasp an object is more or less pronounced depending on the object's spatial location and the task's complexity. The children used their preferred hand more often even when the object was presented contralaterally, and did so to a greater extent during the more complex task. Inconsistent-handers were more likely to shift to using their nonpreferred hand when the object was presented to this hand's side. Finally, we found that the influence of handedness consistency on hand use for the spatial positions varied with the complexity of the task. These results favor a view of handedness as a dynamic process in which motor preferences interact with task demand, probably through task-related attention.