Static and dynamic visuomotor task performance in children with acquired brain injury : predictive control deficits under increased temporal pressure

Objective: To compare performance of children with acquired brain injury (AB I) on static versus dynamic visuornotor tasks with that of control children. Participants: Twenty-eight children with ABI and 28 normal age- and gender-matched controls (aged 6-16 years). Main Measures: Two visuornotor tasks on a digitizing tablet: (1) a static motor task requiring tracing of a flower figure and (2) a dynamic task consisting of tracking an accelerating dot presented on a monitor. Results: Children with ABI performed worse than the control group only during the dynamic tracking task; the duration within the target was shorter, the distance between the centers of cursor and target was larger, and the number of velocity peaks per centimeter and the number of stops (ie, the number of submovements) were higher than those of the control group. Rather than resulting from movement execution problems, this might be due to less adequate processing of fast incoming sensory information, resulting in a decreased ability to anticipate the movement of the target (predictive control). Conclusion: Deficits in eye-hand coordination require careful attention, even in the postinjury chronic phase