Integration of dynamic information for visuomotor control in young adults with developmental coordination disorder.

We examined the hypothesis that developmental coordination disorder (DCD) consists of a poor integration of distal preparatory visual information with the visual information that arises during movement execution. We set up a steering task where the action goal was to steer smoothly on a virtual winding course under conditions that manipulated the availability and timing of visual information. Participants were 20 young adults who had been diagnosed with DCD in their childhood and 20 typically developing age-matched controls. On a simple tracking task, participants with DCD were slower and more variable than controls. The group differences dissipated, however, when the display highlighted the directional changes necessary within the next 500 ms. When the latter condition was modified to also include the full layout of the course, however, the performance of the DCD group once again decreased. This result could not be attributed to a simple distraction effect. The results suggest that distinct neural mechanisms are associated with the processing of fast visual information for online control and longer-term action preparation based on spatial layout. In skilled action, cerebellar and parietal areas process information effectively and their outputs are integrated into one smooth movement. Because the DCD group showed difficulties in steering when both types of information were present, it is likely that this integration is suboptimal.