Perception of Object Length Via Manual Wielding in Children With and Without Developmental Coordination Disorder.

The authors compared haptic perception via active manual wielding in children with and without developmental coordination disorder (DCD). Forty-eight children, 11-12 years old, participated as volunteers. Twenty-four were typically developing children (TDC), and 24 had been diagnosed with DCD. Individually, children held and wielded unseen rods of five lengths (20, 45, 60, 75, or 90 cm). Based on this wielding, children judged the length of each rod. Judgments of rod length were shorter in the DCD group than in the TDC group. In addition, significant interactions revealed that the difference between the 2 groups was progressively greater for longer rods. The results provide support for the hypothesis that DCD includes deficits in the ability to use manual wielding in the perception of object length. In addition, the results suggest that the deficit is not general, but is greater for longer objects.