Neuromotor deficits in developmental coordination disorder: evidence from a reach-to-grasp task.
Kids with DCD open the hand too wide and slow—test reach-to-grasp with and without vision to spot the visuomotor gap.
01Research in Context
What this study did
Biancotto et al. (2011) watched kids with Developmental Coordination Disorder pick up a toy block.
They compared the reach-to-grasp moves to same-age kids without motor trouble.
The team filmed finger opening, speed, and wobble with and without vision.
What they found
Kids with DCD opened their fingers wider and moved slower.
Their timing was jumpy, especially when they could not see their hand.
The wider, shaky grip shows the brain’s inner model of the object is off.
How this fits with other research
McGarty et al. (2018) saw the same slow, wide moves in kids with hemiplegic CP.
They added eye-tracking and found late looking starts the problem.
Together the papers say: fix the eyes first, then the hand will speed up.
Matson et al. (2009) looked at grip force, not finger width.
They found kids with profound ID can scale force but still wobble on light objects.
So both width and force errors live in different brain loops—check both.
Why it matters
Next time a child with DCD drops items, run a quick reach-to-grasp probe.
Dim the lights or cover the hand to see if vision guides the grip.
If the move falls apart, add short eye-shift warm-ups before fine-motor work.
Want CEUs on This Topic?
The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.
Join Free →Place a small block on the table, cover the child’s hand with a cloth, and count how many tries it takes to pick it up smoothly—then repeat with vision and compare.
02At a glance
03Original abstract
Developmental coordination disorder (DCD) has been classified as a specific learning disability, nonetheless the underlying cognitive mechanisms are still a matter of discussion. After a summary of the main hypotheses on the principal neuromotor causes of DCD, this study applies a causal model framework to describe the possible coexistence of more than one deficit in this disorder. For this purpose, kinematic analysis was applied to an ecological task, the reach-to-grasp action, introducing the manipulation of three variables: vision, distance and object size. After a thorough neurological and neuropsychological evaluation, 9 children with DCD (7-9 years old) were selected and compared to 27 age-matched control children. The results suggest that children with DCD have a normal neurological characterization of the reaching and grasping movements, in terms of proximal to distal action, but their grasping aperture (MGA) was always wider with respect to controls, particularly when vision was not allowed. In addition, the performance of children with DCD was always slower, more dependent on vision and more variable than that of controls. The MGA of children with DCD could be explained by a deficit in the internal construction of movement for a forward model, while slowness could be related to a control problem in the neuronal firing of the muscles. The idea of a possible coexistence of these two deficits is discussed in accordance to a causal model framework and also addressed considering recent neurophysiologic evidences.
Research in developmental disabilities, 2011 · doi:10.1016/j.ridd.2011.02.007