Planning an Action: A Developmental Progression in Tool Use.

How children pick up a tool reveals their ability to plan an action with the end goal in mind. When presented with a spoon whose handle points away from their dominant hand, children between infancy and 8 years of age progress from using an awkward ulnar grip that causes food to spill from the spoon to consistently using a radial grip. At 4 years of age children's grip strategies are highly variable, including the awkward grips of infancy and use of the non-dominant hand, but they also employ adult-like grips never seen in infancy. By 8 years of age the infantile ulnar grip has completely disappeared and is replaced by more mature and effective grips that indicates better planning for the end goal.