We examined the developmental differences in motor control and learning of a two-segment movement. One hundred and five participants (53 female) were divided into three age groups (7-8 years, 9-10 years and 19-27 years). They performed a two-segment movement task in four conditions (full vision, fully disturbed vision, disturbed vision in the…

To harness the complexity of their high-dimensional bodies during sensorimotor development, infants are guided by patterns of freezing and freeing of degrees of freedom. For instance, when learning to reach, infants free the degrees of freedom in their arm proximodistally, that is, from joints that are closer to the body to those that are more…

In executing purposeful actions, adults select sufficient and necessary limbs. But infants often move goal-irrelevant limbs, suggesting a developmental process of motor specialization. Two experiments with 9- and 12-month-olds revealed gradual decreases in extraneous movements in non-acting limbs during unimanual actions. In Experiment 1,…