Adaptation to visual distortion in motor coordination in childhood

The aim of the experiment was to study the adaptive capacities of children to perform drawing movements while being visually perturbed. Children aged 5 to 11 (N = 47) and a group of adults (N = 10) drew diamonds via information provided through a computer screen. The screen display was either upright or rotated 180°. The absence of direct vision of the hand yielded more perturbation in the youngest group of children compared to all other groups. In spite of some initial difficulty, all children reached good control after 5 trials on the task. When faced with spatial rotations of the visual field, youngsters were again more perturbed than others. All children showed the same rate of adaptation to visual rotations, but they differed on adoptive strategies. Five- and 7-year olds shifted to a feedforward mode of control consisting in the production of a rapid gesture, followed by error evaluation in order to correct their next movement. Older children were characterised by a progressive integration of re-afferent visual and proprioceptive information. This resulted in an increase in duration of strokes and reduced speed, meaning enhanced on-line retrieval of information. However, nine-year-old children experienced more difficulty recuperating sensory information during movement than 11-year olds, and kept using error feedback. Finally, visuo-manual coordination in children aged 11, while only slightly differing from that of adults, was not yet totally mature.