Planning of an interceptive movement in children.

In the present study, we examined the spatio-temporal organization of the walking and reaching behaviour during an interception task in younger (6-9 years old) and older (10-13 years old) children. To this end, eighteen children had to walk towards an interception point to grasp a moving ball under three visual manipulation conditions. Walking and reaching behaviour were analysed during a condition allowing full vision of the ball trajectory and during two conditions in which vision towards the ball was partly occluded (enhanced planning requirement). The velocity of the ball was adapted to 50 or 70% of the maximum walking velocity of the participant. Results revealed that both younger and older children show a less accurate performance when the ball trajectory was occluded, while the walking profile and timing of the reach was not influenced by the occlusion manipulations. The findings seem to suggest that both groups were less accurate when the necessity of planning was enhanced.