Prospective control in catching by infants.
Catching a moving object requires the ability to predict the future trajectory of the object. To test whether infants can use visual information predictively, reaching for a toy moving at different speeds was investigated in six infants around 11 months of age. The toy was occluded from view by a screen during the last part of its approach. Gaze arrived at the exit side of the screen and the hand started to move forward before the toy had disappeared behind the occluder; these actions were prospectively geared to certain times before the toy would reappear. In addition, hand-movement duration was found to be related to the time of reappearance of the toy--the information used to regulate duration of hand movement being picked up before the toy disappeared behind the occluder. In a longitudinal experiment, the development of predictive reaching was investigated in two infants between the ages of 20 and 48 weeks. At all ages studied, gaze anticipated the reappearance of the moving toy. However, anticipation with hand movement of the disappearance of the toy and the ability to gear actions prospectively to the time (instead of distance) the toy was away from certain points on the track developed relatively late and marked the transition to successfully catching faster-moving toys.
Department of Psychology, University of Edinburgh, UK.
A L
AL
van der Meer
F R
FR
van der Weel
D N
DN
Lee
D000054:Acceleration; D000367:Age Factors; D001288:Attention; D004215:Distance Perception; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009039:Motion Perception; D009949:Orientation; D010470:Perceptual Masking; D002666:Psychology, Child; D011597:Psychomotor Performance; D011930:Reaction Time