Tracking by young infants.
D000367:Age Factors; D002657:Child Development; D004192:Discrimination, Psychological; D005133:Eye Movements; D005403:Fixation, Ocular; D006801:Humans; D007223:Infant; D009039:Motion Perception; D013997:Time Factors; D014792:Visual Acuity; D014796:Visual Perception