Effects of motion and figural goodness on haptic object perception in infancy.

4-month-old infants held 2 rings, 1 in each hand, out of view. The rings moved rigidly together and were either the same (Experiment 1) or different (Experiment 2) in substance, weight, texture, and shape. After haptic habituation to a ring display, patterns of preferential looking to visibly connected vs. separated rings provided evidence that the infants perceived the rings in both experiments as parts of one connected object. This perception was no weaker when the rings differed in shape and substance, even though infants were shown (Experiment 3) to detect that difference. In the haptic mode, as in the visual mode, infants appear to perceive object unity by analyzing motion but not by analyzing figural goodness. The findings suggest that an amodal mechanism underlies object perception.