Preference for impossible figures in 4-month-olds.

Can infants use interposition and line junction cues to infer three-dimensional (3D) structure? Previous work has shown that in a task that required 4-month-olds to discriminate between static two-dimensional (2D) pictures of possible and impossible cubes, infants exhibited a spontaneous preference for displays of the impossible cube but left open the question of whether they did so on the basis of purely local "critical regions" or whether they were able to employ more global clues. Here infants were presented with possible and impossible cubes in which the strictly local cues that could have derived from exterior binding contours were deleted. Results showed that infants were still able to discriminate possible cubes from impossible cubes, suggesting that longer looking infants are sensitive to global properties and that the capacity to integrate pictorial information to perceive aspects of global 3D shape may develop earlier than demonstrated previously using reaching tasks.