Infants' response to pictures of impossible objects
Sarah Shuwairi, Lehman College, CUNY
Perceiving objects and scenes as coherent in three dimensions (3D) is a fundamental ability of the mature visual system. How and when the mechanisms supporting coherent 3D object processing arise in early development have been central topics of research and discussion. Moreover, the question of whether young infants would respond differently to pictures of incoherent ("impossible") objects relative to coherent ("possible") ones was undocumented until recently. In our original study, we used a looking-time paradigm to examine whether 4-month-olds could differentiate between possible and impossible cube displays. Infants looked significantly longer at pictures of impossible objects relative to possible ones, which suggests that very young infants are sensitive to line junction information (e.g., T-junction cues) in the context of perceiving global shape. These findings established that perceptual mechanisms involved in deriving 3D structural information from binding edges and critical line junctions in static images are available within the first few postnatal months, but left open the question of how infants are able to distinguish between pictures of possible and impossible objects. This presentation will highlight data suggesting that the infant's visual system extracts critical structural information contained in 2D images in an attempt to analyze the projected 3D configuration, and that this information serves to control both oculomotor and manual action systems. The findings help clarify the development of mechanisms for processing pictorial depth cues and extracting information about 3D structure from pictures of objects. This work also provides further insights into the development of infants' conceptual knowledge of coherent 3D objects, i.e., the ability to perceive and understand objects in the world around them and the ability to act appropriately toward both real and depicted objects.