Abstract
The purpose of this study was to explore the development of the infants' ability to perceive 3D shape from pictorial depth cues. The method investigated whether spatial information provided by one depth cue was available when the infant was presented with a novel and familiar layout provided by a different depth cue. (Yonas, Arterberry & Granurd, 1987; Yonas & Pick, 1975). Previous studies used habituation (Imura et al., 2006, 2008; Kavsek, 1999) and preferential looking methods (Bertin & Bhatt, 2006; Bhatt & Bertin, 2001; Bhatt & Waters, 1998), however, these methods did not provide clear evidence that infants perceived the 3D shape of the stimuli. While these methods allow us to infer that infants can discriminate between displays, they do not rule out the possibility that infants discriminate between the proximal stimuli but not the distal stimuli. To rule out this possibility and examine infants' ability to perceive 3D shape from pictorial depth cues, we employed a “transfer-across-depth-cues” method. In this method, we examined the transfer between two pictorial depth cues: shading and surface contours. Infants were habituated to a 3D shape specified by one cue, and then presented with the same shape and a novel-shape, both specified by the other depth cue. In this case, infants could distinguish the familiar shape and the novel shape only if they perceive 3D shape from the pictorial depth cues, despite the shift in the type of the pictorial cues. Results indicate that six-to-seven-month-old infants showed a significant novelty preference despite the shift in the type of the pictorial cue. On the other hand, four-to-five-month-old infants did not. The results clearly indicate a significant improvement in responsiveness to the pictorial cues between the younger and the older age group.
This research was supported by PRESTO (Japan Science and Technology Agency) and a Grant-in-Aid for Scientific Research (18300090, 20119002, 20539004) from Japan Society for the Promotion of Science.