Infant learning ability for recognizing artificially-produced 3D objects

摘要

??Regardless of changes in viewpoint, observers can recognize objects from almost any direction. Experiencing objects from various viewpoints may enhance the development of this ability. Previous study has shown that 6- to 8-month old infants who were presented with sequentially rotated face images from profile to frontal view could identify the learned face (Nakato et al., 2005). Since faces are special objects for infants, it may be possible that such ability is limited to facial recognition. Here, we investigate the differences in infant learning ability for faces and objects. To investigate such 3D object recognition, we designed images which were well controlled in both their texture and color. Objects were created using three-dimensional graphic software (Shade 9 Professional; e-frontier, Inc., Japan, Poser 7; Smith Micro software, Inc., California). One hundred and twelve sequential images of each object were created by rotating an axis perpendicular to the visual axis connecting the viewera??s eyes and the object from frontal view to plus-minus 60 deg. 3- to 6-month-old-infants participated in the present study, and a familiarizationovelty preference procedure was used to investigate infantsa?? 3D object recognition. Infants were first familiarized with a face image (face image condition) or a shoe image (shoe image condition). During the familiarization phase, infants were repeatedly shown sequentially rotating images of a face or a shoe for 15 sec ?? 6 trials. After familiarization, we checked infantsa?? novelty preference between these two conditions. In the test phase, infants were shown the familiarized face (or a shoe) and a novel face (or a shoe) side by side for 10 sec ?? 2 trials. Our preliminary results showed that the ability for face learning matures earlier than that for object leaning. This result suggests that the face is a special object for infants even in artificially-produced 3D object recognition.