Stages of Child Development Festschrift

Previous work has demonstrated that infants use object trajectory continuity as a cue to the constant identity of an object, but results are equivocal regarding the role of object features, with some work suggesting that a change in the appearance of an object does not cue a change in identity.  In an experiment involving 72 participants we investigated the effects of changing object shape and color, singly and in combination, on 4-month-olds’ perception of object continuity. A change in the shape of an object while it passed behind an occluder had no effect on perception of continuity, whereas a change in shape and color led to perception of discontinuity, and a change in color led to no clear percept regarding continuity or discontinuity.  These results are discussed in terms of a perceptual learning model of development of object identity. (Bremner, J. G., Slater, A. M., Mason, U. C., Spring, J., & Johnson, S. P.  (in press).  Trajectory perception and object continuity:  Effects of shape and color change on 4-month-olds’ perception of trajectory identity.  Developmental)

We investigated oculomotor anticipations in 4-month-old infants as they viewed center-occluded object trajectories. In two experiments, we examined performance in 2D and 3D dynamic occlusion displays, and in an additional 3D condition with a smiley face as the moving target stimulus. Rates of anticipatory eye movements were not facilitated by 3D displays or by the (presumably) more salient smiley face relative to the 2D condition. However, latencies of anticipations were reduced, implying that 3D visual information may have supported formation of more robust mental representations of the moving object. Results are interpreted in a context of perceptual constraints on developing cognitive capacities in early infancy. (Johnson, S. P., Bremner, J. G., Slater, A. M., Shuwairi, S. M., Mason, U., Spring, J., & Usherwood, B. (2012). Young infants' perception of the trajectories of two- and three-dimensional objects. Journal of Experimental Child Psychology, 113, 117-185.)