title: Size constancy in infants: 4-month-olds' responses to physical versus retinal image size.
abstract: This study tested whether 4-month-old infants respond primarily to objects' physical or retinal image sizes. In the study's main experiment, infants were habituated to either a 6-cm-diameter disk at a distance of 18 cm or a 10-cm disk at 50 cm. They were then given 2 test trials in which the 6- and 10-cm disks were presented side by side at a distance of 30 cm. For each infant, one test object had a novel physical size but a familiar retinal image size, and the other had a familiar physical size but a novel retinal image size. The infants exhibited a significant looking preference for the object that had a novel physical size. A preliminary experiment found that 4-month-olds' looking preferences are based on novelty, not familiarity, under the conditions of this study. Given this finding, the results suggest that 4-month-old infants attend and respond primarily to physical size, not to retinal image size.
authors.affiliation: School of Psychological Sciences, University of Northern Colorado, Greeley, CO 80639, USA. carl.granrud@unco.edu
authors.forename: Carl E
authors.initials: CE
authors.lastname: Granrud
mesh_terms: D001288:Attention; D002657:Child Development; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D002666:Psychology, Child; D012160:Retina / Q000502:physiology; D012858:Size Perception / Q000502:physiology*; D013028:Space Perception / Q000502:physiology