Developmental change in form categorization in early infancy

Three experiments utilizing the familiarization/novelty-preference procedur e were conducted to examine the form categorization abilities of newborn an d 3- to 4-month-old infants. In the first two experiments, newborn infants discriminated between individual exemplars chosen from different form categ ories (Expt 1) and from within a form category (Expt 2). In Expt 3, older i nfants provided evidence of having formed individuated categorical represen tations for circles, crosses, squares and triangles, whereas newborn infant s did not. However, newborn performance was consistent with the formation o f broader categorical representations for open versus closed classes of for m (i.e. crosses vs, circles, squares and triangles). The results are discus sed in terms of a possible differentiation-based developmental change from broad-to-narrow (or global-to-basic) in the perceptual category representat ions formed by young infants.