STUDIES ON THE FORMATION OF PERCEPTUALLY BASED BASIC-LEVEL CATEGORIESIN YOUNG INFANTS

A series of experiments examined the abilities of 3- and 4-month-old i nfants to form categorical representations to exemplars of natural kin ds-cats and horses. These experiments also permitted assessment of the relative exclusivity of these representations-the extent to which the y exclude exemplars from contrasting basic-level categories from the s ame superordinate category. We found that categorical representations could be formed for horses that excluded cats, zebras, and giraffes, a nd for cats that excluded horses and tigers but not female lions. Lion s were, however, excluded from the representations of cats in 6- and 7 -month-old infants. Evidence was also obtained for 2 a priori preferen ces for members of one category over another. The discussion examined the roles of similarity between the exemplars of the contrasting categ ories and those of the tested category on estimates of exclusivity and of spontaneous preferences on the formation and exclusivity of catego rical representations.