The cradle of categorization: Is the basic level basic?

Abstract

A common assumption in the developmental literature is that the earliest kind of conceptual categories to be formed are basic-level categories. A corollary assumption is that superordinate categories are formed after, and out of, previously acquired basic-level categories. Two experiments using an object-manipulation task explored these assumptions by studying response to a variety of categories in children aged from 12 to 20 months. The first experiment examined responses to basic-level categories (dogs vs. cars),superordinate categories (animals vs. vehicles), and contextual categories (kitchen things vs. bathroom things). At all ages tested, the children performed best on the basic-level categories but, even at 12 months of age, some children were responsive to the superordinate and contextual categories. By 20 months of age, approximately half of the children showed such sensitivity. The second experiment showed that 16- and 20-month-olds differentiated basic-level categories only when the categorical contrasts were taken from different superordinate classes (e.g., dogs vs. cars) and not when the categories were drawn from the same superordinate class (e.g., dogs vs. horses). The data suggest that basic-levels categories are not the first kind of conceptual categories to be formed. Instead, it appears that children may form more global categories, with basic-level differentiation occurring later.