Mapping Words to the World in Infancy: Infants' Expectations for Count Nouns and Adjectives

Three experiments document that 14-month-old infants' construal of objects (e. g., purple animals) is influenced by naming, that they can distinguish between the grammatical form noun and adjective, and that they treat this distinction as relevant to meaning. In each experiment, infants extended novel nouns (e. g., "This one is a blicket") specifically to object categories (e. g., animal), and not to object properties (e. g., purple things). This robust noun-category link is related to grammatical form and not to surface differences in the presentation of novel words (Experiment 3). Infants' extensions of novel adjectives (e. g., "This one is blickish") were more fragile: They extended adjectives specifically to object properties when the property was color (Experiment 1), but revealed a less precise mapping when the property was texture (Experiment 2). These results reveal that by 14 months, infants distinguish between grammatical forms and utilize these distinctions in determining the meaning of novel words.