Early Acquisition of Nouns and Verbs Evidence from Navajo

W hich words do children learn earliest, and why? These questions bear on the developmental origin of language and its connection to thought. The striking dominance of nouns in early English vocabularies has led researchers to ask whether there is something special about the link between nouns and concrete objects (e. proposed a conceptual explanation for this early noun dominance: The mapping between words and experience is easier for nouns because of the greater perceptual learnability of their referents in children's early experience. Gentner proposed two interrelated hypotheses concerning learnability: the natural partitions hypothesis and the relational relativity hypothesis. The natural partitions hypothesis states that concrete objects and entities are easier to indi-viduate in the world (and therefore easier to label) than are the relational constellations that form the referents of verbs or prepositions (Gentner, 1981, 1982; Gentner & Boroditsky, 2001). This is in part a specic case of a general pattern referred to as the relational shift in cognitive development (Gentner, 1988; Halford, 1992). Relations require the presence of the entities they link; thus it appears that entities are psychologically represented before the relations between them. For example, young children given a similarity task often respond according to object similarity , even when they are given repeated feedback that the correct response should be based on relational similarity. In contrast, older children can readily focus on Further, there is evidence that in adult encoding of scenes, object attributes are encoded before the relations between them (Sloutsky & Yarlas, in preparation). The early object advantage in part reects this priority of entities over the relations between them. But another contributor to the object advantage is relational relativity. The relational relativity hypothesis states that verb meanings are more variably composed across languages than are noun meanings—that is, relational terms such as verbs and prepositions vary crosslinguistically in their meanings to a greater degree than do concrete nouns. Because objects are readily individuated in the world, the denotations of concrete nouns can be derived by linking a word with an existing concept. But the meanings of verbs and prepositions (even in concrete perceptual arenas) are not " out there " in the same sense. This means that children cannot learn verbs from the word-to-world mapping alone; they must discover how their particular language chooses to combine the elements of experience into verb meanings. A related approach has been taken by Markman (1989) …