Constraints children place on word meanings

Abstract

This paper views lexical acquisition as a problem of induction: Children musl figure out the meaning of a given term, given the large number of possible meanings any term could have. If children had to consider, evaluate, and rule out an unlimited number of hypotheses about each word in order to figure out its meaning, learning word meanings would be hopeless. Children-must, therefore, be limited i n the kinds of hypotheses they consider as possible word meanings. This paper considers three possible constraints on word meanings: (1) The whole object assumption which leads children to interpret novel terms as labels for objects -not parts, substances, or other properties of objects: (2) The taxonomic assumption which leads children to consider labels as referring to objects of like kind, rather than to objects that are thematically related: and (3) The mutual exclusivity assumption which leads children to expect each object to have only one label. Some of the evidence for these constraints is reviewed. This paper is based on a talk given in the symposium Structural Constraints on Cognitive Development, Psychonomics, 1986 and borrows heavily from Markman (in press). This work was supported in part by NIH Grant HD 20382. I would like to thank Roche1 Gelman, Douglas Medin, Steven Pinker, and Elizabeth Spelke for their thoughtful comments on this manuscript.Correspondence and requests for reprints should be sent to Ellen M. Markman, Psychology

At 6–9 months, human infants know the meanings of many common nouns

“…This association-based kind of account would explain our results by appealing to infants' ability to track consistent features of their physical environment when hearing words, progressively hypothesis testing (with or without an active intent to learn) until the referents of the words were isolated. In considering this hypothesis, we note that many of our target words did not refer to distinct, bounded objects, which have been suggested as good defaults for such hypotheses (35). Infants here performed well across an array of items containing well-delineated objects (e.g., cookie, bottle), amorphous substances (e.g., milk, juice), and unclearly bounded body parts (e.g., nose, hands) (see Fig.…”

Infants rapidly learn word-referent mappings via cross-situational statistics

“…Experimental studies leave no doubt that by the time they are 2 years old children do this at least for object names. That literature points to attentional (Smith, 2000), social (Baldwin, 1993;Tomasello, 2000), linguistic (Gleitman, 1990) and representational (Markman, 1990) constraints as crucial to children's ability to resolve referential ambiguity and fastmap a word to its intended referent.…”

“…There is evidence in such phenomena as the mutual-exclusivity effect and contrast that 2-to 3-year-old children combine information across two adjacent naming events, using, for example, knowledge of the just-heard name of one thing to infer the object to which a subsequent name must apply (Akhtar, 2002;Akhtar & Montague, 1999;Markman, 1990;Namy & Gentner, 2002. ) However, there is no evidence as to whether young learners can combine and evaluate information from highly ambiguous contexts over many trials.…”

Isolated and interrelated concepts

“…Another source oflinguistic evidence for competition between concepts comes from work on the mutual exclusivity hypothesis (Markman, 1990;Waxman, Chambers, Yntema, & Gelman, 1989). According to this work, children determine the referent of a noun by assuming that nouns are mutually exclusive, and consequently, ifa new term is applied to one of two objects, and if one of these objects already has a name, children will tend to assume that the term refers to the other object.…”