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THE MUTUAL EXCLUSIVITY AND N3C PRINCIPLES: WHICH ONE IS HONORED FIRST?

Ilana Frank, Diane Poulin-Dubois, and Maxime Gagnon

Centre for Research in Human Development, Department of Psychology, PY-170, Concordia University, 7141 Sherbrooke St. West, Montreal, Quebec, H4B lR6, Canada

In learning new words, children seem to rely on several assumptions about word meanings to narrow down the set of plausible meanings for a novel word. One way to constrain word meanings is to assume that every object has only one name, i.e., to operate under an assumption of mutual exclusivity (ME) (Markman, 1992; Markman & Wachtel, 1988). Another principle, the novel name-nameless category (N3C) principle, states that novel words map to objects for which the child does not already have a name (Golinkoff et al., 1994; Mervis & Bertrand, 1994). Research on children under the age of three years has frequently confounded these two principles and has yielded inconsistent evidence. The present study compared performance on tasks designed to distinguish between ME and N3C in order to test the prediction that ME and N3C are two distinct principles that emerge at different stages of lexical development. A group of 19 monolingual English- and French-speaking children aged 27 months were administered an N3C task and a ME task within the same session. Overall, children were successful on more mapping trials of the N3C task than of the ME task. In addition, a greater number of subjects failed the ME task but succeeded on the N3C task than succeeded on the ME task but failed on the N3C task. The present findings suggest that the ME and N3C principles can be teased apart experimentally and that the N3C principle appears to be honored before the ME principle.