Lexical Development.

The question of how children master impressive quantities of words at an early age has received scant attention from the language development literature. A small body of literature has demonstrated that children as young three can take advantage of linguistic context to learn new words, and at least one study suggests that even two-year olds can do so. The current study explored early lexical development by examining how linguistic sophistication (determined by the early stages of word learning described in the literature) affected children's ability to take advantage of different linguistic contexts. Children at four levels of productive language ability were exposed to nonsense labels for novel animals in a picture book. In a within-subject design, six conditions determined the linguistic context with which each label/animal pair was presented: (1) Simple (label only); (2) Fixed ("That's a "); (3) Article (article plus label); (4) Question ("Is that a "?); (5) Mixed (conditions 2-4); (6) Control (no label). Three post-tests each were administered on two different days (S1 and S2) testing: (1) production; (2) comprehension of stimuli highly similar to the book pictures; (3) comprehension of stimuli less similar to the pictures. Learning from input was demonstrated by all sophistication groups comprehending above chance overall. Data also showed a curvilinear relationship between comprehension and language sophistication. Comprehension performance was significantly lower in the Control Condition, tended to be higher in the Article Condition on High Similarity and Session 1 tests, and was higher in the Mixed Condition on Low Similarity tests. There was no overall difference between S1 and S2 comprehension, reflecting substantial retention. Production data suggested a facilitative role for the Mixed Condition. There was no statistically significant comprehension/production correspondence, but descriptive data suggested a complex relationship. An interactive developmental framework was proposed to account for the findings. Language group differences were explained in terms of the allocation of cognitive resources. The data were interpreted as suggesting that given input conditions affect the level at which information is stored in memory. Comprehension/production data suggested that further research is needed to elaborate the relationship between these skills. Directions for future research motivated by this exploratory study were discussed.PhDDevelopmental psychologyUniversity of Michiganhttp://deepblue.lib.umich.edu/bitstream/2027.42/159822/1/8402367.pd