Abstract

The purpose of the current thesis was to explore the mechanisms involved in children's early word learning. In the first paper, the issue of cross-linguistic word learning was examined. The question of interest was whether the type of language a child is acquiring influences his or her interpretation of a novel label for an event. The study sought to test whether children acquiring languages that emphasize more nouns or more verbs, would be guided by their linguistic input, in their interpretation of a label for an object in motion. An infant-controlled habituation paradigm was used to teach two labels for two different events to children acquiring English, French, and Japanese. English and French place a greater emphasis on nouns, whereas Japanese tends to emphasize verbs. Eighteen- to 20-month-olds' interpretation of this event was tested using a switch design, where the original label-object-motion combination was manipulated. Despite differences in the children's linguistic input, both groups of children interpreted the object as being the referent of the novel label. The second paper further explored the nature of children's word-event associations, by its relationship with other standard word-learning measures. Towards this purpose, English- and French-speaking children who had participated in the first experiment at the age of 18 months were invited into the laboratory at 24 months to participate in a standard fast-mapping task. The relationship between children's performance on the habituation task at 18-months and their performance on the fast-mapping task at 24-months was examined. Furthermore, the relationship between children's performance on both tasks and their concurrent and longitudinal vocabulary was also explored. Eighteen-month-olds' ability to form a word-event association was related to their comprehension of familiar words at 24 months. Furthermore, the data also suggested that children's ability to form a word-object association was related to their vocabulary size at 18 and 24 months. These findings emphasize the continuity in children's word-learning abilities as measured by different experimental procedures. Together, these two papers highlight the role of cognitive and perceptual factors in early word learning, and also emphasize the underlying continuity in children's word-learning