How does meaning specificity affect adults' and children's verb learning and extension

Although verbs are in general more difficult to learn than nouns (e.g., Fenson et al., 1994), children's early vocabularies do contain some verbs (e.g., Fenson et al, 1994). Furthermore, some nouns (e.g., idea) are even harder to learn than some verbs (e.g., drinking). Finally, children's early vocabularies contain a much higher proportion of verbs in Chinese than in English (e.g., Tardif et al., 2008). To reconcile both the cross-linguistic noun advantage and the relative verb advantage in Chinese children's vocabularies, this dissertation has examined whether imageability (a word's capability to generate a mental image) could explain these findings in a unified way. Chapter 2 suggests that the cross-linguistic noun advantage may be due to the high imageability of early nouns. Additionally, early-acquired verbs also tend to be highly imageable. Furthermore, Chinese children's relative verb advantage may be related to the high imageability of early Chinese verbs. By experimentally testing one factor (meaning specificity) that could contribute to high imageability, Chapter 3 suggests that high imageability may facilitate children's verb fast-mapping but hinder verb extension. Chapter 4 shows that children's understanding of familiar verbs with specific meanings is restricted, thus, supporting the experimental finding that high imageability hinders verb extension.