Individual differences in 4-year-old children's acquisition of vocabulary during storybook reading.

Two experiments were conducted to assess how children who differ in vocabulary knowledge learn new vocabulary incidentally from listening to stories read aloud. In both experiments, 4-year-old children were classified as having either high or low word knowledge on the basis of a median split of their Peabody Picture Vocabulary Test-Revised (PPVT-R) standard scores. In Experiment 1, children either listened passively or labeled pictures using novel words during the book readings. We found that children with larger vocabularies produced more novel words than did children with smaller vocabularies, and children who answered questions during the book readings comprehended and produced more words than did children who passively listened to the story. In Experiment 2, children either listened to readings of a book, pointed to pictures during the readings, or labeled pictures during the readings. Children with larger vocabularies comprehended more novel words than did children with smaller vocabularies. Children who actively participated by labeling or pointing learned more words than did children who listened passively to book readings. The findings clarify the role of active responding by demonstrating that verbal and nonverbal responding are effective means of enhancing vocabulary acquisition