On 8 April 2019 Mengru Han MA (Linguistics) will defend her PhD thesis The role of prosodic input in word learning. A cross-linguistic investigation of Dutch and Mandarin Chinese infant-directed speech at the University Hall.
Children learn new words by interacting with their caregivers. When talking to children, mothers around the world use a speaking style known as baby talk or infant-directed speech, which is characterized by exaggerated prosody as compared to adult-directed speech.
Prosody is the patterns of stress and intonation in a language. So far, the role of infant-directed speech prosody in early word learning has not been fully understood. This dissertation investigates the role of prosodic input in children’s word learning. This is achieved by focusing on infant-directed speech in word-learning contexts in which mothers introduce unfamiliar words to their children.
This study took a cross-linguistic approach to examine infant-directed speech in two typologically distinct languages: Dutch and Mandarin Chinese. A semi-spontaneous storybook-telling task was used to elicit both adult-directed speech and infant-directed speech from mothers of 18- and 24-month-old children. Also, a word-learning experiment was conducted to evaluate children’s online word-to-object mapping performances when hearing adult-directed speech or infant-directed speech.
Three key findings emerged. First, both Dutch and Chinese mothers are sensitive to their children’s vocabulary knowledge and adapt their speech prosody accordingly in word-learning contexts. However, infant-directed speech prosody in word-learning contexts is manifested differently across languages. Second, the prosody of Dutch infant-directed speech specific to word-learning contexts is significantly correlated with children’s vocabulary size and vocabulary growth. Third, Dutch 24-month-old children can reliably learn novel words from both adult-directed speech and infant-directed speech, but infant-directed speech has a small facilitative effect on children’s online word learning compared to adult-directed speech. In conclusion, prosodic input in word-learning contexts is fine-tuned for linguistic purposes and plays a significant role in children’s word learning.
On the occasion of this event, on the morning of 8 April, there will be a workshop on 'Infant-directed Speech in Early Language Acquisition'. More information.