Utterance-Initial Prosodic Differences Between Statements and Questions in Infant-Directed Speech

Cross-linguistically, statements and questions broadly differ in syntactic organization. To learn the syntactic properties of each sentence type, learners might first rely on non-syntactic information. This paper analyzed prosodic differences between infant-directed wh-questions and statements to determine what kinds of cues might be available. We predicted there would be a significant difference depending on the first words that appear in wh-questions (e.g., two closed-class words; meaning words from a category that rarely changes) compared to the variety of first words found in statements. We measured F0, duration, and intensity of the first two words in statements and wh-questions in naturalistic speech from 13 mother-child dyads in the Brent corpus of the CHILDES database. Results found larger differences between sentence-types when the second word was an open-class not a closed-class word, suggesting a relationship between prosodic and syntactic information in an utterance-initial position that infants may use to make sentence-type distinctions.