Acoustic correlates of the question–statement contrast in children

Abstract

The acoustics of prosodic control in children was studied in 4-, 7-, and 11-year olds using the question–statement contrast. Each child produced the utterances ‘‘Show Bob a bot’’ (voiced consonants) and ‘‘Show Pop a pot’’ (voiceless consonants) ten times each as a question and ten times each as a statement. A total of 40 utterances were analyzed per child. The following acoustic measures were obtained for each word within each utterance: average fundamental frequency (f0), peak f0, slope of f0, average intensity, peak intensity and duration. Preliminary results indicate no significant difference between questions and statements for 4-year olds in both the voiced and voiceless consonant conditions. In contrast, 7- and 11-year olds differentiated questions from statements by increasing average, peak, and slope of f0 as well as increasing the duration of the final syllable. Changes in syllable duration between questions and statements were more pronounced for the utterance with voiced consonants. These findings suggest that the acoustics of prosodic contrasts begins to differentiate somewhere between ages 4 and 7 and is influenced by developmental changes in physiological control and flexibility which may also affect segmental features.