Prosodic Features in Child-directed Speech during the Child's First Year

This study investigates prosodic features of child-directed speech during the child’s first year, using the automated prosodic annotation software Prosogram. From previous studies on first language acquisition and child-directed speech we know that speech directed to infants and small children is characterised by exaggerated use of several prosodic features, including a higher pitch, livelier pitch movement and slower speech rate. Annotation of these phenomena has previously been done manually, which is time consuming and includes a risk of circularity. If we can use semi-automated systems to carry out this task, it would be a huge methodological gain. This study analysed recordings of 10 parent-child pairs at four occasions (3, 6, 9 and 12 months of age) for a total of 40 recordings. The audio files were analysed in Prosogram in order to detect possible differences depending on the child’s age. The results showed a noticeable change in child-directed speech over the first year of the child’s life. A change in several characteristic prosodic features was noted to occur between the ages of 6 and 9 months. Pitch levels decreased, and articulation rate increased. Additionally, parents seemed to use pitch values much higher than their mean pitch speaking to children aged 3 and 6 months than to children aged 9 and 12 months. Despite using a relatively small sample, the results show several interesting trends in the usage of child-directed speech. Furthermore, this study shows that Prosogram is a useful tool for automatic analysis of child-directed speech