The relationship between prosodic and syntactic organization in early multiword speech

Several descriptions of the transition from single to multiword utterances use prosody as an important diagnostic criterion. For example, in contrast to successive single-word utterances, 'real' two-word utterances are supposed to be characterized by a unifying intonation contour and a lack of an intervening pause. Research on the acquisition of prosody, however, revealed that control of the phonetic parameters pitch, loudness, and duration is far from complete at such an early stage. In this study, we examine the interaction between the development of different types of syntactic structures and their prosodic organization. Data from a detailed production record of a monolingual German-learning boy is analysed both auditorily and acoustically with a focus on four different types of two-word utterances produced between 2;0 and 2;3. Two major findings are reported here. First, the different types of two-word utterances undergo individual trajectories of prosodic (re-)organization, in part depending on the time course in which they become productive. This suggests that different types of multiword utterances become prosodically fluent at different points in time. Second, the variability of prosodic features such as pauses and stress pattern is very high at the onset of combinatorial speech. Consequently, fluency or disfluency of individual examples should not be used as a reliable criterion for their syntactic status and we recommend caution when taking prosody as a cue for syntactic development.