Speaker attribution of successive utterances: The role of discontinuities in voice characteristics and prosody
In our work we attempted to answer the following question: How do listeners identify two sentences as spoken by one or by two persons when they can take into consideration only acoustic speaker characteristics and intonation? We used successive utterance portions forming a single turn or two subsequent turns in a dialogue, the lexical structure of which was held constant. The experiments are based on sentence combinations varying with respect to speakers, sentence types, and types of communicative coherence, Pairs of sentences with and without constant intervening pauses were presented to subjects with the task of ascribing them to one of three categories: ''dialogue'', ''monologue'' and ''metadialogue'' (i.e., the imitation of dialogue by a single voice). The results showed that the following factors influence the decision of the listeners: voice properties, presence or absence of pause, and the communicative types of the sentences. Two principles involved in processing the input signals are supposed. One of them is applied to the case when two sentences are represented without a pause. Under these circumstances, the continuity or discontinuity of the acoustic input is likely to be the main criterion used by the listener to decide between ''monologue'' and ''dialogue''. If the sentences are separated by a pause, a comparison of the auditory voice properties of the two portions may take place.
speaker attribution voice characteristics intonation auditory processing perceptual organization