Turn taking affects the quality of infant vocalizations

Two groups of 20 infants aged 0; 3 experienced either conversational turn taking or random responsiveness of an adult. All infant vocalizations were counted and then each was categorized as a speech-like (syllabic) sound or a nonspeech-like (vocalic) sound. The results of this experiment indicated that turn taking caused changes in the quality of infant vocal sounds. When the adult maintained a give-and-take pattern, the infant produced a higher ratio of syllabic/vocalic sounds. The effect of turn taking on infant vocalizations was discussed in terms of its possible adaptive value for adult responsiveness.