The “fine-tuning” hypothesis of adult speech to children: Effects of experience and feedback

When adults speak to children, they shorten and simplify their utterances. Bohannon and Marquis (1977) demonstrated that children’s verbal feedback could “fine-tune” the length of adult utterances by indicating comprehension or noncomprehension of the preceding adult utterance. The present studies were designed to (1) assess the relative importance of verbal and nonverbal feedback in this process, (2) test the hypothesis that an adult’s experience with one child’s feedback would generalize to another child, and (3) evaluate the role of previous experience. In Study 1, subjects were shown videotape recordings of a child giving either comprehension or noncomprehension verbal and nonverbal signals, and the tapes were shown with or without sound. All subjects told a story to a picture of a familiar child (seen in the videotape) and to a picture of a novel child. The length of the utterances addressed to the picture of the familiar child was sensitive to the different verbal signals heard earlier, but this did not generalize to the novel child, nor were the nonverbal signals effective in changing the adults’ narratives. In Study 2, subjects answered a questionnaire assessing their experience with children and told a story to each of three pictures, one of an adult and two of children. No significant differences were found in the narratives due to differing experience. However, the speech addressed to the children’s pictures was simpler than that addressed to the picture of the adult.