Pitch characteristics of Japanese maternal speech to infants.

The fundamental frequency F0 patterns of maternal-speech addressed to infants aged 0;3-0;4 were measured quantitatively. Speech samples were recorded when six Japanese-speaking mothers addressed an adult and their own infants. Japanese mothers speaking to adults use a relatively restricted F0 range, concentrated around the mother's F0, which tends to be near the low end of the total range used. These acoustic characteristics are not altered substantially when these same women speak to their infants in initial utterances to attract the infants' attention. If such attempts are unsuccessful, however, they are likely to make more exaggerated utterances, in which F0 shifts upward and the frequency range is significantly increased. Moreover, only when acoustic characteristics of maternal speech to infants are exaggerated, can the type of F0 contour of the infant's subsequent response be predicted to a significant extent from the mother's preceding utterance.