Intonation Contour of Japanese Maternal Infant-Directed Speech and Infant Vocal Response

要旨

We investigated the developmental change in infants' early vocal communication through mother-infant interaction. In this study, we concentrated on the age-related changes in intonation contours in maternal infant-directed speech, and those of infant vocal response to maternal speech with different patterns of intonation contour. Speech samples of 50 Japanese mother-infant dyads were recorded from 3 to 9 months after birth. The fundamental frequency of the mother's speech during mother-infant interaction was extracted, and the intonation contours were determined based on acoustic analysis. We found that the appearance of intonation contour patterns in maternal infant-directed speech depends on the infant's age. The infant's response to each pattern of intonation contour in maternal speech also showed age-related changes. These results suggest that the mothers modified their pattern of intonation contour in terms of their infants' development during the first 9 months.

主題