15th International Congress of Phonetic Sciences (ICPhS-15)
This study investigated acoustic-phonetic characteristics of infant-directed speech to examine the hypothesis that infant-directed speech provides exceptionally clear, exaggerated cues to language. Vowels and lexical tones in Mandarin Chinese were examined. Sixteen mothers were audio-recorded while speaking to their 6-8 month-old infants and to another adult. The results showed that the spectral features of /a/, /i/, and /u/ were altered to stretch the acoustic distances between them and resulted in a greater acoustic area encompassing the articulation space. For lexical tones, the results demonstrated that when talking with infants, Mandarin mothers raised the pitch level, exaggerated pitch contours, and produced a more complete contour at syllable level. Moreover, the critical temporal feature that perceptually distinguishes lexical tones, the relative timing of F0 turning point, was held constant across both speech conditions. Together, the results support the claim that infant-directed speech provides exceptionally well-specified acoustic-phonetic information, which could promote language learning.
Bibliographic reference. Liu, Huei-Mei / Tsao, Feng-Ming / Kuhl, Patricia K. (2003): "Speech input to infants: the acoustic-phonetic characteristics of infant-directed speech in Mandarin Chinese", In ICPhS-15, 901-904.