A Comparison Of Mandarin-speaking Children's Pitch At The Pre-linguistic And Early Speech Stages

The thesis studies the prosodic development of 9 Mandarin infants (5 males and 4 females) in Changsha through the acoustic and statistic analyzes of the infants'data from their pre-linguistic and early speech stages. It focuses on the following aspects: 1) what are the prosodic characteristics of the Mandarin infants in these two stages? Are the prosodic characteristics similar or different? Do they reflect universal prosodic characteristics comparing with the prosodic development of other language communities? 2) Are there any significant or systematic gender differences between and within different age groups? 3) Does the distribution of prosodic patterns change from the early through the later stages of infants'vocalizations? Does it consist with the continuity or discontinuity model? 4) Does the infants'prosodic development reflect the language-specific effects in the two stages?The mean age for the infants in the pre-linguistic group is 0;10;23, which is in the first stage (0;6;0 to 1;0;0) according to Locke's (1983) three continuous stages in early phonological development; and the mean age for infants in the early speech group is 1;8;14, which is in the third stage (after 1;6;0) according to Locke's research. The age differences among subjects within each group are less than 1 month. The current research data are composed of 2 sessions from each subject, one session is from the pre-linguistic stage and the other is from the early speech stage. All together there is an analysis of 18 sessions of recordings (each recording is from 45 to 40 minutes) and all the data are recorded under natural setting.The present research chooses the monosyllable, because this type of syllable occurs frequently in the two stages. Cool Edit and Praat are adopted in extracting and analyzing the data and totally 2009 usable monosyllables are obtained. By means of the Praat script, the F0 of syllables is normalized in the way of Lz-score and the Lz-score value of each syllable is then converted to a relative pitch level description on a five-point scale.After the acoustic and statistic analysis, the following results have been obtained: 1) the level and simple prosodic patterns are highly frequent in the infants'prosodic production for the two stages. Furthermore, the infants all prefer the production of high relative pitch. There are similarities as well as differences in the prosodic production between the two age groups. Certain universal characteristics could be observed in comparing the data with those of other language communities; 2) certain gender differences could be observed but not systematic; 3) development continuity can be observed between the two age groups in prosodic development; 4) obvious evidence for language-specific effects can be found in both pre-linguistic and early speech stages. This empirical research provided evidence for the continuity model from the aspect of pitch acquisition.