An Acoustic Study Of Southern Mandarin Young Children’s Acquisition Of Vowel Space

The present study is a longitudinal study of two Southern Mandarin young malechildren aged0;9-2;0. The purpose of this study is to investigate the relationshipbetween motherese and the development of vowel space in Southern Mandarin children，providing systematic evidence for Southern Mandarin children’s phonetic acquisition,and to examine the Hypothesis of Early Interaction. The significance of the study liesin addressing the research gap in the ambient effect on the development of vowel spacein Southern Mandarin young children. This study covers the period of nine totwenty-four months of life.Specifically, there are three research questions below:Question1: What is the changing trend of F1and F2of the vowels in the SouthernMandarin young children?Question2: What are the acoustic characteristics of the children’s vowel space?Question3: How is the ambient effect reflected in the children’s acquisition ofvowel space?In this longitudinal research, the subjects are two Changsha Mandarin malechildren (XZ and LY) aged0;9-2;0and their mothers. They are the ifrst babies born tothe family and healthy with no cognitive and hearing as well as speaking impairment.Southern Mandarin is their daily language. They were audio-taped (SONY ICD-SX35)and video-taped (SONY HDR-HC1) at their homes almost every week, and eachrecording lasted about50-60minutes. All the data we are obtained under naturalcircumstances by the MA students, the parents were in natural communication with thetwo children respectively. There are24recording sessions for each of the child. XZ’smother was present for16times, while LY’s mother presented herself every time andinteracted with her child all the time.The utterances were taken from the age period0;9，1;0，1;3，1;6，1;9，2;0. The dataof the two children are extracted from the selected24sessions. All together, there are984vowel tokens in the two subjects.404vowel tokens are from XZ and580voweltokens from LY. There are276vowel tokens from the mothers and each shares an equalnumber of the vowels. The data were transcribed in narrow IPA. All the recordings weretransferred into PC for segmentation and analysis. The author converted thea’udio-recordings into the ’.wav form through Cool Edit Pro (version2.1) andtextgrided them by Praat (Version5.1.37). Finally, the absolute vowel formant values were obtained by using a script. The transcription was completed by the researchersmajoring in this ifeld and was checked by two MA students majoring in Linguistics.The intra-reliability was96.75%and the inter-reliability was91.05%.The major ifndings are:1)The young children’s values of the vowel formants tend to decrease with thegrowth of age and they produce target F1and F2with less variability. The ifndings areconsistent with Eguchi&Hirsh’s.2)There is an expansion of the vowel space. And the F1and F2of the vowels getmore and more widely spread in the vowel space chart. Besides，both children showeda developmental expansion of the size of the vowel space along the diffuse-gravedimension and the expansion of grave corner was comparatively more prominent.3)This study supports Boysson-Bardies’s Hypothesis of Early Interaction. To bemore specific, the frequency of interaction between child and his mother affects theprogress of drift towards his ambient language. The ifndings are not in support of theIndependent Hypothesis.