Emergence of the vowel space in very young children with Down syndrome: An exploratory case study

The current study presents the preliminary results of an investigation into the development of the vowel space in one female child with Down syndrome (DS). Vowel productions at five points in time, ranging from 1;0 to 3;8 years of age, have been analysed to produce age-specific F1-F2 vowel plots and to calculate metrics quantifying changes in their size and dimensions. The results show that changes in DS vowel space area and shape are non-systematic, lacking the definite developmental trajectories present in the productions of typically developing children. An explanation of outcomes using the DIVA model of speech acquisition is proposed.