This study examines individual paths to the category formation of the L2 Mandarin /ʂ/-/ɕ/ contrast. An important aspect of second language speech is that learners have a wide range of individual differences Baker Saito, 2019. However, individual differences are often ignored when examining phonological category formation. Furthermore, theoretical models are typically supported by one type of data Flege, 1987; Best & Tyler, 2007. This can obscure information about how learners acquire new contrasts. As such, this study examines ultrasound and acoustic data from 8 L1 English-L2 Mandarin speakers producing /ʂ/-/ɕ/. Subsequently, participants completed an ABX perceptual categorization task. Results show that of the five learners who accurately categorize Mandarin sibilants, two do not produce them with distinct tongue positions or acoustic values. Interestingly, of the three learners who do not accurately categorize the sibilants, one does produce them with distinct tongue positions. These results exemplify learners who perceive a contrast but do not accurately produce it and also show that learners may have more difficulty perceiving a contrast in an experimental setting than producing the contrast. These data show distinct paths speakers take when acquiring a novel contrast and have implications for how speech sounds are represented.
Madeleine Oakley (Wed,) studied this question.