Some Singaporean parents wonder whether exposing their child to multiple languages has any influence on their child’s language learning.
To investigate this relationship between language exposure patterns and language development in Singaporean children, we invited a group of local children aged 5.5 to 6 years old to complete an auditory discrimination task – Flower Crown Task. The children were asked to decide on the identity of the speech sound they heard.
During the Flower Crown Task, the children sat in front of a computer and were asked to put on headphones and place their fingers on specific keys on a keyboard. They then made decisions for a little monkey to either eat a “peach” or go to the “beach”, based on the auditory token they heard. The starting consonants of these two words (/p/ and /b/) differ by their Voice Onset Time (VoT), which is the time it takes for voicing to occur after the burst of air is released from mouth when we make the sound /p/ or /b/. For /p/, voicing starts after the burst of air is released (average VoT = +30 millisecond) and for /b/, voicing starts before the burst of air is released (average VoT = -30 millisecond). Using a computer program, we created 16 tokens with continuous voice onset times from -60ms to +90ms. The tokens on one end of the range sound more like /p/ and on the other end of range sound more like /b/. When the children are asked to decide which sound they heard based on the token, it helps us understand how sensitive children are in discriminating between basic language building blocks such as speech sounds, an ability crucial to children’s language learning.
Next, we also wanted to know whether different language exposure patterns had an influence on how well children tell apart different speech sounds (such as /p/ and /b/). We collected this information on proportions of their language exposure (what they read and/or heard) and output (what they spoke and/or wrote). The children had varying exposure rates of English and Mandarin. We predicted that differing proportions of exposure to English and Mandarin may lead to different performances on the Flower Crown Task, in particular, exposure to more English may lead to the child being better at discriminating English speech sounds.
Data from 77 children were included and presented at two conference presentations last year. At the Architectures and Mechanisms for Language Processing conference in September 2020, we shared how our prediction turned out to be inaccurate. Whether a Singaporean child has more exposure to English or Mandarin does not reflect how well they performed in discriminating English speech sounds. This suggests that having more exposure to Mandarin (or any other language that is not English) isn’t likely to pose a problem for Singaporean children to learn English.
Additionally, we compared the pattern of reaction time in our Flower Crown Task of Singaporean children vs. Singaporean adults. Typically, adults react faster when they heard tokens from two ends of the VoT range as the tokens would sound more like a /p/ or a /b/ sound. They react much slower when they hear tokens at the crossover point because it becomes ambiguous whether the sound was more like a /p/ or a /b/. So when we plot the reaction time, we will see an inverted U shape. While reaction time of the Singapore adults group showed a typical inverted U shape pattern, this pattern was not clear in the child group. This suggests that for Singaporean children between 5.5 and 6 years old, the phoneme discrimination ability has not matured yet. This set of results was presented at the Boston University Conference on Language Development in November 2020.
We want to thank all the families who contributed to this project! If you would like to know more about this study, please visit this link for a conference presentation video walk-through: https://osf.io/xwsdy/
This was written by our Research Fellow, Dr Ke Han. She is a Post-doctoral Research Fellow in the BLIP Lab working on EEG of babies’ language development.