Feature Story
Tuning in to the bilingual benefits of Cantonese tones
Published on 21 Dec 2020

When Dr William Tsun Man Choi (Croucher Fellowship 2018) was young, he could not hold a Cantonese conversation with his cousins who grew up in English-speaking countries. Now that childhood experience has informed his research on speech perception, that is, listening, and reading – research with the potential to improve how children learn to read and to help those who learn two languages.

Choi’s cousins were not taught Cantonese because their parents believed that would hinder their English language development. “I found this quite unfortunate. We were not able to converse in Cantonese, which is to me a beautiful language,” he said.

“I have used both languages since birth. We used both at home. I have heard of parents stopping speaking Cantonese at home because they believe getting to know Cantonese can hinder English learning. That’s why I want to study this.”

While at University College London as a Croucher Fellow, after completing his PhD at the University of Hong Kong in 2018, Choi devised a study focusing on how Hong Kong children learn to read in both Chinese and English, languages with different scripts. Currently underway on a small scale, this is intended to become a large team project involving universities in Hong Kong and overseas – subject to funding.

“Formal reading instruction typically begins at primary school. Reading difficulties are usually identified at six to seven years, which is pretty late. I wanted to know if there are ways to identify if [children] are at risk even before starting reading comprehension,” he explained.

“One implication is early screening. The skills I look for are what researchers call pre-literacy skills. These are the building blocks of reading development. In previous years, my team and I identified some potential predictors for future reading problems.”

Choi believes early screening may help enable early intervention but realises that this would involve government policy and funding. Thus, follow-up research would need to validate the findings.

How bilingual Cantonese-English listeners hear tones and stress was the basis of Choi’s PhD thesis research. Now, as an Assistant Professor in the Department of Early Childhood Education at the Education University of Hong Kong, he is building on this in his postdoctoral work in psycholinguistics and neurolinguistics. He teaches, but much of his time is spent on researching bilingualism, speech perception and reading development.

Choi headed in this direction after his undergraduate research experience convinced him it best suited him. In 2010, he entered the University of Hong Kong to study speech and hearing sciences. While training to become a speech therapist, he also became passionate about scientific research, being drawn to it as soon as he undertook such work.

Interested in both science and history at secondary school, he chose his study field “kind of by chance”, he said. “When I was in secondary school, I did not really know what I wanted to study. I came across a radio programme and they interviewed two students – one a high achiever in the public exam and one a low achiever. When the high achiever was asked which programme she wanted to enter, she said, ‘speech and hearing sciences at the University of Hong Kong’, and I thought, ‘that’s pretty cool’.” It was also the first time he had heard of the subject.

Clearly, he made the right choice. Choi was frequently on the Dean’s Honours List, entering doctoral studies directly from his bachelor degree. In 2017, the third year of his PhD, he was awarded a prestigious US government Fulbright scholarship to study and conduct research at Massachusetts Institute of Technology, Boston.

His research findings have included a first-authored study, published in Cognition in 2019[3], that demonstrated bilingual adults speaking both Cantonese and English were better able to discriminate English lexical stress – that is, which syllable is emphasised – than native English speakers. This was attributable to their experience of using Cantonese tones, the study concluded.

This was a ground-breaking finding, bucking the usual assumption that non-native listeners are disadvantaged compared with native listeners. “It’s largely believed that your first language would have a negative or at best null effect on perception of foreign speech sounds.” But his work suggested it could help.

Choi was particularly keen to explore tone and stress perception having seen how difficult his friends from other countries found it to distinguish Cantonese tones. “I was interested in this language feature and I wanted to understand how listeners can learn to perceive these tones because for foreigners they are actually very difficult,” he said. “I was intrigued, why tones are so easy for Cantonese speakers but not for those coming from another language background like French or English.”

In an earlier first-authored study, published in the Journal of Experimental Child Psychology in 2016[4], he and his team found that how well a person understands Cantonese tones is related to their ability to understand what they are reading in English as a second language.

Their follow-up work, published in the Journal of Research in Reading in 2017[5], further identified Cantonese tone awareness as a potential key to early identification of Hong Kong children struggling with Chinese and English reading comprehension.

As the article stated, “…the evidence of impoverished lexical tone awareness in both poor Chinese and poor English comprehenders suggests that lexical tone awareness might be used to screen and/or treat reading comprehension difficulties among Chinese-English bilingual children. Such speculations on educational change need careful empirical testing though.”

Choi also devised a solo study on how musical training helps language learning[6], while at University College London’s Institute of Cognitive Neuroscience. The most prominent theory suggested musical training could enhance perception of tones in Mandarin and Cantonese, so he studied English musicians and non-musicians. He found that musical training could facilitate perception of some – but not all – Cantonese tones. “The practical implications are twofold,” he said. “I identified some tones which may be good candidates for musical training.” As well, he found the assumption that musical training can help perception of all tones is not necessarily correct.

For Choi, his research focus means the chance to make a substantial difference across generations. “Scientific research is challenging because you have to come up with novel ideas and you have to really be stringent in every tiny detail of your reasoning. To me, research is macro and far-reaching. The impact of basic research may be less visible and immediate, but it fuels future scientific innovations.”

Dr William Choi is an Assistant Professor in the Department of Early Childhood Education, at the Education University of Hong Kong. He completed his PhD in the Division of Speech and Hearing Sciences, University of Hong Kong. Following his doctorate, he joined the Institute of Cognitive Neuroscience, University College London, with the support of a Croucher Fellowship in 2018.

Extended readings:

  1. Dr Choi’s personal page in Croucher Foundation: https://scholars.croucher.org.hk/scholars/william-tsun-man-choi
  2. Dr Choi’s personal page in The Education University of Hong Kong: https://repository.eduhk.hk/en/persons/tsun-man-william-choi
  3. The scientific article Dr Choi published in Cognition in 2019: https://www.sciencedirect.com/science/article/abs/pii/S0010027719300885
  4. The scientific article Dr Choi published in Journal of Experimental Child Psychology in 2016: https://www.ncbi.nlm.nih.gov/pubmed/27135168
  5. The scientific article Dr Choi published in Journal of Research in Reading in 2017: https://onlinelibrary.wiley.com/doi/full/10.1111/1467-9817.12077
  6. The scientific article Dr Choi published in Music Perception in 2020: https://online.ucpress.edu/mp/article/37/5/423/110587/The-Selectivity-of-Musical-AdvantageMusicians