Rewired for Language

In Mandarin Chinese there are four ways to pronounce “ma,” and each has a totally different meaning. Say it with a certain tone and it means “mother.” But beware – say it slightly differently and it means “horse.”

Tonal differences occur frequently in Mandarin but not in languages like English, making the pairing an ideal case study for understanding how the human brain rewires itself to learn new languages. Statistician Abhra Sarkar and auditory neuroscientist Bharath Chandrasekaran and their teams are exploring the topic now.

“This could help eventually in developing precision learning strategies for different people depending on how their individual brains work,” said Sarkar, an assistant professor in UT Austin’s Department of Statistics and Data Sciences.

By exploring the differences in tone learning between bilingual and unilingual children and conducting experiments, the researchers are working to better understand language learning.

In the team’s early experiments, English speakers learned how to differentiate four different tonal variations while listening to a Mandarin speaker. Over time, participants identified the tones more quickly and accurately, and the statisticians then developed a way to model how the brain learns language over time and which factors make a difference in the pace of that learning. It turns out language learners of varying skill levels need the same amount of audio information to tell the four tones apart. But good learners process the same amount of information more quickly.

Beyond helping people learn new languages, the statistical model – which has now been validated on data collected from the experiment – might help clinicians understand why an individual has a speech or hearing disorder. It could also help neuroscientists studying other skills, such as how we make sense of the visual world. The team next plans to look into how visual learning is the same as or different from auditory learning.

In conducting experiments and exploring differences in tone learning, the researchers are working to better understand language learning.