In a recent study published in the journal Science Advances, French researchers examined how bilingual people neurologically process their respective languages in written form.
The study carried out by a team of clinical neurologists, neuropsychologists and researchers, and funded by the Agence Nationale de la Recherche, found that a part of the brain called the Visual Word Form Area (VWFA) behaves differently for English-Chinese speakers compared to English-French speakers. It has also shed light on specific research towards different forms of bilingualism, with most accredited research comparing monolingualism and bilingualism.
There is much scientific evidence to credit bilingualism beyond its cultural and communication benefits. Being able to speak more than one language is proven to physically change the brain, including increased neuroplasticity and fighting cognitive decline.
In this particular case, researchers focused on writing systems among English-Chinese speakers and English-French speakers, and the participants’ brain activity was monitored using an fMRI machine in response to visual stimuli including letters, faces and houses.
Results showed that with both groups the VWFA responded to stimuli, however when English-Chinese participants read Chinese characters, distinct areas of the VWFA lit up in response.
The team subsequently discovered complex clusters of neurons specifically sensitive to the Chinese language in English-Chinese bilinguals. In English-French bilinguals, brain activity proved to be the same, regardless of language stimuli.
This research also supports working theories that the brain develops in response to an individual’s unique experiences.
Minye Zhan – a leading researcher on the project, explains that the team expected to find some neurological differences between “dominant English speakers, dominant French speakers, and balanced English-French speakers”. They found however that the 21 English-French bilingual participants did not demonstrate any cognitive processing differences, despite their dominance in one language over the other.
Zhan says “It’s the same system,” – “I dug hard and didn’t see any difference. It was a very big surprise.”
In the past, pinpointing brain activity has been a challenge for researchers. With new high resolution technology, such as the 7-Tesla fMRI used in this study, neuropsychologists can allow for more accurate results based on the clarity of images. Here, the researchers saw intensely detailed clusters of neurons when certain participants responded to Chinese. According to Zhan, it was “a galaxy, a constellation of areas.”
“The interesting part is that there are these word patches that process both languages, even different languages like English and Chinese,” Zhan continues. “They’re so different, but they are processed in the same area, although there are specialized Chinese-only language patches in the brain.”
The researchers noted that the cognitive response to Chinese stimuli overlapped with areas of the brain that allow facial recognition, suggesting that Chinese characters – made up of historically symbolic lines and strokes are processed in a visually similar way to faces.
For alphabetic languages such as English and French, part-based processing is more common. Individual letters, or letter combinations, are recognized and processed separately and then merged to form a coherent word.
The results of this study suggest learning Chinese – including the way reading is taught, might place unique demands on neural pathways, resulting in different connections – although the reasons behind the findings remain speculation for now and raise more questions.
Zhan says “So why do those special patches come up?” -“That we don’t know. We just observe them. So we report first and say that it needs more research.”
